1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Linux Socket Filter - Kernel level socket filtering
4  *
5  * Based on the design of the Berkeley Packet Filter. The new
6  * internal format has been designed by PLUMgrid:
7  *
8  *	Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
9  *
10  * Authors:
11  *
12  *	Jay Schulist <jschlst@samba.org>
13  *	Alexei Starovoitov <ast@plumgrid.com>
14  *	Daniel Borkmann <dborkman@redhat.com>
15  *
16  * Andi Kleen - Fix a few bad bugs and races.
17  * Kris Katterjohn - Added many additional checks in bpf_check_classic()
18  */
19 
20 #include <linux/atomic.h>
21 #include <linux/bpf_verifier.h>
22 #include <linux/module.h>
23 #include <linux/types.h>
24 #include <linux/mm.h>
25 #include <linux/fcntl.h>
26 #include <linux/socket.h>
27 #include <linux/sock_diag.h>
28 #include <linux/in.h>
29 #include <linux/inet.h>
30 #include <linux/netdevice.h>
31 #include <linux/if_packet.h>
32 #include <linux/if_arp.h>
33 #include <linux/gfp.h>
34 #include <net/inet_common.h>
35 #include <net/ip.h>
36 #include <net/protocol.h>
37 #include <net/netlink.h>
38 #include <linux/skbuff.h>
39 #include <linux/skmsg.h>
40 #include <net/sock.h>
41 #include <net/flow_dissector.h>
42 #include <linux/errno.h>
43 #include <linux/timer.h>
44 #include <linux/uaccess.h>
45 #include <asm/unaligned.h>
46 #include <linux/filter.h>
47 #include <linux/ratelimit.h>
48 #include <linux/seccomp.h>
49 #include <linux/if_vlan.h>
50 #include <linux/bpf.h>
51 #include <linux/btf.h>
52 #include <net/sch_generic.h>
53 #include <net/cls_cgroup.h>
54 #include <net/dst_metadata.h>
55 #include <net/dst.h>
56 #include <net/sock_reuseport.h>
57 #include <net/busy_poll.h>
58 #include <net/tcp.h>
59 #include <net/xfrm.h>
60 #include <net/udp.h>
61 #include <linux/bpf_trace.h>
62 #include <net/xdp_sock.h>
63 #include <linux/inetdevice.h>
64 #include <net/inet_hashtables.h>
65 #include <net/inet6_hashtables.h>
66 #include <net/ip_fib.h>
67 #include <net/nexthop.h>
68 #include <net/flow.h>
69 #include <net/arp.h>
70 #include <net/ipv6.h>
71 #include <net/net_namespace.h>
72 #include <linux/seg6_local.h>
73 #include <net/seg6.h>
74 #include <net/seg6_local.h>
75 #include <net/lwtunnel.h>
76 #include <net/ipv6_stubs.h>
77 #include <net/bpf_sk_storage.h>
78 #include <net/transp_v6.h>
79 #include <linux/btf_ids.h>
80 #include <net/tls.h>
81 #include <net/xdp.h>
82 #include <net/mptcp.h>
83 #include <net/netfilter/nf_conntrack_bpf.h>
84 
85 static const struct bpf_func_proto *
86 bpf_sk_base_func_proto(enum bpf_func_id func_id);
87 
copy_bpf_fprog_from_user(struct sock_fprog * dst,sockptr_t src,int len)88 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len)
89 {
90 	if (in_compat_syscall()) {
91 		struct compat_sock_fprog f32;
92 
93 		if (len != sizeof(f32))
94 			return -EINVAL;
95 		if (copy_from_sockptr(&f32, src, sizeof(f32)))
96 			return -EFAULT;
97 		memset(dst, 0, sizeof(*dst));
98 		dst->len = f32.len;
99 		dst->filter = compat_ptr(f32.filter);
100 	} else {
101 		if (len != sizeof(*dst))
102 			return -EINVAL;
103 		if (copy_from_sockptr(dst, src, sizeof(*dst)))
104 			return -EFAULT;
105 	}
106 
107 	return 0;
108 }
109 EXPORT_SYMBOL_GPL(copy_bpf_fprog_from_user);
110 
111 /**
112  *	sk_filter_trim_cap - run a packet through a socket filter
113  *	@sk: sock associated with &sk_buff
114  *	@skb: buffer to filter
115  *	@cap: limit on how short the eBPF program may trim the packet
116  *
117  * Run the eBPF program and then cut skb->data to correct size returned by
118  * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
119  * than pkt_len we keep whole skb->data. This is the socket level
120  * wrapper to bpf_prog_run. It returns 0 if the packet should
121  * be accepted or -EPERM if the packet should be tossed.
122  *
123  */
sk_filter_trim_cap(struct sock * sk,struct sk_buff * skb,unsigned int cap)124 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
125 {
126 	int err;
127 	struct sk_filter *filter;
128 
129 	/*
130 	 * If the skb was allocated from pfmemalloc reserves, only
131 	 * allow SOCK_MEMALLOC sockets to use it as this socket is
132 	 * helping free memory
133 	 */
134 	if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
135 		NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
136 		return -ENOMEM;
137 	}
138 	err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
139 	if (err)
140 		return err;
141 
142 	err = security_sock_rcv_skb(sk, skb);
143 	if (err)
144 		return err;
145 
146 	rcu_read_lock();
147 	filter = rcu_dereference(sk->sk_filter);
148 	if (filter) {
149 		struct sock *save_sk = skb->sk;
150 		unsigned int pkt_len;
151 
152 		skb->sk = sk;
153 		pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
154 		skb->sk = save_sk;
155 		err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
156 	}
157 	rcu_read_unlock();
158 
159 	return err;
160 }
161 EXPORT_SYMBOL(sk_filter_trim_cap);
162 
BPF_CALL_1(bpf_skb_get_pay_offset,struct sk_buff *,skb)163 BPF_CALL_1(bpf_skb_get_pay_offset, struct sk_buff *, skb)
164 {
165 	return skb_get_poff(skb);
166 }
167 
BPF_CALL_3(bpf_skb_get_nlattr,struct sk_buff *,skb,u32,a,u32,x)168 BPF_CALL_3(bpf_skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
169 {
170 	struct nlattr *nla;
171 
172 	if (skb_is_nonlinear(skb))
173 		return 0;
174 
175 	if (skb->len < sizeof(struct nlattr))
176 		return 0;
177 
178 	if (a > skb->len - sizeof(struct nlattr))
179 		return 0;
180 
181 	nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
182 	if (nla)
183 		return (void *) nla - (void *) skb->data;
184 
185 	return 0;
186 }
187 
BPF_CALL_3(bpf_skb_get_nlattr_nest,struct sk_buff *,skb,u32,a,u32,x)188 BPF_CALL_3(bpf_skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
189 {
190 	struct nlattr *nla;
191 
192 	if (skb_is_nonlinear(skb))
193 		return 0;
194 
195 	if (skb->len < sizeof(struct nlattr))
196 		return 0;
197 
198 	if (a > skb->len - sizeof(struct nlattr))
199 		return 0;
200 
201 	nla = (struct nlattr *) &skb->data[a];
202 	if (nla->nla_len > skb->len - a)
203 		return 0;
204 
205 	nla = nla_find_nested(nla, x);
206 	if (nla)
207 		return (void *) nla - (void *) skb->data;
208 
209 	return 0;
210 }
211 
BPF_CALL_4(bpf_skb_load_helper_8,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)212 BPF_CALL_4(bpf_skb_load_helper_8, const struct sk_buff *, skb, const void *,
213 	   data, int, headlen, int, offset)
214 {
215 	u8 tmp, *ptr;
216 	const int len = sizeof(tmp);
217 
218 	if (offset >= 0) {
219 		if (headlen - offset >= len)
220 			return *(u8 *)(data + offset);
221 		if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
222 			return tmp;
223 	} else {
224 		ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
225 		if (likely(ptr))
226 			return *(u8 *)ptr;
227 	}
228 
229 	return -EFAULT;
230 }
231 
BPF_CALL_2(bpf_skb_load_helper_8_no_cache,const struct sk_buff *,skb,int,offset)232 BPF_CALL_2(bpf_skb_load_helper_8_no_cache, const struct sk_buff *, skb,
233 	   int, offset)
234 {
235 	return ____bpf_skb_load_helper_8(skb, skb->data, skb->len - skb->data_len,
236 					 offset);
237 }
238 
BPF_CALL_4(bpf_skb_load_helper_16,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)239 BPF_CALL_4(bpf_skb_load_helper_16, const struct sk_buff *, skb, const void *,
240 	   data, int, headlen, int, offset)
241 {
242 	__be16 tmp, *ptr;
243 	const int len = sizeof(tmp);
244 
245 	if (offset >= 0) {
246 		if (headlen - offset >= len)
247 			return get_unaligned_be16(data + offset);
248 		if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
249 			return be16_to_cpu(tmp);
250 	} else {
251 		ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
252 		if (likely(ptr))
253 			return get_unaligned_be16(ptr);
254 	}
255 
256 	return -EFAULT;
257 }
258 
BPF_CALL_2(bpf_skb_load_helper_16_no_cache,const struct sk_buff *,skb,int,offset)259 BPF_CALL_2(bpf_skb_load_helper_16_no_cache, const struct sk_buff *, skb,
260 	   int, offset)
261 {
262 	return ____bpf_skb_load_helper_16(skb, skb->data, skb->len - skb->data_len,
263 					  offset);
264 }
265 
BPF_CALL_4(bpf_skb_load_helper_32,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)266 BPF_CALL_4(bpf_skb_load_helper_32, const struct sk_buff *, skb, const void *,
267 	   data, int, headlen, int, offset)
268 {
269 	__be32 tmp, *ptr;
270 	const int len = sizeof(tmp);
271 
272 	if (likely(offset >= 0)) {
273 		if (headlen - offset >= len)
274 			return get_unaligned_be32(data + offset);
275 		if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
276 			return be32_to_cpu(tmp);
277 	} else {
278 		ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
279 		if (likely(ptr))
280 			return get_unaligned_be32(ptr);
281 	}
282 
283 	return -EFAULT;
284 }
285 
BPF_CALL_2(bpf_skb_load_helper_32_no_cache,const struct sk_buff *,skb,int,offset)286 BPF_CALL_2(bpf_skb_load_helper_32_no_cache, const struct sk_buff *, skb,
287 	   int, offset)
288 {
289 	return ____bpf_skb_load_helper_32(skb, skb->data, skb->len - skb->data_len,
290 					  offset);
291 }
292 
convert_skb_access(int skb_field,int dst_reg,int src_reg,struct bpf_insn * insn_buf)293 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
294 			      struct bpf_insn *insn_buf)
295 {
296 	struct bpf_insn *insn = insn_buf;
297 
298 	switch (skb_field) {
299 	case SKF_AD_MARK:
300 		BUILD_BUG_ON(sizeof_field(struct sk_buff, mark) != 4);
301 
302 		*insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
303 				      offsetof(struct sk_buff, mark));
304 		break;
305 
306 	case SKF_AD_PKTTYPE:
307 		*insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET);
308 		*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
309 #ifdef __BIG_ENDIAN_BITFIELD
310 		*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
311 #endif
312 		break;
313 
314 	case SKF_AD_QUEUE:
315 		BUILD_BUG_ON(sizeof_field(struct sk_buff, queue_mapping) != 2);
316 
317 		*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
318 				      offsetof(struct sk_buff, queue_mapping));
319 		break;
320 
321 	case SKF_AD_VLAN_TAG:
322 		BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_tci) != 2);
323 
324 		/* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
325 		*insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
326 				      offsetof(struct sk_buff, vlan_tci));
327 		break;
328 	case SKF_AD_VLAN_TAG_PRESENT:
329 		*insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_VLAN_PRESENT_OFFSET);
330 		if (PKT_VLAN_PRESENT_BIT)
331 			*insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, PKT_VLAN_PRESENT_BIT);
332 		if (PKT_VLAN_PRESENT_BIT < 7)
333 			*insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
334 		break;
335 	}
336 
337 	return insn - insn_buf;
338 }
339 
convert_bpf_extensions(struct sock_filter * fp,struct bpf_insn ** insnp)340 static bool convert_bpf_extensions(struct sock_filter *fp,
341 				   struct bpf_insn **insnp)
342 {
343 	struct bpf_insn *insn = *insnp;
344 	u32 cnt;
345 
346 	switch (fp->k) {
347 	case SKF_AD_OFF + SKF_AD_PROTOCOL:
348 		BUILD_BUG_ON(sizeof_field(struct sk_buff, protocol) != 2);
349 
350 		/* A = *(u16 *) (CTX + offsetof(protocol)) */
351 		*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
352 				      offsetof(struct sk_buff, protocol));
353 		/* A = ntohs(A) [emitting a nop or swap16] */
354 		*insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
355 		break;
356 
357 	case SKF_AD_OFF + SKF_AD_PKTTYPE:
358 		cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
359 		insn += cnt - 1;
360 		break;
361 
362 	case SKF_AD_OFF + SKF_AD_IFINDEX:
363 	case SKF_AD_OFF + SKF_AD_HATYPE:
364 		BUILD_BUG_ON(sizeof_field(struct net_device, ifindex) != 4);
365 		BUILD_BUG_ON(sizeof_field(struct net_device, type) != 2);
366 
367 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
368 				      BPF_REG_TMP, BPF_REG_CTX,
369 				      offsetof(struct sk_buff, dev));
370 		/* if (tmp != 0) goto pc + 1 */
371 		*insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
372 		*insn++ = BPF_EXIT_INSN();
373 		if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
374 			*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
375 					    offsetof(struct net_device, ifindex));
376 		else
377 			*insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
378 					    offsetof(struct net_device, type));
379 		break;
380 
381 	case SKF_AD_OFF + SKF_AD_MARK:
382 		cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
383 		insn += cnt - 1;
384 		break;
385 
386 	case SKF_AD_OFF + SKF_AD_RXHASH:
387 		BUILD_BUG_ON(sizeof_field(struct sk_buff, hash) != 4);
388 
389 		*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
390 				    offsetof(struct sk_buff, hash));
391 		break;
392 
393 	case SKF_AD_OFF + SKF_AD_QUEUE:
394 		cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
395 		insn += cnt - 1;
396 		break;
397 
398 	case SKF_AD_OFF + SKF_AD_VLAN_TAG:
399 		cnt = convert_skb_access(SKF_AD_VLAN_TAG,
400 					 BPF_REG_A, BPF_REG_CTX, insn);
401 		insn += cnt - 1;
402 		break;
403 
404 	case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
405 		cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
406 					 BPF_REG_A, BPF_REG_CTX, insn);
407 		insn += cnt - 1;
408 		break;
409 
410 	case SKF_AD_OFF + SKF_AD_VLAN_TPID:
411 		BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_proto) != 2);
412 
413 		/* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
414 		*insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
415 				      offsetof(struct sk_buff, vlan_proto));
416 		/* A = ntohs(A) [emitting a nop or swap16] */
417 		*insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
418 		break;
419 
420 	case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
421 	case SKF_AD_OFF + SKF_AD_NLATTR:
422 	case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
423 	case SKF_AD_OFF + SKF_AD_CPU:
424 	case SKF_AD_OFF + SKF_AD_RANDOM:
425 		/* arg1 = CTX */
426 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
427 		/* arg2 = A */
428 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
429 		/* arg3 = X */
430 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
431 		/* Emit call(arg1=CTX, arg2=A, arg3=X) */
432 		switch (fp->k) {
433 		case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
434 			*insn = BPF_EMIT_CALL(bpf_skb_get_pay_offset);
435 			break;
436 		case SKF_AD_OFF + SKF_AD_NLATTR:
437 			*insn = BPF_EMIT_CALL(bpf_skb_get_nlattr);
438 			break;
439 		case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
440 			*insn = BPF_EMIT_CALL(bpf_skb_get_nlattr_nest);
441 			break;
442 		case SKF_AD_OFF + SKF_AD_CPU:
443 			*insn = BPF_EMIT_CALL(bpf_get_raw_cpu_id);
444 			break;
445 		case SKF_AD_OFF + SKF_AD_RANDOM:
446 			*insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
447 			bpf_user_rnd_init_once();
448 			break;
449 		}
450 		break;
451 
452 	case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
453 		/* A ^= X */
454 		*insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
455 		break;
456 
457 	default:
458 		/* This is just a dummy call to avoid letting the compiler
459 		 * evict __bpf_call_base() as an optimization. Placed here
460 		 * where no-one bothers.
461 		 */
462 		BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
463 		return false;
464 	}
465 
466 	*insnp = insn;
467 	return true;
468 }
469 
convert_bpf_ld_abs(struct sock_filter * fp,struct bpf_insn ** insnp)470 static bool convert_bpf_ld_abs(struct sock_filter *fp, struct bpf_insn **insnp)
471 {
472 	const bool unaligned_ok = IS_BUILTIN(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS);
473 	int size = bpf_size_to_bytes(BPF_SIZE(fp->code));
474 	bool endian = BPF_SIZE(fp->code) == BPF_H ||
475 		      BPF_SIZE(fp->code) == BPF_W;
476 	bool indirect = BPF_MODE(fp->code) == BPF_IND;
477 	const int ip_align = NET_IP_ALIGN;
478 	struct bpf_insn *insn = *insnp;
479 	int offset = fp->k;
480 
481 	if (!indirect &&
482 	    ((unaligned_ok && offset >= 0) ||
483 	     (!unaligned_ok && offset >= 0 &&
484 	      offset + ip_align >= 0 &&
485 	      offset + ip_align % size == 0))) {
486 		bool ldx_off_ok = offset <= S16_MAX;
487 
488 		*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H);
489 		if (offset)
490 			*insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset);
491 		*insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP,
492 				      size, 2 + endian + (!ldx_off_ok * 2));
493 		if (ldx_off_ok) {
494 			*insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
495 					      BPF_REG_D, offset);
496 		} else {
497 			*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_D);
498 			*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_TMP, offset);
499 			*insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
500 					      BPF_REG_TMP, 0);
501 		}
502 		if (endian)
503 			*insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8);
504 		*insn++ = BPF_JMP_A(8);
505 	}
506 
507 	*insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
508 	*insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D);
509 	*insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H);
510 	if (!indirect) {
511 		*insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset);
512 	} else {
513 		*insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X);
514 		if (fp->k)
515 			*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset);
516 	}
517 
518 	switch (BPF_SIZE(fp->code)) {
519 	case BPF_B:
520 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8);
521 		break;
522 	case BPF_H:
523 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16);
524 		break;
525 	case BPF_W:
526 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32);
527 		break;
528 	default:
529 		return false;
530 	}
531 
532 	*insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2);
533 	*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
534 	*insn   = BPF_EXIT_INSN();
535 
536 	*insnp = insn;
537 	return true;
538 }
539 
540 /**
541  *	bpf_convert_filter - convert filter program
542  *	@prog: the user passed filter program
543  *	@len: the length of the user passed filter program
544  *	@new_prog: allocated 'struct bpf_prog' or NULL
545  *	@new_len: pointer to store length of converted program
546  *	@seen_ld_abs: bool whether we've seen ld_abs/ind
547  *
548  * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
549  * style extended BPF (eBPF).
550  * Conversion workflow:
551  *
552  * 1) First pass for calculating the new program length:
553  *   bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs)
554  *
555  * 2) 2nd pass to remap in two passes: 1st pass finds new
556  *    jump offsets, 2nd pass remapping:
557  *   bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs)
558  */
bpf_convert_filter(struct sock_filter * prog,int len,struct bpf_prog * new_prog,int * new_len,bool * seen_ld_abs)559 static int bpf_convert_filter(struct sock_filter *prog, int len,
560 			      struct bpf_prog *new_prog, int *new_len,
561 			      bool *seen_ld_abs)
562 {
563 	int new_flen = 0, pass = 0, target, i, stack_off;
564 	struct bpf_insn *new_insn, *first_insn = NULL;
565 	struct sock_filter *fp;
566 	int *addrs = NULL;
567 	u8 bpf_src;
568 
569 	BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
570 	BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
571 
572 	if (len <= 0 || len > BPF_MAXINSNS)
573 		return -EINVAL;
574 
575 	if (new_prog) {
576 		first_insn = new_prog->insnsi;
577 		addrs = kcalloc(len, sizeof(*addrs),
578 				GFP_KERNEL | __GFP_NOWARN);
579 		if (!addrs)
580 			return -ENOMEM;
581 	}
582 
583 do_pass:
584 	new_insn = first_insn;
585 	fp = prog;
586 
587 	/* Classic BPF related prologue emission. */
588 	if (new_prog) {
589 		/* Classic BPF expects A and X to be reset first. These need
590 		 * to be guaranteed to be the first two instructions.
591 		 */
592 		*new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
593 		*new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
594 
595 		/* All programs must keep CTX in callee saved BPF_REG_CTX.
596 		 * In eBPF case it's done by the compiler, here we need to
597 		 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
598 		 */
599 		*new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
600 		if (*seen_ld_abs) {
601 			/* For packet access in classic BPF, cache skb->data
602 			 * in callee-saved BPF R8 and skb->len - skb->data_len
603 			 * (headlen) in BPF R9. Since classic BPF is read-only
604 			 * on CTX, we only need to cache it once.
605 			 */
606 			*new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
607 						  BPF_REG_D, BPF_REG_CTX,
608 						  offsetof(struct sk_buff, data));
609 			*new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX,
610 						  offsetof(struct sk_buff, len));
611 			*new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX,
612 						  offsetof(struct sk_buff, data_len));
613 			*new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP);
614 		}
615 	} else {
616 		new_insn += 3;
617 	}
618 
619 	for (i = 0; i < len; fp++, i++) {
620 		struct bpf_insn tmp_insns[32] = { };
621 		struct bpf_insn *insn = tmp_insns;
622 
623 		if (addrs)
624 			addrs[i] = new_insn - first_insn;
625 
626 		switch (fp->code) {
627 		/* All arithmetic insns and skb loads map as-is. */
628 		case BPF_ALU | BPF_ADD | BPF_X:
629 		case BPF_ALU | BPF_ADD | BPF_K:
630 		case BPF_ALU | BPF_SUB | BPF_X:
631 		case BPF_ALU | BPF_SUB | BPF_K:
632 		case BPF_ALU | BPF_AND | BPF_X:
633 		case BPF_ALU | BPF_AND | BPF_K:
634 		case BPF_ALU | BPF_OR | BPF_X:
635 		case BPF_ALU | BPF_OR | BPF_K:
636 		case BPF_ALU | BPF_LSH | BPF_X:
637 		case BPF_ALU | BPF_LSH | BPF_K:
638 		case BPF_ALU | BPF_RSH | BPF_X:
639 		case BPF_ALU | BPF_RSH | BPF_K:
640 		case BPF_ALU | BPF_XOR | BPF_X:
641 		case BPF_ALU | BPF_XOR | BPF_K:
642 		case BPF_ALU | BPF_MUL | BPF_X:
643 		case BPF_ALU | BPF_MUL | BPF_K:
644 		case BPF_ALU | BPF_DIV | BPF_X:
645 		case BPF_ALU | BPF_DIV | BPF_K:
646 		case BPF_ALU | BPF_MOD | BPF_X:
647 		case BPF_ALU | BPF_MOD | BPF_K:
648 		case BPF_ALU | BPF_NEG:
649 		case BPF_LD | BPF_ABS | BPF_W:
650 		case BPF_LD | BPF_ABS | BPF_H:
651 		case BPF_LD | BPF_ABS | BPF_B:
652 		case BPF_LD | BPF_IND | BPF_W:
653 		case BPF_LD | BPF_IND | BPF_H:
654 		case BPF_LD | BPF_IND | BPF_B:
655 			/* Check for overloaded BPF extension and
656 			 * directly convert it if found, otherwise
657 			 * just move on with mapping.
658 			 */
659 			if (BPF_CLASS(fp->code) == BPF_LD &&
660 			    BPF_MODE(fp->code) == BPF_ABS &&
661 			    convert_bpf_extensions(fp, &insn))
662 				break;
663 			if (BPF_CLASS(fp->code) == BPF_LD &&
664 			    convert_bpf_ld_abs(fp, &insn)) {
665 				*seen_ld_abs = true;
666 				break;
667 			}
668 
669 			if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) ||
670 			    fp->code == (BPF_ALU | BPF_MOD | BPF_X)) {
671 				*insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X);
672 				/* Error with exception code on div/mod by 0.
673 				 * For cBPF programs, this was always return 0.
674 				 */
675 				*insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2);
676 				*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
677 				*insn++ = BPF_EXIT_INSN();
678 			}
679 
680 			*insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
681 			break;
682 
683 		/* Jump transformation cannot use BPF block macros
684 		 * everywhere as offset calculation and target updates
685 		 * require a bit more work than the rest, i.e. jump
686 		 * opcodes map as-is, but offsets need adjustment.
687 		 */
688 
689 #define BPF_EMIT_JMP							\
690 	do {								\
691 		const s32 off_min = S16_MIN, off_max = S16_MAX;		\
692 		s32 off;						\
693 									\
694 		if (target >= len || target < 0)			\
695 			goto err;					\
696 		off = addrs ? addrs[target] - addrs[i] - 1 : 0;		\
697 		/* Adjust pc relative offset for 2nd or 3rd insn. */	\
698 		off -= insn - tmp_insns;				\
699 		/* Reject anything not fitting into insn->off. */	\
700 		if (off < off_min || off > off_max)			\
701 			goto err;					\
702 		insn->off = off;					\
703 	} while (0)
704 
705 		case BPF_JMP | BPF_JA:
706 			target = i + fp->k + 1;
707 			insn->code = fp->code;
708 			BPF_EMIT_JMP;
709 			break;
710 
711 		case BPF_JMP | BPF_JEQ | BPF_K:
712 		case BPF_JMP | BPF_JEQ | BPF_X:
713 		case BPF_JMP | BPF_JSET | BPF_K:
714 		case BPF_JMP | BPF_JSET | BPF_X:
715 		case BPF_JMP | BPF_JGT | BPF_K:
716 		case BPF_JMP | BPF_JGT | BPF_X:
717 		case BPF_JMP | BPF_JGE | BPF_K:
718 		case BPF_JMP | BPF_JGE | BPF_X:
719 			if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
720 				/* BPF immediates are signed, zero extend
721 				 * immediate into tmp register and use it
722 				 * in compare insn.
723 				 */
724 				*insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
725 
726 				insn->dst_reg = BPF_REG_A;
727 				insn->src_reg = BPF_REG_TMP;
728 				bpf_src = BPF_X;
729 			} else {
730 				insn->dst_reg = BPF_REG_A;
731 				insn->imm = fp->k;
732 				bpf_src = BPF_SRC(fp->code);
733 				insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
734 			}
735 
736 			/* Common case where 'jump_false' is next insn. */
737 			if (fp->jf == 0) {
738 				insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
739 				target = i + fp->jt + 1;
740 				BPF_EMIT_JMP;
741 				break;
742 			}
743 
744 			/* Convert some jumps when 'jump_true' is next insn. */
745 			if (fp->jt == 0) {
746 				switch (BPF_OP(fp->code)) {
747 				case BPF_JEQ:
748 					insn->code = BPF_JMP | BPF_JNE | bpf_src;
749 					break;
750 				case BPF_JGT:
751 					insn->code = BPF_JMP | BPF_JLE | bpf_src;
752 					break;
753 				case BPF_JGE:
754 					insn->code = BPF_JMP | BPF_JLT | bpf_src;
755 					break;
756 				default:
757 					goto jmp_rest;
758 				}
759 
760 				target = i + fp->jf + 1;
761 				BPF_EMIT_JMP;
762 				break;
763 			}
764 jmp_rest:
765 			/* Other jumps are mapped into two insns: Jxx and JA. */
766 			target = i + fp->jt + 1;
767 			insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
768 			BPF_EMIT_JMP;
769 			insn++;
770 
771 			insn->code = BPF_JMP | BPF_JA;
772 			target = i + fp->jf + 1;
773 			BPF_EMIT_JMP;
774 			break;
775 
776 		/* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
777 		case BPF_LDX | BPF_MSH | BPF_B: {
778 			struct sock_filter tmp = {
779 				.code	= BPF_LD | BPF_ABS | BPF_B,
780 				.k	= fp->k,
781 			};
782 
783 			*seen_ld_abs = true;
784 
785 			/* X = A */
786 			*insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
787 			/* A = BPF_R0 = *(u8 *) (skb->data + K) */
788 			convert_bpf_ld_abs(&tmp, &insn);
789 			insn++;
790 			/* A &= 0xf */
791 			*insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
792 			/* A <<= 2 */
793 			*insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
794 			/* tmp = X */
795 			*insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X);
796 			/* X = A */
797 			*insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
798 			/* A = tmp */
799 			*insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
800 			break;
801 		}
802 		/* RET_K is remaped into 2 insns. RET_A case doesn't need an
803 		 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
804 		 */
805 		case BPF_RET | BPF_A:
806 		case BPF_RET | BPF_K:
807 			if (BPF_RVAL(fp->code) == BPF_K)
808 				*insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
809 							0, fp->k);
810 			*insn = BPF_EXIT_INSN();
811 			break;
812 
813 		/* Store to stack. */
814 		case BPF_ST:
815 		case BPF_STX:
816 			stack_off = fp->k * 4  + 4;
817 			*insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
818 					    BPF_ST ? BPF_REG_A : BPF_REG_X,
819 					    -stack_off);
820 			/* check_load_and_stores() verifies that classic BPF can
821 			 * load from stack only after write, so tracking
822 			 * stack_depth for ST|STX insns is enough
823 			 */
824 			if (new_prog && new_prog->aux->stack_depth < stack_off)
825 				new_prog->aux->stack_depth = stack_off;
826 			break;
827 
828 		/* Load from stack. */
829 		case BPF_LD | BPF_MEM:
830 		case BPF_LDX | BPF_MEM:
831 			stack_off = fp->k * 4  + 4;
832 			*insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD  ?
833 					    BPF_REG_A : BPF_REG_X, BPF_REG_FP,
834 					    -stack_off);
835 			break;
836 
837 		/* A = K or X = K */
838 		case BPF_LD | BPF_IMM:
839 		case BPF_LDX | BPF_IMM:
840 			*insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
841 					      BPF_REG_A : BPF_REG_X, fp->k);
842 			break;
843 
844 		/* X = A */
845 		case BPF_MISC | BPF_TAX:
846 			*insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
847 			break;
848 
849 		/* A = X */
850 		case BPF_MISC | BPF_TXA:
851 			*insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
852 			break;
853 
854 		/* A = skb->len or X = skb->len */
855 		case BPF_LD | BPF_W | BPF_LEN:
856 		case BPF_LDX | BPF_W | BPF_LEN:
857 			*insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
858 					    BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
859 					    offsetof(struct sk_buff, len));
860 			break;
861 
862 		/* Access seccomp_data fields. */
863 		case BPF_LDX | BPF_ABS | BPF_W:
864 			/* A = *(u32 *) (ctx + K) */
865 			*insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
866 			break;
867 
868 		/* Unknown instruction. */
869 		default:
870 			goto err;
871 		}
872 
873 		insn++;
874 		if (new_prog)
875 			memcpy(new_insn, tmp_insns,
876 			       sizeof(*insn) * (insn - tmp_insns));
877 		new_insn += insn - tmp_insns;
878 	}
879 
880 	if (!new_prog) {
881 		/* Only calculating new length. */
882 		*new_len = new_insn - first_insn;
883 		if (*seen_ld_abs)
884 			*new_len += 4; /* Prologue bits. */
885 		return 0;
886 	}
887 
888 	pass++;
889 	if (new_flen != new_insn - first_insn) {
890 		new_flen = new_insn - first_insn;
891 		if (pass > 2)
892 			goto err;
893 		goto do_pass;
894 	}
895 
896 	kfree(addrs);
897 	BUG_ON(*new_len != new_flen);
898 	return 0;
899 err:
900 	kfree(addrs);
901 	return -EINVAL;
902 }
903 
904 /* Security:
905  *
906  * As we dont want to clear mem[] array for each packet going through
907  * __bpf_prog_run(), we check that filter loaded by user never try to read
908  * a cell if not previously written, and we check all branches to be sure
909  * a malicious user doesn't try to abuse us.
910  */
check_load_and_stores(const struct sock_filter * filter,int flen)911 static int check_load_and_stores(const struct sock_filter *filter, int flen)
912 {
913 	u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
914 	int pc, ret = 0;
915 
916 	BUILD_BUG_ON(BPF_MEMWORDS > 16);
917 
918 	masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
919 	if (!masks)
920 		return -ENOMEM;
921 
922 	memset(masks, 0xff, flen * sizeof(*masks));
923 
924 	for (pc = 0; pc < flen; pc++) {
925 		memvalid &= masks[pc];
926 
927 		switch (filter[pc].code) {
928 		case BPF_ST:
929 		case BPF_STX:
930 			memvalid |= (1 << filter[pc].k);
931 			break;
932 		case BPF_LD | BPF_MEM:
933 		case BPF_LDX | BPF_MEM:
934 			if (!(memvalid & (1 << filter[pc].k))) {
935 				ret = -EINVAL;
936 				goto error;
937 			}
938 			break;
939 		case BPF_JMP | BPF_JA:
940 			/* A jump must set masks on target */
941 			masks[pc + 1 + filter[pc].k] &= memvalid;
942 			memvalid = ~0;
943 			break;
944 		case BPF_JMP | BPF_JEQ | BPF_K:
945 		case BPF_JMP | BPF_JEQ | BPF_X:
946 		case BPF_JMP | BPF_JGE | BPF_K:
947 		case BPF_JMP | BPF_JGE | BPF_X:
948 		case BPF_JMP | BPF_JGT | BPF_K:
949 		case BPF_JMP | BPF_JGT | BPF_X:
950 		case BPF_JMP | BPF_JSET | BPF_K:
951 		case BPF_JMP | BPF_JSET | BPF_X:
952 			/* A jump must set masks on targets */
953 			masks[pc + 1 + filter[pc].jt] &= memvalid;
954 			masks[pc + 1 + filter[pc].jf] &= memvalid;
955 			memvalid = ~0;
956 			break;
957 		}
958 	}
959 error:
960 	kfree(masks);
961 	return ret;
962 }
963 
chk_code_allowed(u16 code_to_probe)964 static bool chk_code_allowed(u16 code_to_probe)
965 {
966 	static const bool codes[] = {
967 		/* 32 bit ALU operations */
968 		[BPF_ALU | BPF_ADD | BPF_K] = true,
969 		[BPF_ALU | BPF_ADD | BPF_X] = true,
970 		[BPF_ALU | BPF_SUB | BPF_K] = true,
971 		[BPF_ALU | BPF_SUB | BPF_X] = true,
972 		[BPF_ALU | BPF_MUL | BPF_K] = true,
973 		[BPF_ALU | BPF_MUL | BPF_X] = true,
974 		[BPF_ALU | BPF_DIV | BPF_K] = true,
975 		[BPF_ALU | BPF_DIV | BPF_X] = true,
976 		[BPF_ALU | BPF_MOD | BPF_K] = true,
977 		[BPF_ALU | BPF_MOD | BPF_X] = true,
978 		[BPF_ALU | BPF_AND | BPF_K] = true,
979 		[BPF_ALU | BPF_AND | BPF_X] = true,
980 		[BPF_ALU | BPF_OR | BPF_K] = true,
981 		[BPF_ALU | BPF_OR | BPF_X] = true,
982 		[BPF_ALU | BPF_XOR | BPF_K] = true,
983 		[BPF_ALU | BPF_XOR | BPF_X] = true,
984 		[BPF_ALU | BPF_LSH | BPF_K] = true,
985 		[BPF_ALU | BPF_LSH | BPF_X] = true,
986 		[BPF_ALU | BPF_RSH | BPF_K] = true,
987 		[BPF_ALU | BPF_RSH | BPF_X] = true,
988 		[BPF_ALU | BPF_NEG] = true,
989 		/* Load instructions */
990 		[BPF_LD | BPF_W | BPF_ABS] = true,
991 		[BPF_LD | BPF_H | BPF_ABS] = true,
992 		[BPF_LD | BPF_B | BPF_ABS] = true,
993 		[BPF_LD | BPF_W | BPF_LEN] = true,
994 		[BPF_LD | BPF_W | BPF_IND] = true,
995 		[BPF_LD | BPF_H | BPF_IND] = true,
996 		[BPF_LD | BPF_B | BPF_IND] = true,
997 		[BPF_LD | BPF_IMM] = true,
998 		[BPF_LD | BPF_MEM] = true,
999 		[BPF_LDX | BPF_W | BPF_LEN] = true,
1000 		[BPF_LDX | BPF_B | BPF_MSH] = true,
1001 		[BPF_LDX | BPF_IMM] = true,
1002 		[BPF_LDX | BPF_MEM] = true,
1003 		/* Store instructions */
1004 		[BPF_ST] = true,
1005 		[BPF_STX] = true,
1006 		/* Misc instructions */
1007 		[BPF_MISC | BPF_TAX] = true,
1008 		[BPF_MISC | BPF_TXA] = true,
1009 		/* Return instructions */
1010 		[BPF_RET | BPF_K] = true,
1011 		[BPF_RET | BPF_A] = true,
1012 		/* Jump instructions */
1013 		[BPF_JMP | BPF_JA] = true,
1014 		[BPF_JMP | BPF_JEQ | BPF_K] = true,
1015 		[BPF_JMP | BPF_JEQ | BPF_X] = true,
1016 		[BPF_JMP | BPF_JGE | BPF_K] = true,
1017 		[BPF_JMP | BPF_JGE | BPF_X] = true,
1018 		[BPF_JMP | BPF_JGT | BPF_K] = true,
1019 		[BPF_JMP | BPF_JGT | BPF_X] = true,
1020 		[BPF_JMP | BPF_JSET | BPF_K] = true,
1021 		[BPF_JMP | BPF_JSET | BPF_X] = true,
1022 	};
1023 
1024 	if (code_to_probe >= ARRAY_SIZE(codes))
1025 		return false;
1026 
1027 	return codes[code_to_probe];
1028 }
1029 
bpf_check_basics_ok(const struct sock_filter * filter,unsigned int flen)1030 static bool bpf_check_basics_ok(const struct sock_filter *filter,
1031 				unsigned int flen)
1032 {
1033 	if (filter == NULL)
1034 		return false;
1035 	if (flen == 0 || flen > BPF_MAXINSNS)
1036 		return false;
1037 
1038 	return true;
1039 }
1040 
1041 /**
1042  *	bpf_check_classic - verify socket filter code
1043  *	@filter: filter to verify
1044  *	@flen: length of filter
1045  *
1046  * Check the user's filter code. If we let some ugly
1047  * filter code slip through kaboom! The filter must contain
1048  * no references or jumps that are out of range, no illegal
1049  * instructions, and must end with a RET instruction.
1050  *
1051  * All jumps are forward as they are not signed.
1052  *
1053  * Returns 0 if the rule set is legal or -EINVAL if not.
1054  */
bpf_check_classic(const struct sock_filter * filter,unsigned int flen)1055 static int bpf_check_classic(const struct sock_filter *filter,
1056 			     unsigned int flen)
1057 {
1058 	bool anc_found;
1059 	int pc;
1060 
1061 	/* Check the filter code now */
1062 	for (pc = 0; pc < flen; pc++) {
1063 		const struct sock_filter *ftest = &filter[pc];
1064 
1065 		/* May we actually operate on this code? */
1066 		if (!chk_code_allowed(ftest->code))
1067 			return -EINVAL;
1068 
1069 		/* Some instructions need special checks */
1070 		switch (ftest->code) {
1071 		case BPF_ALU | BPF_DIV | BPF_K:
1072 		case BPF_ALU | BPF_MOD | BPF_K:
1073 			/* Check for division by zero */
1074 			if (ftest->k == 0)
1075 				return -EINVAL;
1076 			break;
1077 		case BPF_ALU | BPF_LSH | BPF_K:
1078 		case BPF_ALU | BPF_RSH | BPF_K:
1079 			if (ftest->k >= 32)
1080 				return -EINVAL;
1081 			break;
1082 		case BPF_LD | BPF_MEM:
1083 		case BPF_LDX | BPF_MEM:
1084 		case BPF_ST:
1085 		case BPF_STX:
1086 			/* Check for invalid memory addresses */
1087 			if (ftest->k >= BPF_MEMWORDS)
1088 				return -EINVAL;
1089 			break;
1090 		case BPF_JMP | BPF_JA:
1091 			/* Note, the large ftest->k might cause loops.
1092 			 * Compare this with conditional jumps below,
1093 			 * where offsets are limited. --ANK (981016)
1094 			 */
1095 			if (ftest->k >= (unsigned int)(flen - pc - 1))
1096 				return -EINVAL;
1097 			break;
1098 		case BPF_JMP | BPF_JEQ | BPF_K:
1099 		case BPF_JMP | BPF_JEQ | BPF_X:
1100 		case BPF_JMP | BPF_JGE | BPF_K:
1101 		case BPF_JMP | BPF_JGE | BPF_X:
1102 		case BPF_JMP | BPF_JGT | BPF_K:
1103 		case BPF_JMP | BPF_JGT | BPF_X:
1104 		case BPF_JMP | BPF_JSET | BPF_K:
1105 		case BPF_JMP | BPF_JSET | BPF_X:
1106 			/* Both conditionals must be safe */
1107 			if (pc + ftest->jt + 1 >= flen ||
1108 			    pc + ftest->jf + 1 >= flen)
1109 				return -EINVAL;
1110 			break;
1111 		case BPF_LD | BPF_W | BPF_ABS:
1112 		case BPF_LD | BPF_H | BPF_ABS:
1113 		case BPF_LD | BPF_B | BPF_ABS:
1114 			anc_found = false;
1115 			if (bpf_anc_helper(ftest) & BPF_ANC)
1116 				anc_found = true;
1117 			/* Ancillary operation unknown or unsupported */
1118 			if (anc_found == false && ftest->k >= SKF_AD_OFF)
1119 				return -EINVAL;
1120 		}
1121 	}
1122 
1123 	/* Last instruction must be a RET code */
1124 	switch (filter[flen - 1].code) {
1125 	case BPF_RET | BPF_K:
1126 	case BPF_RET | BPF_A:
1127 		return check_load_and_stores(filter, flen);
1128 	}
1129 
1130 	return -EINVAL;
1131 }
1132 
bpf_prog_store_orig_filter(struct bpf_prog * fp,const struct sock_fprog * fprog)1133 static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
1134 				      const struct sock_fprog *fprog)
1135 {
1136 	unsigned int fsize = bpf_classic_proglen(fprog);
1137 	struct sock_fprog_kern *fkprog;
1138 
1139 	fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
1140 	if (!fp->orig_prog)
1141 		return -ENOMEM;
1142 
1143 	fkprog = fp->orig_prog;
1144 	fkprog->len = fprog->len;
1145 
1146 	fkprog->filter = kmemdup(fp->insns, fsize,
1147 				 GFP_KERNEL | __GFP_NOWARN);
1148 	if (!fkprog->filter) {
1149 		kfree(fp->orig_prog);
1150 		return -ENOMEM;
1151 	}
1152 
1153 	return 0;
1154 }
1155 
bpf_release_orig_filter(struct bpf_prog * fp)1156 static void bpf_release_orig_filter(struct bpf_prog *fp)
1157 {
1158 	struct sock_fprog_kern *fprog = fp->orig_prog;
1159 
1160 	if (fprog) {
1161 		kfree(fprog->filter);
1162 		kfree(fprog);
1163 	}
1164 }
1165 
__bpf_prog_release(struct bpf_prog * prog)1166 static void __bpf_prog_release(struct bpf_prog *prog)
1167 {
1168 	if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
1169 		bpf_prog_put(prog);
1170 	} else {
1171 		bpf_release_orig_filter(prog);
1172 		bpf_prog_free(prog);
1173 	}
1174 }
1175 
__sk_filter_release(struct sk_filter * fp)1176 static void __sk_filter_release(struct sk_filter *fp)
1177 {
1178 	__bpf_prog_release(fp->prog);
1179 	kfree(fp);
1180 }
1181 
1182 /**
1183  * 	sk_filter_release_rcu - Release a socket filter by rcu_head
1184  *	@rcu: rcu_head that contains the sk_filter to free
1185  */
sk_filter_release_rcu(struct rcu_head * rcu)1186 static void sk_filter_release_rcu(struct rcu_head *rcu)
1187 {
1188 	struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
1189 
1190 	__sk_filter_release(fp);
1191 }
1192 
1193 /**
1194  *	sk_filter_release - release a socket filter
1195  *	@fp: filter to remove
1196  *
1197  *	Remove a filter from a socket and release its resources.
1198  */
sk_filter_release(struct sk_filter * fp)1199 static void sk_filter_release(struct sk_filter *fp)
1200 {
1201 	if (refcount_dec_and_test(&fp->refcnt))
1202 		call_rcu(&fp->rcu, sk_filter_release_rcu);
1203 }
1204 
sk_filter_uncharge(struct sock * sk,struct sk_filter * fp)1205 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1206 {
1207 	u32 filter_size = bpf_prog_size(fp->prog->len);
1208 
1209 	atomic_sub(filter_size, &sk->sk_omem_alloc);
1210 	sk_filter_release(fp);
1211 }
1212 
1213 /* try to charge the socket memory if there is space available
1214  * return true on success
1215  */
__sk_filter_charge(struct sock * sk,struct sk_filter * fp)1216 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1217 {
1218 	u32 filter_size = bpf_prog_size(fp->prog->len);
1219 	int optmem_max = READ_ONCE(sysctl_optmem_max);
1220 
1221 	/* same check as in sock_kmalloc() */
1222 	if (filter_size <= optmem_max &&
1223 	    atomic_read(&sk->sk_omem_alloc) + filter_size < optmem_max) {
1224 		atomic_add(filter_size, &sk->sk_omem_alloc);
1225 		return true;
1226 	}
1227 	return false;
1228 }
1229 
sk_filter_charge(struct sock * sk,struct sk_filter * fp)1230 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1231 {
1232 	if (!refcount_inc_not_zero(&fp->refcnt))
1233 		return false;
1234 
1235 	if (!__sk_filter_charge(sk, fp)) {
1236 		sk_filter_release(fp);
1237 		return false;
1238 	}
1239 	return true;
1240 }
1241 
bpf_migrate_filter(struct bpf_prog * fp)1242 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
1243 {
1244 	struct sock_filter *old_prog;
1245 	struct bpf_prog *old_fp;
1246 	int err, new_len, old_len = fp->len;
1247 	bool seen_ld_abs = false;
1248 
1249 	/* We are free to overwrite insns et al right here as it won't be used at
1250 	 * this point in time anymore internally after the migration to the eBPF
1251 	 * instruction representation.
1252 	 */
1253 	BUILD_BUG_ON(sizeof(struct sock_filter) !=
1254 		     sizeof(struct bpf_insn));
1255 
1256 	/* Conversion cannot happen on overlapping memory areas,
1257 	 * so we need to keep the user BPF around until the 2nd
1258 	 * pass. At this time, the user BPF is stored in fp->insns.
1259 	 */
1260 	old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
1261 			   GFP_KERNEL | __GFP_NOWARN);
1262 	if (!old_prog) {
1263 		err = -ENOMEM;
1264 		goto out_err;
1265 	}
1266 
1267 	/* 1st pass: calculate the new program length. */
1268 	err = bpf_convert_filter(old_prog, old_len, NULL, &new_len,
1269 				 &seen_ld_abs);
1270 	if (err)
1271 		goto out_err_free;
1272 
1273 	/* Expand fp for appending the new filter representation. */
1274 	old_fp = fp;
1275 	fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
1276 	if (!fp) {
1277 		/* The old_fp is still around in case we couldn't
1278 		 * allocate new memory, so uncharge on that one.
1279 		 */
1280 		fp = old_fp;
1281 		err = -ENOMEM;
1282 		goto out_err_free;
1283 	}
1284 
1285 	fp->len = new_len;
1286 
1287 	/* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1288 	err = bpf_convert_filter(old_prog, old_len, fp, &new_len,
1289 				 &seen_ld_abs);
1290 	if (err)
1291 		/* 2nd bpf_convert_filter() can fail only if it fails
1292 		 * to allocate memory, remapping must succeed. Note,
1293 		 * that at this time old_fp has already been released
1294 		 * by krealloc().
1295 		 */
1296 		goto out_err_free;
1297 
1298 	fp = bpf_prog_select_runtime(fp, &err);
1299 	if (err)
1300 		goto out_err_free;
1301 
1302 	kfree(old_prog);
1303 	return fp;
1304 
1305 out_err_free:
1306 	kfree(old_prog);
1307 out_err:
1308 	__bpf_prog_release(fp);
1309 	return ERR_PTR(err);
1310 }
1311 
bpf_prepare_filter(struct bpf_prog * fp,bpf_aux_classic_check_t trans)1312 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
1313 					   bpf_aux_classic_check_t trans)
1314 {
1315 	int err;
1316 
1317 	fp->bpf_func = NULL;
1318 	fp->jited = 0;
1319 
1320 	err = bpf_check_classic(fp->insns, fp->len);
1321 	if (err) {
1322 		__bpf_prog_release(fp);
1323 		return ERR_PTR(err);
1324 	}
1325 
1326 	/* There might be additional checks and transformations
1327 	 * needed on classic filters, f.e. in case of seccomp.
1328 	 */
1329 	if (trans) {
1330 		err = trans(fp->insns, fp->len);
1331 		if (err) {
1332 			__bpf_prog_release(fp);
1333 			return ERR_PTR(err);
1334 		}
1335 	}
1336 
1337 	/* Probe if we can JIT compile the filter and if so, do
1338 	 * the compilation of the filter.
1339 	 */
1340 	bpf_jit_compile(fp);
1341 
1342 	/* JIT compiler couldn't process this filter, so do the eBPF translation
1343 	 * for the optimized interpreter.
1344 	 */
1345 	if (!fp->jited)
1346 		fp = bpf_migrate_filter(fp);
1347 
1348 	return fp;
1349 }
1350 
1351 /**
1352  *	bpf_prog_create - create an unattached filter
1353  *	@pfp: the unattached filter that is created
1354  *	@fprog: the filter program
1355  *
1356  * Create a filter independent of any socket. We first run some
1357  * sanity checks on it to make sure it does not explode on us later.
1358  * If an error occurs or there is insufficient memory for the filter
1359  * a negative errno code is returned. On success the return is zero.
1360  */
bpf_prog_create(struct bpf_prog ** pfp,struct sock_fprog_kern * fprog)1361 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
1362 {
1363 	unsigned int fsize = bpf_classic_proglen(fprog);
1364 	struct bpf_prog *fp;
1365 
1366 	/* Make sure new filter is there and in the right amounts. */
1367 	if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1368 		return -EINVAL;
1369 
1370 	fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1371 	if (!fp)
1372 		return -ENOMEM;
1373 
1374 	memcpy(fp->insns, fprog->filter, fsize);
1375 
1376 	fp->len = fprog->len;
1377 	/* Since unattached filters are not copied back to user
1378 	 * space through sk_get_filter(), we do not need to hold
1379 	 * a copy here, and can spare us the work.
1380 	 */
1381 	fp->orig_prog = NULL;
1382 
1383 	/* bpf_prepare_filter() already takes care of freeing
1384 	 * memory in case something goes wrong.
1385 	 */
1386 	fp = bpf_prepare_filter(fp, NULL);
1387 	if (IS_ERR(fp))
1388 		return PTR_ERR(fp);
1389 
1390 	*pfp = fp;
1391 	return 0;
1392 }
1393 EXPORT_SYMBOL_GPL(bpf_prog_create);
1394 
1395 /**
1396  *	bpf_prog_create_from_user - create an unattached filter from user buffer
1397  *	@pfp: the unattached filter that is created
1398  *	@fprog: the filter program
1399  *	@trans: post-classic verifier transformation handler
1400  *	@save_orig: save classic BPF program
1401  *
1402  * This function effectively does the same as bpf_prog_create(), only
1403  * that it builds up its insns buffer from user space provided buffer.
1404  * It also allows for passing a bpf_aux_classic_check_t handler.
1405  */
bpf_prog_create_from_user(struct bpf_prog ** pfp,struct sock_fprog * fprog,bpf_aux_classic_check_t trans,bool save_orig)1406 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1407 			      bpf_aux_classic_check_t trans, bool save_orig)
1408 {
1409 	unsigned int fsize = bpf_classic_proglen(fprog);
1410 	struct bpf_prog *fp;
1411 	int err;
1412 
1413 	/* Make sure new filter is there and in the right amounts. */
1414 	if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1415 		return -EINVAL;
1416 
1417 	fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1418 	if (!fp)
1419 		return -ENOMEM;
1420 
1421 	if (copy_from_user(fp->insns, fprog->filter, fsize)) {
1422 		__bpf_prog_free(fp);
1423 		return -EFAULT;
1424 	}
1425 
1426 	fp->len = fprog->len;
1427 	fp->orig_prog = NULL;
1428 
1429 	if (save_orig) {
1430 		err = bpf_prog_store_orig_filter(fp, fprog);
1431 		if (err) {
1432 			__bpf_prog_free(fp);
1433 			return -ENOMEM;
1434 		}
1435 	}
1436 
1437 	/* bpf_prepare_filter() already takes care of freeing
1438 	 * memory in case something goes wrong.
1439 	 */
1440 	fp = bpf_prepare_filter(fp, trans);
1441 	if (IS_ERR(fp))
1442 		return PTR_ERR(fp);
1443 
1444 	*pfp = fp;
1445 	return 0;
1446 }
1447 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
1448 
bpf_prog_destroy(struct bpf_prog * fp)1449 void bpf_prog_destroy(struct bpf_prog *fp)
1450 {
1451 	__bpf_prog_release(fp);
1452 }
1453 EXPORT_SYMBOL_GPL(bpf_prog_destroy);
1454 
__sk_attach_prog(struct bpf_prog * prog,struct sock * sk)1455 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
1456 {
1457 	struct sk_filter *fp, *old_fp;
1458 
1459 	fp = kmalloc(sizeof(*fp), GFP_KERNEL);
1460 	if (!fp)
1461 		return -ENOMEM;
1462 
1463 	fp->prog = prog;
1464 
1465 	if (!__sk_filter_charge(sk, fp)) {
1466 		kfree(fp);
1467 		return -ENOMEM;
1468 	}
1469 	refcount_set(&fp->refcnt, 1);
1470 
1471 	old_fp = rcu_dereference_protected(sk->sk_filter,
1472 					   lockdep_sock_is_held(sk));
1473 	rcu_assign_pointer(sk->sk_filter, fp);
1474 
1475 	if (old_fp)
1476 		sk_filter_uncharge(sk, old_fp);
1477 
1478 	return 0;
1479 }
1480 
1481 static
__get_filter(struct sock_fprog * fprog,struct sock * sk)1482 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
1483 {
1484 	unsigned int fsize = bpf_classic_proglen(fprog);
1485 	struct bpf_prog *prog;
1486 	int err;
1487 
1488 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
1489 		return ERR_PTR(-EPERM);
1490 
1491 	/* Make sure new filter is there and in the right amounts. */
1492 	if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1493 		return ERR_PTR(-EINVAL);
1494 
1495 	prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1496 	if (!prog)
1497 		return ERR_PTR(-ENOMEM);
1498 
1499 	if (copy_from_user(prog->insns, fprog->filter, fsize)) {
1500 		__bpf_prog_free(prog);
1501 		return ERR_PTR(-EFAULT);
1502 	}
1503 
1504 	prog->len = fprog->len;
1505 
1506 	err = bpf_prog_store_orig_filter(prog, fprog);
1507 	if (err) {
1508 		__bpf_prog_free(prog);
1509 		return ERR_PTR(-ENOMEM);
1510 	}
1511 
1512 	/* bpf_prepare_filter() already takes care of freeing
1513 	 * memory in case something goes wrong.
1514 	 */
1515 	return bpf_prepare_filter(prog, NULL);
1516 }
1517 
1518 /**
1519  *	sk_attach_filter - attach a socket filter
1520  *	@fprog: the filter program
1521  *	@sk: the socket to use
1522  *
1523  * Attach the user's filter code. We first run some sanity checks on
1524  * it to make sure it does not explode on us later. If an error
1525  * occurs or there is insufficient memory for the filter a negative
1526  * errno code is returned. On success the return is zero.
1527  */
sk_attach_filter(struct sock_fprog * fprog,struct sock * sk)1528 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1529 {
1530 	struct bpf_prog *prog = __get_filter(fprog, sk);
1531 	int err;
1532 
1533 	if (IS_ERR(prog))
1534 		return PTR_ERR(prog);
1535 
1536 	err = __sk_attach_prog(prog, sk);
1537 	if (err < 0) {
1538 		__bpf_prog_release(prog);
1539 		return err;
1540 	}
1541 
1542 	return 0;
1543 }
1544 EXPORT_SYMBOL_GPL(sk_attach_filter);
1545 
sk_reuseport_attach_filter(struct sock_fprog * fprog,struct sock * sk)1546 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1547 {
1548 	struct bpf_prog *prog = __get_filter(fprog, sk);
1549 	int err;
1550 
1551 	if (IS_ERR(prog))
1552 		return PTR_ERR(prog);
1553 
1554 	if (bpf_prog_size(prog->len) > READ_ONCE(sysctl_optmem_max))
1555 		err = -ENOMEM;
1556 	else
1557 		err = reuseport_attach_prog(sk, prog);
1558 
1559 	if (err)
1560 		__bpf_prog_release(prog);
1561 
1562 	return err;
1563 }
1564 
__get_bpf(u32 ufd,struct sock * sk)1565 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
1566 {
1567 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
1568 		return ERR_PTR(-EPERM);
1569 
1570 	return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1571 }
1572 
sk_attach_bpf(u32 ufd,struct sock * sk)1573 int sk_attach_bpf(u32 ufd, struct sock *sk)
1574 {
1575 	struct bpf_prog *prog = __get_bpf(ufd, sk);
1576 	int err;
1577 
1578 	if (IS_ERR(prog))
1579 		return PTR_ERR(prog);
1580 
1581 	err = __sk_attach_prog(prog, sk);
1582 	if (err < 0) {
1583 		bpf_prog_put(prog);
1584 		return err;
1585 	}
1586 
1587 	return 0;
1588 }
1589 
sk_reuseport_attach_bpf(u32 ufd,struct sock * sk)1590 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
1591 {
1592 	struct bpf_prog *prog;
1593 	int err;
1594 
1595 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
1596 		return -EPERM;
1597 
1598 	prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1599 	if (PTR_ERR(prog) == -EINVAL)
1600 		prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SK_REUSEPORT);
1601 	if (IS_ERR(prog))
1602 		return PTR_ERR(prog);
1603 
1604 	if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) {
1605 		/* Like other non BPF_PROG_TYPE_SOCKET_FILTER
1606 		 * bpf prog (e.g. sockmap).  It depends on the
1607 		 * limitation imposed by bpf_prog_load().
1608 		 * Hence, sysctl_optmem_max is not checked.
1609 		 */
1610 		if ((sk->sk_type != SOCK_STREAM &&
1611 		     sk->sk_type != SOCK_DGRAM) ||
1612 		    (sk->sk_protocol != IPPROTO_UDP &&
1613 		     sk->sk_protocol != IPPROTO_TCP) ||
1614 		    (sk->sk_family != AF_INET &&
1615 		     sk->sk_family != AF_INET6)) {
1616 			err = -ENOTSUPP;
1617 			goto err_prog_put;
1618 		}
1619 	} else {
1620 		/* BPF_PROG_TYPE_SOCKET_FILTER */
1621 		if (bpf_prog_size(prog->len) > READ_ONCE(sysctl_optmem_max)) {
1622 			err = -ENOMEM;
1623 			goto err_prog_put;
1624 		}
1625 	}
1626 
1627 	err = reuseport_attach_prog(sk, prog);
1628 err_prog_put:
1629 	if (err)
1630 		bpf_prog_put(prog);
1631 
1632 	return err;
1633 }
1634 
sk_reuseport_prog_free(struct bpf_prog * prog)1635 void sk_reuseport_prog_free(struct bpf_prog *prog)
1636 {
1637 	if (!prog)
1638 		return;
1639 
1640 	if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT)
1641 		bpf_prog_put(prog);
1642 	else
1643 		bpf_prog_destroy(prog);
1644 }
1645 
1646 struct bpf_scratchpad {
1647 	union {
1648 		__be32 diff[MAX_BPF_STACK / sizeof(__be32)];
1649 		u8     buff[MAX_BPF_STACK];
1650 	};
1651 };
1652 
1653 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
1654 
__bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1655 static inline int __bpf_try_make_writable(struct sk_buff *skb,
1656 					  unsigned int write_len)
1657 {
1658 	return skb_ensure_writable(skb, write_len);
1659 }
1660 
bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1661 static inline int bpf_try_make_writable(struct sk_buff *skb,
1662 					unsigned int write_len)
1663 {
1664 	int err = __bpf_try_make_writable(skb, write_len);
1665 
1666 	bpf_compute_data_pointers(skb);
1667 	return err;
1668 }
1669 
bpf_try_make_head_writable(struct sk_buff * skb)1670 static int bpf_try_make_head_writable(struct sk_buff *skb)
1671 {
1672 	return bpf_try_make_writable(skb, skb_headlen(skb));
1673 }
1674 
bpf_push_mac_rcsum(struct sk_buff * skb)1675 static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
1676 {
1677 	if (skb_at_tc_ingress(skb))
1678 		skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1679 }
1680 
bpf_pull_mac_rcsum(struct sk_buff * skb)1681 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
1682 {
1683 	if (skb_at_tc_ingress(skb))
1684 		skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1685 }
1686 
BPF_CALL_5(bpf_skb_store_bytes,struct sk_buff *,skb,u32,offset,const void *,from,u32,len,u64,flags)1687 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
1688 	   const void *, from, u32, len, u64, flags)
1689 {
1690 	void *ptr;
1691 
1692 	if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
1693 		return -EINVAL;
1694 	if (unlikely(offset > INT_MAX))
1695 		return -EFAULT;
1696 	if (unlikely(bpf_try_make_writable(skb, offset + len)))
1697 		return -EFAULT;
1698 
1699 	ptr = skb->data + offset;
1700 	if (flags & BPF_F_RECOMPUTE_CSUM)
1701 		__skb_postpull_rcsum(skb, ptr, len, offset);
1702 
1703 	memcpy(ptr, from, len);
1704 
1705 	if (flags & BPF_F_RECOMPUTE_CSUM)
1706 		__skb_postpush_rcsum(skb, ptr, len, offset);
1707 	if (flags & BPF_F_INVALIDATE_HASH)
1708 		skb_clear_hash(skb);
1709 
1710 	return 0;
1711 }
1712 
1713 static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
1714 	.func		= bpf_skb_store_bytes,
1715 	.gpl_only	= false,
1716 	.ret_type	= RET_INTEGER,
1717 	.arg1_type	= ARG_PTR_TO_CTX,
1718 	.arg2_type	= ARG_ANYTHING,
1719 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
1720 	.arg4_type	= ARG_CONST_SIZE,
1721 	.arg5_type	= ARG_ANYTHING,
1722 };
1723 
BPF_CALL_4(bpf_skb_load_bytes,const struct sk_buff *,skb,u32,offset,void *,to,u32,len)1724 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
1725 	   void *, to, u32, len)
1726 {
1727 	void *ptr;
1728 
1729 	if (unlikely(offset > INT_MAX))
1730 		goto err_clear;
1731 
1732 	ptr = skb_header_pointer(skb, offset, len, to);
1733 	if (unlikely(!ptr))
1734 		goto err_clear;
1735 	if (ptr != to)
1736 		memcpy(to, ptr, len);
1737 
1738 	return 0;
1739 err_clear:
1740 	memset(to, 0, len);
1741 	return -EFAULT;
1742 }
1743 
1744 static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
1745 	.func		= bpf_skb_load_bytes,
1746 	.gpl_only	= false,
1747 	.ret_type	= RET_INTEGER,
1748 	.arg1_type	= ARG_PTR_TO_CTX,
1749 	.arg2_type	= ARG_ANYTHING,
1750 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
1751 	.arg4_type	= ARG_CONST_SIZE,
1752 };
1753 
BPF_CALL_4(bpf_flow_dissector_load_bytes,const struct bpf_flow_dissector *,ctx,u32,offset,void *,to,u32,len)1754 BPF_CALL_4(bpf_flow_dissector_load_bytes,
1755 	   const struct bpf_flow_dissector *, ctx, u32, offset,
1756 	   void *, to, u32, len)
1757 {
1758 	void *ptr;
1759 
1760 	if (unlikely(offset > 0xffff))
1761 		goto err_clear;
1762 
1763 	if (unlikely(!ctx->skb))
1764 		goto err_clear;
1765 
1766 	ptr = skb_header_pointer(ctx->skb, offset, len, to);
1767 	if (unlikely(!ptr))
1768 		goto err_clear;
1769 	if (ptr != to)
1770 		memcpy(to, ptr, len);
1771 
1772 	return 0;
1773 err_clear:
1774 	memset(to, 0, len);
1775 	return -EFAULT;
1776 }
1777 
1778 static const struct bpf_func_proto bpf_flow_dissector_load_bytes_proto = {
1779 	.func		= bpf_flow_dissector_load_bytes,
1780 	.gpl_only	= false,
1781 	.ret_type	= RET_INTEGER,
1782 	.arg1_type	= ARG_PTR_TO_CTX,
1783 	.arg2_type	= ARG_ANYTHING,
1784 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
1785 	.arg4_type	= ARG_CONST_SIZE,
1786 };
1787 
BPF_CALL_5(bpf_skb_load_bytes_relative,const struct sk_buff *,skb,u32,offset,void *,to,u32,len,u32,start_header)1788 BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb,
1789 	   u32, offset, void *, to, u32, len, u32, start_header)
1790 {
1791 	u8 *end = skb_tail_pointer(skb);
1792 	u8 *start, *ptr;
1793 
1794 	if (unlikely(offset > 0xffff))
1795 		goto err_clear;
1796 
1797 	switch (start_header) {
1798 	case BPF_HDR_START_MAC:
1799 		if (unlikely(!skb_mac_header_was_set(skb)))
1800 			goto err_clear;
1801 		start = skb_mac_header(skb);
1802 		break;
1803 	case BPF_HDR_START_NET:
1804 		start = skb_network_header(skb);
1805 		break;
1806 	default:
1807 		goto err_clear;
1808 	}
1809 
1810 	ptr = start + offset;
1811 
1812 	if (likely(ptr + len <= end)) {
1813 		memcpy(to, ptr, len);
1814 		return 0;
1815 	}
1816 
1817 err_clear:
1818 	memset(to, 0, len);
1819 	return -EFAULT;
1820 }
1821 
1822 static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = {
1823 	.func		= bpf_skb_load_bytes_relative,
1824 	.gpl_only	= false,
1825 	.ret_type	= RET_INTEGER,
1826 	.arg1_type	= ARG_PTR_TO_CTX,
1827 	.arg2_type	= ARG_ANYTHING,
1828 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
1829 	.arg4_type	= ARG_CONST_SIZE,
1830 	.arg5_type	= ARG_ANYTHING,
1831 };
1832 
BPF_CALL_2(bpf_skb_pull_data,struct sk_buff *,skb,u32,len)1833 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
1834 {
1835 	/* Idea is the following: should the needed direct read/write
1836 	 * test fail during runtime, we can pull in more data and redo
1837 	 * again, since implicitly, we invalidate previous checks here.
1838 	 *
1839 	 * Or, since we know how much we need to make read/writeable,
1840 	 * this can be done once at the program beginning for direct
1841 	 * access case. By this we overcome limitations of only current
1842 	 * headroom being accessible.
1843 	 */
1844 	return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
1845 }
1846 
1847 static const struct bpf_func_proto bpf_skb_pull_data_proto = {
1848 	.func		= bpf_skb_pull_data,
1849 	.gpl_only	= false,
1850 	.ret_type	= RET_INTEGER,
1851 	.arg1_type	= ARG_PTR_TO_CTX,
1852 	.arg2_type	= ARG_ANYTHING,
1853 };
1854 
BPF_CALL_1(bpf_sk_fullsock,struct sock *,sk)1855 BPF_CALL_1(bpf_sk_fullsock, struct sock *, sk)
1856 {
1857 	return sk_fullsock(sk) ? (unsigned long)sk : (unsigned long)NULL;
1858 }
1859 
1860 static const struct bpf_func_proto bpf_sk_fullsock_proto = {
1861 	.func		= bpf_sk_fullsock,
1862 	.gpl_only	= false,
1863 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
1864 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
1865 };
1866 
sk_skb_try_make_writable(struct sk_buff * skb,unsigned int write_len)1867 static inline int sk_skb_try_make_writable(struct sk_buff *skb,
1868 					   unsigned int write_len)
1869 {
1870 	return __bpf_try_make_writable(skb, write_len);
1871 }
1872 
BPF_CALL_2(sk_skb_pull_data,struct sk_buff *,skb,u32,len)1873 BPF_CALL_2(sk_skb_pull_data, struct sk_buff *, skb, u32, len)
1874 {
1875 	/* Idea is the following: should the needed direct read/write
1876 	 * test fail during runtime, we can pull in more data and redo
1877 	 * again, since implicitly, we invalidate previous checks here.
1878 	 *
1879 	 * Or, since we know how much we need to make read/writeable,
1880 	 * this can be done once at the program beginning for direct
1881 	 * access case. By this we overcome limitations of only current
1882 	 * headroom being accessible.
1883 	 */
1884 	return sk_skb_try_make_writable(skb, len ? : skb_headlen(skb));
1885 }
1886 
1887 static const struct bpf_func_proto sk_skb_pull_data_proto = {
1888 	.func		= sk_skb_pull_data,
1889 	.gpl_only	= false,
1890 	.ret_type	= RET_INTEGER,
1891 	.arg1_type	= ARG_PTR_TO_CTX,
1892 	.arg2_type	= ARG_ANYTHING,
1893 };
1894 
BPF_CALL_5(bpf_l3_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1895 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
1896 	   u64, from, u64, to, u64, flags)
1897 {
1898 	__sum16 *ptr;
1899 
1900 	if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
1901 		return -EINVAL;
1902 	if (unlikely(offset > 0xffff || offset & 1))
1903 		return -EFAULT;
1904 	if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1905 		return -EFAULT;
1906 
1907 	ptr = (__sum16 *)(skb->data + offset);
1908 	switch (flags & BPF_F_HDR_FIELD_MASK) {
1909 	case 0:
1910 		if (unlikely(from != 0))
1911 			return -EINVAL;
1912 
1913 		csum_replace_by_diff(ptr, to);
1914 		break;
1915 	case 2:
1916 		csum_replace2(ptr, from, to);
1917 		break;
1918 	case 4:
1919 		csum_replace4(ptr, from, to);
1920 		break;
1921 	default:
1922 		return -EINVAL;
1923 	}
1924 
1925 	return 0;
1926 }
1927 
1928 static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
1929 	.func		= bpf_l3_csum_replace,
1930 	.gpl_only	= false,
1931 	.ret_type	= RET_INTEGER,
1932 	.arg1_type	= ARG_PTR_TO_CTX,
1933 	.arg2_type	= ARG_ANYTHING,
1934 	.arg3_type	= ARG_ANYTHING,
1935 	.arg4_type	= ARG_ANYTHING,
1936 	.arg5_type	= ARG_ANYTHING,
1937 };
1938 
BPF_CALL_5(bpf_l4_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1939 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
1940 	   u64, from, u64, to, u64, flags)
1941 {
1942 	bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
1943 	bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
1944 	bool do_mforce = flags & BPF_F_MARK_ENFORCE;
1945 	__sum16 *ptr;
1946 
1947 	if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
1948 			       BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
1949 		return -EINVAL;
1950 	if (unlikely(offset > 0xffff || offset & 1))
1951 		return -EFAULT;
1952 	if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1953 		return -EFAULT;
1954 
1955 	ptr = (__sum16 *)(skb->data + offset);
1956 	if (is_mmzero && !do_mforce && !*ptr)
1957 		return 0;
1958 
1959 	switch (flags & BPF_F_HDR_FIELD_MASK) {
1960 	case 0:
1961 		if (unlikely(from != 0))
1962 			return -EINVAL;
1963 
1964 		inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
1965 		break;
1966 	case 2:
1967 		inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
1968 		break;
1969 	case 4:
1970 		inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
1971 		break;
1972 	default:
1973 		return -EINVAL;
1974 	}
1975 
1976 	if (is_mmzero && !*ptr)
1977 		*ptr = CSUM_MANGLED_0;
1978 	return 0;
1979 }
1980 
1981 static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
1982 	.func		= bpf_l4_csum_replace,
1983 	.gpl_only	= false,
1984 	.ret_type	= RET_INTEGER,
1985 	.arg1_type	= ARG_PTR_TO_CTX,
1986 	.arg2_type	= ARG_ANYTHING,
1987 	.arg3_type	= ARG_ANYTHING,
1988 	.arg4_type	= ARG_ANYTHING,
1989 	.arg5_type	= ARG_ANYTHING,
1990 };
1991 
BPF_CALL_5(bpf_csum_diff,__be32 *,from,u32,from_size,__be32 *,to,u32,to_size,__wsum,seed)1992 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
1993 	   __be32 *, to, u32, to_size, __wsum, seed)
1994 {
1995 	struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
1996 	u32 diff_size = from_size + to_size;
1997 	int i, j = 0;
1998 
1999 	/* This is quite flexible, some examples:
2000 	 *
2001 	 * from_size == 0, to_size > 0,  seed := csum --> pushing data
2002 	 * from_size > 0,  to_size == 0, seed := csum --> pulling data
2003 	 * from_size > 0,  to_size > 0,  seed := 0    --> diffing data
2004 	 *
2005 	 * Even for diffing, from_size and to_size don't need to be equal.
2006 	 */
2007 	if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
2008 		     diff_size > sizeof(sp->diff)))
2009 		return -EINVAL;
2010 
2011 	for (i = 0; i < from_size / sizeof(__be32); i++, j++)
2012 		sp->diff[j] = ~from[i];
2013 	for (i = 0; i <   to_size / sizeof(__be32); i++, j++)
2014 		sp->diff[j] = to[i];
2015 
2016 	return csum_partial(sp->diff, diff_size, seed);
2017 }
2018 
2019 static const struct bpf_func_proto bpf_csum_diff_proto = {
2020 	.func		= bpf_csum_diff,
2021 	.gpl_only	= false,
2022 	.pkt_access	= true,
2023 	.ret_type	= RET_INTEGER,
2024 	.arg1_type	= ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2025 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
2026 	.arg3_type	= ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2027 	.arg4_type	= ARG_CONST_SIZE_OR_ZERO,
2028 	.arg5_type	= ARG_ANYTHING,
2029 };
2030 
BPF_CALL_2(bpf_csum_update,struct sk_buff *,skb,__wsum,csum)2031 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
2032 {
2033 	/* The interface is to be used in combination with bpf_csum_diff()
2034 	 * for direct packet writes. csum rotation for alignment as well
2035 	 * as emulating csum_sub() can be done from the eBPF program.
2036 	 */
2037 	if (skb->ip_summed == CHECKSUM_COMPLETE)
2038 		return (skb->csum = csum_add(skb->csum, csum));
2039 
2040 	return -ENOTSUPP;
2041 }
2042 
2043 static const struct bpf_func_proto bpf_csum_update_proto = {
2044 	.func		= bpf_csum_update,
2045 	.gpl_only	= false,
2046 	.ret_type	= RET_INTEGER,
2047 	.arg1_type	= ARG_PTR_TO_CTX,
2048 	.arg2_type	= ARG_ANYTHING,
2049 };
2050 
BPF_CALL_2(bpf_csum_level,struct sk_buff *,skb,u64,level)2051 BPF_CALL_2(bpf_csum_level, struct sk_buff *, skb, u64, level)
2052 {
2053 	/* The interface is to be used in combination with bpf_skb_adjust_room()
2054 	 * for encap/decap of packet headers when BPF_F_ADJ_ROOM_NO_CSUM_RESET
2055 	 * is passed as flags, for example.
2056 	 */
2057 	switch (level) {
2058 	case BPF_CSUM_LEVEL_INC:
2059 		__skb_incr_checksum_unnecessary(skb);
2060 		break;
2061 	case BPF_CSUM_LEVEL_DEC:
2062 		__skb_decr_checksum_unnecessary(skb);
2063 		break;
2064 	case BPF_CSUM_LEVEL_RESET:
2065 		__skb_reset_checksum_unnecessary(skb);
2066 		break;
2067 	case BPF_CSUM_LEVEL_QUERY:
2068 		return skb->ip_summed == CHECKSUM_UNNECESSARY ?
2069 		       skb->csum_level : -EACCES;
2070 	default:
2071 		return -EINVAL;
2072 	}
2073 
2074 	return 0;
2075 }
2076 
2077 static const struct bpf_func_proto bpf_csum_level_proto = {
2078 	.func		= bpf_csum_level,
2079 	.gpl_only	= false,
2080 	.ret_type	= RET_INTEGER,
2081 	.arg1_type	= ARG_PTR_TO_CTX,
2082 	.arg2_type	= ARG_ANYTHING,
2083 };
2084 
__bpf_rx_skb(struct net_device * dev,struct sk_buff * skb)2085 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
2086 {
2087 	return dev_forward_skb_nomtu(dev, skb);
2088 }
2089 
__bpf_rx_skb_no_mac(struct net_device * dev,struct sk_buff * skb)2090 static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
2091 				      struct sk_buff *skb)
2092 {
2093 	int ret = ____dev_forward_skb(dev, skb, false);
2094 
2095 	if (likely(!ret)) {
2096 		skb->dev = dev;
2097 		ret = netif_rx(skb);
2098 	}
2099 
2100 	return ret;
2101 }
2102 
__bpf_tx_skb(struct net_device * dev,struct sk_buff * skb)2103 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
2104 {
2105 	int ret;
2106 
2107 	if (dev_xmit_recursion()) {
2108 		net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2109 		kfree_skb(skb);
2110 		return -ENETDOWN;
2111 	}
2112 
2113 	skb->dev = dev;
2114 	skb_clear_tstamp(skb);
2115 
2116 	dev_xmit_recursion_inc();
2117 	ret = dev_queue_xmit(skb);
2118 	dev_xmit_recursion_dec();
2119 
2120 	return ret;
2121 }
2122 
__bpf_redirect_no_mac(struct sk_buff * skb,struct net_device * dev,u32 flags)2123 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
2124 				 u32 flags)
2125 {
2126 	unsigned int mlen = skb_network_offset(skb);
2127 
2128 	if (unlikely(skb->len <= mlen)) {
2129 		kfree_skb(skb);
2130 		return -ERANGE;
2131 	}
2132 
2133 	if (mlen) {
2134 		__skb_pull(skb, mlen);
2135 		if (unlikely(!skb->len)) {
2136 			kfree_skb(skb);
2137 			return -ERANGE;
2138 		}
2139 
2140 		/* At ingress, the mac header has already been pulled once.
2141 		 * At egress, skb_pospull_rcsum has to be done in case that
2142 		 * the skb is originated from ingress (i.e. a forwarded skb)
2143 		 * to ensure that rcsum starts at net header.
2144 		 */
2145 		if (!skb_at_tc_ingress(skb))
2146 			skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
2147 	}
2148 	skb_pop_mac_header(skb);
2149 	skb_reset_mac_len(skb);
2150 	return flags & BPF_F_INGRESS ?
2151 	       __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
2152 }
2153 
__bpf_redirect_common(struct sk_buff * skb,struct net_device * dev,u32 flags)2154 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
2155 				 u32 flags)
2156 {
2157 	/* Verify that a link layer header is carried */
2158 	if (unlikely(skb->mac_header >= skb->network_header || skb->len == 0)) {
2159 		kfree_skb(skb);
2160 		return -ERANGE;
2161 	}
2162 
2163 	bpf_push_mac_rcsum(skb);
2164 	return flags & BPF_F_INGRESS ?
2165 	       __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
2166 }
2167 
__bpf_redirect(struct sk_buff * skb,struct net_device * dev,u32 flags)2168 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
2169 			  u32 flags)
2170 {
2171 	if (dev_is_mac_header_xmit(dev))
2172 		return __bpf_redirect_common(skb, dev, flags);
2173 	else
2174 		return __bpf_redirect_no_mac(skb, dev, flags);
2175 }
2176 
2177 #if IS_ENABLED(CONFIG_IPV6)
bpf_out_neigh_v6(struct net * net,struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2178 static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb,
2179 			    struct net_device *dev, struct bpf_nh_params *nh)
2180 {
2181 	u32 hh_len = LL_RESERVED_SPACE(dev);
2182 	const struct in6_addr *nexthop;
2183 	struct dst_entry *dst = NULL;
2184 	struct neighbour *neigh;
2185 
2186 	if (dev_xmit_recursion()) {
2187 		net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2188 		goto out_drop;
2189 	}
2190 
2191 	skb->dev = dev;
2192 	skb_clear_tstamp(skb);
2193 
2194 	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
2195 		skb = skb_expand_head(skb, hh_len);
2196 		if (!skb)
2197 			return -ENOMEM;
2198 	}
2199 
2200 	rcu_read_lock_bh();
2201 	if (!nh) {
2202 		dst = skb_dst(skb);
2203 		nexthop = rt6_nexthop(container_of(dst, struct rt6_info, dst),
2204 				      &ipv6_hdr(skb)->daddr);
2205 	} else {
2206 		nexthop = &nh->ipv6_nh;
2207 	}
2208 	neigh = ip_neigh_gw6(dev, nexthop);
2209 	if (likely(!IS_ERR(neigh))) {
2210 		int ret;
2211 
2212 		sock_confirm_neigh(skb, neigh);
2213 		dev_xmit_recursion_inc();
2214 		ret = neigh_output(neigh, skb, false);
2215 		dev_xmit_recursion_dec();
2216 		rcu_read_unlock_bh();
2217 		return ret;
2218 	}
2219 	rcu_read_unlock_bh();
2220 	if (dst)
2221 		IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
2222 out_drop:
2223 	kfree_skb(skb);
2224 	return -ENETDOWN;
2225 }
2226 
__bpf_redirect_neigh_v6(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2227 static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
2228 				   struct bpf_nh_params *nh)
2229 {
2230 	const struct ipv6hdr *ip6h = ipv6_hdr(skb);
2231 	struct net *net = dev_net(dev);
2232 	int err, ret = NET_XMIT_DROP;
2233 
2234 	if (!nh) {
2235 		struct dst_entry *dst;
2236 		struct flowi6 fl6 = {
2237 			.flowi6_flags = FLOWI_FLAG_ANYSRC,
2238 			.flowi6_mark  = skb->mark,
2239 			.flowlabel    = ip6_flowinfo(ip6h),
2240 			.flowi6_oif   = dev->ifindex,
2241 			.flowi6_proto = ip6h->nexthdr,
2242 			.daddr	      = ip6h->daddr,
2243 			.saddr	      = ip6h->saddr,
2244 		};
2245 
2246 		dst = ipv6_stub->ipv6_dst_lookup_flow(net, NULL, &fl6, NULL);
2247 		if (IS_ERR(dst))
2248 			goto out_drop;
2249 
2250 		skb_dst_set(skb, dst);
2251 	} else if (nh->nh_family != AF_INET6) {
2252 		goto out_drop;
2253 	}
2254 
2255 	err = bpf_out_neigh_v6(net, skb, dev, nh);
2256 	if (unlikely(net_xmit_eval(err)))
2257 		dev->stats.tx_errors++;
2258 	else
2259 		ret = NET_XMIT_SUCCESS;
2260 	goto out_xmit;
2261 out_drop:
2262 	dev->stats.tx_errors++;
2263 	kfree_skb(skb);
2264 out_xmit:
2265 	return ret;
2266 }
2267 #else
__bpf_redirect_neigh_v6(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2268 static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
2269 				   struct bpf_nh_params *nh)
2270 {
2271 	kfree_skb(skb);
2272 	return NET_XMIT_DROP;
2273 }
2274 #endif /* CONFIG_IPV6 */
2275 
2276 #if IS_ENABLED(CONFIG_INET)
bpf_out_neigh_v4(struct net * net,struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2277 static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb,
2278 			    struct net_device *dev, struct bpf_nh_params *nh)
2279 {
2280 	u32 hh_len = LL_RESERVED_SPACE(dev);
2281 	struct neighbour *neigh;
2282 	bool is_v6gw = false;
2283 
2284 	if (dev_xmit_recursion()) {
2285 		net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2286 		goto out_drop;
2287 	}
2288 
2289 	skb->dev = dev;
2290 	skb_clear_tstamp(skb);
2291 
2292 	if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
2293 		skb = skb_expand_head(skb, hh_len);
2294 		if (!skb)
2295 			return -ENOMEM;
2296 	}
2297 
2298 	rcu_read_lock_bh();
2299 	if (!nh) {
2300 		struct dst_entry *dst = skb_dst(skb);
2301 		struct rtable *rt = container_of(dst, struct rtable, dst);
2302 
2303 		neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
2304 	} else if (nh->nh_family == AF_INET6) {
2305 		neigh = ip_neigh_gw6(dev, &nh->ipv6_nh);
2306 		is_v6gw = true;
2307 	} else if (nh->nh_family == AF_INET) {
2308 		neigh = ip_neigh_gw4(dev, nh->ipv4_nh);
2309 	} else {
2310 		rcu_read_unlock_bh();
2311 		goto out_drop;
2312 	}
2313 
2314 	if (likely(!IS_ERR(neigh))) {
2315 		int ret;
2316 
2317 		sock_confirm_neigh(skb, neigh);
2318 		dev_xmit_recursion_inc();
2319 		ret = neigh_output(neigh, skb, is_v6gw);
2320 		dev_xmit_recursion_dec();
2321 		rcu_read_unlock_bh();
2322 		return ret;
2323 	}
2324 	rcu_read_unlock_bh();
2325 out_drop:
2326 	kfree_skb(skb);
2327 	return -ENETDOWN;
2328 }
2329 
__bpf_redirect_neigh_v4(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2330 static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
2331 				   struct bpf_nh_params *nh)
2332 {
2333 	const struct iphdr *ip4h = ip_hdr(skb);
2334 	struct net *net = dev_net(dev);
2335 	int err, ret = NET_XMIT_DROP;
2336 
2337 	if (!nh) {
2338 		struct flowi4 fl4 = {
2339 			.flowi4_flags = FLOWI_FLAG_ANYSRC,
2340 			.flowi4_mark  = skb->mark,
2341 			.flowi4_tos   = RT_TOS(ip4h->tos),
2342 			.flowi4_oif   = dev->ifindex,
2343 			.flowi4_proto = ip4h->protocol,
2344 			.daddr	      = ip4h->daddr,
2345 			.saddr	      = ip4h->saddr,
2346 		};
2347 		struct rtable *rt;
2348 
2349 		rt = ip_route_output_flow(net, &fl4, NULL);
2350 		if (IS_ERR(rt))
2351 			goto out_drop;
2352 		if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
2353 			ip_rt_put(rt);
2354 			goto out_drop;
2355 		}
2356 
2357 		skb_dst_set(skb, &rt->dst);
2358 	}
2359 
2360 	err = bpf_out_neigh_v4(net, skb, dev, nh);
2361 	if (unlikely(net_xmit_eval(err)))
2362 		dev->stats.tx_errors++;
2363 	else
2364 		ret = NET_XMIT_SUCCESS;
2365 	goto out_xmit;
2366 out_drop:
2367 	dev->stats.tx_errors++;
2368 	kfree_skb(skb);
2369 out_xmit:
2370 	return ret;
2371 }
2372 #else
__bpf_redirect_neigh_v4(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2373 static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
2374 				   struct bpf_nh_params *nh)
2375 {
2376 	kfree_skb(skb);
2377 	return NET_XMIT_DROP;
2378 }
2379 #endif /* CONFIG_INET */
2380 
__bpf_redirect_neigh(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2381 static int __bpf_redirect_neigh(struct sk_buff *skb, struct net_device *dev,
2382 				struct bpf_nh_params *nh)
2383 {
2384 	struct ethhdr *ethh = eth_hdr(skb);
2385 
2386 	if (unlikely(skb->mac_header >= skb->network_header))
2387 		goto out;
2388 	bpf_push_mac_rcsum(skb);
2389 	if (is_multicast_ether_addr(ethh->h_dest))
2390 		goto out;
2391 
2392 	skb_pull(skb, sizeof(*ethh));
2393 	skb_unset_mac_header(skb);
2394 	skb_reset_network_header(skb);
2395 
2396 	if (skb->protocol == htons(ETH_P_IP))
2397 		return __bpf_redirect_neigh_v4(skb, dev, nh);
2398 	else if (skb->protocol == htons(ETH_P_IPV6))
2399 		return __bpf_redirect_neigh_v6(skb, dev, nh);
2400 out:
2401 	kfree_skb(skb);
2402 	return -ENOTSUPP;
2403 }
2404 
2405 /* Internal, non-exposed redirect flags. */
2406 enum {
2407 	BPF_F_NEIGH	= (1ULL << 1),
2408 	BPF_F_PEER	= (1ULL << 2),
2409 	BPF_F_NEXTHOP	= (1ULL << 3),
2410 #define BPF_F_REDIRECT_INTERNAL	(BPF_F_NEIGH | BPF_F_PEER | BPF_F_NEXTHOP)
2411 };
2412 
BPF_CALL_3(bpf_clone_redirect,struct sk_buff *,skb,u32,ifindex,u64,flags)2413 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
2414 {
2415 	struct net_device *dev;
2416 	struct sk_buff *clone;
2417 	int ret;
2418 
2419 	if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
2420 		return -EINVAL;
2421 
2422 	dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
2423 	if (unlikely(!dev))
2424 		return -EINVAL;
2425 
2426 	clone = skb_clone(skb, GFP_ATOMIC);
2427 	if (unlikely(!clone))
2428 		return -ENOMEM;
2429 
2430 	/* For direct write, we need to keep the invariant that the skbs
2431 	 * we're dealing with need to be uncloned. Should uncloning fail
2432 	 * here, we need to free the just generated clone to unclone once
2433 	 * again.
2434 	 */
2435 	ret = bpf_try_make_head_writable(skb);
2436 	if (unlikely(ret)) {
2437 		kfree_skb(clone);
2438 		return -ENOMEM;
2439 	}
2440 
2441 	return __bpf_redirect(clone, dev, flags);
2442 }
2443 
2444 static const struct bpf_func_proto bpf_clone_redirect_proto = {
2445 	.func           = bpf_clone_redirect,
2446 	.gpl_only       = false,
2447 	.ret_type       = RET_INTEGER,
2448 	.arg1_type      = ARG_PTR_TO_CTX,
2449 	.arg2_type      = ARG_ANYTHING,
2450 	.arg3_type      = ARG_ANYTHING,
2451 };
2452 
2453 DEFINE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
2454 EXPORT_PER_CPU_SYMBOL_GPL(bpf_redirect_info);
2455 
skb_do_redirect(struct sk_buff * skb)2456 int skb_do_redirect(struct sk_buff *skb)
2457 {
2458 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2459 	struct net *net = dev_net(skb->dev);
2460 	struct net_device *dev;
2461 	u32 flags = ri->flags;
2462 
2463 	dev = dev_get_by_index_rcu(net, ri->tgt_index);
2464 	ri->tgt_index = 0;
2465 	ri->flags = 0;
2466 	if (unlikely(!dev))
2467 		goto out_drop;
2468 	if (flags & BPF_F_PEER) {
2469 		const struct net_device_ops *ops = dev->netdev_ops;
2470 
2471 		if (unlikely(!ops->ndo_get_peer_dev ||
2472 			     !skb_at_tc_ingress(skb)))
2473 			goto out_drop;
2474 		dev = ops->ndo_get_peer_dev(dev);
2475 		if (unlikely(!dev ||
2476 			     !(dev->flags & IFF_UP) ||
2477 			     net_eq(net, dev_net(dev))))
2478 			goto out_drop;
2479 		skb->dev = dev;
2480 		return -EAGAIN;
2481 	}
2482 	return flags & BPF_F_NEIGH ?
2483 	       __bpf_redirect_neigh(skb, dev, flags & BPF_F_NEXTHOP ?
2484 				    &ri->nh : NULL) :
2485 	       __bpf_redirect(skb, dev, flags);
2486 out_drop:
2487 	kfree_skb(skb);
2488 	return -EINVAL;
2489 }
2490 
BPF_CALL_2(bpf_redirect,u32,ifindex,u64,flags)2491 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
2492 {
2493 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2494 
2495 	if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
2496 		return TC_ACT_SHOT;
2497 
2498 	ri->flags = flags;
2499 	ri->tgt_index = ifindex;
2500 
2501 	return TC_ACT_REDIRECT;
2502 }
2503 
2504 static const struct bpf_func_proto bpf_redirect_proto = {
2505 	.func           = bpf_redirect,
2506 	.gpl_only       = false,
2507 	.ret_type       = RET_INTEGER,
2508 	.arg1_type      = ARG_ANYTHING,
2509 	.arg2_type      = ARG_ANYTHING,
2510 };
2511 
BPF_CALL_2(bpf_redirect_peer,u32,ifindex,u64,flags)2512 BPF_CALL_2(bpf_redirect_peer, u32, ifindex, u64, flags)
2513 {
2514 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2515 
2516 	if (unlikely(flags))
2517 		return TC_ACT_SHOT;
2518 
2519 	ri->flags = BPF_F_PEER;
2520 	ri->tgt_index = ifindex;
2521 
2522 	return TC_ACT_REDIRECT;
2523 }
2524 
2525 static const struct bpf_func_proto bpf_redirect_peer_proto = {
2526 	.func           = bpf_redirect_peer,
2527 	.gpl_only       = false,
2528 	.ret_type       = RET_INTEGER,
2529 	.arg1_type      = ARG_ANYTHING,
2530 	.arg2_type      = ARG_ANYTHING,
2531 };
2532 
BPF_CALL_4(bpf_redirect_neigh,u32,ifindex,struct bpf_redir_neigh *,params,int,plen,u64,flags)2533 BPF_CALL_4(bpf_redirect_neigh, u32, ifindex, struct bpf_redir_neigh *, params,
2534 	   int, plen, u64, flags)
2535 {
2536 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2537 
2538 	if (unlikely((plen && plen < sizeof(*params)) || flags))
2539 		return TC_ACT_SHOT;
2540 
2541 	ri->flags = BPF_F_NEIGH | (plen ? BPF_F_NEXTHOP : 0);
2542 	ri->tgt_index = ifindex;
2543 
2544 	BUILD_BUG_ON(sizeof(struct bpf_redir_neigh) != sizeof(struct bpf_nh_params));
2545 	if (plen)
2546 		memcpy(&ri->nh, params, sizeof(ri->nh));
2547 
2548 	return TC_ACT_REDIRECT;
2549 }
2550 
2551 static const struct bpf_func_proto bpf_redirect_neigh_proto = {
2552 	.func		= bpf_redirect_neigh,
2553 	.gpl_only	= false,
2554 	.ret_type	= RET_INTEGER,
2555 	.arg1_type	= ARG_ANYTHING,
2556 	.arg2_type      = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2557 	.arg3_type      = ARG_CONST_SIZE_OR_ZERO,
2558 	.arg4_type	= ARG_ANYTHING,
2559 };
2560 
BPF_CALL_2(bpf_msg_apply_bytes,struct sk_msg *,msg,u32,bytes)2561 BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg *, msg, u32, bytes)
2562 {
2563 	msg->apply_bytes = bytes;
2564 	return 0;
2565 }
2566 
2567 static const struct bpf_func_proto bpf_msg_apply_bytes_proto = {
2568 	.func           = bpf_msg_apply_bytes,
2569 	.gpl_only       = false,
2570 	.ret_type       = RET_INTEGER,
2571 	.arg1_type	= ARG_PTR_TO_CTX,
2572 	.arg2_type      = ARG_ANYTHING,
2573 };
2574 
BPF_CALL_2(bpf_msg_cork_bytes,struct sk_msg *,msg,u32,bytes)2575 BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg *, msg, u32, bytes)
2576 {
2577 	msg->cork_bytes = bytes;
2578 	return 0;
2579 }
2580 
2581 static const struct bpf_func_proto bpf_msg_cork_bytes_proto = {
2582 	.func           = bpf_msg_cork_bytes,
2583 	.gpl_only       = false,
2584 	.ret_type       = RET_INTEGER,
2585 	.arg1_type	= ARG_PTR_TO_CTX,
2586 	.arg2_type      = ARG_ANYTHING,
2587 };
2588 
BPF_CALL_4(bpf_msg_pull_data,struct sk_msg *,msg,u32,start,u32,end,u64,flags)2589 BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start,
2590 	   u32, end, u64, flags)
2591 {
2592 	u32 len = 0, offset = 0, copy = 0, poffset = 0, bytes = end - start;
2593 	u32 first_sge, last_sge, i, shift, bytes_sg_total;
2594 	struct scatterlist *sge;
2595 	u8 *raw, *to, *from;
2596 	struct page *page;
2597 
2598 	if (unlikely(flags || end <= start))
2599 		return -EINVAL;
2600 
2601 	/* First find the starting scatterlist element */
2602 	i = msg->sg.start;
2603 	do {
2604 		offset += len;
2605 		len = sk_msg_elem(msg, i)->length;
2606 		if (start < offset + len)
2607 			break;
2608 		sk_msg_iter_var_next(i);
2609 	} while (i != msg->sg.end);
2610 
2611 	if (unlikely(start >= offset + len))
2612 		return -EINVAL;
2613 
2614 	first_sge = i;
2615 	/* The start may point into the sg element so we need to also
2616 	 * account for the headroom.
2617 	 */
2618 	bytes_sg_total = start - offset + bytes;
2619 	if (!test_bit(i, msg->sg.copy) && bytes_sg_total <= len)
2620 		goto out;
2621 
2622 	/* At this point we need to linearize multiple scatterlist
2623 	 * elements or a single shared page. Either way we need to
2624 	 * copy into a linear buffer exclusively owned by BPF. Then
2625 	 * place the buffer in the scatterlist and fixup the original
2626 	 * entries by removing the entries now in the linear buffer
2627 	 * and shifting the remaining entries. For now we do not try
2628 	 * to copy partial entries to avoid complexity of running out
2629 	 * of sg_entry slots. The downside is reading a single byte
2630 	 * will copy the entire sg entry.
2631 	 */
2632 	do {
2633 		copy += sk_msg_elem(msg, i)->length;
2634 		sk_msg_iter_var_next(i);
2635 		if (bytes_sg_total <= copy)
2636 			break;
2637 	} while (i != msg->sg.end);
2638 	last_sge = i;
2639 
2640 	if (unlikely(bytes_sg_total > copy))
2641 		return -EINVAL;
2642 
2643 	page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2644 			   get_order(copy));
2645 	if (unlikely(!page))
2646 		return -ENOMEM;
2647 
2648 	raw = page_address(page);
2649 	i = first_sge;
2650 	do {
2651 		sge = sk_msg_elem(msg, i);
2652 		from = sg_virt(sge);
2653 		len = sge->length;
2654 		to = raw + poffset;
2655 
2656 		memcpy(to, from, len);
2657 		poffset += len;
2658 		sge->length = 0;
2659 		put_page(sg_page(sge));
2660 
2661 		sk_msg_iter_var_next(i);
2662 	} while (i != last_sge);
2663 
2664 	sg_set_page(&msg->sg.data[first_sge], page, copy, 0);
2665 
2666 	/* To repair sg ring we need to shift entries. If we only
2667 	 * had a single entry though we can just replace it and
2668 	 * be done. Otherwise walk the ring and shift the entries.
2669 	 */
2670 	WARN_ON_ONCE(last_sge == first_sge);
2671 	shift = last_sge > first_sge ?
2672 		last_sge - first_sge - 1 :
2673 		NR_MSG_FRAG_IDS - first_sge + last_sge - 1;
2674 	if (!shift)
2675 		goto out;
2676 
2677 	i = first_sge;
2678 	sk_msg_iter_var_next(i);
2679 	do {
2680 		u32 move_from;
2681 
2682 		if (i + shift >= NR_MSG_FRAG_IDS)
2683 			move_from = i + shift - NR_MSG_FRAG_IDS;
2684 		else
2685 			move_from = i + shift;
2686 		if (move_from == msg->sg.end)
2687 			break;
2688 
2689 		msg->sg.data[i] = msg->sg.data[move_from];
2690 		msg->sg.data[move_from].length = 0;
2691 		msg->sg.data[move_from].page_link = 0;
2692 		msg->sg.data[move_from].offset = 0;
2693 		sk_msg_iter_var_next(i);
2694 	} while (1);
2695 
2696 	msg->sg.end = msg->sg.end - shift > msg->sg.end ?
2697 		      msg->sg.end - shift + NR_MSG_FRAG_IDS :
2698 		      msg->sg.end - shift;
2699 out:
2700 	msg->data = sg_virt(&msg->sg.data[first_sge]) + start - offset;
2701 	msg->data_end = msg->data + bytes;
2702 	return 0;
2703 }
2704 
2705 static const struct bpf_func_proto bpf_msg_pull_data_proto = {
2706 	.func		= bpf_msg_pull_data,
2707 	.gpl_only	= false,
2708 	.ret_type	= RET_INTEGER,
2709 	.arg1_type	= ARG_PTR_TO_CTX,
2710 	.arg2_type	= ARG_ANYTHING,
2711 	.arg3_type	= ARG_ANYTHING,
2712 	.arg4_type	= ARG_ANYTHING,
2713 };
2714 
BPF_CALL_4(bpf_msg_push_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2715 BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start,
2716 	   u32, len, u64, flags)
2717 {
2718 	struct scatterlist sge, nsge, nnsge, rsge = {0}, *psge;
2719 	u32 new, i = 0, l = 0, space, copy = 0, offset = 0;
2720 	u8 *raw, *to, *from;
2721 	struct page *page;
2722 
2723 	if (unlikely(flags))
2724 		return -EINVAL;
2725 
2726 	if (unlikely(len == 0))
2727 		return 0;
2728 
2729 	/* First find the starting scatterlist element */
2730 	i = msg->sg.start;
2731 	do {
2732 		offset += l;
2733 		l = sk_msg_elem(msg, i)->length;
2734 
2735 		if (start < offset + l)
2736 			break;
2737 		sk_msg_iter_var_next(i);
2738 	} while (i != msg->sg.end);
2739 
2740 	if (start >= offset + l)
2741 		return -EINVAL;
2742 
2743 	space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2744 
2745 	/* If no space available will fallback to copy, we need at
2746 	 * least one scatterlist elem available to push data into
2747 	 * when start aligns to the beginning of an element or two
2748 	 * when it falls inside an element. We handle the start equals
2749 	 * offset case because its the common case for inserting a
2750 	 * header.
2751 	 */
2752 	if (!space || (space == 1 && start != offset))
2753 		copy = msg->sg.data[i].length;
2754 
2755 	page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2756 			   get_order(copy + len));
2757 	if (unlikely(!page))
2758 		return -ENOMEM;
2759 
2760 	if (copy) {
2761 		int front, back;
2762 
2763 		raw = page_address(page);
2764 
2765 		psge = sk_msg_elem(msg, i);
2766 		front = start - offset;
2767 		back = psge->length - front;
2768 		from = sg_virt(psge);
2769 
2770 		if (front)
2771 			memcpy(raw, from, front);
2772 
2773 		if (back) {
2774 			from += front;
2775 			to = raw + front + len;
2776 
2777 			memcpy(to, from, back);
2778 		}
2779 
2780 		put_page(sg_page(psge));
2781 	} else if (start - offset) {
2782 		psge = sk_msg_elem(msg, i);
2783 		rsge = sk_msg_elem_cpy(msg, i);
2784 
2785 		psge->length = start - offset;
2786 		rsge.length -= psge->length;
2787 		rsge.offset += start;
2788 
2789 		sk_msg_iter_var_next(i);
2790 		sg_unmark_end(psge);
2791 		sg_unmark_end(&rsge);
2792 		sk_msg_iter_next(msg, end);
2793 	}
2794 
2795 	/* Slot(s) to place newly allocated data */
2796 	new = i;
2797 
2798 	/* Shift one or two slots as needed */
2799 	if (!copy) {
2800 		sge = sk_msg_elem_cpy(msg, i);
2801 
2802 		sk_msg_iter_var_next(i);
2803 		sg_unmark_end(&sge);
2804 		sk_msg_iter_next(msg, end);
2805 
2806 		nsge = sk_msg_elem_cpy(msg, i);
2807 		if (rsge.length) {
2808 			sk_msg_iter_var_next(i);
2809 			nnsge = sk_msg_elem_cpy(msg, i);
2810 		}
2811 
2812 		while (i != msg->sg.end) {
2813 			msg->sg.data[i] = sge;
2814 			sge = nsge;
2815 			sk_msg_iter_var_next(i);
2816 			if (rsge.length) {
2817 				nsge = nnsge;
2818 				nnsge = sk_msg_elem_cpy(msg, i);
2819 			} else {
2820 				nsge = sk_msg_elem_cpy(msg, i);
2821 			}
2822 		}
2823 	}
2824 
2825 	/* Place newly allocated data buffer */
2826 	sk_mem_charge(msg->sk, len);
2827 	msg->sg.size += len;
2828 	__clear_bit(new, msg->sg.copy);
2829 	sg_set_page(&msg->sg.data[new], page, len + copy, 0);
2830 	if (rsge.length) {
2831 		get_page(sg_page(&rsge));
2832 		sk_msg_iter_var_next(new);
2833 		msg->sg.data[new] = rsge;
2834 	}
2835 
2836 	sk_msg_compute_data_pointers(msg);
2837 	return 0;
2838 }
2839 
2840 static const struct bpf_func_proto bpf_msg_push_data_proto = {
2841 	.func		= bpf_msg_push_data,
2842 	.gpl_only	= false,
2843 	.ret_type	= RET_INTEGER,
2844 	.arg1_type	= ARG_PTR_TO_CTX,
2845 	.arg2_type	= ARG_ANYTHING,
2846 	.arg3_type	= ARG_ANYTHING,
2847 	.arg4_type	= ARG_ANYTHING,
2848 };
2849 
sk_msg_shift_left(struct sk_msg * msg,int i)2850 static void sk_msg_shift_left(struct sk_msg *msg, int i)
2851 {
2852 	int prev;
2853 
2854 	do {
2855 		prev = i;
2856 		sk_msg_iter_var_next(i);
2857 		msg->sg.data[prev] = msg->sg.data[i];
2858 	} while (i != msg->sg.end);
2859 
2860 	sk_msg_iter_prev(msg, end);
2861 }
2862 
sk_msg_shift_right(struct sk_msg * msg,int i)2863 static void sk_msg_shift_right(struct sk_msg *msg, int i)
2864 {
2865 	struct scatterlist tmp, sge;
2866 
2867 	sk_msg_iter_next(msg, end);
2868 	sge = sk_msg_elem_cpy(msg, i);
2869 	sk_msg_iter_var_next(i);
2870 	tmp = sk_msg_elem_cpy(msg, i);
2871 
2872 	while (i != msg->sg.end) {
2873 		msg->sg.data[i] = sge;
2874 		sk_msg_iter_var_next(i);
2875 		sge = tmp;
2876 		tmp = sk_msg_elem_cpy(msg, i);
2877 	}
2878 }
2879 
BPF_CALL_4(bpf_msg_pop_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2880 BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start,
2881 	   u32, len, u64, flags)
2882 {
2883 	u32 i = 0, l = 0, space, offset = 0;
2884 	u64 last = start + len;
2885 	int pop;
2886 
2887 	if (unlikely(flags))
2888 		return -EINVAL;
2889 
2890 	/* First find the starting scatterlist element */
2891 	i = msg->sg.start;
2892 	do {
2893 		offset += l;
2894 		l = sk_msg_elem(msg, i)->length;
2895 
2896 		if (start < offset + l)
2897 			break;
2898 		sk_msg_iter_var_next(i);
2899 	} while (i != msg->sg.end);
2900 
2901 	/* Bounds checks: start and pop must be inside message */
2902 	if (start >= offset + l || last >= msg->sg.size)
2903 		return -EINVAL;
2904 
2905 	space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2906 
2907 	pop = len;
2908 	/* --------------| offset
2909 	 * -| start      |-------- len -------|
2910 	 *
2911 	 *  |----- a ----|-------- pop -------|----- b ----|
2912 	 *  |______________________________________________| length
2913 	 *
2914 	 *
2915 	 * a:   region at front of scatter element to save
2916 	 * b:   region at back of scatter element to save when length > A + pop
2917 	 * pop: region to pop from element, same as input 'pop' here will be
2918 	 *      decremented below per iteration.
2919 	 *
2920 	 * Two top-level cases to handle when start != offset, first B is non
2921 	 * zero and second B is zero corresponding to when a pop includes more
2922 	 * than one element.
2923 	 *
2924 	 * Then if B is non-zero AND there is no space allocate space and
2925 	 * compact A, B regions into page. If there is space shift ring to
2926 	 * the rigth free'ing the next element in ring to place B, leaving
2927 	 * A untouched except to reduce length.
2928 	 */
2929 	if (start != offset) {
2930 		struct scatterlist *nsge, *sge = sk_msg_elem(msg, i);
2931 		int a = start;
2932 		int b = sge->length - pop - a;
2933 
2934 		sk_msg_iter_var_next(i);
2935 
2936 		if (pop < sge->length - a) {
2937 			if (space) {
2938 				sge->length = a;
2939 				sk_msg_shift_right(msg, i);
2940 				nsge = sk_msg_elem(msg, i);
2941 				get_page(sg_page(sge));
2942 				sg_set_page(nsge,
2943 					    sg_page(sge),
2944 					    b, sge->offset + pop + a);
2945 			} else {
2946 				struct page *page, *orig;
2947 				u8 *to, *from;
2948 
2949 				page = alloc_pages(__GFP_NOWARN |
2950 						   __GFP_COMP   | GFP_ATOMIC,
2951 						   get_order(a + b));
2952 				if (unlikely(!page))
2953 					return -ENOMEM;
2954 
2955 				sge->length = a;
2956 				orig = sg_page(sge);
2957 				from = sg_virt(sge);
2958 				to = page_address(page);
2959 				memcpy(to, from, a);
2960 				memcpy(to + a, from + a + pop, b);
2961 				sg_set_page(sge, page, a + b, 0);
2962 				put_page(orig);
2963 			}
2964 			pop = 0;
2965 		} else if (pop >= sge->length - a) {
2966 			pop -= (sge->length - a);
2967 			sge->length = a;
2968 		}
2969 	}
2970 
2971 	/* From above the current layout _must_ be as follows,
2972 	 *
2973 	 * -| offset
2974 	 * -| start
2975 	 *
2976 	 *  |---- pop ---|---------------- b ------------|
2977 	 *  |____________________________________________| length
2978 	 *
2979 	 * Offset and start of the current msg elem are equal because in the
2980 	 * previous case we handled offset != start and either consumed the
2981 	 * entire element and advanced to the next element OR pop == 0.
2982 	 *
2983 	 * Two cases to handle here are first pop is less than the length
2984 	 * leaving some remainder b above. Simply adjust the element's layout
2985 	 * in this case. Or pop >= length of the element so that b = 0. In this
2986 	 * case advance to next element decrementing pop.
2987 	 */
2988 	while (pop) {
2989 		struct scatterlist *sge = sk_msg_elem(msg, i);
2990 
2991 		if (pop < sge->length) {
2992 			sge->length -= pop;
2993 			sge->offset += pop;
2994 			pop = 0;
2995 		} else {
2996 			pop -= sge->length;
2997 			sk_msg_shift_left(msg, i);
2998 		}
2999 		sk_msg_iter_var_next(i);
3000 	}
3001 
3002 	sk_mem_uncharge(msg->sk, len - pop);
3003 	msg->sg.size -= (len - pop);
3004 	sk_msg_compute_data_pointers(msg);
3005 	return 0;
3006 }
3007 
3008 static const struct bpf_func_proto bpf_msg_pop_data_proto = {
3009 	.func		= bpf_msg_pop_data,
3010 	.gpl_only	= false,
3011 	.ret_type	= RET_INTEGER,
3012 	.arg1_type	= ARG_PTR_TO_CTX,
3013 	.arg2_type	= ARG_ANYTHING,
3014 	.arg3_type	= ARG_ANYTHING,
3015 	.arg4_type	= ARG_ANYTHING,
3016 };
3017 
3018 #ifdef CONFIG_CGROUP_NET_CLASSID
BPF_CALL_0(bpf_get_cgroup_classid_curr)3019 BPF_CALL_0(bpf_get_cgroup_classid_curr)
3020 {
3021 	return __task_get_classid(current);
3022 }
3023 
3024 const struct bpf_func_proto bpf_get_cgroup_classid_curr_proto = {
3025 	.func		= bpf_get_cgroup_classid_curr,
3026 	.gpl_only	= false,
3027 	.ret_type	= RET_INTEGER,
3028 };
3029 
BPF_CALL_1(bpf_skb_cgroup_classid,const struct sk_buff *,skb)3030 BPF_CALL_1(bpf_skb_cgroup_classid, const struct sk_buff *, skb)
3031 {
3032 	struct sock *sk = skb_to_full_sk(skb);
3033 
3034 	if (!sk || !sk_fullsock(sk))
3035 		return 0;
3036 
3037 	return sock_cgroup_classid(&sk->sk_cgrp_data);
3038 }
3039 
3040 static const struct bpf_func_proto bpf_skb_cgroup_classid_proto = {
3041 	.func		= bpf_skb_cgroup_classid,
3042 	.gpl_only	= false,
3043 	.ret_type	= RET_INTEGER,
3044 	.arg1_type	= ARG_PTR_TO_CTX,
3045 };
3046 #endif
3047 
BPF_CALL_1(bpf_get_cgroup_classid,const struct sk_buff *,skb)3048 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
3049 {
3050 	return task_get_classid(skb);
3051 }
3052 
3053 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
3054 	.func           = bpf_get_cgroup_classid,
3055 	.gpl_only       = false,
3056 	.ret_type       = RET_INTEGER,
3057 	.arg1_type      = ARG_PTR_TO_CTX,
3058 };
3059 
BPF_CALL_1(bpf_get_route_realm,const struct sk_buff *,skb)3060 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
3061 {
3062 	return dst_tclassid(skb);
3063 }
3064 
3065 static const struct bpf_func_proto bpf_get_route_realm_proto = {
3066 	.func           = bpf_get_route_realm,
3067 	.gpl_only       = false,
3068 	.ret_type       = RET_INTEGER,
3069 	.arg1_type      = ARG_PTR_TO_CTX,
3070 };
3071 
BPF_CALL_1(bpf_get_hash_recalc,struct sk_buff *,skb)3072 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
3073 {
3074 	/* If skb_clear_hash() was called due to mangling, we can
3075 	 * trigger SW recalculation here. Later access to hash
3076 	 * can then use the inline skb->hash via context directly
3077 	 * instead of calling this helper again.
3078 	 */
3079 	return skb_get_hash(skb);
3080 }
3081 
3082 static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
3083 	.func		= bpf_get_hash_recalc,
3084 	.gpl_only	= false,
3085 	.ret_type	= RET_INTEGER,
3086 	.arg1_type	= ARG_PTR_TO_CTX,
3087 };
3088 
BPF_CALL_1(bpf_set_hash_invalid,struct sk_buff *,skb)3089 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
3090 {
3091 	/* After all direct packet write, this can be used once for
3092 	 * triggering a lazy recalc on next skb_get_hash() invocation.
3093 	 */
3094 	skb_clear_hash(skb);
3095 	return 0;
3096 }
3097 
3098 static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
3099 	.func		= bpf_set_hash_invalid,
3100 	.gpl_only	= false,
3101 	.ret_type	= RET_INTEGER,
3102 	.arg1_type	= ARG_PTR_TO_CTX,
3103 };
3104 
BPF_CALL_2(bpf_set_hash,struct sk_buff *,skb,u32,hash)3105 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
3106 {
3107 	/* Set user specified hash as L4(+), so that it gets returned
3108 	 * on skb_get_hash() call unless BPF prog later on triggers a
3109 	 * skb_clear_hash().
3110 	 */
3111 	__skb_set_sw_hash(skb, hash, true);
3112 	return 0;
3113 }
3114 
3115 static const struct bpf_func_proto bpf_set_hash_proto = {
3116 	.func		= bpf_set_hash,
3117 	.gpl_only	= false,
3118 	.ret_type	= RET_INTEGER,
3119 	.arg1_type	= ARG_PTR_TO_CTX,
3120 	.arg2_type	= ARG_ANYTHING,
3121 };
3122 
BPF_CALL_3(bpf_skb_vlan_push,struct sk_buff *,skb,__be16,vlan_proto,u16,vlan_tci)3123 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
3124 	   u16, vlan_tci)
3125 {
3126 	int ret;
3127 
3128 	if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
3129 		     vlan_proto != htons(ETH_P_8021AD)))
3130 		vlan_proto = htons(ETH_P_8021Q);
3131 
3132 	bpf_push_mac_rcsum(skb);
3133 	ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
3134 	bpf_pull_mac_rcsum(skb);
3135 
3136 	bpf_compute_data_pointers(skb);
3137 	return ret;
3138 }
3139 
3140 static const struct bpf_func_proto bpf_skb_vlan_push_proto = {
3141 	.func           = bpf_skb_vlan_push,
3142 	.gpl_only       = false,
3143 	.ret_type       = RET_INTEGER,
3144 	.arg1_type      = ARG_PTR_TO_CTX,
3145 	.arg2_type      = ARG_ANYTHING,
3146 	.arg3_type      = ARG_ANYTHING,
3147 };
3148 
BPF_CALL_1(bpf_skb_vlan_pop,struct sk_buff *,skb)3149 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
3150 {
3151 	int ret;
3152 
3153 	bpf_push_mac_rcsum(skb);
3154 	ret = skb_vlan_pop(skb);
3155 	bpf_pull_mac_rcsum(skb);
3156 
3157 	bpf_compute_data_pointers(skb);
3158 	return ret;
3159 }
3160 
3161 static const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
3162 	.func           = bpf_skb_vlan_pop,
3163 	.gpl_only       = false,
3164 	.ret_type       = RET_INTEGER,
3165 	.arg1_type      = ARG_PTR_TO_CTX,
3166 };
3167 
bpf_skb_generic_push(struct sk_buff * skb,u32 off,u32 len)3168 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
3169 {
3170 	/* Caller already did skb_cow() with len as headroom,
3171 	 * so no need to do it here.
3172 	 */
3173 	skb_push(skb, len);
3174 	memmove(skb->data, skb->data + len, off);
3175 	memset(skb->data + off, 0, len);
3176 
3177 	/* No skb_postpush_rcsum(skb, skb->data + off, len)
3178 	 * needed here as it does not change the skb->csum
3179 	 * result for checksum complete when summing over
3180 	 * zeroed blocks.
3181 	 */
3182 	return 0;
3183 }
3184 
bpf_skb_generic_pop(struct sk_buff * skb,u32 off,u32 len)3185 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
3186 {
3187 	void *old_data;
3188 
3189 	/* skb_ensure_writable() is not needed here, as we're
3190 	 * already working on an uncloned skb.
3191 	 */
3192 	if (unlikely(!pskb_may_pull(skb, off + len)))
3193 		return -ENOMEM;
3194 
3195 	old_data = skb->data;
3196 	__skb_pull(skb, len);
3197 	skb_postpull_rcsum(skb, old_data + off, len);
3198 	memmove(skb->data, old_data, off);
3199 
3200 	return 0;
3201 }
3202 
bpf_skb_net_hdr_push(struct sk_buff * skb,u32 off,u32 len)3203 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
3204 {
3205 	bool trans_same = skb->transport_header == skb->network_header;
3206 	int ret;
3207 
3208 	/* There's no need for __skb_push()/__skb_pull() pair to
3209 	 * get to the start of the mac header as we're guaranteed
3210 	 * to always start from here under eBPF.
3211 	 */
3212 	ret = bpf_skb_generic_push(skb, off, len);
3213 	if (likely(!ret)) {
3214 		skb->mac_header -= len;
3215 		skb->network_header -= len;
3216 		if (trans_same)
3217 			skb->transport_header = skb->network_header;
3218 	}
3219 
3220 	return ret;
3221 }
3222 
bpf_skb_net_hdr_pop(struct sk_buff * skb,u32 off,u32 len)3223 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
3224 {
3225 	bool trans_same = skb->transport_header == skb->network_header;
3226 	int ret;
3227 
3228 	/* Same here, __skb_push()/__skb_pull() pair not needed. */
3229 	ret = bpf_skb_generic_pop(skb, off, len);
3230 	if (likely(!ret)) {
3231 		skb->mac_header += len;
3232 		skb->network_header += len;
3233 		if (trans_same)
3234 			skb->transport_header = skb->network_header;
3235 	}
3236 
3237 	return ret;
3238 }
3239 
bpf_skb_proto_4_to_6(struct sk_buff * skb)3240 static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
3241 {
3242 	const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
3243 	u32 off = skb_mac_header_len(skb);
3244 	int ret;
3245 
3246 	ret = skb_cow(skb, len_diff);
3247 	if (unlikely(ret < 0))
3248 		return ret;
3249 
3250 	ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3251 	if (unlikely(ret < 0))
3252 		return ret;
3253 
3254 	if (skb_is_gso(skb)) {
3255 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3256 
3257 		/* SKB_GSO_TCPV4 needs to be changed into SKB_GSO_TCPV6. */
3258 		if (shinfo->gso_type & SKB_GSO_TCPV4) {
3259 			shinfo->gso_type &= ~SKB_GSO_TCPV4;
3260 			shinfo->gso_type |=  SKB_GSO_TCPV6;
3261 		}
3262 	}
3263 
3264 	skb->protocol = htons(ETH_P_IPV6);
3265 	skb_clear_hash(skb);
3266 
3267 	return 0;
3268 }
3269 
bpf_skb_proto_6_to_4(struct sk_buff * skb)3270 static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
3271 {
3272 	const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
3273 	u32 off = skb_mac_header_len(skb);
3274 	int ret;
3275 
3276 	ret = skb_unclone(skb, GFP_ATOMIC);
3277 	if (unlikely(ret < 0))
3278 		return ret;
3279 
3280 	ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3281 	if (unlikely(ret < 0))
3282 		return ret;
3283 
3284 	if (skb_is_gso(skb)) {
3285 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3286 
3287 		/* SKB_GSO_TCPV6 needs to be changed into SKB_GSO_TCPV4. */
3288 		if (shinfo->gso_type & SKB_GSO_TCPV6) {
3289 			shinfo->gso_type &= ~SKB_GSO_TCPV6;
3290 			shinfo->gso_type |=  SKB_GSO_TCPV4;
3291 		}
3292 	}
3293 
3294 	skb->protocol = htons(ETH_P_IP);
3295 	skb_clear_hash(skb);
3296 
3297 	return 0;
3298 }
3299 
bpf_skb_proto_xlat(struct sk_buff * skb,__be16 to_proto)3300 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
3301 {
3302 	__be16 from_proto = skb->protocol;
3303 
3304 	if (from_proto == htons(ETH_P_IP) &&
3305 	      to_proto == htons(ETH_P_IPV6))
3306 		return bpf_skb_proto_4_to_6(skb);
3307 
3308 	if (from_proto == htons(ETH_P_IPV6) &&
3309 	      to_proto == htons(ETH_P_IP))
3310 		return bpf_skb_proto_6_to_4(skb);
3311 
3312 	return -ENOTSUPP;
3313 }
3314 
BPF_CALL_3(bpf_skb_change_proto,struct sk_buff *,skb,__be16,proto,u64,flags)3315 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
3316 	   u64, flags)
3317 {
3318 	int ret;
3319 
3320 	if (unlikely(flags))
3321 		return -EINVAL;
3322 
3323 	/* General idea is that this helper does the basic groundwork
3324 	 * needed for changing the protocol, and eBPF program fills the
3325 	 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
3326 	 * and other helpers, rather than passing a raw buffer here.
3327 	 *
3328 	 * The rationale is to keep this minimal and without a need to
3329 	 * deal with raw packet data. F.e. even if we would pass buffers
3330 	 * here, the program still needs to call the bpf_lX_csum_replace()
3331 	 * helpers anyway. Plus, this way we keep also separation of
3332 	 * concerns, since f.e. bpf_skb_store_bytes() should only take
3333 	 * care of stores.
3334 	 *
3335 	 * Currently, additional options and extension header space are
3336 	 * not supported, but flags register is reserved so we can adapt
3337 	 * that. For offloads, we mark packet as dodgy, so that headers
3338 	 * need to be verified first.
3339 	 */
3340 	ret = bpf_skb_proto_xlat(skb, proto);
3341 	bpf_compute_data_pointers(skb);
3342 	return ret;
3343 }
3344 
3345 static const struct bpf_func_proto bpf_skb_change_proto_proto = {
3346 	.func		= bpf_skb_change_proto,
3347 	.gpl_only	= false,
3348 	.ret_type	= RET_INTEGER,
3349 	.arg1_type	= ARG_PTR_TO_CTX,
3350 	.arg2_type	= ARG_ANYTHING,
3351 	.arg3_type	= ARG_ANYTHING,
3352 };
3353 
BPF_CALL_2(bpf_skb_change_type,struct sk_buff *,skb,u32,pkt_type)3354 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
3355 {
3356 	/* We only allow a restricted subset to be changed for now. */
3357 	if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
3358 		     !skb_pkt_type_ok(pkt_type)))
3359 		return -EINVAL;
3360 
3361 	skb->pkt_type = pkt_type;
3362 	return 0;
3363 }
3364 
3365 static const struct bpf_func_proto bpf_skb_change_type_proto = {
3366 	.func		= bpf_skb_change_type,
3367 	.gpl_only	= false,
3368 	.ret_type	= RET_INTEGER,
3369 	.arg1_type	= ARG_PTR_TO_CTX,
3370 	.arg2_type	= ARG_ANYTHING,
3371 };
3372 
bpf_skb_net_base_len(const struct sk_buff * skb)3373 static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
3374 {
3375 	switch (skb->protocol) {
3376 	case htons(ETH_P_IP):
3377 		return sizeof(struct iphdr);
3378 	case htons(ETH_P_IPV6):
3379 		return sizeof(struct ipv6hdr);
3380 	default:
3381 		return ~0U;
3382 	}
3383 }
3384 
3385 #define BPF_F_ADJ_ROOM_ENCAP_L3_MASK	(BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 | \
3386 					 BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3387 
3388 #define BPF_F_ADJ_ROOM_MASK		(BPF_F_ADJ_ROOM_FIXED_GSO | \
3389 					 BPF_F_ADJ_ROOM_ENCAP_L3_MASK | \
3390 					 BPF_F_ADJ_ROOM_ENCAP_L4_GRE | \
3391 					 BPF_F_ADJ_ROOM_ENCAP_L4_UDP | \
3392 					 BPF_F_ADJ_ROOM_ENCAP_L2_ETH | \
3393 					 BPF_F_ADJ_ROOM_ENCAP_L2( \
3394 					  BPF_ADJ_ROOM_ENCAP_L2_MASK))
3395 
bpf_skb_net_grow(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3396 static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff,
3397 			    u64 flags)
3398 {
3399 	u8 inner_mac_len = flags >> BPF_ADJ_ROOM_ENCAP_L2_SHIFT;
3400 	bool encap = flags & BPF_F_ADJ_ROOM_ENCAP_L3_MASK;
3401 	u16 mac_len = 0, inner_net = 0, inner_trans = 0;
3402 	unsigned int gso_type = SKB_GSO_DODGY;
3403 	int ret;
3404 
3405 	if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3406 		/* udp gso_size delineates datagrams, only allow if fixed */
3407 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3408 		    !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3409 			return -ENOTSUPP;
3410 	}
3411 
3412 	ret = skb_cow_head(skb, len_diff);
3413 	if (unlikely(ret < 0))
3414 		return ret;
3415 
3416 	if (encap) {
3417 		if (skb->protocol != htons(ETH_P_IP) &&
3418 		    skb->protocol != htons(ETH_P_IPV6))
3419 			return -ENOTSUPP;
3420 
3421 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 &&
3422 		    flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3423 			return -EINVAL;
3424 
3425 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE &&
3426 		    flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3427 			return -EINVAL;
3428 
3429 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH &&
3430 		    inner_mac_len < ETH_HLEN)
3431 			return -EINVAL;
3432 
3433 		if (skb->encapsulation)
3434 			return -EALREADY;
3435 
3436 		mac_len = skb->network_header - skb->mac_header;
3437 		inner_net = skb->network_header;
3438 		if (inner_mac_len > len_diff)
3439 			return -EINVAL;
3440 		inner_trans = skb->transport_header;
3441 	}
3442 
3443 	ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3444 	if (unlikely(ret < 0))
3445 		return ret;
3446 
3447 	if (encap) {
3448 		skb->inner_mac_header = inner_net - inner_mac_len;
3449 		skb->inner_network_header = inner_net;
3450 		skb->inner_transport_header = inner_trans;
3451 
3452 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH)
3453 			skb_set_inner_protocol(skb, htons(ETH_P_TEB));
3454 		else
3455 			skb_set_inner_protocol(skb, skb->protocol);
3456 
3457 		skb->encapsulation = 1;
3458 		skb_set_network_header(skb, mac_len);
3459 
3460 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3461 			gso_type |= SKB_GSO_UDP_TUNNEL;
3462 		else if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE)
3463 			gso_type |= SKB_GSO_GRE;
3464 		else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3465 			gso_type |= SKB_GSO_IPXIP6;
3466 		else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3467 			gso_type |= SKB_GSO_IPXIP4;
3468 
3469 		if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE ||
3470 		    flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP) {
3471 			int nh_len = flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 ?
3472 					sizeof(struct ipv6hdr) :
3473 					sizeof(struct iphdr);
3474 
3475 			skb_set_transport_header(skb, mac_len + nh_len);
3476 		}
3477 
3478 		/* Match skb->protocol to new outer l3 protocol */
3479 		if (skb->protocol == htons(ETH_P_IP) &&
3480 		    flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3481 			skb->protocol = htons(ETH_P_IPV6);
3482 		else if (skb->protocol == htons(ETH_P_IPV6) &&
3483 			 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3484 			skb->protocol = htons(ETH_P_IP);
3485 	}
3486 
3487 	if (skb_is_gso(skb)) {
3488 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3489 
3490 		/* Due to header grow, MSS needs to be downgraded. */
3491 		if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3492 			skb_decrease_gso_size(shinfo, len_diff);
3493 
3494 		/* Header must be checked, and gso_segs recomputed. */
3495 		shinfo->gso_type |= gso_type;
3496 		shinfo->gso_segs = 0;
3497 	}
3498 
3499 	return 0;
3500 }
3501 
bpf_skb_net_shrink(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3502 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 off, u32 len_diff,
3503 			      u64 flags)
3504 {
3505 	int ret;
3506 
3507 	if (unlikely(flags & ~(BPF_F_ADJ_ROOM_FIXED_GSO |
3508 			       BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
3509 		return -EINVAL;
3510 
3511 	if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3512 		/* udp gso_size delineates datagrams, only allow if fixed */
3513 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3514 		    !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3515 			return -ENOTSUPP;
3516 	}
3517 
3518 	ret = skb_unclone(skb, GFP_ATOMIC);
3519 	if (unlikely(ret < 0))
3520 		return ret;
3521 
3522 	ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3523 	if (unlikely(ret < 0))
3524 		return ret;
3525 
3526 	if (skb_is_gso(skb)) {
3527 		struct skb_shared_info *shinfo = skb_shinfo(skb);
3528 
3529 		/* Due to header shrink, MSS can be upgraded. */
3530 		if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3531 			skb_increase_gso_size(shinfo, len_diff);
3532 
3533 		/* Header must be checked, and gso_segs recomputed. */
3534 		shinfo->gso_type |= SKB_GSO_DODGY;
3535 		shinfo->gso_segs = 0;
3536 	}
3537 
3538 	return 0;
3539 }
3540 
3541 #define BPF_SKB_MAX_LEN SKB_MAX_ALLOC
3542 
BPF_CALL_4(sk_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3543 BPF_CALL_4(sk_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3544 	   u32, mode, u64, flags)
3545 {
3546 	u32 len_diff_abs = abs(len_diff);
3547 	bool shrink = len_diff < 0;
3548 	int ret = 0;
3549 
3550 	if (unlikely(flags || mode))
3551 		return -EINVAL;
3552 	if (unlikely(len_diff_abs > 0xfffU))
3553 		return -EFAULT;
3554 
3555 	if (!shrink) {
3556 		ret = skb_cow(skb, len_diff);
3557 		if (unlikely(ret < 0))
3558 			return ret;
3559 		__skb_push(skb, len_diff_abs);
3560 		memset(skb->data, 0, len_diff_abs);
3561 	} else {
3562 		if (unlikely(!pskb_may_pull(skb, len_diff_abs)))
3563 			return -ENOMEM;
3564 		__skb_pull(skb, len_diff_abs);
3565 	}
3566 	if (tls_sw_has_ctx_rx(skb->sk)) {
3567 		struct strp_msg *rxm = strp_msg(skb);
3568 
3569 		rxm->full_len += len_diff;
3570 	}
3571 	return ret;
3572 }
3573 
3574 static const struct bpf_func_proto sk_skb_adjust_room_proto = {
3575 	.func		= sk_skb_adjust_room,
3576 	.gpl_only	= false,
3577 	.ret_type	= RET_INTEGER,
3578 	.arg1_type	= ARG_PTR_TO_CTX,
3579 	.arg2_type	= ARG_ANYTHING,
3580 	.arg3_type	= ARG_ANYTHING,
3581 	.arg4_type	= ARG_ANYTHING,
3582 };
3583 
BPF_CALL_4(bpf_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3584 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3585 	   u32, mode, u64, flags)
3586 {
3587 	u32 len_cur, len_diff_abs = abs(len_diff);
3588 	u32 len_min = bpf_skb_net_base_len(skb);
3589 	u32 len_max = BPF_SKB_MAX_LEN;
3590 	__be16 proto = skb->protocol;
3591 	bool shrink = len_diff < 0;
3592 	u32 off;
3593 	int ret;
3594 
3595 	if (unlikely(flags & ~(BPF_F_ADJ_ROOM_MASK |
3596 			       BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
3597 		return -EINVAL;
3598 	if (unlikely(len_diff_abs > 0xfffU))
3599 		return -EFAULT;
3600 	if (unlikely(proto != htons(ETH_P_IP) &&
3601 		     proto != htons(ETH_P_IPV6)))
3602 		return -ENOTSUPP;
3603 
3604 	off = skb_mac_header_len(skb);
3605 	switch (mode) {
3606 	case BPF_ADJ_ROOM_NET:
3607 		off += bpf_skb_net_base_len(skb);
3608 		break;
3609 	case BPF_ADJ_ROOM_MAC:
3610 		break;
3611 	default:
3612 		return -ENOTSUPP;
3613 	}
3614 
3615 	len_cur = skb->len - skb_network_offset(skb);
3616 	if ((shrink && (len_diff_abs >= len_cur ||
3617 			len_cur - len_diff_abs < len_min)) ||
3618 	    (!shrink && (skb->len + len_diff_abs > len_max &&
3619 			 !skb_is_gso(skb))))
3620 		return -ENOTSUPP;
3621 
3622 	ret = shrink ? bpf_skb_net_shrink(skb, off, len_diff_abs, flags) :
3623 		       bpf_skb_net_grow(skb, off, len_diff_abs, flags);
3624 	if (!ret && !(flags & BPF_F_ADJ_ROOM_NO_CSUM_RESET))
3625 		__skb_reset_checksum_unnecessary(skb);
3626 
3627 	bpf_compute_data_pointers(skb);
3628 	return ret;
3629 }
3630 
3631 static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
3632 	.func		= bpf_skb_adjust_room,
3633 	.gpl_only	= false,
3634 	.ret_type	= RET_INTEGER,
3635 	.arg1_type	= ARG_PTR_TO_CTX,
3636 	.arg2_type	= ARG_ANYTHING,
3637 	.arg3_type	= ARG_ANYTHING,
3638 	.arg4_type	= ARG_ANYTHING,
3639 };
3640 
__bpf_skb_min_len(const struct sk_buff * skb)3641 static u32 __bpf_skb_min_len(const struct sk_buff *skb)
3642 {
3643 	u32 min_len = skb_network_offset(skb);
3644 
3645 	if (skb_transport_header_was_set(skb))
3646 		min_len = skb_transport_offset(skb);
3647 	if (skb->ip_summed == CHECKSUM_PARTIAL)
3648 		min_len = skb_checksum_start_offset(skb) +
3649 			  skb->csum_offset + sizeof(__sum16);
3650 	return min_len;
3651 }
3652 
bpf_skb_grow_rcsum(struct sk_buff * skb,unsigned int new_len)3653 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
3654 {
3655 	unsigned int old_len = skb->len;
3656 	int ret;
3657 
3658 	ret = __skb_grow_rcsum(skb, new_len);
3659 	if (!ret)
3660 		memset(skb->data + old_len, 0, new_len - old_len);
3661 	return ret;
3662 }
3663 
bpf_skb_trim_rcsum(struct sk_buff * skb,unsigned int new_len)3664 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
3665 {
3666 	return __skb_trim_rcsum(skb, new_len);
3667 }
3668 
__bpf_skb_change_tail(struct sk_buff * skb,u32 new_len,u64 flags)3669 static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len,
3670 					u64 flags)
3671 {
3672 	u32 max_len = BPF_SKB_MAX_LEN;
3673 	u32 min_len = __bpf_skb_min_len(skb);
3674 	int ret;
3675 
3676 	if (unlikely(flags || new_len > max_len || new_len < min_len))
3677 		return -EINVAL;
3678 	if (skb->encapsulation)
3679 		return -ENOTSUPP;
3680 
3681 	/* The basic idea of this helper is that it's performing the
3682 	 * needed work to either grow or trim an skb, and eBPF program
3683 	 * rewrites the rest via helpers like bpf_skb_store_bytes(),
3684 	 * bpf_lX_csum_replace() and others rather than passing a raw
3685 	 * buffer here. This one is a slow path helper and intended
3686 	 * for replies with control messages.
3687 	 *
3688 	 * Like in bpf_skb_change_proto(), we want to keep this rather
3689 	 * minimal and without protocol specifics so that we are able
3690 	 * to separate concerns as in bpf_skb_store_bytes() should only
3691 	 * be the one responsible for writing buffers.
3692 	 *
3693 	 * It's really expected to be a slow path operation here for
3694 	 * control message replies, so we're implicitly linearizing,
3695 	 * uncloning and drop offloads from the skb by this.
3696 	 */
3697 	ret = __bpf_try_make_writable(skb, skb->len);
3698 	if (!ret) {
3699 		if (new_len > skb->len)
3700 			ret = bpf_skb_grow_rcsum(skb, new_len);
3701 		else if (new_len < skb->len)
3702 			ret = bpf_skb_trim_rcsum(skb, new_len);
3703 		if (!ret && skb_is_gso(skb))
3704 			skb_gso_reset(skb);
3705 	}
3706 	return ret;
3707 }
3708 
BPF_CALL_3(bpf_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3709 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3710 	   u64, flags)
3711 {
3712 	int ret = __bpf_skb_change_tail(skb, new_len, flags);
3713 
3714 	bpf_compute_data_pointers(skb);
3715 	return ret;
3716 }
3717 
3718 static const struct bpf_func_proto bpf_skb_change_tail_proto = {
3719 	.func		= bpf_skb_change_tail,
3720 	.gpl_only	= false,
3721 	.ret_type	= RET_INTEGER,
3722 	.arg1_type	= ARG_PTR_TO_CTX,
3723 	.arg2_type	= ARG_ANYTHING,
3724 	.arg3_type	= ARG_ANYTHING,
3725 };
3726 
BPF_CALL_3(sk_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3727 BPF_CALL_3(sk_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3728 	   u64, flags)
3729 {
3730 	return __bpf_skb_change_tail(skb, new_len, flags);
3731 }
3732 
3733 static const struct bpf_func_proto sk_skb_change_tail_proto = {
3734 	.func		= sk_skb_change_tail,
3735 	.gpl_only	= false,
3736 	.ret_type	= RET_INTEGER,
3737 	.arg1_type	= ARG_PTR_TO_CTX,
3738 	.arg2_type	= ARG_ANYTHING,
3739 	.arg3_type	= ARG_ANYTHING,
3740 };
3741 
__bpf_skb_change_head(struct sk_buff * skb,u32 head_room,u64 flags)3742 static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room,
3743 					u64 flags)
3744 {
3745 	u32 max_len = BPF_SKB_MAX_LEN;
3746 	u32 new_len = skb->len + head_room;
3747 	int ret;
3748 
3749 	if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
3750 		     new_len < skb->len))
3751 		return -EINVAL;
3752 
3753 	ret = skb_cow(skb, head_room);
3754 	if (likely(!ret)) {
3755 		/* Idea for this helper is that we currently only
3756 		 * allow to expand on mac header. This means that
3757 		 * skb->protocol network header, etc, stay as is.
3758 		 * Compared to bpf_skb_change_tail(), we're more
3759 		 * flexible due to not needing to linearize or
3760 		 * reset GSO. Intention for this helper is to be
3761 		 * used by an L3 skb that needs to push mac header
3762 		 * for redirection into L2 device.
3763 		 */
3764 		__skb_push(skb, head_room);
3765 		memset(skb->data, 0, head_room);
3766 		skb_reset_mac_header(skb);
3767 		skb_reset_mac_len(skb);
3768 	}
3769 
3770 	return ret;
3771 }
3772 
BPF_CALL_3(bpf_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3773 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
3774 	   u64, flags)
3775 {
3776 	int ret = __bpf_skb_change_head(skb, head_room, flags);
3777 
3778 	bpf_compute_data_pointers(skb);
3779 	return ret;
3780 }
3781 
3782 static const struct bpf_func_proto bpf_skb_change_head_proto = {
3783 	.func		= bpf_skb_change_head,
3784 	.gpl_only	= false,
3785 	.ret_type	= RET_INTEGER,
3786 	.arg1_type	= ARG_PTR_TO_CTX,
3787 	.arg2_type	= ARG_ANYTHING,
3788 	.arg3_type	= ARG_ANYTHING,
3789 };
3790 
BPF_CALL_3(sk_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3791 BPF_CALL_3(sk_skb_change_head, struct sk_buff *, skb, u32, head_room,
3792 	   u64, flags)
3793 {
3794 	return __bpf_skb_change_head(skb, head_room, flags);
3795 }
3796 
3797 static const struct bpf_func_proto sk_skb_change_head_proto = {
3798 	.func		= sk_skb_change_head,
3799 	.gpl_only	= false,
3800 	.ret_type	= RET_INTEGER,
3801 	.arg1_type	= ARG_PTR_TO_CTX,
3802 	.arg2_type	= ARG_ANYTHING,
3803 	.arg3_type	= ARG_ANYTHING,
3804 };
3805 
BPF_CALL_1(bpf_xdp_get_buff_len,struct xdp_buff *,xdp)3806 BPF_CALL_1(bpf_xdp_get_buff_len, struct  xdp_buff*, xdp)
3807 {
3808 	return xdp_get_buff_len(xdp);
3809 }
3810 
3811 static const struct bpf_func_proto bpf_xdp_get_buff_len_proto = {
3812 	.func		= bpf_xdp_get_buff_len,
3813 	.gpl_only	= false,
3814 	.ret_type	= RET_INTEGER,
3815 	.arg1_type	= ARG_PTR_TO_CTX,
3816 };
3817 
3818 BTF_ID_LIST_SINGLE(bpf_xdp_get_buff_len_bpf_ids, struct, xdp_buff)
3819 
3820 const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto = {
3821 	.func		= bpf_xdp_get_buff_len,
3822 	.gpl_only	= false,
3823 	.arg1_type	= ARG_PTR_TO_BTF_ID,
3824 	.arg1_btf_id	= &bpf_xdp_get_buff_len_bpf_ids[0],
3825 };
3826 
xdp_get_metalen(const struct xdp_buff * xdp)3827 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
3828 {
3829 	return xdp_data_meta_unsupported(xdp) ? 0 :
3830 	       xdp->data - xdp->data_meta;
3831 }
3832 
BPF_CALL_2(bpf_xdp_adjust_head,struct xdp_buff *,xdp,int,offset)3833 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
3834 {
3835 	void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
3836 	unsigned long metalen = xdp_get_metalen(xdp);
3837 	void *data_start = xdp_frame_end + metalen;
3838 	void *data = xdp->data + offset;
3839 
3840 	if (unlikely(data < data_start ||
3841 		     data > xdp->data_end - ETH_HLEN))
3842 		return -EINVAL;
3843 
3844 	if (metalen)
3845 		memmove(xdp->data_meta + offset,
3846 			xdp->data_meta, metalen);
3847 	xdp->data_meta += offset;
3848 	xdp->data = data;
3849 
3850 	return 0;
3851 }
3852 
3853 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
3854 	.func		= bpf_xdp_adjust_head,
3855 	.gpl_only	= false,
3856 	.ret_type	= RET_INTEGER,
3857 	.arg1_type	= ARG_PTR_TO_CTX,
3858 	.arg2_type	= ARG_ANYTHING,
3859 };
3860 
bpf_xdp_copy_buf(struct xdp_buff * xdp,unsigned long off,void * buf,unsigned long len,bool flush)3861 static void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off,
3862 			     void *buf, unsigned long len, bool flush)
3863 {
3864 	unsigned long ptr_len, ptr_off = 0;
3865 	skb_frag_t *next_frag, *end_frag;
3866 	struct skb_shared_info *sinfo;
3867 	void *src, *dst;
3868 	u8 *ptr_buf;
3869 
3870 	if (likely(xdp->data_end - xdp->data >= off + len)) {
3871 		src = flush ? buf : xdp->data + off;
3872 		dst = flush ? xdp->data + off : buf;
3873 		memcpy(dst, src, len);
3874 		return;
3875 	}
3876 
3877 	sinfo = xdp_get_shared_info_from_buff(xdp);
3878 	end_frag = &sinfo->frags[sinfo->nr_frags];
3879 	next_frag = &sinfo->frags[0];
3880 
3881 	ptr_len = xdp->data_end - xdp->data;
3882 	ptr_buf = xdp->data;
3883 
3884 	while (true) {
3885 		if (off < ptr_off + ptr_len) {
3886 			unsigned long copy_off = off - ptr_off;
3887 			unsigned long copy_len = min(len, ptr_len - copy_off);
3888 
3889 			src = flush ? buf : ptr_buf + copy_off;
3890 			dst = flush ? ptr_buf + copy_off : buf;
3891 			memcpy(dst, src, copy_len);
3892 
3893 			off += copy_len;
3894 			len -= copy_len;
3895 			buf += copy_len;
3896 		}
3897 
3898 		if (!len || next_frag == end_frag)
3899 			break;
3900 
3901 		ptr_off += ptr_len;
3902 		ptr_buf = skb_frag_address(next_frag);
3903 		ptr_len = skb_frag_size(next_frag);
3904 		next_frag++;
3905 	}
3906 }
3907 
bpf_xdp_pointer(struct xdp_buff * xdp,u32 offset,u32 len)3908 static void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len)
3909 {
3910 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
3911 	u32 size = xdp->data_end - xdp->data;
3912 	void *addr = xdp->data;
3913 	int i;
3914 
3915 	if (unlikely(offset > 0xffff || len > 0xffff))
3916 		return ERR_PTR(-EFAULT);
3917 
3918 	if (offset + len > xdp_get_buff_len(xdp))
3919 		return ERR_PTR(-EINVAL);
3920 
3921 	if (offset < size) /* linear area */
3922 		goto out;
3923 
3924 	offset -= size;
3925 	for (i = 0; i < sinfo->nr_frags; i++) { /* paged area */
3926 		u32 frag_size = skb_frag_size(&sinfo->frags[i]);
3927 
3928 		if  (offset < frag_size) {
3929 			addr = skb_frag_address(&sinfo->frags[i]);
3930 			size = frag_size;
3931 			break;
3932 		}
3933 		offset -= frag_size;
3934 	}
3935 out:
3936 	return offset + len <= size ? addr + offset : NULL;
3937 }
3938 
BPF_CALL_4(bpf_xdp_load_bytes,struct xdp_buff *,xdp,u32,offset,void *,buf,u32,len)3939 BPF_CALL_4(bpf_xdp_load_bytes, struct xdp_buff *, xdp, u32, offset,
3940 	   void *, buf, u32, len)
3941 {
3942 	void *ptr;
3943 
3944 	ptr = bpf_xdp_pointer(xdp, offset, len);
3945 	if (IS_ERR(ptr))
3946 		return PTR_ERR(ptr);
3947 
3948 	if (!ptr)
3949 		bpf_xdp_copy_buf(xdp, offset, buf, len, false);
3950 	else
3951 		memcpy(buf, ptr, len);
3952 
3953 	return 0;
3954 }
3955 
3956 static const struct bpf_func_proto bpf_xdp_load_bytes_proto = {
3957 	.func		= bpf_xdp_load_bytes,
3958 	.gpl_only	= false,
3959 	.ret_type	= RET_INTEGER,
3960 	.arg1_type	= ARG_PTR_TO_CTX,
3961 	.arg2_type	= ARG_ANYTHING,
3962 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
3963 	.arg4_type	= ARG_CONST_SIZE,
3964 };
3965 
BPF_CALL_4(bpf_xdp_store_bytes,struct xdp_buff *,xdp,u32,offset,void *,buf,u32,len)3966 BPF_CALL_4(bpf_xdp_store_bytes, struct xdp_buff *, xdp, u32, offset,
3967 	   void *, buf, u32, len)
3968 {
3969 	void *ptr;
3970 
3971 	ptr = bpf_xdp_pointer(xdp, offset, len);
3972 	if (IS_ERR(ptr))
3973 		return PTR_ERR(ptr);
3974 
3975 	if (!ptr)
3976 		bpf_xdp_copy_buf(xdp, offset, buf, len, true);
3977 	else
3978 		memcpy(ptr, buf, len);
3979 
3980 	return 0;
3981 }
3982 
3983 static const struct bpf_func_proto bpf_xdp_store_bytes_proto = {
3984 	.func		= bpf_xdp_store_bytes,
3985 	.gpl_only	= false,
3986 	.ret_type	= RET_INTEGER,
3987 	.arg1_type	= ARG_PTR_TO_CTX,
3988 	.arg2_type	= ARG_ANYTHING,
3989 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
3990 	.arg4_type	= ARG_CONST_SIZE,
3991 };
3992 
bpf_xdp_frags_increase_tail(struct xdp_buff * xdp,int offset)3993 static int bpf_xdp_frags_increase_tail(struct xdp_buff *xdp, int offset)
3994 {
3995 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
3996 	skb_frag_t *frag = &sinfo->frags[sinfo->nr_frags - 1];
3997 	struct xdp_rxq_info *rxq = xdp->rxq;
3998 	unsigned int tailroom;
3999 
4000 	if (!rxq->frag_size || rxq->frag_size > xdp->frame_sz)
4001 		return -EOPNOTSUPP;
4002 
4003 	tailroom = rxq->frag_size - skb_frag_size(frag) - skb_frag_off(frag);
4004 	if (unlikely(offset > tailroom))
4005 		return -EINVAL;
4006 
4007 	memset(skb_frag_address(frag) + skb_frag_size(frag), 0, offset);
4008 	skb_frag_size_add(frag, offset);
4009 	sinfo->xdp_frags_size += offset;
4010 
4011 	return 0;
4012 }
4013 
bpf_xdp_frags_shrink_tail(struct xdp_buff * xdp,int offset)4014 static int bpf_xdp_frags_shrink_tail(struct xdp_buff *xdp, int offset)
4015 {
4016 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
4017 	int i, n_frags_free = 0, len_free = 0;
4018 
4019 	if (unlikely(offset > (int)xdp_get_buff_len(xdp) - ETH_HLEN))
4020 		return -EINVAL;
4021 
4022 	for (i = sinfo->nr_frags - 1; i >= 0 && offset > 0; i--) {
4023 		skb_frag_t *frag = &sinfo->frags[i];
4024 		int shrink = min_t(int, offset, skb_frag_size(frag));
4025 
4026 		len_free += shrink;
4027 		offset -= shrink;
4028 
4029 		if (skb_frag_size(frag) == shrink) {
4030 			struct page *page = skb_frag_page(frag);
4031 
4032 			__xdp_return(page_address(page), &xdp->rxq->mem,
4033 				     false, NULL);
4034 			n_frags_free++;
4035 		} else {
4036 			skb_frag_size_sub(frag, shrink);
4037 			break;
4038 		}
4039 	}
4040 	sinfo->nr_frags -= n_frags_free;
4041 	sinfo->xdp_frags_size -= len_free;
4042 
4043 	if (unlikely(!sinfo->nr_frags)) {
4044 		xdp_buff_clear_frags_flag(xdp);
4045 		xdp->data_end -= offset;
4046 	}
4047 
4048 	return 0;
4049 }
4050 
BPF_CALL_2(bpf_xdp_adjust_tail,struct xdp_buff *,xdp,int,offset)4051 BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset)
4052 {
4053 	void *data_hard_end = xdp_data_hard_end(xdp); /* use xdp->frame_sz */
4054 	void *data_end = xdp->data_end + offset;
4055 
4056 	if (unlikely(xdp_buff_has_frags(xdp))) { /* non-linear xdp buff */
4057 		if (offset < 0)
4058 			return bpf_xdp_frags_shrink_tail(xdp, -offset);
4059 
4060 		return bpf_xdp_frags_increase_tail(xdp, offset);
4061 	}
4062 
4063 	/* Notice that xdp_data_hard_end have reserved some tailroom */
4064 	if (unlikely(data_end > data_hard_end))
4065 		return -EINVAL;
4066 
4067 	/* ALL drivers MUST init xdp->frame_sz, chicken check below */
4068 	if (unlikely(xdp->frame_sz > PAGE_SIZE)) {
4069 		WARN_ONCE(1, "Too BIG xdp->frame_sz = %d\n", xdp->frame_sz);
4070 		return -EINVAL;
4071 	}
4072 
4073 	if (unlikely(data_end < xdp->data + ETH_HLEN))
4074 		return -EINVAL;
4075 
4076 	/* Clear memory area on grow, can contain uninit kernel memory */
4077 	if (offset > 0)
4078 		memset(xdp->data_end, 0, offset);
4079 
4080 	xdp->data_end = data_end;
4081 
4082 	return 0;
4083 }
4084 
4085 static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = {
4086 	.func		= bpf_xdp_adjust_tail,
4087 	.gpl_only	= false,
4088 	.ret_type	= RET_INTEGER,
4089 	.arg1_type	= ARG_PTR_TO_CTX,
4090 	.arg2_type	= ARG_ANYTHING,
4091 };
4092 
BPF_CALL_2(bpf_xdp_adjust_meta,struct xdp_buff *,xdp,int,offset)4093 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
4094 {
4095 	void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
4096 	void *meta = xdp->data_meta + offset;
4097 	unsigned long metalen = xdp->data - meta;
4098 
4099 	if (xdp_data_meta_unsupported(xdp))
4100 		return -ENOTSUPP;
4101 	if (unlikely(meta < xdp_frame_end ||
4102 		     meta > xdp->data))
4103 		return -EINVAL;
4104 	if (unlikely(xdp_metalen_invalid(metalen)))
4105 		return -EACCES;
4106 
4107 	xdp->data_meta = meta;
4108 
4109 	return 0;
4110 }
4111 
4112 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
4113 	.func		= bpf_xdp_adjust_meta,
4114 	.gpl_only	= false,
4115 	.ret_type	= RET_INTEGER,
4116 	.arg1_type	= ARG_PTR_TO_CTX,
4117 	.arg2_type	= ARG_ANYTHING,
4118 };
4119 
4120 /* XDP_REDIRECT works by a three-step process, implemented in the functions
4121  * below:
4122  *
4123  * 1. The bpf_redirect() and bpf_redirect_map() helpers will lookup the target
4124  *    of the redirect and store it (along with some other metadata) in a per-CPU
4125  *    struct bpf_redirect_info.
4126  *
4127  * 2. When the program returns the XDP_REDIRECT return code, the driver will
4128  *    call xdp_do_redirect() which will use the information in struct
4129  *    bpf_redirect_info to actually enqueue the frame into a map type-specific
4130  *    bulk queue structure.
4131  *
4132  * 3. Before exiting its NAPI poll loop, the driver will call xdp_do_flush(),
4133  *    which will flush all the different bulk queues, thus completing the
4134  *    redirect.
4135  *
4136  * Pointers to the map entries will be kept around for this whole sequence of
4137  * steps, protected by RCU. However, there is no top-level rcu_read_lock() in
4138  * the core code; instead, the RCU protection relies on everything happening
4139  * inside a single NAPI poll sequence, which means it's between a pair of calls
4140  * to local_bh_disable()/local_bh_enable().
4141  *
4142  * The map entries are marked as __rcu and the map code makes sure to
4143  * dereference those pointers with rcu_dereference_check() in a way that works
4144  * for both sections that to hold an rcu_read_lock() and sections that are
4145  * called from NAPI without a separate rcu_read_lock(). The code below does not
4146  * use RCU annotations, but relies on those in the map code.
4147  */
xdp_do_flush(void)4148 void xdp_do_flush(void)
4149 {
4150 	__dev_flush();
4151 	__cpu_map_flush();
4152 	__xsk_map_flush();
4153 }
4154 EXPORT_SYMBOL_GPL(xdp_do_flush);
4155 
bpf_clear_redirect_map(struct bpf_map * map)4156 void bpf_clear_redirect_map(struct bpf_map *map)
4157 {
4158 	struct bpf_redirect_info *ri;
4159 	int cpu;
4160 
4161 	for_each_possible_cpu(cpu) {
4162 		ri = per_cpu_ptr(&bpf_redirect_info, cpu);
4163 		/* Avoid polluting remote cacheline due to writes if
4164 		 * not needed. Once we pass this test, we need the
4165 		 * cmpxchg() to make sure it hasn't been changed in
4166 		 * the meantime by remote CPU.
4167 		 */
4168 		if (unlikely(READ_ONCE(ri->map) == map))
4169 			cmpxchg(&ri->map, map, NULL);
4170 	}
4171 }
4172 
4173 DEFINE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key);
4174 EXPORT_SYMBOL_GPL(bpf_master_redirect_enabled_key);
4175 
xdp_master_redirect(struct xdp_buff * xdp)4176 u32 xdp_master_redirect(struct xdp_buff *xdp)
4177 {
4178 	struct net_device *master, *slave;
4179 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4180 
4181 	master = netdev_master_upper_dev_get_rcu(xdp->rxq->dev);
4182 	slave = master->netdev_ops->ndo_xdp_get_xmit_slave(master, xdp);
4183 	if (slave && slave != xdp->rxq->dev) {
4184 		/* The target device is different from the receiving device, so
4185 		 * redirect it to the new device.
4186 		 * Using XDP_REDIRECT gets the correct behaviour from XDP enabled
4187 		 * drivers to unmap the packet from their rx ring.
4188 		 */
4189 		ri->tgt_index = slave->ifindex;
4190 		ri->map_id = INT_MAX;
4191 		ri->map_type = BPF_MAP_TYPE_UNSPEC;
4192 		return XDP_REDIRECT;
4193 	}
4194 	return XDP_TX;
4195 }
4196 EXPORT_SYMBOL_GPL(xdp_master_redirect);
4197 
__xdp_do_redirect_xsk(struct bpf_redirect_info * ri,struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4198 static inline int __xdp_do_redirect_xsk(struct bpf_redirect_info *ri,
4199 					struct net_device *dev,
4200 					struct xdp_buff *xdp,
4201 					struct bpf_prog *xdp_prog)
4202 {
4203 	enum bpf_map_type map_type = ri->map_type;
4204 	void *fwd = ri->tgt_value;
4205 	u32 map_id = ri->map_id;
4206 	int err;
4207 
4208 	ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4209 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4210 
4211 	err = __xsk_map_redirect(fwd, xdp);
4212 	if (unlikely(err))
4213 		goto err;
4214 
4215 	_trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4216 	return 0;
4217 err:
4218 	_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4219 	return err;
4220 }
4221 
__xdp_do_redirect_frame(struct bpf_redirect_info * ri,struct net_device * dev,struct xdp_frame * xdpf,struct bpf_prog * xdp_prog)4222 static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri,
4223 						   struct net_device *dev,
4224 						   struct xdp_frame *xdpf,
4225 						   struct bpf_prog *xdp_prog)
4226 {
4227 	enum bpf_map_type map_type = ri->map_type;
4228 	void *fwd = ri->tgt_value;
4229 	u32 map_id = ri->map_id;
4230 	struct bpf_map *map;
4231 	int err;
4232 
4233 	ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4234 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4235 
4236 	if (unlikely(!xdpf)) {
4237 		err = -EOVERFLOW;
4238 		goto err;
4239 	}
4240 
4241 	switch (map_type) {
4242 	case BPF_MAP_TYPE_DEVMAP:
4243 		fallthrough;
4244 	case BPF_MAP_TYPE_DEVMAP_HASH:
4245 		map = READ_ONCE(ri->map);
4246 		if (unlikely(map)) {
4247 			WRITE_ONCE(ri->map, NULL);
4248 			err = dev_map_enqueue_multi(xdpf, dev, map,
4249 						    ri->flags & BPF_F_EXCLUDE_INGRESS);
4250 		} else {
4251 			err = dev_map_enqueue(fwd, xdpf, dev);
4252 		}
4253 		break;
4254 	case BPF_MAP_TYPE_CPUMAP:
4255 		err = cpu_map_enqueue(fwd, xdpf, dev);
4256 		break;
4257 	case BPF_MAP_TYPE_UNSPEC:
4258 		if (map_id == INT_MAX) {
4259 			fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
4260 			if (unlikely(!fwd)) {
4261 				err = -EINVAL;
4262 				break;
4263 			}
4264 			err = dev_xdp_enqueue(fwd, xdpf, dev);
4265 			break;
4266 		}
4267 		fallthrough;
4268 	default:
4269 		err = -EBADRQC;
4270 	}
4271 
4272 	if (unlikely(err))
4273 		goto err;
4274 
4275 	_trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4276 	return 0;
4277 err:
4278 	_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4279 	return err;
4280 }
4281 
xdp_do_redirect(struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4282 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
4283 		    struct bpf_prog *xdp_prog)
4284 {
4285 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4286 	enum bpf_map_type map_type = ri->map_type;
4287 
4288 	/* XDP_REDIRECT is not fully supported yet for xdp frags since
4289 	 * not all XDP capable drivers can map non-linear xdp_frame in
4290 	 * ndo_xdp_xmit.
4291 	 */
4292 	if (unlikely(xdp_buff_has_frags(xdp) &&
4293 		     map_type != BPF_MAP_TYPE_CPUMAP))
4294 		return -EOPNOTSUPP;
4295 
4296 	if (map_type == BPF_MAP_TYPE_XSKMAP)
4297 		return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog);
4298 
4299 	return __xdp_do_redirect_frame(ri, dev, xdp_convert_buff_to_frame(xdp),
4300 				       xdp_prog);
4301 }
4302 EXPORT_SYMBOL_GPL(xdp_do_redirect);
4303 
xdp_do_redirect_frame(struct net_device * dev,struct xdp_buff * xdp,struct xdp_frame * xdpf,struct bpf_prog * xdp_prog)4304 int xdp_do_redirect_frame(struct net_device *dev, struct xdp_buff *xdp,
4305 			  struct xdp_frame *xdpf, struct bpf_prog *xdp_prog)
4306 {
4307 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4308 	enum bpf_map_type map_type = ri->map_type;
4309 
4310 	if (map_type == BPF_MAP_TYPE_XSKMAP)
4311 		return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog);
4312 
4313 	return __xdp_do_redirect_frame(ri, dev, xdpf, xdp_prog);
4314 }
4315 EXPORT_SYMBOL_GPL(xdp_do_redirect_frame);
4316 
xdp_do_generic_redirect_map(struct net_device * dev,struct sk_buff * skb,struct xdp_buff * xdp,struct bpf_prog * xdp_prog,void * fwd,enum bpf_map_type map_type,u32 map_id)4317 static int xdp_do_generic_redirect_map(struct net_device *dev,
4318 				       struct sk_buff *skb,
4319 				       struct xdp_buff *xdp,
4320 				       struct bpf_prog *xdp_prog,
4321 				       void *fwd,
4322 				       enum bpf_map_type map_type, u32 map_id)
4323 {
4324 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4325 	struct bpf_map *map;
4326 	int err;
4327 
4328 	switch (map_type) {
4329 	case BPF_MAP_TYPE_DEVMAP:
4330 		fallthrough;
4331 	case BPF_MAP_TYPE_DEVMAP_HASH:
4332 		map = READ_ONCE(ri->map);
4333 		if (unlikely(map)) {
4334 			WRITE_ONCE(ri->map, NULL);
4335 			err = dev_map_redirect_multi(dev, skb, xdp_prog, map,
4336 						     ri->flags & BPF_F_EXCLUDE_INGRESS);
4337 		} else {
4338 			err = dev_map_generic_redirect(fwd, skb, xdp_prog);
4339 		}
4340 		if (unlikely(err))
4341 			goto err;
4342 		break;
4343 	case BPF_MAP_TYPE_XSKMAP:
4344 		err = xsk_generic_rcv(fwd, xdp);
4345 		if (err)
4346 			goto err;
4347 		consume_skb(skb);
4348 		break;
4349 	case BPF_MAP_TYPE_CPUMAP:
4350 		err = cpu_map_generic_redirect(fwd, skb);
4351 		if (unlikely(err))
4352 			goto err;
4353 		break;
4354 	default:
4355 		err = -EBADRQC;
4356 		goto err;
4357 	}
4358 
4359 	_trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4360 	return 0;
4361 err:
4362 	_trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4363 	return err;
4364 }
4365 
xdp_do_generic_redirect(struct net_device * dev,struct sk_buff * skb,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4366 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
4367 			    struct xdp_buff *xdp, struct bpf_prog *xdp_prog)
4368 {
4369 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4370 	enum bpf_map_type map_type = ri->map_type;
4371 	void *fwd = ri->tgt_value;
4372 	u32 map_id = ri->map_id;
4373 	int err;
4374 
4375 	ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4376 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4377 
4378 	if (map_type == BPF_MAP_TYPE_UNSPEC && map_id == INT_MAX) {
4379 		fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
4380 		if (unlikely(!fwd)) {
4381 			err = -EINVAL;
4382 			goto err;
4383 		}
4384 
4385 		err = xdp_ok_fwd_dev(fwd, skb->len);
4386 		if (unlikely(err))
4387 			goto err;
4388 
4389 		skb->dev = fwd;
4390 		_trace_xdp_redirect(dev, xdp_prog, ri->tgt_index);
4391 		generic_xdp_tx(skb, xdp_prog);
4392 		return 0;
4393 	}
4394 
4395 	return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, fwd, map_type, map_id);
4396 err:
4397 	_trace_xdp_redirect_err(dev, xdp_prog, ri->tgt_index, err);
4398 	return err;
4399 }
4400 
BPF_CALL_2(bpf_xdp_redirect,u32,ifindex,u64,flags)4401 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
4402 {
4403 	struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4404 
4405 	if (unlikely(flags))
4406 		return XDP_ABORTED;
4407 
4408 	/* NB! Map type UNSPEC and map_id == INT_MAX (never generated
4409 	 * by map_idr) is used for ifindex based XDP redirect.
4410 	 */
4411 	ri->tgt_index = ifindex;
4412 	ri->map_id = INT_MAX;
4413 	ri->map_type = BPF_MAP_TYPE_UNSPEC;
4414 
4415 	return XDP_REDIRECT;
4416 }
4417 
4418 static const struct bpf_func_proto bpf_xdp_redirect_proto = {
4419 	.func           = bpf_xdp_redirect,
4420 	.gpl_only       = false,
4421 	.ret_type       = RET_INTEGER,
4422 	.arg1_type      = ARG_ANYTHING,
4423 	.arg2_type      = ARG_ANYTHING,
4424 };
4425 
BPF_CALL_3(bpf_xdp_redirect_map,struct bpf_map *,map,u32,ifindex,u64,flags)4426 BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex,
4427 	   u64, flags)
4428 {
4429 	return map->ops->map_redirect(map, ifindex, flags);
4430 }
4431 
4432 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
4433 	.func           = bpf_xdp_redirect_map,
4434 	.gpl_only       = false,
4435 	.ret_type       = RET_INTEGER,
4436 	.arg1_type      = ARG_CONST_MAP_PTR,
4437 	.arg2_type      = ARG_ANYTHING,
4438 	.arg3_type      = ARG_ANYTHING,
4439 };
4440 
bpf_skb_copy(void * dst_buff,const void * skb,unsigned long off,unsigned long len)4441 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
4442 				  unsigned long off, unsigned long len)
4443 {
4444 	void *ptr = skb_header_pointer(skb, off, len, dst_buff);
4445 
4446 	if (unlikely(!ptr))
4447 		return len;
4448 	if (ptr != dst_buff)
4449 		memcpy(dst_buff, ptr, len);
4450 
4451 	return 0;
4452 }
4453 
BPF_CALL_5(bpf_skb_event_output,struct sk_buff *,skb,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)4454 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
4455 	   u64, flags, void *, meta, u64, meta_size)
4456 {
4457 	u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
4458 
4459 	if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
4460 		return -EINVAL;
4461 	if (unlikely(!skb || skb_size > skb->len))
4462 		return -EFAULT;
4463 
4464 	return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
4465 				bpf_skb_copy);
4466 }
4467 
4468 static const struct bpf_func_proto bpf_skb_event_output_proto = {
4469 	.func		= bpf_skb_event_output,
4470 	.gpl_only	= true,
4471 	.ret_type	= RET_INTEGER,
4472 	.arg1_type	= ARG_PTR_TO_CTX,
4473 	.arg2_type	= ARG_CONST_MAP_PTR,
4474 	.arg3_type	= ARG_ANYTHING,
4475 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4476 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
4477 };
4478 
4479 BTF_ID_LIST_SINGLE(bpf_skb_output_btf_ids, struct, sk_buff)
4480 
4481 const struct bpf_func_proto bpf_skb_output_proto = {
4482 	.func		= bpf_skb_event_output,
4483 	.gpl_only	= true,
4484 	.ret_type	= RET_INTEGER,
4485 	.arg1_type	= ARG_PTR_TO_BTF_ID,
4486 	.arg1_btf_id	= &bpf_skb_output_btf_ids[0],
4487 	.arg2_type	= ARG_CONST_MAP_PTR,
4488 	.arg3_type	= ARG_ANYTHING,
4489 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4490 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
4491 };
4492 
bpf_tunnel_key_af(u64 flags)4493 static unsigned short bpf_tunnel_key_af(u64 flags)
4494 {
4495 	return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
4496 }
4497 
BPF_CALL_4(bpf_skb_get_tunnel_key,struct sk_buff *,skb,struct bpf_tunnel_key *,to,u32,size,u64,flags)4498 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
4499 	   u32, size, u64, flags)
4500 {
4501 	const struct ip_tunnel_info *info = skb_tunnel_info(skb);
4502 	u8 compat[sizeof(struct bpf_tunnel_key)];
4503 	void *to_orig = to;
4504 	int err;
4505 
4506 	if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6 |
4507 					 BPF_F_TUNINFO_FLAGS)))) {
4508 		err = -EINVAL;
4509 		goto err_clear;
4510 	}
4511 	if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
4512 		err = -EPROTO;
4513 		goto err_clear;
4514 	}
4515 	if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
4516 		err = -EINVAL;
4517 		switch (size) {
4518 		case offsetof(struct bpf_tunnel_key, local_ipv6[0]):
4519 		case offsetof(struct bpf_tunnel_key, tunnel_label):
4520 		case offsetof(struct bpf_tunnel_key, tunnel_ext):
4521 			goto set_compat;
4522 		case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
4523 			/* Fixup deprecated structure layouts here, so we have
4524 			 * a common path later on.
4525 			 */
4526 			if (ip_tunnel_info_af(info) != AF_INET)
4527 				goto err_clear;
4528 set_compat:
4529 			to = (struct bpf_tunnel_key *)compat;
4530 			break;
4531 		default:
4532 			goto err_clear;
4533 		}
4534 	}
4535 
4536 	to->tunnel_id = be64_to_cpu(info->key.tun_id);
4537 	to->tunnel_tos = info->key.tos;
4538 	to->tunnel_ttl = info->key.ttl;
4539 	if (flags & BPF_F_TUNINFO_FLAGS)
4540 		to->tunnel_flags = info->key.tun_flags;
4541 	else
4542 		to->tunnel_ext = 0;
4543 
4544 	if (flags & BPF_F_TUNINFO_IPV6) {
4545 		memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
4546 		       sizeof(to->remote_ipv6));
4547 		memcpy(to->local_ipv6, &info->key.u.ipv6.dst,
4548 		       sizeof(to->local_ipv6));
4549 		to->tunnel_label = be32_to_cpu(info->key.label);
4550 	} else {
4551 		to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
4552 		memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
4553 		to->local_ipv4 = be32_to_cpu(info->key.u.ipv4.dst);
4554 		memset(&to->local_ipv6[1], 0, sizeof(__u32) * 3);
4555 		to->tunnel_label = 0;
4556 	}
4557 
4558 	if (unlikely(size != sizeof(struct bpf_tunnel_key)))
4559 		memcpy(to_orig, to, size);
4560 
4561 	return 0;
4562 err_clear:
4563 	memset(to_orig, 0, size);
4564 	return err;
4565 }
4566 
4567 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
4568 	.func		= bpf_skb_get_tunnel_key,
4569 	.gpl_only	= false,
4570 	.ret_type	= RET_INTEGER,
4571 	.arg1_type	= ARG_PTR_TO_CTX,
4572 	.arg2_type	= ARG_PTR_TO_UNINIT_MEM,
4573 	.arg3_type	= ARG_CONST_SIZE,
4574 	.arg4_type	= ARG_ANYTHING,
4575 };
4576 
BPF_CALL_3(bpf_skb_get_tunnel_opt,struct sk_buff *,skb,u8 *,to,u32,size)4577 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
4578 {
4579 	const struct ip_tunnel_info *info = skb_tunnel_info(skb);
4580 	int err;
4581 
4582 	if (unlikely(!info ||
4583 		     !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
4584 		err = -ENOENT;
4585 		goto err_clear;
4586 	}
4587 	if (unlikely(size < info->options_len)) {
4588 		err = -ENOMEM;
4589 		goto err_clear;
4590 	}
4591 
4592 	ip_tunnel_info_opts_get(to, info);
4593 	if (size > info->options_len)
4594 		memset(to + info->options_len, 0, size - info->options_len);
4595 
4596 	return info->options_len;
4597 err_clear:
4598 	memset(to, 0, size);
4599 	return err;
4600 }
4601 
4602 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
4603 	.func		= bpf_skb_get_tunnel_opt,
4604 	.gpl_only	= false,
4605 	.ret_type	= RET_INTEGER,
4606 	.arg1_type	= ARG_PTR_TO_CTX,
4607 	.arg2_type	= ARG_PTR_TO_UNINIT_MEM,
4608 	.arg3_type	= ARG_CONST_SIZE,
4609 };
4610 
4611 static struct metadata_dst __percpu *md_dst;
4612 
BPF_CALL_4(bpf_skb_set_tunnel_key,struct sk_buff *,skb,const struct bpf_tunnel_key *,from,u32,size,u64,flags)4613 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
4614 	   const struct bpf_tunnel_key *, from, u32, size, u64, flags)
4615 {
4616 	struct metadata_dst *md = this_cpu_ptr(md_dst);
4617 	u8 compat[sizeof(struct bpf_tunnel_key)];
4618 	struct ip_tunnel_info *info;
4619 
4620 	if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
4621 			       BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER)))
4622 		return -EINVAL;
4623 	if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
4624 		switch (size) {
4625 		case offsetof(struct bpf_tunnel_key, local_ipv6[0]):
4626 		case offsetof(struct bpf_tunnel_key, tunnel_label):
4627 		case offsetof(struct bpf_tunnel_key, tunnel_ext):
4628 		case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
4629 			/* Fixup deprecated structure layouts here, so we have
4630 			 * a common path later on.
4631 			 */
4632 			memcpy(compat, from, size);
4633 			memset(compat + size, 0, sizeof(compat) - size);
4634 			from = (const struct bpf_tunnel_key *) compat;
4635 			break;
4636 		default:
4637 			return -EINVAL;
4638 		}
4639 	}
4640 	if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
4641 		     from->tunnel_ext))
4642 		return -EINVAL;
4643 
4644 	skb_dst_drop(skb);
4645 	dst_hold((struct dst_entry *) md);
4646 	skb_dst_set(skb, (struct dst_entry *) md);
4647 
4648 	info = &md->u.tun_info;
4649 	memset(info, 0, sizeof(*info));
4650 	info->mode = IP_TUNNEL_INFO_TX;
4651 
4652 	info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
4653 	if (flags & BPF_F_DONT_FRAGMENT)
4654 		info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
4655 	if (flags & BPF_F_ZERO_CSUM_TX)
4656 		info->key.tun_flags &= ~TUNNEL_CSUM;
4657 	if (flags & BPF_F_SEQ_NUMBER)
4658 		info->key.tun_flags |= TUNNEL_SEQ;
4659 
4660 	info->key.tun_id = cpu_to_be64(from->tunnel_id);
4661 	info->key.tos = from->tunnel_tos;
4662 	info->key.ttl = from->tunnel_ttl;
4663 
4664 	if (flags & BPF_F_TUNINFO_IPV6) {
4665 		info->mode |= IP_TUNNEL_INFO_IPV6;
4666 		memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
4667 		       sizeof(from->remote_ipv6));
4668 		memcpy(&info->key.u.ipv6.src, from->local_ipv6,
4669 		       sizeof(from->local_ipv6));
4670 		info->key.label = cpu_to_be32(from->tunnel_label) &
4671 				  IPV6_FLOWLABEL_MASK;
4672 	} else {
4673 		info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
4674 		info->key.u.ipv4.src = cpu_to_be32(from->local_ipv4);
4675 		info->key.flow_flags = FLOWI_FLAG_ANYSRC;
4676 	}
4677 
4678 	return 0;
4679 }
4680 
4681 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
4682 	.func		= bpf_skb_set_tunnel_key,
4683 	.gpl_only	= false,
4684 	.ret_type	= RET_INTEGER,
4685 	.arg1_type	= ARG_PTR_TO_CTX,
4686 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4687 	.arg3_type	= ARG_CONST_SIZE,
4688 	.arg4_type	= ARG_ANYTHING,
4689 };
4690 
BPF_CALL_3(bpf_skb_set_tunnel_opt,struct sk_buff *,skb,const u8 *,from,u32,size)4691 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
4692 	   const u8 *, from, u32, size)
4693 {
4694 	struct ip_tunnel_info *info = skb_tunnel_info(skb);
4695 	const struct metadata_dst *md = this_cpu_ptr(md_dst);
4696 
4697 	if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
4698 		return -EINVAL;
4699 	if (unlikely(size > IP_TUNNEL_OPTS_MAX))
4700 		return -ENOMEM;
4701 
4702 	ip_tunnel_info_opts_set(info, from, size, TUNNEL_OPTIONS_PRESENT);
4703 
4704 	return 0;
4705 }
4706 
4707 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
4708 	.func		= bpf_skb_set_tunnel_opt,
4709 	.gpl_only	= false,
4710 	.ret_type	= RET_INTEGER,
4711 	.arg1_type	= ARG_PTR_TO_CTX,
4712 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4713 	.arg3_type	= ARG_CONST_SIZE,
4714 };
4715 
4716 static const struct bpf_func_proto *
bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)4717 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
4718 {
4719 	if (!md_dst) {
4720 		struct metadata_dst __percpu *tmp;
4721 
4722 		tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
4723 						METADATA_IP_TUNNEL,
4724 						GFP_KERNEL);
4725 		if (!tmp)
4726 			return NULL;
4727 		if (cmpxchg(&md_dst, NULL, tmp))
4728 			metadata_dst_free_percpu(tmp);
4729 	}
4730 
4731 	switch (which) {
4732 	case BPF_FUNC_skb_set_tunnel_key:
4733 		return &bpf_skb_set_tunnel_key_proto;
4734 	case BPF_FUNC_skb_set_tunnel_opt:
4735 		return &bpf_skb_set_tunnel_opt_proto;
4736 	default:
4737 		return NULL;
4738 	}
4739 }
4740 
BPF_CALL_3(bpf_skb_under_cgroup,struct sk_buff *,skb,struct bpf_map *,map,u32,idx)4741 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
4742 	   u32, idx)
4743 {
4744 	struct bpf_array *array = container_of(map, struct bpf_array, map);
4745 	struct cgroup *cgrp;
4746 	struct sock *sk;
4747 
4748 	sk = skb_to_full_sk(skb);
4749 	if (!sk || !sk_fullsock(sk))
4750 		return -ENOENT;
4751 	if (unlikely(idx >= array->map.max_entries))
4752 		return -E2BIG;
4753 
4754 	cgrp = READ_ONCE(array->ptrs[idx]);
4755 	if (unlikely(!cgrp))
4756 		return -EAGAIN;
4757 
4758 	return sk_under_cgroup_hierarchy(sk, cgrp);
4759 }
4760 
4761 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
4762 	.func		= bpf_skb_under_cgroup,
4763 	.gpl_only	= false,
4764 	.ret_type	= RET_INTEGER,
4765 	.arg1_type	= ARG_PTR_TO_CTX,
4766 	.arg2_type	= ARG_CONST_MAP_PTR,
4767 	.arg3_type	= ARG_ANYTHING,
4768 };
4769 
4770 #ifdef CONFIG_SOCK_CGROUP_DATA
__bpf_sk_cgroup_id(struct sock * sk)4771 static inline u64 __bpf_sk_cgroup_id(struct sock *sk)
4772 {
4773 	struct cgroup *cgrp;
4774 
4775 	sk = sk_to_full_sk(sk);
4776 	if (!sk || !sk_fullsock(sk))
4777 		return 0;
4778 
4779 	cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4780 	return cgroup_id(cgrp);
4781 }
4782 
BPF_CALL_1(bpf_skb_cgroup_id,const struct sk_buff *,skb)4783 BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb)
4784 {
4785 	return __bpf_sk_cgroup_id(skb->sk);
4786 }
4787 
4788 static const struct bpf_func_proto bpf_skb_cgroup_id_proto = {
4789 	.func           = bpf_skb_cgroup_id,
4790 	.gpl_only       = false,
4791 	.ret_type       = RET_INTEGER,
4792 	.arg1_type      = ARG_PTR_TO_CTX,
4793 };
4794 
__bpf_sk_ancestor_cgroup_id(struct sock * sk,int ancestor_level)4795 static inline u64 __bpf_sk_ancestor_cgroup_id(struct sock *sk,
4796 					      int ancestor_level)
4797 {
4798 	struct cgroup *ancestor;
4799 	struct cgroup *cgrp;
4800 
4801 	sk = sk_to_full_sk(sk);
4802 	if (!sk || !sk_fullsock(sk))
4803 		return 0;
4804 
4805 	cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4806 	ancestor = cgroup_ancestor(cgrp, ancestor_level);
4807 	if (!ancestor)
4808 		return 0;
4809 
4810 	return cgroup_id(ancestor);
4811 }
4812 
BPF_CALL_2(bpf_skb_ancestor_cgroup_id,const struct sk_buff *,skb,int,ancestor_level)4813 BPF_CALL_2(bpf_skb_ancestor_cgroup_id, const struct sk_buff *, skb, int,
4814 	   ancestor_level)
4815 {
4816 	return __bpf_sk_ancestor_cgroup_id(skb->sk, ancestor_level);
4817 }
4818 
4819 static const struct bpf_func_proto bpf_skb_ancestor_cgroup_id_proto = {
4820 	.func           = bpf_skb_ancestor_cgroup_id,
4821 	.gpl_only       = false,
4822 	.ret_type       = RET_INTEGER,
4823 	.arg1_type      = ARG_PTR_TO_CTX,
4824 	.arg2_type      = ARG_ANYTHING,
4825 };
4826 
BPF_CALL_1(bpf_sk_cgroup_id,struct sock *,sk)4827 BPF_CALL_1(bpf_sk_cgroup_id, struct sock *, sk)
4828 {
4829 	return __bpf_sk_cgroup_id(sk);
4830 }
4831 
4832 static const struct bpf_func_proto bpf_sk_cgroup_id_proto = {
4833 	.func           = bpf_sk_cgroup_id,
4834 	.gpl_only       = false,
4835 	.ret_type       = RET_INTEGER,
4836 	.arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4837 };
4838 
BPF_CALL_2(bpf_sk_ancestor_cgroup_id,struct sock *,sk,int,ancestor_level)4839 BPF_CALL_2(bpf_sk_ancestor_cgroup_id, struct sock *, sk, int, ancestor_level)
4840 {
4841 	return __bpf_sk_ancestor_cgroup_id(sk, ancestor_level);
4842 }
4843 
4844 static const struct bpf_func_proto bpf_sk_ancestor_cgroup_id_proto = {
4845 	.func           = bpf_sk_ancestor_cgroup_id,
4846 	.gpl_only       = false,
4847 	.ret_type       = RET_INTEGER,
4848 	.arg1_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4849 	.arg2_type      = ARG_ANYTHING,
4850 };
4851 #endif
4852 
bpf_xdp_copy(void * dst,const void * ctx,unsigned long off,unsigned long len)4853 static unsigned long bpf_xdp_copy(void *dst, const void *ctx,
4854 				  unsigned long off, unsigned long len)
4855 {
4856 	struct xdp_buff *xdp = (struct xdp_buff *)ctx;
4857 
4858 	bpf_xdp_copy_buf(xdp, off, dst, len, false);
4859 	return 0;
4860 }
4861 
BPF_CALL_5(bpf_xdp_event_output,struct xdp_buff *,xdp,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)4862 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
4863 	   u64, flags, void *, meta, u64, meta_size)
4864 {
4865 	u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
4866 
4867 	if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
4868 		return -EINVAL;
4869 
4870 	if (unlikely(!xdp || xdp_size > xdp_get_buff_len(xdp)))
4871 		return -EFAULT;
4872 
4873 	return bpf_event_output(map, flags, meta, meta_size, xdp,
4874 				xdp_size, bpf_xdp_copy);
4875 }
4876 
4877 static const struct bpf_func_proto bpf_xdp_event_output_proto = {
4878 	.func		= bpf_xdp_event_output,
4879 	.gpl_only	= true,
4880 	.ret_type	= RET_INTEGER,
4881 	.arg1_type	= ARG_PTR_TO_CTX,
4882 	.arg2_type	= ARG_CONST_MAP_PTR,
4883 	.arg3_type	= ARG_ANYTHING,
4884 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4885 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
4886 };
4887 
4888 BTF_ID_LIST_SINGLE(bpf_xdp_output_btf_ids, struct, xdp_buff)
4889 
4890 const struct bpf_func_proto bpf_xdp_output_proto = {
4891 	.func		= bpf_xdp_event_output,
4892 	.gpl_only	= true,
4893 	.ret_type	= RET_INTEGER,
4894 	.arg1_type	= ARG_PTR_TO_BTF_ID,
4895 	.arg1_btf_id	= &bpf_xdp_output_btf_ids[0],
4896 	.arg2_type	= ARG_CONST_MAP_PTR,
4897 	.arg3_type	= ARG_ANYTHING,
4898 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4899 	.arg5_type	= ARG_CONST_SIZE_OR_ZERO,
4900 };
4901 
BPF_CALL_1(bpf_get_socket_cookie,struct sk_buff *,skb)4902 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
4903 {
4904 	return skb->sk ? __sock_gen_cookie(skb->sk) : 0;
4905 }
4906 
4907 static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
4908 	.func           = bpf_get_socket_cookie,
4909 	.gpl_only       = false,
4910 	.ret_type       = RET_INTEGER,
4911 	.arg1_type      = ARG_PTR_TO_CTX,
4912 };
4913 
BPF_CALL_1(bpf_get_socket_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)4914 BPF_CALL_1(bpf_get_socket_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
4915 {
4916 	return __sock_gen_cookie(ctx->sk);
4917 }
4918 
4919 static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = {
4920 	.func		= bpf_get_socket_cookie_sock_addr,
4921 	.gpl_only	= false,
4922 	.ret_type	= RET_INTEGER,
4923 	.arg1_type	= ARG_PTR_TO_CTX,
4924 };
4925 
BPF_CALL_1(bpf_get_socket_cookie_sock,struct sock *,ctx)4926 BPF_CALL_1(bpf_get_socket_cookie_sock, struct sock *, ctx)
4927 {
4928 	return __sock_gen_cookie(ctx);
4929 }
4930 
4931 static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
4932 	.func		= bpf_get_socket_cookie_sock,
4933 	.gpl_only	= false,
4934 	.ret_type	= RET_INTEGER,
4935 	.arg1_type	= ARG_PTR_TO_CTX,
4936 };
4937 
BPF_CALL_1(bpf_get_socket_ptr_cookie,struct sock *,sk)4938 BPF_CALL_1(bpf_get_socket_ptr_cookie, struct sock *, sk)
4939 {
4940 	return sk ? sock_gen_cookie(sk) : 0;
4941 }
4942 
4943 const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = {
4944 	.func		= bpf_get_socket_ptr_cookie,
4945 	.gpl_only	= false,
4946 	.ret_type	= RET_INTEGER,
4947 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4948 };
4949 
BPF_CALL_1(bpf_get_socket_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)4950 BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
4951 {
4952 	return __sock_gen_cookie(ctx->sk);
4953 }
4954 
4955 static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = {
4956 	.func		= bpf_get_socket_cookie_sock_ops,
4957 	.gpl_only	= false,
4958 	.ret_type	= RET_INTEGER,
4959 	.arg1_type	= ARG_PTR_TO_CTX,
4960 };
4961 
__bpf_get_netns_cookie(struct sock * sk)4962 static u64 __bpf_get_netns_cookie(struct sock *sk)
4963 {
4964 	const struct net *net = sk ? sock_net(sk) : &init_net;
4965 
4966 	return net->net_cookie;
4967 }
4968 
BPF_CALL_1(bpf_get_netns_cookie_sock,struct sock *,ctx)4969 BPF_CALL_1(bpf_get_netns_cookie_sock, struct sock *, ctx)
4970 {
4971 	return __bpf_get_netns_cookie(ctx);
4972 }
4973 
4974 static const struct bpf_func_proto bpf_get_netns_cookie_sock_proto = {
4975 	.func		= bpf_get_netns_cookie_sock,
4976 	.gpl_only	= false,
4977 	.ret_type	= RET_INTEGER,
4978 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
4979 };
4980 
BPF_CALL_1(bpf_get_netns_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)4981 BPF_CALL_1(bpf_get_netns_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
4982 {
4983 	return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
4984 }
4985 
4986 static const struct bpf_func_proto bpf_get_netns_cookie_sock_addr_proto = {
4987 	.func		= bpf_get_netns_cookie_sock_addr,
4988 	.gpl_only	= false,
4989 	.ret_type	= RET_INTEGER,
4990 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
4991 };
4992 
BPF_CALL_1(bpf_get_netns_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)4993 BPF_CALL_1(bpf_get_netns_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
4994 {
4995 	return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
4996 }
4997 
4998 static const struct bpf_func_proto bpf_get_netns_cookie_sock_ops_proto = {
4999 	.func		= bpf_get_netns_cookie_sock_ops,
5000 	.gpl_only	= false,
5001 	.ret_type	= RET_INTEGER,
5002 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
5003 };
5004 
BPF_CALL_1(bpf_get_netns_cookie_sk_msg,struct sk_msg *,ctx)5005 BPF_CALL_1(bpf_get_netns_cookie_sk_msg, struct sk_msg *, ctx)
5006 {
5007 	return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
5008 }
5009 
5010 static const struct bpf_func_proto bpf_get_netns_cookie_sk_msg_proto = {
5011 	.func		= bpf_get_netns_cookie_sk_msg,
5012 	.gpl_only	= false,
5013 	.ret_type	= RET_INTEGER,
5014 	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
5015 };
5016 
BPF_CALL_1(bpf_get_socket_uid,struct sk_buff *,skb)5017 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
5018 {
5019 	struct sock *sk = sk_to_full_sk(skb->sk);
5020 	kuid_t kuid;
5021 
5022 	if (!sk || !sk_fullsock(sk))
5023 		return overflowuid;
5024 	kuid = sock_net_uid(sock_net(sk), sk);
5025 	return from_kuid_munged(sock_net(sk)->user_ns, kuid);
5026 }
5027 
5028 static const struct bpf_func_proto bpf_get_socket_uid_proto = {
5029 	.func           = bpf_get_socket_uid,
5030 	.gpl_only       = false,
5031 	.ret_type       = RET_INTEGER,
5032 	.arg1_type      = ARG_PTR_TO_CTX,
5033 };
5034 
sol_socket_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5035 static int sol_socket_sockopt(struct sock *sk, int optname,
5036 			      char *optval, int *optlen,
5037 			      bool getopt)
5038 {
5039 	switch (optname) {
5040 	case SO_REUSEADDR:
5041 	case SO_SNDBUF:
5042 	case SO_RCVBUF:
5043 	case SO_KEEPALIVE:
5044 	case SO_PRIORITY:
5045 	case SO_REUSEPORT:
5046 	case SO_RCVLOWAT:
5047 	case SO_MARK:
5048 	case SO_MAX_PACING_RATE:
5049 	case SO_BINDTOIFINDEX:
5050 	case SO_TXREHASH:
5051 		if (*optlen != sizeof(int))
5052 			return -EINVAL;
5053 		break;
5054 	case SO_BINDTODEVICE:
5055 		break;
5056 	default:
5057 		return -EINVAL;
5058 	}
5059 
5060 	if (getopt) {
5061 		if (optname == SO_BINDTODEVICE)
5062 			return -EINVAL;
5063 		return sk_getsockopt(sk, SOL_SOCKET, optname,
5064 				     KERNEL_SOCKPTR(optval),
5065 				     KERNEL_SOCKPTR(optlen));
5066 	}
5067 
5068 	return sk_setsockopt(sk, SOL_SOCKET, optname,
5069 			     KERNEL_SOCKPTR(optval), *optlen);
5070 }
5071 
bpf_sol_tcp_setsockopt(struct sock * sk,int optname,char * optval,int optlen)5072 static int bpf_sol_tcp_setsockopt(struct sock *sk, int optname,
5073 				  char *optval, int optlen)
5074 {
5075 	struct tcp_sock *tp = tcp_sk(sk);
5076 	unsigned long timeout;
5077 	int val;
5078 
5079 	if (optlen != sizeof(int))
5080 		return -EINVAL;
5081 
5082 	val = *(int *)optval;
5083 
5084 	/* Only some options are supported */
5085 	switch (optname) {
5086 	case TCP_BPF_IW:
5087 		if (val <= 0 || tp->data_segs_out > tp->syn_data)
5088 			return -EINVAL;
5089 		tcp_snd_cwnd_set(tp, val);
5090 		break;
5091 	case TCP_BPF_SNDCWND_CLAMP:
5092 		if (val <= 0)
5093 			return -EINVAL;
5094 		tp->snd_cwnd_clamp = val;
5095 		tp->snd_ssthresh = val;
5096 		break;
5097 	case TCP_BPF_DELACK_MAX:
5098 		timeout = usecs_to_jiffies(val);
5099 		if (timeout > TCP_DELACK_MAX ||
5100 		    timeout < TCP_TIMEOUT_MIN)
5101 			return -EINVAL;
5102 		inet_csk(sk)->icsk_delack_max = timeout;
5103 		break;
5104 	case TCP_BPF_RTO_MIN:
5105 		timeout = usecs_to_jiffies(val);
5106 		if (timeout > TCP_RTO_MIN ||
5107 		    timeout < TCP_TIMEOUT_MIN)
5108 			return -EINVAL;
5109 		inet_csk(sk)->icsk_rto_min = timeout;
5110 		break;
5111 	default:
5112 		return -EINVAL;
5113 	}
5114 
5115 	return 0;
5116 }
5117 
sol_tcp_sockopt_congestion(struct sock * sk,char * optval,int * optlen,bool getopt)5118 static int sol_tcp_sockopt_congestion(struct sock *sk, char *optval,
5119 				      int *optlen, bool getopt)
5120 {
5121 	struct tcp_sock *tp;
5122 	int ret;
5123 
5124 	if (*optlen < 2)
5125 		return -EINVAL;
5126 
5127 	if (getopt) {
5128 		if (!inet_csk(sk)->icsk_ca_ops)
5129 			return -EINVAL;
5130 		/* BPF expects NULL-terminated tcp-cc string */
5131 		optval[--(*optlen)] = '\0';
5132 		return do_tcp_getsockopt(sk, SOL_TCP, TCP_CONGESTION,
5133 					 KERNEL_SOCKPTR(optval),
5134 					 KERNEL_SOCKPTR(optlen));
5135 	}
5136 
5137 	/* "cdg" is the only cc that alloc a ptr
5138 	 * in inet_csk_ca area.  The bpf-tcp-cc may
5139 	 * overwrite this ptr after switching to cdg.
5140 	 */
5141 	if (*optlen >= sizeof("cdg") - 1 && !strncmp("cdg", optval, *optlen))
5142 		return -ENOTSUPP;
5143 
5144 	/* It stops this looping
5145 	 *
5146 	 * .init => bpf_setsockopt(tcp_cc) => .init =>
5147 	 * bpf_setsockopt(tcp_cc)" => .init => ....
5148 	 *
5149 	 * The second bpf_setsockopt(tcp_cc) is not allowed
5150 	 * in order to break the loop when both .init
5151 	 * are the same bpf prog.
5152 	 *
5153 	 * This applies even the second bpf_setsockopt(tcp_cc)
5154 	 * does not cause a loop.  This limits only the first
5155 	 * '.init' can call bpf_setsockopt(TCP_CONGESTION) to
5156 	 * pick a fallback cc (eg. peer does not support ECN)
5157 	 * and the second '.init' cannot fallback to
5158 	 * another.
5159 	 */
5160 	tp = tcp_sk(sk);
5161 	if (tp->bpf_chg_cc_inprogress)
5162 		return -EBUSY;
5163 
5164 	tp->bpf_chg_cc_inprogress = 1;
5165 	ret = do_tcp_setsockopt(sk, SOL_TCP, TCP_CONGESTION,
5166 				KERNEL_SOCKPTR(optval), *optlen);
5167 	tp->bpf_chg_cc_inprogress = 0;
5168 	return ret;
5169 }
5170 
sol_tcp_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5171 static int sol_tcp_sockopt(struct sock *sk, int optname,
5172 			   char *optval, int *optlen,
5173 			   bool getopt)
5174 {
5175 	if (sk->sk_prot->setsockopt != tcp_setsockopt)
5176 		return -EINVAL;
5177 
5178 	switch (optname) {
5179 	case TCP_NODELAY:
5180 	case TCP_MAXSEG:
5181 	case TCP_KEEPIDLE:
5182 	case TCP_KEEPINTVL:
5183 	case TCP_KEEPCNT:
5184 	case TCP_SYNCNT:
5185 	case TCP_WINDOW_CLAMP:
5186 	case TCP_THIN_LINEAR_TIMEOUTS:
5187 	case TCP_USER_TIMEOUT:
5188 	case TCP_NOTSENT_LOWAT:
5189 	case TCP_SAVE_SYN:
5190 		if (*optlen != sizeof(int))
5191 			return -EINVAL;
5192 		break;
5193 	case TCP_CONGESTION:
5194 		return sol_tcp_sockopt_congestion(sk, optval, optlen, getopt);
5195 	case TCP_SAVED_SYN:
5196 		if (*optlen < 1)
5197 			return -EINVAL;
5198 		break;
5199 	default:
5200 		if (getopt)
5201 			return -EINVAL;
5202 		return bpf_sol_tcp_setsockopt(sk, optname, optval, *optlen);
5203 	}
5204 
5205 	if (getopt) {
5206 		if (optname == TCP_SAVED_SYN) {
5207 			struct tcp_sock *tp = tcp_sk(sk);
5208 
5209 			if (!tp->saved_syn ||
5210 			    *optlen > tcp_saved_syn_len(tp->saved_syn))
5211 				return -EINVAL;
5212 			memcpy(optval, tp->saved_syn->data, *optlen);
5213 			/* It cannot free tp->saved_syn here because it
5214 			 * does not know if the user space still needs it.
5215 			 */
5216 			return 0;
5217 		}
5218 
5219 		return do_tcp_getsockopt(sk, SOL_TCP, optname,
5220 					 KERNEL_SOCKPTR(optval),
5221 					 KERNEL_SOCKPTR(optlen));
5222 	}
5223 
5224 	return do_tcp_setsockopt(sk, SOL_TCP, optname,
5225 				 KERNEL_SOCKPTR(optval), *optlen);
5226 }
5227 
sol_ip_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5228 static int sol_ip_sockopt(struct sock *sk, int optname,
5229 			  char *optval, int *optlen,
5230 			  bool getopt)
5231 {
5232 	if (sk->sk_family != AF_INET)
5233 		return -EINVAL;
5234 
5235 	switch (optname) {
5236 	case IP_TOS:
5237 		if (*optlen != sizeof(int))
5238 			return -EINVAL;
5239 		break;
5240 	default:
5241 		return -EINVAL;
5242 	}
5243 
5244 	if (getopt)
5245 		return do_ip_getsockopt(sk, SOL_IP, optname,
5246 					KERNEL_SOCKPTR(optval),
5247 					KERNEL_SOCKPTR(optlen));
5248 
5249 	return do_ip_setsockopt(sk, SOL_IP, optname,
5250 				KERNEL_SOCKPTR(optval), *optlen);
5251 }
5252 
sol_ipv6_sockopt(struct sock * sk,int optname,char * optval,int * optlen,bool getopt)5253 static int sol_ipv6_sockopt(struct sock *sk, int optname,
5254 			    char *optval, int *optlen,
5255 			    bool getopt)
5256 {
5257 	if (sk->sk_family != AF_INET6)
5258 		return -EINVAL;
5259 
5260 	switch (optname) {
5261 	case IPV6_TCLASS:
5262 	case IPV6_AUTOFLOWLABEL:
5263 		if (*optlen != sizeof(int))
5264 			return -EINVAL;
5265 		break;
5266 	default:
5267 		return -EINVAL;
5268 	}
5269 
5270 	if (getopt)
5271 		return ipv6_bpf_stub->ipv6_getsockopt(sk, SOL_IPV6, optname,
5272 						      KERNEL_SOCKPTR(optval),
5273 						      KERNEL_SOCKPTR(optlen));
5274 
5275 	return ipv6_bpf_stub->ipv6_setsockopt(sk, SOL_IPV6, optname,
5276 					      KERNEL_SOCKPTR(optval), *optlen);
5277 }
5278 
__bpf_setsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5279 static int __bpf_setsockopt(struct sock *sk, int level, int optname,
5280 			    char *optval, int optlen)
5281 {
5282 	if (!sk_fullsock(sk))
5283 		return -EINVAL;
5284 
5285 	if (level == SOL_SOCKET)
5286 		return sol_socket_sockopt(sk, optname, optval, &optlen, false);
5287 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_IP)
5288 		return sol_ip_sockopt(sk, optname, optval, &optlen, false);
5289 	else if (IS_ENABLED(CONFIG_IPV6) && level == SOL_IPV6)
5290 		return sol_ipv6_sockopt(sk, optname, optval, &optlen, false);
5291 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP)
5292 		return sol_tcp_sockopt(sk, optname, optval, &optlen, false);
5293 
5294 	return -EINVAL;
5295 }
5296 
_bpf_setsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5297 static int _bpf_setsockopt(struct sock *sk, int level, int optname,
5298 			   char *optval, int optlen)
5299 {
5300 	if (sk_fullsock(sk))
5301 		sock_owned_by_me(sk);
5302 	return __bpf_setsockopt(sk, level, optname, optval, optlen);
5303 }
5304 
__bpf_getsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5305 static int __bpf_getsockopt(struct sock *sk, int level, int optname,
5306 			    char *optval, int optlen)
5307 {
5308 	int err, saved_optlen = optlen;
5309 
5310 	if (!sk_fullsock(sk)) {
5311 		err = -EINVAL;
5312 		goto done;
5313 	}
5314 
5315 	if (level == SOL_SOCKET)
5316 		err = sol_socket_sockopt(sk, optname, optval, &optlen, true);
5317 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP)
5318 		err = sol_tcp_sockopt(sk, optname, optval, &optlen, true);
5319 	else if (IS_ENABLED(CONFIG_INET) && level == SOL_IP)
5320 		err = sol_ip_sockopt(sk, optname, optval, &optlen, true);
5321 	else if (IS_ENABLED(CONFIG_IPV6) && level == SOL_IPV6)
5322 		err = sol_ipv6_sockopt(sk, optname, optval, &optlen, true);
5323 	else
5324 		err = -EINVAL;
5325 
5326 done:
5327 	if (err)
5328 		optlen = 0;
5329 	if (optlen < saved_optlen)
5330 		memset(optval + optlen, 0, saved_optlen - optlen);
5331 	return err;
5332 }
5333 
_bpf_getsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5334 static int _bpf_getsockopt(struct sock *sk, int level, int optname,
5335 			   char *optval, int optlen)
5336 {
5337 	if (sk_fullsock(sk))
5338 		sock_owned_by_me(sk);
5339 	return __bpf_getsockopt(sk, level, optname, optval, optlen);
5340 }
5341 
BPF_CALL_5(bpf_sk_setsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5342 BPF_CALL_5(bpf_sk_setsockopt, struct sock *, sk, int, level,
5343 	   int, optname, char *, optval, int, optlen)
5344 {
5345 	return _bpf_setsockopt(sk, level, optname, optval, optlen);
5346 }
5347 
5348 const struct bpf_func_proto bpf_sk_setsockopt_proto = {
5349 	.func		= bpf_sk_setsockopt,
5350 	.gpl_only	= false,
5351 	.ret_type	= RET_INTEGER,
5352 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5353 	.arg2_type	= ARG_ANYTHING,
5354 	.arg3_type	= ARG_ANYTHING,
5355 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5356 	.arg5_type	= ARG_CONST_SIZE,
5357 };
5358 
BPF_CALL_5(bpf_sk_getsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5359 BPF_CALL_5(bpf_sk_getsockopt, struct sock *, sk, int, level,
5360 	   int, optname, char *, optval, int, optlen)
5361 {
5362 	return _bpf_getsockopt(sk, level, optname, optval, optlen);
5363 }
5364 
5365 const struct bpf_func_proto bpf_sk_getsockopt_proto = {
5366 	.func		= bpf_sk_getsockopt,
5367 	.gpl_only	= false,
5368 	.ret_type	= RET_INTEGER,
5369 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5370 	.arg2_type	= ARG_ANYTHING,
5371 	.arg3_type	= ARG_ANYTHING,
5372 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5373 	.arg5_type	= ARG_CONST_SIZE,
5374 };
5375 
BPF_CALL_5(bpf_unlocked_sk_setsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5376 BPF_CALL_5(bpf_unlocked_sk_setsockopt, struct sock *, sk, int, level,
5377 	   int, optname, char *, optval, int, optlen)
5378 {
5379 	return __bpf_setsockopt(sk, level, optname, optval, optlen);
5380 }
5381 
5382 const struct bpf_func_proto bpf_unlocked_sk_setsockopt_proto = {
5383 	.func		= bpf_unlocked_sk_setsockopt,
5384 	.gpl_only	= false,
5385 	.ret_type	= RET_INTEGER,
5386 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5387 	.arg2_type	= ARG_ANYTHING,
5388 	.arg3_type	= ARG_ANYTHING,
5389 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5390 	.arg5_type	= ARG_CONST_SIZE,
5391 };
5392 
BPF_CALL_5(bpf_unlocked_sk_getsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5393 BPF_CALL_5(bpf_unlocked_sk_getsockopt, struct sock *, sk, int, level,
5394 	   int, optname, char *, optval, int, optlen)
5395 {
5396 	return __bpf_getsockopt(sk, level, optname, optval, optlen);
5397 }
5398 
5399 const struct bpf_func_proto bpf_unlocked_sk_getsockopt_proto = {
5400 	.func		= bpf_unlocked_sk_getsockopt,
5401 	.gpl_only	= false,
5402 	.ret_type	= RET_INTEGER,
5403 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5404 	.arg2_type	= ARG_ANYTHING,
5405 	.arg3_type	= ARG_ANYTHING,
5406 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5407 	.arg5_type	= ARG_CONST_SIZE,
5408 };
5409 
BPF_CALL_5(bpf_sock_addr_setsockopt,struct bpf_sock_addr_kern *,ctx,int,level,int,optname,char *,optval,int,optlen)5410 BPF_CALL_5(bpf_sock_addr_setsockopt, struct bpf_sock_addr_kern *, ctx,
5411 	   int, level, int, optname, char *, optval, int, optlen)
5412 {
5413 	return _bpf_setsockopt(ctx->sk, level, optname, optval, optlen);
5414 }
5415 
5416 static const struct bpf_func_proto bpf_sock_addr_setsockopt_proto = {
5417 	.func		= bpf_sock_addr_setsockopt,
5418 	.gpl_only	= false,
5419 	.ret_type	= RET_INTEGER,
5420 	.arg1_type	= ARG_PTR_TO_CTX,
5421 	.arg2_type	= ARG_ANYTHING,
5422 	.arg3_type	= ARG_ANYTHING,
5423 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5424 	.arg5_type	= ARG_CONST_SIZE,
5425 };
5426 
BPF_CALL_5(bpf_sock_addr_getsockopt,struct bpf_sock_addr_kern *,ctx,int,level,int,optname,char *,optval,int,optlen)5427 BPF_CALL_5(bpf_sock_addr_getsockopt, struct bpf_sock_addr_kern *, ctx,
5428 	   int, level, int, optname, char *, optval, int, optlen)
5429 {
5430 	return _bpf_getsockopt(ctx->sk, level, optname, optval, optlen);
5431 }
5432 
5433 static const struct bpf_func_proto bpf_sock_addr_getsockopt_proto = {
5434 	.func		= bpf_sock_addr_getsockopt,
5435 	.gpl_only	= false,
5436 	.ret_type	= RET_INTEGER,
5437 	.arg1_type	= ARG_PTR_TO_CTX,
5438 	.arg2_type	= ARG_ANYTHING,
5439 	.arg3_type	= ARG_ANYTHING,
5440 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5441 	.arg5_type	= ARG_CONST_SIZE,
5442 };
5443 
BPF_CALL_5(bpf_sock_ops_setsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)5444 BPF_CALL_5(bpf_sock_ops_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
5445 	   int, level, int, optname, char *, optval, int, optlen)
5446 {
5447 	return _bpf_setsockopt(bpf_sock->sk, level, optname, optval, optlen);
5448 }
5449 
5450 static const struct bpf_func_proto bpf_sock_ops_setsockopt_proto = {
5451 	.func		= bpf_sock_ops_setsockopt,
5452 	.gpl_only	= false,
5453 	.ret_type	= RET_INTEGER,
5454 	.arg1_type	= ARG_PTR_TO_CTX,
5455 	.arg2_type	= ARG_ANYTHING,
5456 	.arg3_type	= ARG_ANYTHING,
5457 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5458 	.arg5_type	= ARG_CONST_SIZE,
5459 };
5460 
bpf_sock_ops_get_syn(struct bpf_sock_ops_kern * bpf_sock,int optname,const u8 ** start)5461 static int bpf_sock_ops_get_syn(struct bpf_sock_ops_kern *bpf_sock,
5462 				int optname, const u8 **start)
5463 {
5464 	struct sk_buff *syn_skb = bpf_sock->syn_skb;
5465 	const u8 *hdr_start;
5466 	int ret;
5467 
5468 	if (syn_skb) {
5469 		/* sk is a request_sock here */
5470 
5471 		if (optname == TCP_BPF_SYN) {
5472 			hdr_start = syn_skb->data;
5473 			ret = tcp_hdrlen(syn_skb);
5474 		} else if (optname == TCP_BPF_SYN_IP) {
5475 			hdr_start = skb_network_header(syn_skb);
5476 			ret = skb_network_header_len(syn_skb) +
5477 				tcp_hdrlen(syn_skb);
5478 		} else {
5479 			/* optname == TCP_BPF_SYN_MAC */
5480 			hdr_start = skb_mac_header(syn_skb);
5481 			ret = skb_mac_header_len(syn_skb) +
5482 				skb_network_header_len(syn_skb) +
5483 				tcp_hdrlen(syn_skb);
5484 		}
5485 	} else {
5486 		struct sock *sk = bpf_sock->sk;
5487 		struct saved_syn *saved_syn;
5488 
5489 		if (sk->sk_state == TCP_NEW_SYN_RECV)
5490 			/* synack retransmit. bpf_sock->syn_skb will
5491 			 * not be available.  It has to resort to
5492 			 * saved_syn (if it is saved).
5493 			 */
5494 			saved_syn = inet_reqsk(sk)->saved_syn;
5495 		else
5496 			saved_syn = tcp_sk(sk)->saved_syn;
5497 
5498 		if (!saved_syn)
5499 			return -ENOENT;
5500 
5501 		if (optname == TCP_BPF_SYN) {
5502 			hdr_start = saved_syn->data +
5503 				saved_syn->mac_hdrlen +
5504 				saved_syn->network_hdrlen;
5505 			ret = saved_syn->tcp_hdrlen;
5506 		} else if (optname == TCP_BPF_SYN_IP) {
5507 			hdr_start = saved_syn->data +
5508 				saved_syn->mac_hdrlen;
5509 			ret = saved_syn->network_hdrlen +
5510 				saved_syn->tcp_hdrlen;
5511 		} else {
5512 			/* optname == TCP_BPF_SYN_MAC */
5513 
5514 			/* TCP_SAVE_SYN may not have saved the mac hdr */
5515 			if (!saved_syn->mac_hdrlen)
5516 				return -ENOENT;
5517 
5518 			hdr_start = saved_syn->data;
5519 			ret = saved_syn->mac_hdrlen +
5520 				saved_syn->network_hdrlen +
5521 				saved_syn->tcp_hdrlen;
5522 		}
5523 	}
5524 
5525 	*start = hdr_start;
5526 	return ret;
5527 }
5528 
BPF_CALL_5(bpf_sock_ops_getsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)5529 BPF_CALL_5(bpf_sock_ops_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
5530 	   int, level, int, optname, char *, optval, int, optlen)
5531 {
5532 	if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP &&
5533 	    optname >= TCP_BPF_SYN && optname <= TCP_BPF_SYN_MAC) {
5534 		int ret, copy_len = 0;
5535 		const u8 *start;
5536 
5537 		ret = bpf_sock_ops_get_syn(bpf_sock, optname, &start);
5538 		if (ret > 0) {
5539 			copy_len = ret;
5540 			if (optlen < copy_len) {
5541 				copy_len = optlen;
5542 				ret = -ENOSPC;
5543 			}
5544 
5545 			memcpy(optval, start, copy_len);
5546 		}
5547 
5548 		/* Zero out unused buffer at the end */
5549 		memset(optval + copy_len, 0, optlen - copy_len);
5550 
5551 		return ret;
5552 	}
5553 
5554 	return _bpf_getsockopt(bpf_sock->sk, level, optname, optval, optlen);
5555 }
5556 
5557 static const struct bpf_func_proto bpf_sock_ops_getsockopt_proto = {
5558 	.func		= bpf_sock_ops_getsockopt,
5559 	.gpl_only	= false,
5560 	.ret_type	= RET_INTEGER,
5561 	.arg1_type	= ARG_PTR_TO_CTX,
5562 	.arg2_type	= ARG_ANYTHING,
5563 	.arg3_type	= ARG_ANYTHING,
5564 	.arg4_type	= ARG_PTR_TO_UNINIT_MEM,
5565 	.arg5_type	= ARG_CONST_SIZE,
5566 };
5567 
BPF_CALL_2(bpf_sock_ops_cb_flags_set,struct bpf_sock_ops_kern *,bpf_sock,int,argval)5568 BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock,
5569 	   int, argval)
5570 {
5571 	struct sock *sk = bpf_sock->sk;
5572 	int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS;
5573 
5574 	if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk))
5575 		return -EINVAL;
5576 
5577 	tcp_sk(sk)->bpf_sock_ops_cb_flags = val;
5578 
5579 	return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS);
5580 }
5581 
5582 static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = {
5583 	.func		= bpf_sock_ops_cb_flags_set,
5584 	.gpl_only	= false,
5585 	.ret_type	= RET_INTEGER,
5586 	.arg1_type	= ARG_PTR_TO_CTX,
5587 	.arg2_type	= ARG_ANYTHING,
5588 };
5589 
5590 const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
5591 EXPORT_SYMBOL_GPL(ipv6_bpf_stub);
5592 
BPF_CALL_3(bpf_bind,struct bpf_sock_addr_kern *,ctx,struct sockaddr *,addr,int,addr_len)5593 BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr,
5594 	   int, addr_len)
5595 {
5596 #ifdef CONFIG_INET
5597 	struct sock *sk = ctx->sk;
5598 	u32 flags = BIND_FROM_BPF;
5599 	int err;
5600 
5601 	err = -EINVAL;
5602 	if (addr_len < offsetofend(struct sockaddr, sa_family))
5603 		return err;
5604 	if (addr->sa_family == AF_INET) {
5605 		if (addr_len < sizeof(struct sockaddr_in))
5606 			return err;
5607 		if (((struct sockaddr_in *)addr)->sin_port == htons(0))
5608 			flags |= BIND_FORCE_ADDRESS_NO_PORT;
5609 		return __inet_bind(sk, addr, addr_len, flags);
5610 #if IS_ENABLED(CONFIG_IPV6)
5611 	} else if (addr->sa_family == AF_INET6) {
5612 		if (addr_len < SIN6_LEN_RFC2133)
5613 			return err;
5614 		if (((struct sockaddr_in6 *)addr)->sin6_port == htons(0))
5615 			flags |= BIND_FORCE_ADDRESS_NO_PORT;
5616 		/* ipv6_bpf_stub cannot be NULL, since it's called from
5617 		 * bpf_cgroup_inet6_connect hook and ipv6 is already loaded
5618 		 */
5619 		return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, flags);
5620 #endif /* CONFIG_IPV6 */
5621 	}
5622 #endif /* CONFIG_INET */
5623 
5624 	return -EAFNOSUPPORT;
5625 }
5626 
5627 static const struct bpf_func_proto bpf_bind_proto = {
5628 	.func		= bpf_bind,
5629 	.gpl_only	= false,
5630 	.ret_type	= RET_INTEGER,
5631 	.arg1_type	= ARG_PTR_TO_CTX,
5632 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5633 	.arg3_type	= ARG_CONST_SIZE,
5634 };
5635 
5636 #ifdef CONFIG_XFRM
BPF_CALL_5(bpf_skb_get_xfrm_state,struct sk_buff *,skb,u32,index,struct bpf_xfrm_state *,to,u32,size,u64,flags)5637 BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index,
5638 	   struct bpf_xfrm_state *, to, u32, size, u64, flags)
5639 {
5640 	const struct sec_path *sp = skb_sec_path(skb);
5641 	const struct xfrm_state *x;
5642 
5643 	if (!sp || unlikely(index >= sp->len || flags))
5644 		goto err_clear;
5645 
5646 	x = sp->xvec[index];
5647 
5648 	if (unlikely(size != sizeof(struct bpf_xfrm_state)))
5649 		goto err_clear;
5650 
5651 	to->reqid = x->props.reqid;
5652 	to->spi = x->id.spi;
5653 	to->family = x->props.family;
5654 	to->ext = 0;
5655 
5656 	if (to->family == AF_INET6) {
5657 		memcpy(to->remote_ipv6, x->props.saddr.a6,
5658 		       sizeof(to->remote_ipv6));
5659 	} else {
5660 		to->remote_ipv4 = x->props.saddr.a4;
5661 		memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
5662 	}
5663 
5664 	return 0;
5665 err_clear:
5666 	memset(to, 0, size);
5667 	return -EINVAL;
5668 }
5669 
5670 static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = {
5671 	.func		= bpf_skb_get_xfrm_state,
5672 	.gpl_only	= false,
5673 	.ret_type	= RET_INTEGER,
5674 	.arg1_type	= ARG_PTR_TO_CTX,
5675 	.arg2_type	= ARG_ANYTHING,
5676 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
5677 	.arg4_type	= ARG_CONST_SIZE,
5678 	.arg5_type	= ARG_ANYTHING,
5679 };
5680 #endif
5681 
5682 #if IS_ENABLED(CONFIG_INET) || IS_ENABLED(CONFIG_IPV6)
bpf_fib_set_fwd_params(struct bpf_fib_lookup * params,const struct neighbour * neigh,const struct net_device * dev,u32 mtu)5683 static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params,
5684 				  const struct neighbour *neigh,
5685 				  const struct net_device *dev, u32 mtu)
5686 {
5687 	memcpy(params->dmac, neigh->ha, ETH_ALEN);
5688 	memcpy(params->smac, dev->dev_addr, ETH_ALEN);
5689 	params->h_vlan_TCI = 0;
5690 	params->h_vlan_proto = 0;
5691 	if (mtu)
5692 		params->mtu_result = mtu; /* union with tot_len */
5693 
5694 	return 0;
5695 }
5696 #endif
5697 
5698 #if IS_ENABLED(CONFIG_INET)
bpf_ipv4_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)5699 static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
5700 			       u32 flags, bool check_mtu)
5701 {
5702 	struct fib_nh_common *nhc;
5703 	struct in_device *in_dev;
5704 	struct neighbour *neigh;
5705 	struct net_device *dev;
5706 	struct fib_result res;
5707 	struct flowi4 fl4;
5708 	u32 mtu = 0;
5709 	int err;
5710 
5711 	dev = dev_get_by_index_rcu(net, params->ifindex);
5712 	if (unlikely(!dev))
5713 		return -ENODEV;
5714 
5715 	/* verify forwarding is enabled on this interface */
5716 	in_dev = __in_dev_get_rcu(dev);
5717 	if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev)))
5718 		return BPF_FIB_LKUP_RET_FWD_DISABLED;
5719 
5720 	if (flags & BPF_FIB_LOOKUP_OUTPUT) {
5721 		fl4.flowi4_iif = 1;
5722 		fl4.flowi4_oif = params->ifindex;
5723 	} else {
5724 		fl4.flowi4_iif = params->ifindex;
5725 		fl4.flowi4_oif = 0;
5726 	}
5727 	fl4.flowi4_tos = params->tos & IPTOS_RT_MASK;
5728 	fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
5729 	fl4.flowi4_flags = 0;
5730 
5731 	fl4.flowi4_proto = params->l4_protocol;
5732 	fl4.daddr = params->ipv4_dst;
5733 	fl4.saddr = params->ipv4_src;
5734 	fl4.fl4_sport = params->sport;
5735 	fl4.fl4_dport = params->dport;
5736 	fl4.flowi4_multipath_hash = 0;
5737 
5738 	if (flags & BPF_FIB_LOOKUP_DIRECT) {
5739 		u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
5740 		struct fib_table *tb;
5741 
5742 		tb = fib_get_table(net, tbid);
5743 		if (unlikely(!tb))
5744 			return BPF_FIB_LKUP_RET_NOT_FWDED;
5745 
5746 		err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
5747 	} else {
5748 		fl4.flowi4_mark = 0;
5749 		fl4.flowi4_secid = 0;
5750 		fl4.flowi4_tun_key.tun_id = 0;
5751 		fl4.flowi4_uid = sock_net_uid(net, NULL);
5752 
5753 		err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF);
5754 	}
5755 
5756 	if (err) {
5757 		/* map fib lookup errors to RTN_ type */
5758 		if (err == -EINVAL)
5759 			return BPF_FIB_LKUP_RET_BLACKHOLE;
5760 		if (err == -EHOSTUNREACH)
5761 			return BPF_FIB_LKUP_RET_UNREACHABLE;
5762 		if (err == -EACCES)
5763 			return BPF_FIB_LKUP_RET_PROHIBIT;
5764 
5765 		return BPF_FIB_LKUP_RET_NOT_FWDED;
5766 	}
5767 
5768 	if (res.type != RTN_UNICAST)
5769 		return BPF_FIB_LKUP_RET_NOT_FWDED;
5770 
5771 	if (fib_info_num_path(res.fi) > 1)
5772 		fib_select_path(net, &res, &fl4, NULL);
5773 
5774 	if (check_mtu) {
5775 		mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst);
5776 		if (params->tot_len > mtu) {
5777 			params->mtu_result = mtu; /* union with tot_len */
5778 			return BPF_FIB_LKUP_RET_FRAG_NEEDED;
5779 		}
5780 	}
5781 
5782 	nhc = res.nhc;
5783 
5784 	/* do not handle lwt encaps right now */
5785 	if (nhc->nhc_lwtstate)
5786 		return BPF_FIB_LKUP_RET_UNSUPP_LWT;
5787 
5788 	dev = nhc->nhc_dev;
5789 
5790 	params->rt_metric = res.fi->fib_priority;
5791 	params->ifindex = dev->ifindex;
5792 
5793 	/* xdp and cls_bpf programs are run in RCU-bh so
5794 	 * rcu_read_lock_bh is not needed here
5795 	 */
5796 	if (likely(nhc->nhc_gw_family != AF_INET6)) {
5797 		if (nhc->nhc_gw_family)
5798 			params->ipv4_dst = nhc->nhc_gw.ipv4;
5799 
5800 		neigh = __ipv4_neigh_lookup_noref(dev,
5801 						 (__force u32)params->ipv4_dst);
5802 	} else {
5803 		struct in6_addr *dst = (struct in6_addr *)params->ipv6_dst;
5804 
5805 		params->family = AF_INET6;
5806 		*dst = nhc->nhc_gw.ipv6;
5807 		neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
5808 	}
5809 
5810 	if (!neigh)
5811 		return BPF_FIB_LKUP_RET_NO_NEIGH;
5812 
5813 	return bpf_fib_set_fwd_params(params, neigh, dev, mtu);
5814 }
5815 #endif
5816 
5817 #if IS_ENABLED(CONFIG_IPV6)
bpf_ipv6_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)5818 static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
5819 			       u32 flags, bool check_mtu)
5820 {
5821 	struct in6_addr *src = (struct in6_addr *) params->ipv6_src;
5822 	struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst;
5823 	struct fib6_result res = {};
5824 	struct neighbour *neigh;
5825 	struct net_device *dev;
5826 	struct inet6_dev *idev;
5827 	struct flowi6 fl6;
5828 	int strict = 0;
5829 	int oif, err;
5830 	u32 mtu = 0;
5831 
5832 	/* link local addresses are never forwarded */
5833 	if (rt6_need_strict(dst) || rt6_need_strict(src))
5834 		return BPF_FIB_LKUP_RET_NOT_FWDED;
5835 
5836 	dev = dev_get_by_index_rcu(net, params->ifindex);
5837 	if (unlikely(!dev))
5838 		return -ENODEV;
5839 
5840 	idev = __in6_dev_get_safely(dev);
5841 	if (unlikely(!idev || !idev->cnf.forwarding))
5842 		return BPF_FIB_LKUP_RET_FWD_DISABLED;
5843 
5844 	if (flags & BPF_FIB_LOOKUP_OUTPUT) {
5845 		fl6.flowi6_iif = 1;
5846 		oif = fl6.flowi6_oif = params->ifindex;
5847 	} else {
5848 		oif = fl6.flowi6_iif = params->ifindex;
5849 		fl6.flowi6_oif = 0;
5850 		strict = RT6_LOOKUP_F_HAS_SADDR;
5851 	}
5852 	fl6.flowlabel = params->flowinfo;
5853 	fl6.flowi6_scope = 0;
5854 	fl6.flowi6_flags = 0;
5855 	fl6.mp_hash = 0;
5856 
5857 	fl6.flowi6_proto = params->l4_protocol;
5858 	fl6.daddr = *dst;
5859 	fl6.saddr = *src;
5860 	fl6.fl6_sport = params->sport;
5861 	fl6.fl6_dport = params->dport;
5862 
5863 	if (flags & BPF_FIB_LOOKUP_DIRECT) {
5864 		u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
5865 		struct fib6_table *tb;
5866 
5867 		tb = ipv6_stub->fib6_get_table(net, tbid);
5868 		if (unlikely(!tb))
5869 			return BPF_FIB_LKUP_RET_NOT_FWDED;
5870 
5871 		err = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, &res,
5872 						   strict);
5873 	} else {
5874 		fl6.flowi6_mark = 0;
5875 		fl6.flowi6_secid = 0;
5876 		fl6.flowi6_tun_key.tun_id = 0;
5877 		fl6.flowi6_uid = sock_net_uid(net, NULL);
5878 
5879 		err = ipv6_stub->fib6_lookup(net, oif, &fl6, &res, strict);
5880 	}
5881 
5882 	if (unlikely(err || IS_ERR_OR_NULL(res.f6i) ||
5883 		     res.f6i == net->ipv6.fib6_null_entry))
5884 		return BPF_FIB_LKUP_RET_NOT_FWDED;
5885 
5886 	switch (res.fib6_type) {
5887 	/* only unicast is forwarded */
5888 	case RTN_UNICAST:
5889 		break;
5890 	case RTN_BLACKHOLE:
5891 		return BPF_FIB_LKUP_RET_BLACKHOLE;
5892 	case RTN_UNREACHABLE:
5893 		return BPF_FIB_LKUP_RET_UNREACHABLE;
5894 	case RTN_PROHIBIT:
5895 		return BPF_FIB_LKUP_RET_PROHIBIT;
5896 	default:
5897 		return BPF_FIB_LKUP_RET_NOT_FWDED;
5898 	}
5899 
5900 	ipv6_stub->fib6_select_path(net, &res, &fl6, fl6.flowi6_oif,
5901 				    fl6.flowi6_oif != 0, NULL, strict);
5902 
5903 	if (check_mtu) {
5904 		mtu = ipv6_stub->ip6_mtu_from_fib6(&res, dst, src);
5905 		if (params->tot_len > mtu) {
5906 			params->mtu_result = mtu; /* union with tot_len */
5907 			return BPF_FIB_LKUP_RET_FRAG_NEEDED;
5908 		}
5909 	}
5910 
5911 	if (res.nh->fib_nh_lws)
5912 		return BPF_FIB_LKUP_RET_UNSUPP_LWT;
5913 
5914 	if (res.nh->fib_nh_gw_family)
5915 		*dst = res.nh->fib_nh_gw6;
5916 
5917 	dev = res.nh->fib_nh_dev;
5918 	params->rt_metric = res.f6i->fib6_metric;
5919 	params->ifindex = dev->ifindex;
5920 
5921 	/* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is
5922 	 * not needed here.
5923 	 */
5924 	neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
5925 	if (!neigh)
5926 		return BPF_FIB_LKUP_RET_NO_NEIGH;
5927 
5928 	return bpf_fib_set_fwd_params(params, neigh, dev, mtu);
5929 }
5930 #endif
5931 
BPF_CALL_4(bpf_xdp_fib_lookup,struct xdp_buff *,ctx,struct bpf_fib_lookup *,params,int,plen,u32,flags)5932 BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx,
5933 	   struct bpf_fib_lookup *, params, int, plen, u32, flags)
5934 {
5935 	if (plen < sizeof(*params))
5936 		return -EINVAL;
5937 
5938 	if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT))
5939 		return -EINVAL;
5940 
5941 	switch (params->family) {
5942 #if IS_ENABLED(CONFIG_INET)
5943 	case AF_INET:
5944 		return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params,
5945 					   flags, true);
5946 #endif
5947 #if IS_ENABLED(CONFIG_IPV6)
5948 	case AF_INET6:
5949 		return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params,
5950 					   flags, true);
5951 #endif
5952 	}
5953 	return -EAFNOSUPPORT;
5954 }
5955 
5956 static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = {
5957 	.func		= bpf_xdp_fib_lookup,
5958 	.gpl_only	= true,
5959 	.ret_type	= RET_INTEGER,
5960 	.arg1_type      = ARG_PTR_TO_CTX,
5961 	.arg2_type      = ARG_PTR_TO_MEM,
5962 	.arg3_type      = ARG_CONST_SIZE,
5963 	.arg4_type	= ARG_ANYTHING,
5964 };
5965 
BPF_CALL_4(bpf_skb_fib_lookup,struct sk_buff *,skb,struct bpf_fib_lookup *,params,int,plen,u32,flags)5966 BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
5967 	   struct bpf_fib_lookup *, params, int, plen, u32, flags)
5968 {
5969 	struct net *net = dev_net(skb->dev);
5970 	int rc = -EAFNOSUPPORT;
5971 	bool check_mtu = false;
5972 
5973 	if (plen < sizeof(*params))
5974 		return -EINVAL;
5975 
5976 	if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT))
5977 		return -EINVAL;
5978 
5979 	if (params->tot_len)
5980 		check_mtu = true;
5981 
5982 	switch (params->family) {
5983 #if IS_ENABLED(CONFIG_INET)
5984 	case AF_INET:
5985 		rc = bpf_ipv4_fib_lookup(net, params, flags, check_mtu);
5986 		break;
5987 #endif
5988 #if IS_ENABLED(CONFIG_IPV6)
5989 	case AF_INET6:
5990 		rc = bpf_ipv6_fib_lookup(net, params, flags, check_mtu);
5991 		break;
5992 #endif
5993 	}
5994 
5995 	if (rc == BPF_FIB_LKUP_RET_SUCCESS && !check_mtu) {
5996 		struct net_device *dev;
5997 
5998 		/* When tot_len isn't provided by user, check skb
5999 		 * against MTU of FIB lookup resulting net_device
6000 		 */
6001 		dev = dev_get_by_index_rcu(net, params->ifindex);
6002 		if (!is_skb_forwardable(dev, skb))
6003 			rc = BPF_FIB_LKUP_RET_FRAG_NEEDED;
6004 
6005 		params->mtu_result = dev->mtu; /* union with tot_len */
6006 	}
6007 
6008 	return rc;
6009 }
6010 
6011 static const struct bpf_func_proto bpf_skb_fib_lookup_proto = {
6012 	.func		= bpf_skb_fib_lookup,
6013 	.gpl_only	= true,
6014 	.ret_type	= RET_INTEGER,
6015 	.arg1_type      = ARG_PTR_TO_CTX,
6016 	.arg2_type      = ARG_PTR_TO_MEM,
6017 	.arg3_type      = ARG_CONST_SIZE,
6018 	.arg4_type	= ARG_ANYTHING,
6019 };
6020 
__dev_via_ifindex(struct net_device * dev_curr,u32 ifindex)6021 static struct net_device *__dev_via_ifindex(struct net_device *dev_curr,
6022 					    u32 ifindex)
6023 {
6024 	struct net *netns = dev_net(dev_curr);
6025 
6026 	/* Non-redirect use-cases can use ifindex=0 and save ifindex lookup */
6027 	if (ifindex == 0)
6028 		return dev_curr;
6029 
6030 	return dev_get_by_index_rcu(netns, ifindex);
6031 }
6032 
BPF_CALL_5(bpf_skb_check_mtu,struct sk_buff *,skb,u32,ifindex,u32 *,mtu_len,s32,len_diff,u64,flags)6033 BPF_CALL_5(bpf_skb_check_mtu, struct sk_buff *, skb,
6034 	   u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
6035 {
6036 	int ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
6037 	struct net_device *dev = skb->dev;
6038 	int skb_len, dev_len;
6039 	int mtu;
6040 
6041 	if (unlikely(flags & ~(BPF_MTU_CHK_SEGS)))
6042 		return -EINVAL;
6043 
6044 	if (unlikely(flags & BPF_MTU_CHK_SEGS && (len_diff || *mtu_len)))
6045 		return -EINVAL;
6046 
6047 	dev = __dev_via_ifindex(dev, ifindex);
6048 	if (unlikely(!dev))
6049 		return -ENODEV;
6050 
6051 	mtu = READ_ONCE(dev->mtu);
6052 
6053 	dev_len = mtu + dev->hard_header_len;
6054 
6055 	/* If set use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
6056 	skb_len = *mtu_len ? *mtu_len + dev->hard_header_len : skb->len;
6057 
6058 	skb_len += len_diff; /* minus result pass check */
6059 	if (skb_len <= dev_len) {
6060 		ret = BPF_MTU_CHK_RET_SUCCESS;
6061 		goto out;
6062 	}
6063 	/* At this point, skb->len exceed MTU, but as it include length of all
6064 	 * segments, it can still be below MTU.  The SKB can possibly get
6065 	 * re-segmented in transmit path (see validate_xmit_skb).  Thus, user
6066 	 * must choose if segs are to be MTU checked.
6067 	 */
6068 	if (skb_is_gso(skb)) {
6069 		ret = BPF_MTU_CHK_RET_SUCCESS;
6070 
6071 		if (flags & BPF_MTU_CHK_SEGS &&
6072 		    !skb_gso_validate_network_len(skb, mtu))
6073 			ret = BPF_MTU_CHK_RET_SEGS_TOOBIG;
6074 	}
6075 out:
6076 	/* BPF verifier guarantees valid pointer */
6077 	*mtu_len = mtu;
6078 
6079 	return ret;
6080 }
6081 
BPF_CALL_5(bpf_xdp_check_mtu,struct xdp_buff *,xdp,u32,ifindex,u32 *,mtu_len,s32,len_diff,u64,flags)6082 BPF_CALL_5(bpf_xdp_check_mtu, struct xdp_buff *, xdp,
6083 	   u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
6084 {
6085 	struct net_device *dev = xdp->rxq->dev;
6086 	int xdp_len = xdp->data_end - xdp->data;
6087 	int ret = BPF_MTU_CHK_RET_SUCCESS;
6088 	int mtu, dev_len;
6089 
6090 	/* XDP variant doesn't support multi-buffer segment check (yet) */
6091 	if (unlikely(flags))
6092 		return -EINVAL;
6093 
6094 	dev = __dev_via_ifindex(dev, ifindex);
6095 	if (unlikely(!dev))
6096 		return -ENODEV;
6097 
6098 	mtu = READ_ONCE(dev->mtu);
6099 
6100 	/* Add L2-header as dev MTU is L3 size */
6101 	dev_len = mtu + dev->hard_header_len;
6102 
6103 	/* Use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
6104 	if (*mtu_len)
6105 		xdp_len = *mtu_len + dev->hard_header_len;
6106 
6107 	xdp_len += len_diff; /* minus result pass check */
6108 	if (xdp_len > dev_len)
6109 		ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
6110 
6111 	/* BPF verifier guarantees valid pointer */
6112 	*mtu_len = mtu;
6113 
6114 	return ret;
6115 }
6116 
6117 static const struct bpf_func_proto bpf_skb_check_mtu_proto = {
6118 	.func		= bpf_skb_check_mtu,
6119 	.gpl_only	= true,
6120 	.ret_type	= RET_INTEGER,
6121 	.arg1_type      = ARG_PTR_TO_CTX,
6122 	.arg2_type      = ARG_ANYTHING,
6123 	.arg3_type      = ARG_PTR_TO_INT,
6124 	.arg4_type      = ARG_ANYTHING,
6125 	.arg5_type      = ARG_ANYTHING,
6126 };
6127 
6128 static const struct bpf_func_proto bpf_xdp_check_mtu_proto = {
6129 	.func		= bpf_xdp_check_mtu,
6130 	.gpl_only	= true,
6131 	.ret_type	= RET_INTEGER,
6132 	.arg1_type      = ARG_PTR_TO_CTX,
6133 	.arg2_type      = ARG_ANYTHING,
6134 	.arg3_type      = ARG_PTR_TO_INT,
6135 	.arg4_type      = ARG_ANYTHING,
6136 	.arg5_type      = ARG_ANYTHING,
6137 };
6138 
6139 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
bpf_push_seg6_encap(struct sk_buff * skb,u32 type,void * hdr,u32 len)6140 static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
6141 {
6142 	int err;
6143 	struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr;
6144 
6145 	if (!seg6_validate_srh(srh, len, false))
6146 		return -EINVAL;
6147 
6148 	switch (type) {
6149 	case BPF_LWT_ENCAP_SEG6_INLINE:
6150 		if (skb->protocol != htons(ETH_P_IPV6))
6151 			return -EBADMSG;
6152 
6153 		err = seg6_do_srh_inline(skb, srh);
6154 		break;
6155 	case BPF_LWT_ENCAP_SEG6:
6156 		skb_reset_inner_headers(skb);
6157 		skb->encapsulation = 1;
6158 		err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6);
6159 		break;
6160 	default:
6161 		return -EINVAL;
6162 	}
6163 
6164 	bpf_compute_data_pointers(skb);
6165 	if (err)
6166 		return err;
6167 
6168 	skb_set_transport_header(skb, sizeof(struct ipv6hdr));
6169 
6170 	return seg6_lookup_nexthop(skb, NULL, 0);
6171 }
6172 #endif /* CONFIG_IPV6_SEG6_BPF */
6173 
6174 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
bpf_push_ip_encap(struct sk_buff * skb,void * hdr,u32 len,bool ingress)6175 static int bpf_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len,
6176 			     bool ingress)
6177 {
6178 	return bpf_lwt_push_ip_encap(skb, hdr, len, ingress);
6179 }
6180 #endif
6181 
BPF_CALL_4(bpf_lwt_in_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)6182 BPF_CALL_4(bpf_lwt_in_push_encap, struct sk_buff *, skb, u32, type, void *, hdr,
6183 	   u32, len)
6184 {
6185 	switch (type) {
6186 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
6187 	case BPF_LWT_ENCAP_SEG6:
6188 	case BPF_LWT_ENCAP_SEG6_INLINE:
6189 		return bpf_push_seg6_encap(skb, type, hdr, len);
6190 #endif
6191 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
6192 	case BPF_LWT_ENCAP_IP:
6193 		return bpf_push_ip_encap(skb, hdr, len, true /* ingress */);
6194 #endif
6195 	default:
6196 		return -EINVAL;
6197 	}
6198 }
6199 
BPF_CALL_4(bpf_lwt_xmit_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)6200 BPF_CALL_4(bpf_lwt_xmit_push_encap, struct sk_buff *, skb, u32, type,
6201 	   void *, hdr, u32, len)
6202 {
6203 	switch (type) {
6204 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
6205 	case BPF_LWT_ENCAP_IP:
6206 		return bpf_push_ip_encap(skb, hdr, len, false /* egress */);
6207 #endif
6208 	default:
6209 		return -EINVAL;
6210 	}
6211 }
6212 
6213 static const struct bpf_func_proto bpf_lwt_in_push_encap_proto = {
6214 	.func		= bpf_lwt_in_push_encap,
6215 	.gpl_only	= false,
6216 	.ret_type	= RET_INTEGER,
6217 	.arg1_type	= ARG_PTR_TO_CTX,
6218 	.arg2_type	= ARG_ANYTHING,
6219 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6220 	.arg4_type	= ARG_CONST_SIZE
6221 };
6222 
6223 static const struct bpf_func_proto bpf_lwt_xmit_push_encap_proto = {
6224 	.func		= bpf_lwt_xmit_push_encap,
6225 	.gpl_only	= false,
6226 	.ret_type	= RET_INTEGER,
6227 	.arg1_type	= ARG_PTR_TO_CTX,
6228 	.arg2_type	= ARG_ANYTHING,
6229 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6230 	.arg4_type	= ARG_CONST_SIZE
6231 };
6232 
6233 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
BPF_CALL_4(bpf_lwt_seg6_store_bytes,struct sk_buff *,skb,u32,offset,const void *,from,u32,len)6234 BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset,
6235 	   const void *, from, u32, len)
6236 {
6237 	struct seg6_bpf_srh_state *srh_state =
6238 		this_cpu_ptr(&seg6_bpf_srh_states);
6239 	struct ipv6_sr_hdr *srh = srh_state->srh;
6240 	void *srh_tlvs, *srh_end, *ptr;
6241 	int srhoff = 0;
6242 
6243 	if (srh == NULL)
6244 		return -EINVAL;
6245 
6246 	srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4));
6247 	srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen);
6248 
6249 	ptr = skb->data + offset;
6250 	if (ptr >= srh_tlvs && ptr + len <= srh_end)
6251 		srh_state->valid = false;
6252 	else if (ptr < (void *)&srh->flags ||
6253 		 ptr + len > (void *)&srh->segments)
6254 		return -EFAULT;
6255 
6256 	if (unlikely(bpf_try_make_writable(skb, offset + len)))
6257 		return -EFAULT;
6258 	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
6259 		return -EINVAL;
6260 	srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6261 
6262 	memcpy(skb->data + offset, from, len);
6263 	return 0;
6264 }
6265 
6266 static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = {
6267 	.func		= bpf_lwt_seg6_store_bytes,
6268 	.gpl_only	= false,
6269 	.ret_type	= RET_INTEGER,
6270 	.arg1_type	= ARG_PTR_TO_CTX,
6271 	.arg2_type	= ARG_ANYTHING,
6272 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6273 	.arg4_type	= ARG_CONST_SIZE
6274 };
6275 
bpf_update_srh_state(struct sk_buff * skb)6276 static void bpf_update_srh_state(struct sk_buff *skb)
6277 {
6278 	struct seg6_bpf_srh_state *srh_state =
6279 		this_cpu_ptr(&seg6_bpf_srh_states);
6280 	int srhoff = 0;
6281 
6282 	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) {
6283 		srh_state->srh = NULL;
6284 	} else {
6285 		srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6286 		srh_state->hdrlen = srh_state->srh->hdrlen << 3;
6287 		srh_state->valid = true;
6288 	}
6289 }
6290 
BPF_CALL_4(bpf_lwt_seg6_action,struct sk_buff *,skb,u32,action,void *,param,u32,param_len)6291 BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
6292 	   u32, action, void *, param, u32, param_len)
6293 {
6294 	struct seg6_bpf_srh_state *srh_state =
6295 		this_cpu_ptr(&seg6_bpf_srh_states);
6296 	int hdroff = 0;
6297 	int err;
6298 
6299 	switch (action) {
6300 	case SEG6_LOCAL_ACTION_END_X:
6301 		if (!seg6_bpf_has_valid_srh(skb))
6302 			return -EBADMSG;
6303 		if (param_len != sizeof(struct in6_addr))
6304 			return -EINVAL;
6305 		return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0);
6306 	case SEG6_LOCAL_ACTION_END_T:
6307 		if (!seg6_bpf_has_valid_srh(skb))
6308 			return -EBADMSG;
6309 		if (param_len != sizeof(int))
6310 			return -EINVAL;
6311 		return seg6_lookup_nexthop(skb, NULL, *(int *)param);
6312 	case SEG6_LOCAL_ACTION_END_DT6:
6313 		if (!seg6_bpf_has_valid_srh(skb))
6314 			return -EBADMSG;
6315 		if (param_len != sizeof(int))
6316 			return -EINVAL;
6317 
6318 		if (ipv6_find_hdr(skb, &hdroff, IPPROTO_IPV6, NULL, NULL) < 0)
6319 			return -EBADMSG;
6320 		if (!pskb_pull(skb, hdroff))
6321 			return -EBADMSG;
6322 
6323 		skb_postpull_rcsum(skb, skb_network_header(skb), hdroff);
6324 		skb_reset_network_header(skb);
6325 		skb_reset_transport_header(skb);
6326 		skb->encapsulation = 0;
6327 
6328 		bpf_compute_data_pointers(skb);
6329 		bpf_update_srh_state(skb);
6330 		return seg6_lookup_nexthop(skb, NULL, *(int *)param);
6331 	case SEG6_LOCAL_ACTION_END_B6:
6332 		if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
6333 			return -EBADMSG;
6334 		err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE,
6335 					  param, param_len);
6336 		if (!err)
6337 			bpf_update_srh_state(skb);
6338 
6339 		return err;
6340 	case SEG6_LOCAL_ACTION_END_B6_ENCAP:
6341 		if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
6342 			return -EBADMSG;
6343 		err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6,
6344 					  param, param_len);
6345 		if (!err)
6346 			bpf_update_srh_state(skb);
6347 
6348 		return err;
6349 	default:
6350 		return -EINVAL;
6351 	}
6352 }
6353 
6354 static const struct bpf_func_proto bpf_lwt_seg6_action_proto = {
6355 	.func		= bpf_lwt_seg6_action,
6356 	.gpl_only	= false,
6357 	.ret_type	= RET_INTEGER,
6358 	.arg1_type	= ARG_PTR_TO_CTX,
6359 	.arg2_type	= ARG_ANYTHING,
6360 	.arg3_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6361 	.arg4_type	= ARG_CONST_SIZE
6362 };
6363 
BPF_CALL_3(bpf_lwt_seg6_adjust_srh,struct sk_buff *,skb,u32,offset,s32,len)6364 BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
6365 	   s32, len)
6366 {
6367 	struct seg6_bpf_srh_state *srh_state =
6368 		this_cpu_ptr(&seg6_bpf_srh_states);
6369 	struct ipv6_sr_hdr *srh = srh_state->srh;
6370 	void *srh_end, *srh_tlvs, *ptr;
6371 	struct ipv6hdr *hdr;
6372 	int srhoff = 0;
6373 	int ret;
6374 
6375 	if (unlikely(srh == NULL))
6376 		return -EINVAL;
6377 
6378 	srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) +
6379 			((srh->first_segment + 1) << 4));
6380 	srh_end = (void *)((unsigned char *)srh + sizeof(*srh) +
6381 			srh_state->hdrlen);
6382 	ptr = skb->data + offset;
6383 
6384 	if (unlikely(ptr < srh_tlvs || ptr > srh_end))
6385 		return -EFAULT;
6386 	if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end))
6387 		return -EFAULT;
6388 
6389 	if (len > 0) {
6390 		ret = skb_cow_head(skb, len);
6391 		if (unlikely(ret < 0))
6392 			return ret;
6393 
6394 		ret = bpf_skb_net_hdr_push(skb, offset, len);
6395 	} else {
6396 		ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len);
6397 	}
6398 
6399 	bpf_compute_data_pointers(skb);
6400 	if (unlikely(ret < 0))
6401 		return ret;
6402 
6403 	hdr = (struct ipv6hdr *)skb->data;
6404 	hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
6405 
6406 	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
6407 		return -EINVAL;
6408 	srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6409 	srh_state->hdrlen += len;
6410 	srh_state->valid = false;
6411 	return 0;
6412 }
6413 
6414 static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = {
6415 	.func		= bpf_lwt_seg6_adjust_srh,
6416 	.gpl_only	= false,
6417 	.ret_type	= RET_INTEGER,
6418 	.arg1_type	= ARG_PTR_TO_CTX,
6419 	.arg2_type	= ARG_ANYTHING,
6420 	.arg3_type	= ARG_ANYTHING,
6421 };
6422 #endif /* CONFIG_IPV6_SEG6_BPF */
6423 
6424 #ifdef CONFIG_INET
sk_lookup(struct net * net,struct bpf_sock_tuple * tuple,int dif,int sdif,u8 family,u8 proto)6425 static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple,
6426 			      int dif, int sdif, u8 family, u8 proto)
6427 {
6428 	struct inet_hashinfo *hinfo = net->ipv4.tcp_death_row.hashinfo;
6429 	bool refcounted = false;
6430 	struct sock *sk = NULL;
6431 
6432 	if (family == AF_INET) {
6433 		__be32 src4 = tuple->ipv4.saddr;
6434 		__be32 dst4 = tuple->ipv4.daddr;
6435 
6436 		if (proto == IPPROTO_TCP)
6437 			sk = __inet_lookup(net, hinfo, NULL, 0,
6438 					   src4, tuple->ipv4.sport,
6439 					   dst4, tuple->ipv4.dport,
6440 					   dif, sdif, &refcounted);
6441 		else
6442 			sk = __udp4_lib_lookup(net, src4, tuple->ipv4.sport,
6443 					       dst4, tuple->ipv4.dport,
6444 					       dif, sdif, &udp_table, NULL);
6445 #if IS_ENABLED(CONFIG_IPV6)
6446 	} else {
6447 		struct in6_addr *src6 = (struct in6_addr *)&tuple->ipv6.saddr;
6448 		struct in6_addr *dst6 = (struct in6_addr *)&tuple->ipv6.daddr;
6449 
6450 		if (proto == IPPROTO_TCP)
6451 			sk = __inet6_lookup(net, hinfo, NULL, 0,
6452 					    src6, tuple->ipv6.sport,
6453 					    dst6, ntohs(tuple->ipv6.dport),
6454 					    dif, sdif, &refcounted);
6455 		else if (likely(ipv6_bpf_stub))
6456 			sk = ipv6_bpf_stub->udp6_lib_lookup(net,
6457 							    src6, tuple->ipv6.sport,
6458 							    dst6, tuple->ipv6.dport,
6459 							    dif, sdif,
6460 							    &udp_table, NULL);
6461 #endif
6462 	}
6463 
6464 	if (unlikely(sk && !refcounted && !sock_flag(sk, SOCK_RCU_FREE))) {
6465 		WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6466 		sk = NULL;
6467 	}
6468 	return sk;
6469 }
6470 
6471 /* bpf_skc_lookup performs the core lookup for different types of sockets,
6472  * taking a reference on the socket if it doesn't have the flag SOCK_RCU_FREE.
6473  */
6474 static struct sock *
__bpf_skc_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,struct net * caller_net,u32 ifindex,u8 proto,u64 netns_id,u64 flags)6475 __bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6476 		 struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
6477 		 u64 flags)
6478 {
6479 	struct sock *sk = NULL;
6480 	struct net *net;
6481 	u8 family;
6482 	int sdif;
6483 
6484 	if (len == sizeof(tuple->ipv4))
6485 		family = AF_INET;
6486 	else if (len == sizeof(tuple->ipv6))
6487 		family = AF_INET6;
6488 	else
6489 		return NULL;
6490 
6491 	if (unlikely(flags || !((s32)netns_id < 0 || netns_id <= S32_MAX)))
6492 		goto out;
6493 
6494 	if (family == AF_INET)
6495 		sdif = inet_sdif(skb);
6496 	else
6497 		sdif = inet6_sdif(skb);
6498 
6499 	if ((s32)netns_id < 0) {
6500 		net = caller_net;
6501 		sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
6502 	} else {
6503 		net = get_net_ns_by_id(caller_net, netns_id);
6504 		if (unlikely(!net))
6505 			goto out;
6506 		sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
6507 		put_net(net);
6508 	}
6509 
6510 out:
6511 	return sk;
6512 }
6513 
6514 static struct sock *
__bpf_sk_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,struct net * caller_net,u32 ifindex,u8 proto,u64 netns_id,u64 flags)6515 __bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6516 		struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
6517 		u64 flags)
6518 {
6519 	struct sock *sk = __bpf_skc_lookup(skb, tuple, len, caller_net,
6520 					   ifindex, proto, netns_id, flags);
6521 
6522 	if (sk) {
6523 		struct sock *sk2 = sk_to_full_sk(sk);
6524 
6525 		/* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
6526 		 * sock refcnt is decremented to prevent a request_sock leak.
6527 		 */
6528 		if (!sk_fullsock(sk2))
6529 			sk2 = NULL;
6530 		if (sk2 != sk) {
6531 			sock_gen_put(sk);
6532 			/* Ensure there is no need to bump sk2 refcnt */
6533 			if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
6534 				WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6535 				return NULL;
6536 			}
6537 			sk = sk2;
6538 		}
6539 	}
6540 
6541 	return sk;
6542 }
6543 
6544 static struct sock *
bpf_skc_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)6545 bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6546 	       u8 proto, u64 netns_id, u64 flags)
6547 {
6548 	struct net *caller_net;
6549 	int ifindex;
6550 
6551 	if (skb->dev) {
6552 		caller_net = dev_net(skb->dev);
6553 		ifindex = skb->dev->ifindex;
6554 	} else {
6555 		caller_net = sock_net(skb->sk);
6556 		ifindex = 0;
6557 	}
6558 
6559 	return __bpf_skc_lookup(skb, tuple, len, caller_net, ifindex, proto,
6560 				netns_id, flags);
6561 }
6562 
6563 static struct sock *
bpf_sk_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)6564 bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6565 	      u8 proto, u64 netns_id, u64 flags)
6566 {
6567 	struct sock *sk = bpf_skc_lookup(skb, tuple, len, proto, netns_id,
6568 					 flags);
6569 
6570 	if (sk) {
6571 		struct sock *sk2 = sk_to_full_sk(sk);
6572 
6573 		/* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
6574 		 * sock refcnt is decremented to prevent a request_sock leak.
6575 		 */
6576 		if (!sk_fullsock(sk2))
6577 			sk2 = NULL;
6578 		if (sk2 != sk) {
6579 			sock_gen_put(sk);
6580 			/* Ensure there is no need to bump sk2 refcnt */
6581 			if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
6582 				WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6583 				return NULL;
6584 			}
6585 			sk = sk2;
6586 		}
6587 	}
6588 
6589 	return sk;
6590 }
6591 
BPF_CALL_5(bpf_skc_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6592 BPF_CALL_5(bpf_skc_lookup_tcp, struct sk_buff *, skb,
6593 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6594 {
6595 	return (unsigned long)bpf_skc_lookup(skb, tuple, len, IPPROTO_TCP,
6596 					     netns_id, flags);
6597 }
6598 
6599 static const struct bpf_func_proto bpf_skc_lookup_tcp_proto = {
6600 	.func		= bpf_skc_lookup_tcp,
6601 	.gpl_only	= false,
6602 	.pkt_access	= true,
6603 	.ret_type	= RET_PTR_TO_SOCK_COMMON_OR_NULL,
6604 	.arg1_type	= ARG_PTR_TO_CTX,
6605 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6606 	.arg3_type	= ARG_CONST_SIZE,
6607 	.arg4_type	= ARG_ANYTHING,
6608 	.arg5_type	= ARG_ANYTHING,
6609 };
6610 
BPF_CALL_5(bpf_sk_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6611 BPF_CALL_5(bpf_sk_lookup_tcp, struct sk_buff *, skb,
6612 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6613 {
6614 	return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_TCP,
6615 					    netns_id, flags);
6616 }
6617 
6618 static const struct bpf_func_proto bpf_sk_lookup_tcp_proto = {
6619 	.func		= bpf_sk_lookup_tcp,
6620 	.gpl_only	= false,
6621 	.pkt_access	= true,
6622 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6623 	.arg1_type	= ARG_PTR_TO_CTX,
6624 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6625 	.arg3_type	= ARG_CONST_SIZE,
6626 	.arg4_type	= ARG_ANYTHING,
6627 	.arg5_type	= ARG_ANYTHING,
6628 };
6629 
BPF_CALL_5(bpf_sk_lookup_udp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6630 BPF_CALL_5(bpf_sk_lookup_udp, struct sk_buff *, skb,
6631 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6632 {
6633 	return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_UDP,
6634 					    netns_id, flags);
6635 }
6636 
6637 static const struct bpf_func_proto bpf_sk_lookup_udp_proto = {
6638 	.func		= bpf_sk_lookup_udp,
6639 	.gpl_only	= false,
6640 	.pkt_access	= true,
6641 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6642 	.arg1_type	= ARG_PTR_TO_CTX,
6643 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6644 	.arg3_type	= ARG_CONST_SIZE,
6645 	.arg4_type	= ARG_ANYTHING,
6646 	.arg5_type	= ARG_ANYTHING,
6647 };
6648 
BPF_CALL_1(bpf_sk_release,struct sock *,sk)6649 BPF_CALL_1(bpf_sk_release, struct sock *, sk)
6650 {
6651 	if (sk && sk_is_refcounted(sk))
6652 		sock_gen_put(sk);
6653 	return 0;
6654 }
6655 
6656 static const struct bpf_func_proto bpf_sk_release_proto = {
6657 	.func		= bpf_sk_release,
6658 	.gpl_only	= false,
6659 	.ret_type	= RET_INTEGER,
6660 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON | OBJ_RELEASE,
6661 };
6662 
BPF_CALL_5(bpf_xdp_sk_lookup_udp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6663 BPF_CALL_5(bpf_xdp_sk_lookup_udp, struct xdp_buff *, ctx,
6664 	   struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6665 {
6666 	struct net *caller_net = dev_net(ctx->rxq->dev);
6667 	int ifindex = ctx->rxq->dev->ifindex;
6668 
6669 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
6670 					      ifindex, IPPROTO_UDP, netns_id,
6671 					      flags);
6672 }
6673 
6674 static const struct bpf_func_proto bpf_xdp_sk_lookup_udp_proto = {
6675 	.func           = bpf_xdp_sk_lookup_udp,
6676 	.gpl_only       = false,
6677 	.pkt_access     = true,
6678 	.ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
6679 	.arg1_type      = ARG_PTR_TO_CTX,
6680 	.arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
6681 	.arg3_type      = ARG_CONST_SIZE,
6682 	.arg4_type      = ARG_ANYTHING,
6683 	.arg5_type      = ARG_ANYTHING,
6684 };
6685 
BPF_CALL_5(bpf_xdp_skc_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6686 BPF_CALL_5(bpf_xdp_skc_lookup_tcp, struct xdp_buff *, ctx,
6687 	   struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6688 {
6689 	struct net *caller_net = dev_net(ctx->rxq->dev);
6690 	int ifindex = ctx->rxq->dev->ifindex;
6691 
6692 	return (unsigned long)__bpf_skc_lookup(NULL, tuple, len, caller_net,
6693 					       ifindex, IPPROTO_TCP, netns_id,
6694 					       flags);
6695 }
6696 
6697 static const struct bpf_func_proto bpf_xdp_skc_lookup_tcp_proto = {
6698 	.func           = bpf_xdp_skc_lookup_tcp,
6699 	.gpl_only       = false,
6700 	.pkt_access     = true,
6701 	.ret_type       = RET_PTR_TO_SOCK_COMMON_OR_NULL,
6702 	.arg1_type      = ARG_PTR_TO_CTX,
6703 	.arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
6704 	.arg3_type      = ARG_CONST_SIZE,
6705 	.arg4_type      = ARG_ANYTHING,
6706 	.arg5_type      = ARG_ANYTHING,
6707 };
6708 
BPF_CALL_5(bpf_xdp_sk_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6709 BPF_CALL_5(bpf_xdp_sk_lookup_tcp, struct xdp_buff *, ctx,
6710 	   struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6711 {
6712 	struct net *caller_net = dev_net(ctx->rxq->dev);
6713 	int ifindex = ctx->rxq->dev->ifindex;
6714 
6715 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
6716 					      ifindex, IPPROTO_TCP, netns_id,
6717 					      flags);
6718 }
6719 
6720 static const struct bpf_func_proto bpf_xdp_sk_lookup_tcp_proto = {
6721 	.func           = bpf_xdp_sk_lookup_tcp,
6722 	.gpl_only       = false,
6723 	.pkt_access     = true,
6724 	.ret_type       = RET_PTR_TO_SOCKET_OR_NULL,
6725 	.arg1_type      = ARG_PTR_TO_CTX,
6726 	.arg2_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
6727 	.arg3_type      = ARG_CONST_SIZE,
6728 	.arg4_type      = ARG_ANYTHING,
6729 	.arg5_type      = ARG_ANYTHING,
6730 };
6731 
BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6732 BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
6733 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6734 {
6735 	return (unsigned long)__bpf_skc_lookup(NULL, tuple, len,
6736 					       sock_net(ctx->sk), 0,
6737 					       IPPROTO_TCP, netns_id, flags);
6738 }
6739 
6740 static const struct bpf_func_proto bpf_sock_addr_skc_lookup_tcp_proto = {
6741 	.func		= bpf_sock_addr_skc_lookup_tcp,
6742 	.gpl_only	= false,
6743 	.ret_type	= RET_PTR_TO_SOCK_COMMON_OR_NULL,
6744 	.arg1_type	= ARG_PTR_TO_CTX,
6745 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6746 	.arg3_type	= ARG_CONST_SIZE,
6747 	.arg4_type	= ARG_ANYTHING,
6748 	.arg5_type	= ARG_ANYTHING,
6749 };
6750 
BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6751 BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
6752 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6753 {
6754 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
6755 					      sock_net(ctx->sk), 0, IPPROTO_TCP,
6756 					      netns_id, flags);
6757 }
6758 
6759 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_tcp_proto = {
6760 	.func		= bpf_sock_addr_sk_lookup_tcp,
6761 	.gpl_only	= false,
6762 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6763 	.arg1_type	= ARG_PTR_TO_CTX,
6764 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6765 	.arg3_type	= ARG_CONST_SIZE,
6766 	.arg4_type	= ARG_ANYTHING,
6767 	.arg5_type	= ARG_ANYTHING,
6768 };
6769 
BPF_CALL_5(bpf_sock_addr_sk_lookup_udp,struct bpf_sock_addr_kern *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6770 BPF_CALL_5(bpf_sock_addr_sk_lookup_udp, struct bpf_sock_addr_kern *, ctx,
6771 	   struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6772 {
6773 	return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
6774 					      sock_net(ctx->sk), 0, IPPROTO_UDP,
6775 					      netns_id, flags);
6776 }
6777 
6778 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_udp_proto = {
6779 	.func		= bpf_sock_addr_sk_lookup_udp,
6780 	.gpl_only	= false,
6781 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6782 	.arg1_type	= ARG_PTR_TO_CTX,
6783 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
6784 	.arg3_type	= ARG_CONST_SIZE,
6785 	.arg4_type	= ARG_ANYTHING,
6786 	.arg5_type	= ARG_ANYTHING,
6787 };
6788 
bpf_tcp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)6789 bool bpf_tcp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
6790 				  struct bpf_insn_access_aux *info)
6791 {
6792 	if (off < 0 || off >= offsetofend(struct bpf_tcp_sock,
6793 					  icsk_retransmits))
6794 		return false;
6795 
6796 	if (off % size != 0)
6797 		return false;
6798 
6799 	switch (off) {
6800 	case offsetof(struct bpf_tcp_sock, bytes_received):
6801 	case offsetof(struct bpf_tcp_sock, bytes_acked):
6802 		return size == sizeof(__u64);
6803 	default:
6804 		return size == sizeof(__u32);
6805 	}
6806 }
6807 
bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)6808 u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,
6809 				    const struct bpf_insn *si,
6810 				    struct bpf_insn *insn_buf,
6811 				    struct bpf_prog *prog, u32 *target_size)
6812 {
6813 	struct bpf_insn *insn = insn_buf;
6814 
6815 #define BPF_TCP_SOCK_GET_COMMON(FIELD)					\
6816 	do {								\
6817 		BUILD_BUG_ON(sizeof_field(struct tcp_sock, FIELD) >	\
6818 			     sizeof_field(struct bpf_tcp_sock, FIELD));	\
6819 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_sock, FIELD),\
6820 				      si->dst_reg, si->src_reg,		\
6821 				      offsetof(struct tcp_sock, FIELD)); \
6822 	} while (0)
6823 
6824 #define BPF_INET_SOCK_GET_COMMON(FIELD)					\
6825 	do {								\
6826 		BUILD_BUG_ON(sizeof_field(struct inet_connection_sock,	\
6827 					  FIELD) >			\
6828 			     sizeof_field(struct bpf_tcp_sock, FIELD));	\
6829 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			\
6830 					struct inet_connection_sock,	\
6831 					FIELD),				\
6832 				      si->dst_reg, si->src_reg,		\
6833 				      offsetof(				\
6834 					struct inet_connection_sock,	\
6835 					FIELD));			\
6836 	} while (0)
6837 
6838 	if (insn > insn_buf)
6839 		return insn - insn_buf;
6840 
6841 	switch (si->off) {
6842 	case offsetof(struct bpf_tcp_sock, rtt_min):
6843 		BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
6844 			     sizeof(struct minmax));
6845 		BUILD_BUG_ON(sizeof(struct minmax) <
6846 			     sizeof(struct minmax_sample));
6847 
6848 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
6849 				      offsetof(struct tcp_sock, rtt_min) +
6850 				      offsetof(struct minmax_sample, v));
6851 		break;
6852 	case offsetof(struct bpf_tcp_sock, snd_cwnd):
6853 		BPF_TCP_SOCK_GET_COMMON(snd_cwnd);
6854 		break;
6855 	case offsetof(struct bpf_tcp_sock, srtt_us):
6856 		BPF_TCP_SOCK_GET_COMMON(srtt_us);
6857 		break;
6858 	case offsetof(struct bpf_tcp_sock, snd_ssthresh):
6859 		BPF_TCP_SOCK_GET_COMMON(snd_ssthresh);
6860 		break;
6861 	case offsetof(struct bpf_tcp_sock, rcv_nxt):
6862 		BPF_TCP_SOCK_GET_COMMON(rcv_nxt);
6863 		break;
6864 	case offsetof(struct bpf_tcp_sock, snd_nxt):
6865 		BPF_TCP_SOCK_GET_COMMON(snd_nxt);
6866 		break;
6867 	case offsetof(struct bpf_tcp_sock, snd_una):
6868 		BPF_TCP_SOCK_GET_COMMON(snd_una);
6869 		break;
6870 	case offsetof(struct bpf_tcp_sock, mss_cache):
6871 		BPF_TCP_SOCK_GET_COMMON(mss_cache);
6872 		break;
6873 	case offsetof(struct bpf_tcp_sock, ecn_flags):
6874 		BPF_TCP_SOCK_GET_COMMON(ecn_flags);
6875 		break;
6876 	case offsetof(struct bpf_tcp_sock, rate_delivered):
6877 		BPF_TCP_SOCK_GET_COMMON(rate_delivered);
6878 		break;
6879 	case offsetof(struct bpf_tcp_sock, rate_interval_us):
6880 		BPF_TCP_SOCK_GET_COMMON(rate_interval_us);
6881 		break;
6882 	case offsetof(struct bpf_tcp_sock, packets_out):
6883 		BPF_TCP_SOCK_GET_COMMON(packets_out);
6884 		break;
6885 	case offsetof(struct bpf_tcp_sock, retrans_out):
6886 		BPF_TCP_SOCK_GET_COMMON(retrans_out);
6887 		break;
6888 	case offsetof(struct bpf_tcp_sock, total_retrans):
6889 		BPF_TCP_SOCK_GET_COMMON(total_retrans);
6890 		break;
6891 	case offsetof(struct bpf_tcp_sock, segs_in):
6892 		BPF_TCP_SOCK_GET_COMMON(segs_in);
6893 		break;
6894 	case offsetof(struct bpf_tcp_sock, data_segs_in):
6895 		BPF_TCP_SOCK_GET_COMMON(data_segs_in);
6896 		break;
6897 	case offsetof(struct bpf_tcp_sock, segs_out):
6898 		BPF_TCP_SOCK_GET_COMMON(segs_out);
6899 		break;
6900 	case offsetof(struct bpf_tcp_sock, data_segs_out):
6901 		BPF_TCP_SOCK_GET_COMMON(data_segs_out);
6902 		break;
6903 	case offsetof(struct bpf_tcp_sock, lost_out):
6904 		BPF_TCP_SOCK_GET_COMMON(lost_out);
6905 		break;
6906 	case offsetof(struct bpf_tcp_sock, sacked_out):
6907 		BPF_TCP_SOCK_GET_COMMON(sacked_out);
6908 		break;
6909 	case offsetof(struct bpf_tcp_sock, bytes_received):
6910 		BPF_TCP_SOCK_GET_COMMON(bytes_received);
6911 		break;
6912 	case offsetof(struct bpf_tcp_sock, bytes_acked):
6913 		BPF_TCP_SOCK_GET_COMMON(bytes_acked);
6914 		break;
6915 	case offsetof(struct bpf_tcp_sock, dsack_dups):
6916 		BPF_TCP_SOCK_GET_COMMON(dsack_dups);
6917 		break;
6918 	case offsetof(struct bpf_tcp_sock, delivered):
6919 		BPF_TCP_SOCK_GET_COMMON(delivered);
6920 		break;
6921 	case offsetof(struct bpf_tcp_sock, delivered_ce):
6922 		BPF_TCP_SOCK_GET_COMMON(delivered_ce);
6923 		break;
6924 	case offsetof(struct bpf_tcp_sock, icsk_retransmits):
6925 		BPF_INET_SOCK_GET_COMMON(icsk_retransmits);
6926 		break;
6927 	}
6928 
6929 	return insn - insn_buf;
6930 }
6931 
BPF_CALL_1(bpf_tcp_sock,struct sock *,sk)6932 BPF_CALL_1(bpf_tcp_sock, struct sock *, sk)
6933 {
6934 	if (sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
6935 		return (unsigned long)sk;
6936 
6937 	return (unsigned long)NULL;
6938 }
6939 
6940 const struct bpf_func_proto bpf_tcp_sock_proto = {
6941 	.func		= bpf_tcp_sock,
6942 	.gpl_only	= false,
6943 	.ret_type	= RET_PTR_TO_TCP_SOCK_OR_NULL,
6944 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
6945 };
6946 
BPF_CALL_1(bpf_get_listener_sock,struct sock *,sk)6947 BPF_CALL_1(bpf_get_listener_sock, struct sock *, sk)
6948 {
6949 	sk = sk_to_full_sk(sk);
6950 
6951 	if (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_RCU_FREE))
6952 		return (unsigned long)sk;
6953 
6954 	return (unsigned long)NULL;
6955 }
6956 
6957 static const struct bpf_func_proto bpf_get_listener_sock_proto = {
6958 	.func		= bpf_get_listener_sock,
6959 	.gpl_only	= false,
6960 	.ret_type	= RET_PTR_TO_SOCKET_OR_NULL,
6961 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
6962 };
6963 
BPF_CALL_1(bpf_skb_ecn_set_ce,struct sk_buff *,skb)6964 BPF_CALL_1(bpf_skb_ecn_set_ce, struct sk_buff *, skb)
6965 {
6966 	unsigned int iphdr_len;
6967 
6968 	switch (skb_protocol(skb, true)) {
6969 	case cpu_to_be16(ETH_P_IP):
6970 		iphdr_len = sizeof(struct iphdr);
6971 		break;
6972 	case cpu_to_be16(ETH_P_IPV6):
6973 		iphdr_len = sizeof(struct ipv6hdr);
6974 		break;
6975 	default:
6976 		return 0;
6977 	}
6978 
6979 	if (skb_headlen(skb) < iphdr_len)
6980 		return 0;
6981 
6982 	if (skb_cloned(skb) && !skb_clone_writable(skb, iphdr_len))
6983 		return 0;
6984 
6985 	return INET_ECN_set_ce(skb);
6986 }
6987 
bpf_xdp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)6988 bool bpf_xdp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
6989 				  struct bpf_insn_access_aux *info)
6990 {
6991 	if (off < 0 || off >= offsetofend(struct bpf_xdp_sock, queue_id))
6992 		return false;
6993 
6994 	if (off % size != 0)
6995 		return false;
6996 
6997 	switch (off) {
6998 	default:
6999 		return size == sizeof(__u32);
7000 	}
7001 }
7002 
bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)7003 u32 bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,
7004 				    const struct bpf_insn *si,
7005 				    struct bpf_insn *insn_buf,
7006 				    struct bpf_prog *prog, u32 *target_size)
7007 {
7008 	struct bpf_insn *insn = insn_buf;
7009 
7010 #define BPF_XDP_SOCK_GET(FIELD)						\
7011 	do {								\
7012 		BUILD_BUG_ON(sizeof_field(struct xdp_sock, FIELD) >	\
7013 			     sizeof_field(struct bpf_xdp_sock, FIELD));	\
7014 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_sock, FIELD),\
7015 				      si->dst_reg, si->src_reg,		\
7016 				      offsetof(struct xdp_sock, FIELD)); \
7017 	} while (0)
7018 
7019 	switch (si->off) {
7020 	case offsetof(struct bpf_xdp_sock, queue_id):
7021 		BPF_XDP_SOCK_GET(queue_id);
7022 		break;
7023 	}
7024 
7025 	return insn - insn_buf;
7026 }
7027 
7028 static const struct bpf_func_proto bpf_skb_ecn_set_ce_proto = {
7029 	.func           = bpf_skb_ecn_set_ce,
7030 	.gpl_only       = false,
7031 	.ret_type       = RET_INTEGER,
7032 	.arg1_type      = ARG_PTR_TO_CTX,
7033 };
7034 
BPF_CALL_5(bpf_tcp_check_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)7035 BPF_CALL_5(bpf_tcp_check_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
7036 	   struct tcphdr *, th, u32, th_len)
7037 {
7038 #ifdef CONFIG_SYN_COOKIES
7039 	u32 cookie;
7040 	int ret;
7041 
7042 	if (unlikely(!sk || th_len < sizeof(*th)))
7043 		return -EINVAL;
7044 
7045 	/* sk_listener() allows TCP_NEW_SYN_RECV, which makes no sense here. */
7046 	if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
7047 		return -EINVAL;
7048 
7049 	if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
7050 		return -EINVAL;
7051 
7052 	if (!th->ack || th->rst || th->syn)
7053 		return -ENOENT;
7054 
7055 	if (unlikely(iph_len < sizeof(struct iphdr)))
7056 		return -EINVAL;
7057 
7058 	if (tcp_synq_no_recent_overflow(sk))
7059 		return -ENOENT;
7060 
7061 	cookie = ntohl(th->ack_seq) - 1;
7062 
7063 	/* Both struct iphdr and struct ipv6hdr have the version field at the
7064 	 * same offset so we can cast to the shorter header (struct iphdr).
7065 	 */
7066 	switch (((struct iphdr *)iph)->version) {
7067 	case 4:
7068 		if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
7069 			return -EINVAL;
7070 
7071 		ret = __cookie_v4_check((struct iphdr *)iph, th, cookie);
7072 		break;
7073 
7074 #if IS_BUILTIN(CONFIG_IPV6)
7075 	case 6:
7076 		if (unlikely(iph_len < sizeof(struct ipv6hdr)))
7077 			return -EINVAL;
7078 
7079 		if (sk->sk_family != AF_INET6)
7080 			return -EINVAL;
7081 
7082 		ret = __cookie_v6_check((struct ipv6hdr *)iph, th, cookie);
7083 		break;
7084 #endif /* CONFIG_IPV6 */
7085 
7086 	default:
7087 		return -EPROTONOSUPPORT;
7088 	}
7089 
7090 	if (ret > 0)
7091 		return 0;
7092 
7093 	return -ENOENT;
7094 #else
7095 	return -ENOTSUPP;
7096 #endif
7097 }
7098 
7099 static const struct bpf_func_proto bpf_tcp_check_syncookie_proto = {
7100 	.func		= bpf_tcp_check_syncookie,
7101 	.gpl_only	= true,
7102 	.pkt_access	= true,
7103 	.ret_type	= RET_INTEGER,
7104 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7105 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7106 	.arg3_type	= ARG_CONST_SIZE,
7107 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7108 	.arg5_type	= ARG_CONST_SIZE,
7109 };
7110 
BPF_CALL_5(bpf_tcp_gen_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)7111 BPF_CALL_5(bpf_tcp_gen_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
7112 	   struct tcphdr *, th, u32, th_len)
7113 {
7114 #ifdef CONFIG_SYN_COOKIES
7115 	u32 cookie;
7116 	u16 mss;
7117 
7118 	if (unlikely(!sk || th_len < sizeof(*th) || th_len != th->doff * 4))
7119 		return -EINVAL;
7120 
7121 	if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
7122 		return -EINVAL;
7123 
7124 	if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
7125 		return -ENOENT;
7126 
7127 	if (!th->syn || th->ack || th->fin || th->rst)
7128 		return -EINVAL;
7129 
7130 	if (unlikely(iph_len < sizeof(struct iphdr)))
7131 		return -EINVAL;
7132 
7133 	/* Both struct iphdr and struct ipv6hdr have the version field at the
7134 	 * same offset so we can cast to the shorter header (struct iphdr).
7135 	 */
7136 	switch (((struct iphdr *)iph)->version) {
7137 	case 4:
7138 		if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
7139 			return -EINVAL;
7140 
7141 		mss = tcp_v4_get_syncookie(sk, iph, th, &cookie);
7142 		break;
7143 
7144 #if IS_BUILTIN(CONFIG_IPV6)
7145 	case 6:
7146 		if (unlikely(iph_len < sizeof(struct ipv6hdr)))
7147 			return -EINVAL;
7148 
7149 		if (sk->sk_family != AF_INET6)
7150 			return -EINVAL;
7151 
7152 		mss = tcp_v6_get_syncookie(sk, iph, th, &cookie);
7153 		break;
7154 #endif /* CONFIG_IPV6 */
7155 
7156 	default:
7157 		return -EPROTONOSUPPORT;
7158 	}
7159 	if (mss == 0)
7160 		return -ENOENT;
7161 
7162 	return cookie | ((u64)mss << 32);
7163 #else
7164 	return -EOPNOTSUPP;
7165 #endif /* CONFIG_SYN_COOKIES */
7166 }
7167 
7168 static const struct bpf_func_proto bpf_tcp_gen_syncookie_proto = {
7169 	.func		= bpf_tcp_gen_syncookie,
7170 	.gpl_only	= true, /* __cookie_v*_init_sequence() is GPL */
7171 	.pkt_access	= true,
7172 	.ret_type	= RET_INTEGER,
7173 	.arg1_type	= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7174 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7175 	.arg3_type	= ARG_CONST_SIZE,
7176 	.arg4_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7177 	.arg5_type	= ARG_CONST_SIZE,
7178 };
7179 
BPF_CALL_3(bpf_sk_assign,struct sk_buff *,skb,struct sock *,sk,u64,flags)7180 BPF_CALL_3(bpf_sk_assign, struct sk_buff *, skb, struct sock *, sk, u64, flags)
7181 {
7182 	if (!sk || flags != 0)
7183 		return -EINVAL;
7184 	if (!skb_at_tc_ingress(skb))
7185 		return -EOPNOTSUPP;
7186 	if (unlikely(dev_net(skb->dev) != sock_net(sk)))
7187 		return -ENETUNREACH;
7188 	if (unlikely(sk_fullsock(sk) && sk->sk_reuseport))
7189 		return -ESOCKTNOSUPPORT;
7190 	if (sk_is_refcounted(sk) &&
7191 	    unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
7192 		return -ENOENT;
7193 
7194 	skb_orphan(skb);
7195 	skb->sk = sk;
7196 	skb->destructor = sock_pfree;
7197 
7198 	return 0;
7199 }
7200 
7201 static const struct bpf_func_proto bpf_sk_assign_proto = {
7202 	.func		= bpf_sk_assign,
7203 	.gpl_only	= false,
7204 	.ret_type	= RET_INTEGER,
7205 	.arg1_type      = ARG_PTR_TO_CTX,
7206 	.arg2_type      = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7207 	.arg3_type	= ARG_ANYTHING,
7208 };
7209 
bpf_search_tcp_opt(const u8 * op,const u8 * opend,u8 search_kind,const u8 * magic,u8 magic_len,bool * eol)7210 static const u8 *bpf_search_tcp_opt(const u8 *op, const u8 *opend,
7211 				    u8 search_kind, const u8 *magic,
7212 				    u8 magic_len, bool *eol)
7213 {
7214 	u8 kind, kind_len;
7215 
7216 	*eol = false;
7217 
7218 	while (op < opend) {
7219 		kind = op[0];
7220 
7221 		if (kind == TCPOPT_EOL) {
7222 			*eol = true;
7223 			return ERR_PTR(-ENOMSG);
7224 		} else if (kind == TCPOPT_NOP) {
7225 			op++;
7226 			continue;
7227 		}
7228 
7229 		if (opend - op < 2 || opend - op < op[1] || op[1] < 2)
7230 			/* Something is wrong in the received header.
7231 			 * Follow the TCP stack's tcp_parse_options()
7232 			 * and just bail here.
7233 			 */
7234 			return ERR_PTR(-EFAULT);
7235 
7236 		kind_len = op[1];
7237 		if (search_kind == kind) {
7238 			if (!magic_len)
7239 				return op;
7240 
7241 			if (magic_len > kind_len - 2)
7242 				return ERR_PTR(-ENOMSG);
7243 
7244 			if (!memcmp(&op[2], magic, magic_len))
7245 				return op;
7246 		}
7247 
7248 		op += kind_len;
7249 	}
7250 
7251 	return ERR_PTR(-ENOMSG);
7252 }
7253 
BPF_CALL_4(bpf_sock_ops_load_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,void *,search_res,u32,len,u64,flags)7254 BPF_CALL_4(bpf_sock_ops_load_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7255 	   void *, search_res, u32, len, u64, flags)
7256 {
7257 	bool eol, load_syn = flags & BPF_LOAD_HDR_OPT_TCP_SYN;
7258 	const u8 *op, *opend, *magic, *search = search_res;
7259 	u8 search_kind, search_len, copy_len, magic_len;
7260 	int ret;
7261 
7262 	/* 2 byte is the minimal option len except TCPOPT_NOP and
7263 	 * TCPOPT_EOL which are useless for the bpf prog to learn
7264 	 * and this helper disallow loading them also.
7265 	 */
7266 	if (len < 2 || flags & ~BPF_LOAD_HDR_OPT_TCP_SYN)
7267 		return -EINVAL;
7268 
7269 	search_kind = search[0];
7270 	search_len = search[1];
7271 
7272 	if (search_len > len || search_kind == TCPOPT_NOP ||
7273 	    search_kind == TCPOPT_EOL)
7274 		return -EINVAL;
7275 
7276 	if (search_kind == TCPOPT_EXP || search_kind == 253) {
7277 		/* 16 or 32 bit magic.  +2 for kind and kind length */
7278 		if (search_len != 4 && search_len != 6)
7279 			return -EINVAL;
7280 		magic = &search[2];
7281 		magic_len = search_len - 2;
7282 	} else {
7283 		if (search_len)
7284 			return -EINVAL;
7285 		magic = NULL;
7286 		magic_len = 0;
7287 	}
7288 
7289 	if (load_syn) {
7290 		ret = bpf_sock_ops_get_syn(bpf_sock, TCP_BPF_SYN, &op);
7291 		if (ret < 0)
7292 			return ret;
7293 
7294 		opend = op + ret;
7295 		op += sizeof(struct tcphdr);
7296 	} else {
7297 		if (!bpf_sock->skb ||
7298 		    bpf_sock->op == BPF_SOCK_OPS_HDR_OPT_LEN_CB)
7299 			/* This bpf_sock->op cannot call this helper */
7300 			return -EPERM;
7301 
7302 		opend = bpf_sock->skb_data_end;
7303 		op = bpf_sock->skb->data + sizeof(struct tcphdr);
7304 	}
7305 
7306 	op = bpf_search_tcp_opt(op, opend, search_kind, magic, magic_len,
7307 				&eol);
7308 	if (IS_ERR(op))
7309 		return PTR_ERR(op);
7310 
7311 	copy_len = op[1];
7312 	ret = copy_len;
7313 	if (copy_len > len) {
7314 		ret = -ENOSPC;
7315 		copy_len = len;
7316 	}
7317 
7318 	memcpy(search_res, op, copy_len);
7319 	return ret;
7320 }
7321 
7322 static const struct bpf_func_proto bpf_sock_ops_load_hdr_opt_proto = {
7323 	.func		= bpf_sock_ops_load_hdr_opt,
7324 	.gpl_only	= false,
7325 	.ret_type	= RET_INTEGER,
7326 	.arg1_type	= ARG_PTR_TO_CTX,
7327 	.arg2_type	= ARG_PTR_TO_MEM,
7328 	.arg3_type	= ARG_CONST_SIZE,
7329 	.arg4_type	= ARG_ANYTHING,
7330 };
7331 
BPF_CALL_4(bpf_sock_ops_store_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,const void *,from,u32,len,u64,flags)7332 BPF_CALL_4(bpf_sock_ops_store_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7333 	   const void *, from, u32, len, u64, flags)
7334 {
7335 	u8 new_kind, new_kind_len, magic_len = 0, *opend;
7336 	const u8 *op, *new_op, *magic = NULL;
7337 	struct sk_buff *skb;
7338 	bool eol;
7339 
7340 	if (bpf_sock->op != BPF_SOCK_OPS_WRITE_HDR_OPT_CB)
7341 		return -EPERM;
7342 
7343 	if (len < 2 || flags)
7344 		return -EINVAL;
7345 
7346 	new_op = from;
7347 	new_kind = new_op[0];
7348 	new_kind_len = new_op[1];
7349 
7350 	if (new_kind_len > len || new_kind == TCPOPT_NOP ||
7351 	    new_kind == TCPOPT_EOL)
7352 		return -EINVAL;
7353 
7354 	if (new_kind_len > bpf_sock->remaining_opt_len)
7355 		return -ENOSPC;
7356 
7357 	/* 253 is another experimental kind */
7358 	if (new_kind == TCPOPT_EXP || new_kind == 253)  {
7359 		if (new_kind_len < 4)
7360 			return -EINVAL;
7361 		/* Match for the 2 byte magic also.
7362 		 * RFC 6994: the magic could be 2 or 4 bytes.
7363 		 * Hence, matching by 2 byte only is on the
7364 		 * conservative side but it is the right
7365 		 * thing to do for the 'search-for-duplication'
7366 		 * purpose.
7367 		 */
7368 		magic = &new_op[2];
7369 		magic_len = 2;
7370 	}
7371 
7372 	/* Check for duplication */
7373 	skb = bpf_sock->skb;
7374 	op = skb->data + sizeof(struct tcphdr);
7375 	opend = bpf_sock->skb_data_end;
7376 
7377 	op = bpf_search_tcp_opt(op, opend, new_kind, magic, magic_len,
7378 				&eol);
7379 	if (!IS_ERR(op))
7380 		return -EEXIST;
7381 
7382 	if (PTR_ERR(op) != -ENOMSG)
7383 		return PTR_ERR(op);
7384 
7385 	if (eol)
7386 		/* The option has been ended.  Treat it as no more
7387 		 * header option can be written.
7388 		 */
7389 		return -ENOSPC;
7390 
7391 	/* No duplication found.  Store the header option. */
7392 	memcpy(opend, from, new_kind_len);
7393 
7394 	bpf_sock->remaining_opt_len -= new_kind_len;
7395 	bpf_sock->skb_data_end += new_kind_len;
7396 
7397 	return 0;
7398 }
7399 
7400 static const struct bpf_func_proto bpf_sock_ops_store_hdr_opt_proto = {
7401 	.func		= bpf_sock_ops_store_hdr_opt,
7402 	.gpl_only	= false,
7403 	.ret_type	= RET_INTEGER,
7404 	.arg1_type	= ARG_PTR_TO_CTX,
7405 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
7406 	.arg3_type	= ARG_CONST_SIZE,
7407 	.arg4_type	= ARG_ANYTHING,
7408 };
7409 
BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,u32,len,u64,flags)7410 BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7411 	   u32, len, u64, flags)
7412 {
7413 	if (bpf_sock->op != BPF_SOCK_OPS_HDR_OPT_LEN_CB)
7414 		return -EPERM;
7415 
7416 	if (flags || len < 2)
7417 		return -EINVAL;
7418 
7419 	if (len > bpf_sock->remaining_opt_len)
7420 		return -ENOSPC;
7421 
7422 	bpf_sock->remaining_opt_len -= len;
7423 
7424 	return 0;
7425 }
7426 
7427 static const struct bpf_func_proto bpf_sock_ops_reserve_hdr_opt_proto = {
7428 	.func		= bpf_sock_ops_reserve_hdr_opt,
7429 	.gpl_only	= false,
7430 	.ret_type	= RET_INTEGER,
7431 	.arg1_type	= ARG_PTR_TO_CTX,
7432 	.arg2_type	= ARG_ANYTHING,
7433 	.arg3_type	= ARG_ANYTHING,
7434 };
7435 
BPF_CALL_3(bpf_skb_set_tstamp,struct sk_buff *,skb,u64,tstamp,u32,tstamp_type)7436 BPF_CALL_3(bpf_skb_set_tstamp, struct sk_buff *, skb,
7437 	   u64, tstamp, u32, tstamp_type)
7438 {
7439 	/* skb_clear_delivery_time() is done for inet protocol */
7440 	if (skb->protocol != htons(ETH_P_IP) &&
7441 	    skb->protocol != htons(ETH_P_IPV6))
7442 		return -EOPNOTSUPP;
7443 
7444 	switch (tstamp_type) {
7445 	case BPF_SKB_TSTAMP_DELIVERY_MONO:
7446 		if (!tstamp)
7447 			return -EINVAL;
7448 		skb->tstamp = tstamp;
7449 		skb->mono_delivery_time = 1;
7450 		break;
7451 	case BPF_SKB_TSTAMP_UNSPEC:
7452 		if (tstamp)
7453 			return -EINVAL;
7454 		skb->tstamp = 0;
7455 		skb->mono_delivery_time = 0;
7456 		break;
7457 	default:
7458 		return -EINVAL;
7459 	}
7460 
7461 	return 0;
7462 }
7463 
7464 static const struct bpf_func_proto bpf_skb_set_tstamp_proto = {
7465 	.func           = bpf_skb_set_tstamp,
7466 	.gpl_only       = false,
7467 	.ret_type       = RET_INTEGER,
7468 	.arg1_type      = ARG_PTR_TO_CTX,
7469 	.arg2_type      = ARG_ANYTHING,
7470 	.arg3_type      = ARG_ANYTHING,
7471 };
7472 
7473 #ifdef CONFIG_SYN_COOKIES
BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv4,struct iphdr *,iph,struct tcphdr *,th,u32,th_len)7474 BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv4, struct iphdr *, iph,
7475 	   struct tcphdr *, th, u32, th_len)
7476 {
7477 	u32 cookie;
7478 	u16 mss;
7479 
7480 	if (unlikely(th_len < sizeof(*th) || th_len != th->doff * 4))
7481 		return -EINVAL;
7482 
7483 	mss = tcp_parse_mss_option(th, 0) ?: TCP_MSS_DEFAULT;
7484 	cookie = __cookie_v4_init_sequence(iph, th, &mss);
7485 
7486 	return cookie | ((u64)mss << 32);
7487 }
7488 
7489 static const struct bpf_func_proto bpf_tcp_raw_gen_syncookie_ipv4_proto = {
7490 	.func		= bpf_tcp_raw_gen_syncookie_ipv4,
7491 	.gpl_only	= true, /* __cookie_v4_init_sequence() is GPL */
7492 	.pkt_access	= true,
7493 	.ret_type	= RET_INTEGER,
7494 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7495 	.arg1_size	= sizeof(struct iphdr),
7496 	.arg2_type	= ARG_PTR_TO_MEM,
7497 	.arg3_type	= ARG_CONST_SIZE,
7498 };
7499 
BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv6,struct ipv6hdr *,iph,struct tcphdr *,th,u32,th_len)7500 BPF_CALL_3(bpf_tcp_raw_gen_syncookie_ipv6, struct ipv6hdr *, iph,
7501 	   struct tcphdr *, th, u32, th_len)
7502 {
7503 #if IS_BUILTIN(CONFIG_IPV6)
7504 	const u16 mss_clamp = IPV6_MIN_MTU - sizeof(struct tcphdr) -
7505 		sizeof(struct ipv6hdr);
7506 	u32 cookie;
7507 	u16 mss;
7508 
7509 	if (unlikely(th_len < sizeof(*th) || th_len != th->doff * 4))
7510 		return -EINVAL;
7511 
7512 	mss = tcp_parse_mss_option(th, 0) ?: mss_clamp;
7513 	cookie = __cookie_v6_init_sequence(iph, th, &mss);
7514 
7515 	return cookie | ((u64)mss << 32);
7516 #else
7517 	return -EPROTONOSUPPORT;
7518 #endif
7519 }
7520 
7521 static const struct bpf_func_proto bpf_tcp_raw_gen_syncookie_ipv6_proto = {
7522 	.func		= bpf_tcp_raw_gen_syncookie_ipv6,
7523 	.gpl_only	= true, /* __cookie_v6_init_sequence() is GPL */
7524 	.pkt_access	= true,
7525 	.ret_type	= RET_INTEGER,
7526 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7527 	.arg1_size	= sizeof(struct ipv6hdr),
7528 	.arg2_type	= ARG_PTR_TO_MEM,
7529 	.arg3_type	= ARG_CONST_SIZE,
7530 };
7531 
BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv4,struct iphdr *,iph,struct tcphdr *,th)7532 BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv4, struct iphdr *, iph,
7533 	   struct tcphdr *, th)
7534 {
7535 	u32 cookie = ntohl(th->ack_seq) - 1;
7536 
7537 	if (__cookie_v4_check(iph, th, cookie) > 0)
7538 		return 0;
7539 
7540 	return -EACCES;
7541 }
7542 
7543 static const struct bpf_func_proto bpf_tcp_raw_check_syncookie_ipv4_proto = {
7544 	.func		= bpf_tcp_raw_check_syncookie_ipv4,
7545 	.gpl_only	= true, /* __cookie_v4_check is GPL */
7546 	.pkt_access	= true,
7547 	.ret_type	= RET_INTEGER,
7548 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7549 	.arg1_size	= sizeof(struct iphdr),
7550 	.arg2_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7551 	.arg2_size	= sizeof(struct tcphdr),
7552 };
7553 
BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv6,struct ipv6hdr *,iph,struct tcphdr *,th)7554 BPF_CALL_2(bpf_tcp_raw_check_syncookie_ipv6, struct ipv6hdr *, iph,
7555 	   struct tcphdr *, th)
7556 {
7557 #if IS_BUILTIN(CONFIG_IPV6)
7558 	u32 cookie = ntohl(th->ack_seq) - 1;
7559 
7560 	if (__cookie_v6_check(iph, th, cookie) > 0)
7561 		return 0;
7562 
7563 	return -EACCES;
7564 #else
7565 	return -EPROTONOSUPPORT;
7566 #endif
7567 }
7568 
7569 static const struct bpf_func_proto bpf_tcp_raw_check_syncookie_ipv6_proto = {
7570 	.func		= bpf_tcp_raw_check_syncookie_ipv6,
7571 	.gpl_only	= true, /* __cookie_v6_check is GPL */
7572 	.pkt_access	= true,
7573 	.ret_type	= RET_INTEGER,
7574 	.arg1_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7575 	.arg1_size	= sizeof(struct ipv6hdr),
7576 	.arg2_type	= ARG_PTR_TO_FIXED_SIZE_MEM,
7577 	.arg2_size	= sizeof(struct tcphdr),
7578 };
7579 #endif /* CONFIG_SYN_COOKIES */
7580 
7581 #endif /* CONFIG_INET */
7582 
bpf_helper_changes_pkt_data(void * func)7583 bool bpf_helper_changes_pkt_data(void *func)
7584 {
7585 	if (func == bpf_skb_vlan_push ||
7586 	    func == bpf_skb_vlan_pop ||
7587 	    func == bpf_skb_store_bytes ||
7588 	    func == bpf_skb_change_proto ||
7589 	    func == bpf_skb_change_head ||
7590 	    func == sk_skb_change_head ||
7591 	    func == bpf_skb_change_tail ||
7592 	    func == sk_skb_change_tail ||
7593 	    func == bpf_skb_adjust_room ||
7594 	    func == sk_skb_adjust_room ||
7595 	    func == bpf_skb_pull_data ||
7596 	    func == sk_skb_pull_data ||
7597 	    func == bpf_clone_redirect ||
7598 	    func == bpf_l3_csum_replace ||
7599 	    func == bpf_l4_csum_replace ||
7600 	    func == bpf_xdp_adjust_head ||
7601 	    func == bpf_xdp_adjust_meta ||
7602 	    func == bpf_msg_pull_data ||
7603 	    func == bpf_msg_push_data ||
7604 	    func == bpf_msg_pop_data ||
7605 	    func == bpf_xdp_adjust_tail ||
7606 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
7607 	    func == bpf_lwt_seg6_store_bytes ||
7608 	    func == bpf_lwt_seg6_adjust_srh ||
7609 	    func == bpf_lwt_seg6_action ||
7610 #endif
7611 #ifdef CONFIG_INET
7612 	    func == bpf_sock_ops_store_hdr_opt ||
7613 #endif
7614 	    func == bpf_lwt_in_push_encap ||
7615 	    func == bpf_lwt_xmit_push_encap)
7616 		return true;
7617 
7618 	return false;
7619 }
7620 
7621 const struct bpf_func_proto bpf_event_output_data_proto __weak;
7622 const struct bpf_func_proto bpf_sk_storage_get_cg_sock_proto __weak;
7623 
7624 static const struct bpf_func_proto *
sock_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7625 sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7626 {
7627 	const struct bpf_func_proto *func_proto;
7628 
7629 	func_proto = cgroup_common_func_proto(func_id, prog);
7630 	if (func_proto)
7631 		return func_proto;
7632 
7633 	func_proto = cgroup_current_func_proto(func_id, prog);
7634 	if (func_proto)
7635 		return func_proto;
7636 
7637 	switch (func_id) {
7638 	case BPF_FUNC_get_socket_cookie:
7639 		return &bpf_get_socket_cookie_sock_proto;
7640 	case BPF_FUNC_get_netns_cookie:
7641 		return &bpf_get_netns_cookie_sock_proto;
7642 	case BPF_FUNC_perf_event_output:
7643 		return &bpf_event_output_data_proto;
7644 	case BPF_FUNC_sk_storage_get:
7645 		return &bpf_sk_storage_get_cg_sock_proto;
7646 	case BPF_FUNC_ktime_get_coarse_ns:
7647 		return &bpf_ktime_get_coarse_ns_proto;
7648 	default:
7649 		return bpf_base_func_proto(func_id);
7650 	}
7651 }
7652 
7653 static const struct bpf_func_proto *
sock_addr_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7654 sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7655 {
7656 	const struct bpf_func_proto *func_proto;
7657 
7658 	func_proto = cgroup_common_func_proto(func_id, prog);
7659 	if (func_proto)
7660 		return func_proto;
7661 
7662 	func_proto = cgroup_current_func_proto(func_id, prog);
7663 	if (func_proto)
7664 		return func_proto;
7665 
7666 	switch (func_id) {
7667 	case BPF_FUNC_bind:
7668 		switch (prog->expected_attach_type) {
7669 		case BPF_CGROUP_INET4_CONNECT:
7670 		case BPF_CGROUP_INET6_CONNECT:
7671 			return &bpf_bind_proto;
7672 		default:
7673 			return NULL;
7674 		}
7675 	case BPF_FUNC_get_socket_cookie:
7676 		return &bpf_get_socket_cookie_sock_addr_proto;
7677 	case BPF_FUNC_get_netns_cookie:
7678 		return &bpf_get_netns_cookie_sock_addr_proto;
7679 	case BPF_FUNC_perf_event_output:
7680 		return &bpf_event_output_data_proto;
7681 #ifdef CONFIG_INET
7682 	case BPF_FUNC_sk_lookup_tcp:
7683 		return &bpf_sock_addr_sk_lookup_tcp_proto;
7684 	case BPF_FUNC_sk_lookup_udp:
7685 		return &bpf_sock_addr_sk_lookup_udp_proto;
7686 	case BPF_FUNC_sk_release:
7687 		return &bpf_sk_release_proto;
7688 	case BPF_FUNC_skc_lookup_tcp:
7689 		return &bpf_sock_addr_skc_lookup_tcp_proto;
7690 #endif /* CONFIG_INET */
7691 	case BPF_FUNC_sk_storage_get:
7692 		return &bpf_sk_storage_get_proto;
7693 	case BPF_FUNC_sk_storage_delete:
7694 		return &bpf_sk_storage_delete_proto;
7695 	case BPF_FUNC_setsockopt:
7696 		switch (prog->expected_attach_type) {
7697 		case BPF_CGROUP_INET4_BIND:
7698 		case BPF_CGROUP_INET6_BIND:
7699 		case BPF_CGROUP_INET4_CONNECT:
7700 		case BPF_CGROUP_INET6_CONNECT:
7701 		case BPF_CGROUP_UDP4_RECVMSG:
7702 		case BPF_CGROUP_UDP6_RECVMSG:
7703 		case BPF_CGROUP_UDP4_SENDMSG:
7704 		case BPF_CGROUP_UDP6_SENDMSG:
7705 		case BPF_CGROUP_INET4_GETPEERNAME:
7706 		case BPF_CGROUP_INET6_GETPEERNAME:
7707 		case BPF_CGROUP_INET4_GETSOCKNAME:
7708 		case BPF_CGROUP_INET6_GETSOCKNAME:
7709 			return &bpf_sock_addr_setsockopt_proto;
7710 		default:
7711 			return NULL;
7712 		}
7713 	case BPF_FUNC_getsockopt:
7714 		switch (prog->expected_attach_type) {
7715 		case BPF_CGROUP_INET4_BIND:
7716 		case BPF_CGROUP_INET6_BIND:
7717 		case BPF_CGROUP_INET4_CONNECT:
7718 		case BPF_CGROUP_INET6_CONNECT:
7719 		case BPF_CGROUP_UDP4_RECVMSG:
7720 		case BPF_CGROUP_UDP6_RECVMSG:
7721 		case BPF_CGROUP_UDP4_SENDMSG:
7722 		case BPF_CGROUP_UDP6_SENDMSG:
7723 		case BPF_CGROUP_INET4_GETPEERNAME:
7724 		case BPF_CGROUP_INET6_GETPEERNAME:
7725 		case BPF_CGROUP_INET4_GETSOCKNAME:
7726 		case BPF_CGROUP_INET6_GETSOCKNAME:
7727 			return &bpf_sock_addr_getsockopt_proto;
7728 		default:
7729 			return NULL;
7730 		}
7731 	default:
7732 		return bpf_sk_base_func_proto(func_id);
7733 	}
7734 }
7735 
7736 static const struct bpf_func_proto *
sk_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7737 sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7738 {
7739 	switch (func_id) {
7740 	case BPF_FUNC_skb_load_bytes:
7741 		return &bpf_skb_load_bytes_proto;
7742 	case BPF_FUNC_skb_load_bytes_relative:
7743 		return &bpf_skb_load_bytes_relative_proto;
7744 	case BPF_FUNC_get_socket_cookie:
7745 		return &bpf_get_socket_cookie_proto;
7746 	case BPF_FUNC_get_socket_uid:
7747 		return &bpf_get_socket_uid_proto;
7748 	case BPF_FUNC_perf_event_output:
7749 		return &bpf_skb_event_output_proto;
7750 	default:
7751 		return bpf_sk_base_func_proto(func_id);
7752 	}
7753 }
7754 
7755 const struct bpf_func_proto bpf_sk_storage_get_proto __weak;
7756 const struct bpf_func_proto bpf_sk_storage_delete_proto __weak;
7757 
7758 static const struct bpf_func_proto *
cg_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7759 cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7760 {
7761 	const struct bpf_func_proto *func_proto;
7762 
7763 	func_proto = cgroup_common_func_proto(func_id, prog);
7764 	if (func_proto)
7765 		return func_proto;
7766 
7767 	switch (func_id) {
7768 	case BPF_FUNC_sk_fullsock:
7769 		return &bpf_sk_fullsock_proto;
7770 	case BPF_FUNC_sk_storage_get:
7771 		return &bpf_sk_storage_get_proto;
7772 	case BPF_FUNC_sk_storage_delete:
7773 		return &bpf_sk_storage_delete_proto;
7774 	case BPF_FUNC_perf_event_output:
7775 		return &bpf_skb_event_output_proto;
7776 #ifdef CONFIG_SOCK_CGROUP_DATA
7777 	case BPF_FUNC_skb_cgroup_id:
7778 		return &bpf_skb_cgroup_id_proto;
7779 	case BPF_FUNC_skb_ancestor_cgroup_id:
7780 		return &bpf_skb_ancestor_cgroup_id_proto;
7781 	case BPF_FUNC_sk_cgroup_id:
7782 		return &bpf_sk_cgroup_id_proto;
7783 	case BPF_FUNC_sk_ancestor_cgroup_id:
7784 		return &bpf_sk_ancestor_cgroup_id_proto;
7785 #endif
7786 #ifdef CONFIG_INET
7787 	case BPF_FUNC_sk_lookup_tcp:
7788 		return &bpf_sk_lookup_tcp_proto;
7789 	case BPF_FUNC_sk_lookup_udp:
7790 		return &bpf_sk_lookup_udp_proto;
7791 	case BPF_FUNC_sk_release:
7792 		return &bpf_sk_release_proto;
7793 	case BPF_FUNC_skc_lookup_tcp:
7794 		return &bpf_skc_lookup_tcp_proto;
7795 	case BPF_FUNC_tcp_sock:
7796 		return &bpf_tcp_sock_proto;
7797 	case BPF_FUNC_get_listener_sock:
7798 		return &bpf_get_listener_sock_proto;
7799 	case BPF_FUNC_skb_ecn_set_ce:
7800 		return &bpf_skb_ecn_set_ce_proto;
7801 #endif
7802 	default:
7803 		return sk_filter_func_proto(func_id, prog);
7804 	}
7805 }
7806 
7807 static const struct bpf_func_proto *
tc_cls_act_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7808 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7809 {
7810 	switch (func_id) {
7811 	case BPF_FUNC_skb_store_bytes:
7812 		return &bpf_skb_store_bytes_proto;
7813 	case BPF_FUNC_skb_load_bytes:
7814 		return &bpf_skb_load_bytes_proto;
7815 	case BPF_FUNC_skb_load_bytes_relative:
7816 		return &bpf_skb_load_bytes_relative_proto;
7817 	case BPF_FUNC_skb_pull_data:
7818 		return &bpf_skb_pull_data_proto;
7819 	case BPF_FUNC_csum_diff:
7820 		return &bpf_csum_diff_proto;
7821 	case BPF_FUNC_csum_update:
7822 		return &bpf_csum_update_proto;
7823 	case BPF_FUNC_csum_level:
7824 		return &bpf_csum_level_proto;
7825 	case BPF_FUNC_l3_csum_replace:
7826 		return &bpf_l3_csum_replace_proto;
7827 	case BPF_FUNC_l4_csum_replace:
7828 		return &bpf_l4_csum_replace_proto;
7829 	case BPF_FUNC_clone_redirect:
7830 		return &bpf_clone_redirect_proto;
7831 	case BPF_FUNC_get_cgroup_classid:
7832 		return &bpf_get_cgroup_classid_proto;
7833 	case BPF_FUNC_skb_vlan_push:
7834 		return &bpf_skb_vlan_push_proto;
7835 	case BPF_FUNC_skb_vlan_pop:
7836 		return &bpf_skb_vlan_pop_proto;
7837 	case BPF_FUNC_skb_change_proto:
7838 		return &bpf_skb_change_proto_proto;
7839 	case BPF_FUNC_skb_change_type:
7840 		return &bpf_skb_change_type_proto;
7841 	case BPF_FUNC_skb_adjust_room:
7842 		return &bpf_skb_adjust_room_proto;
7843 	case BPF_FUNC_skb_change_tail:
7844 		return &bpf_skb_change_tail_proto;
7845 	case BPF_FUNC_skb_change_head:
7846 		return &bpf_skb_change_head_proto;
7847 	case BPF_FUNC_skb_get_tunnel_key:
7848 		return &bpf_skb_get_tunnel_key_proto;
7849 	case BPF_FUNC_skb_set_tunnel_key:
7850 		return bpf_get_skb_set_tunnel_proto(func_id);
7851 	case BPF_FUNC_skb_get_tunnel_opt:
7852 		return &bpf_skb_get_tunnel_opt_proto;
7853 	case BPF_FUNC_skb_set_tunnel_opt:
7854 		return bpf_get_skb_set_tunnel_proto(func_id);
7855 	case BPF_FUNC_redirect:
7856 		return &bpf_redirect_proto;
7857 	case BPF_FUNC_redirect_neigh:
7858 		return &bpf_redirect_neigh_proto;
7859 	case BPF_FUNC_redirect_peer:
7860 		return &bpf_redirect_peer_proto;
7861 	case BPF_FUNC_get_route_realm:
7862 		return &bpf_get_route_realm_proto;
7863 	case BPF_FUNC_get_hash_recalc:
7864 		return &bpf_get_hash_recalc_proto;
7865 	case BPF_FUNC_set_hash_invalid:
7866 		return &bpf_set_hash_invalid_proto;
7867 	case BPF_FUNC_set_hash:
7868 		return &bpf_set_hash_proto;
7869 	case BPF_FUNC_perf_event_output:
7870 		return &bpf_skb_event_output_proto;
7871 	case BPF_FUNC_get_smp_processor_id:
7872 		return &bpf_get_smp_processor_id_proto;
7873 	case BPF_FUNC_skb_under_cgroup:
7874 		return &bpf_skb_under_cgroup_proto;
7875 	case BPF_FUNC_get_socket_cookie:
7876 		return &bpf_get_socket_cookie_proto;
7877 	case BPF_FUNC_get_socket_uid:
7878 		return &bpf_get_socket_uid_proto;
7879 	case BPF_FUNC_fib_lookup:
7880 		return &bpf_skb_fib_lookup_proto;
7881 	case BPF_FUNC_check_mtu:
7882 		return &bpf_skb_check_mtu_proto;
7883 	case BPF_FUNC_sk_fullsock:
7884 		return &bpf_sk_fullsock_proto;
7885 	case BPF_FUNC_sk_storage_get:
7886 		return &bpf_sk_storage_get_proto;
7887 	case BPF_FUNC_sk_storage_delete:
7888 		return &bpf_sk_storage_delete_proto;
7889 #ifdef CONFIG_XFRM
7890 	case BPF_FUNC_skb_get_xfrm_state:
7891 		return &bpf_skb_get_xfrm_state_proto;
7892 #endif
7893 #ifdef CONFIG_CGROUP_NET_CLASSID
7894 	case BPF_FUNC_skb_cgroup_classid:
7895 		return &bpf_skb_cgroup_classid_proto;
7896 #endif
7897 #ifdef CONFIG_SOCK_CGROUP_DATA
7898 	case BPF_FUNC_skb_cgroup_id:
7899 		return &bpf_skb_cgroup_id_proto;
7900 	case BPF_FUNC_skb_ancestor_cgroup_id:
7901 		return &bpf_skb_ancestor_cgroup_id_proto;
7902 #endif
7903 #ifdef CONFIG_INET
7904 	case BPF_FUNC_sk_lookup_tcp:
7905 		return &bpf_sk_lookup_tcp_proto;
7906 	case BPF_FUNC_sk_lookup_udp:
7907 		return &bpf_sk_lookup_udp_proto;
7908 	case BPF_FUNC_sk_release:
7909 		return &bpf_sk_release_proto;
7910 	case BPF_FUNC_tcp_sock:
7911 		return &bpf_tcp_sock_proto;
7912 	case BPF_FUNC_get_listener_sock:
7913 		return &bpf_get_listener_sock_proto;
7914 	case BPF_FUNC_skc_lookup_tcp:
7915 		return &bpf_skc_lookup_tcp_proto;
7916 	case BPF_FUNC_tcp_check_syncookie:
7917 		return &bpf_tcp_check_syncookie_proto;
7918 	case BPF_FUNC_skb_ecn_set_ce:
7919 		return &bpf_skb_ecn_set_ce_proto;
7920 	case BPF_FUNC_tcp_gen_syncookie:
7921 		return &bpf_tcp_gen_syncookie_proto;
7922 	case BPF_FUNC_sk_assign:
7923 		return &bpf_sk_assign_proto;
7924 	case BPF_FUNC_skb_set_tstamp:
7925 		return &bpf_skb_set_tstamp_proto;
7926 #ifdef CONFIG_SYN_COOKIES
7927 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv4:
7928 		return &bpf_tcp_raw_gen_syncookie_ipv4_proto;
7929 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv6:
7930 		return &bpf_tcp_raw_gen_syncookie_ipv6_proto;
7931 	case BPF_FUNC_tcp_raw_check_syncookie_ipv4:
7932 		return &bpf_tcp_raw_check_syncookie_ipv4_proto;
7933 	case BPF_FUNC_tcp_raw_check_syncookie_ipv6:
7934 		return &bpf_tcp_raw_check_syncookie_ipv6_proto;
7935 #endif
7936 #endif
7937 	default:
7938 		return bpf_sk_base_func_proto(func_id);
7939 	}
7940 }
7941 
7942 static const struct bpf_func_proto *
xdp_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7943 xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7944 {
7945 	switch (func_id) {
7946 	case BPF_FUNC_perf_event_output:
7947 		return &bpf_xdp_event_output_proto;
7948 	case BPF_FUNC_get_smp_processor_id:
7949 		return &bpf_get_smp_processor_id_proto;
7950 	case BPF_FUNC_csum_diff:
7951 		return &bpf_csum_diff_proto;
7952 	case BPF_FUNC_xdp_adjust_head:
7953 		return &bpf_xdp_adjust_head_proto;
7954 	case BPF_FUNC_xdp_adjust_meta:
7955 		return &bpf_xdp_adjust_meta_proto;
7956 	case BPF_FUNC_redirect:
7957 		return &bpf_xdp_redirect_proto;
7958 	case BPF_FUNC_redirect_map:
7959 		return &bpf_xdp_redirect_map_proto;
7960 	case BPF_FUNC_xdp_adjust_tail:
7961 		return &bpf_xdp_adjust_tail_proto;
7962 	case BPF_FUNC_xdp_get_buff_len:
7963 		return &bpf_xdp_get_buff_len_proto;
7964 	case BPF_FUNC_xdp_load_bytes:
7965 		return &bpf_xdp_load_bytes_proto;
7966 	case BPF_FUNC_xdp_store_bytes:
7967 		return &bpf_xdp_store_bytes_proto;
7968 	case BPF_FUNC_fib_lookup:
7969 		return &bpf_xdp_fib_lookup_proto;
7970 	case BPF_FUNC_check_mtu:
7971 		return &bpf_xdp_check_mtu_proto;
7972 #ifdef CONFIG_INET
7973 	case BPF_FUNC_sk_lookup_udp:
7974 		return &bpf_xdp_sk_lookup_udp_proto;
7975 	case BPF_FUNC_sk_lookup_tcp:
7976 		return &bpf_xdp_sk_lookup_tcp_proto;
7977 	case BPF_FUNC_sk_release:
7978 		return &bpf_sk_release_proto;
7979 	case BPF_FUNC_skc_lookup_tcp:
7980 		return &bpf_xdp_skc_lookup_tcp_proto;
7981 	case BPF_FUNC_tcp_check_syncookie:
7982 		return &bpf_tcp_check_syncookie_proto;
7983 	case BPF_FUNC_tcp_gen_syncookie:
7984 		return &bpf_tcp_gen_syncookie_proto;
7985 #ifdef CONFIG_SYN_COOKIES
7986 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv4:
7987 		return &bpf_tcp_raw_gen_syncookie_ipv4_proto;
7988 	case BPF_FUNC_tcp_raw_gen_syncookie_ipv6:
7989 		return &bpf_tcp_raw_gen_syncookie_ipv6_proto;
7990 	case BPF_FUNC_tcp_raw_check_syncookie_ipv4:
7991 		return &bpf_tcp_raw_check_syncookie_ipv4_proto;
7992 	case BPF_FUNC_tcp_raw_check_syncookie_ipv6:
7993 		return &bpf_tcp_raw_check_syncookie_ipv6_proto;
7994 #endif
7995 #endif
7996 	default:
7997 		return bpf_sk_base_func_proto(func_id);
7998 	}
7999 
8000 #if IS_MODULE(CONFIG_NF_CONNTRACK) && IS_ENABLED(CONFIG_DEBUG_INFO_BTF_MODULES)
8001 	/* The nf_conn___init type is used in the NF_CONNTRACK kfuncs. The
8002 	 * kfuncs are defined in two different modules, and we want to be able
8003 	 * to use them interchangably with the same BTF type ID. Because modules
8004 	 * can't de-duplicate BTF IDs between each other, we need the type to be
8005 	 * referenced in the vmlinux BTF or the verifier will get confused about
8006 	 * the different types. So we add this dummy type reference which will
8007 	 * be included in vmlinux BTF, allowing both modules to refer to the
8008 	 * same type ID.
8009 	 */
8010 	BTF_TYPE_EMIT(struct nf_conn___init);
8011 #endif
8012 }
8013 
8014 const struct bpf_func_proto bpf_sock_map_update_proto __weak;
8015 const struct bpf_func_proto bpf_sock_hash_update_proto __weak;
8016 
8017 static const struct bpf_func_proto *
sock_ops_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8018 sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8019 {
8020 	const struct bpf_func_proto *func_proto;
8021 
8022 	func_proto = cgroup_common_func_proto(func_id, prog);
8023 	if (func_proto)
8024 		return func_proto;
8025 
8026 	switch (func_id) {
8027 	case BPF_FUNC_setsockopt:
8028 		return &bpf_sock_ops_setsockopt_proto;
8029 	case BPF_FUNC_getsockopt:
8030 		return &bpf_sock_ops_getsockopt_proto;
8031 	case BPF_FUNC_sock_ops_cb_flags_set:
8032 		return &bpf_sock_ops_cb_flags_set_proto;
8033 	case BPF_FUNC_sock_map_update:
8034 		return &bpf_sock_map_update_proto;
8035 	case BPF_FUNC_sock_hash_update:
8036 		return &bpf_sock_hash_update_proto;
8037 	case BPF_FUNC_get_socket_cookie:
8038 		return &bpf_get_socket_cookie_sock_ops_proto;
8039 	case BPF_FUNC_perf_event_output:
8040 		return &bpf_event_output_data_proto;
8041 	case BPF_FUNC_sk_storage_get:
8042 		return &bpf_sk_storage_get_proto;
8043 	case BPF_FUNC_sk_storage_delete:
8044 		return &bpf_sk_storage_delete_proto;
8045 	case BPF_FUNC_get_netns_cookie:
8046 		return &bpf_get_netns_cookie_sock_ops_proto;
8047 #ifdef CONFIG_INET
8048 	case BPF_FUNC_load_hdr_opt:
8049 		return &bpf_sock_ops_load_hdr_opt_proto;
8050 	case BPF_FUNC_store_hdr_opt:
8051 		return &bpf_sock_ops_store_hdr_opt_proto;
8052 	case BPF_FUNC_reserve_hdr_opt:
8053 		return &bpf_sock_ops_reserve_hdr_opt_proto;
8054 	case BPF_FUNC_tcp_sock:
8055 		return &bpf_tcp_sock_proto;
8056 #endif /* CONFIG_INET */
8057 	default:
8058 		return bpf_sk_base_func_proto(func_id);
8059 	}
8060 }
8061 
8062 const struct bpf_func_proto bpf_msg_redirect_map_proto __weak;
8063 const struct bpf_func_proto bpf_msg_redirect_hash_proto __weak;
8064 
8065 static const struct bpf_func_proto *
sk_msg_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8066 sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8067 {
8068 	switch (func_id) {
8069 	case BPF_FUNC_msg_redirect_map:
8070 		return &bpf_msg_redirect_map_proto;
8071 	case BPF_FUNC_msg_redirect_hash:
8072 		return &bpf_msg_redirect_hash_proto;
8073 	case BPF_FUNC_msg_apply_bytes:
8074 		return &bpf_msg_apply_bytes_proto;
8075 	case BPF_FUNC_msg_cork_bytes:
8076 		return &bpf_msg_cork_bytes_proto;
8077 	case BPF_FUNC_msg_pull_data:
8078 		return &bpf_msg_pull_data_proto;
8079 	case BPF_FUNC_msg_push_data:
8080 		return &bpf_msg_push_data_proto;
8081 	case BPF_FUNC_msg_pop_data:
8082 		return &bpf_msg_pop_data_proto;
8083 	case BPF_FUNC_perf_event_output:
8084 		return &bpf_event_output_data_proto;
8085 	case BPF_FUNC_get_current_uid_gid:
8086 		return &bpf_get_current_uid_gid_proto;
8087 	case BPF_FUNC_get_current_pid_tgid:
8088 		return &bpf_get_current_pid_tgid_proto;
8089 	case BPF_FUNC_sk_storage_get:
8090 		return &bpf_sk_storage_get_proto;
8091 	case BPF_FUNC_sk_storage_delete:
8092 		return &bpf_sk_storage_delete_proto;
8093 	case BPF_FUNC_get_netns_cookie:
8094 		return &bpf_get_netns_cookie_sk_msg_proto;
8095 #ifdef CONFIG_CGROUPS
8096 	case BPF_FUNC_get_current_cgroup_id:
8097 		return &bpf_get_current_cgroup_id_proto;
8098 	case BPF_FUNC_get_current_ancestor_cgroup_id:
8099 		return &bpf_get_current_ancestor_cgroup_id_proto;
8100 #endif
8101 #ifdef CONFIG_CGROUP_NET_CLASSID
8102 	case BPF_FUNC_get_cgroup_classid:
8103 		return &bpf_get_cgroup_classid_curr_proto;
8104 #endif
8105 	default:
8106 		return bpf_sk_base_func_proto(func_id);
8107 	}
8108 }
8109 
8110 const struct bpf_func_proto bpf_sk_redirect_map_proto __weak;
8111 const struct bpf_func_proto bpf_sk_redirect_hash_proto __weak;
8112 
8113 static const struct bpf_func_proto *
sk_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8114 sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8115 {
8116 	switch (func_id) {
8117 	case BPF_FUNC_skb_store_bytes:
8118 		return &bpf_skb_store_bytes_proto;
8119 	case BPF_FUNC_skb_load_bytes:
8120 		return &bpf_skb_load_bytes_proto;
8121 	case BPF_FUNC_skb_pull_data:
8122 		return &sk_skb_pull_data_proto;
8123 	case BPF_FUNC_skb_change_tail:
8124 		return &sk_skb_change_tail_proto;
8125 	case BPF_FUNC_skb_change_head:
8126 		return &sk_skb_change_head_proto;
8127 	case BPF_FUNC_skb_adjust_room:
8128 		return &sk_skb_adjust_room_proto;
8129 	case BPF_FUNC_get_socket_cookie:
8130 		return &bpf_get_socket_cookie_proto;
8131 	case BPF_FUNC_get_socket_uid:
8132 		return &bpf_get_socket_uid_proto;
8133 	case BPF_FUNC_sk_redirect_map:
8134 		return &bpf_sk_redirect_map_proto;
8135 	case BPF_FUNC_sk_redirect_hash:
8136 		return &bpf_sk_redirect_hash_proto;
8137 	case BPF_FUNC_perf_event_output:
8138 		return &bpf_skb_event_output_proto;
8139 #ifdef CONFIG_INET
8140 	case BPF_FUNC_sk_lookup_tcp:
8141 		return &bpf_sk_lookup_tcp_proto;
8142 	case BPF_FUNC_sk_lookup_udp:
8143 		return &bpf_sk_lookup_udp_proto;
8144 	case BPF_FUNC_sk_release:
8145 		return &bpf_sk_release_proto;
8146 	case BPF_FUNC_skc_lookup_tcp:
8147 		return &bpf_skc_lookup_tcp_proto;
8148 #endif
8149 	default:
8150 		return bpf_sk_base_func_proto(func_id);
8151 	}
8152 }
8153 
8154 static const struct bpf_func_proto *
flow_dissector_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8155 flow_dissector_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8156 {
8157 	switch (func_id) {
8158 	case BPF_FUNC_skb_load_bytes:
8159 		return &bpf_flow_dissector_load_bytes_proto;
8160 	default:
8161 		return bpf_sk_base_func_proto(func_id);
8162 	}
8163 }
8164 
8165 static const struct bpf_func_proto *
lwt_out_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8166 lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8167 {
8168 	switch (func_id) {
8169 	case BPF_FUNC_skb_load_bytes:
8170 		return &bpf_skb_load_bytes_proto;
8171 	case BPF_FUNC_skb_pull_data:
8172 		return &bpf_skb_pull_data_proto;
8173 	case BPF_FUNC_csum_diff:
8174 		return &bpf_csum_diff_proto;
8175 	case BPF_FUNC_get_cgroup_classid:
8176 		return &bpf_get_cgroup_classid_proto;
8177 	case BPF_FUNC_get_route_realm:
8178 		return &bpf_get_route_realm_proto;
8179 	case BPF_FUNC_get_hash_recalc:
8180 		return &bpf_get_hash_recalc_proto;
8181 	case BPF_FUNC_perf_event_output:
8182 		return &bpf_skb_event_output_proto;
8183 	case BPF_FUNC_get_smp_processor_id:
8184 		return &bpf_get_smp_processor_id_proto;
8185 	case BPF_FUNC_skb_under_cgroup:
8186 		return &bpf_skb_under_cgroup_proto;
8187 	default:
8188 		return bpf_sk_base_func_proto(func_id);
8189 	}
8190 }
8191 
8192 static const struct bpf_func_proto *
lwt_in_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8193 lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8194 {
8195 	switch (func_id) {
8196 	case BPF_FUNC_lwt_push_encap:
8197 		return &bpf_lwt_in_push_encap_proto;
8198 	default:
8199 		return lwt_out_func_proto(func_id, prog);
8200 	}
8201 }
8202 
8203 static const struct bpf_func_proto *
lwt_xmit_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8204 lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8205 {
8206 	switch (func_id) {
8207 	case BPF_FUNC_skb_get_tunnel_key:
8208 		return &bpf_skb_get_tunnel_key_proto;
8209 	case BPF_FUNC_skb_set_tunnel_key:
8210 		return bpf_get_skb_set_tunnel_proto(func_id);
8211 	case BPF_FUNC_skb_get_tunnel_opt:
8212 		return &bpf_skb_get_tunnel_opt_proto;
8213 	case BPF_FUNC_skb_set_tunnel_opt:
8214 		return bpf_get_skb_set_tunnel_proto(func_id);
8215 	case BPF_FUNC_redirect:
8216 		return &bpf_redirect_proto;
8217 	case BPF_FUNC_clone_redirect:
8218 		return &bpf_clone_redirect_proto;
8219 	case BPF_FUNC_skb_change_tail:
8220 		return &bpf_skb_change_tail_proto;
8221 	case BPF_FUNC_skb_change_head:
8222 		return &bpf_skb_change_head_proto;
8223 	case BPF_FUNC_skb_store_bytes:
8224 		return &bpf_skb_store_bytes_proto;
8225 	case BPF_FUNC_csum_update:
8226 		return &bpf_csum_update_proto;
8227 	case BPF_FUNC_csum_level:
8228 		return &bpf_csum_level_proto;
8229 	case BPF_FUNC_l3_csum_replace:
8230 		return &bpf_l3_csum_replace_proto;
8231 	case BPF_FUNC_l4_csum_replace:
8232 		return &bpf_l4_csum_replace_proto;
8233 	case BPF_FUNC_set_hash_invalid:
8234 		return &bpf_set_hash_invalid_proto;
8235 	case BPF_FUNC_lwt_push_encap:
8236 		return &bpf_lwt_xmit_push_encap_proto;
8237 	default:
8238 		return lwt_out_func_proto(func_id, prog);
8239 	}
8240 }
8241 
8242 static const struct bpf_func_proto *
lwt_seg6local_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8243 lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8244 {
8245 	switch (func_id) {
8246 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
8247 	case BPF_FUNC_lwt_seg6_store_bytes:
8248 		return &bpf_lwt_seg6_store_bytes_proto;
8249 	case BPF_FUNC_lwt_seg6_action:
8250 		return &bpf_lwt_seg6_action_proto;
8251 	case BPF_FUNC_lwt_seg6_adjust_srh:
8252 		return &bpf_lwt_seg6_adjust_srh_proto;
8253 #endif
8254 	default:
8255 		return lwt_out_func_proto(func_id, prog);
8256 	}
8257 }
8258 
bpf_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8259 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
8260 				    const struct bpf_prog *prog,
8261 				    struct bpf_insn_access_aux *info)
8262 {
8263 	const int size_default = sizeof(__u32);
8264 
8265 	if (off < 0 || off >= sizeof(struct __sk_buff))
8266 		return false;
8267 
8268 	/* The verifier guarantees that size > 0. */
8269 	if (off % size != 0)
8270 		return false;
8271 
8272 	switch (off) {
8273 	case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8274 		if (off + size > offsetofend(struct __sk_buff, cb[4]))
8275 			return false;
8276 		break;
8277 	case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
8278 	case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
8279 	case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
8280 	case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
8281 	case bpf_ctx_range(struct __sk_buff, data):
8282 	case bpf_ctx_range(struct __sk_buff, data_meta):
8283 	case bpf_ctx_range(struct __sk_buff, data_end):
8284 		if (size != size_default)
8285 			return false;
8286 		break;
8287 	case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
8288 		return false;
8289 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
8290 		if (type == BPF_WRITE || size != sizeof(__u64))
8291 			return false;
8292 		break;
8293 	case bpf_ctx_range(struct __sk_buff, tstamp):
8294 		if (size != sizeof(__u64))
8295 			return false;
8296 		break;
8297 	case offsetof(struct __sk_buff, sk):
8298 		if (type == BPF_WRITE || size != sizeof(__u64))
8299 			return false;
8300 		info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
8301 		break;
8302 	case offsetof(struct __sk_buff, tstamp_type):
8303 		return false;
8304 	case offsetofend(struct __sk_buff, tstamp_type) ... offsetof(struct __sk_buff, hwtstamp) - 1:
8305 		/* Explicitly prohibit access to padding in __sk_buff. */
8306 		return false;
8307 	default:
8308 		/* Only narrow read access allowed for now. */
8309 		if (type == BPF_WRITE) {
8310 			if (size != size_default)
8311 				return false;
8312 		} else {
8313 			bpf_ctx_record_field_size(info, size_default);
8314 			if (!bpf_ctx_narrow_access_ok(off, size, size_default))
8315 				return false;
8316 		}
8317 	}
8318 
8319 	return true;
8320 }
8321 
sk_filter_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8322 static bool sk_filter_is_valid_access(int off, int size,
8323 				      enum bpf_access_type type,
8324 				      const struct bpf_prog *prog,
8325 				      struct bpf_insn_access_aux *info)
8326 {
8327 	switch (off) {
8328 	case bpf_ctx_range(struct __sk_buff, tc_classid):
8329 	case bpf_ctx_range(struct __sk_buff, data):
8330 	case bpf_ctx_range(struct __sk_buff, data_meta):
8331 	case bpf_ctx_range(struct __sk_buff, data_end):
8332 	case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8333 	case bpf_ctx_range(struct __sk_buff, tstamp):
8334 	case bpf_ctx_range(struct __sk_buff, wire_len):
8335 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
8336 		return false;
8337 	}
8338 
8339 	if (type == BPF_WRITE) {
8340 		switch (off) {
8341 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8342 			break;
8343 		default:
8344 			return false;
8345 		}
8346 	}
8347 
8348 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8349 }
8350 
cg_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8351 static bool cg_skb_is_valid_access(int off, int size,
8352 				   enum bpf_access_type type,
8353 				   const struct bpf_prog *prog,
8354 				   struct bpf_insn_access_aux *info)
8355 {
8356 	switch (off) {
8357 	case bpf_ctx_range(struct __sk_buff, tc_classid):
8358 	case bpf_ctx_range(struct __sk_buff, data_meta):
8359 	case bpf_ctx_range(struct __sk_buff, wire_len):
8360 		return false;
8361 	case bpf_ctx_range(struct __sk_buff, data):
8362 	case bpf_ctx_range(struct __sk_buff, data_end):
8363 		if (!bpf_capable())
8364 			return false;
8365 		break;
8366 	}
8367 
8368 	if (type == BPF_WRITE) {
8369 		switch (off) {
8370 		case bpf_ctx_range(struct __sk_buff, mark):
8371 		case bpf_ctx_range(struct __sk_buff, priority):
8372 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8373 			break;
8374 		case bpf_ctx_range(struct __sk_buff, tstamp):
8375 			if (!bpf_capable())
8376 				return false;
8377 			break;
8378 		default:
8379 			return false;
8380 		}
8381 	}
8382 
8383 	switch (off) {
8384 	case bpf_ctx_range(struct __sk_buff, data):
8385 		info->reg_type = PTR_TO_PACKET;
8386 		break;
8387 	case bpf_ctx_range(struct __sk_buff, data_end):
8388 		info->reg_type = PTR_TO_PACKET_END;
8389 		break;
8390 	}
8391 
8392 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8393 }
8394 
lwt_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8395 static bool lwt_is_valid_access(int off, int size,
8396 				enum bpf_access_type type,
8397 				const struct bpf_prog *prog,
8398 				struct bpf_insn_access_aux *info)
8399 {
8400 	switch (off) {
8401 	case bpf_ctx_range(struct __sk_buff, tc_classid):
8402 	case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8403 	case bpf_ctx_range(struct __sk_buff, data_meta):
8404 	case bpf_ctx_range(struct __sk_buff, tstamp):
8405 	case bpf_ctx_range(struct __sk_buff, wire_len):
8406 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
8407 		return false;
8408 	}
8409 
8410 	if (type == BPF_WRITE) {
8411 		switch (off) {
8412 		case bpf_ctx_range(struct __sk_buff, mark):
8413 		case bpf_ctx_range(struct __sk_buff, priority):
8414 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8415 			break;
8416 		default:
8417 			return false;
8418 		}
8419 	}
8420 
8421 	switch (off) {
8422 	case bpf_ctx_range(struct __sk_buff, data):
8423 		info->reg_type = PTR_TO_PACKET;
8424 		break;
8425 	case bpf_ctx_range(struct __sk_buff, data_end):
8426 		info->reg_type = PTR_TO_PACKET_END;
8427 		break;
8428 	}
8429 
8430 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8431 }
8432 
8433 /* Attach type specific accesses */
__sock_filter_check_attach_type(int off,enum bpf_access_type access_type,enum bpf_attach_type attach_type)8434 static bool __sock_filter_check_attach_type(int off,
8435 					    enum bpf_access_type access_type,
8436 					    enum bpf_attach_type attach_type)
8437 {
8438 	switch (off) {
8439 	case offsetof(struct bpf_sock, bound_dev_if):
8440 	case offsetof(struct bpf_sock, mark):
8441 	case offsetof(struct bpf_sock, priority):
8442 		switch (attach_type) {
8443 		case BPF_CGROUP_INET_SOCK_CREATE:
8444 		case BPF_CGROUP_INET_SOCK_RELEASE:
8445 			goto full_access;
8446 		default:
8447 			return false;
8448 		}
8449 	case bpf_ctx_range(struct bpf_sock, src_ip4):
8450 		switch (attach_type) {
8451 		case BPF_CGROUP_INET4_POST_BIND:
8452 			goto read_only;
8453 		default:
8454 			return false;
8455 		}
8456 	case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
8457 		switch (attach_type) {
8458 		case BPF_CGROUP_INET6_POST_BIND:
8459 			goto read_only;
8460 		default:
8461 			return false;
8462 		}
8463 	case bpf_ctx_range(struct bpf_sock, src_port):
8464 		switch (attach_type) {
8465 		case BPF_CGROUP_INET4_POST_BIND:
8466 		case BPF_CGROUP_INET6_POST_BIND:
8467 			goto read_only;
8468 		default:
8469 			return false;
8470 		}
8471 	}
8472 read_only:
8473 	return access_type == BPF_READ;
8474 full_access:
8475 	return true;
8476 }
8477 
bpf_sock_common_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)8478 bool bpf_sock_common_is_valid_access(int off, int size,
8479 				     enum bpf_access_type type,
8480 				     struct bpf_insn_access_aux *info)
8481 {
8482 	switch (off) {
8483 	case bpf_ctx_range_till(struct bpf_sock, type, priority):
8484 		return false;
8485 	default:
8486 		return bpf_sock_is_valid_access(off, size, type, info);
8487 	}
8488 }
8489 
bpf_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)8490 bool bpf_sock_is_valid_access(int off, int size, enum bpf_access_type type,
8491 			      struct bpf_insn_access_aux *info)
8492 {
8493 	const int size_default = sizeof(__u32);
8494 	int field_size;
8495 
8496 	if (off < 0 || off >= sizeof(struct bpf_sock))
8497 		return false;
8498 	if (off % size != 0)
8499 		return false;
8500 
8501 	switch (off) {
8502 	case offsetof(struct bpf_sock, state):
8503 	case offsetof(struct bpf_sock, family):
8504 	case offsetof(struct bpf_sock, type):
8505 	case offsetof(struct bpf_sock, protocol):
8506 	case offsetof(struct bpf_sock, src_port):
8507 	case offsetof(struct bpf_sock, rx_queue_mapping):
8508 	case bpf_ctx_range(struct bpf_sock, src_ip4):
8509 	case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
8510 	case bpf_ctx_range(struct bpf_sock, dst_ip4):
8511 	case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
8512 		bpf_ctx_record_field_size(info, size_default);
8513 		return bpf_ctx_narrow_access_ok(off, size, size_default);
8514 	case bpf_ctx_range(struct bpf_sock, dst_port):
8515 		field_size = size == size_default ?
8516 			size_default : sizeof_field(struct bpf_sock, dst_port);
8517 		bpf_ctx_record_field_size(info, field_size);
8518 		return bpf_ctx_narrow_access_ok(off, size, field_size);
8519 	case offsetofend(struct bpf_sock, dst_port) ...
8520 	     offsetof(struct bpf_sock, dst_ip4) - 1:
8521 		return false;
8522 	}
8523 
8524 	return size == size_default;
8525 }
8526 
sock_filter_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8527 static bool sock_filter_is_valid_access(int off, int size,
8528 					enum bpf_access_type type,
8529 					const struct bpf_prog *prog,
8530 					struct bpf_insn_access_aux *info)
8531 {
8532 	if (!bpf_sock_is_valid_access(off, size, type, info))
8533 		return false;
8534 	return __sock_filter_check_attach_type(off, type,
8535 					       prog->expected_attach_type);
8536 }
8537 
bpf_noop_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8538 static int bpf_noop_prologue(struct bpf_insn *insn_buf, bool direct_write,
8539 			     const struct bpf_prog *prog)
8540 {
8541 	/* Neither direct read nor direct write requires any preliminary
8542 	 * action.
8543 	 */
8544 	return 0;
8545 }
8546 
bpf_unclone_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog,int drop_verdict)8547 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
8548 				const struct bpf_prog *prog, int drop_verdict)
8549 {
8550 	struct bpf_insn *insn = insn_buf;
8551 
8552 	if (!direct_write)
8553 		return 0;
8554 
8555 	/* if (!skb->cloned)
8556 	 *       goto start;
8557 	 *
8558 	 * (Fast-path, otherwise approximation that we might be
8559 	 *  a clone, do the rest in helper.)
8560 	 */
8561 	*insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET);
8562 	*insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
8563 	*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
8564 
8565 	/* ret = bpf_skb_pull_data(skb, 0); */
8566 	*insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
8567 	*insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
8568 	*insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
8569 			       BPF_FUNC_skb_pull_data);
8570 	/* if (!ret)
8571 	 *      goto restore;
8572 	 * return TC_ACT_SHOT;
8573 	 */
8574 	*insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
8575 	*insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
8576 	*insn++ = BPF_EXIT_INSN();
8577 
8578 	/* restore: */
8579 	*insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
8580 	/* start: */
8581 	*insn++ = prog->insnsi[0];
8582 
8583 	return insn - insn_buf;
8584 }
8585 
bpf_gen_ld_abs(const struct bpf_insn * orig,struct bpf_insn * insn_buf)8586 static int bpf_gen_ld_abs(const struct bpf_insn *orig,
8587 			  struct bpf_insn *insn_buf)
8588 {
8589 	bool indirect = BPF_MODE(orig->code) == BPF_IND;
8590 	struct bpf_insn *insn = insn_buf;
8591 
8592 	if (!indirect) {
8593 		*insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm);
8594 	} else {
8595 		*insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg);
8596 		if (orig->imm)
8597 			*insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm);
8598 	}
8599 	/* We're guaranteed here that CTX is in R6. */
8600 	*insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX);
8601 
8602 	switch (BPF_SIZE(orig->code)) {
8603 	case BPF_B:
8604 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache);
8605 		break;
8606 	case BPF_H:
8607 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache);
8608 		break;
8609 	case BPF_W:
8610 		*insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache);
8611 		break;
8612 	}
8613 
8614 	*insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2);
8615 	*insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0);
8616 	*insn++ = BPF_EXIT_INSN();
8617 
8618 	return insn - insn_buf;
8619 }
8620 
tc_cls_act_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8621 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
8622 			       const struct bpf_prog *prog)
8623 {
8624 	return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
8625 }
8626 
tc_cls_act_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8627 static bool tc_cls_act_is_valid_access(int off, int size,
8628 				       enum bpf_access_type type,
8629 				       const struct bpf_prog *prog,
8630 				       struct bpf_insn_access_aux *info)
8631 {
8632 	if (type == BPF_WRITE) {
8633 		switch (off) {
8634 		case bpf_ctx_range(struct __sk_buff, mark):
8635 		case bpf_ctx_range(struct __sk_buff, tc_index):
8636 		case bpf_ctx_range(struct __sk_buff, priority):
8637 		case bpf_ctx_range(struct __sk_buff, tc_classid):
8638 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8639 		case bpf_ctx_range(struct __sk_buff, tstamp):
8640 		case bpf_ctx_range(struct __sk_buff, queue_mapping):
8641 			break;
8642 		default:
8643 			return false;
8644 		}
8645 	}
8646 
8647 	switch (off) {
8648 	case bpf_ctx_range(struct __sk_buff, data):
8649 		info->reg_type = PTR_TO_PACKET;
8650 		break;
8651 	case bpf_ctx_range(struct __sk_buff, data_meta):
8652 		info->reg_type = PTR_TO_PACKET_META;
8653 		break;
8654 	case bpf_ctx_range(struct __sk_buff, data_end):
8655 		info->reg_type = PTR_TO_PACKET_END;
8656 		break;
8657 	case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8658 		return false;
8659 	case offsetof(struct __sk_buff, tstamp_type):
8660 		/* The convert_ctx_access() on reading and writing
8661 		 * __sk_buff->tstamp depends on whether the bpf prog
8662 		 * has used __sk_buff->tstamp_type or not.
8663 		 * Thus, we need to set prog->tstamp_type_access
8664 		 * earlier during is_valid_access() here.
8665 		 */
8666 		((struct bpf_prog *)prog)->tstamp_type_access = 1;
8667 		return size == sizeof(__u8);
8668 	}
8669 
8670 	return bpf_skb_is_valid_access(off, size, type, prog, info);
8671 }
8672 
8673 DEFINE_MUTEX(nf_conn_btf_access_lock);
8674 EXPORT_SYMBOL_GPL(nf_conn_btf_access_lock);
8675 
8676 int (*nfct_btf_struct_access)(struct bpf_verifier_log *log, const struct btf *btf,
8677 			      const struct btf_type *t, int off, int size,
8678 			      enum bpf_access_type atype, u32 *next_btf_id,
8679 			      enum bpf_type_flag *flag);
8680 EXPORT_SYMBOL_GPL(nfct_btf_struct_access);
8681 
tc_cls_act_btf_struct_access(struct bpf_verifier_log * log,const struct btf * btf,const struct btf_type * t,int off,int size,enum bpf_access_type atype,u32 * next_btf_id,enum bpf_type_flag * flag)8682 static int tc_cls_act_btf_struct_access(struct bpf_verifier_log *log,
8683 					const struct btf *btf,
8684 					const struct btf_type *t, int off,
8685 					int size, enum bpf_access_type atype,
8686 					u32 *next_btf_id,
8687 					enum bpf_type_flag *flag)
8688 {
8689 	int ret = -EACCES;
8690 
8691 	if (atype == BPF_READ)
8692 		return btf_struct_access(log, btf, t, off, size, atype, next_btf_id,
8693 					 flag);
8694 
8695 	mutex_lock(&nf_conn_btf_access_lock);
8696 	if (nfct_btf_struct_access)
8697 		ret = nfct_btf_struct_access(log, btf, t, off, size, atype, next_btf_id, flag);
8698 	mutex_unlock(&nf_conn_btf_access_lock);
8699 
8700 	return ret;
8701 }
8702 
__is_valid_xdp_access(int off,int size)8703 static bool __is_valid_xdp_access(int off, int size)
8704 {
8705 	if (off < 0 || off >= sizeof(struct xdp_md))
8706 		return false;
8707 	if (off % size != 0)
8708 		return false;
8709 	if (size != sizeof(__u32))
8710 		return false;
8711 
8712 	return true;
8713 }
8714 
xdp_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8715 static bool xdp_is_valid_access(int off, int size,
8716 				enum bpf_access_type type,
8717 				const struct bpf_prog *prog,
8718 				struct bpf_insn_access_aux *info)
8719 {
8720 	if (prog->expected_attach_type != BPF_XDP_DEVMAP) {
8721 		switch (off) {
8722 		case offsetof(struct xdp_md, egress_ifindex):
8723 			return false;
8724 		}
8725 	}
8726 
8727 	if (type == BPF_WRITE) {
8728 		if (bpf_prog_is_dev_bound(prog->aux)) {
8729 			switch (off) {
8730 			case offsetof(struct xdp_md, rx_queue_index):
8731 				return __is_valid_xdp_access(off, size);
8732 			}
8733 		}
8734 		return false;
8735 	}
8736 
8737 	switch (off) {
8738 	case offsetof(struct xdp_md, data):
8739 		info->reg_type = PTR_TO_PACKET;
8740 		break;
8741 	case offsetof(struct xdp_md, data_meta):
8742 		info->reg_type = PTR_TO_PACKET_META;
8743 		break;
8744 	case offsetof(struct xdp_md, data_end):
8745 		info->reg_type = PTR_TO_PACKET_END;
8746 		break;
8747 	}
8748 
8749 	return __is_valid_xdp_access(off, size);
8750 }
8751 
bpf_warn_invalid_xdp_action(struct net_device * dev,struct bpf_prog * prog,u32 act)8752 void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act)
8753 {
8754 	const u32 act_max = XDP_REDIRECT;
8755 
8756 	pr_warn_once("%s XDP return value %u on prog %s (id %d) dev %s, expect packet loss!\n",
8757 		     act > act_max ? "Illegal" : "Driver unsupported",
8758 		     act, prog->aux->name, prog->aux->id, dev ? dev->name : "N/A");
8759 }
8760 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
8761 
xdp_btf_struct_access(struct bpf_verifier_log * log,const struct btf * btf,const struct btf_type * t,int off,int size,enum bpf_access_type atype,u32 * next_btf_id,enum bpf_type_flag * flag)8762 static int xdp_btf_struct_access(struct bpf_verifier_log *log,
8763 				 const struct btf *btf,
8764 				 const struct btf_type *t, int off,
8765 				 int size, enum bpf_access_type atype,
8766 				 u32 *next_btf_id,
8767 				 enum bpf_type_flag *flag)
8768 {
8769 	int ret = -EACCES;
8770 
8771 	if (atype == BPF_READ)
8772 		return btf_struct_access(log, btf, t, off, size, atype, next_btf_id,
8773 					 flag);
8774 
8775 	mutex_lock(&nf_conn_btf_access_lock);
8776 	if (nfct_btf_struct_access)
8777 		ret = nfct_btf_struct_access(log, btf, t, off, size, atype, next_btf_id, flag);
8778 	mutex_unlock(&nf_conn_btf_access_lock);
8779 
8780 	return ret;
8781 }
8782 
sock_addr_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8783 static bool sock_addr_is_valid_access(int off, int size,
8784 				      enum bpf_access_type type,
8785 				      const struct bpf_prog *prog,
8786 				      struct bpf_insn_access_aux *info)
8787 {
8788 	const int size_default = sizeof(__u32);
8789 
8790 	if (off < 0 || off >= sizeof(struct bpf_sock_addr))
8791 		return false;
8792 	if (off % size != 0)
8793 		return false;
8794 
8795 	/* Disallow access to IPv6 fields from IPv4 contex and vise
8796 	 * versa.
8797 	 */
8798 	switch (off) {
8799 	case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
8800 		switch (prog->expected_attach_type) {
8801 		case BPF_CGROUP_INET4_BIND:
8802 		case BPF_CGROUP_INET4_CONNECT:
8803 		case BPF_CGROUP_INET4_GETPEERNAME:
8804 		case BPF_CGROUP_INET4_GETSOCKNAME:
8805 		case BPF_CGROUP_UDP4_SENDMSG:
8806 		case BPF_CGROUP_UDP4_RECVMSG:
8807 			break;
8808 		default:
8809 			return false;
8810 		}
8811 		break;
8812 	case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
8813 		switch (prog->expected_attach_type) {
8814 		case BPF_CGROUP_INET6_BIND:
8815 		case BPF_CGROUP_INET6_CONNECT:
8816 		case BPF_CGROUP_INET6_GETPEERNAME:
8817 		case BPF_CGROUP_INET6_GETSOCKNAME:
8818 		case BPF_CGROUP_UDP6_SENDMSG:
8819 		case BPF_CGROUP_UDP6_RECVMSG:
8820 			break;
8821 		default:
8822 			return false;
8823 		}
8824 		break;
8825 	case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
8826 		switch (prog->expected_attach_type) {
8827 		case BPF_CGROUP_UDP4_SENDMSG:
8828 			break;
8829 		default:
8830 			return false;
8831 		}
8832 		break;
8833 	case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
8834 				msg_src_ip6[3]):
8835 		switch (prog->expected_attach_type) {
8836 		case BPF_CGROUP_UDP6_SENDMSG:
8837 			break;
8838 		default:
8839 			return false;
8840 		}
8841 		break;
8842 	}
8843 
8844 	switch (off) {
8845 	case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
8846 	case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
8847 	case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
8848 	case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
8849 				msg_src_ip6[3]):
8850 	case bpf_ctx_range(struct bpf_sock_addr, user_port):
8851 		if (type == BPF_READ) {
8852 			bpf_ctx_record_field_size(info, size_default);
8853 
8854 			if (bpf_ctx_wide_access_ok(off, size,
8855 						   struct bpf_sock_addr,
8856 						   user_ip6))
8857 				return true;
8858 
8859 			if (bpf_ctx_wide_access_ok(off, size,
8860 						   struct bpf_sock_addr,
8861 						   msg_src_ip6))
8862 				return true;
8863 
8864 			if (!bpf_ctx_narrow_access_ok(off, size, size_default))
8865 				return false;
8866 		} else {
8867 			if (bpf_ctx_wide_access_ok(off, size,
8868 						   struct bpf_sock_addr,
8869 						   user_ip6))
8870 				return true;
8871 
8872 			if (bpf_ctx_wide_access_ok(off, size,
8873 						   struct bpf_sock_addr,
8874 						   msg_src_ip6))
8875 				return true;
8876 
8877 			if (size != size_default)
8878 				return false;
8879 		}
8880 		break;
8881 	case offsetof(struct bpf_sock_addr, sk):
8882 		if (type != BPF_READ)
8883 			return false;
8884 		if (size != sizeof(__u64))
8885 			return false;
8886 		info->reg_type = PTR_TO_SOCKET;
8887 		break;
8888 	default:
8889 		if (type == BPF_READ) {
8890 			if (size != size_default)
8891 				return false;
8892 		} else {
8893 			return false;
8894 		}
8895 	}
8896 
8897 	return true;
8898 }
8899 
sock_ops_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8900 static bool sock_ops_is_valid_access(int off, int size,
8901 				     enum bpf_access_type type,
8902 				     const struct bpf_prog *prog,
8903 				     struct bpf_insn_access_aux *info)
8904 {
8905 	const int size_default = sizeof(__u32);
8906 
8907 	if (off < 0 || off >= sizeof(struct bpf_sock_ops))
8908 		return false;
8909 
8910 	/* The verifier guarantees that size > 0. */
8911 	if (off % size != 0)
8912 		return false;
8913 
8914 	if (type == BPF_WRITE) {
8915 		switch (off) {
8916 		case offsetof(struct bpf_sock_ops, reply):
8917 		case offsetof(struct bpf_sock_ops, sk_txhash):
8918 			if (size != size_default)
8919 				return false;
8920 			break;
8921 		default:
8922 			return false;
8923 		}
8924 	} else {
8925 		switch (off) {
8926 		case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received,
8927 					bytes_acked):
8928 			if (size != sizeof(__u64))
8929 				return false;
8930 			break;
8931 		case offsetof(struct bpf_sock_ops, sk):
8932 			if (size != sizeof(__u64))
8933 				return false;
8934 			info->reg_type = PTR_TO_SOCKET_OR_NULL;
8935 			break;
8936 		case offsetof(struct bpf_sock_ops, skb_data):
8937 			if (size != sizeof(__u64))
8938 				return false;
8939 			info->reg_type = PTR_TO_PACKET;
8940 			break;
8941 		case offsetof(struct bpf_sock_ops, skb_data_end):
8942 			if (size != sizeof(__u64))
8943 				return false;
8944 			info->reg_type = PTR_TO_PACKET_END;
8945 			break;
8946 		case offsetof(struct bpf_sock_ops, skb_tcp_flags):
8947 			bpf_ctx_record_field_size(info, size_default);
8948 			return bpf_ctx_narrow_access_ok(off, size,
8949 							size_default);
8950 		default:
8951 			if (size != size_default)
8952 				return false;
8953 			break;
8954 		}
8955 	}
8956 
8957 	return true;
8958 }
8959 
sk_skb_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8960 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
8961 			   const struct bpf_prog *prog)
8962 {
8963 	return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
8964 }
8965 
sk_skb_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8966 static bool sk_skb_is_valid_access(int off, int size,
8967 				   enum bpf_access_type type,
8968 				   const struct bpf_prog *prog,
8969 				   struct bpf_insn_access_aux *info)
8970 {
8971 	switch (off) {
8972 	case bpf_ctx_range(struct __sk_buff, tc_classid):
8973 	case bpf_ctx_range(struct __sk_buff, data_meta):
8974 	case bpf_ctx_range(struct __sk_buff, tstamp):
8975 	case bpf_ctx_range(struct __sk_buff, wire_len):
8976 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
8977 		return false;
8978 	}
8979 
8980 	if (type == BPF_WRITE) {
8981 		switch (off) {
8982 		case bpf_ctx_range(struct __sk_buff, tc_index):
8983 		case bpf_ctx_range(struct __sk_buff, priority):
8984 			break;
8985 		default:
8986 			return false;
8987 		}
8988 	}
8989 
8990 	switch (off) {
8991 	case bpf_ctx_range(struct __sk_buff, mark):
8992 		return false;
8993 	case bpf_ctx_range(struct __sk_buff, data):
8994 		info->reg_type = PTR_TO_PACKET;
8995 		break;
8996 	case bpf_ctx_range(struct __sk_buff, data_end):
8997 		info->reg_type = PTR_TO_PACKET_END;
8998 		break;
8999 	}
9000 
9001 	return bpf_skb_is_valid_access(off, size, type, prog, info);
9002 }
9003 
sk_msg_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)9004 static bool sk_msg_is_valid_access(int off, int size,
9005 				   enum bpf_access_type type,
9006 				   const struct bpf_prog *prog,
9007 				   struct bpf_insn_access_aux *info)
9008 {
9009 	if (type == BPF_WRITE)
9010 		return false;
9011 
9012 	if (off % size != 0)
9013 		return false;
9014 
9015 	switch (off) {
9016 	case offsetof(struct sk_msg_md, data):
9017 		info->reg_type = PTR_TO_PACKET;
9018 		if (size != sizeof(__u64))
9019 			return false;
9020 		break;
9021 	case offsetof(struct sk_msg_md, data_end):
9022 		info->reg_type = PTR_TO_PACKET_END;
9023 		if (size != sizeof(__u64))
9024 			return false;
9025 		break;
9026 	case offsetof(struct sk_msg_md, sk):
9027 		if (size != sizeof(__u64))
9028 			return false;
9029 		info->reg_type = PTR_TO_SOCKET;
9030 		break;
9031 	case bpf_ctx_range(struct sk_msg_md, family):
9032 	case bpf_ctx_range(struct sk_msg_md, remote_ip4):
9033 	case bpf_ctx_range(struct sk_msg_md, local_ip4):
9034 	case bpf_ctx_range_till(struct sk_msg_md, remote_ip6[0], remote_ip6[3]):
9035 	case bpf_ctx_range_till(struct sk_msg_md, local_ip6[0], local_ip6[3]):
9036 	case bpf_ctx_range(struct sk_msg_md, remote_port):
9037 	case bpf_ctx_range(struct sk_msg_md, local_port):
9038 	case bpf_ctx_range(struct sk_msg_md, size):
9039 		if (size != sizeof(__u32))
9040 			return false;
9041 		break;
9042 	default:
9043 		return false;
9044 	}
9045 	return true;
9046 }
9047 
flow_dissector_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)9048 static bool flow_dissector_is_valid_access(int off, int size,
9049 					   enum bpf_access_type type,
9050 					   const struct bpf_prog *prog,
9051 					   struct bpf_insn_access_aux *info)
9052 {
9053 	const int size_default = sizeof(__u32);
9054 
9055 	if (off < 0 || off >= sizeof(struct __sk_buff))
9056 		return false;
9057 
9058 	if (type == BPF_WRITE)
9059 		return false;
9060 
9061 	switch (off) {
9062 	case bpf_ctx_range(struct __sk_buff, data):
9063 		if (size != size_default)
9064 			return false;
9065 		info->reg_type = PTR_TO_PACKET;
9066 		return true;
9067 	case bpf_ctx_range(struct __sk_buff, data_end):
9068 		if (size != size_default)
9069 			return false;
9070 		info->reg_type = PTR_TO_PACKET_END;
9071 		return true;
9072 	case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
9073 		if (size != sizeof(__u64))
9074 			return false;
9075 		info->reg_type = PTR_TO_FLOW_KEYS;
9076 		return true;
9077 	default:
9078 		return false;
9079 	}
9080 }
9081 
flow_dissector_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9082 static u32 flow_dissector_convert_ctx_access(enum bpf_access_type type,
9083 					     const struct bpf_insn *si,
9084 					     struct bpf_insn *insn_buf,
9085 					     struct bpf_prog *prog,
9086 					     u32 *target_size)
9087 
9088 {
9089 	struct bpf_insn *insn = insn_buf;
9090 
9091 	switch (si->off) {
9092 	case offsetof(struct __sk_buff, data):
9093 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data),
9094 				      si->dst_reg, si->src_reg,
9095 				      offsetof(struct bpf_flow_dissector, data));
9096 		break;
9097 
9098 	case offsetof(struct __sk_buff, data_end):
9099 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data_end),
9100 				      si->dst_reg, si->src_reg,
9101 				      offsetof(struct bpf_flow_dissector, data_end));
9102 		break;
9103 
9104 	case offsetof(struct __sk_buff, flow_keys):
9105 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, flow_keys),
9106 				      si->dst_reg, si->src_reg,
9107 				      offsetof(struct bpf_flow_dissector, flow_keys));
9108 		break;
9109 	}
9110 
9111 	return insn - insn_buf;
9112 }
9113 
bpf_convert_tstamp_type_read(const struct bpf_insn * si,struct bpf_insn * insn)9114 static struct bpf_insn *bpf_convert_tstamp_type_read(const struct bpf_insn *si,
9115 						     struct bpf_insn *insn)
9116 {
9117 	__u8 value_reg = si->dst_reg;
9118 	__u8 skb_reg = si->src_reg;
9119 	/* AX is needed because src_reg and dst_reg could be the same */
9120 	__u8 tmp_reg = BPF_REG_AX;
9121 
9122 	*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg,
9123 			      PKT_VLAN_PRESENT_OFFSET);
9124 	*insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg,
9125 				SKB_MONO_DELIVERY_TIME_MASK, 2);
9126 	*insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_UNSPEC);
9127 	*insn++ = BPF_JMP_A(1);
9128 	*insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_DELIVERY_MONO);
9129 
9130 	return insn;
9131 }
9132 
bpf_convert_shinfo_access(const struct bpf_insn * si,struct bpf_insn * insn)9133 static struct bpf_insn *bpf_convert_shinfo_access(const struct bpf_insn *si,
9134 						  struct bpf_insn *insn)
9135 {
9136 	/* si->dst_reg = skb_shinfo(SKB); */
9137 #ifdef NET_SKBUFF_DATA_USES_OFFSET
9138 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
9139 			      BPF_REG_AX, si->src_reg,
9140 			      offsetof(struct sk_buff, end));
9141 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, head),
9142 			      si->dst_reg, si->src_reg,
9143 			      offsetof(struct sk_buff, head));
9144 	*insn++ = BPF_ALU64_REG(BPF_ADD, si->dst_reg, BPF_REG_AX);
9145 #else
9146 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
9147 			      si->dst_reg, si->src_reg,
9148 			      offsetof(struct sk_buff, end));
9149 #endif
9150 
9151 	return insn;
9152 }
9153 
bpf_convert_tstamp_read(const struct bpf_prog * prog,const struct bpf_insn * si,struct bpf_insn * insn)9154 static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_prog *prog,
9155 						const struct bpf_insn *si,
9156 						struct bpf_insn *insn)
9157 {
9158 	__u8 value_reg = si->dst_reg;
9159 	__u8 skb_reg = si->src_reg;
9160 
9161 #ifdef CONFIG_NET_CLS_ACT
9162 	/* If the tstamp_type is read,
9163 	 * the bpf prog is aware the tstamp could have delivery time.
9164 	 * Thus, read skb->tstamp as is if tstamp_type_access is true.
9165 	 */
9166 	if (!prog->tstamp_type_access) {
9167 		/* AX is needed because src_reg and dst_reg could be the same */
9168 		__u8 tmp_reg = BPF_REG_AX;
9169 
9170 		*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, PKT_VLAN_PRESENT_OFFSET);
9171 		*insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg,
9172 					TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK);
9173 		*insn++ = BPF_JMP32_IMM(BPF_JNE, tmp_reg,
9174 					TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK, 2);
9175 		/* skb->tc_at_ingress && skb->mono_delivery_time,
9176 		 * read 0 as the (rcv) timestamp.
9177 		 */
9178 		*insn++ = BPF_MOV64_IMM(value_reg, 0);
9179 		*insn++ = BPF_JMP_A(1);
9180 	}
9181 #endif
9182 
9183 	*insn++ = BPF_LDX_MEM(BPF_DW, value_reg, skb_reg,
9184 			      offsetof(struct sk_buff, tstamp));
9185 	return insn;
9186 }
9187 
bpf_convert_tstamp_write(const struct bpf_prog * prog,const struct bpf_insn * si,struct bpf_insn * insn)9188 static struct bpf_insn *bpf_convert_tstamp_write(const struct bpf_prog *prog,
9189 						 const struct bpf_insn *si,
9190 						 struct bpf_insn *insn)
9191 {
9192 	__u8 value_reg = si->src_reg;
9193 	__u8 skb_reg = si->dst_reg;
9194 
9195 #ifdef CONFIG_NET_CLS_ACT
9196 	/* If the tstamp_type is read,
9197 	 * the bpf prog is aware the tstamp could have delivery time.
9198 	 * Thus, write skb->tstamp as is if tstamp_type_access is true.
9199 	 * Otherwise, writing at ingress will have to clear the
9200 	 * mono_delivery_time bit also.
9201 	 */
9202 	if (!prog->tstamp_type_access) {
9203 		__u8 tmp_reg = BPF_REG_AX;
9204 
9205 		*insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, PKT_VLAN_PRESENT_OFFSET);
9206 		/* Writing __sk_buff->tstamp as ingress, goto <clear> */
9207 		*insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, TC_AT_INGRESS_MASK, 1);
9208 		/* goto <store> */
9209 		*insn++ = BPF_JMP_A(2);
9210 		/* <clear>: mono_delivery_time */
9211 		*insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, ~SKB_MONO_DELIVERY_TIME_MASK);
9212 		*insn++ = BPF_STX_MEM(BPF_B, skb_reg, tmp_reg, PKT_VLAN_PRESENT_OFFSET);
9213 	}
9214 #endif
9215 
9216 	/* <store>: skb->tstamp = tstamp */
9217 	*insn++ = BPF_STX_MEM(BPF_DW, skb_reg, value_reg,
9218 			      offsetof(struct sk_buff, tstamp));
9219 	return insn;
9220 }
9221 
bpf_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9222 static u32 bpf_convert_ctx_access(enum bpf_access_type type,
9223 				  const struct bpf_insn *si,
9224 				  struct bpf_insn *insn_buf,
9225 				  struct bpf_prog *prog, u32 *target_size)
9226 {
9227 	struct bpf_insn *insn = insn_buf;
9228 	int off;
9229 
9230 	switch (si->off) {
9231 	case offsetof(struct __sk_buff, len):
9232 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9233 				      bpf_target_off(struct sk_buff, len, 4,
9234 						     target_size));
9235 		break;
9236 
9237 	case offsetof(struct __sk_buff, protocol):
9238 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9239 				      bpf_target_off(struct sk_buff, protocol, 2,
9240 						     target_size));
9241 		break;
9242 
9243 	case offsetof(struct __sk_buff, vlan_proto):
9244 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9245 				      bpf_target_off(struct sk_buff, vlan_proto, 2,
9246 						     target_size));
9247 		break;
9248 
9249 	case offsetof(struct __sk_buff, priority):
9250 		if (type == BPF_WRITE)
9251 			*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9252 					      bpf_target_off(struct sk_buff, priority, 4,
9253 							     target_size));
9254 		else
9255 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9256 					      bpf_target_off(struct sk_buff, priority, 4,
9257 							     target_size));
9258 		break;
9259 
9260 	case offsetof(struct __sk_buff, ingress_ifindex):
9261 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9262 				      bpf_target_off(struct sk_buff, skb_iif, 4,
9263 						     target_size));
9264 		break;
9265 
9266 	case offsetof(struct __sk_buff, ifindex):
9267 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
9268 				      si->dst_reg, si->src_reg,
9269 				      offsetof(struct sk_buff, dev));
9270 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
9271 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9272 				      bpf_target_off(struct net_device, ifindex, 4,
9273 						     target_size));
9274 		break;
9275 
9276 	case offsetof(struct __sk_buff, hash):
9277 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9278 				      bpf_target_off(struct sk_buff, hash, 4,
9279 						     target_size));
9280 		break;
9281 
9282 	case offsetof(struct __sk_buff, mark):
9283 		if (type == BPF_WRITE)
9284 			*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9285 					      bpf_target_off(struct sk_buff, mark, 4,
9286 							     target_size));
9287 		else
9288 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9289 					      bpf_target_off(struct sk_buff, mark, 4,
9290 							     target_size));
9291 		break;
9292 
9293 	case offsetof(struct __sk_buff, pkt_type):
9294 		*target_size = 1;
9295 		*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
9296 				      PKT_TYPE_OFFSET);
9297 		*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
9298 #ifdef __BIG_ENDIAN_BITFIELD
9299 		*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
9300 #endif
9301 		break;
9302 
9303 	case offsetof(struct __sk_buff, queue_mapping):
9304 		if (type == BPF_WRITE) {
9305 			*insn++ = BPF_JMP_IMM(BPF_JGE, si->src_reg, NO_QUEUE_MAPPING, 1);
9306 			*insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
9307 					      bpf_target_off(struct sk_buff,
9308 							     queue_mapping,
9309 							     2, target_size));
9310 		} else {
9311 			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9312 					      bpf_target_off(struct sk_buff,
9313 							     queue_mapping,
9314 							     2, target_size));
9315 		}
9316 		break;
9317 
9318 	case offsetof(struct __sk_buff, vlan_present):
9319 		*target_size = 1;
9320 		*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
9321 				      PKT_VLAN_PRESENT_OFFSET);
9322 		if (PKT_VLAN_PRESENT_BIT)
9323 			*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, PKT_VLAN_PRESENT_BIT);
9324 		if (PKT_VLAN_PRESENT_BIT < 7)
9325 			*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
9326 		break;
9327 
9328 	case offsetof(struct __sk_buff, vlan_tci):
9329 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9330 				      bpf_target_off(struct sk_buff, vlan_tci, 2,
9331 						     target_size));
9332 		break;
9333 
9334 	case offsetof(struct __sk_buff, cb[0]) ...
9335 	     offsetofend(struct __sk_buff, cb[4]) - 1:
9336 		BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, data) < 20);
9337 		BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
9338 			      offsetof(struct qdisc_skb_cb, data)) %
9339 			     sizeof(__u64));
9340 
9341 		prog->cb_access = 1;
9342 		off  = si->off;
9343 		off -= offsetof(struct __sk_buff, cb[0]);
9344 		off += offsetof(struct sk_buff, cb);
9345 		off += offsetof(struct qdisc_skb_cb, data);
9346 		if (type == BPF_WRITE)
9347 			*insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
9348 					      si->src_reg, off);
9349 		else
9350 			*insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
9351 					      si->src_reg, off);
9352 		break;
9353 
9354 	case offsetof(struct __sk_buff, tc_classid):
9355 		BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, tc_classid) != 2);
9356 
9357 		off  = si->off;
9358 		off -= offsetof(struct __sk_buff, tc_classid);
9359 		off += offsetof(struct sk_buff, cb);
9360 		off += offsetof(struct qdisc_skb_cb, tc_classid);
9361 		*target_size = 2;
9362 		if (type == BPF_WRITE)
9363 			*insn++ = BPF_STX_MEM(BPF_H, si->dst_reg,
9364 					      si->src_reg, off);
9365 		else
9366 			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
9367 					      si->src_reg, off);
9368 		break;
9369 
9370 	case offsetof(struct __sk_buff, data):
9371 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
9372 				      si->dst_reg, si->src_reg,
9373 				      offsetof(struct sk_buff, data));
9374 		break;
9375 
9376 	case offsetof(struct __sk_buff, data_meta):
9377 		off  = si->off;
9378 		off -= offsetof(struct __sk_buff, data_meta);
9379 		off += offsetof(struct sk_buff, cb);
9380 		off += offsetof(struct bpf_skb_data_end, data_meta);
9381 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
9382 				      si->src_reg, off);
9383 		break;
9384 
9385 	case offsetof(struct __sk_buff, data_end):
9386 		off  = si->off;
9387 		off -= offsetof(struct __sk_buff, data_end);
9388 		off += offsetof(struct sk_buff, cb);
9389 		off += offsetof(struct bpf_skb_data_end, data_end);
9390 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
9391 				      si->src_reg, off);
9392 		break;
9393 
9394 	case offsetof(struct __sk_buff, tc_index):
9395 #ifdef CONFIG_NET_SCHED
9396 		if (type == BPF_WRITE)
9397 			*insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
9398 					      bpf_target_off(struct sk_buff, tc_index, 2,
9399 							     target_size));
9400 		else
9401 			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9402 					      bpf_target_off(struct sk_buff, tc_index, 2,
9403 							     target_size));
9404 #else
9405 		*target_size = 2;
9406 		if (type == BPF_WRITE)
9407 			*insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
9408 		else
9409 			*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9410 #endif
9411 		break;
9412 
9413 	case offsetof(struct __sk_buff, napi_id):
9414 #if defined(CONFIG_NET_RX_BUSY_POLL)
9415 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9416 				      bpf_target_off(struct sk_buff, napi_id, 4,
9417 						     target_size));
9418 		*insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
9419 		*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9420 #else
9421 		*target_size = 4;
9422 		*insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9423 #endif
9424 		break;
9425 	case offsetof(struct __sk_buff, family):
9426 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
9427 
9428 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9429 				      si->dst_reg, si->src_reg,
9430 				      offsetof(struct sk_buff, sk));
9431 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9432 				      bpf_target_off(struct sock_common,
9433 						     skc_family,
9434 						     2, target_size));
9435 		break;
9436 	case offsetof(struct __sk_buff, remote_ip4):
9437 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
9438 
9439 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9440 				      si->dst_reg, si->src_reg,
9441 				      offsetof(struct sk_buff, sk));
9442 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9443 				      bpf_target_off(struct sock_common,
9444 						     skc_daddr,
9445 						     4, target_size));
9446 		break;
9447 	case offsetof(struct __sk_buff, local_ip4):
9448 		BUILD_BUG_ON(sizeof_field(struct sock_common,
9449 					  skc_rcv_saddr) != 4);
9450 
9451 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9452 				      si->dst_reg, si->src_reg,
9453 				      offsetof(struct sk_buff, sk));
9454 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9455 				      bpf_target_off(struct sock_common,
9456 						     skc_rcv_saddr,
9457 						     4, target_size));
9458 		break;
9459 	case offsetof(struct __sk_buff, remote_ip6[0]) ...
9460 	     offsetof(struct __sk_buff, remote_ip6[3]):
9461 #if IS_ENABLED(CONFIG_IPV6)
9462 		BUILD_BUG_ON(sizeof_field(struct sock_common,
9463 					  skc_v6_daddr.s6_addr32[0]) != 4);
9464 
9465 		off = si->off;
9466 		off -= offsetof(struct __sk_buff, remote_ip6[0]);
9467 
9468 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9469 				      si->dst_reg, si->src_reg,
9470 				      offsetof(struct sk_buff, sk));
9471 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9472 				      offsetof(struct sock_common,
9473 					       skc_v6_daddr.s6_addr32[0]) +
9474 				      off);
9475 #else
9476 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9477 #endif
9478 		break;
9479 	case offsetof(struct __sk_buff, local_ip6[0]) ...
9480 	     offsetof(struct __sk_buff, local_ip6[3]):
9481 #if IS_ENABLED(CONFIG_IPV6)
9482 		BUILD_BUG_ON(sizeof_field(struct sock_common,
9483 					  skc_v6_rcv_saddr.s6_addr32[0]) != 4);
9484 
9485 		off = si->off;
9486 		off -= offsetof(struct __sk_buff, local_ip6[0]);
9487 
9488 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9489 				      si->dst_reg, si->src_reg,
9490 				      offsetof(struct sk_buff, sk));
9491 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9492 				      offsetof(struct sock_common,
9493 					       skc_v6_rcv_saddr.s6_addr32[0]) +
9494 				      off);
9495 #else
9496 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9497 #endif
9498 		break;
9499 
9500 	case offsetof(struct __sk_buff, remote_port):
9501 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
9502 
9503 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9504 				      si->dst_reg, si->src_reg,
9505 				      offsetof(struct sk_buff, sk));
9506 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9507 				      bpf_target_off(struct sock_common,
9508 						     skc_dport,
9509 						     2, target_size));
9510 #ifndef __BIG_ENDIAN_BITFIELD
9511 		*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
9512 #endif
9513 		break;
9514 
9515 	case offsetof(struct __sk_buff, local_port):
9516 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
9517 
9518 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9519 				      si->dst_reg, si->src_reg,
9520 				      offsetof(struct sk_buff, sk));
9521 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9522 				      bpf_target_off(struct sock_common,
9523 						     skc_num, 2, target_size));
9524 		break;
9525 
9526 	case offsetof(struct __sk_buff, tstamp):
9527 		BUILD_BUG_ON(sizeof_field(struct sk_buff, tstamp) != 8);
9528 
9529 		if (type == BPF_WRITE)
9530 			insn = bpf_convert_tstamp_write(prog, si, insn);
9531 		else
9532 			insn = bpf_convert_tstamp_read(prog, si, insn);
9533 		break;
9534 
9535 	case offsetof(struct __sk_buff, tstamp_type):
9536 		insn = bpf_convert_tstamp_type_read(si, insn);
9537 		break;
9538 
9539 	case offsetof(struct __sk_buff, gso_segs):
9540 		insn = bpf_convert_shinfo_access(si, insn);
9541 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_segs),
9542 				      si->dst_reg, si->dst_reg,
9543 				      bpf_target_off(struct skb_shared_info,
9544 						     gso_segs, 2,
9545 						     target_size));
9546 		break;
9547 	case offsetof(struct __sk_buff, gso_size):
9548 		insn = bpf_convert_shinfo_access(si, insn);
9549 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_size),
9550 				      si->dst_reg, si->dst_reg,
9551 				      bpf_target_off(struct skb_shared_info,
9552 						     gso_size, 2,
9553 						     target_size));
9554 		break;
9555 	case offsetof(struct __sk_buff, wire_len):
9556 		BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, pkt_len) != 4);
9557 
9558 		off = si->off;
9559 		off -= offsetof(struct __sk_buff, wire_len);
9560 		off += offsetof(struct sk_buff, cb);
9561 		off += offsetof(struct qdisc_skb_cb, pkt_len);
9562 		*target_size = 4;
9563 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, off);
9564 		break;
9565 
9566 	case offsetof(struct __sk_buff, sk):
9567 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9568 				      si->dst_reg, si->src_reg,
9569 				      offsetof(struct sk_buff, sk));
9570 		break;
9571 	case offsetof(struct __sk_buff, hwtstamp):
9572 		BUILD_BUG_ON(sizeof_field(struct skb_shared_hwtstamps, hwtstamp) != 8);
9573 		BUILD_BUG_ON(offsetof(struct skb_shared_hwtstamps, hwtstamp) != 0);
9574 
9575 		insn = bpf_convert_shinfo_access(si, insn);
9576 		*insn++ = BPF_LDX_MEM(BPF_DW,
9577 				      si->dst_reg, si->dst_reg,
9578 				      bpf_target_off(struct skb_shared_info,
9579 						     hwtstamps, 8,
9580 						     target_size));
9581 		break;
9582 	}
9583 
9584 	return insn - insn_buf;
9585 }
9586 
bpf_sock_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9587 u32 bpf_sock_convert_ctx_access(enum bpf_access_type type,
9588 				const struct bpf_insn *si,
9589 				struct bpf_insn *insn_buf,
9590 				struct bpf_prog *prog, u32 *target_size)
9591 {
9592 	struct bpf_insn *insn = insn_buf;
9593 	int off;
9594 
9595 	switch (si->off) {
9596 	case offsetof(struct bpf_sock, bound_dev_if):
9597 		BUILD_BUG_ON(sizeof_field(struct sock, sk_bound_dev_if) != 4);
9598 
9599 		if (type == BPF_WRITE)
9600 			*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9601 					offsetof(struct sock, sk_bound_dev_if));
9602 		else
9603 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9604 				      offsetof(struct sock, sk_bound_dev_if));
9605 		break;
9606 
9607 	case offsetof(struct bpf_sock, mark):
9608 		BUILD_BUG_ON(sizeof_field(struct sock, sk_mark) != 4);
9609 
9610 		if (type == BPF_WRITE)
9611 			*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9612 					offsetof(struct sock, sk_mark));
9613 		else
9614 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9615 				      offsetof(struct sock, sk_mark));
9616 		break;
9617 
9618 	case offsetof(struct bpf_sock, priority):
9619 		BUILD_BUG_ON(sizeof_field(struct sock, sk_priority) != 4);
9620 
9621 		if (type == BPF_WRITE)
9622 			*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9623 					offsetof(struct sock, sk_priority));
9624 		else
9625 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9626 				      offsetof(struct sock, sk_priority));
9627 		break;
9628 
9629 	case offsetof(struct bpf_sock, family):
9630 		*insn++ = BPF_LDX_MEM(
9631 			BPF_FIELD_SIZEOF(struct sock_common, skc_family),
9632 			si->dst_reg, si->src_reg,
9633 			bpf_target_off(struct sock_common,
9634 				       skc_family,
9635 				       sizeof_field(struct sock_common,
9636 						    skc_family),
9637 				       target_size));
9638 		break;
9639 
9640 	case offsetof(struct bpf_sock, type):
9641 		*insn++ = BPF_LDX_MEM(
9642 			BPF_FIELD_SIZEOF(struct sock, sk_type),
9643 			si->dst_reg, si->src_reg,
9644 			bpf_target_off(struct sock, sk_type,
9645 				       sizeof_field(struct sock, sk_type),
9646 				       target_size));
9647 		break;
9648 
9649 	case offsetof(struct bpf_sock, protocol):
9650 		*insn++ = BPF_LDX_MEM(
9651 			BPF_FIELD_SIZEOF(struct sock, sk_protocol),
9652 			si->dst_reg, si->src_reg,
9653 			bpf_target_off(struct sock, sk_protocol,
9654 				       sizeof_field(struct sock, sk_protocol),
9655 				       target_size));
9656 		break;
9657 
9658 	case offsetof(struct bpf_sock, src_ip4):
9659 		*insn++ = BPF_LDX_MEM(
9660 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9661 			bpf_target_off(struct sock_common, skc_rcv_saddr,
9662 				       sizeof_field(struct sock_common,
9663 						    skc_rcv_saddr),
9664 				       target_size));
9665 		break;
9666 
9667 	case offsetof(struct bpf_sock, dst_ip4):
9668 		*insn++ = BPF_LDX_MEM(
9669 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9670 			bpf_target_off(struct sock_common, skc_daddr,
9671 				       sizeof_field(struct sock_common,
9672 						    skc_daddr),
9673 				       target_size));
9674 		break;
9675 
9676 	case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
9677 #if IS_ENABLED(CONFIG_IPV6)
9678 		off = si->off;
9679 		off -= offsetof(struct bpf_sock, src_ip6[0]);
9680 		*insn++ = BPF_LDX_MEM(
9681 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9682 			bpf_target_off(
9683 				struct sock_common,
9684 				skc_v6_rcv_saddr.s6_addr32[0],
9685 				sizeof_field(struct sock_common,
9686 					     skc_v6_rcv_saddr.s6_addr32[0]),
9687 				target_size) + off);
9688 #else
9689 		(void)off;
9690 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9691 #endif
9692 		break;
9693 
9694 	case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
9695 #if IS_ENABLED(CONFIG_IPV6)
9696 		off = si->off;
9697 		off -= offsetof(struct bpf_sock, dst_ip6[0]);
9698 		*insn++ = BPF_LDX_MEM(
9699 			BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9700 			bpf_target_off(struct sock_common,
9701 				       skc_v6_daddr.s6_addr32[0],
9702 				       sizeof_field(struct sock_common,
9703 						    skc_v6_daddr.s6_addr32[0]),
9704 				       target_size) + off);
9705 #else
9706 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9707 		*target_size = 4;
9708 #endif
9709 		break;
9710 
9711 	case offsetof(struct bpf_sock, src_port):
9712 		*insn++ = BPF_LDX_MEM(
9713 			BPF_FIELD_SIZEOF(struct sock_common, skc_num),
9714 			si->dst_reg, si->src_reg,
9715 			bpf_target_off(struct sock_common, skc_num,
9716 				       sizeof_field(struct sock_common,
9717 						    skc_num),
9718 				       target_size));
9719 		break;
9720 
9721 	case offsetof(struct bpf_sock, dst_port):
9722 		*insn++ = BPF_LDX_MEM(
9723 			BPF_FIELD_SIZEOF(struct sock_common, skc_dport),
9724 			si->dst_reg, si->src_reg,
9725 			bpf_target_off(struct sock_common, skc_dport,
9726 				       sizeof_field(struct sock_common,
9727 						    skc_dport),
9728 				       target_size));
9729 		break;
9730 
9731 	case offsetof(struct bpf_sock, state):
9732 		*insn++ = BPF_LDX_MEM(
9733 			BPF_FIELD_SIZEOF(struct sock_common, skc_state),
9734 			si->dst_reg, si->src_reg,
9735 			bpf_target_off(struct sock_common, skc_state,
9736 				       sizeof_field(struct sock_common,
9737 						    skc_state),
9738 				       target_size));
9739 		break;
9740 	case offsetof(struct bpf_sock, rx_queue_mapping):
9741 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
9742 		*insn++ = BPF_LDX_MEM(
9743 			BPF_FIELD_SIZEOF(struct sock, sk_rx_queue_mapping),
9744 			si->dst_reg, si->src_reg,
9745 			bpf_target_off(struct sock, sk_rx_queue_mapping,
9746 				       sizeof_field(struct sock,
9747 						    sk_rx_queue_mapping),
9748 				       target_size));
9749 		*insn++ = BPF_JMP_IMM(BPF_JNE, si->dst_reg, NO_QUEUE_MAPPING,
9750 				      1);
9751 		*insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
9752 #else
9753 		*insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
9754 		*target_size = 2;
9755 #endif
9756 		break;
9757 	}
9758 
9759 	return insn - insn_buf;
9760 }
9761 
tc_cls_act_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9762 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
9763 					 const struct bpf_insn *si,
9764 					 struct bpf_insn *insn_buf,
9765 					 struct bpf_prog *prog, u32 *target_size)
9766 {
9767 	struct bpf_insn *insn = insn_buf;
9768 
9769 	switch (si->off) {
9770 	case offsetof(struct __sk_buff, ifindex):
9771 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
9772 				      si->dst_reg, si->src_reg,
9773 				      offsetof(struct sk_buff, dev));
9774 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9775 				      bpf_target_off(struct net_device, ifindex, 4,
9776 						     target_size));
9777 		break;
9778 	default:
9779 		return bpf_convert_ctx_access(type, si, insn_buf, prog,
9780 					      target_size);
9781 	}
9782 
9783 	return insn - insn_buf;
9784 }
9785 
xdp_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9786 static u32 xdp_convert_ctx_access(enum bpf_access_type type,
9787 				  const struct bpf_insn *si,
9788 				  struct bpf_insn *insn_buf,
9789 				  struct bpf_prog *prog, u32 *target_size)
9790 {
9791 	struct bpf_insn *insn = insn_buf;
9792 
9793 	switch (si->off) {
9794 	case offsetof(struct xdp_md, data):
9795 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
9796 				      si->dst_reg, si->src_reg,
9797 				      offsetof(struct xdp_buff, data));
9798 		break;
9799 	case offsetof(struct xdp_md, data_meta):
9800 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
9801 				      si->dst_reg, si->src_reg,
9802 				      offsetof(struct xdp_buff, data_meta));
9803 		break;
9804 	case offsetof(struct xdp_md, data_end):
9805 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
9806 				      si->dst_reg, si->src_reg,
9807 				      offsetof(struct xdp_buff, data_end));
9808 		break;
9809 	case offsetof(struct xdp_md, ingress_ifindex):
9810 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
9811 				      si->dst_reg, si->src_reg,
9812 				      offsetof(struct xdp_buff, rxq));
9813 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
9814 				      si->dst_reg, si->dst_reg,
9815 				      offsetof(struct xdp_rxq_info, dev));
9816 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9817 				      offsetof(struct net_device, ifindex));
9818 		break;
9819 	case offsetof(struct xdp_md, rx_queue_index):
9820 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
9821 				      si->dst_reg, si->src_reg,
9822 				      offsetof(struct xdp_buff, rxq));
9823 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9824 				      offsetof(struct xdp_rxq_info,
9825 					       queue_index));
9826 		break;
9827 	case offsetof(struct xdp_md, egress_ifindex):
9828 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, txq),
9829 				      si->dst_reg, si->src_reg,
9830 				      offsetof(struct xdp_buff, txq));
9831 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_txq_info, dev),
9832 				      si->dst_reg, si->dst_reg,
9833 				      offsetof(struct xdp_txq_info, dev));
9834 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9835 				      offsetof(struct net_device, ifindex));
9836 		break;
9837 	}
9838 
9839 	return insn - insn_buf;
9840 }
9841 
9842 /* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of
9843  * context Structure, F is Field in context structure that contains a pointer
9844  * to Nested Structure of type NS that has the field NF.
9845  *
9846  * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make
9847  * sure that SIZE is not greater than actual size of S.F.NF.
9848  *
9849  * If offset OFF is provided, the load happens from that offset relative to
9850  * offset of NF.
9851  */
9852 #define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF)	       \
9853 	do {								       \
9854 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg,     \
9855 				      si->src_reg, offsetof(S, F));	       \
9856 		*insn++ = BPF_LDX_MEM(					       \
9857 			SIZE, si->dst_reg, si->dst_reg,			       \
9858 			bpf_target_off(NS, NF, sizeof_field(NS, NF),	       \
9859 				       target_size)			       \
9860 				+ OFF);					       \
9861 	} while (0)
9862 
9863 #define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF)			       \
9864 	SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF,		       \
9865 					     BPF_FIELD_SIZEOF(NS, NF), 0)
9866 
9867 /* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to
9868  * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation.
9869  *
9870  * In addition it uses Temporary Field TF (member of struct S) as the 3rd
9871  * "register" since two registers available in convert_ctx_access are not
9872  * enough: we can't override neither SRC, since it contains value to store, nor
9873  * DST since it contains pointer to context that may be used by later
9874  * instructions. But we need a temporary place to save pointer to nested
9875  * structure whose field we want to store to.
9876  */
9877 #define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE, OFF, TF)	       \
9878 	do {								       \
9879 		int tmp_reg = BPF_REG_9;				       \
9880 		if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg)	       \
9881 			--tmp_reg;					       \
9882 		if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg)	       \
9883 			--tmp_reg;					       \
9884 		*insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg,	       \
9885 				      offsetof(S, TF));			       \
9886 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg,	       \
9887 				      si->dst_reg, offsetof(S, F));	       \
9888 		*insn++ = BPF_STX_MEM(SIZE, tmp_reg, si->src_reg,	       \
9889 			bpf_target_off(NS, NF, sizeof_field(NS, NF),	       \
9890 				       target_size)			       \
9891 				+ OFF);					       \
9892 		*insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg,	       \
9893 				      offsetof(S, TF));			       \
9894 	} while (0)
9895 
9896 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \
9897 						      TF)		       \
9898 	do {								       \
9899 		if (type == BPF_WRITE) {				       \
9900 			SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE,   \
9901 							 OFF, TF);	       \
9902 		} else {						       \
9903 			SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(		       \
9904 				S, NS, F, NF, SIZE, OFF);  \
9905 		}							       \
9906 	} while (0)
9907 
9908 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF)		       \
9909 	SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(			       \
9910 		S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF)
9911 
sock_addr_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)9912 static u32 sock_addr_convert_ctx_access(enum bpf_access_type type,
9913 					const struct bpf_insn *si,
9914 					struct bpf_insn *insn_buf,
9915 					struct bpf_prog *prog, u32 *target_size)
9916 {
9917 	int off, port_size = sizeof_field(struct sockaddr_in6, sin6_port);
9918 	struct bpf_insn *insn = insn_buf;
9919 
9920 	switch (si->off) {
9921 	case offsetof(struct bpf_sock_addr, user_family):
9922 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9923 					    struct sockaddr, uaddr, sa_family);
9924 		break;
9925 
9926 	case offsetof(struct bpf_sock_addr, user_ip4):
9927 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9928 			struct bpf_sock_addr_kern, struct sockaddr_in, uaddr,
9929 			sin_addr, BPF_SIZE(si->code), 0, tmp_reg);
9930 		break;
9931 
9932 	case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
9933 		off = si->off;
9934 		off -= offsetof(struct bpf_sock_addr, user_ip6[0]);
9935 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9936 			struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
9937 			sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off,
9938 			tmp_reg);
9939 		break;
9940 
9941 	case offsetof(struct bpf_sock_addr, user_port):
9942 		/* To get port we need to know sa_family first and then treat
9943 		 * sockaddr as either sockaddr_in or sockaddr_in6.
9944 		 * Though we can simplify since port field has same offset and
9945 		 * size in both structures.
9946 		 * Here we check this invariant and use just one of the
9947 		 * structures if it's true.
9948 		 */
9949 		BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) !=
9950 			     offsetof(struct sockaddr_in6, sin6_port));
9951 		BUILD_BUG_ON(sizeof_field(struct sockaddr_in, sin_port) !=
9952 			     sizeof_field(struct sockaddr_in6, sin6_port));
9953 		/* Account for sin6_port being smaller than user_port. */
9954 		port_size = min(port_size, BPF_LDST_BYTES(si));
9955 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9956 			struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
9957 			sin6_port, bytes_to_bpf_size(port_size), 0, tmp_reg);
9958 		break;
9959 
9960 	case offsetof(struct bpf_sock_addr, family):
9961 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9962 					    struct sock, sk, sk_family);
9963 		break;
9964 
9965 	case offsetof(struct bpf_sock_addr, type):
9966 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9967 					    struct sock, sk, sk_type);
9968 		break;
9969 
9970 	case offsetof(struct bpf_sock_addr, protocol):
9971 		SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9972 					    struct sock, sk, sk_protocol);
9973 		break;
9974 
9975 	case offsetof(struct bpf_sock_addr, msg_src_ip4):
9976 		/* Treat t_ctx as struct in_addr for msg_src_ip4. */
9977 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9978 			struct bpf_sock_addr_kern, struct in_addr, t_ctx,
9979 			s_addr, BPF_SIZE(si->code), 0, tmp_reg);
9980 		break;
9981 
9982 	case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
9983 				msg_src_ip6[3]):
9984 		off = si->off;
9985 		off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]);
9986 		/* Treat t_ctx as struct in6_addr for msg_src_ip6. */
9987 		SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9988 			struct bpf_sock_addr_kern, struct in6_addr, t_ctx,
9989 			s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg);
9990 		break;
9991 	case offsetof(struct bpf_sock_addr, sk):
9992 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_addr_kern, sk),
9993 				      si->dst_reg, si->src_reg,
9994 				      offsetof(struct bpf_sock_addr_kern, sk));
9995 		break;
9996 	}
9997 
9998 	return insn - insn_buf;
9999 }
10000 
sock_ops_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10001 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
10002 				       const struct bpf_insn *si,
10003 				       struct bpf_insn *insn_buf,
10004 				       struct bpf_prog *prog,
10005 				       u32 *target_size)
10006 {
10007 	struct bpf_insn *insn = insn_buf;
10008 	int off;
10009 
10010 /* Helper macro for adding read access to tcp_sock or sock fields. */
10011 #define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)			      \
10012 	do {								      \
10013 		int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 2;     \
10014 		BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) >		      \
10015 			     sizeof_field(struct bpf_sock_ops, BPF_FIELD));   \
10016 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10017 			reg--;						      \
10018 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10019 			reg--;						      \
10020 		if (si->dst_reg == si->src_reg) {			      \
10021 			*insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg,	      \
10022 					  offsetof(struct bpf_sock_ops_kern,  \
10023 					  temp));			      \
10024 			fullsock_reg = reg;				      \
10025 			jmp += 2;					      \
10026 		}							      \
10027 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10028 						struct bpf_sock_ops_kern,     \
10029 						is_fullsock),		      \
10030 				      fullsock_reg, si->src_reg,	      \
10031 				      offsetof(struct bpf_sock_ops_kern,      \
10032 					       is_fullsock));		      \
10033 		*insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp);	      \
10034 		if (si->dst_reg == si->src_reg)				      \
10035 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10036 				      offsetof(struct bpf_sock_ops_kern,      \
10037 				      temp));				      \
10038 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10039 						struct bpf_sock_ops_kern, sk),\
10040 				      si->dst_reg, si->src_reg,		      \
10041 				      offsetof(struct bpf_sock_ops_kern, sk));\
10042 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ,		      \
10043 						       OBJ_FIELD),	      \
10044 				      si->dst_reg, si->dst_reg,		      \
10045 				      offsetof(OBJ, OBJ_FIELD));	      \
10046 		if (si->dst_reg == si->src_reg)	{			      \
10047 			*insn++ = BPF_JMP_A(1);				      \
10048 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10049 				      offsetof(struct bpf_sock_ops_kern,      \
10050 				      temp));				      \
10051 		}							      \
10052 	} while (0)
10053 
10054 #define SOCK_OPS_GET_SK()							      \
10055 	do {								      \
10056 		int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 1;     \
10057 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10058 			reg--;						      \
10059 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10060 			reg--;						      \
10061 		if (si->dst_reg == si->src_reg) {			      \
10062 			*insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg,	      \
10063 					  offsetof(struct bpf_sock_ops_kern,  \
10064 					  temp));			      \
10065 			fullsock_reg = reg;				      \
10066 			jmp += 2;					      \
10067 		}							      \
10068 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10069 						struct bpf_sock_ops_kern,     \
10070 						is_fullsock),		      \
10071 				      fullsock_reg, si->src_reg,	      \
10072 				      offsetof(struct bpf_sock_ops_kern,      \
10073 					       is_fullsock));		      \
10074 		*insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp);	      \
10075 		if (si->dst_reg == si->src_reg)				      \
10076 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10077 				      offsetof(struct bpf_sock_ops_kern,      \
10078 				      temp));				      \
10079 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10080 						struct bpf_sock_ops_kern, sk),\
10081 				      si->dst_reg, si->src_reg,		      \
10082 				      offsetof(struct bpf_sock_ops_kern, sk));\
10083 		if (si->dst_reg == si->src_reg)	{			      \
10084 			*insn++ = BPF_JMP_A(1);				      \
10085 			*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg,	      \
10086 				      offsetof(struct bpf_sock_ops_kern,      \
10087 				      temp));				      \
10088 		}							      \
10089 	} while (0)
10090 
10091 #define SOCK_OPS_GET_TCP_SOCK_FIELD(FIELD) \
10092 		SOCK_OPS_GET_FIELD(FIELD, FIELD, struct tcp_sock)
10093 
10094 /* Helper macro for adding write access to tcp_sock or sock fields.
10095  * The macro is called with two registers, dst_reg which contains a pointer
10096  * to ctx (context) and src_reg which contains the value that should be
10097  * stored. However, we need an additional register since we cannot overwrite
10098  * dst_reg because it may be used later in the program.
10099  * Instead we "borrow" one of the other register. We first save its value
10100  * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore
10101  * it at the end of the macro.
10102  */
10103 #define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)			      \
10104 	do {								      \
10105 		int reg = BPF_REG_9;					      \
10106 		BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) >		      \
10107 			     sizeof_field(struct bpf_sock_ops, BPF_FIELD));   \
10108 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10109 			reg--;						      \
10110 		if (si->dst_reg == reg || si->src_reg == reg)		      \
10111 			reg--;						      \
10112 		*insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg,		      \
10113 				      offsetof(struct bpf_sock_ops_kern,      \
10114 					       temp));			      \
10115 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10116 						struct bpf_sock_ops_kern,     \
10117 						is_fullsock),		      \
10118 				      reg, si->dst_reg,			      \
10119 				      offsetof(struct bpf_sock_ops_kern,      \
10120 					       is_fullsock));		      \
10121 		*insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2);		      \
10122 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(			      \
10123 						struct bpf_sock_ops_kern, sk),\
10124 				      reg, si->dst_reg,			      \
10125 				      offsetof(struct bpf_sock_ops_kern, sk));\
10126 		*insn++ = BPF_STX_MEM(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD),	      \
10127 				      reg, si->src_reg,			      \
10128 				      offsetof(OBJ, OBJ_FIELD));	      \
10129 		*insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg,		      \
10130 				      offsetof(struct bpf_sock_ops_kern,      \
10131 					       temp));			      \
10132 	} while (0)
10133 
10134 #define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE)	      \
10135 	do {								      \
10136 		if (TYPE == BPF_WRITE)					      \
10137 			SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);	      \
10138 		else							      \
10139 			SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ);	      \
10140 	} while (0)
10141 
10142 	if (insn > insn_buf)
10143 		return insn - insn_buf;
10144 
10145 	switch (si->off) {
10146 	case offsetof(struct bpf_sock_ops, op):
10147 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10148 						       op),
10149 				      si->dst_reg, si->src_reg,
10150 				      offsetof(struct bpf_sock_ops_kern, op));
10151 		break;
10152 
10153 	case offsetof(struct bpf_sock_ops, replylong[0]) ...
10154 	     offsetof(struct bpf_sock_ops, replylong[3]):
10155 		BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, reply) !=
10156 			     sizeof_field(struct bpf_sock_ops_kern, reply));
10157 		BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, replylong) !=
10158 			     sizeof_field(struct bpf_sock_ops_kern, replylong));
10159 		off = si->off;
10160 		off -= offsetof(struct bpf_sock_ops, replylong[0]);
10161 		off += offsetof(struct bpf_sock_ops_kern, replylong[0]);
10162 		if (type == BPF_WRITE)
10163 			*insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
10164 					      off);
10165 		else
10166 			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
10167 					      off);
10168 		break;
10169 
10170 	case offsetof(struct bpf_sock_ops, family):
10171 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
10172 
10173 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10174 					      struct bpf_sock_ops_kern, sk),
10175 				      si->dst_reg, si->src_reg,
10176 				      offsetof(struct bpf_sock_ops_kern, sk));
10177 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10178 				      offsetof(struct sock_common, skc_family));
10179 		break;
10180 
10181 	case offsetof(struct bpf_sock_ops, remote_ip4):
10182 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
10183 
10184 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10185 						struct bpf_sock_ops_kern, sk),
10186 				      si->dst_reg, si->src_reg,
10187 				      offsetof(struct bpf_sock_ops_kern, sk));
10188 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10189 				      offsetof(struct sock_common, skc_daddr));
10190 		break;
10191 
10192 	case offsetof(struct bpf_sock_ops, local_ip4):
10193 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10194 					  skc_rcv_saddr) != 4);
10195 
10196 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10197 					      struct bpf_sock_ops_kern, sk),
10198 				      si->dst_reg, si->src_reg,
10199 				      offsetof(struct bpf_sock_ops_kern, sk));
10200 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10201 				      offsetof(struct sock_common,
10202 					       skc_rcv_saddr));
10203 		break;
10204 
10205 	case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
10206 	     offsetof(struct bpf_sock_ops, remote_ip6[3]):
10207 #if IS_ENABLED(CONFIG_IPV6)
10208 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10209 					  skc_v6_daddr.s6_addr32[0]) != 4);
10210 
10211 		off = si->off;
10212 		off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
10213 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10214 						struct bpf_sock_ops_kern, sk),
10215 				      si->dst_reg, si->src_reg,
10216 				      offsetof(struct bpf_sock_ops_kern, sk));
10217 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10218 				      offsetof(struct sock_common,
10219 					       skc_v6_daddr.s6_addr32[0]) +
10220 				      off);
10221 #else
10222 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10223 #endif
10224 		break;
10225 
10226 	case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
10227 	     offsetof(struct bpf_sock_ops, local_ip6[3]):
10228 #if IS_ENABLED(CONFIG_IPV6)
10229 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10230 					  skc_v6_rcv_saddr.s6_addr32[0]) != 4);
10231 
10232 		off = si->off;
10233 		off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
10234 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10235 						struct bpf_sock_ops_kern, sk),
10236 				      si->dst_reg, si->src_reg,
10237 				      offsetof(struct bpf_sock_ops_kern, sk));
10238 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10239 				      offsetof(struct sock_common,
10240 					       skc_v6_rcv_saddr.s6_addr32[0]) +
10241 				      off);
10242 #else
10243 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10244 #endif
10245 		break;
10246 
10247 	case offsetof(struct bpf_sock_ops, remote_port):
10248 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
10249 
10250 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10251 						struct bpf_sock_ops_kern, sk),
10252 				      si->dst_reg, si->src_reg,
10253 				      offsetof(struct bpf_sock_ops_kern, sk));
10254 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10255 				      offsetof(struct sock_common, skc_dport));
10256 #ifndef __BIG_ENDIAN_BITFIELD
10257 		*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
10258 #endif
10259 		break;
10260 
10261 	case offsetof(struct bpf_sock_ops, local_port):
10262 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
10263 
10264 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10265 						struct bpf_sock_ops_kern, sk),
10266 				      si->dst_reg, si->src_reg,
10267 				      offsetof(struct bpf_sock_ops_kern, sk));
10268 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10269 				      offsetof(struct sock_common, skc_num));
10270 		break;
10271 
10272 	case offsetof(struct bpf_sock_ops, is_fullsock):
10273 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10274 						struct bpf_sock_ops_kern,
10275 						is_fullsock),
10276 				      si->dst_reg, si->src_reg,
10277 				      offsetof(struct bpf_sock_ops_kern,
10278 					       is_fullsock));
10279 		break;
10280 
10281 	case offsetof(struct bpf_sock_ops, state):
10282 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_state) != 1);
10283 
10284 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10285 						struct bpf_sock_ops_kern, sk),
10286 				      si->dst_reg, si->src_reg,
10287 				      offsetof(struct bpf_sock_ops_kern, sk));
10288 		*insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg,
10289 				      offsetof(struct sock_common, skc_state));
10290 		break;
10291 
10292 	case offsetof(struct bpf_sock_ops, rtt_min):
10293 		BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
10294 			     sizeof(struct minmax));
10295 		BUILD_BUG_ON(sizeof(struct minmax) <
10296 			     sizeof(struct minmax_sample));
10297 
10298 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10299 						struct bpf_sock_ops_kern, sk),
10300 				      si->dst_reg, si->src_reg,
10301 				      offsetof(struct bpf_sock_ops_kern, sk));
10302 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10303 				      offsetof(struct tcp_sock, rtt_min) +
10304 				      sizeof_field(struct minmax_sample, t));
10305 		break;
10306 
10307 	case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags):
10308 		SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags,
10309 				   struct tcp_sock);
10310 		break;
10311 
10312 	case offsetof(struct bpf_sock_ops, sk_txhash):
10313 		SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash,
10314 					  struct sock, type);
10315 		break;
10316 	case offsetof(struct bpf_sock_ops, snd_cwnd):
10317 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_cwnd);
10318 		break;
10319 	case offsetof(struct bpf_sock_ops, srtt_us):
10320 		SOCK_OPS_GET_TCP_SOCK_FIELD(srtt_us);
10321 		break;
10322 	case offsetof(struct bpf_sock_ops, snd_ssthresh):
10323 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_ssthresh);
10324 		break;
10325 	case offsetof(struct bpf_sock_ops, rcv_nxt):
10326 		SOCK_OPS_GET_TCP_SOCK_FIELD(rcv_nxt);
10327 		break;
10328 	case offsetof(struct bpf_sock_ops, snd_nxt):
10329 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_nxt);
10330 		break;
10331 	case offsetof(struct bpf_sock_ops, snd_una):
10332 		SOCK_OPS_GET_TCP_SOCK_FIELD(snd_una);
10333 		break;
10334 	case offsetof(struct bpf_sock_ops, mss_cache):
10335 		SOCK_OPS_GET_TCP_SOCK_FIELD(mss_cache);
10336 		break;
10337 	case offsetof(struct bpf_sock_ops, ecn_flags):
10338 		SOCK_OPS_GET_TCP_SOCK_FIELD(ecn_flags);
10339 		break;
10340 	case offsetof(struct bpf_sock_ops, rate_delivered):
10341 		SOCK_OPS_GET_TCP_SOCK_FIELD(rate_delivered);
10342 		break;
10343 	case offsetof(struct bpf_sock_ops, rate_interval_us):
10344 		SOCK_OPS_GET_TCP_SOCK_FIELD(rate_interval_us);
10345 		break;
10346 	case offsetof(struct bpf_sock_ops, packets_out):
10347 		SOCK_OPS_GET_TCP_SOCK_FIELD(packets_out);
10348 		break;
10349 	case offsetof(struct bpf_sock_ops, retrans_out):
10350 		SOCK_OPS_GET_TCP_SOCK_FIELD(retrans_out);
10351 		break;
10352 	case offsetof(struct bpf_sock_ops, total_retrans):
10353 		SOCK_OPS_GET_TCP_SOCK_FIELD(total_retrans);
10354 		break;
10355 	case offsetof(struct bpf_sock_ops, segs_in):
10356 		SOCK_OPS_GET_TCP_SOCK_FIELD(segs_in);
10357 		break;
10358 	case offsetof(struct bpf_sock_ops, data_segs_in):
10359 		SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_in);
10360 		break;
10361 	case offsetof(struct bpf_sock_ops, segs_out):
10362 		SOCK_OPS_GET_TCP_SOCK_FIELD(segs_out);
10363 		break;
10364 	case offsetof(struct bpf_sock_ops, data_segs_out):
10365 		SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_out);
10366 		break;
10367 	case offsetof(struct bpf_sock_ops, lost_out):
10368 		SOCK_OPS_GET_TCP_SOCK_FIELD(lost_out);
10369 		break;
10370 	case offsetof(struct bpf_sock_ops, sacked_out):
10371 		SOCK_OPS_GET_TCP_SOCK_FIELD(sacked_out);
10372 		break;
10373 	case offsetof(struct bpf_sock_ops, bytes_received):
10374 		SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_received);
10375 		break;
10376 	case offsetof(struct bpf_sock_ops, bytes_acked):
10377 		SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_acked);
10378 		break;
10379 	case offsetof(struct bpf_sock_ops, sk):
10380 		SOCK_OPS_GET_SK();
10381 		break;
10382 	case offsetof(struct bpf_sock_ops, skb_data_end):
10383 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10384 						       skb_data_end),
10385 				      si->dst_reg, si->src_reg,
10386 				      offsetof(struct bpf_sock_ops_kern,
10387 					       skb_data_end));
10388 		break;
10389 	case offsetof(struct bpf_sock_ops, skb_data):
10390 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10391 						       skb),
10392 				      si->dst_reg, si->src_reg,
10393 				      offsetof(struct bpf_sock_ops_kern,
10394 					       skb));
10395 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10396 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
10397 				      si->dst_reg, si->dst_reg,
10398 				      offsetof(struct sk_buff, data));
10399 		break;
10400 	case offsetof(struct bpf_sock_ops, skb_len):
10401 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10402 						       skb),
10403 				      si->dst_reg, si->src_reg,
10404 				      offsetof(struct bpf_sock_ops_kern,
10405 					       skb));
10406 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10407 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
10408 				      si->dst_reg, si->dst_reg,
10409 				      offsetof(struct sk_buff, len));
10410 		break;
10411 	case offsetof(struct bpf_sock_ops, skb_tcp_flags):
10412 		off = offsetof(struct sk_buff, cb);
10413 		off += offsetof(struct tcp_skb_cb, tcp_flags);
10414 		*target_size = sizeof_field(struct tcp_skb_cb, tcp_flags);
10415 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10416 						       skb),
10417 				      si->dst_reg, si->src_reg,
10418 				      offsetof(struct bpf_sock_ops_kern,
10419 					       skb));
10420 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10421 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_skb_cb,
10422 						       tcp_flags),
10423 				      si->dst_reg, si->dst_reg, off);
10424 		break;
10425 	}
10426 	return insn - insn_buf;
10427 }
10428 
10429 /* data_end = skb->data + skb_headlen() */
bpf_convert_data_end_access(const struct bpf_insn * si,struct bpf_insn * insn)10430 static struct bpf_insn *bpf_convert_data_end_access(const struct bpf_insn *si,
10431 						    struct bpf_insn *insn)
10432 {
10433 	int reg;
10434 	int temp_reg_off = offsetof(struct sk_buff, cb) +
10435 			   offsetof(struct sk_skb_cb, temp_reg);
10436 
10437 	if (si->src_reg == si->dst_reg) {
10438 		/* We need an extra register, choose and save a register. */
10439 		reg = BPF_REG_9;
10440 		if (si->src_reg == reg || si->dst_reg == reg)
10441 			reg--;
10442 		if (si->src_reg == reg || si->dst_reg == reg)
10443 			reg--;
10444 		*insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg, temp_reg_off);
10445 	} else {
10446 		reg = si->dst_reg;
10447 	}
10448 
10449 	/* reg = skb->data */
10450 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
10451 			      reg, si->src_reg,
10452 			      offsetof(struct sk_buff, data));
10453 	/* AX = skb->len */
10454 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
10455 			      BPF_REG_AX, si->src_reg,
10456 			      offsetof(struct sk_buff, len));
10457 	/* reg = skb->data + skb->len */
10458 	*insn++ = BPF_ALU64_REG(BPF_ADD, reg, BPF_REG_AX);
10459 	/* AX = skb->data_len */
10460 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data_len),
10461 			      BPF_REG_AX, si->src_reg,
10462 			      offsetof(struct sk_buff, data_len));
10463 
10464 	/* reg = skb->data + skb->len - skb->data_len */
10465 	*insn++ = BPF_ALU64_REG(BPF_SUB, reg, BPF_REG_AX);
10466 
10467 	if (si->src_reg == si->dst_reg) {
10468 		/* Restore the saved register */
10469 		*insn++ = BPF_MOV64_REG(BPF_REG_AX, si->src_reg);
10470 		*insn++ = BPF_MOV64_REG(si->dst_reg, reg);
10471 		*insn++ = BPF_LDX_MEM(BPF_DW, reg, BPF_REG_AX, temp_reg_off);
10472 	}
10473 
10474 	return insn;
10475 }
10476 
sk_skb_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10477 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
10478 				     const struct bpf_insn *si,
10479 				     struct bpf_insn *insn_buf,
10480 				     struct bpf_prog *prog, u32 *target_size)
10481 {
10482 	struct bpf_insn *insn = insn_buf;
10483 	int off;
10484 
10485 	switch (si->off) {
10486 	case offsetof(struct __sk_buff, data_end):
10487 		insn = bpf_convert_data_end_access(si, insn);
10488 		break;
10489 	case offsetof(struct __sk_buff, cb[0]) ...
10490 	     offsetofend(struct __sk_buff, cb[4]) - 1:
10491 		BUILD_BUG_ON(sizeof_field(struct sk_skb_cb, data) < 20);
10492 		BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
10493 			      offsetof(struct sk_skb_cb, data)) %
10494 			     sizeof(__u64));
10495 
10496 		prog->cb_access = 1;
10497 		off  = si->off;
10498 		off -= offsetof(struct __sk_buff, cb[0]);
10499 		off += offsetof(struct sk_buff, cb);
10500 		off += offsetof(struct sk_skb_cb, data);
10501 		if (type == BPF_WRITE)
10502 			*insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
10503 					      si->src_reg, off);
10504 		else
10505 			*insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
10506 					      si->src_reg, off);
10507 		break;
10508 
10509 
10510 	default:
10511 		return bpf_convert_ctx_access(type, si, insn_buf, prog,
10512 					      target_size);
10513 	}
10514 
10515 	return insn - insn_buf;
10516 }
10517 
sk_msg_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)10518 static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
10519 				     const struct bpf_insn *si,
10520 				     struct bpf_insn *insn_buf,
10521 				     struct bpf_prog *prog, u32 *target_size)
10522 {
10523 	struct bpf_insn *insn = insn_buf;
10524 #if IS_ENABLED(CONFIG_IPV6)
10525 	int off;
10526 #endif
10527 
10528 	/* convert ctx uses the fact sg element is first in struct */
10529 	BUILD_BUG_ON(offsetof(struct sk_msg, sg) != 0);
10530 
10531 	switch (si->off) {
10532 	case offsetof(struct sk_msg_md, data):
10533 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data),
10534 				      si->dst_reg, si->src_reg,
10535 				      offsetof(struct sk_msg, data));
10536 		break;
10537 	case offsetof(struct sk_msg_md, data_end):
10538 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data_end),
10539 				      si->dst_reg, si->src_reg,
10540 				      offsetof(struct sk_msg, data_end));
10541 		break;
10542 	case offsetof(struct sk_msg_md, family):
10543 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
10544 
10545 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10546 					      struct sk_msg, sk),
10547 				      si->dst_reg, si->src_reg,
10548 				      offsetof(struct sk_msg, sk));
10549 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10550 				      offsetof(struct sock_common, skc_family));
10551 		break;
10552 
10553 	case offsetof(struct sk_msg_md, remote_ip4):
10554 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
10555 
10556 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10557 						struct sk_msg, sk),
10558 				      si->dst_reg, si->src_reg,
10559 				      offsetof(struct sk_msg, sk));
10560 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10561 				      offsetof(struct sock_common, skc_daddr));
10562 		break;
10563 
10564 	case offsetof(struct sk_msg_md, local_ip4):
10565 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10566 					  skc_rcv_saddr) != 4);
10567 
10568 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10569 					      struct sk_msg, sk),
10570 				      si->dst_reg, si->src_reg,
10571 				      offsetof(struct sk_msg, sk));
10572 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10573 				      offsetof(struct sock_common,
10574 					       skc_rcv_saddr));
10575 		break;
10576 
10577 	case offsetof(struct sk_msg_md, remote_ip6[0]) ...
10578 	     offsetof(struct sk_msg_md, remote_ip6[3]):
10579 #if IS_ENABLED(CONFIG_IPV6)
10580 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10581 					  skc_v6_daddr.s6_addr32[0]) != 4);
10582 
10583 		off = si->off;
10584 		off -= offsetof(struct sk_msg_md, remote_ip6[0]);
10585 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10586 						struct sk_msg, sk),
10587 				      si->dst_reg, si->src_reg,
10588 				      offsetof(struct sk_msg, sk));
10589 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10590 				      offsetof(struct sock_common,
10591 					       skc_v6_daddr.s6_addr32[0]) +
10592 				      off);
10593 #else
10594 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10595 #endif
10596 		break;
10597 
10598 	case offsetof(struct sk_msg_md, local_ip6[0]) ...
10599 	     offsetof(struct sk_msg_md, local_ip6[3]):
10600 #if IS_ENABLED(CONFIG_IPV6)
10601 		BUILD_BUG_ON(sizeof_field(struct sock_common,
10602 					  skc_v6_rcv_saddr.s6_addr32[0]) != 4);
10603 
10604 		off = si->off;
10605 		off -= offsetof(struct sk_msg_md, local_ip6[0]);
10606 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10607 						struct sk_msg, sk),
10608 				      si->dst_reg, si->src_reg,
10609 				      offsetof(struct sk_msg, sk));
10610 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10611 				      offsetof(struct sock_common,
10612 					       skc_v6_rcv_saddr.s6_addr32[0]) +
10613 				      off);
10614 #else
10615 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10616 #endif
10617 		break;
10618 
10619 	case offsetof(struct sk_msg_md, remote_port):
10620 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
10621 
10622 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10623 						struct sk_msg, sk),
10624 				      si->dst_reg, si->src_reg,
10625 				      offsetof(struct sk_msg, sk));
10626 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10627 				      offsetof(struct sock_common, skc_dport));
10628 #ifndef __BIG_ENDIAN_BITFIELD
10629 		*insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
10630 #endif
10631 		break;
10632 
10633 	case offsetof(struct sk_msg_md, local_port):
10634 		BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
10635 
10636 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10637 						struct sk_msg, sk),
10638 				      si->dst_reg, si->src_reg,
10639 				      offsetof(struct sk_msg, sk));
10640 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10641 				      offsetof(struct sock_common, skc_num));
10642 		break;
10643 
10644 	case offsetof(struct sk_msg_md, size):
10645 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_sg, size),
10646 				      si->dst_reg, si->src_reg,
10647 				      offsetof(struct sk_msg_sg, size));
10648 		break;
10649 
10650 	case offsetof(struct sk_msg_md, sk):
10651 		*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, sk),
10652 				      si->dst_reg, si->src_reg,
10653 				      offsetof(struct sk_msg, sk));
10654 		break;
10655 	}
10656 
10657 	return insn - insn_buf;
10658 }
10659 
10660 const struct bpf_verifier_ops sk_filter_verifier_ops = {
10661 	.get_func_proto		= sk_filter_func_proto,
10662 	.is_valid_access	= sk_filter_is_valid_access,
10663 	.convert_ctx_access	= bpf_convert_ctx_access,
10664 	.gen_ld_abs		= bpf_gen_ld_abs,
10665 };
10666 
10667 const struct bpf_prog_ops sk_filter_prog_ops = {
10668 	.test_run		= bpf_prog_test_run_skb,
10669 };
10670 
10671 const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
10672 	.get_func_proto		= tc_cls_act_func_proto,
10673 	.is_valid_access	= tc_cls_act_is_valid_access,
10674 	.convert_ctx_access	= tc_cls_act_convert_ctx_access,
10675 	.gen_prologue		= tc_cls_act_prologue,
10676 	.gen_ld_abs		= bpf_gen_ld_abs,
10677 	.btf_struct_access	= tc_cls_act_btf_struct_access,
10678 };
10679 
10680 const struct bpf_prog_ops tc_cls_act_prog_ops = {
10681 	.test_run		= bpf_prog_test_run_skb,
10682 };
10683 
10684 const struct bpf_verifier_ops xdp_verifier_ops = {
10685 	.get_func_proto		= xdp_func_proto,
10686 	.is_valid_access	= xdp_is_valid_access,
10687 	.convert_ctx_access	= xdp_convert_ctx_access,
10688 	.gen_prologue		= bpf_noop_prologue,
10689 	.btf_struct_access	= xdp_btf_struct_access,
10690 };
10691 
10692 const struct bpf_prog_ops xdp_prog_ops = {
10693 	.test_run		= bpf_prog_test_run_xdp,
10694 };
10695 
10696 const struct bpf_verifier_ops cg_skb_verifier_ops = {
10697 	.get_func_proto		= cg_skb_func_proto,
10698 	.is_valid_access	= cg_skb_is_valid_access,
10699 	.convert_ctx_access	= bpf_convert_ctx_access,
10700 };
10701 
10702 const struct bpf_prog_ops cg_skb_prog_ops = {
10703 	.test_run		= bpf_prog_test_run_skb,
10704 };
10705 
10706 const struct bpf_verifier_ops lwt_in_verifier_ops = {
10707 	.get_func_proto		= lwt_in_func_proto,
10708 	.is_valid_access	= lwt_is_valid_access,
10709 	.convert_ctx_access	= bpf_convert_ctx_access,
10710 };
10711 
10712 const struct bpf_prog_ops lwt_in_prog_ops = {
10713 	.test_run		= bpf_prog_test_run_skb,
10714 };
10715 
10716 const struct bpf_verifier_ops lwt_out_verifier_ops = {
10717 	.get_func_proto		= lwt_out_func_proto,
10718 	.is_valid_access	= lwt_is_valid_access,
10719 	.convert_ctx_access	= bpf_convert_ctx_access,
10720 };
10721 
10722 const struct bpf_prog_ops lwt_out_prog_ops = {
10723 	.test_run		= bpf_prog_test_run_skb,
10724 };
10725 
10726 const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
10727 	.get_func_proto		= lwt_xmit_func_proto,
10728 	.is_valid_access	= lwt_is_valid_access,
10729 	.convert_ctx_access	= bpf_convert_ctx_access,
10730 	.gen_prologue		= tc_cls_act_prologue,
10731 };
10732 
10733 const struct bpf_prog_ops lwt_xmit_prog_ops = {
10734 	.test_run		= bpf_prog_test_run_skb,
10735 };
10736 
10737 const struct bpf_verifier_ops lwt_seg6local_verifier_ops = {
10738 	.get_func_proto		= lwt_seg6local_func_proto,
10739 	.is_valid_access	= lwt_is_valid_access,
10740 	.convert_ctx_access	= bpf_convert_ctx_access,
10741 };
10742 
10743 const struct bpf_prog_ops lwt_seg6local_prog_ops = {
10744 	.test_run		= bpf_prog_test_run_skb,
10745 };
10746 
10747 const struct bpf_verifier_ops cg_sock_verifier_ops = {
10748 	.get_func_proto		= sock_filter_func_proto,
10749 	.is_valid_access	= sock_filter_is_valid_access,
10750 	.convert_ctx_access	= bpf_sock_convert_ctx_access,
10751 };
10752 
10753 const struct bpf_prog_ops cg_sock_prog_ops = {
10754 };
10755 
10756 const struct bpf_verifier_ops cg_sock_addr_verifier_ops = {
10757 	.get_func_proto		= sock_addr_func_proto,
10758 	.is_valid_access	= sock_addr_is_valid_access,
10759 	.convert_ctx_access	= sock_addr_convert_ctx_access,
10760 };
10761 
10762 const struct bpf_prog_ops cg_sock_addr_prog_ops = {
10763 };
10764 
10765 const struct bpf_verifier_ops sock_ops_verifier_ops = {
10766 	.get_func_proto		= sock_ops_func_proto,
10767 	.is_valid_access	= sock_ops_is_valid_access,
10768 	.convert_ctx_access	= sock_ops_convert_ctx_access,
10769 };
10770 
10771 const struct bpf_prog_ops sock_ops_prog_ops = {
10772 };
10773 
10774 const struct bpf_verifier_ops sk_skb_verifier_ops = {
10775 	.get_func_proto		= sk_skb_func_proto,
10776 	.is_valid_access	= sk_skb_is_valid_access,
10777 	.convert_ctx_access	= sk_skb_convert_ctx_access,
10778 	.gen_prologue		= sk_skb_prologue,
10779 };
10780 
10781 const struct bpf_prog_ops sk_skb_prog_ops = {
10782 };
10783 
10784 const struct bpf_verifier_ops sk_msg_verifier_ops = {
10785 	.get_func_proto		= sk_msg_func_proto,
10786 	.is_valid_access	= sk_msg_is_valid_access,
10787 	.convert_ctx_access	= sk_msg_convert_ctx_access,
10788 	.gen_prologue		= bpf_noop_prologue,
10789 };
10790 
10791 const struct bpf_prog_ops sk_msg_prog_ops = {
10792 };
10793 
10794 const struct bpf_verifier_ops flow_dissector_verifier_ops = {
10795 	.get_func_proto		= flow_dissector_func_proto,
10796 	.is_valid_access	= flow_dissector_is_valid_access,
10797 	.convert_ctx_access	= flow_dissector_convert_ctx_access,
10798 };
10799 
10800 const struct bpf_prog_ops flow_dissector_prog_ops = {
10801 	.test_run		= bpf_prog_test_run_flow_dissector,
10802 };
10803 
sk_detach_filter(struct sock * sk)10804 int sk_detach_filter(struct sock *sk)
10805 {
10806 	int ret = -ENOENT;
10807 	struct sk_filter *filter;
10808 
10809 	if (sock_flag(sk, SOCK_FILTER_LOCKED))
10810 		return -EPERM;
10811 
10812 	filter = rcu_dereference_protected(sk->sk_filter,
10813 					   lockdep_sock_is_held(sk));
10814 	if (filter) {
10815 		RCU_INIT_POINTER(sk->sk_filter, NULL);
10816 		sk_filter_uncharge(sk, filter);
10817 		ret = 0;
10818 	}
10819 
10820 	return ret;
10821 }
10822 EXPORT_SYMBOL_GPL(sk_detach_filter);
10823 
sk_get_filter(struct sock * sk,sockptr_t optval,unsigned int len)10824 int sk_get_filter(struct sock *sk, sockptr_t optval, unsigned int len)
10825 {
10826 	struct sock_fprog_kern *fprog;
10827 	struct sk_filter *filter;
10828 	int ret = 0;
10829 
10830 	sockopt_lock_sock(sk);
10831 	filter = rcu_dereference_protected(sk->sk_filter,
10832 					   lockdep_sock_is_held(sk));
10833 	if (!filter)
10834 		goto out;
10835 
10836 	/* We're copying the filter that has been originally attached,
10837 	 * so no conversion/decode needed anymore. eBPF programs that
10838 	 * have no original program cannot be dumped through this.
10839 	 */
10840 	ret = -EACCES;
10841 	fprog = filter->prog->orig_prog;
10842 	if (!fprog)
10843 		goto out;
10844 
10845 	ret = fprog->len;
10846 	if (!len)
10847 		/* User space only enquires number of filter blocks. */
10848 		goto out;
10849 
10850 	ret = -EINVAL;
10851 	if (len < fprog->len)
10852 		goto out;
10853 
10854 	ret = -EFAULT;
10855 	if (copy_to_sockptr(optval, fprog->filter, bpf_classic_proglen(fprog)))
10856 		goto out;
10857 
10858 	/* Instead of bytes, the API requests to return the number
10859 	 * of filter blocks.
10860 	 */
10861 	ret = fprog->len;
10862 out:
10863 	sockopt_release_sock(sk);
10864 	return ret;
10865 }
10866 
10867 #ifdef CONFIG_INET
bpf_init_reuseport_kern(struct sk_reuseport_kern * reuse_kern,struct sock_reuseport * reuse,struct sock * sk,struct sk_buff * skb,struct sock * migrating_sk,u32 hash)10868 static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern,
10869 				    struct sock_reuseport *reuse,
10870 				    struct sock *sk, struct sk_buff *skb,
10871 				    struct sock *migrating_sk,
10872 				    u32 hash)
10873 {
10874 	reuse_kern->skb = skb;
10875 	reuse_kern->sk = sk;
10876 	reuse_kern->selected_sk = NULL;
10877 	reuse_kern->migrating_sk = migrating_sk;
10878 	reuse_kern->data_end = skb->data + skb_headlen(skb);
10879 	reuse_kern->hash = hash;
10880 	reuse_kern->reuseport_id = reuse->reuseport_id;
10881 	reuse_kern->bind_inany = reuse->bind_inany;
10882 }
10883 
bpf_run_sk_reuseport(struct sock_reuseport * reuse,struct sock * sk,struct bpf_prog * prog,struct sk_buff * skb,struct sock * migrating_sk,u32 hash)10884 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
10885 				  struct bpf_prog *prog, struct sk_buff *skb,
10886 				  struct sock *migrating_sk,
10887 				  u32 hash)
10888 {
10889 	struct sk_reuseport_kern reuse_kern;
10890 	enum sk_action action;
10891 
10892 	bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, migrating_sk, hash);
10893 	action = bpf_prog_run(prog, &reuse_kern);
10894 
10895 	if (action == SK_PASS)
10896 		return reuse_kern.selected_sk;
10897 	else
10898 		return ERR_PTR(-ECONNREFUSED);
10899 }
10900 
BPF_CALL_4(sk_select_reuseport,struct sk_reuseport_kern *,reuse_kern,struct bpf_map *,map,void *,key,u32,flags)10901 BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern,
10902 	   struct bpf_map *, map, void *, key, u32, flags)
10903 {
10904 	bool is_sockarray = map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY;
10905 	struct sock_reuseport *reuse;
10906 	struct sock *selected_sk;
10907 
10908 	selected_sk = map->ops->map_lookup_elem(map, key);
10909 	if (!selected_sk)
10910 		return -ENOENT;
10911 
10912 	reuse = rcu_dereference(selected_sk->sk_reuseport_cb);
10913 	if (!reuse) {
10914 		/* Lookup in sock_map can return TCP ESTABLISHED sockets. */
10915 		if (sk_is_refcounted(selected_sk))
10916 			sock_put(selected_sk);
10917 
10918 		/* reuseport_array has only sk with non NULL sk_reuseport_cb.
10919 		 * The only (!reuse) case here is - the sk has already been
10920 		 * unhashed (e.g. by close()), so treat it as -ENOENT.
10921 		 *
10922 		 * Other maps (e.g. sock_map) do not provide this guarantee and
10923 		 * the sk may never be in the reuseport group to begin with.
10924 		 */
10925 		return is_sockarray ? -ENOENT : -EINVAL;
10926 	}
10927 
10928 	if (unlikely(reuse->reuseport_id != reuse_kern->reuseport_id)) {
10929 		struct sock *sk = reuse_kern->sk;
10930 
10931 		if (sk->sk_protocol != selected_sk->sk_protocol)
10932 			return -EPROTOTYPE;
10933 		else if (sk->sk_family != selected_sk->sk_family)
10934 			return -EAFNOSUPPORT;
10935 
10936 		/* Catch all. Likely bound to a different sockaddr. */
10937 		return -EBADFD;
10938 	}
10939 
10940 	reuse_kern->selected_sk = selected_sk;
10941 
10942 	return 0;
10943 }
10944 
10945 static const struct bpf_func_proto sk_select_reuseport_proto = {
10946 	.func           = sk_select_reuseport,
10947 	.gpl_only       = false,
10948 	.ret_type       = RET_INTEGER,
10949 	.arg1_type	= ARG_PTR_TO_CTX,
10950 	.arg2_type      = ARG_CONST_MAP_PTR,
10951 	.arg3_type      = ARG_PTR_TO_MAP_KEY,
10952 	.arg4_type	= ARG_ANYTHING,
10953 };
10954 
BPF_CALL_4(sk_reuseport_load_bytes,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len)10955 BPF_CALL_4(sk_reuseport_load_bytes,
10956 	   const struct sk_reuseport_kern *, reuse_kern, u32, offset,
10957 	   void *, to, u32, len)
10958 {
10959 	return ____bpf_skb_load_bytes(reuse_kern->skb, offset, to, len);
10960 }
10961 
10962 static const struct bpf_func_proto sk_reuseport_load_bytes_proto = {
10963 	.func		= sk_reuseport_load_bytes,
10964 	.gpl_only	= false,
10965 	.ret_type	= RET_INTEGER,
10966 	.arg1_type	= ARG_PTR_TO_CTX,
10967 	.arg2_type	= ARG_ANYTHING,
10968 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
10969 	.arg4_type	= ARG_CONST_SIZE,
10970 };
10971 
BPF_CALL_5(sk_reuseport_load_bytes_relative,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len,u32,start_header)10972 BPF_CALL_5(sk_reuseport_load_bytes_relative,
10973 	   const struct sk_reuseport_kern *, reuse_kern, u32, offset,
10974 	   void *, to, u32, len, u32, start_header)
10975 {
10976 	return ____bpf_skb_load_bytes_relative(reuse_kern->skb, offset, to,
10977 					       len, start_header);
10978 }
10979 
10980 static const struct bpf_func_proto sk_reuseport_load_bytes_relative_proto = {
10981 	.func		= sk_reuseport_load_bytes_relative,
10982 	.gpl_only	= false,
10983 	.ret_type	= RET_INTEGER,
10984 	.arg1_type	= ARG_PTR_TO_CTX,
10985 	.arg2_type	= ARG_ANYTHING,
10986 	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
10987 	.arg4_type	= ARG_CONST_SIZE,
10988 	.arg5_type	= ARG_ANYTHING,
10989 };
10990 
10991 static const struct bpf_func_proto *
sk_reuseport_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)10992 sk_reuseport_func_proto(enum bpf_func_id func_id,
10993 			const struct bpf_prog *prog)
10994 {
10995 	switch (func_id) {
10996 	case BPF_FUNC_sk_select_reuseport:
10997 		return &sk_select_reuseport_proto;
10998 	case BPF_FUNC_skb_load_bytes:
10999 		return &sk_reuseport_load_bytes_proto;
11000 	case BPF_FUNC_skb_load_bytes_relative:
11001 		return &sk_reuseport_load_bytes_relative_proto;
11002 	case BPF_FUNC_get_socket_cookie:
11003 		return &bpf_get_socket_ptr_cookie_proto;
11004 	case BPF_FUNC_ktime_get_coarse_ns:
11005 		return &bpf_ktime_get_coarse_ns_proto;
11006 	default:
11007 		return bpf_base_func_proto(func_id);
11008 	}
11009 }
11010 
11011 static bool
sk_reuseport_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)11012 sk_reuseport_is_valid_access(int off, int size,
11013 			     enum bpf_access_type type,
11014 			     const struct bpf_prog *prog,
11015 			     struct bpf_insn_access_aux *info)
11016 {
11017 	const u32 size_default = sizeof(__u32);
11018 
11019 	if (off < 0 || off >= sizeof(struct sk_reuseport_md) ||
11020 	    off % size || type != BPF_READ)
11021 		return false;
11022 
11023 	switch (off) {
11024 	case offsetof(struct sk_reuseport_md, data):
11025 		info->reg_type = PTR_TO_PACKET;
11026 		return size == sizeof(__u64);
11027 
11028 	case offsetof(struct sk_reuseport_md, data_end):
11029 		info->reg_type = PTR_TO_PACKET_END;
11030 		return size == sizeof(__u64);
11031 
11032 	case offsetof(struct sk_reuseport_md, hash):
11033 		return size == size_default;
11034 
11035 	case offsetof(struct sk_reuseport_md, sk):
11036 		info->reg_type = PTR_TO_SOCKET;
11037 		return size == sizeof(__u64);
11038 
11039 	case offsetof(struct sk_reuseport_md, migrating_sk):
11040 		info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
11041 		return size == sizeof(__u64);
11042 
11043 	/* Fields that allow narrowing */
11044 	case bpf_ctx_range(struct sk_reuseport_md, eth_protocol):
11045 		if (size < sizeof_field(struct sk_buff, protocol))
11046 			return false;
11047 		fallthrough;
11048 	case bpf_ctx_range(struct sk_reuseport_md, ip_protocol):
11049 	case bpf_ctx_range(struct sk_reuseport_md, bind_inany):
11050 	case bpf_ctx_range(struct sk_reuseport_md, len):
11051 		bpf_ctx_record_field_size(info, size_default);
11052 		return bpf_ctx_narrow_access_ok(off, size, size_default);
11053 
11054 	default:
11055 		return false;
11056 	}
11057 }
11058 
11059 #define SK_REUSEPORT_LOAD_FIELD(F) ({					\
11060 	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_reuseport_kern, F), \
11061 			      si->dst_reg, si->src_reg,			\
11062 			      bpf_target_off(struct sk_reuseport_kern, F, \
11063 					     sizeof_field(struct sk_reuseport_kern, F), \
11064 					     target_size));		\
11065 	})
11066 
11067 #define SK_REUSEPORT_LOAD_SKB_FIELD(SKB_FIELD)				\
11068 	SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern,		\
11069 				    struct sk_buff,			\
11070 				    skb,				\
11071 				    SKB_FIELD)
11072 
11073 #define SK_REUSEPORT_LOAD_SK_FIELD(SK_FIELD)				\
11074 	SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern,		\
11075 				    struct sock,			\
11076 				    sk,					\
11077 				    SK_FIELD)
11078 
sk_reuseport_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)11079 static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type,
11080 					   const struct bpf_insn *si,
11081 					   struct bpf_insn *insn_buf,
11082 					   struct bpf_prog *prog,
11083 					   u32 *target_size)
11084 {
11085 	struct bpf_insn *insn = insn_buf;
11086 
11087 	switch (si->off) {
11088 	case offsetof(struct sk_reuseport_md, data):
11089 		SK_REUSEPORT_LOAD_SKB_FIELD(data);
11090 		break;
11091 
11092 	case offsetof(struct sk_reuseport_md, len):
11093 		SK_REUSEPORT_LOAD_SKB_FIELD(len);
11094 		break;
11095 
11096 	case offsetof(struct sk_reuseport_md, eth_protocol):
11097 		SK_REUSEPORT_LOAD_SKB_FIELD(protocol);
11098 		break;
11099 
11100 	case offsetof(struct sk_reuseport_md, ip_protocol):
11101 		SK_REUSEPORT_LOAD_SK_FIELD(sk_protocol);
11102 		break;
11103 
11104 	case offsetof(struct sk_reuseport_md, data_end):
11105 		SK_REUSEPORT_LOAD_FIELD(data_end);
11106 		break;
11107 
11108 	case offsetof(struct sk_reuseport_md, hash):
11109 		SK_REUSEPORT_LOAD_FIELD(hash);
11110 		break;
11111 
11112 	case offsetof(struct sk_reuseport_md, bind_inany):
11113 		SK_REUSEPORT_LOAD_FIELD(bind_inany);
11114 		break;
11115 
11116 	case offsetof(struct sk_reuseport_md, sk):
11117 		SK_REUSEPORT_LOAD_FIELD(sk);
11118 		break;
11119 
11120 	case offsetof(struct sk_reuseport_md, migrating_sk):
11121 		SK_REUSEPORT_LOAD_FIELD(migrating_sk);
11122 		break;
11123 	}
11124 
11125 	return insn - insn_buf;
11126 }
11127 
11128 const struct bpf_verifier_ops sk_reuseport_verifier_ops = {
11129 	.get_func_proto		= sk_reuseport_func_proto,
11130 	.is_valid_access	= sk_reuseport_is_valid_access,
11131 	.convert_ctx_access	= sk_reuseport_convert_ctx_access,
11132 };
11133 
11134 const struct bpf_prog_ops sk_reuseport_prog_ops = {
11135 };
11136 
11137 DEFINE_STATIC_KEY_FALSE(bpf_sk_lookup_enabled);
11138 EXPORT_SYMBOL(bpf_sk_lookup_enabled);
11139 
BPF_CALL_3(bpf_sk_lookup_assign,struct bpf_sk_lookup_kern *,ctx,struct sock *,sk,u64,flags)11140 BPF_CALL_3(bpf_sk_lookup_assign, struct bpf_sk_lookup_kern *, ctx,
11141 	   struct sock *, sk, u64, flags)
11142 {
11143 	if (unlikely(flags & ~(BPF_SK_LOOKUP_F_REPLACE |
11144 			       BPF_SK_LOOKUP_F_NO_REUSEPORT)))
11145 		return -EINVAL;
11146 	if (unlikely(sk && sk_is_refcounted(sk)))
11147 		return -ESOCKTNOSUPPORT; /* reject non-RCU freed sockets */
11148 	if (unlikely(sk && sk_is_tcp(sk) && sk->sk_state != TCP_LISTEN))
11149 		return -ESOCKTNOSUPPORT; /* only accept TCP socket in LISTEN */
11150 	if (unlikely(sk && sk_is_udp(sk) && sk->sk_state != TCP_CLOSE))
11151 		return -ESOCKTNOSUPPORT; /* only accept UDP socket in CLOSE */
11152 
11153 	/* Check if socket is suitable for packet L3/L4 protocol */
11154 	if (sk && sk->sk_protocol != ctx->protocol)
11155 		return -EPROTOTYPE;
11156 	if (sk && sk->sk_family != ctx->family &&
11157 	    (sk->sk_family == AF_INET || ipv6_only_sock(sk)))
11158 		return -EAFNOSUPPORT;
11159 
11160 	if (ctx->selected_sk && !(flags & BPF_SK_LOOKUP_F_REPLACE))
11161 		return -EEXIST;
11162 
11163 	/* Select socket as lookup result */
11164 	ctx->selected_sk = sk;
11165 	ctx->no_reuseport = flags & BPF_SK_LOOKUP_F_NO_REUSEPORT;
11166 	return 0;
11167 }
11168 
11169 static const struct bpf_func_proto bpf_sk_lookup_assign_proto = {
11170 	.func		= bpf_sk_lookup_assign,
11171 	.gpl_only	= false,
11172 	.ret_type	= RET_INTEGER,
11173 	.arg1_type	= ARG_PTR_TO_CTX,
11174 	.arg2_type	= ARG_PTR_TO_SOCKET_OR_NULL,
11175 	.arg3_type	= ARG_ANYTHING,
11176 };
11177 
11178 static const struct bpf_func_proto *
sk_lookup_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)11179 sk_lookup_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
11180 {
11181 	switch (func_id) {
11182 	case BPF_FUNC_perf_event_output:
11183 		return &bpf_event_output_data_proto;
11184 	case BPF_FUNC_sk_assign:
11185 		return &bpf_sk_lookup_assign_proto;
11186 	case BPF_FUNC_sk_release:
11187 		return &bpf_sk_release_proto;
11188 	default:
11189 		return bpf_sk_base_func_proto(func_id);
11190 	}
11191 }
11192 
sk_lookup_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)11193 static bool sk_lookup_is_valid_access(int off, int size,
11194 				      enum bpf_access_type type,
11195 				      const struct bpf_prog *prog,
11196 				      struct bpf_insn_access_aux *info)
11197 {
11198 	if (off < 0 || off >= sizeof(struct bpf_sk_lookup))
11199 		return false;
11200 	if (off % size != 0)
11201 		return false;
11202 	if (type != BPF_READ)
11203 		return false;
11204 
11205 	switch (off) {
11206 	case offsetof(struct bpf_sk_lookup, sk):
11207 		info->reg_type = PTR_TO_SOCKET_OR_NULL;
11208 		return size == sizeof(__u64);
11209 
11210 	case bpf_ctx_range(struct bpf_sk_lookup, family):
11211 	case bpf_ctx_range(struct bpf_sk_lookup, protocol):
11212 	case bpf_ctx_range(struct bpf_sk_lookup, remote_ip4):
11213 	case bpf_ctx_range(struct bpf_sk_lookup, local_ip4):
11214 	case bpf_ctx_range_till(struct bpf_sk_lookup, remote_ip6[0], remote_ip6[3]):
11215 	case bpf_ctx_range_till(struct bpf_sk_lookup, local_ip6[0], local_ip6[3]):
11216 	case bpf_ctx_range(struct bpf_sk_lookup, local_port):
11217 	case bpf_ctx_range(struct bpf_sk_lookup, ingress_ifindex):
11218 		bpf_ctx_record_field_size(info, sizeof(__u32));
11219 		return bpf_ctx_narrow_access_ok(off, size, sizeof(__u32));
11220 
11221 	case bpf_ctx_range(struct bpf_sk_lookup, remote_port):
11222 		/* Allow 4-byte access to 2-byte field for backward compatibility */
11223 		if (size == sizeof(__u32))
11224 			return true;
11225 		bpf_ctx_record_field_size(info, sizeof(__be16));
11226 		return bpf_ctx_narrow_access_ok(off, size, sizeof(__be16));
11227 
11228 	case offsetofend(struct bpf_sk_lookup, remote_port) ...
11229 	     offsetof(struct bpf_sk_lookup, local_ip4) - 1:
11230 		/* Allow access to zero padding for backward compatibility */
11231 		bpf_ctx_record_field_size(info, sizeof(__u16));
11232 		return bpf_ctx_narrow_access_ok(off, size, sizeof(__u16));
11233 
11234 	default:
11235 		return false;
11236 	}
11237 }
11238 
sk_lookup_convert_ctx_access(enum bpf_access_type type,const struct bpf_insn * si,struct bpf_insn * insn_buf,struct bpf_prog * prog,u32 * target_size)11239 static u32 sk_lookup_convert_ctx_access(enum bpf_access_type type,
11240 					const struct bpf_insn *si,
11241 					struct bpf_insn *insn_buf,
11242 					struct bpf_prog *prog,
11243 					u32 *target_size)
11244 {
11245 	struct bpf_insn *insn = insn_buf;
11246 
11247 	switch (si->off) {
11248 	case offsetof(struct bpf_sk_lookup, sk):
11249 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11250 				      offsetof(struct bpf_sk_lookup_kern, selected_sk));
11251 		break;
11252 
11253 	case offsetof(struct bpf_sk_lookup, family):
11254 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11255 				      bpf_target_off(struct bpf_sk_lookup_kern,
11256 						     family, 2, target_size));
11257 		break;
11258 
11259 	case offsetof(struct bpf_sk_lookup, protocol):
11260 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11261 				      bpf_target_off(struct bpf_sk_lookup_kern,
11262 						     protocol, 2, target_size));
11263 		break;
11264 
11265 	case offsetof(struct bpf_sk_lookup, remote_ip4):
11266 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11267 				      bpf_target_off(struct bpf_sk_lookup_kern,
11268 						     v4.saddr, 4, target_size));
11269 		break;
11270 
11271 	case offsetof(struct bpf_sk_lookup, local_ip4):
11272 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11273 				      bpf_target_off(struct bpf_sk_lookup_kern,
11274 						     v4.daddr, 4, target_size));
11275 		break;
11276 
11277 	case bpf_ctx_range_till(struct bpf_sk_lookup,
11278 				remote_ip6[0], remote_ip6[3]): {
11279 #if IS_ENABLED(CONFIG_IPV6)
11280 		int off = si->off;
11281 
11282 		off -= offsetof(struct bpf_sk_lookup, remote_ip6[0]);
11283 		off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
11284 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11285 				      offsetof(struct bpf_sk_lookup_kern, v6.saddr));
11286 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
11287 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
11288 #else
11289 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11290 #endif
11291 		break;
11292 	}
11293 	case bpf_ctx_range_till(struct bpf_sk_lookup,
11294 				local_ip6[0], local_ip6[3]): {
11295 #if IS_ENABLED(CONFIG_IPV6)
11296 		int off = si->off;
11297 
11298 		off -= offsetof(struct bpf_sk_lookup, local_ip6[0]);
11299 		off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
11300 		*insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11301 				      offsetof(struct bpf_sk_lookup_kern, v6.daddr));
11302 		*insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
11303 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
11304 #else
11305 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11306 #endif
11307 		break;
11308 	}
11309 	case offsetof(struct bpf_sk_lookup, remote_port):
11310 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11311 				      bpf_target_off(struct bpf_sk_lookup_kern,
11312 						     sport, 2, target_size));
11313 		break;
11314 
11315 	case offsetofend(struct bpf_sk_lookup, remote_port):
11316 		*target_size = 2;
11317 		*insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11318 		break;
11319 
11320 	case offsetof(struct bpf_sk_lookup, local_port):
11321 		*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11322 				      bpf_target_off(struct bpf_sk_lookup_kern,
11323 						     dport, 2, target_size));
11324 		break;
11325 
11326 	case offsetof(struct bpf_sk_lookup, ingress_ifindex):
11327 		*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11328 				      bpf_target_off(struct bpf_sk_lookup_kern,
11329 						     ingress_ifindex, 4, target_size));
11330 		break;
11331 	}
11332 
11333 	return insn - insn_buf;
11334 }
11335 
11336 const struct bpf_prog_ops sk_lookup_prog_ops = {
11337 	.test_run = bpf_prog_test_run_sk_lookup,
11338 };
11339 
11340 const struct bpf_verifier_ops sk_lookup_verifier_ops = {
11341 	.get_func_proto		= sk_lookup_func_proto,
11342 	.is_valid_access	= sk_lookup_is_valid_access,
11343 	.convert_ctx_access	= sk_lookup_convert_ctx_access,
11344 };
11345 
11346 #endif /* CONFIG_INET */
11347 
DEFINE_BPF_DISPATCHER(xdp)11348 DEFINE_BPF_DISPATCHER(xdp)
11349 
11350 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog)
11351 {
11352 	bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(xdp), prev_prog, prog);
11353 }
11354 
BTF_ID_LIST_GLOBAL(btf_sock_ids,MAX_BTF_SOCK_TYPE)11355 BTF_ID_LIST_GLOBAL(btf_sock_ids, MAX_BTF_SOCK_TYPE)
11356 #define BTF_SOCK_TYPE(name, type) BTF_ID(struct, type)
11357 BTF_SOCK_TYPE_xxx
11358 #undef BTF_SOCK_TYPE
11359 
11360 BPF_CALL_1(bpf_skc_to_tcp6_sock, struct sock *, sk)
11361 {
11362 	/* tcp6_sock type is not generated in dwarf and hence btf,
11363 	 * trigger an explicit type generation here.
11364 	 */
11365 	BTF_TYPE_EMIT(struct tcp6_sock);
11366 	if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP &&
11367 	    sk->sk_family == AF_INET6)
11368 		return (unsigned long)sk;
11369 
11370 	return (unsigned long)NULL;
11371 }
11372 
11373 const struct bpf_func_proto bpf_skc_to_tcp6_sock_proto = {
11374 	.func			= bpf_skc_to_tcp6_sock,
11375 	.gpl_only		= false,
11376 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11377 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11378 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP6],
11379 };
11380 
BPF_CALL_1(bpf_skc_to_tcp_sock,struct sock *,sk)11381 BPF_CALL_1(bpf_skc_to_tcp_sock, struct sock *, sk)
11382 {
11383 	if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
11384 		return (unsigned long)sk;
11385 
11386 	return (unsigned long)NULL;
11387 }
11388 
11389 const struct bpf_func_proto bpf_skc_to_tcp_sock_proto = {
11390 	.func			= bpf_skc_to_tcp_sock,
11391 	.gpl_only		= false,
11392 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11393 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11394 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP],
11395 };
11396 
BPF_CALL_1(bpf_skc_to_tcp_timewait_sock,struct sock *,sk)11397 BPF_CALL_1(bpf_skc_to_tcp_timewait_sock, struct sock *, sk)
11398 {
11399 	/* BTF types for tcp_timewait_sock and inet_timewait_sock are not
11400 	 * generated if CONFIG_INET=n. Trigger an explicit generation here.
11401 	 */
11402 	BTF_TYPE_EMIT(struct inet_timewait_sock);
11403 	BTF_TYPE_EMIT(struct tcp_timewait_sock);
11404 
11405 #ifdef CONFIG_INET
11406 	if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_TIME_WAIT)
11407 		return (unsigned long)sk;
11408 #endif
11409 
11410 #if IS_BUILTIN(CONFIG_IPV6)
11411 	if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_TIME_WAIT)
11412 		return (unsigned long)sk;
11413 #endif
11414 
11415 	return (unsigned long)NULL;
11416 }
11417 
11418 const struct bpf_func_proto bpf_skc_to_tcp_timewait_sock_proto = {
11419 	.func			= bpf_skc_to_tcp_timewait_sock,
11420 	.gpl_only		= false,
11421 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11422 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11423 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP_TW],
11424 };
11425 
BPF_CALL_1(bpf_skc_to_tcp_request_sock,struct sock *,sk)11426 BPF_CALL_1(bpf_skc_to_tcp_request_sock, struct sock *, sk)
11427 {
11428 #ifdef CONFIG_INET
11429 	if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_NEW_SYN_RECV)
11430 		return (unsigned long)sk;
11431 #endif
11432 
11433 #if IS_BUILTIN(CONFIG_IPV6)
11434 	if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_NEW_SYN_RECV)
11435 		return (unsigned long)sk;
11436 #endif
11437 
11438 	return (unsigned long)NULL;
11439 }
11440 
11441 const struct bpf_func_proto bpf_skc_to_tcp_request_sock_proto = {
11442 	.func			= bpf_skc_to_tcp_request_sock,
11443 	.gpl_only		= false,
11444 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11445 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11446 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_TCP_REQ],
11447 };
11448 
BPF_CALL_1(bpf_skc_to_udp6_sock,struct sock *,sk)11449 BPF_CALL_1(bpf_skc_to_udp6_sock, struct sock *, sk)
11450 {
11451 	/* udp6_sock type is not generated in dwarf and hence btf,
11452 	 * trigger an explicit type generation here.
11453 	 */
11454 	BTF_TYPE_EMIT(struct udp6_sock);
11455 	if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_UDP &&
11456 	    sk->sk_type == SOCK_DGRAM && sk->sk_family == AF_INET6)
11457 		return (unsigned long)sk;
11458 
11459 	return (unsigned long)NULL;
11460 }
11461 
11462 const struct bpf_func_proto bpf_skc_to_udp6_sock_proto = {
11463 	.func			= bpf_skc_to_udp6_sock,
11464 	.gpl_only		= false,
11465 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11466 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11467 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_UDP6],
11468 };
11469 
BPF_CALL_1(bpf_skc_to_unix_sock,struct sock *,sk)11470 BPF_CALL_1(bpf_skc_to_unix_sock, struct sock *, sk)
11471 {
11472 	/* unix_sock type is not generated in dwarf and hence btf,
11473 	 * trigger an explicit type generation here.
11474 	 */
11475 	BTF_TYPE_EMIT(struct unix_sock);
11476 	if (sk && sk_fullsock(sk) && sk->sk_family == AF_UNIX)
11477 		return (unsigned long)sk;
11478 
11479 	return (unsigned long)NULL;
11480 }
11481 
11482 const struct bpf_func_proto bpf_skc_to_unix_sock_proto = {
11483 	.func			= bpf_skc_to_unix_sock,
11484 	.gpl_only		= false,
11485 	.ret_type		= RET_PTR_TO_BTF_ID_OR_NULL,
11486 	.arg1_type		= ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11487 	.ret_btf_id		= &btf_sock_ids[BTF_SOCK_TYPE_UNIX],
11488 };
11489 
BPF_CALL_1(bpf_skc_to_mptcp_sock,struct sock *,sk)11490 BPF_CALL_1(bpf_skc_to_mptcp_sock, struct sock *, sk)
11491 {
11492 	BTF_TYPE_EMIT(struct mptcp_sock);
11493 	return (unsigned long)bpf_mptcp_sock_from_subflow(sk);
11494 }
11495 
11496 const struct bpf_func_proto bpf_skc_to_mptcp_sock_proto = {
11497 	.func		= bpf_skc_to_mptcp_sock,
11498 	.gpl_only	= false,
11499 	.ret_type	= RET_PTR_TO_BTF_ID_OR_NULL,
11500 	.arg1_type	= ARG_PTR_TO_SOCK_COMMON,
11501 	.ret_btf_id	= &btf_sock_ids[BTF_SOCK_TYPE_MPTCP],
11502 };
11503 
BPF_CALL_1(bpf_sock_from_file,struct file *,file)11504 BPF_CALL_1(bpf_sock_from_file, struct file *, file)
11505 {
11506 	return (unsigned long)sock_from_file(file);
11507 }
11508 
11509 BTF_ID_LIST(bpf_sock_from_file_btf_ids)
11510 BTF_ID(struct, socket)
11511 BTF_ID(struct, file)
11512 
11513 const struct bpf_func_proto bpf_sock_from_file_proto = {
11514 	.func		= bpf_sock_from_file,
11515 	.gpl_only	= false,
11516 	.ret_type	= RET_PTR_TO_BTF_ID_OR_NULL,
11517 	.ret_btf_id	= &bpf_sock_from_file_btf_ids[0],
11518 	.arg1_type	= ARG_PTR_TO_BTF_ID,
11519 	.arg1_btf_id	= &bpf_sock_from_file_btf_ids[1],
11520 };
11521 
11522 static const struct bpf_func_proto *
bpf_sk_base_func_proto(enum bpf_func_id func_id)11523 bpf_sk_base_func_proto(enum bpf_func_id func_id)
11524 {
11525 	const struct bpf_func_proto *func;
11526 
11527 	switch (func_id) {
11528 	case BPF_FUNC_skc_to_tcp6_sock:
11529 		func = &bpf_skc_to_tcp6_sock_proto;
11530 		break;
11531 	case BPF_FUNC_skc_to_tcp_sock:
11532 		func = &bpf_skc_to_tcp_sock_proto;
11533 		break;
11534 	case BPF_FUNC_skc_to_tcp_timewait_sock:
11535 		func = &bpf_skc_to_tcp_timewait_sock_proto;
11536 		break;
11537 	case BPF_FUNC_skc_to_tcp_request_sock:
11538 		func = &bpf_skc_to_tcp_request_sock_proto;
11539 		break;
11540 	case BPF_FUNC_skc_to_udp6_sock:
11541 		func = &bpf_skc_to_udp6_sock_proto;
11542 		break;
11543 	case BPF_FUNC_skc_to_unix_sock:
11544 		func = &bpf_skc_to_unix_sock_proto;
11545 		break;
11546 	case BPF_FUNC_skc_to_mptcp_sock:
11547 		func = &bpf_skc_to_mptcp_sock_proto;
11548 		break;
11549 	case BPF_FUNC_ktime_get_coarse_ns:
11550 		return &bpf_ktime_get_coarse_ns_proto;
11551 	default:
11552 		return bpf_base_func_proto(func_id);
11553 	}
11554 
11555 	if (!perfmon_capable())
11556 		return NULL;
11557 
11558 	return func;
11559 }
11560