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/module.h>
22 #include <linux/types.h>
23 #include <linux/mm.h>
24 #include <linux/fcntl.h>
25 #include <linux/socket.h>
26 #include <linux/sock_diag.h>
27 #include <linux/in.h>
28 #include <linux/inet.h>
29 #include <linux/netdevice.h>
30 #include <linux/if_packet.h>
31 #include <linux/if_arp.h>
32 #include <linux/gfp.h>
33 #include <net/inet_common.h>
34 #include <net/ip.h>
35 #include <net/protocol.h>
36 #include <net/netlink.h>
37 #include <linux/skbuff.h>
38 #include <linux/skmsg.h>
39 #include <net/sock.h>
40 #include <net/flow_dissector.h>
41 #include <linux/errno.h>
42 #include <linux/timer.h>
43 #include <linux/uaccess.h>
44 #include <asm/unaligned.h>
45 #include <linux/filter.h>
46 #include <linux/ratelimit.h>
47 #include <linux/seccomp.h>
48 #include <linux/if_vlan.h>
49 #include <linux/bpf.h>
50 #include <linux/btf.h>
51 #include <net/sch_generic.h>
52 #include <net/cls_cgroup.h>
53 #include <net/dst_metadata.h>
54 #include <net/dst.h>
55 #include <net/sock_reuseport.h>
56 #include <net/busy_poll.h>
57 #include <net/tcp.h>
58 #include <net/xfrm.h>
59 #include <net/udp.h>
60 #include <linux/bpf_trace.h>
61 #include <net/xdp_sock.h>
62 #include <linux/inetdevice.h>
63 #include <net/inet_hashtables.h>
64 #include <net/inet6_hashtables.h>
65 #include <net/ip_fib.h>
66 #include <net/nexthop.h>
67 #include <net/flow.h>
68 #include <net/arp.h>
69 #include <net/ipv6.h>
70 #include <net/net_namespace.h>
71 #include <linux/seg6_local.h>
72 #include <net/seg6.h>
73 #include <net/seg6_local.h>
74 #include <net/lwtunnel.h>
75 #include <net/ipv6_stubs.h>
76 #include <net/bpf_sk_storage.h>
77 #include <net/transp_v6.h>
78 #include <linux/btf_ids.h>
79 #include <net/tls.h>
80 #include <net/xdp.h>
81 #include <net/mptcp.h>
82
83 static const struct bpf_func_proto *
84 bpf_sk_base_func_proto(enum bpf_func_id func_id);
85
copy_bpf_fprog_from_user(struct sock_fprog * dst,sockptr_t src,int len)86 int copy_bpf_fprog_from_user(struct sock_fprog *dst, sockptr_t src, int len)
87 {
88 if (in_compat_syscall()) {
89 struct compat_sock_fprog f32;
90
91 if (len != sizeof(f32))
92 return -EINVAL;
93 if (copy_from_sockptr(&f32, src, sizeof(f32)))
94 return -EFAULT;
95 memset(dst, 0, sizeof(*dst));
96 dst->len = f32.len;
97 dst->filter = compat_ptr(f32.filter);
98 } else {
99 if (len != sizeof(*dst))
100 return -EINVAL;
101 if (copy_from_sockptr(dst, src, sizeof(*dst)))
102 return -EFAULT;
103 }
104
105 return 0;
106 }
107 EXPORT_SYMBOL_GPL(copy_bpf_fprog_from_user);
108
109 /**
110 * sk_filter_trim_cap - run a packet through a socket filter
111 * @sk: sock associated with &sk_buff
112 * @skb: buffer to filter
113 * @cap: limit on how short the eBPF program may trim the packet
114 *
115 * Run the eBPF program and then cut skb->data to correct size returned by
116 * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
117 * than pkt_len we keep whole skb->data. This is the socket level
118 * wrapper to bpf_prog_run. It returns 0 if the packet should
119 * be accepted or -EPERM if the packet should be tossed.
120 *
121 */
sk_filter_trim_cap(struct sock * sk,struct sk_buff * skb,unsigned int cap)122 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
123 {
124 int err;
125 struct sk_filter *filter;
126
127 /*
128 * If the skb was allocated from pfmemalloc reserves, only
129 * allow SOCK_MEMALLOC sockets to use it as this socket is
130 * helping free memory
131 */
132 if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
133 NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
134 return -ENOMEM;
135 }
136 err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
137 if (err)
138 return err;
139
140 err = security_sock_rcv_skb(sk, skb);
141 if (err)
142 return err;
143
144 rcu_read_lock();
145 filter = rcu_dereference(sk->sk_filter);
146 if (filter) {
147 struct sock *save_sk = skb->sk;
148 unsigned int pkt_len;
149
150 skb->sk = sk;
151 pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
152 skb->sk = save_sk;
153 err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
154 }
155 rcu_read_unlock();
156
157 return err;
158 }
159 EXPORT_SYMBOL(sk_filter_trim_cap);
160
BPF_CALL_1(bpf_skb_get_pay_offset,struct sk_buff *,skb)161 BPF_CALL_1(bpf_skb_get_pay_offset, struct sk_buff *, skb)
162 {
163 return skb_get_poff(skb);
164 }
165
BPF_CALL_3(bpf_skb_get_nlattr,struct sk_buff *,skb,u32,a,u32,x)166 BPF_CALL_3(bpf_skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
167 {
168 struct nlattr *nla;
169
170 if (skb_is_nonlinear(skb))
171 return 0;
172
173 if (skb->len < sizeof(struct nlattr))
174 return 0;
175
176 if (a > skb->len - sizeof(struct nlattr))
177 return 0;
178
179 nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
180 if (nla)
181 return (void *) nla - (void *) skb->data;
182
183 return 0;
184 }
185
BPF_CALL_3(bpf_skb_get_nlattr_nest,struct sk_buff *,skb,u32,a,u32,x)186 BPF_CALL_3(bpf_skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
187 {
188 struct nlattr *nla;
189
190 if (skb_is_nonlinear(skb))
191 return 0;
192
193 if (skb->len < sizeof(struct nlattr))
194 return 0;
195
196 if (a > skb->len - sizeof(struct nlattr))
197 return 0;
198
199 nla = (struct nlattr *) &skb->data[a];
200 if (nla->nla_len > skb->len - a)
201 return 0;
202
203 nla = nla_find_nested(nla, x);
204 if (nla)
205 return (void *) nla - (void *) skb->data;
206
207 return 0;
208 }
209
BPF_CALL_4(bpf_skb_load_helper_8,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)210 BPF_CALL_4(bpf_skb_load_helper_8, const struct sk_buff *, skb, const void *,
211 data, int, headlen, int, offset)
212 {
213 u8 tmp, *ptr;
214 const int len = sizeof(tmp);
215
216 if (offset >= 0) {
217 if (headlen - offset >= len)
218 return *(u8 *)(data + offset);
219 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
220 return tmp;
221 } else {
222 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
223 if (likely(ptr))
224 return *(u8 *)ptr;
225 }
226
227 return -EFAULT;
228 }
229
BPF_CALL_2(bpf_skb_load_helper_8_no_cache,const struct sk_buff *,skb,int,offset)230 BPF_CALL_2(bpf_skb_load_helper_8_no_cache, const struct sk_buff *, skb,
231 int, offset)
232 {
233 return ____bpf_skb_load_helper_8(skb, skb->data, skb->len - skb->data_len,
234 offset);
235 }
236
BPF_CALL_4(bpf_skb_load_helper_16,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)237 BPF_CALL_4(bpf_skb_load_helper_16, const struct sk_buff *, skb, const void *,
238 data, int, headlen, int, offset)
239 {
240 u16 tmp, *ptr;
241 const int len = sizeof(tmp);
242
243 if (offset >= 0) {
244 if (headlen - offset >= len)
245 return get_unaligned_be16(data + offset);
246 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
247 return be16_to_cpu(tmp);
248 } else {
249 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
250 if (likely(ptr))
251 return get_unaligned_be16(ptr);
252 }
253
254 return -EFAULT;
255 }
256
BPF_CALL_2(bpf_skb_load_helper_16_no_cache,const struct sk_buff *,skb,int,offset)257 BPF_CALL_2(bpf_skb_load_helper_16_no_cache, const struct sk_buff *, skb,
258 int, offset)
259 {
260 return ____bpf_skb_load_helper_16(skb, skb->data, skb->len - skb->data_len,
261 offset);
262 }
263
BPF_CALL_4(bpf_skb_load_helper_32,const struct sk_buff *,skb,const void *,data,int,headlen,int,offset)264 BPF_CALL_4(bpf_skb_load_helper_32, const struct sk_buff *, skb, const void *,
265 data, int, headlen, int, offset)
266 {
267 u32 tmp, *ptr;
268 const int len = sizeof(tmp);
269
270 if (likely(offset >= 0)) {
271 if (headlen - offset >= len)
272 return get_unaligned_be32(data + offset);
273 if (!skb_copy_bits(skb, offset, &tmp, sizeof(tmp)))
274 return be32_to_cpu(tmp);
275 } else {
276 ptr = bpf_internal_load_pointer_neg_helper(skb, offset, len);
277 if (likely(ptr))
278 return get_unaligned_be32(ptr);
279 }
280
281 return -EFAULT;
282 }
283
BPF_CALL_2(bpf_skb_load_helper_32_no_cache,const struct sk_buff *,skb,int,offset)284 BPF_CALL_2(bpf_skb_load_helper_32_no_cache, const struct sk_buff *, skb,
285 int, offset)
286 {
287 return ____bpf_skb_load_helper_32(skb, skb->data, skb->len - skb->data_len,
288 offset);
289 }
290
convert_skb_access(int skb_field,int dst_reg,int src_reg,struct bpf_insn * insn_buf)291 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
292 struct bpf_insn *insn_buf)
293 {
294 struct bpf_insn *insn = insn_buf;
295
296 switch (skb_field) {
297 case SKF_AD_MARK:
298 BUILD_BUG_ON(sizeof_field(struct sk_buff, mark) != 4);
299
300 *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
301 offsetof(struct sk_buff, mark));
302 break;
303
304 case SKF_AD_PKTTYPE:
305 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET);
306 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
307 #ifdef __BIG_ENDIAN_BITFIELD
308 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
309 #endif
310 break;
311
312 case SKF_AD_QUEUE:
313 BUILD_BUG_ON(sizeof_field(struct sk_buff, queue_mapping) != 2);
314
315 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
316 offsetof(struct sk_buff, queue_mapping));
317 break;
318
319 case SKF_AD_VLAN_TAG:
320 BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_tci) != 2);
321
322 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
323 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
324 offsetof(struct sk_buff, vlan_tci));
325 break;
326 case SKF_AD_VLAN_TAG_PRESENT:
327 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_VLAN_PRESENT_OFFSET);
328 if (PKT_VLAN_PRESENT_BIT)
329 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, PKT_VLAN_PRESENT_BIT);
330 if (PKT_VLAN_PRESENT_BIT < 7)
331 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
332 break;
333 }
334
335 return insn - insn_buf;
336 }
337
convert_bpf_extensions(struct sock_filter * fp,struct bpf_insn ** insnp)338 static bool convert_bpf_extensions(struct sock_filter *fp,
339 struct bpf_insn **insnp)
340 {
341 struct bpf_insn *insn = *insnp;
342 u32 cnt;
343
344 switch (fp->k) {
345 case SKF_AD_OFF + SKF_AD_PROTOCOL:
346 BUILD_BUG_ON(sizeof_field(struct sk_buff, protocol) != 2);
347
348 /* A = *(u16 *) (CTX + offsetof(protocol)) */
349 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
350 offsetof(struct sk_buff, protocol));
351 /* A = ntohs(A) [emitting a nop or swap16] */
352 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
353 break;
354
355 case SKF_AD_OFF + SKF_AD_PKTTYPE:
356 cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
357 insn += cnt - 1;
358 break;
359
360 case SKF_AD_OFF + SKF_AD_IFINDEX:
361 case SKF_AD_OFF + SKF_AD_HATYPE:
362 BUILD_BUG_ON(sizeof_field(struct net_device, ifindex) != 4);
363 BUILD_BUG_ON(sizeof_field(struct net_device, type) != 2);
364
365 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
366 BPF_REG_TMP, BPF_REG_CTX,
367 offsetof(struct sk_buff, dev));
368 /* if (tmp != 0) goto pc + 1 */
369 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
370 *insn++ = BPF_EXIT_INSN();
371 if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
372 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
373 offsetof(struct net_device, ifindex));
374 else
375 *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
376 offsetof(struct net_device, type));
377 break;
378
379 case SKF_AD_OFF + SKF_AD_MARK:
380 cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
381 insn += cnt - 1;
382 break;
383
384 case SKF_AD_OFF + SKF_AD_RXHASH:
385 BUILD_BUG_ON(sizeof_field(struct sk_buff, hash) != 4);
386
387 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
388 offsetof(struct sk_buff, hash));
389 break;
390
391 case SKF_AD_OFF + SKF_AD_QUEUE:
392 cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
393 insn += cnt - 1;
394 break;
395
396 case SKF_AD_OFF + SKF_AD_VLAN_TAG:
397 cnt = convert_skb_access(SKF_AD_VLAN_TAG,
398 BPF_REG_A, BPF_REG_CTX, insn);
399 insn += cnt - 1;
400 break;
401
402 case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
403 cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
404 BPF_REG_A, BPF_REG_CTX, insn);
405 insn += cnt - 1;
406 break;
407
408 case SKF_AD_OFF + SKF_AD_VLAN_TPID:
409 BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_proto) != 2);
410
411 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
412 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
413 offsetof(struct sk_buff, vlan_proto));
414 /* A = ntohs(A) [emitting a nop or swap16] */
415 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
416 break;
417
418 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
419 case SKF_AD_OFF + SKF_AD_NLATTR:
420 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
421 case SKF_AD_OFF + SKF_AD_CPU:
422 case SKF_AD_OFF + SKF_AD_RANDOM:
423 /* arg1 = CTX */
424 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
425 /* arg2 = A */
426 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
427 /* arg3 = X */
428 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
429 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
430 switch (fp->k) {
431 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
432 *insn = BPF_EMIT_CALL(bpf_skb_get_pay_offset);
433 break;
434 case SKF_AD_OFF + SKF_AD_NLATTR:
435 *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr);
436 break;
437 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
438 *insn = BPF_EMIT_CALL(bpf_skb_get_nlattr_nest);
439 break;
440 case SKF_AD_OFF + SKF_AD_CPU:
441 *insn = BPF_EMIT_CALL(bpf_get_raw_cpu_id);
442 break;
443 case SKF_AD_OFF + SKF_AD_RANDOM:
444 *insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
445 bpf_user_rnd_init_once();
446 break;
447 }
448 break;
449
450 case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
451 /* A ^= X */
452 *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
453 break;
454
455 default:
456 /* This is just a dummy call to avoid letting the compiler
457 * evict __bpf_call_base() as an optimization. Placed here
458 * where no-one bothers.
459 */
460 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
461 return false;
462 }
463
464 *insnp = insn;
465 return true;
466 }
467
convert_bpf_ld_abs(struct sock_filter * fp,struct bpf_insn ** insnp)468 static bool convert_bpf_ld_abs(struct sock_filter *fp, struct bpf_insn **insnp)
469 {
470 const bool unaligned_ok = IS_BUILTIN(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS);
471 int size = bpf_size_to_bytes(BPF_SIZE(fp->code));
472 bool endian = BPF_SIZE(fp->code) == BPF_H ||
473 BPF_SIZE(fp->code) == BPF_W;
474 bool indirect = BPF_MODE(fp->code) == BPF_IND;
475 const int ip_align = NET_IP_ALIGN;
476 struct bpf_insn *insn = *insnp;
477 int offset = fp->k;
478
479 if (!indirect &&
480 ((unaligned_ok && offset >= 0) ||
481 (!unaligned_ok && offset >= 0 &&
482 offset + ip_align >= 0 &&
483 offset + ip_align % size == 0))) {
484 bool ldx_off_ok = offset <= S16_MAX;
485
486 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_H);
487 if (offset)
488 *insn++ = BPF_ALU64_IMM(BPF_SUB, BPF_REG_TMP, offset);
489 *insn++ = BPF_JMP_IMM(BPF_JSLT, BPF_REG_TMP,
490 size, 2 + endian + (!ldx_off_ok * 2));
491 if (ldx_off_ok) {
492 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
493 BPF_REG_D, offset);
494 } else {
495 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_D);
496 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_TMP, offset);
497 *insn++ = BPF_LDX_MEM(BPF_SIZE(fp->code), BPF_REG_A,
498 BPF_REG_TMP, 0);
499 }
500 if (endian)
501 *insn++ = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, size * 8);
502 *insn++ = BPF_JMP_A(8);
503 }
504
505 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
506 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_D);
507 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_H);
508 if (!indirect) {
509 *insn++ = BPF_MOV64_IMM(BPF_REG_ARG4, offset);
510 } else {
511 *insn++ = BPF_MOV64_REG(BPF_REG_ARG4, BPF_REG_X);
512 if (fp->k)
513 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_ARG4, offset);
514 }
515
516 switch (BPF_SIZE(fp->code)) {
517 case BPF_B:
518 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8);
519 break;
520 case BPF_H:
521 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16);
522 break;
523 case BPF_W:
524 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32);
525 break;
526 default:
527 return false;
528 }
529
530 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_A, 0, 2);
531 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
532 *insn = BPF_EXIT_INSN();
533
534 *insnp = insn;
535 return true;
536 }
537
538 /**
539 * bpf_convert_filter - convert filter program
540 * @prog: the user passed filter program
541 * @len: the length of the user passed filter program
542 * @new_prog: allocated 'struct bpf_prog' or NULL
543 * @new_len: pointer to store length of converted program
544 * @seen_ld_abs: bool whether we've seen ld_abs/ind
545 *
546 * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
547 * style extended BPF (eBPF).
548 * Conversion workflow:
549 *
550 * 1) First pass for calculating the new program length:
551 * bpf_convert_filter(old_prog, old_len, NULL, &new_len, &seen_ld_abs)
552 *
553 * 2) 2nd pass to remap in two passes: 1st pass finds new
554 * jump offsets, 2nd pass remapping:
555 * bpf_convert_filter(old_prog, old_len, new_prog, &new_len, &seen_ld_abs)
556 */
bpf_convert_filter(struct sock_filter * prog,int len,struct bpf_prog * new_prog,int * new_len,bool * seen_ld_abs)557 static int bpf_convert_filter(struct sock_filter *prog, int len,
558 struct bpf_prog *new_prog, int *new_len,
559 bool *seen_ld_abs)
560 {
561 int new_flen = 0, pass = 0, target, i, stack_off;
562 struct bpf_insn *new_insn, *first_insn = NULL;
563 struct sock_filter *fp;
564 int *addrs = NULL;
565 u8 bpf_src;
566
567 BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
568 BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
569
570 if (len <= 0 || len > BPF_MAXINSNS)
571 return -EINVAL;
572
573 if (new_prog) {
574 first_insn = new_prog->insnsi;
575 addrs = kcalloc(len, sizeof(*addrs),
576 GFP_KERNEL | __GFP_NOWARN);
577 if (!addrs)
578 return -ENOMEM;
579 }
580
581 do_pass:
582 new_insn = first_insn;
583 fp = prog;
584
585 /* Classic BPF related prologue emission. */
586 if (new_prog) {
587 /* Classic BPF expects A and X to be reset first. These need
588 * to be guaranteed to be the first two instructions.
589 */
590 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
591 *new_insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
592
593 /* All programs must keep CTX in callee saved BPF_REG_CTX.
594 * In eBPF case it's done by the compiler, here we need to
595 * do this ourself. Initial CTX is present in BPF_REG_ARG1.
596 */
597 *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
598 if (*seen_ld_abs) {
599 /* For packet access in classic BPF, cache skb->data
600 * in callee-saved BPF R8 and skb->len - skb->data_len
601 * (headlen) in BPF R9. Since classic BPF is read-only
602 * on CTX, we only need to cache it once.
603 */
604 *new_insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
605 BPF_REG_D, BPF_REG_CTX,
606 offsetof(struct sk_buff, data));
607 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_H, BPF_REG_CTX,
608 offsetof(struct sk_buff, len));
609 *new_insn++ = BPF_LDX_MEM(BPF_W, BPF_REG_TMP, BPF_REG_CTX,
610 offsetof(struct sk_buff, data_len));
611 *new_insn++ = BPF_ALU32_REG(BPF_SUB, BPF_REG_H, BPF_REG_TMP);
612 }
613 } else {
614 new_insn += 3;
615 }
616
617 for (i = 0; i < len; fp++, i++) {
618 struct bpf_insn tmp_insns[32] = { };
619 struct bpf_insn *insn = tmp_insns;
620
621 if (addrs)
622 addrs[i] = new_insn - first_insn;
623
624 switch (fp->code) {
625 /* All arithmetic insns and skb loads map as-is. */
626 case BPF_ALU | BPF_ADD | BPF_X:
627 case BPF_ALU | BPF_ADD | BPF_K:
628 case BPF_ALU | BPF_SUB | BPF_X:
629 case BPF_ALU | BPF_SUB | BPF_K:
630 case BPF_ALU | BPF_AND | BPF_X:
631 case BPF_ALU | BPF_AND | BPF_K:
632 case BPF_ALU | BPF_OR | BPF_X:
633 case BPF_ALU | BPF_OR | BPF_K:
634 case BPF_ALU | BPF_LSH | BPF_X:
635 case BPF_ALU | BPF_LSH | BPF_K:
636 case BPF_ALU | BPF_RSH | BPF_X:
637 case BPF_ALU | BPF_RSH | BPF_K:
638 case BPF_ALU | BPF_XOR | BPF_X:
639 case BPF_ALU | BPF_XOR | BPF_K:
640 case BPF_ALU | BPF_MUL | BPF_X:
641 case BPF_ALU | BPF_MUL | BPF_K:
642 case BPF_ALU | BPF_DIV | BPF_X:
643 case BPF_ALU | BPF_DIV | BPF_K:
644 case BPF_ALU | BPF_MOD | BPF_X:
645 case BPF_ALU | BPF_MOD | BPF_K:
646 case BPF_ALU | BPF_NEG:
647 case BPF_LD | BPF_ABS | BPF_W:
648 case BPF_LD | BPF_ABS | BPF_H:
649 case BPF_LD | BPF_ABS | BPF_B:
650 case BPF_LD | BPF_IND | BPF_W:
651 case BPF_LD | BPF_IND | BPF_H:
652 case BPF_LD | BPF_IND | BPF_B:
653 /* Check for overloaded BPF extension and
654 * directly convert it if found, otherwise
655 * just move on with mapping.
656 */
657 if (BPF_CLASS(fp->code) == BPF_LD &&
658 BPF_MODE(fp->code) == BPF_ABS &&
659 convert_bpf_extensions(fp, &insn))
660 break;
661 if (BPF_CLASS(fp->code) == BPF_LD &&
662 convert_bpf_ld_abs(fp, &insn)) {
663 *seen_ld_abs = true;
664 break;
665 }
666
667 if (fp->code == (BPF_ALU | BPF_DIV | BPF_X) ||
668 fp->code == (BPF_ALU | BPF_MOD | BPF_X)) {
669 *insn++ = BPF_MOV32_REG(BPF_REG_X, BPF_REG_X);
670 /* Error with exception code on div/mod by 0.
671 * For cBPF programs, this was always return 0.
672 */
673 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_X, 0, 2);
674 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
675 *insn++ = BPF_EXIT_INSN();
676 }
677
678 *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
679 break;
680
681 /* Jump transformation cannot use BPF block macros
682 * everywhere as offset calculation and target updates
683 * require a bit more work than the rest, i.e. jump
684 * opcodes map as-is, but offsets need adjustment.
685 */
686
687 #define BPF_EMIT_JMP \
688 do { \
689 const s32 off_min = S16_MIN, off_max = S16_MAX; \
690 s32 off; \
691 \
692 if (target >= len || target < 0) \
693 goto err; \
694 off = addrs ? addrs[target] - addrs[i] - 1 : 0; \
695 /* Adjust pc relative offset for 2nd or 3rd insn. */ \
696 off -= insn - tmp_insns; \
697 /* Reject anything not fitting into insn->off. */ \
698 if (off < off_min || off > off_max) \
699 goto err; \
700 insn->off = off; \
701 } while (0)
702
703 case BPF_JMP | BPF_JA:
704 target = i + fp->k + 1;
705 insn->code = fp->code;
706 BPF_EMIT_JMP;
707 break;
708
709 case BPF_JMP | BPF_JEQ | BPF_K:
710 case BPF_JMP | BPF_JEQ | BPF_X:
711 case BPF_JMP | BPF_JSET | BPF_K:
712 case BPF_JMP | BPF_JSET | BPF_X:
713 case BPF_JMP | BPF_JGT | BPF_K:
714 case BPF_JMP | BPF_JGT | BPF_X:
715 case BPF_JMP | BPF_JGE | BPF_K:
716 case BPF_JMP | BPF_JGE | BPF_X:
717 if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
718 /* BPF immediates are signed, zero extend
719 * immediate into tmp register and use it
720 * in compare insn.
721 */
722 *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
723
724 insn->dst_reg = BPF_REG_A;
725 insn->src_reg = BPF_REG_TMP;
726 bpf_src = BPF_X;
727 } else {
728 insn->dst_reg = BPF_REG_A;
729 insn->imm = fp->k;
730 bpf_src = BPF_SRC(fp->code);
731 insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
732 }
733
734 /* Common case where 'jump_false' is next insn. */
735 if (fp->jf == 0) {
736 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
737 target = i + fp->jt + 1;
738 BPF_EMIT_JMP;
739 break;
740 }
741
742 /* Convert some jumps when 'jump_true' is next insn. */
743 if (fp->jt == 0) {
744 switch (BPF_OP(fp->code)) {
745 case BPF_JEQ:
746 insn->code = BPF_JMP | BPF_JNE | bpf_src;
747 break;
748 case BPF_JGT:
749 insn->code = BPF_JMP | BPF_JLE | bpf_src;
750 break;
751 case BPF_JGE:
752 insn->code = BPF_JMP | BPF_JLT | bpf_src;
753 break;
754 default:
755 goto jmp_rest;
756 }
757
758 target = i + fp->jf + 1;
759 BPF_EMIT_JMP;
760 break;
761 }
762 jmp_rest:
763 /* Other jumps are mapped into two insns: Jxx and JA. */
764 target = i + fp->jt + 1;
765 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
766 BPF_EMIT_JMP;
767 insn++;
768
769 insn->code = BPF_JMP | BPF_JA;
770 target = i + fp->jf + 1;
771 BPF_EMIT_JMP;
772 break;
773
774 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
775 case BPF_LDX | BPF_MSH | BPF_B: {
776 struct sock_filter tmp = {
777 .code = BPF_LD | BPF_ABS | BPF_B,
778 .k = fp->k,
779 };
780
781 *seen_ld_abs = true;
782
783 /* X = A */
784 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
785 /* A = BPF_R0 = *(u8 *) (skb->data + K) */
786 convert_bpf_ld_abs(&tmp, &insn);
787 insn++;
788 /* A &= 0xf */
789 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
790 /* A <<= 2 */
791 *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
792 /* tmp = X */
793 *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_X);
794 /* X = A */
795 *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
796 /* A = tmp */
797 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
798 break;
799 }
800 /* RET_K is remaped into 2 insns. RET_A case doesn't need an
801 * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
802 */
803 case BPF_RET | BPF_A:
804 case BPF_RET | BPF_K:
805 if (BPF_RVAL(fp->code) == BPF_K)
806 *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
807 0, fp->k);
808 *insn = BPF_EXIT_INSN();
809 break;
810
811 /* Store to stack. */
812 case BPF_ST:
813 case BPF_STX:
814 stack_off = fp->k * 4 + 4;
815 *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
816 BPF_ST ? BPF_REG_A : BPF_REG_X,
817 -stack_off);
818 /* check_load_and_stores() verifies that classic BPF can
819 * load from stack only after write, so tracking
820 * stack_depth for ST|STX insns is enough
821 */
822 if (new_prog && new_prog->aux->stack_depth < stack_off)
823 new_prog->aux->stack_depth = stack_off;
824 break;
825
826 /* Load from stack. */
827 case BPF_LD | BPF_MEM:
828 case BPF_LDX | BPF_MEM:
829 stack_off = fp->k * 4 + 4;
830 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
831 BPF_REG_A : BPF_REG_X, BPF_REG_FP,
832 -stack_off);
833 break;
834
835 /* A = K or X = K */
836 case BPF_LD | BPF_IMM:
837 case BPF_LDX | BPF_IMM:
838 *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
839 BPF_REG_A : BPF_REG_X, fp->k);
840 break;
841
842 /* X = A */
843 case BPF_MISC | BPF_TAX:
844 *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
845 break;
846
847 /* A = X */
848 case BPF_MISC | BPF_TXA:
849 *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
850 break;
851
852 /* A = skb->len or X = skb->len */
853 case BPF_LD | BPF_W | BPF_LEN:
854 case BPF_LDX | BPF_W | BPF_LEN:
855 *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
856 BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
857 offsetof(struct sk_buff, len));
858 break;
859
860 /* Access seccomp_data fields. */
861 case BPF_LDX | BPF_ABS | BPF_W:
862 /* A = *(u32 *) (ctx + K) */
863 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
864 break;
865
866 /* Unknown instruction. */
867 default:
868 goto err;
869 }
870
871 insn++;
872 if (new_prog)
873 memcpy(new_insn, tmp_insns,
874 sizeof(*insn) * (insn - tmp_insns));
875 new_insn += insn - tmp_insns;
876 }
877
878 if (!new_prog) {
879 /* Only calculating new length. */
880 *new_len = new_insn - first_insn;
881 if (*seen_ld_abs)
882 *new_len += 4; /* Prologue bits. */
883 return 0;
884 }
885
886 pass++;
887 if (new_flen != new_insn - first_insn) {
888 new_flen = new_insn - first_insn;
889 if (pass > 2)
890 goto err;
891 goto do_pass;
892 }
893
894 kfree(addrs);
895 BUG_ON(*new_len != new_flen);
896 return 0;
897 err:
898 kfree(addrs);
899 return -EINVAL;
900 }
901
902 /* Security:
903 *
904 * As we dont want to clear mem[] array for each packet going through
905 * __bpf_prog_run(), we check that filter loaded by user never try to read
906 * a cell if not previously written, and we check all branches to be sure
907 * a malicious user doesn't try to abuse us.
908 */
check_load_and_stores(const struct sock_filter * filter,int flen)909 static int check_load_and_stores(const struct sock_filter *filter, int flen)
910 {
911 u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
912 int pc, ret = 0;
913
914 BUILD_BUG_ON(BPF_MEMWORDS > 16);
915
916 masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
917 if (!masks)
918 return -ENOMEM;
919
920 memset(masks, 0xff, flen * sizeof(*masks));
921
922 for (pc = 0; pc < flen; pc++) {
923 memvalid &= masks[pc];
924
925 switch (filter[pc].code) {
926 case BPF_ST:
927 case BPF_STX:
928 memvalid |= (1 << filter[pc].k);
929 break;
930 case BPF_LD | BPF_MEM:
931 case BPF_LDX | BPF_MEM:
932 if (!(memvalid & (1 << filter[pc].k))) {
933 ret = -EINVAL;
934 goto error;
935 }
936 break;
937 case BPF_JMP | BPF_JA:
938 /* A jump must set masks on target */
939 masks[pc + 1 + filter[pc].k] &= memvalid;
940 memvalid = ~0;
941 break;
942 case BPF_JMP | BPF_JEQ | BPF_K:
943 case BPF_JMP | BPF_JEQ | BPF_X:
944 case BPF_JMP | BPF_JGE | BPF_K:
945 case BPF_JMP | BPF_JGE | BPF_X:
946 case BPF_JMP | BPF_JGT | BPF_K:
947 case BPF_JMP | BPF_JGT | BPF_X:
948 case BPF_JMP | BPF_JSET | BPF_K:
949 case BPF_JMP | BPF_JSET | BPF_X:
950 /* A jump must set masks on targets */
951 masks[pc + 1 + filter[pc].jt] &= memvalid;
952 masks[pc + 1 + filter[pc].jf] &= memvalid;
953 memvalid = ~0;
954 break;
955 }
956 }
957 error:
958 kfree(masks);
959 return ret;
960 }
961
chk_code_allowed(u16 code_to_probe)962 static bool chk_code_allowed(u16 code_to_probe)
963 {
964 static const bool codes[] = {
965 /* 32 bit ALU operations */
966 [BPF_ALU | BPF_ADD | BPF_K] = true,
967 [BPF_ALU | BPF_ADD | BPF_X] = true,
968 [BPF_ALU | BPF_SUB | BPF_K] = true,
969 [BPF_ALU | BPF_SUB | BPF_X] = true,
970 [BPF_ALU | BPF_MUL | BPF_K] = true,
971 [BPF_ALU | BPF_MUL | BPF_X] = true,
972 [BPF_ALU | BPF_DIV | BPF_K] = true,
973 [BPF_ALU | BPF_DIV | BPF_X] = true,
974 [BPF_ALU | BPF_MOD | BPF_K] = true,
975 [BPF_ALU | BPF_MOD | BPF_X] = true,
976 [BPF_ALU | BPF_AND | BPF_K] = true,
977 [BPF_ALU | BPF_AND | BPF_X] = true,
978 [BPF_ALU | BPF_OR | BPF_K] = true,
979 [BPF_ALU | BPF_OR | BPF_X] = true,
980 [BPF_ALU | BPF_XOR | BPF_K] = true,
981 [BPF_ALU | BPF_XOR | BPF_X] = true,
982 [BPF_ALU | BPF_LSH | BPF_K] = true,
983 [BPF_ALU | BPF_LSH | BPF_X] = true,
984 [BPF_ALU | BPF_RSH | BPF_K] = true,
985 [BPF_ALU | BPF_RSH | BPF_X] = true,
986 [BPF_ALU | BPF_NEG] = true,
987 /* Load instructions */
988 [BPF_LD | BPF_W | BPF_ABS] = true,
989 [BPF_LD | BPF_H | BPF_ABS] = true,
990 [BPF_LD | BPF_B | BPF_ABS] = true,
991 [BPF_LD | BPF_W | BPF_LEN] = true,
992 [BPF_LD | BPF_W | BPF_IND] = true,
993 [BPF_LD | BPF_H | BPF_IND] = true,
994 [BPF_LD | BPF_B | BPF_IND] = true,
995 [BPF_LD | BPF_IMM] = true,
996 [BPF_LD | BPF_MEM] = true,
997 [BPF_LDX | BPF_W | BPF_LEN] = true,
998 [BPF_LDX | BPF_B | BPF_MSH] = true,
999 [BPF_LDX | BPF_IMM] = true,
1000 [BPF_LDX | BPF_MEM] = true,
1001 /* Store instructions */
1002 [BPF_ST] = true,
1003 [BPF_STX] = true,
1004 /* Misc instructions */
1005 [BPF_MISC | BPF_TAX] = true,
1006 [BPF_MISC | BPF_TXA] = true,
1007 /* Return instructions */
1008 [BPF_RET | BPF_K] = true,
1009 [BPF_RET | BPF_A] = true,
1010 /* Jump instructions */
1011 [BPF_JMP | BPF_JA] = true,
1012 [BPF_JMP | BPF_JEQ | BPF_K] = true,
1013 [BPF_JMP | BPF_JEQ | BPF_X] = true,
1014 [BPF_JMP | BPF_JGE | BPF_K] = true,
1015 [BPF_JMP | BPF_JGE | BPF_X] = true,
1016 [BPF_JMP | BPF_JGT | BPF_K] = true,
1017 [BPF_JMP | BPF_JGT | BPF_X] = true,
1018 [BPF_JMP | BPF_JSET | BPF_K] = true,
1019 [BPF_JMP | BPF_JSET | BPF_X] = true,
1020 };
1021
1022 if (code_to_probe >= ARRAY_SIZE(codes))
1023 return false;
1024
1025 return codes[code_to_probe];
1026 }
1027
bpf_check_basics_ok(const struct sock_filter * filter,unsigned int flen)1028 static bool bpf_check_basics_ok(const struct sock_filter *filter,
1029 unsigned int flen)
1030 {
1031 if (filter == NULL)
1032 return false;
1033 if (flen == 0 || flen > BPF_MAXINSNS)
1034 return false;
1035
1036 return true;
1037 }
1038
1039 /**
1040 * bpf_check_classic - verify socket filter code
1041 * @filter: filter to verify
1042 * @flen: length of filter
1043 *
1044 * Check the user's filter code. If we let some ugly
1045 * filter code slip through kaboom! The filter must contain
1046 * no references or jumps that are out of range, no illegal
1047 * instructions, and must end with a RET instruction.
1048 *
1049 * All jumps are forward as they are not signed.
1050 *
1051 * Returns 0 if the rule set is legal or -EINVAL if not.
1052 */
bpf_check_classic(const struct sock_filter * filter,unsigned int flen)1053 static int bpf_check_classic(const struct sock_filter *filter,
1054 unsigned int flen)
1055 {
1056 bool anc_found;
1057 int pc;
1058
1059 /* Check the filter code now */
1060 for (pc = 0; pc < flen; pc++) {
1061 const struct sock_filter *ftest = &filter[pc];
1062
1063 /* May we actually operate on this code? */
1064 if (!chk_code_allowed(ftest->code))
1065 return -EINVAL;
1066
1067 /* Some instructions need special checks */
1068 switch (ftest->code) {
1069 case BPF_ALU | BPF_DIV | BPF_K:
1070 case BPF_ALU | BPF_MOD | BPF_K:
1071 /* Check for division by zero */
1072 if (ftest->k == 0)
1073 return -EINVAL;
1074 break;
1075 case BPF_ALU | BPF_LSH | BPF_K:
1076 case BPF_ALU | BPF_RSH | BPF_K:
1077 if (ftest->k >= 32)
1078 return -EINVAL;
1079 break;
1080 case BPF_LD | BPF_MEM:
1081 case BPF_LDX | BPF_MEM:
1082 case BPF_ST:
1083 case BPF_STX:
1084 /* Check for invalid memory addresses */
1085 if (ftest->k >= BPF_MEMWORDS)
1086 return -EINVAL;
1087 break;
1088 case BPF_JMP | BPF_JA:
1089 /* Note, the large ftest->k might cause loops.
1090 * Compare this with conditional jumps below,
1091 * where offsets are limited. --ANK (981016)
1092 */
1093 if (ftest->k >= (unsigned int)(flen - pc - 1))
1094 return -EINVAL;
1095 break;
1096 case BPF_JMP | BPF_JEQ | BPF_K:
1097 case BPF_JMP | BPF_JEQ | BPF_X:
1098 case BPF_JMP | BPF_JGE | BPF_K:
1099 case BPF_JMP | BPF_JGE | BPF_X:
1100 case BPF_JMP | BPF_JGT | BPF_K:
1101 case BPF_JMP | BPF_JGT | BPF_X:
1102 case BPF_JMP | BPF_JSET | BPF_K:
1103 case BPF_JMP | BPF_JSET | BPF_X:
1104 /* Both conditionals must be safe */
1105 if (pc + ftest->jt + 1 >= flen ||
1106 pc + ftest->jf + 1 >= flen)
1107 return -EINVAL;
1108 break;
1109 case BPF_LD | BPF_W | BPF_ABS:
1110 case BPF_LD | BPF_H | BPF_ABS:
1111 case BPF_LD | BPF_B | BPF_ABS:
1112 anc_found = false;
1113 if (bpf_anc_helper(ftest) & BPF_ANC)
1114 anc_found = true;
1115 /* Ancillary operation unknown or unsupported */
1116 if (anc_found == false && ftest->k >= SKF_AD_OFF)
1117 return -EINVAL;
1118 }
1119 }
1120
1121 /* Last instruction must be a RET code */
1122 switch (filter[flen - 1].code) {
1123 case BPF_RET | BPF_K:
1124 case BPF_RET | BPF_A:
1125 return check_load_and_stores(filter, flen);
1126 }
1127
1128 return -EINVAL;
1129 }
1130
bpf_prog_store_orig_filter(struct bpf_prog * fp,const struct sock_fprog * fprog)1131 static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
1132 const struct sock_fprog *fprog)
1133 {
1134 unsigned int fsize = bpf_classic_proglen(fprog);
1135 struct sock_fprog_kern *fkprog;
1136
1137 fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
1138 if (!fp->orig_prog)
1139 return -ENOMEM;
1140
1141 fkprog = fp->orig_prog;
1142 fkprog->len = fprog->len;
1143
1144 fkprog->filter = kmemdup(fp->insns, fsize,
1145 GFP_KERNEL | __GFP_NOWARN);
1146 if (!fkprog->filter) {
1147 kfree(fp->orig_prog);
1148 return -ENOMEM;
1149 }
1150
1151 return 0;
1152 }
1153
bpf_release_orig_filter(struct bpf_prog * fp)1154 static void bpf_release_orig_filter(struct bpf_prog *fp)
1155 {
1156 struct sock_fprog_kern *fprog = fp->orig_prog;
1157
1158 if (fprog) {
1159 kfree(fprog->filter);
1160 kfree(fprog);
1161 }
1162 }
1163
__bpf_prog_release(struct bpf_prog * prog)1164 static void __bpf_prog_release(struct bpf_prog *prog)
1165 {
1166 if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
1167 bpf_prog_put(prog);
1168 } else {
1169 bpf_release_orig_filter(prog);
1170 bpf_prog_free(prog);
1171 }
1172 }
1173
__sk_filter_release(struct sk_filter * fp)1174 static void __sk_filter_release(struct sk_filter *fp)
1175 {
1176 __bpf_prog_release(fp->prog);
1177 kfree(fp);
1178 }
1179
1180 /**
1181 * sk_filter_release_rcu - Release a socket filter by rcu_head
1182 * @rcu: rcu_head that contains the sk_filter to free
1183 */
sk_filter_release_rcu(struct rcu_head * rcu)1184 static void sk_filter_release_rcu(struct rcu_head *rcu)
1185 {
1186 struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
1187
1188 __sk_filter_release(fp);
1189 }
1190
1191 /**
1192 * sk_filter_release - release a socket filter
1193 * @fp: filter to remove
1194 *
1195 * Remove a filter from a socket and release its resources.
1196 */
sk_filter_release(struct sk_filter * fp)1197 static void sk_filter_release(struct sk_filter *fp)
1198 {
1199 if (refcount_dec_and_test(&fp->refcnt))
1200 call_rcu(&fp->rcu, sk_filter_release_rcu);
1201 }
1202
sk_filter_uncharge(struct sock * sk,struct sk_filter * fp)1203 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
1204 {
1205 u32 filter_size = bpf_prog_size(fp->prog->len);
1206
1207 atomic_sub(filter_size, &sk->sk_omem_alloc);
1208 sk_filter_release(fp);
1209 }
1210
1211 /* try to charge the socket memory if there is space available
1212 * return true on success
1213 */
__sk_filter_charge(struct sock * sk,struct sk_filter * fp)1214 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1215 {
1216 u32 filter_size = bpf_prog_size(fp->prog->len);
1217 int optmem_max = READ_ONCE(sysctl_optmem_max);
1218
1219 /* same check as in sock_kmalloc() */
1220 if (filter_size <= optmem_max &&
1221 atomic_read(&sk->sk_omem_alloc) + filter_size < optmem_max) {
1222 atomic_add(filter_size, &sk->sk_omem_alloc);
1223 return true;
1224 }
1225 return false;
1226 }
1227
sk_filter_charge(struct sock * sk,struct sk_filter * fp)1228 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
1229 {
1230 if (!refcount_inc_not_zero(&fp->refcnt))
1231 return false;
1232
1233 if (!__sk_filter_charge(sk, fp)) {
1234 sk_filter_release(fp);
1235 return false;
1236 }
1237 return true;
1238 }
1239
bpf_migrate_filter(struct bpf_prog * fp)1240 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
1241 {
1242 struct sock_filter *old_prog;
1243 struct bpf_prog *old_fp;
1244 int err, new_len, old_len = fp->len;
1245 bool seen_ld_abs = false;
1246
1247 /* We are free to overwrite insns et al right here as it won't be used at
1248 * this point in time anymore internally after the migration to the eBPF
1249 * instruction representation.
1250 */
1251 BUILD_BUG_ON(sizeof(struct sock_filter) !=
1252 sizeof(struct bpf_insn));
1253
1254 /* Conversion cannot happen on overlapping memory areas,
1255 * so we need to keep the user BPF around until the 2nd
1256 * pass. At this time, the user BPF is stored in fp->insns.
1257 */
1258 old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
1259 GFP_KERNEL | __GFP_NOWARN);
1260 if (!old_prog) {
1261 err = -ENOMEM;
1262 goto out_err;
1263 }
1264
1265 /* 1st pass: calculate the new program length. */
1266 err = bpf_convert_filter(old_prog, old_len, NULL, &new_len,
1267 &seen_ld_abs);
1268 if (err)
1269 goto out_err_free;
1270
1271 /* Expand fp for appending the new filter representation. */
1272 old_fp = fp;
1273 fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
1274 if (!fp) {
1275 /* The old_fp is still around in case we couldn't
1276 * allocate new memory, so uncharge on that one.
1277 */
1278 fp = old_fp;
1279 err = -ENOMEM;
1280 goto out_err_free;
1281 }
1282
1283 fp->len = new_len;
1284
1285 /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1286 err = bpf_convert_filter(old_prog, old_len, fp, &new_len,
1287 &seen_ld_abs);
1288 if (err)
1289 /* 2nd bpf_convert_filter() can fail only if it fails
1290 * to allocate memory, remapping must succeed. Note,
1291 * that at this time old_fp has already been released
1292 * by krealloc().
1293 */
1294 goto out_err_free;
1295
1296 fp = bpf_prog_select_runtime(fp, &err);
1297 if (err)
1298 goto out_err_free;
1299
1300 kfree(old_prog);
1301 return fp;
1302
1303 out_err_free:
1304 kfree(old_prog);
1305 out_err:
1306 __bpf_prog_release(fp);
1307 return ERR_PTR(err);
1308 }
1309
bpf_prepare_filter(struct bpf_prog * fp,bpf_aux_classic_check_t trans)1310 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
1311 bpf_aux_classic_check_t trans)
1312 {
1313 int err;
1314
1315 fp->bpf_func = NULL;
1316 fp->jited = 0;
1317
1318 err = bpf_check_classic(fp->insns, fp->len);
1319 if (err) {
1320 __bpf_prog_release(fp);
1321 return ERR_PTR(err);
1322 }
1323
1324 /* There might be additional checks and transformations
1325 * needed on classic filters, f.e. in case of seccomp.
1326 */
1327 if (trans) {
1328 err = trans(fp->insns, fp->len);
1329 if (err) {
1330 __bpf_prog_release(fp);
1331 return ERR_PTR(err);
1332 }
1333 }
1334
1335 /* Probe if we can JIT compile the filter and if so, do
1336 * the compilation of the filter.
1337 */
1338 bpf_jit_compile(fp);
1339
1340 /* JIT compiler couldn't process this filter, so do the eBPF translation
1341 * for the optimized interpreter.
1342 */
1343 if (!fp->jited)
1344 fp = bpf_migrate_filter(fp);
1345
1346 return fp;
1347 }
1348
1349 /**
1350 * bpf_prog_create - create an unattached filter
1351 * @pfp: the unattached filter that is created
1352 * @fprog: the filter program
1353 *
1354 * Create a filter independent of any socket. We first run some
1355 * sanity checks on it to make sure it does not explode on us later.
1356 * If an error occurs or there is insufficient memory for the filter
1357 * a negative errno code is returned. On success the return is zero.
1358 */
bpf_prog_create(struct bpf_prog ** pfp,struct sock_fprog_kern * fprog)1359 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
1360 {
1361 unsigned int fsize = bpf_classic_proglen(fprog);
1362 struct bpf_prog *fp;
1363
1364 /* Make sure new filter is there and in the right amounts. */
1365 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1366 return -EINVAL;
1367
1368 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1369 if (!fp)
1370 return -ENOMEM;
1371
1372 memcpy(fp->insns, fprog->filter, fsize);
1373
1374 fp->len = fprog->len;
1375 /* Since unattached filters are not copied back to user
1376 * space through sk_get_filter(), we do not need to hold
1377 * a copy here, and can spare us the work.
1378 */
1379 fp->orig_prog = NULL;
1380
1381 /* bpf_prepare_filter() already takes care of freeing
1382 * memory in case something goes wrong.
1383 */
1384 fp = bpf_prepare_filter(fp, NULL);
1385 if (IS_ERR(fp))
1386 return PTR_ERR(fp);
1387
1388 *pfp = fp;
1389 return 0;
1390 }
1391 EXPORT_SYMBOL_GPL(bpf_prog_create);
1392
1393 /**
1394 * bpf_prog_create_from_user - create an unattached filter from user buffer
1395 * @pfp: the unattached filter that is created
1396 * @fprog: the filter program
1397 * @trans: post-classic verifier transformation handler
1398 * @save_orig: save classic BPF program
1399 *
1400 * This function effectively does the same as bpf_prog_create(), only
1401 * that it builds up its insns buffer from user space provided buffer.
1402 * It also allows for passing a bpf_aux_classic_check_t handler.
1403 */
bpf_prog_create_from_user(struct bpf_prog ** pfp,struct sock_fprog * fprog,bpf_aux_classic_check_t trans,bool save_orig)1404 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1405 bpf_aux_classic_check_t trans, bool save_orig)
1406 {
1407 unsigned int fsize = bpf_classic_proglen(fprog);
1408 struct bpf_prog *fp;
1409 int err;
1410
1411 /* Make sure new filter is there and in the right amounts. */
1412 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1413 return -EINVAL;
1414
1415 fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1416 if (!fp)
1417 return -ENOMEM;
1418
1419 if (copy_from_user(fp->insns, fprog->filter, fsize)) {
1420 __bpf_prog_free(fp);
1421 return -EFAULT;
1422 }
1423
1424 fp->len = fprog->len;
1425 fp->orig_prog = NULL;
1426
1427 if (save_orig) {
1428 err = bpf_prog_store_orig_filter(fp, fprog);
1429 if (err) {
1430 __bpf_prog_free(fp);
1431 return -ENOMEM;
1432 }
1433 }
1434
1435 /* bpf_prepare_filter() already takes care of freeing
1436 * memory in case something goes wrong.
1437 */
1438 fp = bpf_prepare_filter(fp, trans);
1439 if (IS_ERR(fp))
1440 return PTR_ERR(fp);
1441
1442 *pfp = fp;
1443 return 0;
1444 }
1445 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
1446
bpf_prog_destroy(struct bpf_prog * fp)1447 void bpf_prog_destroy(struct bpf_prog *fp)
1448 {
1449 __bpf_prog_release(fp);
1450 }
1451 EXPORT_SYMBOL_GPL(bpf_prog_destroy);
1452
__sk_attach_prog(struct bpf_prog * prog,struct sock * sk)1453 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
1454 {
1455 struct sk_filter *fp, *old_fp;
1456
1457 fp = kmalloc(sizeof(*fp), GFP_KERNEL);
1458 if (!fp)
1459 return -ENOMEM;
1460
1461 fp->prog = prog;
1462
1463 if (!__sk_filter_charge(sk, fp)) {
1464 kfree(fp);
1465 return -ENOMEM;
1466 }
1467 refcount_set(&fp->refcnt, 1);
1468
1469 old_fp = rcu_dereference_protected(sk->sk_filter,
1470 lockdep_sock_is_held(sk));
1471 rcu_assign_pointer(sk->sk_filter, fp);
1472
1473 if (old_fp)
1474 sk_filter_uncharge(sk, old_fp);
1475
1476 return 0;
1477 }
1478
1479 static
__get_filter(struct sock_fprog * fprog,struct sock * sk)1480 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
1481 {
1482 unsigned int fsize = bpf_classic_proglen(fprog);
1483 struct bpf_prog *prog;
1484 int err;
1485
1486 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1487 return ERR_PTR(-EPERM);
1488
1489 /* Make sure new filter is there and in the right amounts. */
1490 if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1491 return ERR_PTR(-EINVAL);
1492
1493 prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1494 if (!prog)
1495 return ERR_PTR(-ENOMEM);
1496
1497 if (copy_from_user(prog->insns, fprog->filter, fsize)) {
1498 __bpf_prog_free(prog);
1499 return ERR_PTR(-EFAULT);
1500 }
1501
1502 prog->len = fprog->len;
1503
1504 err = bpf_prog_store_orig_filter(prog, fprog);
1505 if (err) {
1506 __bpf_prog_free(prog);
1507 return ERR_PTR(-ENOMEM);
1508 }
1509
1510 /* bpf_prepare_filter() already takes care of freeing
1511 * memory in case something goes wrong.
1512 */
1513 return bpf_prepare_filter(prog, NULL);
1514 }
1515
1516 /**
1517 * sk_attach_filter - attach a socket filter
1518 * @fprog: the filter program
1519 * @sk: the socket to use
1520 *
1521 * Attach the user's filter code. We first run some sanity checks on
1522 * it to make sure it does not explode on us later. If an error
1523 * occurs or there is insufficient memory for the filter a negative
1524 * errno code is returned. On success the return is zero.
1525 */
sk_attach_filter(struct sock_fprog * fprog,struct sock * sk)1526 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1527 {
1528 struct bpf_prog *prog = __get_filter(fprog, sk);
1529 int err;
1530
1531 if (IS_ERR(prog))
1532 return PTR_ERR(prog);
1533
1534 err = __sk_attach_prog(prog, sk);
1535 if (err < 0) {
1536 __bpf_prog_release(prog);
1537 return err;
1538 }
1539
1540 return 0;
1541 }
1542 EXPORT_SYMBOL_GPL(sk_attach_filter);
1543
sk_reuseport_attach_filter(struct sock_fprog * fprog,struct sock * sk)1544 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1545 {
1546 struct bpf_prog *prog = __get_filter(fprog, sk);
1547 int err;
1548
1549 if (IS_ERR(prog))
1550 return PTR_ERR(prog);
1551
1552 if (bpf_prog_size(prog->len) > READ_ONCE(sysctl_optmem_max))
1553 err = -ENOMEM;
1554 else
1555 err = reuseport_attach_prog(sk, prog);
1556
1557 if (err)
1558 __bpf_prog_release(prog);
1559
1560 return err;
1561 }
1562
__get_bpf(u32 ufd,struct sock * sk)1563 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
1564 {
1565 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1566 return ERR_PTR(-EPERM);
1567
1568 return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1569 }
1570
sk_attach_bpf(u32 ufd,struct sock * sk)1571 int sk_attach_bpf(u32 ufd, struct sock *sk)
1572 {
1573 struct bpf_prog *prog = __get_bpf(ufd, sk);
1574 int err;
1575
1576 if (IS_ERR(prog))
1577 return PTR_ERR(prog);
1578
1579 err = __sk_attach_prog(prog, sk);
1580 if (err < 0) {
1581 bpf_prog_put(prog);
1582 return err;
1583 }
1584
1585 return 0;
1586 }
1587
sk_reuseport_attach_bpf(u32 ufd,struct sock * sk)1588 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
1589 {
1590 struct bpf_prog *prog;
1591 int err;
1592
1593 if (sock_flag(sk, SOCK_FILTER_LOCKED))
1594 return -EPERM;
1595
1596 prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1597 if (PTR_ERR(prog) == -EINVAL)
1598 prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SK_REUSEPORT);
1599 if (IS_ERR(prog))
1600 return PTR_ERR(prog);
1601
1602 if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) {
1603 /* Like other non BPF_PROG_TYPE_SOCKET_FILTER
1604 * bpf prog (e.g. sockmap). It depends on the
1605 * limitation imposed by bpf_prog_load().
1606 * Hence, sysctl_optmem_max is not checked.
1607 */
1608 if ((sk->sk_type != SOCK_STREAM &&
1609 sk->sk_type != SOCK_DGRAM) ||
1610 (sk->sk_protocol != IPPROTO_UDP &&
1611 sk->sk_protocol != IPPROTO_TCP) ||
1612 (sk->sk_family != AF_INET &&
1613 sk->sk_family != AF_INET6)) {
1614 err = -ENOTSUPP;
1615 goto err_prog_put;
1616 }
1617 } else {
1618 /* BPF_PROG_TYPE_SOCKET_FILTER */
1619 if (bpf_prog_size(prog->len) > READ_ONCE(sysctl_optmem_max)) {
1620 err = -ENOMEM;
1621 goto err_prog_put;
1622 }
1623 }
1624
1625 err = reuseport_attach_prog(sk, prog);
1626 err_prog_put:
1627 if (err)
1628 bpf_prog_put(prog);
1629
1630 return err;
1631 }
1632
sk_reuseport_prog_free(struct bpf_prog * prog)1633 void sk_reuseport_prog_free(struct bpf_prog *prog)
1634 {
1635 if (!prog)
1636 return;
1637
1638 if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT)
1639 bpf_prog_put(prog);
1640 else
1641 bpf_prog_destroy(prog);
1642 }
1643
1644 struct bpf_scratchpad {
1645 union {
1646 __be32 diff[MAX_BPF_STACK / sizeof(__be32)];
1647 u8 buff[MAX_BPF_STACK];
1648 };
1649 };
1650
1651 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
1652
__bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1653 static inline int __bpf_try_make_writable(struct sk_buff *skb,
1654 unsigned int write_len)
1655 {
1656 return skb_ensure_writable(skb, write_len);
1657 }
1658
bpf_try_make_writable(struct sk_buff * skb,unsigned int write_len)1659 static inline int bpf_try_make_writable(struct sk_buff *skb,
1660 unsigned int write_len)
1661 {
1662 int err = __bpf_try_make_writable(skb, write_len);
1663
1664 bpf_compute_data_pointers(skb);
1665 return err;
1666 }
1667
bpf_try_make_head_writable(struct sk_buff * skb)1668 static int bpf_try_make_head_writable(struct sk_buff *skb)
1669 {
1670 return bpf_try_make_writable(skb, skb_headlen(skb));
1671 }
1672
bpf_push_mac_rcsum(struct sk_buff * skb)1673 static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
1674 {
1675 if (skb_at_tc_ingress(skb))
1676 skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1677 }
1678
bpf_pull_mac_rcsum(struct sk_buff * skb)1679 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
1680 {
1681 if (skb_at_tc_ingress(skb))
1682 skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1683 }
1684
BPF_CALL_5(bpf_skb_store_bytes,struct sk_buff *,skb,u32,offset,const void *,from,u32,len,u64,flags)1685 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
1686 const void *, from, u32, len, u64, flags)
1687 {
1688 void *ptr;
1689
1690 if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
1691 return -EINVAL;
1692 if (unlikely(offset > INT_MAX))
1693 return -EFAULT;
1694 if (unlikely(bpf_try_make_writable(skb, offset + len)))
1695 return -EFAULT;
1696
1697 ptr = skb->data + offset;
1698 if (flags & BPF_F_RECOMPUTE_CSUM)
1699 __skb_postpull_rcsum(skb, ptr, len, offset);
1700
1701 memcpy(ptr, from, len);
1702
1703 if (flags & BPF_F_RECOMPUTE_CSUM)
1704 __skb_postpush_rcsum(skb, ptr, len, offset);
1705 if (flags & BPF_F_INVALIDATE_HASH)
1706 skb_clear_hash(skb);
1707
1708 return 0;
1709 }
1710
1711 static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
1712 .func = bpf_skb_store_bytes,
1713 .gpl_only = false,
1714 .ret_type = RET_INTEGER,
1715 .arg1_type = ARG_PTR_TO_CTX,
1716 .arg2_type = ARG_ANYTHING,
1717 .arg3_type = ARG_PTR_TO_MEM | MEM_RDONLY,
1718 .arg4_type = ARG_CONST_SIZE,
1719 .arg5_type = ARG_ANYTHING,
1720 };
1721
BPF_CALL_4(bpf_skb_load_bytes,const struct sk_buff *,skb,u32,offset,void *,to,u32,len)1722 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
1723 void *, to, u32, len)
1724 {
1725 void *ptr;
1726
1727 if (unlikely(offset > INT_MAX))
1728 goto err_clear;
1729
1730 ptr = skb_header_pointer(skb, offset, len, to);
1731 if (unlikely(!ptr))
1732 goto err_clear;
1733 if (ptr != to)
1734 memcpy(to, ptr, len);
1735
1736 return 0;
1737 err_clear:
1738 memset(to, 0, len);
1739 return -EFAULT;
1740 }
1741
1742 static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
1743 .func = bpf_skb_load_bytes,
1744 .gpl_only = false,
1745 .ret_type = RET_INTEGER,
1746 .arg1_type = ARG_PTR_TO_CTX,
1747 .arg2_type = ARG_ANYTHING,
1748 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1749 .arg4_type = ARG_CONST_SIZE,
1750 };
1751
BPF_CALL_4(bpf_flow_dissector_load_bytes,const struct bpf_flow_dissector *,ctx,u32,offset,void *,to,u32,len)1752 BPF_CALL_4(bpf_flow_dissector_load_bytes,
1753 const struct bpf_flow_dissector *, ctx, u32, offset,
1754 void *, to, u32, len)
1755 {
1756 void *ptr;
1757
1758 if (unlikely(offset > 0xffff))
1759 goto err_clear;
1760
1761 if (unlikely(!ctx->skb))
1762 goto err_clear;
1763
1764 ptr = skb_header_pointer(ctx->skb, offset, len, to);
1765 if (unlikely(!ptr))
1766 goto err_clear;
1767 if (ptr != to)
1768 memcpy(to, ptr, len);
1769
1770 return 0;
1771 err_clear:
1772 memset(to, 0, len);
1773 return -EFAULT;
1774 }
1775
1776 static const struct bpf_func_proto bpf_flow_dissector_load_bytes_proto = {
1777 .func = bpf_flow_dissector_load_bytes,
1778 .gpl_only = false,
1779 .ret_type = RET_INTEGER,
1780 .arg1_type = ARG_PTR_TO_CTX,
1781 .arg2_type = ARG_ANYTHING,
1782 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1783 .arg4_type = ARG_CONST_SIZE,
1784 };
1785
BPF_CALL_5(bpf_skb_load_bytes_relative,const struct sk_buff *,skb,u32,offset,void *,to,u32,len,u32,start_header)1786 BPF_CALL_5(bpf_skb_load_bytes_relative, const struct sk_buff *, skb,
1787 u32, offset, void *, to, u32, len, u32, start_header)
1788 {
1789 u8 *end = skb_tail_pointer(skb);
1790 u8 *start, *ptr;
1791
1792 if (unlikely(offset > 0xffff))
1793 goto err_clear;
1794
1795 switch (start_header) {
1796 case BPF_HDR_START_MAC:
1797 if (unlikely(!skb_mac_header_was_set(skb)))
1798 goto err_clear;
1799 start = skb_mac_header(skb);
1800 break;
1801 case BPF_HDR_START_NET:
1802 start = skb_network_header(skb);
1803 break;
1804 default:
1805 goto err_clear;
1806 }
1807
1808 ptr = start + offset;
1809
1810 if (likely(ptr + len <= end)) {
1811 memcpy(to, ptr, len);
1812 return 0;
1813 }
1814
1815 err_clear:
1816 memset(to, 0, len);
1817 return -EFAULT;
1818 }
1819
1820 static const struct bpf_func_proto bpf_skb_load_bytes_relative_proto = {
1821 .func = bpf_skb_load_bytes_relative,
1822 .gpl_only = false,
1823 .ret_type = RET_INTEGER,
1824 .arg1_type = ARG_PTR_TO_CTX,
1825 .arg2_type = ARG_ANYTHING,
1826 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
1827 .arg4_type = ARG_CONST_SIZE,
1828 .arg5_type = ARG_ANYTHING,
1829 };
1830
BPF_CALL_2(bpf_skb_pull_data,struct sk_buff *,skb,u32,len)1831 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
1832 {
1833 /* Idea is the following: should the needed direct read/write
1834 * test fail during runtime, we can pull in more data and redo
1835 * again, since implicitly, we invalidate previous checks here.
1836 *
1837 * Or, since we know how much we need to make read/writeable,
1838 * this can be done once at the program beginning for direct
1839 * access case. By this we overcome limitations of only current
1840 * headroom being accessible.
1841 */
1842 return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
1843 }
1844
1845 static const struct bpf_func_proto bpf_skb_pull_data_proto = {
1846 .func = bpf_skb_pull_data,
1847 .gpl_only = false,
1848 .ret_type = RET_INTEGER,
1849 .arg1_type = ARG_PTR_TO_CTX,
1850 .arg2_type = ARG_ANYTHING,
1851 };
1852
BPF_CALL_1(bpf_sk_fullsock,struct sock *,sk)1853 BPF_CALL_1(bpf_sk_fullsock, struct sock *, sk)
1854 {
1855 return sk_fullsock(sk) ? (unsigned long)sk : (unsigned long)NULL;
1856 }
1857
1858 static const struct bpf_func_proto bpf_sk_fullsock_proto = {
1859 .func = bpf_sk_fullsock,
1860 .gpl_only = false,
1861 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
1862 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
1863 };
1864
sk_skb_try_make_writable(struct sk_buff * skb,unsigned int write_len)1865 static inline int sk_skb_try_make_writable(struct sk_buff *skb,
1866 unsigned int write_len)
1867 {
1868 return __bpf_try_make_writable(skb, write_len);
1869 }
1870
BPF_CALL_2(sk_skb_pull_data,struct sk_buff *,skb,u32,len)1871 BPF_CALL_2(sk_skb_pull_data, struct sk_buff *, skb, u32, len)
1872 {
1873 /* Idea is the following: should the needed direct read/write
1874 * test fail during runtime, we can pull in more data and redo
1875 * again, since implicitly, we invalidate previous checks here.
1876 *
1877 * Or, since we know how much we need to make read/writeable,
1878 * this can be done once at the program beginning for direct
1879 * access case. By this we overcome limitations of only current
1880 * headroom being accessible.
1881 */
1882 return sk_skb_try_make_writable(skb, len ? : skb_headlen(skb));
1883 }
1884
1885 static const struct bpf_func_proto sk_skb_pull_data_proto = {
1886 .func = sk_skb_pull_data,
1887 .gpl_only = false,
1888 .ret_type = RET_INTEGER,
1889 .arg1_type = ARG_PTR_TO_CTX,
1890 .arg2_type = ARG_ANYTHING,
1891 };
1892
BPF_CALL_5(bpf_l3_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1893 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
1894 u64, from, u64, to, u64, flags)
1895 {
1896 __sum16 *ptr;
1897
1898 if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
1899 return -EINVAL;
1900 if (unlikely(offset > 0xffff || offset & 1))
1901 return -EFAULT;
1902 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1903 return -EFAULT;
1904
1905 ptr = (__sum16 *)(skb->data + offset);
1906 switch (flags & BPF_F_HDR_FIELD_MASK) {
1907 case 0:
1908 if (unlikely(from != 0))
1909 return -EINVAL;
1910
1911 csum_replace_by_diff(ptr, to);
1912 break;
1913 case 2:
1914 csum_replace2(ptr, from, to);
1915 break;
1916 case 4:
1917 csum_replace4(ptr, from, to);
1918 break;
1919 default:
1920 return -EINVAL;
1921 }
1922
1923 return 0;
1924 }
1925
1926 static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
1927 .func = bpf_l3_csum_replace,
1928 .gpl_only = false,
1929 .ret_type = RET_INTEGER,
1930 .arg1_type = ARG_PTR_TO_CTX,
1931 .arg2_type = ARG_ANYTHING,
1932 .arg3_type = ARG_ANYTHING,
1933 .arg4_type = ARG_ANYTHING,
1934 .arg5_type = ARG_ANYTHING,
1935 };
1936
BPF_CALL_5(bpf_l4_csum_replace,struct sk_buff *,skb,u32,offset,u64,from,u64,to,u64,flags)1937 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
1938 u64, from, u64, to, u64, flags)
1939 {
1940 bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
1941 bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
1942 bool do_mforce = flags & BPF_F_MARK_ENFORCE;
1943 __sum16 *ptr;
1944
1945 if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
1946 BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
1947 return -EINVAL;
1948 if (unlikely(offset > 0xffff || offset & 1))
1949 return -EFAULT;
1950 if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1951 return -EFAULT;
1952
1953 ptr = (__sum16 *)(skb->data + offset);
1954 if (is_mmzero && !do_mforce && !*ptr)
1955 return 0;
1956
1957 switch (flags & BPF_F_HDR_FIELD_MASK) {
1958 case 0:
1959 if (unlikely(from != 0))
1960 return -EINVAL;
1961
1962 inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
1963 break;
1964 case 2:
1965 inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
1966 break;
1967 case 4:
1968 inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
1969 break;
1970 default:
1971 return -EINVAL;
1972 }
1973
1974 if (is_mmzero && !*ptr)
1975 *ptr = CSUM_MANGLED_0;
1976 return 0;
1977 }
1978
1979 static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
1980 .func = bpf_l4_csum_replace,
1981 .gpl_only = false,
1982 .ret_type = RET_INTEGER,
1983 .arg1_type = ARG_PTR_TO_CTX,
1984 .arg2_type = ARG_ANYTHING,
1985 .arg3_type = ARG_ANYTHING,
1986 .arg4_type = ARG_ANYTHING,
1987 .arg5_type = ARG_ANYTHING,
1988 };
1989
BPF_CALL_5(bpf_csum_diff,__be32 *,from,u32,from_size,__be32 *,to,u32,to_size,__wsum,seed)1990 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
1991 __be32 *, to, u32, to_size, __wsum, seed)
1992 {
1993 struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
1994 u32 diff_size = from_size + to_size;
1995 int i, j = 0;
1996
1997 /* This is quite flexible, some examples:
1998 *
1999 * from_size == 0, to_size > 0, seed := csum --> pushing data
2000 * from_size > 0, to_size == 0, seed := csum --> pulling data
2001 * from_size > 0, to_size > 0, seed := 0 --> diffing data
2002 *
2003 * Even for diffing, from_size and to_size don't need to be equal.
2004 */
2005 if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
2006 diff_size > sizeof(sp->diff)))
2007 return -EINVAL;
2008
2009 for (i = 0; i < from_size / sizeof(__be32); i++, j++)
2010 sp->diff[j] = ~from[i];
2011 for (i = 0; i < to_size / sizeof(__be32); i++, j++)
2012 sp->diff[j] = to[i];
2013
2014 return csum_partial(sp->diff, diff_size, seed);
2015 }
2016
2017 static const struct bpf_func_proto bpf_csum_diff_proto = {
2018 .func = bpf_csum_diff,
2019 .gpl_only = false,
2020 .pkt_access = true,
2021 .ret_type = RET_INTEGER,
2022 .arg1_type = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2023 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
2024 .arg3_type = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2025 .arg4_type = ARG_CONST_SIZE_OR_ZERO,
2026 .arg5_type = ARG_ANYTHING,
2027 };
2028
BPF_CALL_2(bpf_csum_update,struct sk_buff *,skb,__wsum,csum)2029 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
2030 {
2031 /* The interface is to be used in combination with bpf_csum_diff()
2032 * for direct packet writes. csum rotation for alignment as well
2033 * as emulating csum_sub() can be done from the eBPF program.
2034 */
2035 if (skb->ip_summed == CHECKSUM_COMPLETE)
2036 return (skb->csum = csum_add(skb->csum, csum));
2037
2038 return -ENOTSUPP;
2039 }
2040
2041 static const struct bpf_func_proto bpf_csum_update_proto = {
2042 .func = bpf_csum_update,
2043 .gpl_only = false,
2044 .ret_type = RET_INTEGER,
2045 .arg1_type = ARG_PTR_TO_CTX,
2046 .arg2_type = ARG_ANYTHING,
2047 };
2048
BPF_CALL_2(bpf_csum_level,struct sk_buff *,skb,u64,level)2049 BPF_CALL_2(bpf_csum_level, struct sk_buff *, skb, u64, level)
2050 {
2051 /* The interface is to be used in combination with bpf_skb_adjust_room()
2052 * for encap/decap of packet headers when BPF_F_ADJ_ROOM_NO_CSUM_RESET
2053 * is passed as flags, for example.
2054 */
2055 switch (level) {
2056 case BPF_CSUM_LEVEL_INC:
2057 __skb_incr_checksum_unnecessary(skb);
2058 break;
2059 case BPF_CSUM_LEVEL_DEC:
2060 __skb_decr_checksum_unnecessary(skb);
2061 break;
2062 case BPF_CSUM_LEVEL_RESET:
2063 __skb_reset_checksum_unnecessary(skb);
2064 break;
2065 case BPF_CSUM_LEVEL_QUERY:
2066 return skb->ip_summed == CHECKSUM_UNNECESSARY ?
2067 skb->csum_level : -EACCES;
2068 default:
2069 return -EINVAL;
2070 }
2071
2072 return 0;
2073 }
2074
2075 static const struct bpf_func_proto bpf_csum_level_proto = {
2076 .func = bpf_csum_level,
2077 .gpl_only = false,
2078 .ret_type = RET_INTEGER,
2079 .arg1_type = ARG_PTR_TO_CTX,
2080 .arg2_type = ARG_ANYTHING,
2081 };
2082
__bpf_rx_skb(struct net_device * dev,struct sk_buff * skb)2083 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
2084 {
2085 return dev_forward_skb_nomtu(dev, skb);
2086 }
2087
__bpf_rx_skb_no_mac(struct net_device * dev,struct sk_buff * skb)2088 static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
2089 struct sk_buff *skb)
2090 {
2091 int ret = ____dev_forward_skb(dev, skb, false);
2092
2093 if (likely(!ret)) {
2094 skb->dev = dev;
2095 ret = netif_rx(skb);
2096 }
2097
2098 return ret;
2099 }
2100
__bpf_tx_skb(struct net_device * dev,struct sk_buff * skb)2101 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
2102 {
2103 int ret;
2104
2105 if (dev_xmit_recursion()) {
2106 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2107 kfree_skb(skb);
2108 return -ENETDOWN;
2109 }
2110
2111 skb->dev = dev;
2112 skb_clear_tstamp(skb);
2113
2114 dev_xmit_recursion_inc();
2115 ret = dev_queue_xmit(skb);
2116 dev_xmit_recursion_dec();
2117
2118 return ret;
2119 }
2120
__bpf_redirect_no_mac(struct sk_buff * skb,struct net_device * dev,u32 flags)2121 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
2122 u32 flags)
2123 {
2124 unsigned int mlen = skb_network_offset(skb);
2125
2126 if (mlen) {
2127 __skb_pull(skb, mlen);
2128
2129 /* At ingress, the mac header has already been pulled once.
2130 * At egress, skb_pospull_rcsum has to be done in case that
2131 * the skb is originated from ingress (i.e. a forwarded skb)
2132 * to ensure that rcsum starts at net header.
2133 */
2134 if (!skb_at_tc_ingress(skb))
2135 skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
2136 }
2137 skb_pop_mac_header(skb);
2138 skb_reset_mac_len(skb);
2139 return flags & BPF_F_INGRESS ?
2140 __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
2141 }
2142
__bpf_redirect_common(struct sk_buff * skb,struct net_device * dev,u32 flags)2143 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
2144 u32 flags)
2145 {
2146 /* Verify that a link layer header is carried */
2147 if (unlikely(skb->mac_header >= skb->network_header)) {
2148 kfree_skb(skb);
2149 return -ERANGE;
2150 }
2151
2152 bpf_push_mac_rcsum(skb);
2153 return flags & BPF_F_INGRESS ?
2154 __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
2155 }
2156
__bpf_redirect(struct sk_buff * skb,struct net_device * dev,u32 flags)2157 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
2158 u32 flags)
2159 {
2160 if (dev_is_mac_header_xmit(dev))
2161 return __bpf_redirect_common(skb, dev, flags);
2162 else
2163 return __bpf_redirect_no_mac(skb, dev, flags);
2164 }
2165
2166 #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)2167 static int bpf_out_neigh_v6(struct net *net, struct sk_buff *skb,
2168 struct net_device *dev, struct bpf_nh_params *nh)
2169 {
2170 u32 hh_len = LL_RESERVED_SPACE(dev);
2171 const struct in6_addr *nexthop;
2172 struct dst_entry *dst = NULL;
2173 struct neighbour *neigh;
2174
2175 if (dev_xmit_recursion()) {
2176 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2177 goto out_drop;
2178 }
2179
2180 skb->dev = dev;
2181 skb_clear_tstamp(skb);
2182
2183 if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
2184 skb = skb_expand_head(skb, hh_len);
2185 if (!skb)
2186 return -ENOMEM;
2187 }
2188
2189 rcu_read_lock_bh();
2190 if (!nh) {
2191 dst = skb_dst(skb);
2192 nexthop = rt6_nexthop(container_of(dst, struct rt6_info, dst),
2193 &ipv6_hdr(skb)->daddr);
2194 } else {
2195 nexthop = &nh->ipv6_nh;
2196 }
2197 neigh = ip_neigh_gw6(dev, nexthop);
2198 if (likely(!IS_ERR(neigh))) {
2199 int ret;
2200
2201 sock_confirm_neigh(skb, neigh);
2202 dev_xmit_recursion_inc();
2203 ret = neigh_output(neigh, skb, false);
2204 dev_xmit_recursion_dec();
2205 rcu_read_unlock_bh();
2206 return ret;
2207 }
2208 rcu_read_unlock_bh();
2209 if (dst)
2210 IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
2211 out_drop:
2212 kfree_skb(skb);
2213 return -ENETDOWN;
2214 }
2215
__bpf_redirect_neigh_v6(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2216 static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
2217 struct bpf_nh_params *nh)
2218 {
2219 const struct ipv6hdr *ip6h = ipv6_hdr(skb);
2220 struct net *net = dev_net(dev);
2221 int err, ret = NET_XMIT_DROP;
2222
2223 if (!nh) {
2224 struct dst_entry *dst;
2225 struct flowi6 fl6 = {
2226 .flowi6_flags = FLOWI_FLAG_ANYSRC,
2227 .flowi6_mark = skb->mark,
2228 .flowlabel = ip6_flowinfo(ip6h),
2229 .flowi6_oif = dev->ifindex,
2230 .flowi6_proto = ip6h->nexthdr,
2231 .daddr = ip6h->daddr,
2232 .saddr = ip6h->saddr,
2233 };
2234
2235 dst = ipv6_stub->ipv6_dst_lookup_flow(net, NULL, &fl6, NULL);
2236 if (IS_ERR(dst))
2237 goto out_drop;
2238
2239 skb_dst_set(skb, dst);
2240 } else if (nh->nh_family != AF_INET6) {
2241 goto out_drop;
2242 }
2243
2244 err = bpf_out_neigh_v6(net, skb, dev, nh);
2245 if (unlikely(net_xmit_eval(err)))
2246 dev->stats.tx_errors++;
2247 else
2248 ret = NET_XMIT_SUCCESS;
2249 goto out_xmit;
2250 out_drop:
2251 dev->stats.tx_errors++;
2252 kfree_skb(skb);
2253 out_xmit:
2254 return ret;
2255 }
2256 #else
__bpf_redirect_neigh_v6(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2257 static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
2258 struct bpf_nh_params *nh)
2259 {
2260 kfree_skb(skb);
2261 return NET_XMIT_DROP;
2262 }
2263 #endif /* CONFIG_IPV6 */
2264
2265 #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)2266 static int bpf_out_neigh_v4(struct net *net, struct sk_buff *skb,
2267 struct net_device *dev, struct bpf_nh_params *nh)
2268 {
2269 u32 hh_len = LL_RESERVED_SPACE(dev);
2270 struct neighbour *neigh;
2271 bool is_v6gw = false;
2272
2273 if (dev_xmit_recursion()) {
2274 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
2275 goto out_drop;
2276 }
2277
2278 skb->dev = dev;
2279 skb_clear_tstamp(skb);
2280
2281 if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) {
2282 skb = skb_expand_head(skb, hh_len);
2283 if (!skb)
2284 return -ENOMEM;
2285 }
2286
2287 rcu_read_lock_bh();
2288 if (!nh) {
2289 struct dst_entry *dst = skb_dst(skb);
2290 struct rtable *rt = container_of(dst, struct rtable, dst);
2291
2292 neigh = ip_neigh_for_gw(rt, skb, &is_v6gw);
2293 } else if (nh->nh_family == AF_INET6) {
2294 neigh = ip_neigh_gw6(dev, &nh->ipv6_nh);
2295 is_v6gw = true;
2296 } else if (nh->nh_family == AF_INET) {
2297 neigh = ip_neigh_gw4(dev, nh->ipv4_nh);
2298 } else {
2299 rcu_read_unlock_bh();
2300 goto out_drop;
2301 }
2302
2303 if (likely(!IS_ERR(neigh))) {
2304 int ret;
2305
2306 sock_confirm_neigh(skb, neigh);
2307 dev_xmit_recursion_inc();
2308 ret = neigh_output(neigh, skb, is_v6gw);
2309 dev_xmit_recursion_dec();
2310 rcu_read_unlock_bh();
2311 return ret;
2312 }
2313 rcu_read_unlock_bh();
2314 out_drop:
2315 kfree_skb(skb);
2316 return -ENETDOWN;
2317 }
2318
__bpf_redirect_neigh_v4(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2319 static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
2320 struct bpf_nh_params *nh)
2321 {
2322 const struct iphdr *ip4h = ip_hdr(skb);
2323 struct net *net = dev_net(dev);
2324 int err, ret = NET_XMIT_DROP;
2325
2326 if (!nh) {
2327 struct flowi4 fl4 = {
2328 .flowi4_flags = FLOWI_FLAG_ANYSRC,
2329 .flowi4_mark = skb->mark,
2330 .flowi4_tos = RT_TOS(ip4h->tos),
2331 .flowi4_oif = dev->ifindex,
2332 .flowi4_proto = ip4h->protocol,
2333 .daddr = ip4h->daddr,
2334 .saddr = ip4h->saddr,
2335 };
2336 struct rtable *rt;
2337
2338 rt = ip_route_output_flow(net, &fl4, NULL);
2339 if (IS_ERR(rt))
2340 goto out_drop;
2341 if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
2342 ip_rt_put(rt);
2343 goto out_drop;
2344 }
2345
2346 skb_dst_set(skb, &rt->dst);
2347 }
2348
2349 err = bpf_out_neigh_v4(net, skb, dev, nh);
2350 if (unlikely(net_xmit_eval(err)))
2351 dev->stats.tx_errors++;
2352 else
2353 ret = NET_XMIT_SUCCESS;
2354 goto out_xmit;
2355 out_drop:
2356 dev->stats.tx_errors++;
2357 kfree_skb(skb);
2358 out_xmit:
2359 return ret;
2360 }
2361 #else
__bpf_redirect_neigh_v4(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2362 static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
2363 struct bpf_nh_params *nh)
2364 {
2365 kfree_skb(skb);
2366 return NET_XMIT_DROP;
2367 }
2368 #endif /* CONFIG_INET */
2369
__bpf_redirect_neigh(struct sk_buff * skb,struct net_device * dev,struct bpf_nh_params * nh)2370 static int __bpf_redirect_neigh(struct sk_buff *skb, struct net_device *dev,
2371 struct bpf_nh_params *nh)
2372 {
2373 struct ethhdr *ethh = eth_hdr(skb);
2374
2375 if (unlikely(skb->mac_header >= skb->network_header))
2376 goto out;
2377 bpf_push_mac_rcsum(skb);
2378 if (is_multicast_ether_addr(ethh->h_dest))
2379 goto out;
2380
2381 skb_pull(skb, sizeof(*ethh));
2382 skb_unset_mac_header(skb);
2383 skb_reset_network_header(skb);
2384
2385 if (skb->protocol == htons(ETH_P_IP))
2386 return __bpf_redirect_neigh_v4(skb, dev, nh);
2387 else if (skb->protocol == htons(ETH_P_IPV6))
2388 return __bpf_redirect_neigh_v6(skb, dev, nh);
2389 out:
2390 kfree_skb(skb);
2391 return -ENOTSUPP;
2392 }
2393
2394 /* Internal, non-exposed redirect flags. */
2395 enum {
2396 BPF_F_NEIGH = (1ULL << 1),
2397 BPF_F_PEER = (1ULL << 2),
2398 BPF_F_NEXTHOP = (1ULL << 3),
2399 #define BPF_F_REDIRECT_INTERNAL (BPF_F_NEIGH | BPF_F_PEER | BPF_F_NEXTHOP)
2400 };
2401
BPF_CALL_3(bpf_clone_redirect,struct sk_buff *,skb,u32,ifindex,u64,flags)2402 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
2403 {
2404 struct net_device *dev;
2405 struct sk_buff *clone;
2406 int ret;
2407
2408 if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
2409 return -EINVAL;
2410
2411 dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
2412 if (unlikely(!dev))
2413 return -EINVAL;
2414
2415 clone = skb_clone(skb, GFP_ATOMIC);
2416 if (unlikely(!clone))
2417 return -ENOMEM;
2418
2419 /* For direct write, we need to keep the invariant that the skbs
2420 * we're dealing with need to be uncloned. Should uncloning fail
2421 * here, we need to free the just generated clone to unclone once
2422 * again.
2423 */
2424 ret = bpf_try_make_head_writable(skb);
2425 if (unlikely(ret)) {
2426 kfree_skb(clone);
2427 return -ENOMEM;
2428 }
2429
2430 return __bpf_redirect(clone, dev, flags);
2431 }
2432
2433 static const struct bpf_func_proto bpf_clone_redirect_proto = {
2434 .func = bpf_clone_redirect,
2435 .gpl_only = false,
2436 .ret_type = RET_INTEGER,
2437 .arg1_type = ARG_PTR_TO_CTX,
2438 .arg2_type = ARG_ANYTHING,
2439 .arg3_type = ARG_ANYTHING,
2440 };
2441
2442 DEFINE_PER_CPU(struct bpf_redirect_info, bpf_redirect_info);
2443 EXPORT_PER_CPU_SYMBOL_GPL(bpf_redirect_info);
2444
skb_do_redirect(struct sk_buff * skb)2445 int skb_do_redirect(struct sk_buff *skb)
2446 {
2447 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2448 struct net *net = dev_net(skb->dev);
2449 struct net_device *dev;
2450 u32 flags = ri->flags;
2451
2452 dev = dev_get_by_index_rcu(net, ri->tgt_index);
2453 ri->tgt_index = 0;
2454 ri->flags = 0;
2455 if (unlikely(!dev))
2456 goto out_drop;
2457 if (flags & BPF_F_PEER) {
2458 const struct net_device_ops *ops = dev->netdev_ops;
2459
2460 if (unlikely(!ops->ndo_get_peer_dev ||
2461 !skb_at_tc_ingress(skb)))
2462 goto out_drop;
2463 dev = ops->ndo_get_peer_dev(dev);
2464 if (unlikely(!dev ||
2465 !(dev->flags & IFF_UP) ||
2466 net_eq(net, dev_net(dev))))
2467 goto out_drop;
2468 skb->dev = dev;
2469 return -EAGAIN;
2470 }
2471 return flags & BPF_F_NEIGH ?
2472 __bpf_redirect_neigh(skb, dev, flags & BPF_F_NEXTHOP ?
2473 &ri->nh : NULL) :
2474 __bpf_redirect(skb, dev, flags);
2475 out_drop:
2476 kfree_skb(skb);
2477 return -EINVAL;
2478 }
2479
BPF_CALL_2(bpf_redirect,u32,ifindex,u64,flags)2480 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
2481 {
2482 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2483
2484 if (unlikely(flags & (~(BPF_F_INGRESS) | BPF_F_REDIRECT_INTERNAL)))
2485 return TC_ACT_SHOT;
2486
2487 ri->flags = flags;
2488 ri->tgt_index = ifindex;
2489
2490 return TC_ACT_REDIRECT;
2491 }
2492
2493 static const struct bpf_func_proto bpf_redirect_proto = {
2494 .func = bpf_redirect,
2495 .gpl_only = false,
2496 .ret_type = RET_INTEGER,
2497 .arg1_type = ARG_ANYTHING,
2498 .arg2_type = ARG_ANYTHING,
2499 };
2500
BPF_CALL_2(bpf_redirect_peer,u32,ifindex,u64,flags)2501 BPF_CALL_2(bpf_redirect_peer, u32, ifindex, u64, flags)
2502 {
2503 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2504
2505 if (unlikely(flags))
2506 return TC_ACT_SHOT;
2507
2508 ri->flags = BPF_F_PEER;
2509 ri->tgt_index = ifindex;
2510
2511 return TC_ACT_REDIRECT;
2512 }
2513
2514 static const struct bpf_func_proto bpf_redirect_peer_proto = {
2515 .func = bpf_redirect_peer,
2516 .gpl_only = false,
2517 .ret_type = RET_INTEGER,
2518 .arg1_type = ARG_ANYTHING,
2519 .arg2_type = ARG_ANYTHING,
2520 };
2521
BPF_CALL_4(bpf_redirect_neigh,u32,ifindex,struct bpf_redir_neigh *,params,int,plen,u64,flags)2522 BPF_CALL_4(bpf_redirect_neigh, u32, ifindex, struct bpf_redir_neigh *, params,
2523 int, plen, u64, flags)
2524 {
2525 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
2526
2527 if (unlikely((plen && plen < sizeof(*params)) || flags))
2528 return TC_ACT_SHOT;
2529
2530 ri->flags = BPF_F_NEIGH | (plen ? BPF_F_NEXTHOP : 0);
2531 ri->tgt_index = ifindex;
2532
2533 BUILD_BUG_ON(sizeof(struct bpf_redir_neigh) != sizeof(struct bpf_nh_params));
2534 if (plen)
2535 memcpy(&ri->nh, params, sizeof(ri->nh));
2536
2537 return TC_ACT_REDIRECT;
2538 }
2539
2540 static const struct bpf_func_proto bpf_redirect_neigh_proto = {
2541 .func = bpf_redirect_neigh,
2542 .gpl_only = false,
2543 .ret_type = RET_INTEGER,
2544 .arg1_type = ARG_ANYTHING,
2545 .arg2_type = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
2546 .arg3_type = ARG_CONST_SIZE_OR_ZERO,
2547 .arg4_type = ARG_ANYTHING,
2548 };
2549
BPF_CALL_2(bpf_msg_apply_bytes,struct sk_msg *,msg,u32,bytes)2550 BPF_CALL_2(bpf_msg_apply_bytes, struct sk_msg *, msg, u32, bytes)
2551 {
2552 msg->apply_bytes = bytes;
2553 return 0;
2554 }
2555
2556 static const struct bpf_func_proto bpf_msg_apply_bytes_proto = {
2557 .func = bpf_msg_apply_bytes,
2558 .gpl_only = false,
2559 .ret_type = RET_INTEGER,
2560 .arg1_type = ARG_PTR_TO_CTX,
2561 .arg2_type = ARG_ANYTHING,
2562 };
2563
BPF_CALL_2(bpf_msg_cork_bytes,struct sk_msg *,msg,u32,bytes)2564 BPF_CALL_2(bpf_msg_cork_bytes, struct sk_msg *, msg, u32, bytes)
2565 {
2566 msg->cork_bytes = bytes;
2567 return 0;
2568 }
2569
2570 static const struct bpf_func_proto bpf_msg_cork_bytes_proto = {
2571 .func = bpf_msg_cork_bytes,
2572 .gpl_only = false,
2573 .ret_type = RET_INTEGER,
2574 .arg1_type = ARG_PTR_TO_CTX,
2575 .arg2_type = ARG_ANYTHING,
2576 };
2577
BPF_CALL_4(bpf_msg_pull_data,struct sk_msg *,msg,u32,start,u32,end,u64,flags)2578 BPF_CALL_4(bpf_msg_pull_data, struct sk_msg *, msg, u32, start,
2579 u32, end, u64, flags)
2580 {
2581 u32 len = 0, offset = 0, copy = 0, poffset = 0, bytes = end - start;
2582 u32 first_sge, last_sge, i, shift, bytes_sg_total;
2583 struct scatterlist *sge;
2584 u8 *raw, *to, *from;
2585 struct page *page;
2586
2587 if (unlikely(flags || end <= start))
2588 return -EINVAL;
2589
2590 /* First find the starting scatterlist element */
2591 i = msg->sg.start;
2592 do {
2593 offset += len;
2594 len = sk_msg_elem(msg, i)->length;
2595 if (start < offset + len)
2596 break;
2597 sk_msg_iter_var_next(i);
2598 } while (i != msg->sg.end);
2599
2600 if (unlikely(start >= offset + len))
2601 return -EINVAL;
2602
2603 first_sge = i;
2604 /* The start may point into the sg element so we need to also
2605 * account for the headroom.
2606 */
2607 bytes_sg_total = start - offset + bytes;
2608 if (!test_bit(i, msg->sg.copy) && bytes_sg_total <= len)
2609 goto out;
2610
2611 /* At this point we need to linearize multiple scatterlist
2612 * elements or a single shared page. Either way we need to
2613 * copy into a linear buffer exclusively owned by BPF. Then
2614 * place the buffer in the scatterlist and fixup the original
2615 * entries by removing the entries now in the linear buffer
2616 * and shifting the remaining entries. For now we do not try
2617 * to copy partial entries to avoid complexity of running out
2618 * of sg_entry slots. The downside is reading a single byte
2619 * will copy the entire sg entry.
2620 */
2621 do {
2622 copy += sk_msg_elem(msg, i)->length;
2623 sk_msg_iter_var_next(i);
2624 if (bytes_sg_total <= copy)
2625 break;
2626 } while (i != msg->sg.end);
2627 last_sge = i;
2628
2629 if (unlikely(bytes_sg_total > copy))
2630 return -EINVAL;
2631
2632 page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2633 get_order(copy));
2634 if (unlikely(!page))
2635 return -ENOMEM;
2636
2637 raw = page_address(page);
2638 i = first_sge;
2639 do {
2640 sge = sk_msg_elem(msg, i);
2641 from = sg_virt(sge);
2642 len = sge->length;
2643 to = raw + poffset;
2644
2645 memcpy(to, from, len);
2646 poffset += len;
2647 sge->length = 0;
2648 put_page(sg_page(sge));
2649
2650 sk_msg_iter_var_next(i);
2651 } while (i != last_sge);
2652
2653 sg_set_page(&msg->sg.data[first_sge], page, copy, 0);
2654
2655 /* To repair sg ring we need to shift entries. If we only
2656 * had a single entry though we can just replace it and
2657 * be done. Otherwise walk the ring and shift the entries.
2658 */
2659 WARN_ON_ONCE(last_sge == first_sge);
2660 shift = last_sge > first_sge ?
2661 last_sge - first_sge - 1 :
2662 NR_MSG_FRAG_IDS - first_sge + last_sge - 1;
2663 if (!shift)
2664 goto out;
2665
2666 i = first_sge;
2667 sk_msg_iter_var_next(i);
2668 do {
2669 u32 move_from;
2670
2671 if (i + shift >= NR_MSG_FRAG_IDS)
2672 move_from = i + shift - NR_MSG_FRAG_IDS;
2673 else
2674 move_from = i + shift;
2675 if (move_from == msg->sg.end)
2676 break;
2677
2678 msg->sg.data[i] = msg->sg.data[move_from];
2679 msg->sg.data[move_from].length = 0;
2680 msg->sg.data[move_from].page_link = 0;
2681 msg->sg.data[move_from].offset = 0;
2682 sk_msg_iter_var_next(i);
2683 } while (1);
2684
2685 msg->sg.end = msg->sg.end - shift > msg->sg.end ?
2686 msg->sg.end - shift + NR_MSG_FRAG_IDS :
2687 msg->sg.end - shift;
2688 out:
2689 msg->data = sg_virt(&msg->sg.data[first_sge]) + start - offset;
2690 msg->data_end = msg->data + bytes;
2691 return 0;
2692 }
2693
2694 static const struct bpf_func_proto bpf_msg_pull_data_proto = {
2695 .func = bpf_msg_pull_data,
2696 .gpl_only = false,
2697 .ret_type = RET_INTEGER,
2698 .arg1_type = ARG_PTR_TO_CTX,
2699 .arg2_type = ARG_ANYTHING,
2700 .arg3_type = ARG_ANYTHING,
2701 .arg4_type = ARG_ANYTHING,
2702 };
2703
BPF_CALL_4(bpf_msg_push_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2704 BPF_CALL_4(bpf_msg_push_data, struct sk_msg *, msg, u32, start,
2705 u32, len, u64, flags)
2706 {
2707 struct scatterlist sge, nsge, nnsge, rsge = {0}, *psge;
2708 u32 new, i = 0, l = 0, space, copy = 0, offset = 0;
2709 u8 *raw, *to, *from;
2710 struct page *page;
2711
2712 if (unlikely(flags))
2713 return -EINVAL;
2714
2715 if (unlikely(len == 0))
2716 return 0;
2717
2718 /* First find the starting scatterlist element */
2719 i = msg->sg.start;
2720 do {
2721 offset += l;
2722 l = sk_msg_elem(msg, i)->length;
2723
2724 if (start < offset + l)
2725 break;
2726 sk_msg_iter_var_next(i);
2727 } while (i != msg->sg.end);
2728
2729 if (start >= offset + l)
2730 return -EINVAL;
2731
2732 space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2733
2734 /* If no space available will fallback to copy, we need at
2735 * least one scatterlist elem available to push data into
2736 * when start aligns to the beginning of an element or two
2737 * when it falls inside an element. We handle the start equals
2738 * offset case because its the common case for inserting a
2739 * header.
2740 */
2741 if (!space || (space == 1 && start != offset))
2742 copy = msg->sg.data[i].length;
2743
2744 page = alloc_pages(__GFP_NOWARN | GFP_ATOMIC | __GFP_COMP,
2745 get_order(copy + len));
2746 if (unlikely(!page))
2747 return -ENOMEM;
2748
2749 if (copy) {
2750 int front, back;
2751
2752 raw = page_address(page);
2753
2754 psge = sk_msg_elem(msg, i);
2755 front = start - offset;
2756 back = psge->length - front;
2757 from = sg_virt(psge);
2758
2759 if (front)
2760 memcpy(raw, from, front);
2761
2762 if (back) {
2763 from += front;
2764 to = raw + front + len;
2765
2766 memcpy(to, from, back);
2767 }
2768
2769 put_page(sg_page(psge));
2770 } else if (start - offset) {
2771 psge = sk_msg_elem(msg, i);
2772 rsge = sk_msg_elem_cpy(msg, i);
2773
2774 psge->length = start - offset;
2775 rsge.length -= psge->length;
2776 rsge.offset += start;
2777
2778 sk_msg_iter_var_next(i);
2779 sg_unmark_end(psge);
2780 sg_unmark_end(&rsge);
2781 sk_msg_iter_next(msg, end);
2782 }
2783
2784 /* Slot(s) to place newly allocated data */
2785 new = i;
2786
2787 /* Shift one or two slots as needed */
2788 if (!copy) {
2789 sge = sk_msg_elem_cpy(msg, i);
2790
2791 sk_msg_iter_var_next(i);
2792 sg_unmark_end(&sge);
2793 sk_msg_iter_next(msg, end);
2794
2795 nsge = sk_msg_elem_cpy(msg, i);
2796 if (rsge.length) {
2797 sk_msg_iter_var_next(i);
2798 nnsge = sk_msg_elem_cpy(msg, i);
2799 }
2800
2801 while (i != msg->sg.end) {
2802 msg->sg.data[i] = sge;
2803 sge = nsge;
2804 sk_msg_iter_var_next(i);
2805 if (rsge.length) {
2806 nsge = nnsge;
2807 nnsge = sk_msg_elem_cpy(msg, i);
2808 } else {
2809 nsge = sk_msg_elem_cpy(msg, i);
2810 }
2811 }
2812 }
2813
2814 /* Place newly allocated data buffer */
2815 sk_mem_charge(msg->sk, len);
2816 msg->sg.size += len;
2817 __clear_bit(new, msg->sg.copy);
2818 sg_set_page(&msg->sg.data[new], page, len + copy, 0);
2819 if (rsge.length) {
2820 get_page(sg_page(&rsge));
2821 sk_msg_iter_var_next(new);
2822 msg->sg.data[new] = rsge;
2823 }
2824
2825 sk_msg_compute_data_pointers(msg);
2826 return 0;
2827 }
2828
2829 static const struct bpf_func_proto bpf_msg_push_data_proto = {
2830 .func = bpf_msg_push_data,
2831 .gpl_only = false,
2832 .ret_type = RET_INTEGER,
2833 .arg1_type = ARG_PTR_TO_CTX,
2834 .arg2_type = ARG_ANYTHING,
2835 .arg3_type = ARG_ANYTHING,
2836 .arg4_type = ARG_ANYTHING,
2837 };
2838
sk_msg_shift_left(struct sk_msg * msg,int i)2839 static void sk_msg_shift_left(struct sk_msg *msg, int i)
2840 {
2841 int prev;
2842
2843 do {
2844 prev = i;
2845 sk_msg_iter_var_next(i);
2846 msg->sg.data[prev] = msg->sg.data[i];
2847 } while (i != msg->sg.end);
2848
2849 sk_msg_iter_prev(msg, end);
2850 }
2851
sk_msg_shift_right(struct sk_msg * msg,int i)2852 static void sk_msg_shift_right(struct sk_msg *msg, int i)
2853 {
2854 struct scatterlist tmp, sge;
2855
2856 sk_msg_iter_next(msg, end);
2857 sge = sk_msg_elem_cpy(msg, i);
2858 sk_msg_iter_var_next(i);
2859 tmp = sk_msg_elem_cpy(msg, i);
2860
2861 while (i != msg->sg.end) {
2862 msg->sg.data[i] = sge;
2863 sk_msg_iter_var_next(i);
2864 sge = tmp;
2865 tmp = sk_msg_elem_cpy(msg, i);
2866 }
2867 }
2868
BPF_CALL_4(bpf_msg_pop_data,struct sk_msg *,msg,u32,start,u32,len,u64,flags)2869 BPF_CALL_4(bpf_msg_pop_data, struct sk_msg *, msg, u32, start,
2870 u32, len, u64, flags)
2871 {
2872 u32 i = 0, l = 0, space, offset = 0;
2873 u64 last = start + len;
2874 int pop;
2875
2876 if (unlikely(flags))
2877 return -EINVAL;
2878
2879 /* First find the starting scatterlist element */
2880 i = msg->sg.start;
2881 do {
2882 offset += l;
2883 l = sk_msg_elem(msg, i)->length;
2884
2885 if (start < offset + l)
2886 break;
2887 sk_msg_iter_var_next(i);
2888 } while (i != msg->sg.end);
2889
2890 /* Bounds checks: start and pop must be inside message */
2891 if (start >= offset + l || last >= msg->sg.size)
2892 return -EINVAL;
2893
2894 space = MAX_MSG_FRAGS - sk_msg_elem_used(msg);
2895
2896 pop = len;
2897 /* --------------| offset
2898 * -| start |-------- len -------|
2899 *
2900 * |----- a ----|-------- pop -------|----- b ----|
2901 * |______________________________________________| length
2902 *
2903 *
2904 * a: region at front of scatter element to save
2905 * b: region at back of scatter element to save when length > A + pop
2906 * pop: region to pop from element, same as input 'pop' here will be
2907 * decremented below per iteration.
2908 *
2909 * Two top-level cases to handle when start != offset, first B is non
2910 * zero and second B is zero corresponding to when a pop includes more
2911 * than one element.
2912 *
2913 * Then if B is non-zero AND there is no space allocate space and
2914 * compact A, B regions into page. If there is space shift ring to
2915 * the rigth free'ing the next element in ring to place B, leaving
2916 * A untouched except to reduce length.
2917 */
2918 if (start != offset) {
2919 struct scatterlist *nsge, *sge = sk_msg_elem(msg, i);
2920 int a = start;
2921 int b = sge->length - pop - a;
2922
2923 sk_msg_iter_var_next(i);
2924
2925 if (pop < sge->length - a) {
2926 if (space) {
2927 sge->length = a;
2928 sk_msg_shift_right(msg, i);
2929 nsge = sk_msg_elem(msg, i);
2930 get_page(sg_page(sge));
2931 sg_set_page(nsge,
2932 sg_page(sge),
2933 b, sge->offset + pop + a);
2934 } else {
2935 struct page *page, *orig;
2936 u8 *to, *from;
2937
2938 page = alloc_pages(__GFP_NOWARN |
2939 __GFP_COMP | GFP_ATOMIC,
2940 get_order(a + b));
2941 if (unlikely(!page))
2942 return -ENOMEM;
2943
2944 sge->length = a;
2945 orig = sg_page(sge);
2946 from = sg_virt(sge);
2947 to = page_address(page);
2948 memcpy(to, from, a);
2949 memcpy(to + a, from + a + pop, b);
2950 sg_set_page(sge, page, a + b, 0);
2951 put_page(orig);
2952 }
2953 pop = 0;
2954 } else if (pop >= sge->length - a) {
2955 pop -= (sge->length - a);
2956 sge->length = a;
2957 }
2958 }
2959
2960 /* From above the current layout _must_ be as follows,
2961 *
2962 * -| offset
2963 * -| start
2964 *
2965 * |---- pop ---|---------------- b ------------|
2966 * |____________________________________________| length
2967 *
2968 * Offset and start of the current msg elem are equal because in the
2969 * previous case we handled offset != start and either consumed the
2970 * entire element and advanced to the next element OR pop == 0.
2971 *
2972 * Two cases to handle here are first pop is less than the length
2973 * leaving some remainder b above. Simply adjust the element's layout
2974 * in this case. Or pop >= length of the element so that b = 0. In this
2975 * case advance to next element decrementing pop.
2976 */
2977 while (pop) {
2978 struct scatterlist *sge = sk_msg_elem(msg, i);
2979
2980 if (pop < sge->length) {
2981 sge->length -= pop;
2982 sge->offset += pop;
2983 pop = 0;
2984 } else {
2985 pop -= sge->length;
2986 sk_msg_shift_left(msg, i);
2987 }
2988 sk_msg_iter_var_next(i);
2989 }
2990
2991 sk_mem_uncharge(msg->sk, len - pop);
2992 msg->sg.size -= (len - pop);
2993 sk_msg_compute_data_pointers(msg);
2994 return 0;
2995 }
2996
2997 static const struct bpf_func_proto bpf_msg_pop_data_proto = {
2998 .func = bpf_msg_pop_data,
2999 .gpl_only = false,
3000 .ret_type = RET_INTEGER,
3001 .arg1_type = ARG_PTR_TO_CTX,
3002 .arg2_type = ARG_ANYTHING,
3003 .arg3_type = ARG_ANYTHING,
3004 .arg4_type = ARG_ANYTHING,
3005 };
3006
3007 #ifdef CONFIG_CGROUP_NET_CLASSID
BPF_CALL_0(bpf_get_cgroup_classid_curr)3008 BPF_CALL_0(bpf_get_cgroup_classid_curr)
3009 {
3010 return __task_get_classid(current);
3011 }
3012
3013 static const struct bpf_func_proto bpf_get_cgroup_classid_curr_proto = {
3014 .func = bpf_get_cgroup_classid_curr,
3015 .gpl_only = false,
3016 .ret_type = RET_INTEGER,
3017 };
3018
BPF_CALL_1(bpf_skb_cgroup_classid,const struct sk_buff *,skb)3019 BPF_CALL_1(bpf_skb_cgroup_classid, const struct sk_buff *, skb)
3020 {
3021 struct sock *sk = skb_to_full_sk(skb);
3022
3023 if (!sk || !sk_fullsock(sk))
3024 return 0;
3025
3026 return sock_cgroup_classid(&sk->sk_cgrp_data);
3027 }
3028
3029 static const struct bpf_func_proto bpf_skb_cgroup_classid_proto = {
3030 .func = bpf_skb_cgroup_classid,
3031 .gpl_only = false,
3032 .ret_type = RET_INTEGER,
3033 .arg1_type = ARG_PTR_TO_CTX,
3034 };
3035 #endif
3036
BPF_CALL_1(bpf_get_cgroup_classid,const struct sk_buff *,skb)3037 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
3038 {
3039 return task_get_classid(skb);
3040 }
3041
3042 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
3043 .func = bpf_get_cgroup_classid,
3044 .gpl_only = false,
3045 .ret_type = RET_INTEGER,
3046 .arg1_type = ARG_PTR_TO_CTX,
3047 };
3048
BPF_CALL_1(bpf_get_route_realm,const struct sk_buff *,skb)3049 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
3050 {
3051 return dst_tclassid(skb);
3052 }
3053
3054 static const struct bpf_func_proto bpf_get_route_realm_proto = {
3055 .func = bpf_get_route_realm,
3056 .gpl_only = false,
3057 .ret_type = RET_INTEGER,
3058 .arg1_type = ARG_PTR_TO_CTX,
3059 };
3060
BPF_CALL_1(bpf_get_hash_recalc,struct sk_buff *,skb)3061 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
3062 {
3063 /* If skb_clear_hash() was called due to mangling, we can
3064 * trigger SW recalculation here. Later access to hash
3065 * can then use the inline skb->hash via context directly
3066 * instead of calling this helper again.
3067 */
3068 return skb_get_hash(skb);
3069 }
3070
3071 static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
3072 .func = bpf_get_hash_recalc,
3073 .gpl_only = false,
3074 .ret_type = RET_INTEGER,
3075 .arg1_type = ARG_PTR_TO_CTX,
3076 };
3077
BPF_CALL_1(bpf_set_hash_invalid,struct sk_buff *,skb)3078 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
3079 {
3080 /* After all direct packet write, this can be used once for
3081 * triggering a lazy recalc on next skb_get_hash() invocation.
3082 */
3083 skb_clear_hash(skb);
3084 return 0;
3085 }
3086
3087 static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
3088 .func = bpf_set_hash_invalid,
3089 .gpl_only = false,
3090 .ret_type = RET_INTEGER,
3091 .arg1_type = ARG_PTR_TO_CTX,
3092 };
3093
BPF_CALL_2(bpf_set_hash,struct sk_buff *,skb,u32,hash)3094 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
3095 {
3096 /* Set user specified hash as L4(+), so that it gets returned
3097 * on skb_get_hash() call unless BPF prog later on triggers a
3098 * skb_clear_hash().
3099 */
3100 __skb_set_sw_hash(skb, hash, true);
3101 return 0;
3102 }
3103
3104 static const struct bpf_func_proto bpf_set_hash_proto = {
3105 .func = bpf_set_hash,
3106 .gpl_only = false,
3107 .ret_type = RET_INTEGER,
3108 .arg1_type = ARG_PTR_TO_CTX,
3109 .arg2_type = ARG_ANYTHING,
3110 };
3111
BPF_CALL_3(bpf_skb_vlan_push,struct sk_buff *,skb,__be16,vlan_proto,u16,vlan_tci)3112 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
3113 u16, vlan_tci)
3114 {
3115 int ret;
3116
3117 if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
3118 vlan_proto != htons(ETH_P_8021AD)))
3119 vlan_proto = htons(ETH_P_8021Q);
3120
3121 bpf_push_mac_rcsum(skb);
3122 ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
3123 bpf_pull_mac_rcsum(skb);
3124
3125 bpf_compute_data_pointers(skb);
3126 return ret;
3127 }
3128
3129 static const struct bpf_func_proto bpf_skb_vlan_push_proto = {
3130 .func = bpf_skb_vlan_push,
3131 .gpl_only = false,
3132 .ret_type = RET_INTEGER,
3133 .arg1_type = ARG_PTR_TO_CTX,
3134 .arg2_type = ARG_ANYTHING,
3135 .arg3_type = ARG_ANYTHING,
3136 };
3137
BPF_CALL_1(bpf_skb_vlan_pop,struct sk_buff *,skb)3138 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
3139 {
3140 int ret;
3141
3142 bpf_push_mac_rcsum(skb);
3143 ret = skb_vlan_pop(skb);
3144 bpf_pull_mac_rcsum(skb);
3145
3146 bpf_compute_data_pointers(skb);
3147 return ret;
3148 }
3149
3150 static const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
3151 .func = bpf_skb_vlan_pop,
3152 .gpl_only = false,
3153 .ret_type = RET_INTEGER,
3154 .arg1_type = ARG_PTR_TO_CTX,
3155 };
3156
bpf_skb_generic_push(struct sk_buff * skb,u32 off,u32 len)3157 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
3158 {
3159 /* Caller already did skb_cow() with len as headroom,
3160 * so no need to do it here.
3161 */
3162 skb_push(skb, len);
3163 memmove(skb->data, skb->data + len, off);
3164 memset(skb->data + off, 0, len);
3165
3166 /* No skb_postpush_rcsum(skb, skb->data + off, len)
3167 * needed here as it does not change the skb->csum
3168 * result for checksum complete when summing over
3169 * zeroed blocks.
3170 */
3171 return 0;
3172 }
3173
bpf_skb_generic_pop(struct sk_buff * skb,u32 off,u32 len)3174 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
3175 {
3176 /* skb_ensure_writable() is not needed here, as we're
3177 * already working on an uncloned skb.
3178 */
3179 if (unlikely(!pskb_may_pull(skb, off + len)))
3180 return -ENOMEM;
3181
3182 skb_postpull_rcsum(skb, skb->data + off, len);
3183 memmove(skb->data + len, skb->data, off);
3184 __skb_pull(skb, len);
3185
3186 return 0;
3187 }
3188
bpf_skb_net_hdr_push(struct sk_buff * skb,u32 off,u32 len)3189 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
3190 {
3191 bool trans_same = skb->transport_header == skb->network_header;
3192 int ret;
3193
3194 /* There's no need for __skb_push()/__skb_pull() pair to
3195 * get to the start of the mac header as we're guaranteed
3196 * to always start from here under eBPF.
3197 */
3198 ret = bpf_skb_generic_push(skb, off, len);
3199 if (likely(!ret)) {
3200 skb->mac_header -= len;
3201 skb->network_header -= len;
3202 if (trans_same)
3203 skb->transport_header = skb->network_header;
3204 }
3205
3206 return ret;
3207 }
3208
bpf_skb_net_hdr_pop(struct sk_buff * skb,u32 off,u32 len)3209 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
3210 {
3211 bool trans_same = skb->transport_header == skb->network_header;
3212 int ret;
3213
3214 /* Same here, __skb_push()/__skb_pull() pair not needed. */
3215 ret = bpf_skb_generic_pop(skb, off, len);
3216 if (likely(!ret)) {
3217 skb->mac_header += len;
3218 skb->network_header += len;
3219 if (trans_same)
3220 skb->transport_header = skb->network_header;
3221 }
3222
3223 return ret;
3224 }
3225
bpf_skb_proto_4_to_6(struct sk_buff * skb)3226 static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
3227 {
3228 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
3229 u32 off = skb_mac_header_len(skb);
3230 int ret;
3231
3232 ret = skb_cow(skb, len_diff);
3233 if (unlikely(ret < 0))
3234 return ret;
3235
3236 ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3237 if (unlikely(ret < 0))
3238 return ret;
3239
3240 if (skb_is_gso(skb)) {
3241 struct skb_shared_info *shinfo = skb_shinfo(skb);
3242
3243 /* SKB_GSO_TCPV4 needs to be changed into SKB_GSO_TCPV6. */
3244 if (shinfo->gso_type & SKB_GSO_TCPV4) {
3245 shinfo->gso_type &= ~SKB_GSO_TCPV4;
3246 shinfo->gso_type |= SKB_GSO_TCPV6;
3247 }
3248 }
3249
3250 skb->protocol = htons(ETH_P_IPV6);
3251 skb_clear_hash(skb);
3252
3253 return 0;
3254 }
3255
bpf_skb_proto_6_to_4(struct sk_buff * skb)3256 static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
3257 {
3258 const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
3259 u32 off = skb_mac_header_len(skb);
3260 int ret;
3261
3262 ret = skb_unclone(skb, GFP_ATOMIC);
3263 if (unlikely(ret < 0))
3264 return ret;
3265
3266 ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3267 if (unlikely(ret < 0))
3268 return ret;
3269
3270 if (skb_is_gso(skb)) {
3271 struct skb_shared_info *shinfo = skb_shinfo(skb);
3272
3273 /* SKB_GSO_TCPV6 needs to be changed into SKB_GSO_TCPV4. */
3274 if (shinfo->gso_type & SKB_GSO_TCPV6) {
3275 shinfo->gso_type &= ~SKB_GSO_TCPV6;
3276 shinfo->gso_type |= SKB_GSO_TCPV4;
3277 }
3278 }
3279
3280 skb->protocol = htons(ETH_P_IP);
3281 skb_clear_hash(skb);
3282
3283 return 0;
3284 }
3285
bpf_skb_proto_xlat(struct sk_buff * skb,__be16 to_proto)3286 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
3287 {
3288 __be16 from_proto = skb->protocol;
3289
3290 if (from_proto == htons(ETH_P_IP) &&
3291 to_proto == htons(ETH_P_IPV6))
3292 return bpf_skb_proto_4_to_6(skb);
3293
3294 if (from_proto == htons(ETH_P_IPV6) &&
3295 to_proto == htons(ETH_P_IP))
3296 return bpf_skb_proto_6_to_4(skb);
3297
3298 return -ENOTSUPP;
3299 }
3300
BPF_CALL_3(bpf_skb_change_proto,struct sk_buff *,skb,__be16,proto,u64,flags)3301 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
3302 u64, flags)
3303 {
3304 int ret;
3305
3306 if (unlikely(flags))
3307 return -EINVAL;
3308
3309 /* General idea is that this helper does the basic groundwork
3310 * needed for changing the protocol, and eBPF program fills the
3311 * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
3312 * and other helpers, rather than passing a raw buffer here.
3313 *
3314 * The rationale is to keep this minimal and without a need to
3315 * deal with raw packet data. F.e. even if we would pass buffers
3316 * here, the program still needs to call the bpf_lX_csum_replace()
3317 * helpers anyway. Plus, this way we keep also separation of
3318 * concerns, since f.e. bpf_skb_store_bytes() should only take
3319 * care of stores.
3320 *
3321 * Currently, additional options and extension header space are
3322 * not supported, but flags register is reserved so we can adapt
3323 * that. For offloads, we mark packet as dodgy, so that headers
3324 * need to be verified first.
3325 */
3326 ret = bpf_skb_proto_xlat(skb, proto);
3327 bpf_compute_data_pointers(skb);
3328 return ret;
3329 }
3330
3331 static const struct bpf_func_proto bpf_skb_change_proto_proto = {
3332 .func = bpf_skb_change_proto,
3333 .gpl_only = false,
3334 .ret_type = RET_INTEGER,
3335 .arg1_type = ARG_PTR_TO_CTX,
3336 .arg2_type = ARG_ANYTHING,
3337 .arg3_type = ARG_ANYTHING,
3338 };
3339
BPF_CALL_2(bpf_skb_change_type,struct sk_buff *,skb,u32,pkt_type)3340 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
3341 {
3342 /* We only allow a restricted subset to be changed for now. */
3343 if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
3344 !skb_pkt_type_ok(pkt_type)))
3345 return -EINVAL;
3346
3347 skb->pkt_type = pkt_type;
3348 return 0;
3349 }
3350
3351 static const struct bpf_func_proto bpf_skb_change_type_proto = {
3352 .func = bpf_skb_change_type,
3353 .gpl_only = false,
3354 .ret_type = RET_INTEGER,
3355 .arg1_type = ARG_PTR_TO_CTX,
3356 .arg2_type = ARG_ANYTHING,
3357 };
3358
bpf_skb_net_base_len(const struct sk_buff * skb)3359 static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
3360 {
3361 switch (skb->protocol) {
3362 case htons(ETH_P_IP):
3363 return sizeof(struct iphdr);
3364 case htons(ETH_P_IPV6):
3365 return sizeof(struct ipv6hdr);
3366 default:
3367 return ~0U;
3368 }
3369 }
3370
3371 #define BPF_F_ADJ_ROOM_ENCAP_L3_MASK (BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 | \
3372 BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3373
3374 #define BPF_F_ADJ_ROOM_MASK (BPF_F_ADJ_ROOM_FIXED_GSO | \
3375 BPF_F_ADJ_ROOM_ENCAP_L3_MASK | \
3376 BPF_F_ADJ_ROOM_ENCAP_L4_GRE | \
3377 BPF_F_ADJ_ROOM_ENCAP_L4_UDP | \
3378 BPF_F_ADJ_ROOM_ENCAP_L2_ETH | \
3379 BPF_F_ADJ_ROOM_ENCAP_L2( \
3380 BPF_ADJ_ROOM_ENCAP_L2_MASK))
3381
bpf_skb_net_grow(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3382 static int bpf_skb_net_grow(struct sk_buff *skb, u32 off, u32 len_diff,
3383 u64 flags)
3384 {
3385 u8 inner_mac_len = flags >> BPF_ADJ_ROOM_ENCAP_L2_SHIFT;
3386 bool encap = flags & BPF_F_ADJ_ROOM_ENCAP_L3_MASK;
3387 u16 mac_len = 0, inner_net = 0, inner_trans = 0;
3388 unsigned int gso_type = SKB_GSO_DODGY;
3389 int ret;
3390
3391 if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3392 /* udp gso_size delineates datagrams, only allow if fixed */
3393 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3394 !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3395 return -ENOTSUPP;
3396 }
3397
3398 ret = skb_cow_head(skb, len_diff);
3399 if (unlikely(ret < 0))
3400 return ret;
3401
3402 if (encap) {
3403 if (skb->protocol != htons(ETH_P_IP) &&
3404 skb->protocol != htons(ETH_P_IPV6))
3405 return -ENOTSUPP;
3406
3407 if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4 &&
3408 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3409 return -EINVAL;
3410
3411 if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE &&
3412 flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3413 return -EINVAL;
3414
3415 if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH &&
3416 inner_mac_len < ETH_HLEN)
3417 return -EINVAL;
3418
3419 if (skb->encapsulation)
3420 return -EALREADY;
3421
3422 mac_len = skb->network_header - skb->mac_header;
3423 inner_net = skb->network_header;
3424 if (inner_mac_len > len_diff)
3425 return -EINVAL;
3426 inner_trans = skb->transport_header;
3427 }
3428
3429 ret = bpf_skb_net_hdr_push(skb, off, len_diff);
3430 if (unlikely(ret < 0))
3431 return ret;
3432
3433 if (encap) {
3434 skb->inner_mac_header = inner_net - inner_mac_len;
3435 skb->inner_network_header = inner_net;
3436 skb->inner_transport_header = inner_trans;
3437
3438 if (flags & BPF_F_ADJ_ROOM_ENCAP_L2_ETH)
3439 skb_set_inner_protocol(skb, htons(ETH_P_TEB));
3440 else
3441 skb_set_inner_protocol(skb, skb->protocol);
3442
3443 skb->encapsulation = 1;
3444 skb_set_network_header(skb, mac_len);
3445
3446 if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP)
3447 gso_type |= SKB_GSO_UDP_TUNNEL;
3448 else if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE)
3449 gso_type |= SKB_GSO_GRE;
3450 else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3451 gso_type |= SKB_GSO_IPXIP6;
3452 else if (flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3453 gso_type |= SKB_GSO_IPXIP4;
3454
3455 if (flags & BPF_F_ADJ_ROOM_ENCAP_L4_GRE ||
3456 flags & BPF_F_ADJ_ROOM_ENCAP_L4_UDP) {
3457 int nh_len = flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6 ?
3458 sizeof(struct ipv6hdr) :
3459 sizeof(struct iphdr);
3460
3461 skb_set_transport_header(skb, mac_len + nh_len);
3462 }
3463
3464 /* Match skb->protocol to new outer l3 protocol */
3465 if (skb->protocol == htons(ETH_P_IP) &&
3466 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV6)
3467 skb->protocol = htons(ETH_P_IPV6);
3468 else if (skb->protocol == htons(ETH_P_IPV6) &&
3469 flags & BPF_F_ADJ_ROOM_ENCAP_L3_IPV4)
3470 skb->protocol = htons(ETH_P_IP);
3471 }
3472
3473 if (skb_is_gso(skb)) {
3474 struct skb_shared_info *shinfo = skb_shinfo(skb);
3475
3476 /* Due to header grow, MSS needs to be downgraded. */
3477 if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3478 skb_decrease_gso_size(shinfo, len_diff);
3479
3480 /* Header must be checked, and gso_segs recomputed. */
3481 shinfo->gso_type |= gso_type;
3482 shinfo->gso_segs = 0;
3483 }
3484
3485 return 0;
3486 }
3487
bpf_skb_net_shrink(struct sk_buff * skb,u32 off,u32 len_diff,u64 flags)3488 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 off, u32 len_diff,
3489 u64 flags)
3490 {
3491 int ret;
3492
3493 if (unlikely(flags & ~(BPF_F_ADJ_ROOM_FIXED_GSO |
3494 BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
3495 return -EINVAL;
3496
3497 if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) {
3498 /* udp gso_size delineates datagrams, only allow if fixed */
3499 if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ||
3500 !(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3501 return -ENOTSUPP;
3502 }
3503
3504 ret = skb_unclone(skb, GFP_ATOMIC);
3505 if (unlikely(ret < 0))
3506 return ret;
3507
3508 ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
3509 if (unlikely(ret < 0))
3510 return ret;
3511
3512 if (skb_is_gso(skb)) {
3513 struct skb_shared_info *shinfo = skb_shinfo(skb);
3514
3515 /* Due to header shrink, MSS can be upgraded. */
3516 if (!(flags & BPF_F_ADJ_ROOM_FIXED_GSO))
3517 skb_increase_gso_size(shinfo, len_diff);
3518
3519 /* Header must be checked, and gso_segs recomputed. */
3520 shinfo->gso_type |= SKB_GSO_DODGY;
3521 shinfo->gso_segs = 0;
3522 }
3523
3524 return 0;
3525 }
3526
3527 #define BPF_SKB_MAX_LEN SKB_MAX_ALLOC
3528
BPF_CALL_4(sk_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3529 BPF_CALL_4(sk_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3530 u32, mode, u64, flags)
3531 {
3532 u32 len_diff_abs = abs(len_diff);
3533 bool shrink = len_diff < 0;
3534 int ret = 0;
3535
3536 if (unlikely(flags || mode))
3537 return -EINVAL;
3538 if (unlikely(len_diff_abs > 0xfffU))
3539 return -EFAULT;
3540
3541 if (!shrink) {
3542 ret = skb_cow(skb, len_diff);
3543 if (unlikely(ret < 0))
3544 return ret;
3545 __skb_push(skb, len_diff_abs);
3546 memset(skb->data, 0, len_diff_abs);
3547 } else {
3548 if (unlikely(!pskb_may_pull(skb, len_diff_abs)))
3549 return -ENOMEM;
3550 __skb_pull(skb, len_diff_abs);
3551 }
3552 if (tls_sw_has_ctx_rx(skb->sk)) {
3553 struct strp_msg *rxm = strp_msg(skb);
3554
3555 rxm->full_len += len_diff;
3556 }
3557 return ret;
3558 }
3559
3560 static const struct bpf_func_proto sk_skb_adjust_room_proto = {
3561 .func = sk_skb_adjust_room,
3562 .gpl_only = false,
3563 .ret_type = RET_INTEGER,
3564 .arg1_type = ARG_PTR_TO_CTX,
3565 .arg2_type = ARG_ANYTHING,
3566 .arg3_type = ARG_ANYTHING,
3567 .arg4_type = ARG_ANYTHING,
3568 };
3569
BPF_CALL_4(bpf_skb_adjust_room,struct sk_buff *,skb,s32,len_diff,u32,mode,u64,flags)3570 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
3571 u32, mode, u64, flags)
3572 {
3573 u32 len_cur, len_diff_abs = abs(len_diff);
3574 u32 len_min = bpf_skb_net_base_len(skb);
3575 u32 len_max = BPF_SKB_MAX_LEN;
3576 __be16 proto = skb->protocol;
3577 bool shrink = len_diff < 0;
3578 u32 off;
3579 int ret;
3580
3581 if (unlikely(flags & ~(BPF_F_ADJ_ROOM_MASK |
3582 BPF_F_ADJ_ROOM_NO_CSUM_RESET)))
3583 return -EINVAL;
3584 if (unlikely(len_diff_abs > 0xfffU))
3585 return -EFAULT;
3586 if (unlikely(proto != htons(ETH_P_IP) &&
3587 proto != htons(ETH_P_IPV6)))
3588 return -ENOTSUPP;
3589
3590 off = skb_mac_header_len(skb);
3591 switch (mode) {
3592 case BPF_ADJ_ROOM_NET:
3593 off += bpf_skb_net_base_len(skb);
3594 break;
3595 case BPF_ADJ_ROOM_MAC:
3596 break;
3597 default:
3598 return -ENOTSUPP;
3599 }
3600
3601 len_cur = skb->len - skb_network_offset(skb);
3602 if ((shrink && (len_diff_abs >= len_cur ||
3603 len_cur - len_diff_abs < len_min)) ||
3604 (!shrink && (skb->len + len_diff_abs > len_max &&
3605 !skb_is_gso(skb))))
3606 return -ENOTSUPP;
3607
3608 ret = shrink ? bpf_skb_net_shrink(skb, off, len_diff_abs, flags) :
3609 bpf_skb_net_grow(skb, off, len_diff_abs, flags);
3610 if (!ret && !(flags & BPF_F_ADJ_ROOM_NO_CSUM_RESET))
3611 __skb_reset_checksum_unnecessary(skb);
3612
3613 bpf_compute_data_pointers(skb);
3614 return ret;
3615 }
3616
3617 static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
3618 .func = bpf_skb_adjust_room,
3619 .gpl_only = false,
3620 .ret_type = RET_INTEGER,
3621 .arg1_type = ARG_PTR_TO_CTX,
3622 .arg2_type = ARG_ANYTHING,
3623 .arg3_type = ARG_ANYTHING,
3624 .arg4_type = ARG_ANYTHING,
3625 };
3626
__bpf_skb_min_len(const struct sk_buff * skb)3627 static u32 __bpf_skb_min_len(const struct sk_buff *skb)
3628 {
3629 u32 min_len = skb_network_offset(skb);
3630
3631 if (skb_transport_header_was_set(skb))
3632 min_len = skb_transport_offset(skb);
3633 if (skb->ip_summed == CHECKSUM_PARTIAL)
3634 min_len = skb_checksum_start_offset(skb) +
3635 skb->csum_offset + sizeof(__sum16);
3636 return min_len;
3637 }
3638
bpf_skb_grow_rcsum(struct sk_buff * skb,unsigned int new_len)3639 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
3640 {
3641 unsigned int old_len = skb->len;
3642 int ret;
3643
3644 ret = __skb_grow_rcsum(skb, new_len);
3645 if (!ret)
3646 memset(skb->data + old_len, 0, new_len - old_len);
3647 return ret;
3648 }
3649
bpf_skb_trim_rcsum(struct sk_buff * skb,unsigned int new_len)3650 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
3651 {
3652 return __skb_trim_rcsum(skb, new_len);
3653 }
3654
__bpf_skb_change_tail(struct sk_buff * skb,u32 new_len,u64 flags)3655 static inline int __bpf_skb_change_tail(struct sk_buff *skb, u32 new_len,
3656 u64 flags)
3657 {
3658 u32 max_len = BPF_SKB_MAX_LEN;
3659 u32 min_len = __bpf_skb_min_len(skb);
3660 int ret;
3661
3662 if (unlikely(flags || new_len > max_len || new_len < min_len))
3663 return -EINVAL;
3664 if (skb->encapsulation)
3665 return -ENOTSUPP;
3666
3667 /* The basic idea of this helper is that it's performing the
3668 * needed work to either grow or trim an skb, and eBPF program
3669 * rewrites the rest via helpers like bpf_skb_store_bytes(),
3670 * bpf_lX_csum_replace() and others rather than passing a raw
3671 * buffer here. This one is a slow path helper and intended
3672 * for replies with control messages.
3673 *
3674 * Like in bpf_skb_change_proto(), we want to keep this rather
3675 * minimal and without protocol specifics so that we are able
3676 * to separate concerns as in bpf_skb_store_bytes() should only
3677 * be the one responsible for writing buffers.
3678 *
3679 * It's really expected to be a slow path operation here for
3680 * control message replies, so we're implicitly linearizing,
3681 * uncloning and drop offloads from the skb by this.
3682 */
3683 ret = __bpf_try_make_writable(skb, skb->len);
3684 if (!ret) {
3685 if (new_len > skb->len)
3686 ret = bpf_skb_grow_rcsum(skb, new_len);
3687 else if (new_len < skb->len)
3688 ret = bpf_skb_trim_rcsum(skb, new_len);
3689 if (!ret && skb_is_gso(skb))
3690 skb_gso_reset(skb);
3691 }
3692 return ret;
3693 }
3694
BPF_CALL_3(bpf_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3695 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3696 u64, flags)
3697 {
3698 int ret = __bpf_skb_change_tail(skb, new_len, flags);
3699
3700 bpf_compute_data_pointers(skb);
3701 return ret;
3702 }
3703
3704 static const struct bpf_func_proto bpf_skb_change_tail_proto = {
3705 .func = bpf_skb_change_tail,
3706 .gpl_only = false,
3707 .ret_type = RET_INTEGER,
3708 .arg1_type = ARG_PTR_TO_CTX,
3709 .arg2_type = ARG_ANYTHING,
3710 .arg3_type = ARG_ANYTHING,
3711 };
3712
BPF_CALL_3(sk_skb_change_tail,struct sk_buff *,skb,u32,new_len,u64,flags)3713 BPF_CALL_3(sk_skb_change_tail, struct sk_buff *, skb, u32, new_len,
3714 u64, flags)
3715 {
3716 return __bpf_skb_change_tail(skb, new_len, flags);
3717 }
3718
3719 static const struct bpf_func_proto sk_skb_change_tail_proto = {
3720 .func = sk_skb_change_tail,
3721 .gpl_only = false,
3722 .ret_type = RET_INTEGER,
3723 .arg1_type = ARG_PTR_TO_CTX,
3724 .arg2_type = ARG_ANYTHING,
3725 .arg3_type = ARG_ANYTHING,
3726 };
3727
__bpf_skb_change_head(struct sk_buff * skb,u32 head_room,u64 flags)3728 static inline int __bpf_skb_change_head(struct sk_buff *skb, u32 head_room,
3729 u64 flags)
3730 {
3731 u32 max_len = BPF_SKB_MAX_LEN;
3732 u32 new_len = skb->len + head_room;
3733 int ret;
3734
3735 if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
3736 new_len < skb->len))
3737 return -EINVAL;
3738
3739 ret = skb_cow(skb, head_room);
3740 if (likely(!ret)) {
3741 /* Idea for this helper is that we currently only
3742 * allow to expand on mac header. This means that
3743 * skb->protocol network header, etc, stay as is.
3744 * Compared to bpf_skb_change_tail(), we're more
3745 * flexible due to not needing to linearize or
3746 * reset GSO. Intention for this helper is to be
3747 * used by an L3 skb that needs to push mac header
3748 * for redirection into L2 device.
3749 */
3750 __skb_push(skb, head_room);
3751 memset(skb->data, 0, head_room);
3752 skb_reset_mac_header(skb);
3753 skb_reset_mac_len(skb);
3754 }
3755
3756 return ret;
3757 }
3758
BPF_CALL_3(bpf_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3759 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
3760 u64, flags)
3761 {
3762 int ret = __bpf_skb_change_head(skb, head_room, flags);
3763
3764 bpf_compute_data_pointers(skb);
3765 return ret;
3766 }
3767
3768 static const struct bpf_func_proto bpf_skb_change_head_proto = {
3769 .func = bpf_skb_change_head,
3770 .gpl_only = false,
3771 .ret_type = RET_INTEGER,
3772 .arg1_type = ARG_PTR_TO_CTX,
3773 .arg2_type = ARG_ANYTHING,
3774 .arg3_type = ARG_ANYTHING,
3775 };
3776
BPF_CALL_3(sk_skb_change_head,struct sk_buff *,skb,u32,head_room,u64,flags)3777 BPF_CALL_3(sk_skb_change_head, struct sk_buff *, skb, u32, head_room,
3778 u64, flags)
3779 {
3780 return __bpf_skb_change_head(skb, head_room, flags);
3781 }
3782
3783 static const struct bpf_func_proto sk_skb_change_head_proto = {
3784 .func = sk_skb_change_head,
3785 .gpl_only = false,
3786 .ret_type = RET_INTEGER,
3787 .arg1_type = ARG_PTR_TO_CTX,
3788 .arg2_type = ARG_ANYTHING,
3789 .arg3_type = ARG_ANYTHING,
3790 };
3791
BPF_CALL_1(bpf_xdp_get_buff_len,struct xdp_buff *,xdp)3792 BPF_CALL_1(bpf_xdp_get_buff_len, struct xdp_buff*, xdp)
3793 {
3794 return xdp_get_buff_len(xdp);
3795 }
3796
3797 static const struct bpf_func_proto bpf_xdp_get_buff_len_proto = {
3798 .func = bpf_xdp_get_buff_len,
3799 .gpl_only = false,
3800 .ret_type = RET_INTEGER,
3801 .arg1_type = ARG_PTR_TO_CTX,
3802 };
3803
3804 BTF_ID_LIST_SINGLE(bpf_xdp_get_buff_len_bpf_ids, struct, xdp_buff)
3805
3806 const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto = {
3807 .func = bpf_xdp_get_buff_len,
3808 .gpl_only = false,
3809 .arg1_type = ARG_PTR_TO_BTF_ID,
3810 .arg1_btf_id = &bpf_xdp_get_buff_len_bpf_ids[0],
3811 };
3812
xdp_get_metalen(const struct xdp_buff * xdp)3813 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
3814 {
3815 return xdp_data_meta_unsupported(xdp) ? 0 :
3816 xdp->data - xdp->data_meta;
3817 }
3818
BPF_CALL_2(bpf_xdp_adjust_head,struct xdp_buff *,xdp,int,offset)3819 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
3820 {
3821 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
3822 unsigned long metalen = xdp_get_metalen(xdp);
3823 void *data_start = xdp_frame_end + metalen;
3824 void *data = xdp->data + offset;
3825
3826 if (unlikely(data < data_start ||
3827 data > xdp->data_end - ETH_HLEN))
3828 return -EINVAL;
3829
3830 if (metalen)
3831 memmove(xdp->data_meta + offset,
3832 xdp->data_meta, metalen);
3833 xdp->data_meta += offset;
3834 xdp->data = data;
3835
3836 return 0;
3837 }
3838
3839 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
3840 .func = bpf_xdp_adjust_head,
3841 .gpl_only = false,
3842 .ret_type = RET_INTEGER,
3843 .arg1_type = ARG_PTR_TO_CTX,
3844 .arg2_type = ARG_ANYTHING,
3845 };
3846
bpf_xdp_copy_buf(struct xdp_buff * xdp,unsigned long off,void * buf,unsigned long len,bool flush)3847 static void bpf_xdp_copy_buf(struct xdp_buff *xdp, unsigned long off,
3848 void *buf, unsigned long len, bool flush)
3849 {
3850 unsigned long ptr_len, ptr_off = 0;
3851 skb_frag_t *next_frag, *end_frag;
3852 struct skb_shared_info *sinfo;
3853 void *src, *dst;
3854 u8 *ptr_buf;
3855
3856 if (likely(xdp->data_end - xdp->data >= off + len)) {
3857 src = flush ? buf : xdp->data + off;
3858 dst = flush ? xdp->data + off : buf;
3859 memcpy(dst, src, len);
3860 return;
3861 }
3862
3863 sinfo = xdp_get_shared_info_from_buff(xdp);
3864 end_frag = &sinfo->frags[sinfo->nr_frags];
3865 next_frag = &sinfo->frags[0];
3866
3867 ptr_len = xdp->data_end - xdp->data;
3868 ptr_buf = xdp->data;
3869
3870 while (true) {
3871 if (off < ptr_off + ptr_len) {
3872 unsigned long copy_off = off - ptr_off;
3873 unsigned long copy_len = min(len, ptr_len - copy_off);
3874
3875 src = flush ? buf : ptr_buf + copy_off;
3876 dst = flush ? ptr_buf + copy_off : buf;
3877 memcpy(dst, src, copy_len);
3878
3879 off += copy_len;
3880 len -= copy_len;
3881 buf += copy_len;
3882 }
3883
3884 if (!len || next_frag == end_frag)
3885 break;
3886
3887 ptr_off += ptr_len;
3888 ptr_buf = skb_frag_address(next_frag);
3889 ptr_len = skb_frag_size(next_frag);
3890 next_frag++;
3891 }
3892 }
3893
bpf_xdp_pointer(struct xdp_buff * xdp,u32 offset,u32 len)3894 static void *bpf_xdp_pointer(struct xdp_buff *xdp, u32 offset, u32 len)
3895 {
3896 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
3897 u32 size = xdp->data_end - xdp->data;
3898 void *addr = xdp->data;
3899 int i;
3900
3901 if (unlikely(offset > 0xffff || len > 0xffff))
3902 return ERR_PTR(-EFAULT);
3903
3904 if (offset + len > xdp_get_buff_len(xdp))
3905 return ERR_PTR(-EINVAL);
3906
3907 if (offset < size) /* linear area */
3908 goto out;
3909
3910 offset -= size;
3911 for (i = 0; i < sinfo->nr_frags; i++) { /* paged area */
3912 u32 frag_size = skb_frag_size(&sinfo->frags[i]);
3913
3914 if (offset < frag_size) {
3915 addr = skb_frag_address(&sinfo->frags[i]);
3916 size = frag_size;
3917 break;
3918 }
3919 offset -= frag_size;
3920 }
3921 out:
3922 return offset + len <= size ? addr + offset : NULL;
3923 }
3924
BPF_CALL_4(bpf_xdp_load_bytes,struct xdp_buff *,xdp,u32,offset,void *,buf,u32,len)3925 BPF_CALL_4(bpf_xdp_load_bytes, struct xdp_buff *, xdp, u32, offset,
3926 void *, buf, u32, len)
3927 {
3928 void *ptr;
3929
3930 ptr = bpf_xdp_pointer(xdp, offset, len);
3931 if (IS_ERR(ptr))
3932 return PTR_ERR(ptr);
3933
3934 if (!ptr)
3935 bpf_xdp_copy_buf(xdp, offset, buf, len, false);
3936 else
3937 memcpy(buf, ptr, len);
3938
3939 return 0;
3940 }
3941
3942 static const struct bpf_func_proto bpf_xdp_load_bytes_proto = {
3943 .func = bpf_xdp_load_bytes,
3944 .gpl_only = false,
3945 .ret_type = RET_INTEGER,
3946 .arg1_type = ARG_PTR_TO_CTX,
3947 .arg2_type = ARG_ANYTHING,
3948 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
3949 .arg4_type = ARG_CONST_SIZE,
3950 };
3951
BPF_CALL_4(bpf_xdp_store_bytes,struct xdp_buff *,xdp,u32,offset,void *,buf,u32,len)3952 BPF_CALL_4(bpf_xdp_store_bytes, struct xdp_buff *, xdp, u32, offset,
3953 void *, buf, u32, len)
3954 {
3955 void *ptr;
3956
3957 ptr = bpf_xdp_pointer(xdp, offset, len);
3958 if (IS_ERR(ptr))
3959 return PTR_ERR(ptr);
3960
3961 if (!ptr)
3962 bpf_xdp_copy_buf(xdp, offset, buf, len, true);
3963 else
3964 memcpy(ptr, buf, len);
3965
3966 return 0;
3967 }
3968
3969 static const struct bpf_func_proto bpf_xdp_store_bytes_proto = {
3970 .func = bpf_xdp_store_bytes,
3971 .gpl_only = false,
3972 .ret_type = RET_INTEGER,
3973 .arg1_type = ARG_PTR_TO_CTX,
3974 .arg2_type = ARG_ANYTHING,
3975 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
3976 .arg4_type = ARG_CONST_SIZE,
3977 };
3978
bpf_xdp_frags_increase_tail(struct xdp_buff * xdp,int offset)3979 static int bpf_xdp_frags_increase_tail(struct xdp_buff *xdp, int offset)
3980 {
3981 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
3982 skb_frag_t *frag = &sinfo->frags[sinfo->nr_frags - 1];
3983 struct xdp_rxq_info *rxq = xdp->rxq;
3984 unsigned int tailroom;
3985
3986 if (!rxq->frag_size || rxq->frag_size > xdp->frame_sz)
3987 return -EOPNOTSUPP;
3988
3989 tailroom = rxq->frag_size - skb_frag_size(frag) - skb_frag_off(frag);
3990 if (unlikely(offset > tailroom))
3991 return -EINVAL;
3992
3993 memset(skb_frag_address(frag) + skb_frag_size(frag), 0, offset);
3994 skb_frag_size_add(frag, offset);
3995 sinfo->xdp_frags_size += offset;
3996
3997 return 0;
3998 }
3999
bpf_xdp_frags_shrink_tail(struct xdp_buff * xdp,int offset)4000 static int bpf_xdp_frags_shrink_tail(struct xdp_buff *xdp, int offset)
4001 {
4002 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
4003 int i, n_frags_free = 0, len_free = 0;
4004
4005 if (unlikely(offset > (int)xdp_get_buff_len(xdp) - ETH_HLEN))
4006 return -EINVAL;
4007
4008 for (i = sinfo->nr_frags - 1; i >= 0 && offset > 0; i--) {
4009 skb_frag_t *frag = &sinfo->frags[i];
4010 int shrink = min_t(int, offset, skb_frag_size(frag));
4011
4012 len_free += shrink;
4013 offset -= shrink;
4014
4015 if (skb_frag_size(frag) == shrink) {
4016 struct page *page = skb_frag_page(frag);
4017
4018 __xdp_return(page_address(page), &xdp->rxq->mem,
4019 false, NULL);
4020 n_frags_free++;
4021 } else {
4022 skb_frag_size_sub(frag, shrink);
4023 break;
4024 }
4025 }
4026 sinfo->nr_frags -= n_frags_free;
4027 sinfo->xdp_frags_size -= len_free;
4028
4029 if (unlikely(!sinfo->nr_frags)) {
4030 xdp_buff_clear_frags_flag(xdp);
4031 xdp->data_end -= offset;
4032 }
4033
4034 return 0;
4035 }
4036
BPF_CALL_2(bpf_xdp_adjust_tail,struct xdp_buff *,xdp,int,offset)4037 BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset)
4038 {
4039 void *data_hard_end = xdp_data_hard_end(xdp); /* use xdp->frame_sz */
4040 void *data_end = xdp->data_end + offset;
4041
4042 if (unlikely(xdp_buff_has_frags(xdp))) { /* non-linear xdp buff */
4043 if (offset < 0)
4044 return bpf_xdp_frags_shrink_tail(xdp, -offset);
4045
4046 return bpf_xdp_frags_increase_tail(xdp, offset);
4047 }
4048
4049 /* Notice that xdp_data_hard_end have reserved some tailroom */
4050 if (unlikely(data_end > data_hard_end))
4051 return -EINVAL;
4052
4053 /* ALL drivers MUST init xdp->frame_sz, chicken check below */
4054 if (unlikely(xdp->frame_sz > PAGE_SIZE)) {
4055 WARN_ONCE(1, "Too BIG xdp->frame_sz = %d\n", xdp->frame_sz);
4056 return -EINVAL;
4057 }
4058
4059 if (unlikely(data_end < xdp->data + ETH_HLEN))
4060 return -EINVAL;
4061
4062 /* Clear memory area on grow, can contain uninit kernel memory */
4063 if (offset > 0)
4064 memset(xdp->data_end, 0, offset);
4065
4066 xdp->data_end = data_end;
4067
4068 return 0;
4069 }
4070
4071 static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = {
4072 .func = bpf_xdp_adjust_tail,
4073 .gpl_only = false,
4074 .ret_type = RET_INTEGER,
4075 .arg1_type = ARG_PTR_TO_CTX,
4076 .arg2_type = ARG_ANYTHING,
4077 };
4078
BPF_CALL_2(bpf_xdp_adjust_meta,struct xdp_buff *,xdp,int,offset)4079 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
4080 {
4081 void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame);
4082 void *meta = xdp->data_meta + offset;
4083 unsigned long metalen = xdp->data - meta;
4084
4085 if (xdp_data_meta_unsupported(xdp))
4086 return -ENOTSUPP;
4087 if (unlikely(meta < xdp_frame_end ||
4088 meta > xdp->data))
4089 return -EINVAL;
4090 if (unlikely(xdp_metalen_invalid(metalen)))
4091 return -EACCES;
4092
4093 xdp->data_meta = meta;
4094
4095 return 0;
4096 }
4097
4098 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
4099 .func = bpf_xdp_adjust_meta,
4100 .gpl_only = false,
4101 .ret_type = RET_INTEGER,
4102 .arg1_type = ARG_PTR_TO_CTX,
4103 .arg2_type = ARG_ANYTHING,
4104 };
4105
4106 /* XDP_REDIRECT works by a three-step process, implemented in the functions
4107 * below:
4108 *
4109 * 1. The bpf_redirect() and bpf_redirect_map() helpers will lookup the target
4110 * of the redirect and store it (along with some other metadata) in a per-CPU
4111 * struct bpf_redirect_info.
4112 *
4113 * 2. When the program returns the XDP_REDIRECT return code, the driver will
4114 * call xdp_do_redirect() which will use the information in struct
4115 * bpf_redirect_info to actually enqueue the frame into a map type-specific
4116 * bulk queue structure.
4117 *
4118 * 3. Before exiting its NAPI poll loop, the driver will call xdp_do_flush(),
4119 * which will flush all the different bulk queues, thus completing the
4120 * redirect.
4121 *
4122 * Pointers to the map entries will be kept around for this whole sequence of
4123 * steps, protected by RCU. However, there is no top-level rcu_read_lock() in
4124 * the core code; instead, the RCU protection relies on everything happening
4125 * inside a single NAPI poll sequence, which means it's between a pair of calls
4126 * to local_bh_disable()/local_bh_enable().
4127 *
4128 * The map entries are marked as __rcu and the map code makes sure to
4129 * dereference those pointers with rcu_dereference_check() in a way that works
4130 * for both sections that to hold an rcu_read_lock() and sections that are
4131 * called from NAPI without a separate rcu_read_lock(). The code below does not
4132 * use RCU annotations, but relies on those in the map code.
4133 */
xdp_do_flush(void)4134 void xdp_do_flush(void)
4135 {
4136 __dev_flush();
4137 __cpu_map_flush();
4138 __xsk_map_flush();
4139 }
4140 EXPORT_SYMBOL_GPL(xdp_do_flush);
4141
bpf_clear_redirect_map(struct bpf_map * map)4142 void bpf_clear_redirect_map(struct bpf_map *map)
4143 {
4144 struct bpf_redirect_info *ri;
4145 int cpu;
4146
4147 for_each_possible_cpu(cpu) {
4148 ri = per_cpu_ptr(&bpf_redirect_info, cpu);
4149 /* Avoid polluting remote cacheline due to writes if
4150 * not needed. Once we pass this test, we need the
4151 * cmpxchg() to make sure it hasn't been changed in
4152 * the meantime by remote CPU.
4153 */
4154 if (unlikely(READ_ONCE(ri->map) == map))
4155 cmpxchg(&ri->map, map, NULL);
4156 }
4157 }
4158
4159 DEFINE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key);
4160 EXPORT_SYMBOL_GPL(bpf_master_redirect_enabled_key);
4161
xdp_master_redirect(struct xdp_buff * xdp)4162 u32 xdp_master_redirect(struct xdp_buff *xdp)
4163 {
4164 struct net_device *master, *slave;
4165 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4166
4167 master = netdev_master_upper_dev_get_rcu(xdp->rxq->dev);
4168 slave = master->netdev_ops->ndo_xdp_get_xmit_slave(master, xdp);
4169 if (slave && slave != xdp->rxq->dev) {
4170 /* The target device is different from the receiving device, so
4171 * redirect it to the new device.
4172 * Using XDP_REDIRECT gets the correct behaviour from XDP enabled
4173 * drivers to unmap the packet from their rx ring.
4174 */
4175 ri->tgt_index = slave->ifindex;
4176 ri->map_id = INT_MAX;
4177 ri->map_type = BPF_MAP_TYPE_UNSPEC;
4178 return XDP_REDIRECT;
4179 }
4180 return XDP_TX;
4181 }
4182 EXPORT_SYMBOL_GPL(xdp_master_redirect);
4183
__xdp_do_redirect_xsk(struct bpf_redirect_info * ri,struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4184 static inline int __xdp_do_redirect_xsk(struct bpf_redirect_info *ri,
4185 struct net_device *dev,
4186 struct xdp_buff *xdp,
4187 struct bpf_prog *xdp_prog)
4188 {
4189 enum bpf_map_type map_type = ri->map_type;
4190 void *fwd = ri->tgt_value;
4191 u32 map_id = ri->map_id;
4192 int err;
4193
4194 ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4195 ri->map_type = BPF_MAP_TYPE_UNSPEC;
4196
4197 err = __xsk_map_redirect(fwd, xdp);
4198 if (unlikely(err))
4199 goto err;
4200
4201 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4202 return 0;
4203 err:
4204 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4205 return err;
4206 }
4207
__xdp_do_redirect_frame(struct bpf_redirect_info * ri,struct net_device * dev,struct xdp_frame * xdpf,struct bpf_prog * xdp_prog)4208 static __always_inline int __xdp_do_redirect_frame(struct bpf_redirect_info *ri,
4209 struct net_device *dev,
4210 struct xdp_frame *xdpf,
4211 struct bpf_prog *xdp_prog)
4212 {
4213 enum bpf_map_type map_type = ri->map_type;
4214 void *fwd = ri->tgt_value;
4215 u32 map_id = ri->map_id;
4216 struct bpf_map *map;
4217 int err;
4218
4219 ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4220 ri->map_type = BPF_MAP_TYPE_UNSPEC;
4221
4222 if (unlikely(!xdpf)) {
4223 err = -EOVERFLOW;
4224 goto err;
4225 }
4226
4227 switch (map_type) {
4228 case BPF_MAP_TYPE_DEVMAP:
4229 fallthrough;
4230 case BPF_MAP_TYPE_DEVMAP_HASH:
4231 map = READ_ONCE(ri->map);
4232 if (unlikely(map)) {
4233 WRITE_ONCE(ri->map, NULL);
4234 err = dev_map_enqueue_multi(xdpf, dev, map,
4235 ri->flags & BPF_F_EXCLUDE_INGRESS);
4236 } else {
4237 err = dev_map_enqueue(fwd, xdpf, dev);
4238 }
4239 break;
4240 case BPF_MAP_TYPE_CPUMAP:
4241 err = cpu_map_enqueue(fwd, xdpf, dev);
4242 break;
4243 case BPF_MAP_TYPE_UNSPEC:
4244 if (map_id == INT_MAX) {
4245 fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
4246 if (unlikely(!fwd)) {
4247 err = -EINVAL;
4248 break;
4249 }
4250 err = dev_xdp_enqueue(fwd, xdpf, dev);
4251 break;
4252 }
4253 fallthrough;
4254 default:
4255 err = -EBADRQC;
4256 }
4257
4258 if (unlikely(err))
4259 goto err;
4260
4261 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4262 return 0;
4263 err:
4264 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4265 return err;
4266 }
4267
xdp_do_redirect(struct net_device * dev,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4268 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
4269 struct bpf_prog *xdp_prog)
4270 {
4271 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4272 enum bpf_map_type map_type = ri->map_type;
4273
4274 /* XDP_REDIRECT is not fully supported yet for xdp frags since
4275 * not all XDP capable drivers can map non-linear xdp_frame in
4276 * ndo_xdp_xmit.
4277 */
4278 if (unlikely(xdp_buff_has_frags(xdp) &&
4279 map_type != BPF_MAP_TYPE_CPUMAP))
4280 return -EOPNOTSUPP;
4281
4282 if (map_type == BPF_MAP_TYPE_XSKMAP)
4283 return __xdp_do_redirect_xsk(ri, dev, xdp, xdp_prog);
4284
4285 return __xdp_do_redirect_frame(ri, dev, xdp_convert_buff_to_frame(xdp),
4286 xdp_prog);
4287 }
4288 EXPORT_SYMBOL_GPL(xdp_do_redirect);
4289
xdp_do_redirect_frame(struct net_device * dev,struct xdp_buff * xdp,struct xdp_frame * xdpf,struct bpf_prog * xdp_prog)4290 int xdp_do_redirect_frame(struct net_device *dev, struct xdp_buff *xdp,
4291 struct xdp_frame *xdpf, struct bpf_prog *xdp_prog)
4292 {
4293 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4294 enum bpf_map_type map_type = ri->map_type;
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, xdpf, xdp_prog);
4300 }
4301 EXPORT_SYMBOL_GPL(xdp_do_redirect_frame);
4302
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)4303 static int xdp_do_generic_redirect_map(struct net_device *dev,
4304 struct sk_buff *skb,
4305 struct xdp_buff *xdp,
4306 struct bpf_prog *xdp_prog,
4307 void *fwd,
4308 enum bpf_map_type map_type, u32 map_id)
4309 {
4310 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4311 struct bpf_map *map;
4312 int err;
4313
4314 switch (map_type) {
4315 case BPF_MAP_TYPE_DEVMAP:
4316 fallthrough;
4317 case BPF_MAP_TYPE_DEVMAP_HASH:
4318 map = READ_ONCE(ri->map);
4319 if (unlikely(map)) {
4320 WRITE_ONCE(ri->map, NULL);
4321 err = dev_map_redirect_multi(dev, skb, xdp_prog, map,
4322 ri->flags & BPF_F_EXCLUDE_INGRESS);
4323 } else {
4324 err = dev_map_generic_redirect(fwd, skb, xdp_prog);
4325 }
4326 if (unlikely(err))
4327 goto err;
4328 break;
4329 case BPF_MAP_TYPE_XSKMAP:
4330 err = xsk_generic_rcv(fwd, xdp);
4331 if (err)
4332 goto err;
4333 consume_skb(skb);
4334 break;
4335 case BPF_MAP_TYPE_CPUMAP:
4336 err = cpu_map_generic_redirect(fwd, skb);
4337 if (unlikely(err))
4338 goto err;
4339 break;
4340 default:
4341 err = -EBADRQC;
4342 goto err;
4343 }
4344
4345 _trace_xdp_redirect_map(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index);
4346 return 0;
4347 err:
4348 _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map_type, map_id, ri->tgt_index, err);
4349 return err;
4350 }
4351
xdp_do_generic_redirect(struct net_device * dev,struct sk_buff * skb,struct xdp_buff * xdp,struct bpf_prog * xdp_prog)4352 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
4353 struct xdp_buff *xdp, struct bpf_prog *xdp_prog)
4354 {
4355 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4356 enum bpf_map_type map_type = ri->map_type;
4357 void *fwd = ri->tgt_value;
4358 u32 map_id = ri->map_id;
4359 int err;
4360
4361 ri->map_id = 0; /* Valid map id idr range: [1,INT_MAX[ */
4362 ri->map_type = BPF_MAP_TYPE_UNSPEC;
4363
4364 if (map_type == BPF_MAP_TYPE_UNSPEC && map_id == INT_MAX) {
4365 fwd = dev_get_by_index_rcu(dev_net(dev), ri->tgt_index);
4366 if (unlikely(!fwd)) {
4367 err = -EINVAL;
4368 goto err;
4369 }
4370
4371 err = xdp_ok_fwd_dev(fwd, skb->len);
4372 if (unlikely(err))
4373 goto err;
4374
4375 skb->dev = fwd;
4376 _trace_xdp_redirect(dev, xdp_prog, ri->tgt_index);
4377 generic_xdp_tx(skb, xdp_prog);
4378 return 0;
4379 }
4380
4381 return xdp_do_generic_redirect_map(dev, skb, xdp, xdp_prog, fwd, map_type, map_id);
4382 err:
4383 _trace_xdp_redirect_err(dev, xdp_prog, ri->tgt_index, err);
4384 return err;
4385 }
4386
BPF_CALL_2(bpf_xdp_redirect,u32,ifindex,u64,flags)4387 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
4388 {
4389 struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info);
4390
4391 if (unlikely(flags))
4392 return XDP_ABORTED;
4393
4394 /* NB! Map type UNSPEC and map_id == INT_MAX (never generated
4395 * by map_idr) is used for ifindex based XDP redirect.
4396 */
4397 ri->tgt_index = ifindex;
4398 ri->map_id = INT_MAX;
4399 ri->map_type = BPF_MAP_TYPE_UNSPEC;
4400
4401 return XDP_REDIRECT;
4402 }
4403
4404 static const struct bpf_func_proto bpf_xdp_redirect_proto = {
4405 .func = bpf_xdp_redirect,
4406 .gpl_only = false,
4407 .ret_type = RET_INTEGER,
4408 .arg1_type = ARG_ANYTHING,
4409 .arg2_type = ARG_ANYTHING,
4410 };
4411
BPF_CALL_3(bpf_xdp_redirect_map,struct bpf_map *,map,u32,ifindex,u64,flags)4412 BPF_CALL_3(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex,
4413 u64, flags)
4414 {
4415 return map->ops->map_redirect(map, ifindex, flags);
4416 }
4417
4418 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
4419 .func = bpf_xdp_redirect_map,
4420 .gpl_only = false,
4421 .ret_type = RET_INTEGER,
4422 .arg1_type = ARG_CONST_MAP_PTR,
4423 .arg2_type = ARG_ANYTHING,
4424 .arg3_type = ARG_ANYTHING,
4425 };
4426
bpf_skb_copy(void * dst_buff,const void * skb,unsigned long off,unsigned long len)4427 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
4428 unsigned long off, unsigned long len)
4429 {
4430 void *ptr = skb_header_pointer(skb, off, len, dst_buff);
4431
4432 if (unlikely(!ptr))
4433 return len;
4434 if (ptr != dst_buff)
4435 memcpy(dst_buff, ptr, len);
4436
4437 return 0;
4438 }
4439
BPF_CALL_5(bpf_skb_event_output,struct sk_buff *,skb,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)4440 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
4441 u64, flags, void *, meta, u64, meta_size)
4442 {
4443 u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
4444
4445 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
4446 return -EINVAL;
4447 if (unlikely(!skb || skb_size > skb->len))
4448 return -EFAULT;
4449
4450 return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
4451 bpf_skb_copy);
4452 }
4453
4454 static const struct bpf_func_proto bpf_skb_event_output_proto = {
4455 .func = bpf_skb_event_output,
4456 .gpl_only = true,
4457 .ret_type = RET_INTEGER,
4458 .arg1_type = ARG_PTR_TO_CTX,
4459 .arg2_type = ARG_CONST_MAP_PTR,
4460 .arg3_type = ARG_ANYTHING,
4461 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
4462 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
4463 };
4464
4465 BTF_ID_LIST_SINGLE(bpf_skb_output_btf_ids, struct, sk_buff)
4466
4467 const struct bpf_func_proto bpf_skb_output_proto = {
4468 .func = bpf_skb_event_output,
4469 .gpl_only = true,
4470 .ret_type = RET_INTEGER,
4471 .arg1_type = ARG_PTR_TO_BTF_ID,
4472 .arg1_btf_id = &bpf_skb_output_btf_ids[0],
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
bpf_tunnel_key_af(u64 flags)4479 static unsigned short bpf_tunnel_key_af(u64 flags)
4480 {
4481 return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
4482 }
4483
BPF_CALL_4(bpf_skb_get_tunnel_key,struct sk_buff *,skb,struct bpf_tunnel_key *,to,u32,size,u64,flags)4484 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
4485 u32, size, u64, flags)
4486 {
4487 const struct ip_tunnel_info *info = skb_tunnel_info(skb);
4488 u8 compat[sizeof(struct bpf_tunnel_key)];
4489 void *to_orig = to;
4490 int err;
4491
4492 if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) {
4493 err = -EINVAL;
4494 goto err_clear;
4495 }
4496 if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
4497 err = -EPROTO;
4498 goto err_clear;
4499 }
4500 if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
4501 err = -EINVAL;
4502 switch (size) {
4503 case offsetof(struct bpf_tunnel_key, local_ipv6[0]):
4504 case offsetof(struct bpf_tunnel_key, tunnel_label):
4505 case offsetof(struct bpf_tunnel_key, tunnel_ext):
4506 goto set_compat;
4507 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
4508 /* Fixup deprecated structure layouts here, so we have
4509 * a common path later on.
4510 */
4511 if (ip_tunnel_info_af(info) != AF_INET)
4512 goto err_clear;
4513 set_compat:
4514 to = (struct bpf_tunnel_key *)compat;
4515 break;
4516 default:
4517 goto err_clear;
4518 }
4519 }
4520
4521 to->tunnel_id = be64_to_cpu(info->key.tun_id);
4522 to->tunnel_tos = info->key.tos;
4523 to->tunnel_ttl = info->key.ttl;
4524 to->tunnel_ext = 0;
4525
4526 if (flags & BPF_F_TUNINFO_IPV6) {
4527 memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
4528 sizeof(to->remote_ipv6));
4529 memcpy(to->local_ipv6, &info->key.u.ipv6.dst,
4530 sizeof(to->local_ipv6));
4531 to->tunnel_label = be32_to_cpu(info->key.label);
4532 } else {
4533 to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
4534 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
4535 to->local_ipv4 = be32_to_cpu(info->key.u.ipv4.dst);
4536 memset(&to->local_ipv6[1], 0, sizeof(__u32) * 3);
4537 to->tunnel_label = 0;
4538 }
4539
4540 if (unlikely(size != sizeof(struct bpf_tunnel_key)))
4541 memcpy(to_orig, to, size);
4542
4543 return 0;
4544 err_clear:
4545 memset(to_orig, 0, size);
4546 return err;
4547 }
4548
4549 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
4550 .func = bpf_skb_get_tunnel_key,
4551 .gpl_only = false,
4552 .ret_type = RET_INTEGER,
4553 .arg1_type = ARG_PTR_TO_CTX,
4554 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
4555 .arg3_type = ARG_CONST_SIZE,
4556 .arg4_type = ARG_ANYTHING,
4557 };
4558
BPF_CALL_3(bpf_skb_get_tunnel_opt,struct sk_buff *,skb,u8 *,to,u32,size)4559 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
4560 {
4561 const struct ip_tunnel_info *info = skb_tunnel_info(skb);
4562 int err;
4563
4564 if (unlikely(!info ||
4565 !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
4566 err = -ENOENT;
4567 goto err_clear;
4568 }
4569 if (unlikely(size < info->options_len)) {
4570 err = -ENOMEM;
4571 goto err_clear;
4572 }
4573
4574 ip_tunnel_info_opts_get(to, info);
4575 if (size > info->options_len)
4576 memset(to + info->options_len, 0, size - info->options_len);
4577
4578 return info->options_len;
4579 err_clear:
4580 memset(to, 0, size);
4581 return err;
4582 }
4583
4584 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
4585 .func = bpf_skb_get_tunnel_opt,
4586 .gpl_only = false,
4587 .ret_type = RET_INTEGER,
4588 .arg1_type = ARG_PTR_TO_CTX,
4589 .arg2_type = ARG_PTR_TO_UNINIT_MEM,
4590 .arg3_type = ARG_CONST_SIZE,
4591 };
4592
4593 static struct metadata_dst __percpu *md_dst;
4594
BPF_CALL_4(bpf_skb_set_tunnel_key,struct sk_buff *,skb,const struct bpf_tunnel_key *,from,u32,size,u64,flags)4595 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
4596 const struct bpf_tunnel_key *, from, u32, size, u64, flags)
4597 {
4598 struct metadata_dst *md = this_cpu_ptr(md_dst);
4599 u8 compat[sizeof(struct bpf_tunnel_key)];
4600 struct ip_tunnel_info *info;
4601
4602 if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
4603 BPF_F_DONT_FRAGMENT | BPF_F_SEQ_NUMBER)))
4604 return -EINVAL;
4605 if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
4606 switch (size) {
4607 case offsetof(struct bpf_tunnel_key, local_ipv6[0]):
4608 case offsetof(struct bpf_tunnel_key, tunnel_label):
4609 case offsetof(struct bpf_tunnel_key, tunnel_ext):
4610 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
4611 /* Fixup deprecated structure layouts here, so we have
4612 * a common path later on.
4613 */
4614 memcpy(compat, from, size);
4615 memset(compat + size, 0, sizeof(compat) - size);
4616 from = (const struct bpf_tunnel_key *) compat;
4617 break;
4618 default:
4619 return -EINVAL;
4620 }
4621 }
4622 if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
4623 from->tunnel_ext))
4624 return -EINVAL;
4625
4626 skb_dst_drop(skb);
4627 dst_hold((struct dst_entry *) md);
4628 skb_dst_set(skb, (struct dst_entry *) md);
4629
4630 info = &md->u.tun_info;
4631 memset(info, 0, sizeof(*info));
4632 info->mode = IP_TUNNEL_INFO_TX;
4633
4634 info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
4635 if (flags & BPF_F_DONT_FRAGMENT)
4636 info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
4637 if (flags & BPF_F_ZERO_CSUM_TX)
4638 info->key.tun_flags &= ~TUNNEL_CSUM;
4639 if (flags & BPF_F_SEQ_NUMBER)
4640 info->key.tun_flags |= TUNNEL_SEQ;
4641
4642 info->key.tun_id = cpu_to_be64(from->tunnel_id);
4643 info->key.tos = from->tunnel_tos;
4644 info->key.ttl = from->tunnel_ttl;
4645
4646 if (flags & BPF_F_TUNINFO_IPV6) {
4647 info->mode |= IP_TUNNEL_INFO_IPV6;
4648 memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
4649 sizeof(from->remote_ipv6));
4650 memcpy(&info->key.u.ipv6.src, from->local_ipv6,
4651 sizeof(from->local_ipv6));
4652 info->key.label = cpu_to_be32(from->tunnel_label) &
4653 IPV6_FLOWLABEL_MASK;
4654 } else {
4655 info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
4656 info->key.u.ipv4.src = cpu_to_be32(from->local_ipv4);
4657 info->key.flow_flags = FLOWI_FLAG_ANYSRC;
4658 }
4659
4660 return 0;
4661 }
4662
4663 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
4664 .func = bpf_skb_set_tunnel_key,
4665 .gpl_only = false,
4666 .ret_type = RET_INTEGER,
4667 .arg1_type = ARG_PTR_TO_CTX,
4668 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
4669 .arg3_type = ARG_CONST_SIZE,
4670 .arg4_type = ARG_ANYTHING,
4671 };
4672
BPF_CALL_3(bpf_skb_set_tunnel_opt,struct sk_buff *,skb,const u8 *,from,u32,size)4673 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
4674 const u8 *, from, u32, size)
4675 {
4676 struct ip_tunnel_info *info = skb_tunnel_info(skb);
4677 const struct metadata_dst *md = this_cpu_ptr(md_dst);
4678
4679 if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
4680 return -EINVAL;
4681 if (unlikely(size > IP_TUNNEL_OPTS_MAX))
4682 return -ENOMEM;
4683
4684 ip_tunnel_info_opts_set(info, from, size, TUNNEL_OPTIONS_PRESENT);
4685
4686 return 0;
4687 }
4688
4689 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
4690 .func = bpf_skb_set_tunnel_opt,
4691 .gpl_only = false,
4692 .ret_type = RET_INTEGER,
4693 .arg1_type = ARG_PTR_TO_CTX,
4694 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
4695 .arg3_type = ARG_CONST_SIZE,
4696 };
4697
4698 static const struct bpf_func_proto *
bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)4699 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
4700 {
4701 if (!md_dst) {
4702 struct metadata_dst __percpu *tmp;
4703
4704 tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
4705 METADATA_IP_TUNNEL,
4706 GFP_KERNEL);
4707 if (!tmp)
4708 return NULL;
4709 if (cmpxchg(&md_dst, NULL, tmp))
4710 metadata_dst_free_percpu(tmp);
4711 }
4712
4713 switch (which) {
4714 case BPF_FUNC_skb_set_tunnel_key:
4715 return &bpf_skb_set_tunnel_key_proto;
4716 case BPF_FUNC_skb_set_tunnel_opt:
4717 return &bpf_skb_set_tunnel_opt_proto;
4718 default:
4719 return NULL;
4720 }
4721 }
4722
BPF_CALL_3(bpf_skb_under_cgroup,struct sk_buff *,skb,struct bpf_map *,map,u32,idx)4723 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
4724 u32, idx)
4725 {
4726 struct bpf_array *array = container_of(map, struct bpf_array, map);
4727 struct cgroup *cgrp;
4728 struct sock *sk;
4729
4730 sk = skb_to_full_sk(skb);
4731 if (!sk || !sk_fullsock(sk))
4732 return -ENOENT;
4733 if (unlikely(idx >= array->map.max_entries))
4734 return -E2BIG;
4735
4736 cgrp = READ_ONCE(array->ptrs[idx]);
4737 if (unlikely(!cgrp))
4738 return -EAGAIN;
4739
4740 return sk_under_cgroup_hierarchy(sk, cgrp);
4741 }
4742
4743 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
4744 .func = bpf_skb_under_cgroup,
4745 .gpl_only = false,
4746 .ret_type = RET_INTEGER,
4747 .arg1_type = ARG_PTR_TO_CTX,
4748 .arg2_type = ARG_CONST_MAP_PTR,
4749 .arg3_type = ARG_ANYTHING,
4750 };
4751
4752 #ifdef CONFIG_SOCK_CGROUP_DATA
__bpf_sk_cgroup_id(struct sock * sk)4753 static inline u64 __bpf_sk_cgroup_id(struct sock *sk)
4754 {
4755 struct cgroup *cgrp;
4756
4757 sk = sk_to_full_sk(sk);
4758 if (!sk || !sk_fullsock(sk))
4759 return 0;
4760
4761 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4762 return cgroup_id(cgrp);
4763 }
4764
BPF_CALL_1(bpf_skb_cgroup_id,const struct sk_buff *,skb)4765 BPF_CALL_1(bpf_skb_cgroup_id, const struct sk_buff *, skb)
4766 {
4767 return __bpf_sk_cgroup_id(skb->sk);
4768 }
4769
4770 static const struct bpf_func_proto bpf_skb_cgroup_id_proto = {
4771 .func = bpf_skb_cgroup_id,
4772 .gpl_only = false,
4773 .ret_type = RET_INTEGER,
4774 .arg1_type = ARG_PTR_TO_CTX,
4775 };
4776
__bpf_sk_ancestor_cgroup_id(struct sock * sk,int ancestor_level)4777 static inline u64 __bpf_sk_ancestor_cgroup_id(struct sock *sk,
4778 int ancestor_level)
4779 {
4780 struct cgroup *ancestor;
4781 struct cgroup *cgrp;
4782
4783 sk = sk_to_full_sk(sk);
4784 if (!sk || !sk_fullsock(sk))
4785 return 0;
4786
4787 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
4788 ancestor = cgroup_ancestor(cgrp, ancestor_level);
4789 if (!ancestor)
4790 return 0;
4791
4792 return cgroup_id(ancestor);
4793 }
4794
BPF_CALL_2(bpf_skb_ancestor_cgroup_id,const struct sk_buff *,skb,int,ancestor_level)4795 BPF_CALL_2(bpf_skb_ancestor_cgroup_id, const struct sk_buff *, skb, int,
4796 ancestor_level)
4797 {
4798 return __bpf_sk_ancestor_cgroup_id(skb->sk, ancestor_level);
4799 }
4800
4801 static const struct bpf_func_proto bpf_skb_ancestor_cgroup_id_proto = {
4802 .func = bpf_skb_ancestor_cgroup_id,
4803 .gpl_only = false,
4804 .ret_type = RET_INTEGER,
4805 .arg1_type = ARG_PTR_TO_CTX,
4806 .arg2_type = ARG_ANYTHING,
4807 };
4808
BPF_CALL_1(bpf_sk_cgroup_id,struct sock *,sk)4809 BPF_CALL_1(bpf_sk_cgroup_id, struct sock *, sk)
4810 {
4811 return __bpf_sk_cgroup_id(sk);
4812 }
4813
4814 static const struct bpf_func_proto bpf_sk_cgroup_id_proto = {
4815 .func = bpf_sk_cgroup_id,
4816 .gpl_only = false,
4817 .ret_type = RET_INTEGER,
4818 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4819 };
4820
BPF_CALL_2(bpf_sk_ancestor_cgroup_id,struct sock *,sk,int,ancestor_level)4821 BPF_CALL_2(bpf_sk_ancestor_cgroup_id, struct sock *, sk, int, ancestor_level)
4822 {
4823 return __bpf_sk_ancestor_cgroup_id(sk, ancestor_level);
4824 }
4825
4826 static const struct bpf_func_proto bpf_sk_ancestor_cgroup_id_proto = {
4827 .func = bpf_sk_ancestor_cgroup_id,
4828 .gpl_only = false,
4829 .ret_type = RET_INTEGER,
4830 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4831 .arg2_type = ARG_ANYTHING,
4832 };
4833 #endif
4834
bpf_xdp_copy(void * dst,const void * ctx,unsigned long off,unsigned long len)4835 static unsigned long bpf_xdp_copy(void *dst, const void *ctx,
4836 unsigned long off, unsigned long len)
4837 {
4838 struct xdp_buff *xdp = (struct xdp_buff *)ctx;
4839
4840 bpf_xdp_copy_buf(xdp, off, dst, len, false);
4841 return 0;
4842 }
4843
BPF_CALL_5(bpf_xdp_event_output,struct xdp_buff *,xdp,struct bpf_map *,map,u64,flags,void *,meta,u64,meta_size)4844 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
4845 u64, flags, void *, meta, u64, meta_size)
4846 {
4847 u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
4848
4849 if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
4850 return -EINVAL;
4851
4852 if (unlikely(!xdp || xdp_size > xdp_get_buff_len(xdp)))
4853 return -EFAULT;
4854
4855 return bpf_event_output(map, flags, meta, meta_size, xdp,
4856 xdp_size, bpf_xdp_copy);
4857 }
4858
4859 static const struct bpf_func_proto bpf_xdp_event_output_proto = {
4860 .func = bpf_xdp_event_output,
4861 .gpl_only = true,
4862 .ret_type = RET_INTEGER,
4863 .arg1_type = ARG_PTR_TO_CTX,
4864 .arg2_type = ARG_CONST_MAP_PTR,
4865 .arg3_type = ARG_ANYTHING,
4866 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
4867 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
4868 };
4869
4870 BTF_ID_LIST_SINGLE(bpf_xdp_output_btf_ids, struct, xdp_buff)
4871
4872 const struct bpf_func_proto bpf_xdp_output_proto = {
4873 .func = bpf_xdp_event_output,
4874 .gpl_only = true,
4875 .ret_type = RET_INTEGER,
4876 .arg1_type = ARG_PTR_TO_BTF_ID,
4877 .arg1_btf_id = &bpf_xdp_output_btf_ids[0],
4878 .arg2_type = ARG_CONST_MAP_PTR,
4879 .arg3_type = ARG_ANYTHING,
4880 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
4881 .arg5_type = ARG_CONST_SIZE_OR_ZERO,
4882 };
4883
BPF_CALL_1(bpf_get_socket_cookie,struct sk_buff *,skb)4884 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
4885 {
4886 return skb->sk ? __sock_gen_cookie(skb->sk) : 0;
4887 }
4888
4889 static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
4890 .func = bpf_get_socket_cookie,
4891 .gpl_only = false,
4892 .ret_type = RET_INTEGER,
4893 .arg1_type = ARG_PTR_TO_CTX,
4894 };
4895
BPF_CALL_1(bpf_get_socket_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)4896 BPF_CALL_1(bpf_get_socket_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
4897 {
4898 return __sock_gen_cookie(ctx->sk);
4899 }
4900
4901 static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = {
4902 .func = bpf_get_socket_cookie_sock_addr,
4903 .gpl_only = false,
4904 .ret_type = RET_INTEGER,
4905 .arg1_type = ARG_PTR_TO_CTX,
4906 };
4907
BPF_CALL_1(bpf_get_socket_cookie_sock,struct sock *,ctx)4908 BPF_CALL_1(bpf_get_socket_cookie_sock, struct sock *, ctx)
4909 {
4910 return __sock_gen_cookie(ctx);
4911 }
4912
4913 static const struct bpf_func_proto bpf_get_socket_cookie_sock_proto = {
4914 .func = bpf_get_socket_cookie_sock,
4915 .gpl_only = false,
4916 .ret_type = RET_INTEGER,
4917 .arg1_type = ARG_PTR_TO_CTX,
4918 };
4919
BPF_CALL_1(bpf_get_socket_ptr_cookie,struct sock *,sk)4920 BPF_CALL_1(bpf_get_socket_ptr_cookie, struct sock *, sk)
4921 {
4922 return sk ? sock_gen_cookie(sk) : 0;
4923 }
4924
4925 const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto = {
4926 .func = bpf_get_socket_ptr_cookie,
4927 .gpl_only = false,
4928 .ret_type = RET_INTEGER,
4929 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
4930 };
4931
BPF_CALL_1(bpf_get_socket_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)4932 BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
4933 {
4934 return __sock_gen_cookie(ctx->sk);
4935 }
4936
4937 static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = {
4938 .func = bpf_get_socket_cookie_sock_ops,
4939 .gpl_only = false,
4940 .ret_type = RET_INTEGER,
4941 .arg1_type = ARG_PTR_TO_CTX,
4942 };
4943
__bpf_get_netns_cookie(struct sock * sk)4944 static u64 __bpf_get_netns_cookie(struct sock *sk)
4945 {
4946 const struct net *net = sk ? sock_net(sk) : &init_net;
4947
4948 return net->net_cookie;
4949 }
4950
BPF_CALL_1(bpf_get_netns_cookie_sock,struct sock *,ctx)4951 BPF_CALL_1(bpf_get_netns_cookie_sock, struct sock *, ctx)
4952 {
4953 return __bpf_get_netns_cookie(ctx);
4954 }
4955
4956 static const struct bpf_func_proto bpf_get_netns_cookie_sock_proto = {
4957 .func = bpf_get_netns_cookie_sock,
4958 .gpl_only = false,
4959 .ret_type = RET_INTEGER,
4960 .arg1_type = ARG_PTR_TO_CTX_OR_NULL,
4961 };
4962
BPF_CALL_1(bpf_get_netns_cookie_sock_addr,struct bpf_sock_addr_kern *,ctx)4963 BPF_CALL_1(bpf_get_netns_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
4964 {
4965 return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
4966 }
4967
4968 static const struct bpf_func_proto bpf_get_netns_cookie_sock_addr_proto = {
4969 .func = bpf_get_netns_cookie_sock_addr,
4970 .gpl_only = false,
4971 .ret_type = RET_INTEGER,
4972 .arg1_type = ARG_PTR_TO_CTX_OR_NULL,
4973 };
4974
BPF_CALL_1(bpf_get_netns_cookie_sock_ops,struct bpf_sock_ops_kern *,ctx)4975 BPF_CALL_1(bpf_get_netns_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
4976 {
4977 return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
4978 }
4979
4980 static const struct bpf_func_proto bpf_get_netns_cookie_sock_ops_proto = {
4981 .func = bpf_get_netns_cookie_sock_ops,
4982 .gpl_only = false,
4983 .ret_type = RET_INTEGER,
4984 .arg1_type = ARG_PTR_TO_CTX_OR_NULL,
4985 };
4986
BPF_CALL_1(bpf_get_netns_cookie_sk_msg,struct sk_msg *,ctx)4987 BPF_CALL_1(bpf_get_netns_cookie_sk_msg, struct sk_msg *, ctx)
4988 {
4989 return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
4990 }
4991
4992 static const struct bpf_func_proto bpf_get_netns_cookie_sk_msg_proto = {
4993 .func = bpf_get_netns_cookie_sk_msg,
4994 .gpl_only = false,
4995 .ret_type = RET_INTEGER,
4996 .arg1_type = ARG_PTR_TO_CTX_OR_NULL,
4997 };
4998
BPF_CALL_1(bpf_get_socket_uid,struct sk_buff *,skb)4999 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
5000 {
5001 struct sock *sk = sk_to_full_sk(skb->sk);
5002 kuid_t kuid;
5003
5004 if (!sk || !sk_fullsock(sk))
5005 return overflowuid;
5006 kuid = sock_net_uid(sock_net(sk), sk);
5007 return from_kuid_munged(sock_net(sk)->user_ns, kuid);
5008 }
5009
5010 static const struct bpf_func_proto bpf_get_socket_uid_proto = {
5011 .func = bpf_get_socket_uid,
5012 .gpl_only = false,
5013 .ret_type = RET_INTEGER,
5014 .arg1_type = ARG_PTR_TO_CTX,
5015 };
5016
_bpf_setsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5017 static int _bpf_setsockopt(struct sock *sk, int level, int optname,
5018 char *optval, int optlen)
5019 {
5020 char devname[IFNAMSIZ];
5021 int val, valbool;
5022 struct net *net;
5023 int ifindex;
5024 int ret = 0;
5025
5026 if (!sk_fullsock(sk))
5027 return -EINVAL;
5028
5029 sock_owned_by_me(sk);
5030
5031 if (level == SOL_SOCKET) {
5032 if (optlen != sizeof(int) && optname != SO_BINDTODEVICE)
5033 return -EINVAL;
5034 val = *((int *)optval);
5035 valbool = val ? 1 : 0;
5036
5037 /* Only some socketops are supported */
5038 switch (optname) {
5039 case SO_RCVBUF:
5040 val = min_t(u32, val, READ_ONCE(sysctl_rmem_max));
5041 val = min_t(int, val, INT_MAX / 2);
5042 sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
5043 WRITE_ONCE(sk->sk_rcvbuf,
5044 max_t(int, val * 2, SOCK_MIN_RCVBUF));
5045 break;
5046 case SO_SNDBUF:
5047 val = min_t(u32, val, READ_ONCE(sysctl_wmem_max));
5048 val = min_t(int, val, INT_MAX / 2);
5049 sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
5050 WRITE_ONCE(sk->sk_sndbuf,
5051 max_t(int, val * 2, SOCK_MIN_SNDBUF));
5052 break;
5053 case SO_MAX_PACING_RATE: /* 32bit version */
5054 if (val != ~0U)
5055 cmpxchg(&sk->sk_pacing_status,
5056 SK_PACING_NONE,
5057 SK_PACING_NEEDED);
5058 sk->sk_max_pacing_rate = (val == ~0U) ?
5059 ~0UL : (unsigned int)val;
5060 sk->sk_pacing_rate = min(sk->sk_pacing_rate,
5061 sk->sk_max_pacing_rate);
5062 break;
5063 case SO_PRIORITY:
5064 sk->sk_priority = val;
5065 break;
5066 case SO_RCVLOWAT:
5067 if (val < 0)
5068 val = INT_MAX;
5069 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
5070 break;
5071 case SO_MARK:
5072 if (sk->sk_mark != val) {
5073 sk->sk_mark = val;
5074 sk_dst_reset(sk);
5075 }
5076 break;
5077 case SO_BINDTODEVICE:
5078 optlen = min_t(long, optlen, IFNAMSIZ - 1);
5079 strncpy(devname, optval, optlen);
5080 devname[optlen] = 0;
5081
5082 ifindex = 0;
5083 if (devname[0] != '\0') {
5084 struct net_device *dev;
5085
5086 ret = -ENODEV;
5087
5088 net = sock_net(sk);
5089 dev = dev_get_by_name(net, devname);
5090 if (!dev)
5091 break;
5092 ifindex = dev->ifindex;
5093 dev_put(dev);
5094 }
5095 fallthrough;
5096 case SO_BINDTOIFINDEX:
5097 if (optname == SO_BINDTOIFINDEX)
5098 ifindex = val;
5099 ret = sock_bindtoindex(sk, ifindex, false);
5100 break;
5101 case SO_KEEPALIVE:
5102 if (sk->sk_prot->keepalive)
5103 sk->sk_prot->keepalive(sk, valbool);
5104 sock_valbool_flag(sk, SOCK_KEEPOPEN, valbool);
5105 break;
5106 case SO_REUSEPORT:
5107 sk->sk_reuseport = valbool;
5108 break;
5109 case SO_TXREHASH:
5110 if (val < -1 || val > 1) {
5111 ret = -EINVAL;
5112 break;
5113 }
5114 sk->sk_txrehash = (u8)val;
5115 break;
5116 default:
5117 ret = -EINVAL;
5118 }
5119 #ifdef CONFIG_INET
5120 } else if (level == SOL_IP) {
5121 if (optlen != sizeof(int) || sk->sk_family != AF_INET)
5122 return -EINVAL;
5123
5124 val = *((int *)optval);
5125 /* Only some options are supported */
5126 switch (optname) {
5127 case IP_TOS:
5128 if (val < -1 || val > 0xff) {
5129 ret = -EINVAL;
5130 } else {
5131 struct inet_sock *inet = inet_sk(sk);
5132
5133 if (val == -1)
5134 val = 0;
5135 inet->tos = val;
5136 }
5137 break;
5138 default:
5139 ret = -EINVAL;
5140 }
5141 #if IS_ENABLED(CONFIG_IPV6)
5142 } else if (level == SOL_IPV6) {
5143 if (optlen != sizeof(int) || sk->sk_family != AF_INET6)
5144 return -EINVAL;
5145
5146 val = *((int *)optval);
5147 /* Only some options are supported */
5148 switch (optname) {
5149 case IPV6_TCLASS:
5150 if (val < -1 || val > 0xff) {
5151 ret = -EINVAL;
5152 } else {
5153 struct ipv6_pinfo *np = inet6_sk(sk);
5154
5155 if (val == -1)
5156 val = 0;
5157 np->tclass = val;
5158 }
5159 break;
5160 default:
5161 ret = -EINVAL;
5162 }
5163 #endif
5164 } else if (level == SOL_TCP &&
5165 sk->sk_prot->setsockopt == tcp_setsockopt) {
5166 if (optname == TCP_CONGESTION) {
5167 char name[TCP_CA_NAME_MAX];
5168
5169 strncpy(name, optval, min_t(long, optlen,
5170 TCP_CA_NAME_MAX-1));
5171 name[TCP_CA_NAME_MAX-1] = 0;
5172 ret = tcp_set_congestion_control(sk, name, false, true);
5173 } else {
5174 struct inet_connection_sock *icsk = inet_csk(sk);
5175 struct tcp_sock *tp = tcp_sk(sk);
5176 unsigned long timeout;
5177
5178 if (optlen != sizeof(int))
5179 return -EINVAL;
5180
5181 val = *((int *)optval);
5182 /* Only some options are supported */
5183 switch (optname) {
5184 case TCP_BPF_IW:
5185 if (val <= 0 || tp->data_segs_out > tp->syn_data)
5186 ret = -EINVAL;
5187 else
5188 tcp_snd_cwnd_set(tp, val);
5189 break;
5190 case TCP_BPF_SNDCWND_CLAMP:
5191 if (val <= 0) {
5192 ret = -EINVAL;
5193 } else {
5194 tp->snd_cwnd_clamp = val;
5195 tp->snd_ssthresh = val;
5196 }
5197 break;
5198 case TCP_BPF_DELACK_MAX:
5199 timeout = usecs_to_jiffies(val);
5200 if (timeout > TCP_DELACK_MAX ||
5201 timeout < TCP_TIMEOUT_MIN)
5202 return -EINVAL;
5203 inet_csk(sk)->icsk_delack_max = timeout;
5204 break;
5205 case TCP_BPF_RTO_MIN:
5206 timeout = usecs_to_jiffies(val);
5207 if (timeout > TCP_RTO_MIN ||
5208 timeout < TCP_TIMEOUT_MIN)
5209 return -EINVAL;
5210 inet_csk(sk)->icsk_rto_min = timeout;
5211 break;
5212 case TCP_SAVE_SYN:
5213 if (val < 0 || val > 1)
5214 ret = -EINVAL;
5215 else
5216 tp->save_syn = val;
5217 break;
5218 case TCP_KEEPIDLE:
5219 ret = tcp_sock_set_keepidle_locked(sk, val);
5220 break;
5221 case TCP_KEEPINTVL:
5222 if (val < 1 || val > MAX_TCP_KEEPINTVL)
5223 ret = -EINVAL;
5224 else
5225 tp->keepalive_intvl = val * HZ;
5226 break;
5227 case TCP_KEEPCNT:
5228 if (val < 1 || val > MAX_TCP_KEEPCNT)
5229 ret = -EINVAL;
5230 else
5231 tp->keepalive_probes = val;
5232 break;
5233 case TCP_SYNCNT:
5234 if (val < 1 || val > MAX_TCP_SYNCNT)
5235 ret = -EINVAL;
5236 else
5237 icsk->icsk_syn_retries = val;
5238 break;
5239 case TCP_USER_TIMEOUT:
5240 if (val < 0)
5241 ret = -EINVAL;
5242 else
5243 icsk->icsk_user_timeout = val;
5244 break;
5245 case TCP_NOTSENT_LOWAT:
5246 tp->notsent_lowat = val;
5247 sk->sk_write_space(sk);
5248 break;
5249 case TCP_WINDOW_CLAMP:
5250 ret = tcp_set_window_clamp(sk, val);
5251 break;
5252 default:
5253 ret = -EINVAL;
5254 }
5255 }
5256 #endif
5257 } else {
5258 ret = -EINVAL;
5259 }
5260 return ret;
5261 }
5262
_bpf_getsockopt(struct sock * sk,int level,int optname,char * optval,int optlen)5263 static int _bpf_getsockopt(struct sock *sk, int level, int optname,
5264 char *optval, int optlen)
5265 {
5266 if (!sk_fullsock(sk))
5267 goto err_clear;
5268
5269 sock_owned_by_me(sk);
5270
5271 if (level == SOL_SOCKET) {
5272 if (optlen != sizeof(int))
5273 goto err_clear;
5274
5275 switch (optname) {
5276 case SO_RCVBUF:
5277 *((int *)optval) = sk->sk_rcvbuf;
5278 break;
5279 case SO_SNDBUF:
5280 *((int *)optval) = sk->sk_sndbuf;
5281 break;
5282 case SO_MARK:
5283 *((int *)optval) = sk->sk_mark;
5284 break;
5285 case SO_PRIORITY:
5286 *((int *)optval) = sk->sk_priority;
5287 break;
5288 case SO_BINDTOIFINDEX:
5289 *((int *)optval) = sk->sk_bound_dev_if;
5290 break;
5291 case SO_REUSEPORT:
5292 *((int *)optval) = sk->sk_reuseport;
5293 break;
5294 case SO_TXREHASH:
5295 *((int *)optval) = sk->sk_txrehash;
5296 break;
5297 default:
5298 goto err_clear;
5299 }
5300 #ifdef CONFIG_INET
5301 } else if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) {
5302 struct inet_connection_sock *icsk;
5303 struct tcp_sock *tp;
5304
5305 switch (optname) {
5306 case TCP_CONGESTION:
5307 icsk = inet_csk(sk);
5308
5309 if (!icsk->icsk_ca_ops || optlen <= 1)
5310 goto err_clear;
5311 strncpy(optval, icsk->icsk_ca_ops->name, optlen);
5312 optval[optlen - 1] = 0;
5313 break;
5314 case TCP_SAVED_SYN:
5315 tp = tcp_sk(sk);
5316
5317 if (optlen <= 0 || !tp->saved_syn ||
5318 optlen > tcp_saved_syn_len(tp->saved_syn))
5319 goto err_clear;
5320 memcpy(optval, tp->saved_syn->data, optlen);
5321 break;
5322 default:
5323 goto err_clear;
5324 }
5325 } else if (level == SOL_IP) {
5326 struct inet_sock *inet = inet_sk(sk);
5327
5328 if (optlen != sizeof(int) || sk->sk_family != AF_INET)
5329 goto err_clear;
5330
5331 /* Only some options are supported */
5332 switch (optname) {
5333 case IP_TOS:
5334 *((int *)optval) = (int)inet->tos;
5335 break;
5336 default:
5337 goto err_clear;
5338 }
5339 #if IS_ENABLED(CONFIG_IPV6)
5340 } else if (level == SOL_IPV6) {
5341 struct ipv6_pinfo *np = inet6_sk(sk);
5342
5343 if (optlen != sizeof(int) || sk->sk_family != AF_INET6)
5344 goto err_clear;
5345
5346 /* Only some options are supported */
5347 switch (optname) {
5348 case IPV6_TCLASS:
5349 *((int *)optval) = (int)np->tclass;
5350 break;
5351 default:
5352 goto err_clear;
5353 }
5354 #endif
5355 #endif
5356 } else {
5357 goto err_clear;
5358 }
5359 return 0;
5360 err_clear:
5361 memset(optval, 0, optlen);
5362 return -EINVAL;
5363 }
5364
BPF_CALL_5(bpf_sk_setsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5365 BPF_CALL_5(bpf_sk_setsockopt, struct sock *, sk, int, level,
5366 int, optname, char *, optval, int, optlen)
5367 {
5368 if (level == SOL_TCP && optname == TCP_CONGESTION) {
5369 if (optlen >= sizeof("cdg") - 1 &&
5370 !strncmp("cdg", optval, optlen))
5371 return -ENOTSUPP;
5372 }
5373
5374 return _bpf_setsockopt(sk, level, optname, optval, optlen);
5375 }
5376
5377 const struct bpf_func_proto bpf_sk_setsockopt_proto = {
5378 .func = bpf_sk_setsockopt,
5379 .gpl_only = false,
5380 .ret_type = RET_INTEGER,
5381 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5382 .arg2_type = ARG_ANYTHING,
5383 .arg3_type = ARG_ANYTHING,
5384 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
5385 .arg5_type = ARG_CONST_SIZE,
5386 };
5387
BPF_CALL_5(bpf_sk_getsockopt,struct sock *,sk,int,level,int,optname,char *,optval,int,optlen)5388 BPF_CALL_5(bpf_sk_getsockopt, struct sock *, sk, int, level,
5389 int, optname, char *, optval, int, optlen)
5390 {
5391 return _bpf_getsockopt(sk, level, optname, optval, optlen);
5392 }
5393
5394 const struct bpf_func_proto bpf_sk_getsockopt_proto = {
5395 .func = bpf_sk_getsockopt,
5396 .gpl_only = false,
5397 .ret_type = RET_INTEGER,
5398 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
5399 .arg2_type = ARG_ANYTHING,
5400 .arg3_type = ARG_ANYTHING,
5401 .arg4_type = ARG_PTR_TO_UNINIT_MEM,
5402 .arg5_type = ARG_CONST_SIZE,
5403 };
5404
BPF_CALL_5(bpf_sock_addr_setsockopt,struct bpf_sock_addr_kern *,ctx,int,level,int,optname,char *,optval,int,optlen)5405 BPF_CALL_5(bpf_sock_addr_setsockopt, struct bpf_sock_addr_kern *, ctx,
5406 int, level, int, optname, char *, optval, int, optlen)
5407 {
5408 return _bpf_setsockopt(ctx->sk, level, optname, optval, optlen);
5409 }
5410
5411 static const struct bpf_func_proto bpf_sock_addr_setsockopt_proto = {
5412 .func = bpf_sock_addr_setsockopt,
5413 .gpl_only = false,
5414 .ret_type = RET_INTEGER,
5415 .arg1_type = ARG_PTR_TO_CTX,
5416 .arg2_type = ARG_ANYTHING,
5417 .arg3_type = ARG_ANYTHING,
5418 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
5419 .arg5_type = ARG_CONST_SIZE,
5420 };
5421
BPF_CALL_5(bpf_sock_addr_getsockopt,struct bpf_sock_addr_kern *,ctx,int,level,int,optname,char *,optval,int,optlen)5422 BPF_CALL_5(bpf_sock_addr_getsockopt, struct bpf_sock_addr_kern *, ctx,
5423 int, level, int, optname, char *, optval, int, optlen)
5424 {
5425 return _bpf_getsockopt(ctx->sk, level, optname, optval, optlen);
5426 }
5427
5428 static const struct bpf_func_proto bpf_sock_addr_getsockopt_proto = {
5429 .func = bpf_sock_addr_getsockopt,
5430 .gpl_only = false,
5431 .ret_type = RET_INTEGER,
5432 .arg1_type = ARG_PTR_TO_CTX,
5433 .arg2_type = ARG_ANYTHING,
5434 .arg3_type = ARG_ANYTHING,
5435 .arg4_type = ARG_PTR_TO_UNINIT_MEM,
5436 .arg5_type = ARG_CONST_SIZE,
5437 };
5438
BPF_CALL_5(bpf_sock_ops_setsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)5439 BPF_CALL_5(bpf_sock_ops_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
5440 int, level, int, optname, char *, optval, int, optlen)
5441 {
5442 return _bpf_setsockopt(bpf_sock->sk, level, optname, optval, optlen);
5443 }
5444
5445 static const struct bpf_func_proto bpf_sock_ops_setsockopt_proto = {
5446 .func = bpf_sock_ops_setsockopt,
5447 .gpl_only = false,
5448 .ret_type = RET_INTEGER,
5449 .arg1_type = ARG_PTR_TO_CTX,
5450 .arg2_type = ARG_ANYTHING,
5451 .arg3_type = ARG_ANYTHING,
5452 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
5453 .arg5_type = ARG_CONST_SIZE,
5454 };
5455
bpf_sock_ops_get_syn(struct bpf_sock_ops_kern * bpf_sock,int optname,const u8 ** start)5456 static int bpf_sock_ops_get_syn(struct bpf_sock_ops_kern *bpf_sock,
5457 int optname, const u8 **start)
5458 {
5459 struct sk_buff *syn_skb = bpf_sock->syn_skb;
5460 const u8 *hdr_start;
5461 int ret;
5462
5463 if (syn_skb) {
5464 /* sk is a request_sock here */
5465
5466 if (optname == TCP_BPF_SYN) {
5467 hdr_start = syn_skb->data;
5468 ret = tcp_hdrlen(syn_skb);
5469 } else if (optname == TCP_BPF_SYN_IP) {
5470 hdr_start = skb_network_header(syn_skb);
5471 ret = skb_network_header_len(syn_skb) +
5472 tcp_hdrlen(syn_skb);
5473 } else {
5474 /* optname == TCP_BPF_SYN_MAC */
5475 hdr_start = skb_mac_header(syn_skb);
5476 ret = skb_mac_header_len(syn_skb) +
5477 skb_network_header_len(syn_skb) +
5478 tcp_hdrlen(syn_skb);
5479 }
5480 } else {
5481 struct sock *sk = bpf_sock->sk;
5482 struct saved_syn *saved_syn;
5483
5484 if (sk->sk_state == TCP_NEW_SYN_RECV)
5485 /* synack retransmit. bpf_sock->syn_skb will
5486 * not be available. It has to resort to
5487 * saved_syn (if it is saved).
5488 */
5489 saved_syn = inet_reqsk(sk)->saved_syn;
5490 else
5491 saved_syn = tcp_sk(sk)->saved_syn;
5492
5493 if (!saved_syn)
5494 return -ENOENT;
5495
5496 if (optname == TCP_BPF_SYN) {
5497 hdr_start = saved_syn->data +
5498 saved_syn->mac_hdrlen +
5499 saved_syn->network_hdrlen;
5500 ret = saved_syn->tcp_hdrlen;
5501 } else if (optname == TCP_BPF_SYN_IP) {
5502 hdr_start = saved_syn->data +
5503 saved_syn->mac_hdrlen;
5504 ret = saved_syn->network_hdrlen +
5505 saved_syn->tcp_hdrlen;
5506 } else {
5507 /* optname == TCP_BPF_SYN_MAC */
5508
5509 /* TCP_SAVE_SYN may not have saved the mac hdr */
5510 if (!saved_syn->mac_hdrlen)
5511 return -ENOENT;
5512
5513 hdr_start = saved_syn->data;
5514 ret = saved_syn->mac_hdrlen +
5515 saved_syn->network_hdrlen +
5516 saved_syn->tcp_hdrlen;
5517 }
5518 }
5519
5520 *start = hdr_start;
5521 return ret;
5522 }
5523
BPF_CALL_5(bpf_sock_ops_getsockopt,struct bpf_sock_ops_kern *,bpf_sock,int,level,int,optname,char *,optval,int,optlen)5524 BPF_CALL_5(bpf_sock_ops_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
5525 int, level, int, optname, char *, optval, int, optlen)
5526 {
5527 if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP &&
5528 optname >= TCP_BPF_SYN && optname <= TCP_BPF_SYN_MAC) {
5529 int ret, copy_len = 0;
5530 const u8 *start;
5531
5532 ret = bpf_sock_ops_get_syn(bpf_sock, optname, &start);
5533 if (ret > 0) {
5534 copy_len = ret;
5535 if (optlen < copy_len) {
5536 copy_len = optlen;
5537 ret = -ENOSPC;
5538 }
5539
5540 memcpy(optval, start, copy_len);
5541 }
5542
5543 /* Zero out unused buffer at the end */
5544 memset(optval + copy_len, 0, optlen - copy_len);
5545
5546 return ret;
5547 }
5548
5549 return _bpf_getsockopt(bpf_sock->sk, level, optname, optval, optlen);
5550 }
5551
5552 static const struct bpf_func_proto bpf_sock_ops_getsockopt_proto = {
5553 .func = bpf_sock_ops_getsockopt,
5554 .gpl_only = false,
5555 .ret_type = RET_INTEGER,
5556 .arg1_type = ARG_PTR_TO_CTX,
5557 .arg2_type = ARG_ANYTHING,
5558 .arg3_type = ARG_ANYTHING,
5559 .arg4_type = ARG_PTR_TO_UNINIT_MEM,
5560 .arg5_type = ARG_CONST_SIZE,
5561 };
5562
BPF_CALL_2(bpf_sock_ops_cb_flags_set,struct bpf_sock_ops_kern *,bpf_sock,int,argval)5563 BPF_CALL_2(bpf_sock_ops_cb_flags_set, struct bpf_sock_ops_kern *, bpf_sock,
5564 int, argval)
5565 {
5566 struct sock *sk = bpf_sock->sk;
5567 int val = argval & BPF_SOCK_OPS_ALL_CB_FLAGS;
5568
5569 if (!IS_ENABLED(CONFIG_INET) || !sk_fullsock(sk))
5570 return -EINVAL;
5571
5572 tcp_sk(sk)->bpf_sock_ops_cb_flags = val;
5573
5574 return argval & (~BPF_SOCK_OPS_ALL_CB_FLAGS);
5575 }
5576
5577 static const struct bpf_func_proto bpf_sock_ops_cb_flags_set_proto = {
5578 .func = bpf_sock_ops_cb_flags_set,
5579 .gpl_only = false,
5580 .ret_type = RET_INTEGER,
5581 .arg1_type = ARG_PTR_TO_CTX,
5582 .arg2_type = ARG_ANYTHING,
5583 };
5584
5585 const struct ipv6_bpf_stub *ipv6_bpf_stub __read_mostly;
5586 EXPORT_SYMBOL_GPL(ipv6_bpf_stub);
5587
BPF_CALL_3(bpf_bind,struct bpf_sock_addr_kern *,ctx,struct sockaddr *,addr,int,addr_len)5588 BPF_CALL_3(bpf_bind, struct bpf_sock_addr_kern *, ctx, struct sockaddr *, addr,
5589 int, addr_len)
5590 {
5591 #ifdef CONFIG_INET
5592 struct sock *sk = ctx->sk;
5593 u32 flags = BIND_FROM_BPF;
5594 int err;
5595
5596 err = -EINVAL;
5597 if (addr_len < offsetofend(struct sockaddr, sa_family))
5598 return err;
5599 if (addr->sa_family == AF_INET) {
5600 if (addr_len < sizeof(struct sockaddr_in))
5601 return err;
5602 if (((struct sockaddr_in *)addr)->sin_port == htons(0))
5603 flags |= BIND_FORCE_ADDRESS_NO_PORT;
5604 return __inet_bind(sk, addr, addr_len, flags);
5605 #if IS_ENABLED(CONFIG_IPV6)
5606 } else if (addr->sa_family == AF_INET6) {
5607 if (addr_len < SIN6_LEN_RFC2133)
5608 return err;
5609 if (((struct sockaddr_in6 *)addr)->sin6_port == htons(0))
5610 flags |= BIND_FORCE_ADDRESS_NO_PORT;
5611 /* ipv6_bpf_stub cannot be NULL, since it's called from
5612 * bpf_cgroup_inet6_connect hook and ipv6 is already loaded
5613 */
5614 return ipv6_bpf_stub->inet6_bind(sk, addr, addr_len, flags);
5615 #endif /* CONFIG_IPV6 */
5616 }
5617 #endif /* CONFIG_INET */
5618
5619 return -EAFNOSUPPORT;
5620 }
5621
5622 static const struct bpf_func_proto bpf_bind_proto = {
5623 .func = bpf_bind,
5624 .gpl_only = false,
5625 .ret_type = RET_INTEGER,
5626 .arg1_type = ARG_PTR_TO_CTX,
5627 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
5628 .arg3_type = ARG_CONST_SIZE,
5629 };
5630
5631 #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)5632 BPF_CALL_5(bpf_skb_get_xfrm_state, struct sk_buff *, skb, u32, index,
5633 struct bpf_xfrm_state *, to, u32, size, u64, flags)
5634 {
5635 const struct sec_path *sp = skb_sec_path(skb);
5636 const struct xfrm_state *x;
5637
5638 if (!sp || unlikely(index >= sp->len || flags))
5639 goto err_clear;
5640
5641 x = sp->xvec[index];
5642
5643 if (unlikely(size != sizeof(struct bpf_xfrm_state)))
5644 goto err_clear;
5645
5646 to->reqid = x->props.reqid;
5647 to->spi = x->id.spi;
5648 to->family = x->props.family;
5649 to->ext = 0;
5650
5651 if (to->family == AF_INET6) {
5652 memcpy(to->remote_ipv6, x->props.saddr.a6,
5653 sizeof(to->remote_ipv6));
5654 } else {
5655 to->remote_ipv4 = x->props.saddr.a4;
5656 memset(&to->remote_ipv6[1], 0, sizeof(__u32) * 3);
5657 }
5658
5659 return 0;
5660 err_clear:
5661 memset(to, 0, size);
5662 return -EINVAL;
5663 }
5664
5665 static const struct bpf_func_proto bpf_skb_get_xfrm_state_proto = {
5666 .func = bpf_skb_get_xfrm_state,
5667 .gpl_only = false,
5668 .ret_type = RET_INTEGER,
5669 .arg1_type = ARG_PTR_TO_CTX,
5670 .arg2_type = ARG_ANYTHING,
5671 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
5672 .arg4_type = ARG_CONST_SIZE,
5673 .arg5_type = ARG_ANYTHING,
5674 };
5675 #endif
5676
5677 #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)5678 static int bpf_fib_set_fwd_params(struct bpf_fib_lookup *params,
5679 const struct neighbour *neigh,
5680 const struct net_device *dev, u32 mtu)
5681 {
5682 memcpy(params->dmac, neigh->ha, ETH_ALEN);
5683 memcpy(params->smac, dev->dev_addr, ETH_ALEN);
5684 params->h_vlan_TCI = 0;
5685 params->h_vlan_proto = 0;
5686 if (mtu)
5687 params->mtu_result = mtu; /* union with tot_len */
5688
5689 return 0;
5690 }
5691 #endif
5692
5693 #if IS_ENABLED(CONFIG_INET)
bpf_ipv4_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)5694 static int bpf_ipv4_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
5695 u32 flags, bool check_mtu)
5696 {
5697 struct fib_nh_common *nhc;
5698 struct in_device *in_dev;
5699 struct neighbour *neigh;
5700 struct net_device *dev;
5701 struct fib_result res;
5702 struct flowi4 fl4;
5703 u32 mtu = 0;
5704 int err;
5705
5706 dev = dev_get_by_index_rcu(net, params->ifindex);
5707 if (unlikely(!dev))
5708 return -ENODEV;
5709
5710 /* verify forwarding is enabled on this interface */
5711 in_dev = __in_dev_get_rcu(dev);
5712 if (unlikely(!in_dev || !IN_DEV_FORWARD(in_dev)))
5713 return BPF_FIB_LKUP_RET_FWD_DISABLED;
5714
5715 if (flags & BPF_FIB_LOOKUP_OUTPUT) {
5716 fl4.flowi4_iif = 1;
5717 fl4.flowi4_oif = params->ifindex;
5718 } else {
5719 fl4.flowi4_iif = params->ifindex;
5720 fl4.flowi4_oif = 0;
5721 }
5722 fl4.flowi4_tos = params->tos & IPTOS_RT_MASK;
5723 fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
5724 fl4.flowi4_flags = 0;
5725
5726 fl4.flowi4_proto = params->l4_protocol;
5727 fl4.daddr = params->ipv4_dst;
5728 fl4.saddr = params->ipv4_src;
5729 fl4.fl4_sport = params->sport;
5730 fl4.fl4_dport = params->dport;
5731 fl4.flowi4_multipath_hash = 0;
5732
5733 if (flags & BPF_FIB_LOOKUP_DIRECT) {
5734 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
5735 struct fib_table *tb;
5736
5737 tb = fib_get_table(net, tbid);
5738 if (unlikely(!tb))
5739 return BPF_FIB_LKUP_RET_NOT_FWDED;
5740
5741 err = fib_table_lookup(tb, &fl4, &res, FIB_LOOKUP_NOREF);
5742 } else {
5743 fl4.flowi4_mark = 0;
5744 fl4.flowi4_secid = 0;
5745 fl4.flowi4_tun_key.tun_id = 0;
5746 fl4.flowi4_uid = sock_net_uid(net, NULL);
5747
5748 err = fib_lookup(net, &fl4, &res, FIB_LOOKUP_NOREF);
5749 }
5750
5751 if (err) {
5752 /* map fib lookup errors to RTN_ type */
5753 if (err == -EINVAL)
5754 return BPF_FIB_LKUP_RET_BLACKHOLE;
5755 if (err == -EHOSTUNREACH)
5756 return BPF_FIB_LKUP_RET_UNREACHABLE;
5757 if (err == -EACCES)
5758 return BPF_FIB_LKUP_RET_PROHIBIT;
5759
5760 return BPF_FIB_LKUP_RET_NOT_FWDED;
5761 }
5762
5763 if (res.type != RTN_UNICAST)
5764 return BPF_FIB_LKUP_RET_NOT_FWDED;
5765
5766 if (fib_info_num_path(res.fi) > 1)
5767 fib_select_path(net, &res, &fl4, NULL);
5768
5769 if (check_mtu) {
5770 mtu = ip_mtu_from_fib_result(&res, params->ipv4_dst);
5771 if (params->tot_len > mtu) {
5772 params->mtu_result = mtu; /* union with tot_len */
5773 return BPF_FIB_LKUP_RET_FRAG_NEEDED;
5774 }
5775 }
5776
5777 nhc = res.nhc;
5778
5779 /* do not handle lwt encaps right now */
5780 if (nhc->nhc_lwtstate)
5781 return BPF_FIB_LKUP_RET_UNSUPP_LWT;
5782
5783 dev = nhc->nhc_dev;
5784
5785 params->rt_metric = res.fi->fib_priority;
5786 params->ifindex = dev->ifindex;
5787
5788 /* xdp and cls_bpf programs are run in RCU-bh so
5789 * rcu_read_lock_bh is not needed here
5790 */
5791 if (likely(nhc->nhc_gw_family != AF_INET6)) {
5792 if (nhc->nhc_gw_family)
5793 params->ipv4_dst = nhc->nhc_gw.ipv4;
5794
5795 neigh = __ipv4_neigh_lookup_noref(dev,
5796 (__force u32)params->ipv4_dst);
5797 } else {
5798 struct in6_addr *dst = (struct in6_addr *)params->ipv6_dst;
5799
5800 params->family = AF_INET6;
5801 *dst = nhc->nhc_gw.ipv6;
5802 neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
5803 }
5804
5805 if (!neigh)
5806 return BPF_FIB_LKUP_RET_NO_NEIGH;
5807
5808 return bpf_fib_set_fwd_params(params, neigh, dev, mtu);
5809 }
5810 #endif
5811
5812 #if IS_ENABLED(CONFIG_IPV6)
bpf_ipv6_fib_lookup(struct net * net,struct bpf_fib_lookup * params,u32 flags,bool check_mtu)5813 static int bpf_ipv6_fib_lookup(struct net *net, struct bpf_fib_lookup *params,
5814 u32 flags, bool check_mtu)
5815 {
5816 struct in6_addr *src = (struct in6_addr *) params->ipv6_src;
5817 struct in6_addr *dst = (struct in6_addr *) params->ipv6_dst;
5818 struct fib6_result res = {};
5819 struct neighbour *neigh;
5820 struct net_device *dev;
5821 struct inet6_dev *idev;
5822 struct flowi6 fl6;
5823 int strict = 0;
5824 int oif, err;
5825 u32 mtu = 0;
5826
5827 /* link local addresses are never forwarded */
5828 if (rt6_need_strict(dst) || rt6_need_strict(src))
5829 return BPF_FIB_LKUP_RET_NOT_FWDED;
5830
5831 dev = dev_get_by_index_rcu(net, params->ifindex);
5832 if (unlikely(!dev))
5833 return -ENODEV;
5834
5835 idev = __in6_dev_get_safely(dev);
5836 if (unlikely(!idev || !idev->cnf.forwarding))
5837 return BPF_FIB_LKUP_RET_FWD_DISABLED;
5838
5839 if (flags & BPF_FIB_LOOKUP_OUTPUT) {
5840 fl6.flowi6_iif = 1;
5841 oif = fl6.flowi6_oif = params->ifindex;
5842 } else {
5843 oif = fl6.flowi6_iif = params->ifindex;
5844 fl6.flowi6_oif = 0;
5845 strict = RT6_LOOKUP_F_HAS_SADDR;
5846 }
5847 fl6.flowlabel = params->flowinfo;
5848 fl6.flowi6_scope = 0;
5849 fl6.flowi6_flags = 0;
5850 fl6.mp_hash = 0;
5851
5852 fl6.flowi6_proto = params->l4_protocol;
5853 fl6.daddr = *dst;
5854 fl6.saddr = *src;
5855 fl6.fl6_sport = params->sport;
5856 fl6.fl6_dport = params->dport;
5857
5858 if (flags & BPF_FIB_LOOKUP_DIRECT) {
5859 u32 tbid = l3mdev_fib_table_rcu(dev) ? : RT_TABLE_MAIN;
5860 struct fib6_table *tb;
5861
5862 tb = ipv6_stub->fib6_get_table(net, tbid);
5863 if (unlikely(!tb))
5864 return BPF_FIB_LKUP_RET_NOT_FWDED;
5865
5866 err = ipv6_stub->fib6_table_lookup(net, tb, oif, &fl6, &res,
5867 strict);
5868 } else {
5869 fl6.flowi6_mark = 0;
5870 fl6.flowi6_secid = 0;
5871 fl6.flowi6_tun_key.tun_id = 0;
5872 fl6.flowi6_uid = sock_net_uid(net, NULL);
5873
5874 err = ipv6_stub->fib6_lookup(net, oif, &fl6, &res, strict);
5875 }
5876
5877 if (unlikely(err || IS_ERR_OR_NULL(res.f6i) ||
5878 res.f6i == net->ipv6.fib6_null_entry))
5879 return BPF_FIB_LKUP_RET_NOT_FWDED;
5880
5881 switch (res.fib6_type) {
5882 /* only unicast is forwarded */
5883 case RTN_UNICAST:
5884 break;
5885 case RTN_BLACKHOLE:
5886 return BPF_FIB_LKUP_RET_BLACKHOLE;
5887 case RTN_UNREACHABLE:
5888 return BPF_FIB_LKUP_RET_UNREACHABLE;
5889 case RTN_PROHIBIT:
5890 return BPF_FIB_LKUP_RET_PROHIBIT;
5891 default:
5892 return BPF_FIB_LKUP_RET_NOT_FWDED;
5893 }
5894
5895 ipv6_stub->fib6_select_path(net, &res, &fl6, fl6.flowi6_oif,
5896 fl6.flowi6_oif != 0, NULL, strict);
5897
5898 if (check_mtu) {
5899 mtu = ipv6_stub->ip6_mtu_from_fib6(&res, dst, src);
5900 if (params->tot_len > mtu) {
5901 params->mtu_result = mtu; /* union with tot_len */
5902 return BPF_FIB_LKUP_RET_FRAG_NEEDED;
5903 }
5904 }
5905
5906 if (res.nh->fib_nh_lws)
5907 return BPF_FIB_LKUP_RET_UNSUPP_LWT;
5908
5909 if (res.nh->fib_nh_gw_family)
5910 *dst = res.nh->fib_nh_gw6;
5911
5912 dev = res.nh->fib_nh_dev;
5913 params->rt_metric = res.f6i->fib6_metric;
5914 params->ifindex = dev->ifindex;
5915
5916 /* xdp and cls_bpf programs are run in RCU-bh so rcu_read_lock_bh is
5917 * not needed here.
5918 */
5919 neigh = __ipv6_neigh_lookup_noref_stub(dev, dst);
5920 if (!neigh)
5921 return BPF_FIB_LKUP_RET_NO_NEIGH;
5922
5923 return bpf_fib_set_fwd_params(params, neigh, dev, mtu);
5924 }
5925 #endif
5926
BPF_CALL_4(bpf_xdp_fib_lookup,struct xdp_buff *,ctx,struct bpf_fib_lookup *,params,int,plen,u32,flags)5927 BPF_CALL_4(bpf_xdp_fib_lookup, struct xdp_buff *, ctx,
5928 struct bpf_fib_lookup *, params, int, plen, u32, flags)
5929 {
5930 if (plen < sizeof(*params))
5931 return -EINVAL;
5932
5933 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT))
5934 return -EINVAL;
5935
5936 switch (params->family) {
5937 #if IS_ENABLED(CONFIG_INET)
5938 case AF_INET:
5939 return bpf_ipv4_fib_lookup(dev_net(ctx->rxq->dev), params,
5940 flags, true);
5941 #endif
5942 #if IS_ENABLED(CONFIG_IPV6)
5943 case AF_INET6:
5944 return bpf_ipv6_fib_lookup(dev_net(ctx->rxq->dev), params,
5945 flags, true);
5946 #endif
5947 }
5948 return -EAFNOSUPPORT;
5949 }
5950
5951 static const struct bpf_func_proto bpf_xdp_fib_lookup_proto = {
5952 .func = bpf_xdp_fib_lookup,
5953 .gpl_only = true,
5954 .ret_type = RET_INTEGER,
5955 .arg1_type = ARG_PTR_TO_CTX,
5956 .arg2_type = ARG_PTR_TO_MEM,
5957 .arg3_type = ARG_CONST_SIZE,
5958 .arg4_type = ARG_ANYTHING,
5959 };
5960
BPF_CALL_4(bpf_skb_fib_lookup,struct sk_buff *,skb,struct bpf_fib_lookup *,params,int,plen,u32,flags)5961 BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
5962 struct bpf_fib_lookup *, params, int, plen, u32, flags)
5963 {
5964 struct net *net = dev_net(skb->dev);
5965 int rc = -EAFNOSUPPORT;
5966 bool check_mtu = false;
5967
5968 if (plen < sizeof(*params))
5969 return -EINVAL;
5970
5971 if (flags & ~(BPF_FIB_LOOKUP_DIRECT | BPF_FIB_LOOKUP_OUTPUT))
5972 return -EINVAL;
5973
5974 if (params->tot_len)
5975 check_mtu = true;
5976
5977 switch (params->family) {
5978 #if IS_ENABLED(CONFIG_INET)
5979 case AF_INET:
5980 rc = bpf_ipv4_fib_lookup(net, params, flags, check_mtu);
5981 break;
5982 #endif
5983 #if IS_ENABLED(CONFIG_IPV6)
5984 case AF_INET6:
5985 rc = bpf_ipv6_fib_lookup(net, params, flags, check_mtu);
5986 break;
5987 #endif
5988 }
5989
5990 if (rc == BPF_FIB_LKUP_RET_SUCCESS && !check_mtu) {
5991 struct net_device *dev;
5992
5993 /* When tot_len isn't provided by user, check skb
5994 * against MTU of FIB lookup resulting net_device
5995 */
5996 dev = dev_get_by_index_rcu(net, params->ifindex);
5997 if (!is_skb_forwardable(dev, skb))
5998 rc = BPF_FIB_LKUP_RET_FRAG_NEEDED;
5999
6000 params->mtu_result = dev->mtu; /* union with tot_len */
6001 }
6002
6003 return rc;
6004 }
6005
6006 static const struct bpf_func_proto bpf_skb_fib_lookup_proto = {
6007 .func = bpf_skb_fib_lookup,
6008 .gpl_only = true,
6009 .ret_type = RET_INTEGER,
6010 .arg1_type = ARG_PTR_TO_CTX,
6011 .arg2_type = ARG_PTR_TO_MEM,
6012 .arg3_type = ARG_CONST_SIZE,
6013 .arg4_type = ARG_ANYTHING,
6014 };
6015
__dev_via_ifindex(struct net_device * dev_curr,u32 ifindex)6016 static struct net_device *__dev_via_ifindex(struct net_device *dev_curr,
6017 u32 ifindex)
6018 {
6019 struct net *netns = dev_net(dev_curr);
6020
6021 /* Non-redirect use-cases can use ifindex=0 and save ifindex lookup */
6022 if (ifindex == 0)
6023 return dev_curr;
6024
6025 return dev_get_by_index_rcu(netns, ifindex);
6026 }
6027
BPF_CALL_5(bpf_skb_check_mtu,struct sk_buff *,skb,u32,ifindex,u32 *,mtu_len,s32,len_diff,u64,flags)6028 BPF_CALL_5(bpf_skb_check_mtu, struct sk_buff *, skb,
6029 u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
6030 {
6031 int ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
6032 struct net_device *dev = skb->dev;
6033 int skb_len, dev_len;
6034 int mtu;
6035
6036 if (unlikely(flags & ~(BPF_MTU_CHK_SEGS)))
6037 return -EINVAL;
6038
6039 if (unlikely(flags & BPF_MTU_CHK_SEGS && (len_diff || *mtu_len)))
6040 return -EINVAL;
6041
6042 dev = __dev_via_ifindex(dev, ifindex);
6043 if (unlikely(!dev))
6044 return -ENODEV;
6045
6046 mtu = READ_ONCE(dev->mtu);
6047
6048 dev_len = mtu + dev->hard_header_len;
6049
6050 /* If set use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
6051 skb_len = *mtu_len ? *mtu_len + dev->hard_header_len : skb->len;
6052
6053 skb_len += len_diff; /* minus result pass check */
6054 if (skb_len <= dev_len) {
6055 ret = BPF_MTU_CHK_RET_SUCCESS;
6056 goto out;
6057 }
6058 /* At this point, skb->len exceed MTU, but as it include length of all
6059 * segments, it can still be below MTU. The SKB can possibly get
6060 * re-segmented in transmit path (see validate_xmit_skb). Thus, user
6061 * must choose if segs are to be MTU checked.
6062 */
6063 if (skb_is_gso(skb)) {
6064 ret = BPF_MTU_CHK_RET_SUCCESS;
6065
6066 if (flags & BPF_MTU_CHK_SEGS &&
6067 !skb_gso_validate_network_len(skb, mtu))
6068 ret = BPF_MTU_CHK_RET_SEGS_TOOBIG;
6069 }
6070 out:
6071 /* BPF verifier guarantees valid pointer */
6072 *mtu_len = mtu;
6073
6074 return ret;
6075 }
6076
BPF_CALL_5(bpf_xdp_check_mtu,struct xdp_buff *,xdp,u32,ifindex,u32 *,mtu_len,s32,len_diff,u64,flags)6077 BPF_CALL_5(bpf_xdp_check_mtu, struct xdp_buff *, xdp,
6078 u32, ifindex, u32 *, mtu_len, s32, len_diff, u64, flags)
6079 {
6080 struct net_device *dev = xdp->rxq->dev;
6081 int xdp_len = xdp->data_end - xdp->data;
6082 int ret = BPF_MTU_CHK_RET_SUCCESS;
6083 int mtu, dev_len;
6084
6085 /* XDP variant doesn't support multi-buffer segment check (yet) */
6086 if (unlikely(flags))
6087 return -EINVAL;
6088
6089 dev = __dev_via_ifindex(dev, ifindex);
6090 if (unlikely(!dev))
6091 return -ENODEV;
6092
6093 mtu = READ_ONCE(dev->mtu);
6094
6095 /* Add L2-header as dev MTU is L3 size */
6096 dev_len = mtu + dev->hard_header_len;
6097
6098 /* Use *mtu_len as input, L3 as iph->tot_len (like fib_lookup) */
6099 if (*mtu_len)
6100 xdp_len = *mtu_len + dev->hard_header_len;
6101
6102 xdp_len += len_diff; /* minus result pass check */
6103 if (xdp_len > dev_len)
6104 ret = BPF_MTU_CHK_RET_FRAG_NEEDED;
6105
6106 /* BPF verifier guarantees valid pointer */
6107 *mtu_len = mtu;
6108
6109 return ret;
6110 }
6111
6112 static const struct bpf_func_proto bpf_skb_check_mtu_proto = {
6113 .func = bpf_skb_check_mtu,
6114 .gpl_only = true,
6115 .ret_type = RET_INTEGER,
6116 .arg1_type = ARG_PTR_TO_CTX,
6117 .arg2_type = ARG_ANYTHING,
6118 .arg3_type = ARG_PTR_TO_INT,
6119 .arg4_type = ARG_ANYTHING,
6120 .arg5_type = ARG_ANYTHING,
6121 };
6122
6123 static const struct bpf_func_proto bpf_xdp_check_mtu_proto = {
6124 .func = bpf_xdp_check_mtu,
6125 .gpl_only = true,
6126 .ret_type = RET_INTEGER,
6127 .arg1_type = ARG_PTR_TO_CTX,
6128 .arg2_type = ARG_ANYTHING,
6129 .arg3_type = ARG_PTR_TO_INT,
6130 .arg4_type = ARG_ANYTHING,
6131 .arg5_type = ARG_ANYTHING,
6132 };
6133
6134 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
bpf_push_seg6_encap(struct sk_buff * skb,u32 type,void * hdr,u32 len)6135 static int bpf_push_seg6_encap(struct sk_buff *skb, u32 type, void *hdr, u32 len)
6136 {
6137 int err;
6138 struct ipv6_sr_hdr *srh = (struct ipv6_sr_hdr *)hdr;
6139
6140 if (!seg6_validate_srh(srh, len, false))
6141 return -EINVAL;
6142
6143 switch (type) {
6144 case BPF_LWT_ENCAP_SEG6_INLINE:
6145 if (skb->protocol != htons(ETH_P_IPV6))
6146 return -EBADMSG;
6147
6148 err = seg6_do_srh_inline(skb, srh);
6149 break;
6150 case BPF_LWT_ENCAP_SEG6:
6151 skb_reset_inner_headers(skb);
6152 skb->encapsulation = 1;
6153 err = seg6_do_srh_encap(skb, srh, IPPROTO_IPV6);
6154 break;
6155 default:
6156 return -EINVAL;
6157 }
6158
6159 bpf_compute_data_pointers(skb);
6160 if (err)
6161 return err;
6162
6163 skb_set_transport_header(skb, sizeof(struct ipv6hdr));
6164
6165 return seg6_lookup_nexthop(skb, NULL, 0);
6166 }
6167 #endif /* CONFIG_IPV6_SEG6_BPF */
6168
6169 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
bpf_push_ip_encap(struct sk_buff * skb,void * hdr,u32 len,bool ingress)6170 static int bpf_push_ip_encap(struct sk_buff *skb, void *hdr, u32 len,
6171 bool ingress)
6172 {
6173 return bpf_lwt_push_ip_encap(skb, hdr, len, ingress);
6174 }
6175 #endif
6176
BPF_CALL_4(bpf_lwt_in_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)6177 BPF_CALL_4(bpf_lwt_in_push_encap, struct sk_buff *, skb, u32, type, void *, hdr,
6178 u32, len)
6179 {
6180 switch (type) {
6181 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
6182 case BPF_LWT_ENCAP_SEG6:
6183 case BPF_LWT_ENCAP_SEG6_INLINE:
6184 return bpf_push_seg6_encap(skb, type, hdr, len);
6185 #endif
6186 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
6187 case BPF_LWT_ENCAP_IP:
6188 return bpf_push_ip_encap(skb, hdr, len, true /* ingress */);
6189 #endif
6190 default:
6191 return -EINVAL;
6192 }
6193 }
6194
BPF_CALL_4(bpf_lwt_xmit_push_encap,struct sk_buff *,skb,u32,type,void *,hdr,u32,len)6195 BPF_CALL_4(bpf_lwt_xmit_push_encap, struct sk_buff *, skb, u32, type,
6196 void *, hdr, u32, len)
6197 {
6198 switch (type) {
6199 #if IS_ENABLED(CONFIG_LWTUNNEL_BPF)
6200 case BPF_LWT_ENCAP_IP:
6201 return bpf_push_ip_encap(skb, hdr, len, false /* egress */);
6202 #endif
6203 default:
6204 return -EINVAL;
6205 }
6206 }
6207
6208 static const struct bpf_func_proto bpf_lwt_in_push_encap_proto = {
6209 .func = bpf_lwt_in_push_encap,
6210 .gpl_only = false,
6211 .ret_type = RET_INTEGER,
6212 .arg1_type = ARG_PTR_TO_CTX,
6213 .arg2_type = ARG_ANYTHING,
6214 .arg3_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6215 .arg4_type = ARG_CONST_SIZE
6216 };
6217
6218 static const struct bpf_func_proto bpf_lwt_xmit_push_encap_proto = {
6219 .func = bpf_lwt_xmit_push_encap,
6220 .gpl_only = false,
6221 .ret_type = RET_INTEGER,
6222 .arg1_type = ARG_PTR_TO_CTX,
6223 .arg2_type = ARG_ANYTHING,
6224 .arg3_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6225 .arg4_type = ARG_CONST_SIZE
6226 };
6227
6228 #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)6229 BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset,
6230 const void *, from, u32, len)
6231 {
6232 struct seg6_bpf_srh_state *srh_state =
6233 this_cpu_ptr(&seg6_bpf_srh_states);
6234 struct ipv6_sr_hdr *srh = srh_state->srh;
6235 void *srh_tlvs, *srh_end, *ptr;
6236 int srhoff = 0;
6237
6238 if (srh == NULL)
6239 return -EINVAL;
6240
6241 srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4));
6242 srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen);
6243
6244 ptr = skb->data + offset;
6245 if (ptr >= srh_tlvs && ptr + len <= srh_end)
6246 srh_state->valid = false;
6247 else if (ptr < (void *)&srh->flags ||
6248 ptr + len > (void *)&srh->segments)
6249 return -EFAULT;
6250
6251 if (unlikely(bpf_try_make_writable(skb, offset + len)))
6252 return -EFAULT;
6253 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
6254 return -EINVAL;
6255 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6256
6257 memcpy(skb->data + offset, from, len);
6258 return 0;
6259 }
6260
6261 static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = {
6262 .func = bpf_lwt_seg6_store_bytes,
6263 .gpl_only = false,
6264 .ret_type = RET_INTEGER,
6265 .arg1_type = ARG_PTR_TO_CTX,
6266 .arg2_type = ARG_ANYTHING,
6267 .arg3_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6268 .arg4_type = ARG_CONST_SIZE
6269 };
6270
bpf_update_srh_state(struct sk_buff * skb)6271 static void bpf_update_srh_state(struct sk_buff *skb)
6272 {
6273 struct seg6_bpf_srh_state *srh_state =
6274 this_cpu_ptr(&seg6_bpf_srh_states);
6275 int srhoff = 0;
6276
6277 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) {
6278 srh_state->srh = NULL;
6279 } else {
6280 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6281 srh_state->hdrlen = srh_state->srh->hdrlen << 3;
6282 srh_state->valid = true;
6283 }
6284 }
6285
BPF_CALL_4(bpf_lwt_seg6_action,struct sk_buff *,skb,u32,action,void *,param,u32,param_len)6286 BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
6287 u32, action, void *, param, u32, param_len)
6288 {
6289 struct seg6_bpf_srh_state *srh_state =
6290 this_cpu_ptr(&seg6_bpf_srh_states);
6291 int hdroff = 0;
6292 int err;
6293
6294 switch (action) {
6295 case SEG6_LOCAL_ACTION_END_X:
6296 if (!seg6_bpf_has_valid_srh(skb))
6297 return -EBADMSG;
6298 if (param_len != sizeof(struct in6_addr))
6299 return -EINVAL;
6300 return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0);
6301 case SEG6_LOCAL_ACTION_END_T:
6302 if (!seg6_bpf_has_valid_srh(skb))
6303 return -EBADMSG;
6304 if (param_len != sizeof(int))
6305 return -EINVAL;
6306 return seg6_lookup_nexthop(skb, NULL, *(int *)param);
6307 case SEG6_LOCAL_ACTION_END_DT6:
6308 if (!seg6_bpf_has_valid_srh(skb))
6309 return -EBADMSG;
6310 if (param_len != sizeof(int))
6311 return -EINVAL;
6312
6313 if (ipv6_find_hdr(skb, &hdroff, IPPROTO_IPV6, NULL, NULL) < 0)
6314 return -EBADMSG;
6315 if (!pskb_pull(skb, hdroff))
6316 return -EBADMSG;
6317
6318 skb_postpull_rcsum(skb, skb_network_header(skb), hdroff);
6319 skb_reset_network_header(skb);
6320 skb_reset_transport_header(skb);
6321 skb->encapsulation = 0;
6322
6323 bpf_compute_data_pointers(skb);
6324 bpf_update_srh_state(skb);
6325 return seg6_lookup_nexthop(skb, NULL, *(int *)param);
6326 case SEG6_LOCAL_ACTION_END_B6:
6327 if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
6328 return -EBADMSG;
6329 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE,
6330 param, param_len);
6331 if (!err)
6332 bpf_update_srh_state(skb);
6333
6334 return err;
6335 case SEG6_LOCAL_ACTION_END_B6_ENCAP:
6336 if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
6337 return -EBADMSG;
6338 err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6,
6339 param, param_len);
6340 if (!err)
6341 bpf_update_srh_state(skb);
6342
6343 return err;
6344 default:
6345 return -EINVAL;
6346 }
6347 }
6348
6349 static const struct bpf_func_proto bpf_lwt_seg6_action_proto = {
6350 .func = bpf_lwt_seg6_action,
6351 .gpl_only = false,
6352 .ret_type = RET_INTEGER,
6353 .arg1_type = ARG_PTR_TO_CTX,
6354 .arg2_type = ARG_ANYTHING,
6355 .arg3_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6356 .arg4_type = ARG_CONST_SIZE
6357 };
6358
BPF_CALL_3(bpf_lwt_seg6_adjust_srh,struct sk_buff *,skb,u32,offset,s32,len)6359 BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
6360 s32, len)
6361 {
6362 struct seg6_bpf_srh_state *srh_state =
6363 this_cpu_ptr(&seg6_bpf_srh_states);
6364 struct ipv6_sr_hdr *srh = srh_state->srh;
6365 void *srh_end, *srh_tlvs, *ptr;
6366 struct ipv6hdr *hdr;
6367 int srhoff = 0;
6368 int ret;
6369
6370 if (unlikely(srh == NULL))
6371 return -EINVAL;
6372
6373 srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) +
6374 ((srh->first_segment + 1) << 4));
6375 srh_end = (void *)((unsigned char *)srh + sizeof(*srh) +
6376 srh_state->hdrlen);
6377 ptr = skb->data + offset;
6378
6379 if (unlikely(ptr < srh_tlvs || ptr > srh_end))
6380 return -EFAULT;
6381 if (unlikely(len < 0 && (void *)((char *)ptr - len) > srh_end))
6382 return -EFAULT;
6383
6384 if (len > 0) {
6385 ret = skb_cow_head(skb, len);
6386 if (unlikely(ret < 0))
6387 return ret;
6388
6389 ret = bpf_skb_net_hdr_push(skb, offset, len);
6390 } else {
6391 ret = bpf_skb_net_hdr_pop(skb, offset, -1 * len);
6392 }
6393
6394 bpf_compute_data_pointers(skb);
6395 if (unlikely(ret < 0))
6396 return ret;
6397
6398 hdr = (struct ipv6hdr *)skb->data;
6399 hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
6400
6401 if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
6402 return -EINVAL;
6403 srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
6404 srh_state->hdrlen += len;
6405 srh_state->valid = false;
6406 return 0;
6407 }
6408
6409 static const struct bpf_func_proto bpf_lwt_seg6_adjust_srh_proto = {
6410 .func = bpf_lwt_seg6_adjust_srh,
6411 .gpl_only = false,
6412 .ret_type = RET_INTEGER,
6413 .arg1_type = ARG_PTR_TO_CTX,
6414 .arg2_type = ARG_ANYTHING,
6415 .arg3_type = ARG_ANYTHING,
6416 };
6417 #endif /* CONFIG_IPV6_SEG6_BPF */
6418
6419 #ifdef CONFIG_INET
sk_lookup(struct net * net,struct bpf_sock_tuple * tuple,int dif,int sdif,u8 family,u8 proto)6420 static struct sock *sk_lookup(struct net *net, struct bpf_sock_tuple *tuple,
6421 int dif, int sdif, u8 family, u8 proto)
6422 {
6423 bool refcounted = false;
6424 struct sock *sk = NULL;
6425
6426 if (family == AF_INET) {
6427 __be32 src4 = tuple->ipv4.saddr;
6428 __be32 dst4 = tuple->ipv4.daddr;
6429
6430 if (proto == IPPROTO_TCP)
6431 sk = __inet_lookup(net, &tcp_hashinfo, NULL, 0,
6432 src4, tuple->ipv4.sport,
6433 dst4, tuple->ipv4.dport,
6434 dif, sdif, &refcounted);
6435 else
6436 sk = __udp4_lib_lookup(net, src4, tuple->ipv4.sport,
6437 dst4, tuple->ipv4.dport,
6438 dif, sdif, &udp_table, NULL);
6439 #if IS_ENABLED(CONFIG_IPV6)
6440 } else {
6441 struct in6_addr *src6 = (struct in6_addr *)&tuple->ipv6.saddr;
6442 struct in6_addr *dst6 = (struct in6_addr *)&tuple->ipv6.daddr;
6443
6444 if (proto == IPPROTO_TCP)
6445 sk = __inet6_lookup(net, &tcp_hashinfo, NULL, 0,
6446 src6, tuple->ipv6.sport,
6447 dst6, ntohs(tuple->ipv6.dport),
6448 dif, sdif, &refcounted);
6449 else if (likely(ipv6_bpf_stub))
6450 sk = ipv6_bpf_stub->udp6_lib_lookup(net,
6451 src6, tuple->ipv6.sport,
6452 dst6, tuple->ipv6.dport,
6453 dif, sdif,
6454 &udp_table, NULL);
6455 #endif
6456 }
6457
6458 if (unlikely(sk && !refcounted && !sock_flag(sk, SOCK_RCU_FREE))) {
6459 WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6460 sk = NULL;
6461 }
6462 return sk;
6463 }
6464
6465 /* bpf_skc_lookup performs the core lookup for different types of sockets,
6466 * taking a reference on the socket if it doesn't have the flag SOCK_RCU_FREE.
6467 * Returns the socket as an 'unsigned long' to simplify the casting in the
6468 * callers to satisfy BPF_CALL declarations.
6469 */
6470 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)6471 __bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6472 struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
6473 u64 flags)
6474 {
6475 struct sock *sk = NULL;
6476 u8 family = AF_UNSPEC;
6477 struct net *net;
6478 int sdif;
6479
6480 if (len == sizeof(tuple->ipv4))
6481 family = AF_INET;
6482 else if (len == sizeof(tuple->ipv6))
6483 family = AF_INET6;
6484 else
6485 return NULL;
6486
6487 if (unlikely(family == AF_UNSPEC || flags ||
6488 !((s32)netns_id < 0 || netns_id <= S32_MAX)))
6489 goto out;
6490
6491 if (family == AF_INET)
6492 sdif = inet_sdif(skb);
6493 else
6494 sdif = inet6_sdif(skb);
6495
6496 if ((s32)netns_id < 0) {
6497 net = caller_net;
6498 sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
6499 } else {
6500 net = get_net_ns_by_id(caller_net, netns_id);
6501 if (unlikely(!net))
6502 goto out;
6503 sk = sk_lookup(net, tuple, ifindex, sdif, family, proto);
6504 put_net(net);
6505 }
6506
6507 out:
6508 return sk;
6509 }
6510
6511 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)6512 __bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6513 struct net *caller_net, u32 ifindex, u8 proto, u64 netns_id,
6514 u64 flags)
6515 {
6516 struct sock *sk = __bpf_skc_lookup(skb, tuple, len, caller_net,
6517 ifindex, proto, netns_id, flags);
6518
6519 if (sk) {
6520 struct sock *sk2 = sk_to_full_sk(sk);
6521
6522 /* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
6523 * sock refcnt is decremented to prevent a request_sock leak.
6524 */
6525 if (!sk_fullsock(sk2))
6526 sk2 = NULL;
6527 if (sk2 != sk) {
6528 sock_gen_put(sk);
6529 /* Ensure there is no need to bump sk2 refcnt */
6530 if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
6531 WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6532 return NULL;
6533 }
6534 sk = sk2;
6535 }
6536 }
6537
6538 return sk;
6539 }
6540
6541 static struct sock *
bpf_skc_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)6542 bpf_skc_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6543 u8 proto, u64 netns_id, u64 flags)
6544 {
6545 struct net *caller_net;
6546 int ifindex;
6547
6548 if (skb->dev) {
6549 caller_net = dev_net(skb->dev);
6550 ifindex = skb->dev->ifindex;
6551 } else {
6552 caller_net = sock_net(skb->sk);
6553 ifindex = 0;
6554 }
6555
6556 return __bpf_skc_lookup(skb, tuple, len, caller_net, ifindex, proto,
6557 netns_id, flags);
6558 }
6559
6560 static struct sock *
bpf_sk_lookup(struct sk_buff * skb,struct bpf_sock_tuple * tuple,u32 len,u8 proto,u64 netns_id,u64 flags)6561 bpf_sk_lookup(struct sk_buff *skb, struct bpf_sock_tuple *tuple, u32 len,
6562 u8 proto, u64 netns_id, u64 flags)
6563 {
6564 struct sock *sk = bpf_skc_lookup(skb, tuple, len, proto, netns_id,
6565 flags);
6566
6567 if (sk) {
6568 struct sock *sk2 = sk_to_full_sk(sk);
6569
6570 /* sk_to_full_sk() may return (sk)->rsk_listener, so make sure the original sk
6571 * sock refcnt is decremented to prevent a request_sock leak.
6572 */
6573 if (!sk_fullsock(sk2))
6574 sk2 = NULL;
6575 if (sk2 != sk) {
6576 sock_gen_put(sk);
6577 /* Ensure there is no need to bump sk2 refcnt */
6578 if (unlikely(sk2 && !sock_flag(sk2, SOCK_RCU_FREE))) {
6579 WARN_ONCE(1, "Found non-RCU, unreferenced socket!");
6580 return NULL;
6581 }
6582 sk = sk2;
6583 }
6584 }
6585
6586 return sk;
6587 }
6588
BPF_CALL_5(bpf_skc_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6589 BPF_CALL_5(bpf_skc_lookup_tcp, struct sk_buff *, skb,
6590 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6591 {
6592 return (unsigned long)bpf_skc_lookup(skb, tuple, len, IPPROTO_TCP,
6593 netns_id, flags);
6594 }
6595
6596 static const struct bpf_func_proto bpf_skc_lookup_tcp_proto = {
6597 .func = bpf_skc_lookup_tcp,
6598 .gpl_only = false,
6599 .pkt_access = true,
6600 .ret_type = RET_PTR_TO_SOCK_COMMON_OR_NULL,
6601 .arg1_type = ARG_PTR_TO_CTX,
6602 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6603 .arg3_type = ARG_CONST_SIZE,
6604 .arg4_type = ARG_ANYTHING,
6605 .arg5_type = ARG_ANYTHING,
6606 };
6607
BPF_CALL_5(bpf_sk_lookup_tcp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6608 BPF_CALL_5(bpf_sk_lookup_tcp, struct sk_buff *, skb,
6609 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6610 {
6611 return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_TCP,
6612 netns_id, flags);
6613 }
6614
6615 static const struct bpf_func_proto bpf_sk_lookup_tcp_proto = {
6616 .func = bpf_sk_lookup_tcp,
6617 .gpl_only = false,
6618 .pkt_access = true,
6619 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6620 .arg1_type = ARG_PTR_TO_CTX,
6621 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6622 .arg3_type = ARG_CONST_SIZE,
6623 .arg4_type = ARG_ANYTHING,
6624 .arg5_type = ARG_ANYTHING,
6625 };
6626
BPF_CALL_5(bpf_sk_lookup_udp,struct sk_buff *,skb,struct bpf_sock_tuple *,tuple,u32,len,u64,netns_id,u64,flags)6627 BPF_CALL_5(bpf_sk_lookup_udp, struct sk_buff *, skb,
6628 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6629 {
6630 return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_UDP,
6631 netns_id, flags);
6632 }
6633
6634 static const struct bpf_func_proto bpf_sk_lookup_udp_proto = {
6635 .func = bpf_sk_lookup_udp,
6636 .gpl_only = false,
6637 .pkt_access = true,
6638 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6639 .arg1_type = ARG_PTR_TO_CTX,
6640 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6641 .arg3_type = ARG_CONST_SIZE,
6642 .arg4_type = ARG_ANYTHING,
6643 .arg5_type = ARG_ANYTHING,
6644 };
6645
BPF_CALL_1(bpf_sk_release,struct sock *,sk)6646 BPF_CALL_1(bpf_sk_release, struct sock *, sk)
6647 {
6648 if (sk && sk_is_refcounted(sk))
6649 sock_gen_put(sk);
6650 return 0;
6651 }
6652
6653 static const struct bpf_func_proto bpf_sk_release_proto = {
6654 .func = bpf_sk_release,
6655 .gpl_only = false,
6656 .ret_type = RET_INTEGER,
6657 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON | OBJ_RELEASE,
6658 };
6659
BPF_CALL_5(bpf_xdp_sk_lookup_udp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6660 BPF_CALL_5(bpf_xdp_sk_lookup_udp, struct xdp_buff *, ctx,
6661 struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6662 {
6663 struct net *caller_net = dev_net(ctx->rxq->dev);
6664 int ifindex = ctx->rxq->dev->ifindex;
6665
6666 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
6667 ifindex, IPPROTO_UDP, netns_id,
6668 flags);
6669 }
6670
6671 static const struct bpf_func_proto bpf_xdp_sk_lookup_udp_proto = {
6672 .func = bpf_xdp_sk_lookup_udp,
6673 .gpl_only = false,
6674 .pkt_access = true,
6675 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6676 .arg1_type = ARG_PTR_TO_CTX,
6677 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6678 .arg3_type = ARG_CONST_SIZE,
6679 .arg4_type = ARG_ANYTHING,
6680 .arg5_type = ARG_ANYTHING,
6681 };
6682
BPF_CALL_5(bpf_xdp_skc_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6683 BPF_CALL_5(bpf_xdp_skc_lookup_tcp, struct xdp_buff *, ctx,
6684 struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6685 {
6686 struct net *caller_net = dev_net(ctx->rxq->dev);
6687 int ifindex = ctx->rxq->dev->ifindex;
6688
6689 return (unsigned long)__bpf_skc_lookup(NULL, tuple, len, caller_net,
6690 ifindex, IPPROTO_TCP, netns_id,
6691 flags);
6692 }
6693
6694 static const struct bpf_func_proto bpf_xdp_skc_lookup_tcp_proto = {
6695 .func = bpf_xdp_skc_lookup_tcp,
6696 .gpl_only = false,
6697 .pkt_access = true,
6698 .ret_type = RET_PTR_TO_SOCK_COMMON_OR_NULL,
6699 .arg1_type = ARG_PTR_TO_CTX,
6700 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6701 .arg3_type = ARG_CONST_SIZE,
6702 .arg4_type = ARG_ANYTHING,
6703 .arg5_type = ARG_ANYTHING,
6704 };
6705
BPF_CALL_5(bpf_xdp_sk_lookup_tcp,struct xdp_buff *,ctx,struct bpf_sock_tuple *,tuple,u32,len,u32,netns_id,u64,flags)6706 BPF_CALL_5(bpf_xdp_sk_lookup_tcp, struct xdp_buff *, ctx,
6707 struct bpf_sock_tuple *, tuple, u32, len, u32, netns_id, u64, flags)
6708 {
6709 struct net *caller_net = dev_net(ctx->rxq->dev);
6710 int ifindex = ctx->rxq->dev->ifindex;
6711
6712 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len, caller_net,
6713 ifindex, IPPROTO_TCP, netns_id,
6714 flags);
6715 }
6716
6717 static const struct bpf_func_proto bpf_xdp_sk_lookup_tcp_proto = {
6718 .func = bpf_xdp_sk_lookup_tcp,
6719 .gpl_only = false,
6720 .pkt_access = true,
6721 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6722 .arg1_type = ARG_PTR_TO_CTX,
6723 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6724 .arg3_type = ARG_CONST_SIZE,
6725 .arg4_type = ARG_ANYTHING,
6726 .arg5_type = ARG_ANYTHING,
6727 };
6728
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)6729 BPF_CALL_5(bpf_sock_addr_skc_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
6730 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6731 {
6732 return (unsigned long)__bpf_skc_lookup(NULL, tuple, len,
6733 sock_net(ctx->sk), 0,
6734 IPPROTO_TCP, netns_id, flags);
6735 }
6736
6737 static const struct bpf_func_proto bpf_sock_addr_skc_lookup_tcp_proto = {
6738 .func = bpf_sock_addr_skc_lookup_tcp,
6739 .gpl_only = false,
6740 .ret_type = RET_PTR_TO_SOCK_COMMON_OR_NULL,
6741 .arg1_type = ARG_PTR_TO_CTX,
6742 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6743 .arg3_type = ARG_CONST_SIZE,
6744 .arg4_type = ARG_ANYTHING,
6745 .arg5_type = ARG_ANYTHING,
6746 };
6747
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)6748 BPF_CALL_5(bpf_sock_addr_sk_lookup_tcp, struct bpf_sock_addr_kern *, ctx,
6749 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6750 {
6751 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
6752 sock_net(ctx->sk), 0, IPPROTO_TCP,
6753 netns_id, flags);
6754 }
6755
6756 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_tcp_proto = {
6757 .func = bpf_sock_addr_sk_lookup_tcp,
6758 .gpl_only = false,
6759 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6760 .arg1_type = ARG_PTR_TO_CTX,
6761 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6762 .arg3_type = ARG_CONST_SIZE,
6763 .arg4_type = ARG_ANYTHING,
6764 .arg5_type = ARG_ANYTHING,
6765 };
6766
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)6767 BPF_CALL_5(bpf_sock_addr_sk_lookup_udp, struct bpf_sock_addr_kern *, ctx,
6768 struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
6769 {
6770 return (unsigned long)__bpf_sk_lookup(NULL, tuple, len,
6771 sock_net(ctx->sk), 0, IPPROTO_UDP,
6772 netns_id, flags);
6773 }
6774
6775 static const struct bpf_func_proto bpf_sock_addr_sk_lookup_udp_proto = {
6776 .func = bpf_sock_addr_sk_lookup_udp,
6777 .gpl_only = false,
6778 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6779 .arg1_type = ARG_PTR_TO_CTX,
6780 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6781 .arg3_type = ARG_CONST_SIZE,
6782 .arg4_type = ARG_ANYTHING,
6783 .arg5_type = ARG_ANYTHING,
6784 };
6785
bpf_tcp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)6786 bool bpf_tcp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
6787 struct bpf_insn_access_aux *info)
6788 {
6789 if (off < 0 || off >= offsetofend(struct bpf_tcp_sock,
6790 icsk_retransmits))
6791 return false;
6792
6793 if (off % size != 0)
6794 return false;
6795
6796 switch (off) {
6797 case offsetof(struct bpf_tcp_sock, bytes_received):
6798 case offsetof(struct bpf_tcp_sock, bytes_acked):
6799 return size == sizeof(__u64);
6800 default:
6801 return size == sizeof(__u32);
6802 }
6803 }
6804
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)6805 u32 bpf_tcp_sock_convert_ctx_access(enum bpf_access_type type,
6806 const struct bpf_insn *si,
6807 struct bpf_insn *insn_buf,
6808 struct bpf_prog *prog, u32 *target_size)
6809 {
6810 struct bpf_insn *insn = insn_buf;
6811
6812 #define BPF_TCP_SOCK_GET_COMMON(FIELD) \
6813 do { \
6814 BUILD_BUG_ON(sizeof_field(struct tcp_sock, FIELD) > \
6815 sizeof_field(struct bpf_tcp_sock, FIELD)); \
6816 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_sock, FIELD),\
6817 si->dst_reg, si->src_reg, \
6818 offsetof(struct tcp_sock, FIELD)); \
6819 } while (0)
6820
6821 #define BPF_INET_SOCK_GET_COMMON(FIELD) \
6822 do { \
6823 BUILD_BUG_ON(sizeof_field(struct inet_connection_sock, \
6824 FIELD) > \
6825 sizeof_field(struct bpf_tcp_sock, FIELD)); \
6826 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
6827 struct inet_connection_sock, \
6828 FIELD), \
6829 si->dst_reg, si->src_reg, \
6830 offsetof( \
6831 struct inet_connection_sock, \
6832 FIELD)); \
6833 } while (0)
6834
6835 if (insn > insn_buf)
6836 return insn - insn_buf;
6837
6838 switch (si->off) {
6839 case offsetof(struct bpf_tcp_sock, rtt_min):
6840 BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
6841 sizeof(struct minmax));
6842 BUILD_BUG_ON(sizeof(struct minmax) <
6843 sizeof(struct minmax_sample));
6844
6845 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
6846 offsetof(struct tcp_sock, rtt_min) +
6847 offsetof(struct minmax_sample, v));
6848 break;
6849 case offsetof(struct bpf_tcp_sock, snd_cwnd):
6850 BPF_TCP_SOCK_GET_COMMON(snd_cwnd);
6851 break;
6852 case offsetof(struct bpf_tcp_sock, srtt_us):
6853 BPF_TCP_SOCK_GET_COMMON(srtt_us);
6854 break;
6855 case offsetof(struct bpf_tcp_sock, snd_ssthresh):
6856 BPF_TCP_SOCK_GET_COMMON(snd_ssthresh);
6857 break;
6858 case offsetof(struct bpf_tcp_sock, rcv_nxt):
6859 BPF_TCP_SOCK_GET_COMMON(rcv_nxt);
6860 break;
6861 case offsetof(struct bpf_tcp_sock, snd_nxt):
6862 BPF_TCP_SOCK_GET_COMMON(snd_nxt);
6863 break;
6864 case offsetof(struct bpf_tcp_sock, snd_una):
6865 BPF_TCP_SOCK_GET_COMMON(snd_una);
6866 break;
6867 case offsetof(struct bpf_tcp_sock, mss_cache):
6868 BPF_TCP_SOCK_GET_COMMON(mss_cache);
6869 break;
6870 case offsetof(struct bpf_tcp_sock, ecn_flags):
6871 BPF_TCP_SOCK_GET_COMMON(ecn_flags);
6872 break;
6873 case offsetof(struct bpf_tcp_sock, rate_delivered):
6874 BPF_TCP_SOCK_GET_COMMON(rate_delivered);
6875 break;
6876 case offsetof(struct bpf_tcp_sock, rate_interval_us):
6877 BPF_TCP_SOCK_GET_COMMON(rate_interval_us);
6878 break;
6879 case offsetof(struct bpf_tcp_sock, packets_out):
6880 BPF_TCP_SOCK_GET_COMMON(packets_out);
6881 break;
6882 case offsetof(struct bpf_tcp_sock, retrans_out):
6883 BPF_TCP_SOCK_GET_COMMON(retrans_out);
6884 break;
6885 case offsetof(struct bpf_tcp_sock, total_retrans):
6886 BPF_TCP_SOCK_GET_COMMON(total_retrans);
6887 break;
6888 case offsetof(struct bpf_tcp_sock, segs_in):
6889 BPF_TCP_SOCK_GET_COMMON(segs_in);
6890 break;
6891 case offsetof(struct bpf_tcp_sock, data_segs_in):
6892 BPF_TCP_SOCK_GET_COMMON(data_segs_in);
6893 break;
6894 case offsetof(struct bpf_tcp_sock, segs_out):
6895 BPF_TCP_SOCK_GET_COMMON(segs_out);
6896 break;
6897 case offsetof(struct bpf_tcp_sock, data_segs_out):
6898 BPF_TCP_SOCK_GET_COMMON(data_segs_out);
6899 break;
6900 case offsetof(struct bpf_tcp_sock, lost_out):
6901 BPF_TCP_SOCK_GET_COMMON(lost_out);
6902 break;
6903 case offsetof(struct bpf_tcp_sock, sacked_out):
6904 BPF_TCP_SOCK_GET_COMMON(sacked_out);
6905 break;
6906 case offsetof(struct bpf_tcp_sock, bytes_received):
6907 BPF_TCP_SOCK_GET_COMMON(bytes_received);
6908 break;
6909 case offsetof(struct bpf_tcp_sock, bytes_acked):
6910 BPF_TCP_SOCK_GET_COMMON(bytes_acked);
6911 break;
6912 case offsetof(struct bpf_tcp_sock, dsack_dups):
6913 BPF_TCP_SOCK_GET_COMMON(dsack_dups);
6914 break;
6915 case offsetof(struct bpf_tcp_sock, delivered):
6916 BPF_TCP_SOCK_GET_COMMON(delivered);
6917 break;
6918 case offsetof(struct bpf_tcp_sock, delivered_ce):
6919 BPF_TCP_SOCK_GET_COMMON(delivered_ce);
6920 break;
6921 case offsetof(struct bpf_tcp_sock, icsk_retransmits):
6922 BPF_INET_SOCK_GET_COMMON(icsk_retransmits);
6923 break;
6924 }
6925
6926 return insn - insn_buf;
6927 }
6928
BPF_CALL_1(bpf_tcp_sock,struct sock *,sk)6929 BPF_CALL_1(bpf_tcp_sock, struct sock *, sk)
6930 {
6931 if (sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
6932 return (unsigned long)sk;
6933
6934 return (unsigned long)NULL;
6935 }
6936
6937 const struct bpf_func_proto bpf_tcp_sock_proto = {
6938 .func = bpf_tcp_sock,
6939 .gpl_only = false,
6940 .ret_type = RET_PTR_TO_TCP_SOCK_OR_NULL,
6941 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
6942 };
6943
BPF_CALL_1(bpf_get_listener_sock,struct sock *,sk)6944 BPF_CALL_1(bpf_get_listener_sock, struct sock *, sk)
6945 {
6946 sk = sk_to_full_sk(sk);
6947
6948 if (sk->sk_state == TCP_LISTEN && sock_flag(sk, SOCK_RCU_FREE))
6949 return (unsigned long)sk;
6950
6951 return (unsigned long)NULL;
6952 }
6953
6954 static const struct bpf_func_proto bpf_get_listener_sock_proto = {
6955 .func = bpf_get_listener_sock,
6956 .gpl_only = false,
6957 .ret_type = RET_PTR_TO_SOCKET_OR_NULL,
6958 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
6959 };
6960
BPF_CALL_1(bpf_skb_ecn_set_ce,struct sk_buff *,skb)6961 BPF_CALL_1(bpf_skb_ecn_set_ce, struct sk_buff *, skb)
6962 {
6963 unsigned int iphdr_len;
6964
6965 switch (skb_protocol(skb, true)) {
6966 case cpu_to_be16(ETH_P_IP):
6967 iphdr_len = sizeof(struct iphdr);
6968 break;
6969 case cpu_to_be16(ETH_P_IPV6):
6970 iphdr_len = sizeof(struct ipv6hdr);
6971 break;
6972 default:
6973 return 0;
6974 }
6975
6976 if (skb_headlen(skb) < iphdr_len)
6977 return 0;
6978
6979 if (skb_cloned(skb) && !skb_clone_writable(skb, iphdr_len))
6980 return 0;
6981
6982 return INET_ECN_set_ce(skb);
6983 }
6984
bpf_xdp_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)6985 bool bpf_xdp_sock_is_valid_access(int off, int size, enum bpf_access_type type,
6986 struct bpf_insn_access_aux *info)
6987 {
6988 if (off < 0 || off >= offsetofend(struct bpf_xdp_sock, queue_id))
6989 return false;
6990
6991 if (off % size != 0)
6992 return false;
6993
6994 switch (off) {
6995 default:
6996 return size == sizeof(__u32);
6997 }
6998 }
6999
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)7000 u32 bpf_xdp_sock_convert_ctx_access(enum bpf_access_type type,
7001 const struct bpf_insn *si,
7002 struct bpf_insn *insn_buf,
7003 struct bpf_prog *prog, u32 *target_size)
7004 {
7005 struct bpf_insn *insn = insn_buf;
7006
7007 #define BPF_XDP_SOCK_GET(FIELD) \
7008 do { \
7009 BUILD_BUG_ON(sizeof_field(struct xdp_sock, FIELD) > \
7010 sizeof_field(struct bpf_xdp_sock, FIELD)); \
7011 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_sock, FIELD),\
7012 si->dst_reg, si->src_reg, \
7013 offsetof(struct xdp_sock, FIELD)); \
7014 } while (0)
7015
7016 switch (si->off) {
7017 case offsetof(struct bpf_xdp_sock, queue_id):
7018 BPF_XDP_SOCK_GET(queue_id);
7019 break;
7020 }
7021
7022 return insn - insn_buf;
7023 }
7024
7025 static const struct bpf_func_proto bpf_skb_ecn_set_ce_proto = {
7026 .func = bpf_skb_ecn_set_ce,
7027 .gpl_only = false,
7028 .ret_type = RET_INTEGER,
7029 .arg1_type = ARG_PTR_TO_CTX,
7030 };
7031
BPF_CALL_5(bpf_tcp_check_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)7032 BPF_CALL_5(bpf_tcp_check_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
7033 struct tcphdr *, th, u32, th_len)
7034 {
7035 #ifdef CONFIG_SYN_COOKIES
7036 u32 cookie;
7037 int ret;
7038
7039 if (unlikely(!sk || th_len < sizeof(*th)))
7040 return -EINVAL;
7041
7042 /* sk_listener() allows TCP_NEW_SYN_RECV, which makes no sense here. */
7043 if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
7044 return -EINVAL;
7045
7046 if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
7047 return -EINVAL;
7048
7049 if (!th->ack || th->rst || th->syn)
7050 return -ENOENT;
7051
7052 if (unlikely(iph_len < sizeof(struct iphdr)))
7053 return -EINVAL;
7054
7055 if (tcp_synq_no_recent_overflow(sk))
7056 return -ENOENT;
7057
7058 cookie = ntohl(th->ack_seq) - 1;
7059
7060 /* Both struct iphdr and struct ipv6hdr have the version field at the
7061 * same offset so we can cast to the shorter header (struct iphdr).
7062 */
7063 switch (((struct iphdr *)iph)->version) {
7064 case 4:
7065 if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
7066 return -EINVAL;
7067
7068 ret = __cookie_v4_check((struct iphdr *)iph, th, cookie);
7069 break;
7070
7071 #if IS_BUILTIN(CONFIG_IPV6)
7072 case 6:
7073 if (unlikely(iph_len < sizeof(struct ipv6hdr)))
7074 return -EINVAL;
7075
7076 if (sk->sk_family != AF_INET6)
7077 return -EINVAL;
7078
7079 ret = __cookie_v6_check((struct ipv6hdr *)iph, th, cookie);
7080 break;
7081 #endif /* CONFIG_IPV6 */
7082
7083 default:
7084 return -EPROTONOSUPPORT;
7085 }
7086
7087 if (ret > 0)
7088 return 0;
7089
7090 return -ENOENT;
7091 #else
7092 return -ENOTSUPP;
7093 #endif
7094 }
7095
7096 static const struct bpf_func_proto bpf_tcp_check_syncookie_proto = {
7097 .func = bpf_tcp_check_syncookie,
7098 .gpl_only = true,
7099 .pkt_access = true,
7100 .ret_type = RET_INTEGER,
7101 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7102 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
7103 .arg3_type = ARG_CONST_SIZE,
7104 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
7105 .arg5_type = ARG_CONST_SIZE,
7106 };
7107
BPF_CALL_5(bpf_tcp_gen_syncookie,struct sock *,sk,void *,iph,u32,iph_len,struct tcphdr *,th,u32,th_len)7108 BPF_CALL_5(bpf_tcp_gen_syncookie, struct sock *, sk, void *, iph, u32, iph_len,
7109 struct tcphdr *, th, u32, th_len)
7110 {
7111 #ifdef CONFIG_SYN_COOKIES
7112 u32 cookie;
7113 u16 mss;
7114
7115 if (unlikely(!sk || th_len < sizeof(*th) || th_len != th->doff * 4))
7116 return -EINVAL;
7117
7118 if (sk->sk_protocol != IPPROTO_TCP || sk->sk_state != TCP_LISTEN)
7119 return -EINVAL;
7120
7121 if (!READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_syncookies))
7122 return -ENOENT;
7123
7124 if (!th->syn || th->ack || th->fin || th->rst)
7125 return -EINVAL;
7126
7127 if (unlikely(iph_len < sizeof(struct iphdr)))
7128 return -EINVAL;
7129
7130 /* Both struct iphdr and struct ipv6hdr have the version field at the
7131 * same offset so we can cast to the shorter header (struct iphdr).
7132 */
7133 switch (((struct iphdr *)iph)->version) {
7134 case 4:
7135 if (sk->sk_family == AF_INET6 && ipv6_only_sock(sk))
7136 return -EINVAL;
7137
7138 mss = tcp_v4_get_syncookie(sk, iph, th, &cookie);
7139 break;
7140
7141 #if IS_BUILTIN(CONFIG_IPV6)
7142 case 6:
7143 if (unlikely(iph_len < sizeof(struct ipv6hdr)))
7144 return -EINVAL;
7145
7146 if (sk->sk_family != AF_INET6)
7147 return -EINVAL;
7148
7149 mss = tcp_v6_get_syncookie(sk, iph, th, &cookie);
7150 break;
7151 #endif /* CONFIG_IPV6 */
7152
7153 default:
7154 return -EPROTONOSUPPORT;
7155 }
7156 if (mss == 0)
7157 return -ENOENT;
7158
7159 return cookie | ((u64)mss << 32);
7160 #else
7161 return -EOPNOTSUPP;
7162 #endif /* CONFIG_SYN_COOKIES */
7163 }
7164
7165 static const struct bpf_func_proto bpf_tcp_gen_syncookie_proto = {
7166 .func = bpf_tcp_gen_syncookie,
7167 .gpl_only = true, /* __cookie_v*_init_sequence() is GPL */
7168 .pkt_access = true,
7169 .ret_type = RET_INTEGER,
7170 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7171 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
7172 .arg3_type = ARG_CONST_SIZE,
7173 .arg4_type = ARG_PTR_TO_MEM | MEM_RDONLY,
7174 .arg5_type = ARG_CONST_SIZE,
7175 };
7176
BPF_CALL_3(bpf_sk_assign,struct sk_buff *,skb,struct sock *,sk,u64,flags)7177 BPF_CALL_3(bpf_sk_assign, struct sk_buff *, skb, struct sock *, sk, u64, flags)
7178 {
7179 if (!sk || flags != 0)
7180 return -EINVAL;
7181 if (!skb_at_tc_ingress(skb))
7182 return -EOPNOTSUPP;
7183 if (unlikely(dev_net(skb->dev) != sock_net(sk)))
7184 return -ENETUNREACH;
7185 if (unlikely(sk_fullsock(sk) && sk->sk_reuseport))
7186 return -ESOCKTNOSUPPORT;
7187 if (sk_is_refcounted(sk) &&
7188 unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
7189 return -ENOENT;
7190
7191 skb_orphan(skb);
7192 skb->sk = sk;
7193 skb->destructor = sock_pfree;
7194
7195 return 0;
7196 }
7197
7198 static const struct bpf_func_proto bpf_sk_assign_proto = {
7199 .func = bpf_sk_assign,
7200 .gpl_only = false,
7201 .ret_type = RET_INTEGER,
7202 .arg1_type = ARG_PTR_TO_CTX,
7203 .arg2_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
7204 .arg3_type = ARG_ANYTHING,
7205 };
7206
bpf_search_tcp_opt(const u8 * op,const u8 * opend,u8 search_kind,const u8 * magic,u8 magic_len,bool * eol)7207 static const u8 *bpf_search_tcp_opt(const u8 *op, const u8 *opend,
7208 u8 search_kind, const u8 *magic,
7209 u8 magic_len, bool *eol)
7210 {
7211 u8 kind, kind_len;
7212
7213 *eol = false;
7214
7215 while (op < opend) {
7216 kind = op[0];
7217
7218 if (kind == TCPOPT_EOL) {
7219 *eol = true;
7220 return ERR_PTR(-ENOMSG);
7221 } else if (kind == TCPOPT_NOP) {
7222 op++;
7223 continue;
7224 }
7225
7226 if (opend - op < 2 || opend - op < op[1] || op[1] < 2)
7227 /* Something is wrong in the received header.
7228 * Follow the TCP stack's tcp_parse_options()
7229 * and just bail here.
7230 */
7231 return ERR_PTR(-EFAULT);
7232
7233 kind_len = op[1];
7234 if (search_kind == kind) {
7235 if (!magic_len)
7236 return op;
7237
7238 if (magic_len > kind_len - 2)
7239 return ERR_PTR(-ENOMSG);
7240
7241 if (!memcmp(&op[2], magic, magic_len))
7242 return op;
7243 }
7244
7245 op += kind_len;
7246 }
7247
7248 return ERR_PTR(-ENOMSG);
7249 }
7250
BPF_CALL_4(bpf_sock_ops_load_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,void *,search_res,u32,len,u64,flags)7251 BPF_CALL_4(bpf_sock_ops_load_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7252 void *, search_res, u32, len, u64, flags)
7253 {
7254 bool eol, load_syn = flags & BPF_LOAD_HDR_OPT_TCP_SYN;
7255 const u8 *op, *opend, *magic, *search = search_res;
7256 u8 search_kind, search_len, copy_len, magic_len;
7257 int ret;
7258
7259 /* 2 byte is the minimal option len except TCPOPT_NOP and
7260 * TCPOPT_EOL which are useless for the bpf prog to learn
7261 * and this helper disallow loading them also.
7262 */
7263 if (len < 2 || flags & ~BPF_LOAD_HDR_OPT_TCP_SYN)
7264 return -EINVAL;
7265
7266 search_kind = search[0];
7267 search_len = search[1];
7268
7269 if (search_len > len || search_kind == TCPOPT_NOP ||
7270 search_kind == TCPOPT_EOL)
7271 return -EINVAL;
7272
7273 if (search_kind == TCPOPT_EXP || search_kind == 253) {
7274 /* 16 or 32 bit magic. +2 for kind and kind length */
7275 if (search_len != 4 && search_len != 6)
7276 return -EINVAL;
7277 magic = &search[2];
7278 magic_len = search_len - 2;
7279 } else {
7280 if (search_len)
7281 return -EINVAL;
7282 magic = NULL;
7283 magic_len = 0;
7284 }
7285
7286 if (load_syn) {
7287 ret = bpf_sock_ops_get_syn(bpf_sock, TCP_BPF_SYN, &op);
7288 if (ret < 0)
7289 return ret;
7290
7291 opend = op + ret;
7292 op += sizeof(struct tcphdr);
7293 } else {
7294 if (!bpf_sock->skb ||
7295 bpf_sock->op == BPF_SOCK_OPS_HDR_OPT_LEN_CB)
7296 /* This bpf_sock->op cannot call this helper */
7297 return -EPERM;
7298
7299 opend = bpf_sock->skb_data_end;
7300 op = bpf_sock->skb->data + sizeof(struct tcphdr);
7301 }
7302
7303 op = bpf_search_tcp_opt(op, opend, search_kind, magic, magic_len,
7304 &eol);
7305 if (IS_ERR(op))
7306 return PTR_ERR(op);
7307
7308 copy_len = op[1];
7309 ret = copy_len;
7310 if (copy_len > len) {
7311 ret = -ENOSPC;
7312 copy_len = len;
7313 }
7314
7315 memcpy(search_res, op, copy_len);
7316 return ret;
7317 }
7318
7319 static const struct bpf_func_proto bpf_sock_ops_load_hdr_opt_proto = {
7320 .func = bpf_sock_ops_load_hdr_opt,
7321 .gpl_only = false,
7322 .ret_type = RET_INTEGER,
7323 .arg1_type = ARG_PTR_TO_CTX,
7324 .arg2_type = ARG_PTR_TO_MEM,
7325 .arg3_type = ARG_CONST_SIZE,
7326 .arg4_type = ARG_ANYTHING,
7327 };
7328
BPF_CALL_4(bpf_sock_ops_store_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,const void *,from,u32,len,u64,flags)7329 BPF_CALL_4(bpf_sock_ops_store_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7330 const void *, from, u32, len, u64, flags)
7331 {
7332 u8 new_kind, new_kind_len, magic_len = 0, *opend;
7333 const u8 *op, *new_op, *magic = NULL;
7334 struct sk_buff *skb;
7335 bool eol;
7336
7337 if (bpf_sock->op != BPF_SOCK_OPS_WRITE_HDR_OPT_CB)
7338 return -EPERM;
7339
7340 if (len < 2 || flags)
7341 return -EINVAL;
7342
7343 new_op = from;
7344 new_kind = new_op[0];
7345 new_kind_len = new_op[1];
7346
7347 if (new_kind_len > len || new_kind == TCPOPT_NOP ||
7348 new_kind == TCPOPT_EOL)
7349 return -EINVAL;
7350
7351 if (new_kind_len > bpf_sock->remaining_opt_len)
7352 return -ENOSPC;
7353
7354 /* 253 is another experimental kind */
7355 if (new_kind == TCPOPT_EXP || new_kind == 253) {
7356 if (new_kind_len < 4)
7357 return -EINVAL;
7358 /* Match for the 2 byte magic also.
7359 * RFC 6994: the magic could be 2 or 4 bytes.
7360 * Hence, matching by 2 byte only is on the
7361 * conservative side but it is the right
7362 * thing to do for the 'search-for-duplication'
7363 * purpose.
7364 */
7365 magic = &new_op[2];
7366 magic_len = 2;
7367 }
7368
7369 /* Check for duplication */
7370 skb = bpf_sock->skb;
7371 op = skb->data + sizeof(struct tcphdr);
7372 opend = bpf_sock->skb_data_end;
7373
7374 op = bpf_search_tcp_opt(op, opend, new_kind, magic, magic_len,
7375 &eol);
7376 if (!IS_ERR(op))
7377 return -EEXIST;
7378
7379 if (PTR_ERR(op) != -ENOMSG)
7380 return PTR_ERR(op);
7381
7382 if (eol)
7383 /* The option has been ended. Treat it as no more
7384 * header option can be written.
7385 */
7386 return -ENOSPC;
7387
7388 /* No duplication found. Store the header option. */
7389 memcpy(opend, from, new_kind_len);
7390
7391 bpf_sock->remaining_opt_len -= new_kind_len;
7392 bpf_sock->skb_data_end += new_kind_len;
7393
7394 return 0;
7395 }
7396
7397 static const struct bpf_func_proto bpf_sock_ops_store_hdr_opt_proto = {
7398 .func = bpf_sock_ops_store_hdr_opt,
7399 .gpl_only = false,
7400 .ret_type = RET_INTEGER,
7401 .arg1_type = ARG_PTR_TO_CTX,
7402 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
7403 .arg3_type = ARG_CONST_SIZE,
7404 .arg4_type = ARG_ANYTHING,
7405 };
7406
BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt,struct bpf_sock_ops_kern *,bpf_sock,u32,len,u64,flags)7407 BPF_CALL_3(bpf_sock_ops_reserve_hdr_opt, struct bpf_sock_ops_kern *, bpf_sock,
7408 u32, len, u64, flags)
7409 {
7410 if (bpf_sock->op != BPF_SOCK_OPS_HDR_OPT_LEN_CB)
7411 return -EPERM;
7412
7413 if (flags || len < 2)
7414 return -EINVAL;
7415
7416 if (len > bpf_sock->remaining_opt_len)
7417 return -ENOSPC;
7418
7419 bpf_sock->remaining_opt_len -= len;
7420
7421 return 0;
7422 }
7423
7424 static const struct bpf_func_proto bpf_sock_ops_reserve_hdr_opt_proto = {
7425 .func = bpf_sock_ops_reserve_hdr_opt,
7426 .gpl_only = false,
7427 .ret_type = RET_INTEGER,
7428 .arg1_type = ARG_PTR_TO_CTX,
7429 .arg2_type = ARG_ANYTHING,
7430 .arg3_type = ARG_ANYTHING,
7431 };
7432
BPF_CALL_3(bpf_skb_set_tstamp,struct sk_buff *,skb,u64,tstamp,u32,tstamp_type)7433 BPF_CALL_3(bpf_skb_set_tstamp, struct sk_buff *, skb,
7434 u64, tstamp, u32, tstamp_type)
7435 {
7436 /* skb_clear_delivery_time() is done for inet protocol */
7437 if (skb->protocol != htons(ETH_P_IP) &&
7438 skb->protocol != htons(ETH_P_IPV6))
7439 return -EOPNOTSUPP;
7440
7441 switch (tstamp_type) {
7442 case BPF_SKB_TSTAMP_DELIVERY_MONO:
7443 if (!tstamp)
7444 return -EINVAL;
7445 skb->tstamp = tstamp;
7446 skb->mono_delivery_time = 1;
7447 break;
7448 case BPF_SKB_TSTAMP_UNSPEC:
7449 if (tstamp)
7450 return -EINVAL;
7451 skb->tstamp = 0;
7452 skb->mono_delivery_time = 0;
7453 break;
7454 default:
7455 return -EINVAL;
7456 }
7457
7458 return 0;
7459 }
7460
7461 static const struct bpf_func_proto bpf_skb_set_tstamp_proto = {
7462 .func = bpf_skb_set_tstamp,
7463 .gpl_only = false,
7464 .ret_type = RET_INTEGER,
7465 .arg1_type = ARG_PTR_TO_CTX,
7466 .arg2_type = ARG_ANYTHING,
7467 .arg3_type = ARG_ANYTHING,
7468 };
7469
7470 #endif /* CONFIG_INET */
7471
bpf_helper_changes_pkt_data(void * func)7472 bool bpf_helper_changes_pkt_data(void *func)
7473 {
7474 if (func == bpf_skb_vlan_push ||
7475 func == bpf_skb_vlan_pop ||
7476 func == bpf_skb_store_bytes ||
7477 func == bpf_skb_change_proto ||
7478 func == bpf_skb_change_head ||
7479 func == sk_skb_change_head ||
7480 func == bpf_skb_change_tail ||
7481 func == sk_skb_change_tail ||
7482 func == bpf_skb_adjust_room ||
7483 func == sk_skb_adjust_room ||
7484 func == bpf_skb_pull_data ||
7485 func == sk_skb_pull_data ||
7486 func == bpf_clone_redirect ||
7487 func == bpf_l3_csum_replace ||
7488 func == bpf_l4_csum_replace ||
7489 func == bpf_xdp_adjust_head ||
7490 func == bpf_xdp_adjust_meta ||
7491 func == bpf_msg_pull_data ||
7492 func == bpf_msg_push_data ||
7493 func == bpf_msg_pop_data ||
7494 func == bpf_xdp_adjust_tail ||
7495 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
7496 func == bpf_lwt_seg6_store_bytes ||
7497 func == bpf_lwt_seg6_adjust_srh ||
7498 func == bpf_lwt_seg6_action ||
7499 #endif
7500 #ifdef CONFIG_INET
7501 func == bpf_sock_ops_store_hdr_opt ||
7502 #endif
7503 func == bpf_lwt_in_push_encap ||
7504 func == bpf_lwt_xmit_push_encap)
7505 return true;
7506
7507 return false;
7508 }
7509
7510 const struct bpf_func_proto bpf_event_output_data_proto __weak;
7511 const struct bpf_func_proto bpf_sk_storage_get_cg_sock_proto __weak;
7512
7513 static const struct bpf_func_proto *
sock_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7514 sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7515 {
7516 switch (func_id) {
7517 /* inet and inet6 sockets are created in a process
7518 * context so there is always a valid uid/gid
7519 */
7520 case BPF_FUNC_get_current_uid_gid:
7521 return &bpf_get_current_uid_gid_proto;
7522 case BPF_FUNC_get_local_storage:
7523 return &bpf_get_local_storage_proto;
7524 case BPF_FUNC_get_socket_cookie:
7525 return &bpf_get_socket_cookie_sock_proto;
7526 case BPF_FUNC_get_netns_cookie:
7527 return &bpf_get_netns_cookie_sock_proto;
7528 case BPF_FUNC_perf_event_output:
7529 return &bpf_event_output_data_proto;
7530 case BPF_FUNC_get_current_pid_tgid:
7531 return &bpf_get_current_pid_tgid_proto;
7532 case BPF_FUNC_get_current_comm:
7533 return &bpf_get_current_comm_proto;
7534 #ifdef CONFIG_CGROUPS
7535 case BPF_FUNC_get_current_cgroup_id:
7536 return &bpf_get_current_cgroup_id_proto;
7537 case BPF_FUNC_get_current_ancestor_cgroup_id:
7538 return &bpf_get_current_ancestor_cgroup_id_proto;
7539 #endif
7540 #ifdef CONFIG_CGROUP_NET_CLASSID
7541 case BPF_FUNC_get_cgroup_classid:
7542 return &bpf_get_cgroup_classid_curr_proto;
7543 #endif
7544 case BPF_FUNC_sk_storage_get:
7545 return &bpf_sk_storage_get_cg_sock_proto;
7546 case BPF_FUNC_ktime_get_coarse_ns:
7547 return &bpf_ktime_get_coarse_ns_proto;
7548 default:
7549 return bpf_base_func_proto(func_id);
7550 }
7551 }
7552
7553 static const struct bpf_func_proto *
sock_addr_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7554 sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7555 {
7556 switch (func_id) {
7557 /* inet and inet6 sockets are created in a process
7558 * context so there is always a valid uid/gid
7559 */
7560 case BPF_FUNC_get_current_uid_gid:
7561 return &bpf_get_current_uid_gid_proto;
7562 case BPF_FUNC_bind:
7563 switch (prog->expected_attach_type) {
7564 case BPF_CGROUP_INET4_CONNECT:
7565 case BPF_CGROUP_INET6_CONNECT:
7566 return &bpf_bind_proto;
7567 default:
7568 return NULL;
7569 }
7570 case BPF_FUNC_get_socket_cookie:
7571 return &bpf_get_socket_cookie_sock_addr_proto;
7572 case BPF_FUNC_get_netns_cookie:
7573 return &bpf_get_netns_cookie_sock_addr_proto;
7574 case BPF_FUNC_get_local_storage:
7575 return &bpf_get_local_storage_proto;
7576 case BPF_FUNC_perf_event_output:
7577 return &bpf_event_output_data_proto;
7578 case BPF_FUNC_get_current_pid_tgid:
7579 return &bpf_get_current_pid_tgid_proto;
7580 case BPF_FUNC_get_current_comm:
7581 return &bpf_get_current_comm_proto;
7582 #ifdef CONFIG_CGROUPS
7583 case BPF_FUNC_get_current_cgroup_id:
7584 return &bpf_get_current_cgroup_id_proto;
7585 case BPF_FUNC_get_current_ancestor_cgroup_id:
7586 return &bpf_get_current_ancestor_cgroup_id_proto;
7587 #endif
7588 #ifdef CONFIG_CGROUP_NET_CLASSID
7589 case BPF_FUNC_get_cgroup_classid:
7590 return &bpf_get_cgroup_classid_curr_proto;
7591 #endif
7592 #ifdef CONFIG_INET
7593 case BPF_FUNC_sk_lookup_tcp:
7594 return &bpf_sock_addr_sk_lookup_tcp_proto;
7595 case BPF_FUNC_sk_lookup_udp:
7596 return &bpf_sock_addr_sk_lookup_udp_proto;
7597 case BPF_FUNC_sk_release:
7598 return &bpf_sk_release_proto;
7599 case BPF_FUNC_skc_lookup_tcp:
7600 return &bpf_sock_addr_skc_lookup_tcp_proto;
7601 #endif /* CONFIG_INET */
7602 case BPF_FUNC_sk_storage_get:
7603 return &bpf_sk_storage_get_proto;
7604 case BPF_FUNC_sk_storage_delete:
7605 return &bpf_sk_storage_delete_proto;
7606 case BPF_FUNC_setsockopt:
7607 switch (prog->expected_attach_type) {
7608 case BPF_CGROUP_INET4_BIND:
7609 case BPF_CGROUP_INET6_BIND:
7610 case BPF_CGROUP_INET4_CONNECT:
7611 case BPF_CGROUP_INET6_CONNECT:
7612 case BPF_CGROUP_UDP4_RECVMSG:
7613 case BPF_CGROUP_UDP6_RECVMSG:
7614 case BPF_CGROUP_UDP4_SENDMSG:
7615 case BPF_CGROUP_UDP6_SENDMSG:
7616 case BPF_CGROUP_INET4_GETPEERNAME:
7617 case BPF_CGROUP_INET6_GETPEERNAME:
7618 case BPF_CGROUP_INET4_GETSOCKNAME:
7619 case BPF_CGROUP_INET6_GETSOCKNAME:
7620 return &bpf_sock_addr_setsockopt_proto;
7621 default:
7622 return NULL;
7623 }
7624 case BPF_FUNC_getsockopt:
7625 switch (prog->expected_attach_type) {
7626 case BPF_CGROUP_INET4_BIND:
7627 case BPF_CGROUP_INET6_BIND:
7628 case BPF_CGROUP_INET4_CONNECT:
7629 case BPF_CGROUP_INET6_CONNECT:
7630 case BPF_CGROUP_UDP4_RECVMSG:
7631 case BPF_CGROUP_UDP6_RECVMSG:
7632 case BPF_CGROUP_UDP4_SENDMSG:
7633 case BPF_CGROUP_UDP6_SENDMSG:
7634 case BPF_CGROUP_INET4_GETPEERNAME:
7635 case BPF_CGROUP_INET6_GETPEERNAME:
7636 case BPF_CGROUP_INET4_GETSOCKNAME:
7637 case BPF_CGROUP_INET6_GETSOCKNAME:
7638 return &bpf_sock_addr_getsockopt_proto;
7639 default:
7640 return NULL;
7641 }
7642 default:
7643 return bpf_sk_base_func_proto(func_id);
7644 }
7645 }
7646
7647 static const struct bpf_func_proto *
sk_filter_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7648 sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7649 {
7650 switch (func_id) {
7651 case BPF_FUNC_skb_load_bytes:
7652 return &bpf_skb_load_bytes_proto;
7653 case BPF_FUNC_skb_load_bytes_relative:
7654 return &bpf_skb_load_bytes_relative_proto;
7655 case BPF_FUNC_get_socket_cookie:
7656 return &bpf_get_socket_cookie_proto;
7657 case BPF_FUNC_get_socket_uid:
7658 return &bpf_get_socket_uid_proto;
7659 case BPF_FUNC_perf_event_output:
7660 return &bpf_skb_event_output_proto;
7661 default:
7662 return bpf_sk_base_func_proto(func_id);
7663 }
7664 }
7665
7666 const struct bpf_func_proto bpf_sk_storage_get_proto __weak;
7667 const struct bpf_func_proto bpf_sk_storage_delete_proto __weak;
7668
7669 static const struct bpf_func_proto *
cg_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7670 cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7671 {
7672 switch (func_id) {
7673 case BPF_FUNC_get_local_storage:
7674 return &bpf_get_local_storage_proto;
7675 case BPF_FUNC_sk_fullsock:
7676 return &bpf_sk_fullsock_proto;
7677 case BPF_FUNC_sk_storage_get:
7678 return &bpf_sk_storage_get_proto;
7679 case BPF_FUNC_sk_storage_delete:
7680 return &bpf_sk_storage_delete_proto;
7681 case BPF_FUNC_perf_event_output:
7682 return &bpf_skb_event_output_proto;
7683 #ifdef CONFIG_SOCK_CGROUP_DATA
7684 case BPF_FUNC_skb_cgroup_id:
7685 return &bpf_skb_cgroup_id_proto;
7686 case BPF_FUNC_skb_ancestor_cgroup_id:
7687 return &bpf_skb_ancestor_cgroup_id_proto;
7688 case BPF_FUNC_sk_cgroup_id:
7689 return &bpf_sk_cgroup_id_proto;
7690 case BPF_FUNC_sk_ancestor_cgroup_id:
7691 return &bpf_sk_ancestor_cgroup_id_proto;
7692 #endif
7693 #ifdef CONFIG_INET
7694 case BPF_FUNC_sk_lookup_tcp:
7695 return &bpf_sk_lookup_tcp_proto;
7696 case BPF_FUNC_sk_lookup_udp:
7697 return &bpf_sk_lookup_udp_proto;
7698 case BPF_FUNC_sk_release:
7699 return &bpf_sk_release_proto;
7700 case BPF_FUNC_skc_lookup_tcp:
7701 return &bpf_skc_lookup_tcp_proto;
7702 case BPF_FUNC_tcp_sock:
7703 return &bpf_tcp_sock_proto;
7704 case BPF_FUNC_get_listener_sock:
7705 return &bpf_get_listener_sock_proto;
7706 case BPF_FUNC_skb_ecn_set_ce:
7707 return &bpf_skb_ecn_set_ce_proto;
7708 #endif
7709 default:
7710 return sk_filter_func_proto(func_id, prog);
7711 }
7712 }
7713
7714 static const struct bpf_func_proto *
tc_cls_act_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7715 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7716 {
7717 switch (func_id) {
7718 case BPF_FUNC_skb_store_bytes:
7719 return &bpf_skb_store_bytes_proto;
7720 case BPF_FUNC_skb_load_bytes:
7721 return &bpf_skb_load_bytes_proto;
7722 case BPF_FUNC_skb_load_bytes_relative:
7723 return &bpf_skb_load_bytes_relative_proto;
7724 case BPF_FUNC_skb_pull_data:
7725 return &bpf_skb_pull_data_proto;
7726 case BPF_FUNC_csum_diff:
7727 return &bpf_csum_diff_proto;
7728 case BPF_FUNC_csum_update:
7729 return &bpf_csum_update_proto;
7730 case BPF_FUNC_csum_level:
7731 return &bpf_csum_level_proto;
7732 case BPF_FUNC_l3_csum_replace:
7733 return &bpf_l3_csum_replace_proto;
7734 case BPF_FUNC_l4_csum_replace:
7735 return &bpf_l4_csum_replace_proto;
7736 case BPF_FUNC_clone_redirect:
7737 return &bpf_clone_redirect_proto;
7738 case BPF_FUNC_get_cgroup_classid:
7739 return &bpf_get_cgroup_classid_proto;
7740 case BPF_FUNC_skb_vlan_push:
7741 return &bpf_skb_vlan_push_proto;
7742 case BPF_FUNC_skb_vlan_pop:
7743 return &bpf_skb_vlan_pop_proto;
7744 case BPF_FUNC_skb_change_proto:
7745 return &bpf_skb_change_proto_proto;
7746 case BPF_FUNC_skb_change_type:
7747 return &bpf_skb_change_type_proto;
7748 case BPF_FUNC_skb_adjust_room:
7749 return &bpf_skb_adjust_room_proto;
7750 case BPF_FUNC_skb_change_tail:
7751 return &bpf_skb_change_tail_proto;
7752 case BPF_FUNC_skb_change_head:
7753 return &bpf_skb_change_head_proto;
7754 case BPF_FUNC_skb_get_tunnel_key:
7755 return &bpf_skb_get_tunnel_key_proto;
7756 case BPF_FUNC_skb_set_tunnel_key:
7757 return bpf_get_skb_set_tunnel_proto(func_id);
7758 case BPF_FUNC_skb_get_tunnel_opt:
7759 return &bpf_skb_get_tunnel_opt_proto;
7760 case BPF_FUNC_skb_set_tunnel_opt:
7761 return bpf_get_skb_set_tunnel_proto(func_id);
7762 case BPF_FUNC_redirect:
7763 return &bpf_redirect_proto;
7764 case BPF_FUNC_redirect_neigh:
7765 return &bpf_redirect_neigh_proto;
7766 case BPF_FUNC_redirect_peer:
7767 return &bpf_redirect_peer_proto;
7768 case BPF_FUNC_get_route_realm:
7769 return &bpf_get_route_realm_proto;
7770 case BPF_FUNC_get_hash_recalc:
7771 return &bpf_get_hash_recalc_proto;
7772 case BPF_FUNC_set_hash_invalid:
7773 return &bpf_set_hash_invalid_proto;
7774 case BPF_FUNC_set_hash:
7775 return &bpf_set_hash_proto;
7776 case BPF_FUNC_perf_event_output:
7777 return &bpf_skb_event_output_proto;
7778 case BPF_FUNC_get_smp_processor_id:
7779 return &bpf_get_smp_processor_id_proto;
7780 case BPF_FUNC_skb_under_cgroup:
7781 return &bpf_skb_under_cgroup_proto;
7782 case BPF_FUNC_get_socket_cookie:
7783 return &bpf_get_socket_cookie_proto;
7784 case BPF_FUNC_get_socket_uid:
7785 return &bpf_get_socket_uid_proto;
7786 case BPF_FUNC_fib_lookup:
7787 return &bpf_skb_fib_lookup_proto;
7788 case BPF_FUNC_check_mtu:
7789 return &bpf_skb_check_mtu_proto;
7790 case BPF_FUNC_sk_fullsock:
7791 return &bpf_sk_fullsock_proto;
7792 case BPF_FUNC_sk_storage_get:
7793 return &bpf_sk_storage_get_proto;
7794 case BPF_FUNC_sk_storage_delete:
7795 return &bpf_sk_storage_delete_proto;
7796 #ifdef CONFIG_XFRM
7797 case BPF_FUNC_skb_get_xfrm_state:
7798 return &bpf_skb_get_xfrm_state_proto;
7799 #endif
7800 #ifdef CONFIG_CGROUP_NET_CLASSID
7801 case BPF_FUNC_skb_cgroup_classid:
7802 return &bpf_skb_cgroup_classid_proto;
7803 #endif
7804 #ifdef CONFIG_SOCK_CGROUP_DATA
7805 case BPF_FUNC_skb_cgroup_id:
7806 return &bpf_skb_cgroup_id_proto;
7807 case BPF_FUNC_skb_ancestor_cgroup_id:
7808 return &bpf_skb_ancestor_cgroup_id_proto;
7809 #endif
7810 #ifdef CONFIG_INET
7811 case BPF_FUNC_sk_lookup_tcp:
7812 return &bpf_sk_lookup_tcp_proto;
7813 case BPF_FUNC_sk_lookup_udp:
7814 return &bpf_sk_lookup_udp_proto;
7815 case BPF_FUNC_sk_release:
7816 return &bpf_sk_release_proto;
7817 case BPF_FUNC_tcp_sock:
7818 return &bpf_tcp_sock_proto;
7819 case BPF_FUNC_get_listener_sock:
7820 return &bpf_get_listener_sock_proto;
7821 case BPF_FUNC_skc_lookup_tcp:
7822 return &bpf_skc_lookup_tcp_proto;
7823 case BPF_FUNC_tcp_check_syncookie:
7824 return &bpf_tcp_check_syncookie_proto;
7825 case BPF_FUNC_skb_ecn_set_ce:
7826 return &bpf_skb_ecn_set_ce_proto;
7827 case BPF_FUNC_tcp_gen_syncookie:
7828 return &bpf_tcp_gen_syncookie_proto;
7829 case BPF_FUNC_sk_assign:
7830 return &bpf_sk_assign_proto;
7831 case BPF_FUNC_skb_set_tstamp:
7832 return &bpf_skb_set_tstamp_proto;
7833 #endif
7834 default:
7835 return bpf_sk_base_func_proto(func_id);
7836 }
7837 }
7838
7839 static const struct bpf_func_proto *
xdp_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7840 xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7841 {
7842 switch (func_id) {
7843 case BPF_FUNC_perf_event_output:
7844 return &bpf_xdp_event_output_proto;
7845 case BPF_FUNC_get_smp_processor_id:
7846 return &bpf_get_smp_processor_id_proto;
7847 case BPF_FUNC_csum_diff:
7848 return &bpf_csum_diff_proto;
7849 case BPF_FUNC_xdp_adjust_head:
7850 return &bpf_xdp_adjust_head_proto;
7851 case BPF_FUNC_xdp_adjust_meta:
7852 return &bpf_xdp_adjust_meta_proto;
7853 case BPF_FUNC_redirect:
7854 return &bpf_xdp_redirect_proto;
7855 case BPF_FUNC_redirect_map:
7856 return &bpf_xdp_redirect_map_proto;
7857 case BPF_FUNC_xdp_adjust_tail:
7858 return &bpf_xdp_adjust_tail_proto;
7859 case BPF_FUNC_xdp_get_buff_len:
7860 return &bpf_xdp_get_buff_len_proto;
7861 case BPF_FUNC_xdp_load_bytes:
7862 return &bpf_xdp_load_bytes_proto;
7863 case BPF_FUNC_xdp_store_bytes:
7864 return &bpf_xdp_store_bytes_proto;
7865 case BPF_FUNC_fib_lookup:
7866 return &bpf_xdp_fib_lookup_proto;
7867 case BPF_FUNC_check_mtu:
7868 return &bpf_xdp_check_mtu_proto;
7869 #ifdef CONFIG_INET
7870 case BPF_FUNC_sk_lookup_udp:
7871 return &bpf_xdp_sk_lookup_udp_proto;
7872 case BPF_FUNC_sk_lookup_tcp:
7873 return &bpf_xdp_sk_lookup_tcp_proto;
7874 case BPF_FUNC_sk_release:
7875 return &bpf_sk_release_proto;
7876 case BPF_FUNC_skc_lookup_tcp:
7877 return &bpf_xdp_skc_lookup_tcp_proto;
7878 case BPF_FUNC_tcp_check_syncookie:
7879 return &bpf_tcp_check_syncookie_proto;
7880 case BPF_FUNC_tcp_gen_syncookie:
7881 return &bpf_tcp_gen_syncookie_proto;
7882 #endif
7883 default:
7884 return bpf_sk_base_func_proto(func_id);
7885 }
7886 }
7887
7888 const struct bpf_func_proto bpf_sock_map_update_proto __weak;
7889 const struct bpf_func_proto bpf_sock_hash_update_proto __weak;
7890
7891 static const struct bpf_func_proto *
sock_ops_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7892 sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7893 {
7894 switch (func_id) {
7895 case BPF_FUNC_setsockopt:
7896 return &bpf_sock_ops_setsockopt_proto;
7897 case BPF_FUNC_getsockopt:
7898 return &bpf_sock_ops_getsockopt_proto;
7899 case BPF_FUNC_sock_ops_cb_flags_set:
7900 return &bpf_sock_ops_cb_flags_set_proto;
7901 case BPF_FUNC_sock_map_update:
7902 return &bpf_sock_map_update_proto;
7903 case BPF_FUNC_sock_hash_update:
7904 return &bpf_sock_hash_update_proto;
7905 case BPF_FUNC_get_socket_cookie:
7906 return &bpf_get_socket_cookie_sock_ops_proto;
7907 case BPF_FUNC_get_local_storage:
7908 return &bpf_get_local_storage_proto;
7909 case BPF_FUNC_perf_event_output:
7910 return &bpf_event_output_data_proto;
7911 case BPF_FUNC_sk_storage_get:
7912 return &bpf_sk_storage_get_proto;
7913 case BPF_FUNC_sk_storage_delete:
7914 return &bpf_sk_storage_delete_proto;
7915 case BPF_FUNC_get_netns_cookie:
7916 return &bpf_get_netns_cookie_sock_ops_proto;
7917 #ifdef CONFIG_INET
7918 case BPF_FUNC_load_hdr_opt:
7919 return &bpf_sock_ops_load_hdr_opt_proto;
7920 case BPF_FUNC_store_hdr_opt:
7921 return &bpf_sock_ops_store_hdr_opt_proto;
7922 case BPF_FUNC_reserve_hdr_opt:
7923 return &bpf_sock_ops_reserve_hdr_opt_proto;
7924 case BPF_FUNC_tcp_sock:
7925 return &bpf_tcp_sock_proto;
7926 #endif /* CONFIG_INET */
7927 default:
7928 return bpf_sk_base_func_proto(func_id);
7929 }
7930 }
7931
7932 const struct bpf_func_proto bpf_msg_redirect_map_proto __weak;
7933 const struct bpf_func_proto bpf_msg_redirect_hash_proto __weak;
7934
7935 static const struct bpf_func_proto *
sk_msg_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7936 sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7937 {
7938 switch (func_id) {
7939 case BPF_FUNC_msg_redirect_map:
7940 return &bpf_msg_redirect_map_proto;
7941 case BPF_FUNC_msg_redirect_hash:
7942 return &bpf_msg_redirect_hash_proto;
7943 case BPF_FUNC_msg_apply_bytes:
7944 return &bpf_msg_apply_bytes_proto;
7945 case BPF_FUNC_msg_cork_bytes:
7946 return &bpf_msg_cork_bytes_proto;
7947 case BPF_FUNC_msg_pull_data:
7948 return &bpf_msg_pull_data_proto;
7949 case BPF_FUNC_msg_push_data:
7950 return &bpf_msg_push_data_proto;
7951 case BPF_FUNC_msg_pop_data:
7952 return &bpf_msg_pop_data_proto;
7953 case BPF_FUNC_perf_event_output:
7954 return &bpf_event_output_data_proto;
7955 case BPF_FUNC_get_current_uid_gid:
7956 return &bpf_get_current_uid_gid_proto;
7957 case BPF_FUNC_get_current_pid_tgid:
7958 return &bpf_get_current_pid_tgid_proto;
7959 case BPF_FUNC_sk_storage_get:
7960 return &bpf_sk_storage_get_proto;
7961 case BPF_FUNC_sk_storage_delete:
7962 return &bpf_sk_storage_delete_proto;
7963 case BPF_FUNC_get_netns_cookie:
7964 return &bpf_get_netns_cookie_sk_msg_proto;
7965 #ifdef CONFIG_CGROUPS
7966 case BPF_FUNC_get_current_cgroup_id:
7967 return &bpf_get_current_cgroup_id_proto;
7968 case BPF_FUNC_get_current_ancestor_cgroup_id:
7969 return &bpf_get_current_ancestor_cgroup_id_proto;
7970 #endif
7971 #ifdef CONFIG_CGROUP_NET_CLASSID
7972 case BPF_FUNC_get_cgroup_classid:
7973 return &bpf_get_cgroup_classid_curr_proto;
7974 #endif
7975 default:
7976 return bpf_sk_base_func_proto(func_id);
7977 }
7978 }
7979
7980 const struct bpf_func_proto bpf_sk_redirect_map_proto __weak;
7981 const struct bpf_func_proto bpf_sk_redirect_hash_proto __weak;
7982
7983 static const struct bpf_func_proto *
sk_skb_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)7984 sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
7985 {
7986 switch (func_id) {
7987 case BPF_FUNC_skb_store_bytes:
7988 return &bpf_skb_store_bytes_proto;
7989 case BPF_FUNC_skb_load_bytes:
7990 return &bpf_skb_load_bytes_proto;
7991 case BPF_FUNC_skb_pull_data:
7992 return &sk_skb_pull_data_proto;
7993 case BPF_FUNC_skb_change_tail:
7994 return &sk_skb_change_tail_proto;
7995 case BPF_FUNC_skb_change_head:
7996 return &sk_skb_change_head_proto;
7997 case BPF_FUNC_skb_adjust_room:
7998 return &sk_skb_adjust_room_proto;
7999 case BPF_FUNC_get_socket_cookie:
8000 return &bpf_get_socket_cookie_proto;
8001 case BPF_FUNC_get_socket_uid:
8002 return &bpf_get_socket_uid_proto;
8003 case BPF_FUNC_sk_redirect_map:
8004 return &bpf_sk_redirect_map_proto;
8005 case BPF_FUNC_sk_redirect_hash:
8006 return &bpf_sk_redirect_hash_proto;
8007 case BPF_FUNC_perf_event_output:
8008 return &bpf_skb_event_output_proto;
8009 #ifdef CONFIG_INET
8010 case BPF_FUNC_sk_lookup_tcp:
8011 return &bpf_sk_lookup_tcp_proto;
8012 case BPF_FUNC_sk_lookup_udp:
8013 return &bpf_sk_lookup_udp_proto;
8014 case BPF_FUNC_sk_release:
8015 return &bpf_sk_release_proto;
8016 case BPF_FUNC_skc_lookup_tcp:
8017 return &bpf_skc_lookup_tcp_proto;
8018 #endif
8019 default:
8020 return bpf_sk_base_func_proto(func_id);
8021 }
8022 }
8023
8024 static const struct bpf_func_proto *
flow_dissector_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8025 flow_dissector_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8026 {
8027 switch (func_id) {
8028 case BPF_FUNC_skb_load_bytes:
8029 return &bpf_flow_dissector_load_bytes_proto;
8030 default:
8031 return bpf_sk_base_func_proto(func_id);
8032 }
8033 }
8034
8035 static const struct bpf_func_proto *
lwt_out_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8036 lwt_out_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8037 {
8038 switch (func_id) {
8039 case BPF_FUNC_skb_load_bytes:
8040 return &bpf_skb_load_bytes_proto;
8041 case BPF_FUNC_skb_pull_data:
8042 return &bpf_skb_pull_data_proto;
8043 case BPF_FUNC_csum_diff:
8044 return &bpf_csum_diff_proto;
8045 case BPF_FUNC_get_cgroup_classid:
8046 return &bpf_get_cgroup_classid_proto;
8047 case BPF_FUNC_get_route_realm:
8048 return &bpf_get_route_realm_proto;
8049 case BPF_FUNC_get_hash_recalc:
8050 return &bpf_get_hash_recalc_proto;
8051 case BPF_FUNC_perf_event_output:
8052 return &bpf_skb_event_output_proto;
8053 case BPF_FUNC_get_smp_processor_id:
8054 return &bpf_get_smp_processor_id_proto;
8055 case BPF_FUNC_skb_under_cgroup:
8056 return &bpf_skb_under_cgroup_proto;
8057 default:
8058 return bpf_sk_base_func_proto(func_id);
8059 }
8060 }
8061
8062 static const struct bpf_func_proto *
lwt_in_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8063 lwt_in_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8064 {
8065 switch (func_id) {
8066 case BPF_FUNC_lwt_push_encap:
8067 return &bpf_lwt_in_push_encap_proto;
8068 default:
8069 return lwt_out_func_proto(func_id, prog);
8070 }
8071 }
8072
8073 static const struct bpf_func_proto *
lwt_xmit_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8074 lwt_xmit_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8075 {
8076 switch (func_id) {
8077 case BPF_FUNC_skb_get_tunnel_key:
8078 return &bpf_skb_get_tunnel_key_proto;
8079 case BPF_FUNC_skb_set_tunnel_key:
8080 return bpf_get_skb_set_tunnel_proto(func_id);
8081 case BPF_FUNC_skb_get_tunnel_opt:
8082 return &bpf_skb_get_tunnel_opt_proto;
8083 case BPF_FUNC_skb_set_tunnel_opt:
8084 return bpf_get_skb_set_tunnel_proto(func_id);
8085 case BPF_FUNC_redirect:
8086 return &bpf_redirect_proto;
8087 case BPF_FUNC_clone_redirect:
8088 return &bpf_clone_redirect_proto;
8089 case BPF_FUNC_skb_change_tail:
8090 return &bpf_skb_change_tail_proto;
8091 case BPF_FUNC_skb_change_head:
8092 return &bpf_skb_change_head_proto;
8093 case BPF_FUNC_skb_store_bytes:
8094 return &bpf_skb_store_bytes_proto;
8095 case BPF_FUNC_csum_update:
8096 return &bpf_csum_update_proto;
8097 case BPF_FUNC_csum_level:
8098 return &bpf_csum_level_proto;
8099 case BPF_FUNC_l3_csum_replace:
8100 return &bpf_l3_csum_replace_proto;
8101 case BPF_FUNC_l4_csum_replace:
8102 return &bpf_l4_csum_replace_proto;
8103 case BPF_FUNC_set_hash_invalid:
8104 return &bpf_set_hash_invalid_proto;
8105 case BPF_FUNC_lwt_push_encap:
8106 return &bpf_lwt_xmit_push_encap_proto;
8107 default:
8108 return lwt_out_func_proto(func_id, prog);
8109 }
8110 }
8111
8112 static const struct bpf_func_proto *
lwt_seg6local_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)8113 lwt_seg6local_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
8114 {
8115 switch (func_id) {
8116 #if IS_ENABLED(CONFIG_IPV6_SEG6_BPF)
8117 case BPF_FUNC_lwt_seg6_store_bytes:
8118 return &bpf_lwt_seg6_store_bytes_proto;
8119 case BPF_FUNC_lwt_seg6_action:
8120 return &bpf_lwt_seg6_action_proto;
8121 case BPF_FUNC_lwt_seg6_adjust_srh:
8122 return &bpf_lwt_seg6_adjust_srh_proto;
8123 #endif
8124 default:
8125 return lwt_out_func_proto(func_id, prog);
8126 }
8127 }
8128
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)8129 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
8130 const struct bpf_prog *prog,
8131 struct bpf_insn_access_aux *info)
8132 {
8133 const int size_default = sizeof(__u32);
8134
8135 if (off < 0 || off >= sizeof(struct __sk_buff))
8136 return false;
8137
8138 /* The verifier guarantees that size > 0. */
8139 if (off % size != 0)
8140 return false;
8141
8142 switch (off) {
8143 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8144 if (off + size > offsetofend(struct __sk_buff, cb[4]))
8145 return false;
8146 break;
8147 case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
8148 case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
8149 case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
8150 case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
8151 case bpf_ctx_range(struct __sk_buff, data):
8152 case bpf_ctx_range(struct __sk_buff, data_meta):
8153 case bpf_ctx_range(struct __sk_buff, data_end):
8154 if (size != size_default)
8155 return false;
8156 break;
8157 case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
8158 return false;
8159 case bpf_ctx_range(struct __sk_buff, hwtstamp):
8160 if (type == BPF_WRITE || size != sizeof(__u64))
8161 return false;
8162 break;
8163 case bpf_ctx_range(struct __sk_buff, tstamp):
8164 if (size != sizeof(__u64))
8165 return false;
8166 break;
8167 case offsetof(struct __sk_buff, sk):
8168 if (type == BPF_WRITE || size != sizeof(__u64))
8169 return false;
8170 info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
8171 break;
8172 case offsetof(struct __sk_buff, tstamp_type):
8173 return false;
8174 case offsetofend(struct __sk_buff, tstamp_type) ... offsetof(struct __sk_buff, hwtstamp) - 1:
8175 /* Explicitly prohibit access to padding in __sk_buff. */
8176 return false;
8177 default:
8178 /* Only narrow read access allowed for now. */
8179 if (type == BPF_WRITE) {
8180 if (size != size_default)
8181 return false;
8182 } else {
8183 bpf_ctx_record_field_size(info, size_default);
8184 if (!bpf_ctx_narrow_access_ok(off, size, size_default))
8185 return false;
8186 }
8187 }
8188
8189 return true;
8190 }
8191
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)8192 static bool sk_filter_is_valid_access(int off, int size,
8193 enum bpf_access_type type,
8194 const struct bpf_prog *prog,
8195 struct bpf_insn_access_aux *info)
8196 {
8197 switch (off) {
8198 case bpf_ctx_range(struct __sk_buff, tc_classid):
8199 case bpf_ctx_range(struct __sk_buff, data):
8200 case bpf_ctx_range(struct __sk_buff, data_meta):
8201 case bpf_ctx_range(struct __sk_buff, data_end):
8202 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8203 case bpf_ctx_range(struct __sk_buff, tstamp):
8204 case bpf_ctx_range(struct __sk_buff, wire_len):
8205 case bpf_ctx_range(struct __sk_buff, hwtstamp):
8206 return false;
8207 }
8208
8209 if (type == BPF_WRITE) {
8210 switch (off) {
8211 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8212 break;
8213 default:
8214 return false;
8215 }
8216 }
8217
8218 return bpf_skb_is_valid_access(off, size, type, prog, info);
8219 }
8220
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)8221 static bool cg_skb_is_valid_access(int off, int size,
8222 enum bpf_access_type type,
8223 const struct bpf_prog *prog,
8224 struct bpf_insn_access_aux *info)
8225 {
8226 switch (off) {
8227 case bpf_ctx_range(struct __sk_buff, tc_classid):
8228 case bpf_ctx_range(struct __sk_buff, data_meta):
8229 case bpf_ctx_range(struct __sk_buff, wire_len):
8230 return false;
8231 case bpf_ctx_range(struct __sk_buff, data):
8232 case bpf_ctx_range(struct __sk_buff, data_end):
8233 if (!bpf_capable())
8234 return false;
8235 break;
8236 }
8237
8238 if (type == BPF_WRITE) {
8239 switch (off) {
8240 case bpf_ctx_range(struct __sk_buff, mark):
8241 case bpf_ctx_range(struct __sk_buff, priority):
8242 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8243 break;
8244 case bpf_ctx_range(struct __sk_buff, tstamp):
8245 if (!bpf_capable())
8246 return false;
8247 break;
8248 default:
8249 return false;
8250 }
8251 }
8252
8253 switch (off) {
8254 case bpf_ctx_range(struct __sk_buff, data):
8255 info->reg_type = PTR_TO_PACKET;
8256 break;
8257 case bpf_ctx_range(struct __sk_buff, data_end):
8258 info->reg_type = PTR_TO_PACKET_END;
8259 break;
8260 }
8261
8262 return bpf_skb_is_valid_access(off, size, type, prog, info);
8263 }
8264
lwt_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8265 static bool lwt_is_valid_access(int off, int size,
8266 enum bpf_access_type type,
8267 const struct bpf_prog *prog,
8268 struct bpf_insn_access_aux *info)
8269 {
8270 switch (off) {
8271 case bpf_ctx_range(struct __sk_buff, tc_classid):
8272 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8273 case bpf_ctx_range(struct __sk_buff, data_meta):
8274 case bpf_ctx_range(struct __sk_buff, tstamp):
8275 case bpf_ctx_range(struct __sk_buff, wire_len):
8276 case bpf_ctx_range(struct __sk_buff, hwtstamp):
8277 return false;
8278 }
8279
8280 if (type == BPF_WRITE) {
8281 switch (off) {
8282 case bpf_ctx_range(struct __sk_buff, mark):
8283 case bpf_ctx_range(struct __sk_buff, priority):
8284 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8285 break;
8286 default:
8287 return false;
8288 }
8289 }
8290
8291 switch (off) {
8292 case bpf_ctx_range(struct __sk_buff, data):
8293 info->reg_type = PTR_TO_PACKET;
8294 break;
8295 case bpf_ctx_range(struct __sk_buff, data_end):
8296 info->reg_type = PTR_TO_PACKET_END;
8297 break;
8298 }
8299
8300 return bpf_skb_is_valid_access(off, size, type, prog, info);
8301 }
8302
8303 /* Attach type specific accesses */
__sock_filter_check_attach_type(int off,enum bpf_access_type access_type,enum bpf_attach_type attach_type)8304 static bool __sock_filter_check_attach_type(int off,
8305 enum bpf_access_type access_type,
8306 enum bpf_attach_type attach_type)
8307 {
8308 switch (off) {
8309 case offsetof(struct bpf_sock, bound_dev_if):
8310 case offsetof(struct bpf_sock, mark):
8311 case offsetof(struct bpf_sock, priority):
8312 switch (attach_type) {
8313 case BPF_CGROUP_INET_SOCK_CREATE:
8314 case BPF_CGROUP_INET_SOCK_RELEASE:
8315 goto full_access;
8316 default:
8317 return false;
8318 }
8319 case bpf_ctx_range(struct bpf_sock, src_ip4):
8320 switch (attach_type) {
8321 case BPF_CGROUP_INET4_POST_BIND:
8322 goto read_only;
8323 default:
8324 return false;
8325 }
8326 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
8327 switch (attach_type) {
8328 case BPF_CGROUP_INET6_POST_BIND:
8329 goto read_only;
8330 default:
8331 return false;
8332 }
8333 case bpf_ctx_range(struct bpf_sock, src_port):
8334 switch (attach_type) {
8335 case BPF_CGROUP_INET4_POST_BIND:
8336 case BPF_CGROUP_INET6_POST_BIND:
8337 goto read_only;
8338 default:
8339 return false;
8340 }
8341 }
8342 read_only:
8343 return access_type == BPF_READ;
8344 full_access:
8345 return true;
8346 }
8347
bpf_sock_common_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)8348 bool bpf_sock_common_is_valid_access(int off, int size,
8349 enum bpf_access_type type,
8350 struct bpf_insn_access_aux *info)
8351 {
8352 switch (off) {
8353 case bpf_ctx_range_till(struct bpf_sock, type, priority):
8354 return false;
8355 default:
8356 return bpf_sock_is_valid_access(off, size, type, info);
8357 }
8358 }
8359
bpf_sock_is_valid_access(int off,int size,enum bpf_access_type type,struct bpf_insn_access_aux * info)8360 bool bpf_sock_is_valid_access(int off, int size, enum bpf_access_type type,
8361 struct bpf_insn_access_aux *info)
8362 {
8363 const int size_default = sizeof(__u32);
8364 int field_size;
8365
8366 if (off < 0 || off >= sizeof(struct bpf_sock))
8367 return false;
8368 if (off % size != 0)
8369 return false;
8370
8371 switch (off) {
8372 case offsetof(struct bpf_sock, state):
8373 case offsetof(struct bpf_sock, family):
8374 case offsetof(struct bpf_sock, type):
8375 case offsetof(struct bpf_sock, protocol):
8376 case offsetof(struct bpf_sock, src_port):
8377 case offsetof(struct bpf_sock, rx_queue_mapping):
8378 case bpf_ctx_range(struct bpf_sock, src_ip4):
8379 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
8380 case bpf_ctx_range(struct bpf_sock, dst_ip4):
8381 case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
8382 bpf_ctx_record_field_size(info, size_default);
8383 return bpf_ctx_narrow_access_ok(off, size, size_default);
8384 case bpf_ctx_range(struct bpf_sock, dst_port):
8385 field_size = size == size_default ?
8386 size_default : sizeof_field(struct bpf_sock, dst_port);
8387 bpf_ctx_record_field_size(info, field_size);
8388 return bpf_ctx_narrow_access_ok(off, size, field_size);
8389 case offsetofend(struct bpf_sock, dst_port) ...
8390 offsetof(struct bpf_sock, dst_ip4) - 1:
8391 return false;
8392 }
8393
8394 return size == size_default;
8395 }
8396
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)8397 static bool sock_filter_is_valid_access(int off, int size,
8398 enum bpf_access_type type,
8399 const struct bpf_prog *prog,
8400 struct bpf_insn_access_aux *info)
8401 {
8402 if (!bpf_sock_is_valid_access(off, size, type, info))
8403 return false;
8404 return __sock_filter_check_attach_type(off, type,
8405 prog->expected_attach_type);
8406 }
8407
bpf_noop_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8408 static int bpf_noop_prologue(struct bpf_insn *insn_buf, bool direct_write,
8409 const struct bpf_prog *prog)
8410 {
8411 /* Neither direct read nor direct write requires any preliminary
8412 * action.
8413 */
8414 return 0;
8415 }
8416
bpf_unclone_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog,int drop_verdict)8417 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
8418 const struct bpf_prog *prog, int drop_verdict)
8419 {
8420 struct bpf_insn *insn = insn_buf;
8421
8422 if (!direct_write)
8423 return 0;
8424
8425 /* if (!skb->cloned)
8426 * goto start;
8427 *
8428 * (Fast-path, otherwise approximation that we might be
8429 * a clone, do the rest in helper.)
8430 */
8431 *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET);
8432 *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
8433 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
8434
8435 /* ret = bpf_skb_pull_data(skb, 0); */
8436 *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
8437 *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
8438 *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
8439 BPF_FUNC_skb_pull_data);
8440 /* if (!ret)
8441 * goto restore;
8442 * return TC_ACT_SHOT;
8443 */
8444 *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
8445 *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
8446 *insn++ = BPF_EXIT_INSN();
8447
8448 /* restore: */
8449 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
8450 /* start: */
8451 *insn++ = prog->insnsi[0];
8452
8453 return insn - insn_buf;
8454 }
8455
bpf_gen_ld_abs(const struct bpf_insn * orig,struct bpf_insn * insn_buf)8456 static int bpf_gen_ld_abs(const struct bpf_insn *orig,
8457 struct bpf_insn *insn_buf)
8458 {
8459 bool indirect = BPF_MODE(orig->code) == BPF_IND;
8460 struct bpf_insn *insn = insn_buf;
8461
8462 if (!indirect) {
8463 *insn++ = BPF_MOV64_IMM(BPF_REG_2, orig->imm);
8464 } else {
8465 *insn++ = BPF_MOV64_REG(BPF_REG_2, orig->src_reg);
8466 if (orig->imm)
8467 *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, orig->imm);
8468 }
8469 /* We're guaranteed here that CTX is in R6. */
8470 *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_CTX);
8471
8472 switch (BPF_SIZE(orig->code)) {
8473 case BPF_B:
8474 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_8_no_cache);
8475 break;
8476 case BPF_H:
8477 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_16_no_cache);
8478 break;
8479 case BPF_W:
8480 *insn++ = BPF_EMIT_CALL(bpf_skb_load_helper_32_no_cache);
8481 break;
8482 }
8483
8484 *insn++ = BPF_JMP_IMM(BPF_JSGE, BPF_REG_0, 0, 2);
8485 *insn++ = BPF_ALU32_REG(BPF_XOR, BPF_REG_0, BPF_REG_0);
8486 *insn++ = BPF_EXIT_INSN();
8487
8488 return insn - insn_buf;
8489 }
8490
tc_cls_act_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8491 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
8492 const struct bpf_prog *prog)
8493 {
8494 return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
8495 }
8496
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)8497 static bool tc_cls_act_is_valid_access(int off, int size,
8498 enum bpf_access_type type,
8499 const struct bpf_prog *prog,
8500 struct bpf_insn_access_aux *info)
8501 {
8502 if (type == BPF_WRITE) {
8503 switch (off) {
8504 case bpf_ctx_range(struct __sk_buff, mark):
8505 case bpf_ctx_range(struct __sk_buff, tc_index):
8506 case bpf_ctx_range(struct __sk_buff, priority):
8507 case bpf_ctx_range(struct __sk_buff, tc_classid):
8508 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
8509 case bpf_ctx_range(struct __sk_buff, tstamp):
8510 case bpf_ctx_range(struct __sk_buff, queue_mapping):
8511 break;
8512 default:
8513 return false;
8514 }
8515 }
8516
8517 switch (off) {
8518 case bpf_ctx_range(struct __sk_buff, data):
8519 info->reg_type = PTR_TO_PACKET;
8520 break;
8521 case bpf_ctx_range(struct __sk_buff, data_meta):
8522 info->reg_type = PTR_TO_PACKET_META;
8523 break;
8524 case bpf_ctx_range(struct __sk_buff, data_end):
8525 info->reg_type = PTR_TO_PACKET_END;
8526 break;
8527 case bpf_ctx_range_till(struct __sk_buff, family, local_port):
8528 return false;
8529 case offsetof(struct __sk_buff, tstamp_type):
8530 /* The convert_ctx_access() on reading and writing
8531 * __sk_buff->tstamp depends on whether the bpf prog
8532 * has used __sk_buff->tstamp_type or not.
8533 * Thus, we need to set prog->tstamp_type_access
8534 * earlier during is_valid_access() here.
8535 */
8536 ((struct bpf_prog *)prog)->tstamp_type_access = 1;
8537 return size == sizeof(__u8);
8538 }
8539
8540 return bpf_skb_is_valid_access(off, size, type, prog, info);
8541 }
8542
__is_valid_xdp_access(int off,int size)8543 static bool __is_valid_xdp_access(int off, int size)
8544 {
8545 if (off < 0 || off >= sizeof(struct xdp_md))
8546 return false;
8547 if (off % size != 0)
8548 return false;
8549 if (size != sizeof(__u32))
8550 return false;
8551
8552 return true;
8553 }
8554
xdp_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)8555 static bool xdp_is_valid_access(int off, int size,
8556 enum bpf_access_type type,
8557 const struct bpf_prog *prog,
8558 struct bpf_insn_access_aux *info)
8559 {
8560 if (prog->expected_attach_type != BPF_XDP_DEVMAP) {
8561 switch (off) {
8562 case offsetof(struct xdp_md, egress_ifindex):
8563 return false;
8564 }
8565 }
8566
8567 if (type == BPF_WRITE) {
8568 if (bpf_prog_is_dev_bound(prog->aux)) {
8569 switch (off) {
8570 case offsetof(struct xdp_md, rx_queue_index):
8571 return __is_valid_xdp_access(off, size);
8572 }
8573 }
8574 return false;
8575 }
8576
8577 switch (off) {
8578 case offsetof(struct xdp_md, data):
8579 info->reg_type = PTR_TO_PACKET;
8580 break;
8581 case offsetof(struct xdp_md, data_meta):
8582 info->reg_type = PTR_TO_PACKET_META;
8583 break;
8584 case offsetof(struct xdp_md, data_end):
8585 info->reg_type = PTR_TO_PACKET_END;
8586 break;
8587 }
8588
8589 return __is_valid_xdp_access(off, size);
8590 }
8591
bpf_warn_invalid_xdp_action(struct net_device * dev,struct bpf_prog * prog,u32 act)8592 void bpf_warn_invalid_xdp_action(struct net_device *dev, struct bpf_prog *prog, u32 act)
8593 {
8594 const u32 act_max = XDP_REDIRECT;
8595
8596 pr_warn_once("%s XDP return value %u on prog %s (id %d) dev %s, expect packet loss!\n",
8597 act > act_max ? "Illegal" : "Driver unsupported",
8598 act, prog->aux->name, prog->aux->id, dev ? dev->name : "N/A");
8599 }
8600 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
8601
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)8602 static bool sock_addr_is_valid_access(int off, int size,
8603 enum bpf_access_type type,
8604 const struct bpf_prog *prog,
8605 struct bpf_insn_access_aux *info)
8606 {
8607 const int size_default = sizeof(__u32);
8608
8609 if (off < 0 || off >= sizeof(struct bpf_sock_addr))
8610 return false;
8611 if (off % size != 0)
8612 return false;
8613
8614 /* Disallow access to IPv6 fields from IPv4 contex and vise
8615 * versa.
8616 */
8617 switch (off) {
8618 case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
8619 switch (prog->expected_attach_type) {
8620 case BPF_CGROUP_INET4_BIND:
8621 case BPF_CGROUP_INET4_CONNECT:
8622 case BPF_CGROUP_INET4_GETPEERNAME:
8623 case BPF_CGROUP_INET4_GETSOCKNAME:
8624 case BPF_CGROUP_UDP4_SENDMSG:
8625 case BPF_CGROUP_UDP4_RECVMSG:
8626 break;
8627 default:
8628 return false;
8629 }
8630 break;
8631 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
8632 switch (prog->expected_attach_type) {
8633 case BPF_CGROUP_INET6_BIND:
8634 case BPF_CGROUP_INET6_CONNECT:
8635 case BPF_CGROUP_INET6_GETPEERNAME:
8636 case BPF_CGROUP_INET6_GETSOCKNAME:
8637 case BPF_CGROUP_UDP6_SENDMSG:
8638 case BPF_CGROUP_UDP6_RECVMSG:
8639 break;
8640 default:
8641 return false;
8642 }
8643 break;
8644 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
8645 switch (prog->expected_attach_type) {
8646 case BPF_CGROUP_UDP4_SENDMSG:
8647 break;
8648 default:
8649 return false;
8650 }
8651 break;
8652 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
8653 msg_src_ip6[3]):
8654 switch (prog->expected_attach_type) {
8655 case BPF_CGROUP_UDP6_SENDMSG:
8656 break;
8657 default:
8658 return false;
8659 }
8660 break;
8661 }
8662
8663 switch (off) {
8664 case bpf_ctx_range(struct bpf_sock_addr, user_ip4):
8665 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
8666 case bpf_ctx_range(struct bpf_sock_addr, msg_src_ip4):
8667 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
8668 msg_src_ip6[3]):
8669 case bpf_ctx_range(struct bpf_sock_addr, user_port):
8670 if (type == BPF_READ) {
8671 bpf_ctx_record_field_size(info, size_default);
8672
8673 if (bpf_ctx_wide_access_ok(off, size,
8674 struct bpf_sock_addr,
8675 user_ip6))
8676 return true;
8677
8678 if (bpf_ctx_wide_access_ok(off, size,
8679 struct bpf_sock_addr,
8680 msg_src_ip6))
8681 return true;
8682
8683 if (!bpf_ctx_narrow_access_ok(off, size, size_default))
8684 return false;
8685 } else {
8686 if (bpf_ctx_wide_access_ok(off, size,
8687 struct bpf_sock_addr,
8688 user_ip6))
8689 return true;
8690
8691 if (bpf_ctx_wide_access_ok(off, size,
8692 struct bpf_sock_addr,
8693 msg_src_ip6))
8694 return true;
8695
8696 if (size != size_default)
8697 return false;
8698 }
8699 break;
8700 case offsetof(struct bpf_sock_addr, sk):
8701 if (type != BPF_READ)
8702 return false;
8703 if (size != sizeof(__u64))
8704 return false;
8705 info->reg_type = PTR_TO_SOCKET;
8706 break;
8707 default:
8708 if (type == BPF_READ) {
8709 if (size != size_default)
8710 return false;
8711 } else {
8712 return false;
8713 }
8714 }
8715
8716 return true;
8717 }
8718
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)8719 static bool sock_ops_is_valid_access(int off, int size,
8720 enum bpf_access_type type,
8721 const struct bpf_prog *prog,
8722 struct bpf_insn_access_aux *info)
8723 {
8724 const int size_default = sizeof(__u32);
8725
8726 if (off < 0 || off >= sizeof(struct bpf_sock_ops))
8727 return false;
8728
8729 /* The verifier guarantees that size > 0. */
8730 if (off % size != 0)
8731 return false;
8732
8733 if (type == BPF_WRITE) {
8734 switch (off) {
8735 case offsetof(struct bpf_sock_ops, reply):
8736 case offsetof(struct bpf_sock_ops, sk_txhash):
8737 if (size != size_default)
8738 return false;
8739 break;
8740 default:
8741 return false;
8742 }
8743 } else {
8744 switch (off) {
8745 case bpf_ctx_range_till(struct bpf_sock_ops, bytes_received,
8746 bytes_acked):
8747 if (size != sizeof(__u64))
8748 return false;
8749 break;
8750 case offsetof(struct bpf_sock_ops, sk):
8751 if (size != sizeof(__u64))
8752 return false;
8753 info->reg_type = PTR_TO_SOCKET_OR_NULL;
8754 break;
8755 case offsetof(struct bpf_sock_ops, skb_data):
8756 if (size != sizeof(__u64))
8757 return false;
8758 info->reg_type = PTR_TO_PACKET;
8759 break;
8760 case offsetof(struct bpf_sock_ops, skb_data_end):
8761 if (size != sizeof(__u64))
8762 return false;
8763 info->reg_type = PTR_TO_PACKET_END;
8764 break;
8765 case offsetof(struct bpf_sock_ops, skb_tcp_flags):
8766 bpf_ctx_record_field_size(info, size_default);
8767 return bpf_ctx_narrow_access_ok(off, size,
8768 size_default);
8769 default:
8770 if (size != size_default)
8771 return false;
8772 break;
8773 }
8774 }
8775
8776 return true;
8777 }
8778
sk_skb_prologue(struct bpf_insn * insn_buf,bool direct_write,const struct bpf_prog * prog)8779 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
8780 const struct bpf_prog *prog)
8781 {
8782 return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
8783 }
8784
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)8785 static bool sk_skb_is_valid_access(int off, int size,
8786 enum bpf_access_type type,
8787 const struct bpf_prog *prog,
8788 struct bpf_insn_access_aux *info)
8789 {
8790 switch (off) {
8791 case bpf_ctx_range(struct __sk_buff, tc_classid):
8792 case bpf_ctx_range(struct __sk_buff, data_meta):
8793 case bpf_ctx_range(struct __sk_buff, tstamp):
8794 case bpf_ctx_range(struct __sk_buff, wire_len):
8795 case bpf_ctx_range(struct __sk_buff, hwtstamp):
8796 return false;
8797 }
8798
8799 if (type == BPF_WRITE) {
8800 switch (off) {
8801 case bpf_ctx_range(struct __sk_buff, tc_index):
8802 case bpf_ctx_range(struct __sk_buff, priority):
8803 break;
8804 default:
8805 return false;
8806 }
8807 }
8808
8809 switch (off) {
8810 case bpf_ctx_range(struct __sk_buff, mark):
8811 return false;
8812 case bpf_ctx_range(struct __sk_buff, data):
8813 info->reg_type = PTR_TO_PACKET;
8814 break;
8815 case bpf_ctx_range(struct __sk_buff, data_end):
8816 info->reg_type = PTR_TO_PACKET_END;
8817 break;
8818 }
8819
8820 return bpf_skb_is_valid_access(off, size, type, prog, info);
8821 }
8822
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)8823 static bool sk_msg_is_valid_access(int off, int size,
8824 enum bpf_access_type type,
8825 const struct bpf_prog *prog,
8826 struct bpf_insn_access_aux *info)
8827 {
8828 if (type == BPF_WRITE)
8829 return false;
8830
8831 if (off % size != 0)
8832 return false;
8833
8834 switch (off) {
8835 case offsetof(struct sk_msg_md, data):
8836 info->reg_type = PTR_TO_PACKET;
8837 if (size != sizeof(__u64))
8838 return false;
8839 break;
8840 case offsetof(struct sk_msg_md, data_end):
8841 info->reg_type = PTR_TO_PACKET_END;
8842 if (size != sizeof(__u64))
8843 return false;
8844 break;
8845 case offsetof(struct sk_msg_md, sk):
8846 if (size != sizeof(__u64))
8847 return false;
8848 info->reg_type = PTR_TO_SOCKET;
8849 break;
8850 case bpf_ctx_range(struct sk_msg_md, family):
8851 case bpf_ctx_range(struct sk_msg_md, remote_ip4):
8852 case bpf_ctx_range(struct sk_msg_md, local_ip4):
8853 case bpf_ctx_range_till(struct sk_msg_md, remote_ip6[0], remote_ip6[3]):
8854 case bpf_ctx_range_till(struct sk_msg_md, local_ip6[0], local_ip6[3]):
8855 case bpf_ctx_range(struct sk_msg_md, remote_port):
8856 case bpf_ctx_range(struct sk_msg_md, local_port):
8857 case bpf_ctx_range(struct sk_msg_md, size):
8858 if (size != sizeof(__u32))
8859 return false;
8860 break;
8861 default:
8862 return false;
8863 }
8864 return true;
8865 }
8866
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)8867 static bool flow_dissector_is_valid_access(int off, int size,
8868 enum bpf_access_type type,
8869 const struct bpf_prog *prog,
8870 struct bpf_insn_access_aux *info)
8871 {
8872 const int size_default = sizeof(__u32);
8873
8874 if (off < 0 || off >= sizeof(struct __sk_buff))
8875 return false;
8876
8877 if (type == BPF_WRITE)
8878 return false;
8879
8880 switch (off) {
8881 case bpf_ctx_range(struct __sk_buff, data):
8882 if (size != size_default)
8883 return false;
8884 info->reg_type = PTR_TO_PACKET;
8885 return true;
8886 case bpf_ctx_range(struct __sk_buff, data_end):
8887 if (size != size_default)
8888 return false;
8889 info->reg_type = PTR_TO_PACKET_END;
8890 return true;
8891 case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
8892 if (size != sizeof(__u64))
8893 return false;
8894 info->reg_type = PTR_TO_FLOW_KEYS;
8895 return true;
8896 default:
8897 return false;
8898 }
8899 }
8900
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)8901 static u32 flow_dissector_convert_ctx_access(enum bpf_access_type type,
8902 const struct bpf_insn *si,
8903 struct bpf_insn *insn_buf,
8904 struct bpf_prog *prog,
8905 u32 *target_size)
8906
8907 {
8908 struct bpf_insn *insn = insn_buf;
8909
8910 switch (si->off) {
8911 case offsetof(struct __sk_buff, data):
8912 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data),
8913 si->dst_reg, si->src_reg,
8914 offsetof(struct bpf_flow_dissector, data));
8915 break;
8916
8917 case offsetof(struct __sk_buff, data_end):
8918 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, data_end),
8919 si->dst_reg, si->src_reg,
8920 offsetof(struct bpf_flow_dissector, data_end));
8921 break;
8922
8923 case offsetof(struct __sk_buff, flow_keys):
8924 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_flow_dissector, flow_keys),
8925 si->dst_reg, si->src_reg,
8926 offsetof(struct bpf_flow_dissector, flow_keys));
8927 break;
8928 }
8929
8930 return insn - insn_buf;
8931 }
8932
bpf_convert_tstamp_type_read(const struct bpf_insn * si,struct bpf_insn * insn)8933 static struct bpf_insn *bpf_convert_tstamp_type_read(const struct bpf_insn *si,
8934 struct bpf_insn *insn)
8935 {
8936 __u8 value_reg = si->dst_reg;
8937 __u8 skb_reg = si->src_reg;
8938 /* AX is needed because src_reg and dst_reg could be the same */
8939 __u8 tmp_reg = BPF_REG_AX;
8940
8941 *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg,
8942 PKT_VLAN_PRESENT_OFFSET);
8943 *insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg,
8944 SKB_MONO_DELIVERY_TIME_MASK, 2);
8945 *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_UNSPEC);
8946 *insn++ = BPF_JMP_A(1);
8947 *insn++ = BPF_MOV32_IMM(value_reg, BPF_SKB_TSTAMP_DELIVERY_MONO);
8948
8949 return insn;
8950 }
8951
bpf_convert_shinfo_access(const struct bpf_insn * si,struct bpf_insn * insn)8952 static struct bpf_insn *bpf_convert_shinfo_access(const struct bpf_insn *si,
8953 struct bpf_insn *insn)
8954 {
8955 /* si->dst_reg = skb_shinfo(SKB); */
8956 #ifdef NET_SKBUFF_DATA_USES_OFFSET
8957 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
8958 BPF_REG_AX, si->src_reg,
8959 offsetof(struct sk_buff, end));
8960 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, head),
8961 si->dst_reg, si->src_reg,
8962 offsetof(struct sk_buff, head));
8963 *insn++ = BPF_ALU64_REG(BPF_ADD, si->dst_reg, BPF_REG_AX);
8964 #else
8965 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, end),
8966 si->dst_reg, si->src_reg,
8967 offsetof(struct sk_buff, end));
8968 #endif
8969
8970 return insn;
8971 }
8972
bpf_convert_tstamp_read(const struct bpf_prog * prog,const struct bpf_insn * si,struct bpf_insn * insn)8973 static struct bpf_insn *bpf_convert_tstamp_read(const struct bpf_prog *prog,
8974 const struct bpf_insn *si,
8975 struct bpf_insn *insn)
8976 {
8977 __u8 value_reg = si->dst_reg;
8978 __u8 skb_reg = si->src_reg;
8979
8980 #ifdef CONFIG_NET_CLS_ACT
8981 /* If the tstamp_type is read,
8982 * the bpf prog is aware the tstamp could have delivery time.
8983 * Thus, read skb->tstamp as is if tstamp_type_access is true.
8984 */
8985 if (!prog->tstamp_type_access) {
8986 /* AX is needed because src_reg and dst_reg could be the same */
8987 __u8 tmp_reg = BPF_REG_AX;
8988
8989 *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, PKT_VLAN_PRESENT_OFFSET);
8990 *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg,
8991 TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK);
8992 *insn++ = BPF_JMP32_IMM(BPF_JNE, tmp_reg,
8993 TC_AT_INGRESS_MASK | SKB_MONO_DELIVERY_TIME_MASK, 2);
8994 /* skb->tc_at_ingress && skb->mono_delivery_time,
8995 * read 0 as the (rcv) timestamp.
8996 */
8997 *insn++ = BPF_MOV64_IMM(value_reg, 0);
8998 *insn++ = BPF_JMP_A(1);
8999 }
9000 #endif
9001
9002 *insn++ = BPF_LDX_MEM(BPF_DW, value_reg, skb_reg,
9003 offsetof(struct sk_buff, tstamp));
9004 return insn;
9005 }
9006
bpf_convert_tstamp_write(const struct bpf_prog * prog,const struct bpf_insn * si,struct bpf_insn * insn)9007 static struct bpf_insn *bpf_convert_tstamp_write(const struct bpf_prog *prog,
9008 const struct bpf_insn *si,
9009 struct bpf_insn *insn)
9010 {
9011 __u8 value_reg = si->src_reg;
9012 __u8 skb_reg = si->dst_reg;
9013
9014 #ifdef CONFIG_NET_CLS_ACT
9015 /* If the tstamp_type is read,
9016 * the bpf prog is aware the tstamp could have delivery time.
9017 * Thus, write skb->tstamp as is if tstamp_type_access is true.
9018 * Otherwise, writing at ingress will have to clear the
9019 * mono_delivery_time bit also.
9020 */
9021 if (!prog->tstamp_type_access) {
9022 __u8 tmp_reg = BPF_REG_AX;
9023
9024 *insn++ = BPF_LDX_MEM(BPF_B, tmp_reg, skb_reg, PKT_VLAN_PRESENT_OFFSET);
9025 /* Writing __sk_buff->tstamp as ingress, goto <clear> */
9026 *insn++ = BPF_JMP32_IMM(BPF_JSET, tmp_reg, TC_AT_INGRESS_MASK, 1);
9027 /* goto <store> */
9028 *insn++ = BPF_JMP_A(2);
9029 /* <clear>: mono_delivery_time */
9030 *insn++ = BPF_ALU32_IMM(BPF_AND, tmp_reg, ~SKB_MONO_DELIVERY_TIME_MASK);
9031 *insn++ = BPF_STX_MEM(BPF_B, skb_reg, tmp_reg, PKT_VLAN_PRESENT_OFFSET);
9032 }
9033 #endif
9034
9035 /* <store>: skb->tstamp = tstamp */
9036 *insn++ = BPF_STX_MEM(BPF_DW, skb_reg, value_reg,
9037 offsetof(struct sk_buff, tstamp));
9038 return insn;
9039 }
9040
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)9041 static u32 bpf_convert_ctx_access(enum bpf_access_type type,
9042 const struct bpf_insn *si,
9043 struct bpf_insn *insn_buf,
9044 struct bpf_prog *prog, u32 *target_size)
9045 {
9046 struct bpf_insn *insn = insn_buf;
9047 int off;
9048
9049 switch (si->off) {
9050 case offsetof(struct __sk_buff, len):
9051 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9052 bpf_target_off(struct sk_buff, len, 4,
9053 target_size));
9054 break;
9055
9056 case offsetof(struct __sk_buff, protocol):
9057 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9058 bpf_target_off(struct sk_buff, protocol, 2,
9059 target_size));
9060 break;
9061
9062 case offsetof(struct __sk_buff, vlan_proto):
9063 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9064 bpf_target_off(struct sk_buff, vlan_proto, 2,
9065 target_size));
9066 break;
9067
9068 case offsetof(struct __sk_buff, priority):
9069 if (type == BPF_WRITE)
9070 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9071 bpf_target_off(struct sk_buff, priority, 4,
9072 target_size));
9073 else
9074 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9075 bpf_target_off(struct sk_buff, priority, 4,
9076 target_size));
9077 break;
9078
9079 case offsetof(struct __sk_buff, ingress_ifindex):
9080 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9081 bpf_target_off(struct sk_buff, skb_iif, 4,
9082 target_size));
9083 break;
9084
9085 case offsetof(struct __sk_buff, ifindex):
9086 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
9087 si->dst_reg, si->src_reg,
9088 offsetof(struct sk_buff, dev));
9089 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
9090 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9091 bpf_target_off(struct net_device, ifindex, 4,
9092 target_size));
9093 break;
9094
9095 case offsetof(struct __sk_buff, hash):
9096 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9097 bpf_target_off(struct sk_buff, hash, 4,
9098 target_size));
9099 break;
9100
9101 case offsetof(struct __sk_buff, mark):
9102 if (type == BPF_WRITE)
9103 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9104 bpf_target_off(struct sk_buff, mark, 4,
9105 target_size));
9106 else
9107 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9108 bpf_target_off(struct sk_buff, mark, 4,
9109 target_size));
9110 break;
9111
9112 case offsetof(struct __sk_buff, pkt_type):
9113 *target_size = 1;
9114 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
9115 PKT_TYPE_OFFSET);
9116 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
9117 #ifdef __BIG_ENDIAN_BITFIELD
9118 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
9119 #endif
9120 break;
9121
9122 case offsetof(struct __sk_buff, queue_mapping):
9123 if (type == BPF_WRITE) {
9124 *insn++ = BPF_JMP_IMM(BPF_JGE, si->src_reg, NO_QUEUE_MAPPING, 1);
9125 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
9126 bpf_target_off(struct sk_buff,
9127 queue_mapping,
9128 2, target_size));
9129 } else {
9130 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9131 bpf_target_off(struct sk_buff,
9132 queue_mapping,
9133 2, target_size));
9134 }
9135 break;
9136
9137 case offsetof(struct __sk_buff, vlan_present):
9138 *target_size = 1;
9139 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
9140 PKT_VLAN_PRESENT_OFFSET);
9141 if (PKT_VLAN_PRESENT_BIT)
9142 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, PKT_VLAN_PRESENT_BIT);
9143 if (PKT_VLAN_PRESENT_BIT < 7)
9144 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
9145 break;
9146
9147 case offsetof(struct __sk_buff, vlan_tci):
9148 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9149 bpf_target_off(struct sk_buff, vlan_tci, 2,
9150 target_size));
9151 break;
9152
9153 case offsetof(struct __sk_buff, cb[0]) ...
9154 offsetofend(struct __sk_buff, cb[4]) - 1:
9155 BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, data) < 20);
9156 BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
9157 offsetof(struct qdisc_skb_cb, data)) %
9158 sizeof(__u64));
9159
9160 prog->cb_access = 1;
9161 off = si->off;
9162 off -= offsetof(struct __sk_buff, cb[0]);
9163 off += offsetof(struct sk_buff, cb);
9164 off += offsetof(struct qdisc_skb_cb, data);
9165 if (type == BPF_WRITE)
9166 *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
9167 si->src_reg, off);
9168 else
9169 *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
9170 si->src_reg, off);
9171 break;
9172
9173 case offsetof(struct __sk_buff, tc_classid):
9174 BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, tc_classid) != 2);
9175
9176 off = si->off;
9177 off -= offsetof(struct __sk_buff, tc_classid);
9178 off += offsetof(struct sk_buff, cb);
9179 off += offsetof(struct qdisc_skb_cb, tc_classid);
9180 *target_size = 2;
9181 if (type == BPF_WRITE)
9182 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg,
9183 si->src_reg, off);
9184 else
9185 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
9186 si->src_reg, off);
9187 break;
9188
9189 case offsetof(struct __sk_buff, data):
9190 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
9191 si->dst_reg, si->src_reg,
9192 offsetof(struct sk_buff, data));
9193 break;
9194
9195 case offsetof(struct __sk_buff, data_meta):
9196 off = si->off;
9197 off -= offsetof(struct __sk_buff, data_meta);
9198 off += offsetof(struct sk_buff, cb);
9199 off += offsetof(struct bpf_skb_data_end, data_meta);
9200 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
9201 si->src_reg, off);
9202 break;
9203
9204 case offsetof(struct __sk_buff, data_end):
9205 off = si->off;
9206 off -= offsetof(struct __sk_buff, data_end);
9207 off += offsetof(struct sk_buff, cb);
9208 off += offsetof(struct bpf_skb_data_end, data_end);
9209 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
9210 si->src_reg, off);
9211 break;
9212
9213 case offsetof(struct __sk_buff, tc_index):
9214 #ifdef CONFIG_NET_SCHED
9215 if (type == BPF_WRITE)
9216 *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
9217 bpf_target_off(struct sk_buff, tc_index, 2,
9218 target_size));
9219 else
9220 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
9221 bpf_target_off(struct sk_buff, tc_index, 2,
9222 target_size));
9223 #else
9224 *target_size = 2;
9225 if (type == BPF_WRITE)
9226 *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
9227 else
9228 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9229 #endif
9230 break;
9231
9232 case offsetof(struct __sk_buff, napi_id):
9233 #if defined(CONFIG_NET_RX_BUSY_POLL)
9234 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9235 bpf_target_off(struct sk_buff, napi_id, 4,
9236 target_size));
9237 *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
9238 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9239 #else
9240 *target_size = 4;
9241 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
9242 #endif
9243 break;
9244 case offsetof(struct __sk_buff, family):
9245 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
9246
9247 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9248 si->dst_reg, si->src_reg,
9249 offsetof(struct sk_buff, sk));
9250 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9251 bpf_target_off(struct sock_common,
9252 skc_family,
9253 2, target_size));
9254 break;
9255 case offsetof(struct __sk_buff, remote_ip4):
9256 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
9257
9258 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9259 si->dst_reg, si->src_reg,
9260 offsetof(struct sk_buff, sk));
9261 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9262 bpf_target_off(struct sock_common,
9263 skc_daddr,
9264 4, target_size));
9265 break;
9266 case offsetof(struct __sk_buff, local_ip4):
9267 BUILD_BUG_ON(sizeof_field(struct sock_common,
9268 skc_rcv_saddr) != 4);
9269
9270 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9271 si->dst_reg, si->src_reg,
9272 offsetof(struct sk_buff, sk));
9273 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9274 bpf_target_off(struct sock_common,
9275 skc_rcv_saddr,
9276 4, target_size));
9277 break;
9278 case offsetof(struct __sk_buff, remote_ip6[0]) ...
9279 offsetof(struct __sk_buff, remote_ip6[3]):
9280 #if IS_ENABLED(CONFIG_IPV6)
9281 BUILD_BUG_ON(sizeof_field(struct sock_common,
9282 skc_v6_daddr.s6_addr32[0]) != 4);
9283
9284 off = si->off;
9285 off -= offsetof(struct __sk_buff, remote_ip6[0]);
9286
9287 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9288 si->dst_reg, si->src_reg,
9289 offsetof(struct sk_buff, sk));
9290 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9291 offsetof(struct sock_common,
9292 skc_v6_daddr.s6_addr32[0]) +
9293 off);
9294 #else
9295 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9296 #endif
9297 break;
9298 case offsetof(struct __sk_buff, local_ip6[0]) ...
9299 offsetof(struct __sk_buff, local_ip6[3]):
9300 #if IS_ENABLED(CONFIG_IPV6)
9301 BUILD_BUG_ON(sizeof_field(struct sock_common,
9302 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
9303
9304 off = si->off;
9305 off -= offsetof(struct __sk_buff, local_ip6[0]);
9306
9307 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9308 si->dst_reg, si->src_reg,
9309 offsetof(struct sk_buff, sk));
9310 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9311 offsetof(struct sock_common,
9312 skc_v6_rcv_saddr.s6_addr32[0]) +
9313 off);
9314 #else
9315 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9316 #endif
9317 break;
9318
9319 case offsetof(struct __sk_buff, remote_port):
9320 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
9321
9322 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9323 si->dst_reg, si->src_reg,
9324 offsetof(struct sk_buff, sk));
9325 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9326 bpf_target_off(struct sock_common,
9327 skc_dport,
9328 2, target_size));
9329 #ifndef __BIG_ENDIAN_BITFIELD
9330 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
9331 #endif
9332 break;
9333
9334 case offsetof(struct __sk_buff, local_port):
9335 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
9336
9337 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9338 si->dst_reg, si->src_reg,
9339 offsetof(struct sk_buff, sk));
9340 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9341 bpf_target_off(struct sock_common,
9342 skc_num, 2, target_size));
9343 break;
9344
9345 case offsetof(struct __sk_buff, tstamp):
9346 BUILD_BUG_ON(sizeof_field(struct sk_buff, tstamp) != 8);
9347
9348 if (type == BPF_WRITE)
9349 insn = bpf_convert_tstamp_write(prog, si, insn);
9350 else
9351 insn = bpf_convert_tstamp_read(prog, si, insn);
9352 break;
9353
9354 case offsetof(struct __sk_buff, tstamp_type):
9355 insn = bpf_convert_tstamp_type_read(si, insn);
9356 break;
9357
9358 case offsetof(struct __sk_buff, gso_segs):
9359 insn = bpf_convert_shinfo_access(si, insn);
9360 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_segs),
9361 si->dst_reg, si->dst_reg,
9362 bpf_target_off(struct skb_shared_info,
9363 gso_segs, 2,
9364 target_size));
9365 break;
9366 case offsetof(struct __sk_buff, gso_size):
9367 insn = bpf_convert_shinfo_access(si, insn);
9368 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct skb_shared_info, gso_size),
9369 si->dst_reg, si->dst_reg,
9370 bpf_target_off(struct skb_shared_info,
9371 gso_size, 2,
9372 target_size));
9373 break;
9374 case offsetof(struct __sk_buff, wire_len):
9375 BUILD_BUG_ON(sizeof_field(struct qdisc_skb_cb, pkt_len) != 4);
9376
9377 off = si->off;
9378 off -= offsetof(struct __sk_buff, wire_len);
9379 off += offsetof(struct sk_buff, cb);
9380 off += offsetof(struct qdisc_skb_cb, pkt_len);
9381 *target_size = 4;
9382 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, off);
9383 break;
9384
9385 case offsetof(struct __sk_buff, sk):
9386 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
9387 si->dst_reg, si->src_reg,
9388 offsetof(struct sk_buff, sk));
9389 break;
9390 case offsetof(struct __sk_buff, hwtstamp):
9391 BUILD_BUG_ON(sizeof_field(struct skb_shared_hwtstamps, hwtstamp) != 8);
9392 BUILD_BUG_ON(offsetof(struct skb_shared_hwtstamps, hwtstamp) != 0);
9393
9394 insn = bpf_convert_shinfo_access(si, insn);
9395 *insn++ = BPF_LDX_MEM(BPF_DW,
9396 si->dst_reg, si->dst_reg,
9397 bpf_target_off(struct skb_shared_info,
9398 hwtstamps, 8,
9399 target_size));
9400 break;
9401 }
9402
9403 return insn - insn_buf;
9404 }
9405
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)9406 u32 bpf_sock_convert_ctx_access(enum bpf_access_type type,
9407 const struct bpf_insn *si,
9408 struct bpf_insn *insn_buf,
9409 struct bpf_prog *prog, u32 *target_size)
9410 {
9411 struct bpf_insn *insn = insn_buf;
9412 int off;
9413
9414 switch (si->off) {
9415 case offsetof(struct bpf_sock, bound_dev_if):
9416 BUILD_BUG_ON(sizeof_field(struct sock, sk_bound_dev_if) != 4);
9417
9418 if (type == BPF_WRITE)
9419 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9420 offsetof(struct sock, sk_bound_dev_if));
9421 else
9422 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9423 offsetof(struct sock, sk_bound_dev_if));
9424 break;
9425
9426 case offsetof(struct bpf_sock, mark):
9427 BUILD_BUG_ON(sizeof_field(struct sock, sk_mark) != 4);
9428
9429 if (type == BPF_WRITE)
9430 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9431 offsetof(struct sock, sk_mark));
9432 else
9433 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9434 offsetof(struct sock, sk_mark));
9435 break;
9436
9437 case offsetof(struct bpf_sock, priority):
9438 BUILD_BUG_ON(sizeof_field(struct sock, sk_priority) != 4);
9439
9440 if (type == BPF_WRITE)
9441 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9442 offsetof(struct sock, sk_priority));
9443 else
9444 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9445 offsetof(struct sock, sk_priority));
9446 break;
9447
9448 case offsetof(struct bpf_sock, family):
9449 *insn++ = BPF_LDX_MEM(
9450 BPF_FIELD_SIZEOF(struct sock_common, skc_family),
9451 si->dst_reg, si->src_reg,
9452 bpf_target_off(struct sock_common,
9453 skc_family,
9454 sizeof_field(struct sock_common,
9455 skc_family),
9456 target_size));
9457 break;
9458
9459 case offsetof(struct bpf_sock, type):
9460 *insn++ = BPF_LDX_MEM(
9461 BPF_FIELD_SIZEOF(struct sock, sk_type),
9462 si->dst_reg, si->src_reg,
9463 bpf_target_off(struct sock, sk_type,
9464 sizeof_field(struct sock, sk_type),
9465 target_size));
9466 break;
9467
9468 case offsetof(struct bpf_sock, protocol):
9469 *insn++ = BPF_LDX_MEM(
9470 BPF_FIELD_SIZEOF(struct sock, sk_protocol),
9471 si->dst_reg, si->src_reg,
9472 bpf_target_off(struct sock, sk_protocol,
9473 sizeof_field(struct sock, sk_protocol),
9474 target_size));
9475 break;
9476
9477 case offsetof(struct bpf_sock, src_ip4):
9478 *insn++ = BPF_LDX_MEM(
9479 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9480 bpf_target_off(struct sock_common, skc_rcv_saddr,
9481 sizeof_field(struct sock_common,
9482 skc_rcv_saddr),
9483 target_size));
9484 break;
9485
9486 case offsetof(struct bpf_sock, dst_ip4):
9487 *insn++ = BPF_LDX_MEM(
9488 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9489 bpf_target_off(struct sock_common, skc_daddr,
9490 sizeof_field(struct sock_common,
9491 skc_daddr),
9492 target_size));
9493 break;
9494
9495 case bpf_ctx_range_till(struct bpf_sock, src_ip6[0], src_ip6[3]):
9496 #if IS_ENABLED(CONFIG_IPV6)
9497 off = si->off;
9498 off -= offsetof(struct bpf_sock, src_ip6[0]);
9499 *insn++ = BPF_LDX_MEM(
9500 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9501 bpf_target_off(
9502 struct sock_common,
9503 skc_v6_rcv_saddr.s6_addr32[0],
9504 sizeof_field(struct sock_common,
9505 skc_v6_rcv_saddr.s6_addr32[0]),
9506 target_size) + off);
9507 #else
9508 (void)off;
9509 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9510 #endif
9511 break;
9512
9513 case bpf_ctx_range_till(struct bpf_sock, dst_ip6[0], dst_ip6[3]):
9514 #if IS_ENABLED(CONFIG_IPV6)
9515 off = si->off;
9516 off -= offsetof(struct bpf_sock, dst_ip6[0]);
9517 *insn++ = BPF_LDX_MEM(
9518 BPF_SIZE(si->code), si->dst_reg, si->src_reg,
9519 bpf_target_off(struct sock_common,
9520 skc_v6_daddr.s6_addr32[0],
9521 sizeof_field(struct sock_common,
9522 skc_v6_daddr.s6_addr32[0]),
9523 target_size) + off);
9524 #else
9525 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
9526 *target_size = 4;
9527 #endif
9528 break;
9529
9530 case offsetof(struct bpf_sock, src_port):
9531 *insn++ = BPF_LDX_MEM(
9532 BPF_FIELD_SIZEOF(struct sock_common, skc_num),
9533 si->dst_reg, si->src_reg,
9534 bpf_target_off(struct sock_common, skc_num,
9535 sizeof_field(struct sock_common,
9536 skc_num),
9537 target_size));
9538 break;
9539
9540 case offsetof(struct bpf_sock, dst_port):
9541 *insn++ = BPF_LDX_MEM(
9542 BPF_FIELD_SIZEOF(struct sock_common, skc_dport),
9543 si->dst_reg, si->src_reg,
9544 bpf_target_off(struct sock_common, skc_dport,
9545 sizeof_field(struct sock_common,
9546 skc_dport),
9547 target_size));
9548 break;
9549
9550 case offsetof(struct bpf_sock, state):
9551 *insn++ = BPF_LDX_MEM(
9552 BPF_FIELD_SIZEOF(struct sock_common, skc_state),
9553 si->dst_reg, si->src_reg,
9554 bpf_target_off(struct sock_common, skc_state,
9555 sizeof_field(struct sock_common,
9556 skc_state),
9557 target_size));
9558 break;
9559 case offsetof(struct bpf_sock, rx_queue_mapping):
9560 #ifdef CONFIG_SOCK_RX_QUEUE_MAPPING
9561 *insn++ = BPF_LDX_MEM(
9562 BPF_FIELD_SIZEOF(struct sock, sk_rx_queue_mapping),
9563 si->dst_reg, si->src_reg,
9564 bpf_target_off(struct sock, sk_rx_queue_mapping,
9565 sizeof_field(struct sock,
9566 sk_rx_queue_mapping),
9567 target_size));
9568 *insn++ = BPF_JMP_IMM(BPF_JNE, si->dst_reg, NO_QUEUE_MAPPING,
9569 1);
9570 *insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
9571 #else
9572 *insn++ = BPF_MOV64_IMM(si->dst_reg, -1);
9573 *target_size = 2;
9574 #endif
9575 break;
9576 }
9577
9578 return insn - insn_buf;
9579 }
9580
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)9581 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
9582 const struct bpf_insn *si,
9583 struct bpf_insn *insn_buf,
9584 struct bpf_prog *prog, u32 *target_size)
9585 {
9586 struct bpf_insn *insn = insn_buf;
9587
9588 switch (si->off) {
9589 case offsetof(struct __sk_buff, ifindex):
9590 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
9591 si->dst_reg, si->src_reg,
9592 offsetof(struct sk_buff, dev));
9593 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9594 bpf_target_off(struct net_device, ifindex, 4,
9595 target_size));
9596 break;
9597 default:
9598 return bpf_convert_ctx_access(type, si, insn_buf, prog,
9599 target_size);
9600 }
9601
9602 return insn - insn_buf;
9603 }
9604
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)9605 static u32 xdp_convert_ctx_access(enum bpf_access_type type,
9606 const struct bpf_insn *si,
9607 struct bpf_insn *insn_buf,
9608 struct bpf_prog *prog, u32 *target_size)
9609 {
9610 struct bpf_insn *insn = insn_buf;
9611
9612 switch (si->off) {
9613 case offsetof(struct xdp_md, data):
9614 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
9615 si->dst_reg, si->src_reg,
9616 offsetof(struct xdp_buff, data));
9617 break;
9618 case offsetof(struct xdp_md, data_meta):
9619 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
9620 si->dst_reg, si->src_reg,
9621 offsetof(struct xdp_buff, data_meta));
9622 break;
9623 case offsetof(struct xdp_md, data_end):
9624 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
9625 si->dst_reg, si->src_reg,
9626 offsetof(struct xdp_buff, data_end));
9627 break;
9628 case offsetof(struct xdp_md, ingress_ifindex):
9629 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
9630 si->dst_reg, si->src_reg,
9631 offsetof(struct xdp_buff, rxq));
9632 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_rxq_info, dev),
9633 si->dst_reg, si->dst_reg,
9634 offsetof(struct xdp_rxq_info, dev));
9635 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9636 offsetof(struct net_device, ifindex));
9637 break;
9638 case offsetof(struct xdp_md, rx_queue_index):
9639 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, rxq),
9640 si->dst_reg, si->src_reg,
9641 offsetof(struct xdp_buff, rxq));
9642 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9643 offsetof(struct xdp_rxq_info,
9644 queue_index));
9645 break;
9646 case offsetof(struct xdp_md, egress_ifindex):
9647 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, txq),
9648 si->dst_reg, si->src_reg,
9649 offsetof(struct xdp_buff, txq));
9650 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_txq_info, dev),
9651 si->dst_reg, si->dst_reg,
9652 offsetof(struct xdp_txq_info, dev));
9653 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
9654 offsetof(struct net_device, ifindex));
9655 break;
9656 }
9657
9658 return insn - insn_buf;
9659 }
9660
9661 /* SOCK_ADDR_LOAD_NESTED_FIELD() loads Nested Field S.F.NF where S is type of
9662 * context Structure, F is Field in context structure that contains a pointer
9663 * to Nested Structure of type NS that has the field NF.
9664 *
9665 * SIZE encodes the load size (BPF_B, BPF_H, etc). It's up to caller to make
9666 * sure that SIZE is not greater than actual size of S.F.NF.
9667 *
9668 * If offset OFF is provided, the load happens from that offset relative to
9669 * offset of NF.
9670 */
9671 #define SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF) \
9672 do { \
9673 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), si->dst_reg, \
9674 si->src_reg, offsetof(S, F)); \
9675 *insn++ = BPF_LDX_MEM( \
9676 SIZE, si->dst_reg, si->dst_reg, \
9677 bpf_target_off(NS, NF, sizeof_field(NS, NF), \
9678 target_size) \
9679 + OFF); \
9680 } while (0)
9681
9682 #define SOCK_ADDR_LOAD_NESTED_FIELD(S, NS, F, NF) \
9683 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, \
9684 BPF_FIELD_SIZEOF(NS, NF), 0)
9685
9686 /* SOCK_ADDR_STORE_NESTED_FIELD_OFF() has semantic similar to
9687 * SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF() but for store operation.
9688 *
9689 * In addition it uses Temporary Field TF (member of struct S) as the 3rd
9690 * "register" since two registers available in convert_ctx_access are not
9691 * enough: we can't override neither SRC, since it contains value to store, nor
9692 * DST since it contains pointer to context that may be used by later
9693 * instructions. But we need a temporary place to save pointer to nested
9694 * structure whose field we want to store to.
9695 */
9696 #define SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE, OFF, TF) \
9697 do { \
9698 int tmp_reg = BPF_REG_9; \
9699 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \
9700 --tmp_reg; \
9701 if (si->src_reg == tmp_reg || si->dst_reg == tmp_reg) \
9702 --tmp_reg; \
9703 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, tmp_reg, \
9704 offsetof(S, TF)); \
9705 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(S, F), tmp_reg, \
9706 si->dst_reg, offsetof(S, F)); \
9707 *insn++ = BPF_STX_MEM(SIZE, tmp_reg, si->src_reg, \
9708 bpf_target_off(NS, NF, sizeof_field(NS, NF), \
9709 target_size) \
9710 + OFF); \
9711 *insn++ = BPF_LDX_MEM(BPF_DW, tmp_reg, si->dst_reg, \
9712 offsetof(S, TF)); \
9713 } while (0)
9714
9715 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(S, NS, F, NF, SIZE, OFF, \
9716 TF) \
9717 do { \
9718 if (type == BPF_WRITE) { \
9719 SOCK_ADDR_STORE_NESTED_FIELD_OFF(S, NS, F, NF, SIZE, \
9720 OFF, TF); \
9721 } else { \
9722 SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF( \
9723 S, NS, F, NF, SIZE, OFF); \
9724 } \
9725 } while (0)
9726
9727 #define SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD(S, NS, F, NF, TF) \
9728 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF( \
9729 S, NS, F, NF, BPF_FIELD_SIZEOF(NS, NF), 0, TF)
9730
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)9731 static u32 sock_addr_convert_ctx_access(enum bpf_access_type type,
9732 const struct bpf_insn *si,
9733 struct bpf_insn *insn_buf,
9734 struct bpf_prog *prog, u32 *target_size)
9735 {
9736 int off, port_size = sizeof_field(struct sockaddr_in6, sin6_port);
9737 struct bpf_insn *insn = insn_buf;
9738
9739 switch (si->off) {
9740 case offsetof(struct bpf_sock_addr, user_family):
9741 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9742 struct sockaddr, uaddr, sa_family);
9743 break;
9744
9745 case offsetof(struct bpf_sock_addr, user_ip4):
9746 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9747 struct bpf_sock_addr_kern, struct sockaddr_in, uaddr,
9748 sin_addr, BPF_SIZE(si->code), 0, tmp_reg);
9749 break;
9750
9751 case bpf_ctx_range_till(struct bpf_sock_addr, user_ip6[0], user_ip6[3]):
9752 off = si->off;
9753 off -= offsetof(struct bpf_sock_addr, user_ip6[0]);
9754 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9755 struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
9756 sin6_addr.s6_addr32[0], BPF_SIZE(si->code), off,
9757 tmp_reg);
9758 break;
9759
9760 case offsetof(struct bpf_sock_addr, user_port):
9761 /* To get port we need to know sa_family first and then treat
9762 * sockaddr as either sockaddr_in or sockaddr_in6.
9763 * Though we can simplify since port field has same offset and
9764 * size in both structures.
9765 * Here we check this invariant and use just one of the
9766 * structures if it's true.
9767 */
9768 BUILD_BUG_ON(offsetof(struct sockaddr_in, sin_port) !=
9769 offsetof(struct sockaddr_in6, sin6_port));
9770 BUILD_BUG_ON(sizeof_field(struct sockaddr_in, sin_port) !=
9771 sizeof_field(struct sockaddr_in6, sin6_port));
9772 /* Account for sin6_port being smaller than user_port. */
9773 port_size = min(port_size, BPF_LDST_BYTES(si));
9774 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9775 struct bpf_sock_addr_kern, struct sockaddr_in6, uaddr,
9776 sin6_port, bytes_to_bpf_size(port_size), 0, tmp_reg);
9777 break;
9778
9779 case offsetof(struct bpf_sock_addr, family):
9780 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9781 struct sock, sk, sk_family);
9782 break;
9783
9784 case offsetof(struct bpf_sock_addr, type):
9785 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9786 struct sock, sk, sk_type);
9787 break;
9788
9789 case offsetof(struct bpf_sock_addr, protocol):
9790 SOCK_ADDR_LOAD_NESTED_FIELD(struct bpf_sock_addr_kern,
9791 struct sock, sk, sk_protocol);
9792 break;
9793
9794 case offsetof(struct bpf_sock_addr, msg_src_ip4):
9795 /* Treat t_ctx as struct in_addr for msg_src_ip4. */
9796 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9797 struct bpf_sock_addr_kern, struct in_addr, t_ctx,
9798 s_addr, BPF_SIZE(si->code), 0, tmp_reg);
9799 break;
9800
9801 case bpf_ctx_range_till(struct bpf_sock_addr, msg_src_ip6[0],
9802 msg_src_ip6[3]):
9803 off = si->off;
9804 off -= offsetof(struct bpf_sock_addr, msg_src_ip6[0]);
9805 /* Treat t_ctx as struct in6_addr for msg_src_ip6. */
9806 SOCK_ADDR_LOAD_OR_STORE_NESTED_FIELD_SIZE_OFF(
9807 struct bpf_sock_addr_kern, struct in6_addr, t_ctx,
9808 s6_addr32[0], BPF_SIZE(si->code), off, tmp_reg);
9809 break;
9810 case offsetof(struct bpf_sock_addr, sk):
9811 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_addr_kern, sk),
9812 si->dst_reg, si->src_reg,
9813 offsetof(struct bpf_sock_addr_kern, sk));
9814 break;
9815 }
9816
9817 return insn - insn_buf;
9818 }
9819
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)9820 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
9821 const struct bpf_insn *si,
9822 struct bpf_insn *insn_buf,
9823 struct bpf_prog *prog,
9824 u32 *target_size)
9825 {
9826 struct bpf_insn *insn = insn_buf;
9827 int off;
9828
9829 /* Helper macro for adding read access to tcp_sock or sock fields. */
9830 #define SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \
9831 do { \
9832 int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 2; \
9833 BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) > \
9834 sizeof_field(struct bpf_sock_ops, BPF_FIELD)); \
9835 if (si->dst_reg == reg || si->src_reg == reg) \
9836 reg--; \
9837 if (si->dst_reg == reg || si->src_reg == reg) \
9838 reg--; \
9839 if (si->dst_reg == si->src_reg) { \
9840 *insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg, \
9841 offsetof(struct bpf_sock_ops_kern, \
9842 temp)); \
9843 fullsock_reg = reg; \
9844 jmp += 2; \
9845 } \
9846 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9847 struct bpf_sock_ops_kern, \
9848 is_fullsock), \
9849 fullsock_reg, si->src_reg, \
9850 offsetof(struct bpf_sock_ops_kern, \
9851 is_fullsock)); \
9852 *insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp); \
9853 if (si->dst_reg == si->src_reg) \
9854 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg, \
9855 offsetof(struct bpf_sock_ops_kern, \
9856 temp)); \
9857 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9858 struct bpf_sock_ops_kern, sk),\
9859 si->dst_reg, si->src_reg, \
9860 offsetof(struct bpf_sock_ops_kern, sk));\
9861 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(OBJ, \
9862 OBJ_FIELD), \
9863 si->dst_reg, si->dst_reg, \
9864 offsetof(OBJ, OBJ_FIELD)); \
9865 if (si->dst_reg == si->src_reg) { \
9866 *insn++ = BPF_JMP_A(1); \
9867 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg, \
9868 offsetof(struct bpf_sock_ops_kern, \
9869 temp)); \
9870 } \
9871 } while (0)
9872
9873 #define SOCK_OPS_GET_SK() \
9874 do { \
9875 int fullsock_reg = si->dst_reg, reg = BPF_REG_9, jmp = 1; \
9876 if (si->dst_reg == reg || si->src_reg == reg) \
9877 reg--; \
9878 if (si->dst_reg == reg || si->src_reg == reg) \
9879 reg--; \
9880 if (si->dst_reg == si->src_reg) { \
9881 *insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg, \
9882 offsetof(struct bpf_sock_ops_kern, \
9883 temp)); \
9884 fullsock_reg = reg; \
9885 jmp += 2; \
9886 } \
9887 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9888 struct bpf_sock_ops_kern, \
9889 is_fullsock), \
9890 fullsock_reg, si->src_reg, \
9891 offsetof(struct bpf_sock_ops_kern, \
9892 is_fullsock)); \
9893 *insn++ = BPF_JMP_IMM(BPF_JEQ, fullsock_reg, 0, jmp); \
9894 if (si->dst_reg == si->src_reg) \
9895 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg, \
9896 offsetof(struct bpf_sock_ops_kern, \
9897 temp)); \
9898 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9899 struct bpf_sock_ops_kern, sk),\
9900 si->dst_reg, si->src_reg, \
9901 offsetof(struct bpf_sock_ops_kern, sk));\
9902 if (si->dst_reg == si->src_reg) { \
9903 *insn++ = BPF_JMP_A(1); \
9904 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->src_reg, \
9905 offsetof(struct bpf_sock_ops_kern, \
9906 temp)); \
9907 } \
9908 } while (0)
9909
9910 #define SOCK_OPS_GET_TCP_SOCK_FIELD(FIELD) \
9911 SOCK_OPS_GET_FIELD(FIELD, FIELD, struct tcp_sock)
9912
9913 /* Helper macro for adding write access to tcp_sock or sock fields.
9914 * The macro is called with two registers, dst_reg which contains a pointer
9915 * to ctx (context) and src_reg which contains the value that should be
9916 * stored. However, we need an additional register since we cannot overwrite
9917 * dst_reg because it may be used later in the program.
9918 * Instead we "borrow" one of the other register. We first save its value
9919 * into a new (temp) field in bpf_sock_ops_kern, use it, and then restore
9920 * it at the end of the macro.
9921 */
9922 #define SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ) \
9923 do { \
9924 int reg = BPF_REG_9; \
9925 BUILD_BUG_ON(sizeof_field(OBJ, OBJ_FIELD) > \
9926 sizeof_field(struct bpf_sock_ops, BPF_FIELD)); \
9927 if (si->dst_reg == reg || si->src_reg == reg) \
9928 reg--; \
9929 if (si->dst_reg == reg || si->src_reg == reg) \
9930 reg--; \
9931 *insn++ = BPF_STX_MEM(BPF_DW, si->dst_reg, reg, \
9932 offsetof(struct bpf_sock_ops_kern, \
9933 temp)); \
9934 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9935 struct bpf_sock_ops_kern, \
9936 is_fullsock), \
9937 reg, si->dst_reg, \
9938 offsetof(struct bpf_sock_ops_kern, \
9939 is_fullsock)); \
9940 *insn++ = BPF_JMP_IMM(BPF_JEQ, reg, 0, 2); \
9941 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF( \
9942 struct bpf_sock_ops_kern, sk),\
9943 reg, si->dst_reg, \
9944 offsetof(struct bpf_sock_ops_kern, sk));\
9945 *insn++ = BPF_STX_MEM(BPF_FIELD_SIZEOF(OBJ, OBJ_FIELD), \
9946 reg, si->src_reg, \
9947 offsetof(OBJ, OBJ_FIELD)); \
9948 *insn++ = BPF_LDX_MEM(BPF_DW, reg, si->dst_reg, \
9949 offsetof(struct bpf_sock_ops_kern, \
9950 temp)); \
9951 } while (0)
9952
9953 #define SOCK_OPS_GET_OR_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ, TYPE) \
9954 do { \
9955 if (TYPE == BPF_WRITE) \
9956 SOCK_OPS_SET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \
9957 else \
9958 SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ); \
9959 } while (0)
9960
9961 if (insn > insn_buf)
9962 return insn - insn_buf;
9963
9964 switch (si->off) {
9965 case offsetof(struct bpf_sock_ops, op):
9966 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
9967 op),
9968 si->dst_reg, si->src_reg,
9969 offsetof(struct bpf_sock_ops_kern, op));
9970 break;
9971
9972 case offsetof(struct bpf_sock_ops, replylong[0]) ...
9973 offsetof(struct bpf_sock_ops, replylong[3]):
9974 BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, reply) !=
9975 sizeof_field(struct bpf_sock_ops_kern, reply));
9976 BUILD_BUG_ON(sizeof_field(struct bpf_sock_ops, replylong) !=
9977 sizeof_field(struct bpf_sock_ops_kern, replylong));
9978 off = si->off;
9979 off -= offsetof(struct bpf_sock_ops, replylong[0]);
9980 off += offsetof(struct bpf_sock_ops_kern, replylong[0]);
9981 if (type == BPF_WRITE)
9982 *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
9983 off);
9984 else
9985 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
9986 off);
9987 break;
9988
9989 case offsetof(struct bpf_sock_ops, family):
9990 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
9991
9992 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
9993 struct bpf_sock_ops_kern, sk),
9994 si->dst_reg, si->src_reg,
9995 offsetof(struct bpf_sock_ops_kern, sk));
9996 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
9997 offsetof(struct sock_common, skc_family));
9998 break;
9999
10000 case offsetof(struct bpf_sock_ops, remote_ip4):
10001 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
10002
10003 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10004 struct bpf_sock_ops_kern, sk),
10005 si->dst_reg, si->src_reg,
10006 offsetof(struct bpf_sock_ops_kern, sk));
10007 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10008 offsetof(struct sock_common, skc_daddr));
10009 break;
10010
10011 case offsetof(struct bpf_sock_ops, local_ip4):
10012 BUILD_BUG_ON(sizeof_field(struct sock_common,
10013 skc_rcv_saddr) != 4);
10014
10015 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10016 struct bpf_sock_ops_kern, sk),
10017 si->dst_reg, si->src_reg,
10018 offsetof(struct bpf_sock_ops_kern, sk));
10019 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10020 offsetof(struct sock_common,
10021 skc_rcv_saddr));
10022 break;
10023
10024 case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
10025 offsetof(struct bpf_sock_ops, remote_ip6[3]):
10026 #if IS_ENABLED(CONFIG_IPV6)
10027 BUILD_BUG_ON(sizeof_field(struct sock_common,
10028 skc_v6_daddr.s6_addr32[0]) != 4);
10029
10030 off = si->off;
10031 off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
10032 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10033 struct bpf_sock_ops_kern, sk),
10034 si->dst_reg, si->src_reg,
10035 offsetof(struct bpf_sock_ops_kern, sk));
10036 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10037 offsetof(struct sock_common,
10038 skc_v6_daddr.s6_addr32[0]) +
10039 off);
10040 #else
10041 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10042 #endif
10043 break;
10044
10045 case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
10046 offsetof(struct bpf_sock_ops, local_ip6[3]):
10047 #if IS_ENABLED(CONFIG_IPV6)
10048 BUILD_BUG_ON(sizeof_field(struct sock_common,
10049 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
10050
10051 off = si->off;
10052 off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
10053 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10054 struct bpf_sock_ops_kern, sk),
10055 si->dst_reg, si->src_reg,
10056 offsetof(struct bpf_sock_ops_kern, sk));
10057 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10058 offsetof(struct sock_common,
10059 skc_v6_rcv_saddr.s6_addr32[0]) +
10060 off);
10061 #else
10062 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10063 #endif
10064 break;
10065
10066 case offsetof(struct bpf_sock_ops, remote_port):
10067 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
10068
10069 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10070 struct bpf_sock_ops_kern, sk),
10071 si->dst_reg, si->src_reg,
10072 offsetof(struct bpf_sock_ops_kern, sk));
10073 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10074 offsetof(struct sock_common, skc_dport));
10075 #ifndef __BIG_ENDIAN_BITFIELD
10076 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
10077 #endif
10078 break;
10079
10080 case offsetof(struct bpf_sock_ops, local_port):
10081 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
10082
10083 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10084 struct bpf_sock_ops_kern, sk),
10085 si->dst_reg, si->src_reg,
10086 offsetof(struct bpf_sock_ops_kern, sk));
10087 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10088 offsetof(struct sock_common, skc_num));
10089 break;
10090
10091 case offsetof(struct bpf_sock_ops, is_fullsock):
10092 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10093 struct bpf_sock_ops_kern,
10094 is_fullsock),
10095 si->dst_reg, si->src_reg,
10096 offsetof(struct bpf_sock_ops_kern,
10097 is_fullsock));
10098 break;
10099
10100 case offsetof(struct bpf_sock_ops, state):
10101 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_state) != 1);
10102
10103 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10104 struct bpf_sock_ops_kern, sk),
10105 si->dst_reg, si->src_reg,
10106 offsetof(struct bpf_sock_ops_kern, sk));
10107 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->dst_reg,
10108 offsetof(struct sock_common, skc_state));
10109 break;
10110
10111 case offsetof(struct bpf_sock_ops, rtt_min):
10112 BUILD_BUG_ON(sizeof_field(struct tcp_sock, rtt_min) !=
10113 sizeof(struct minmax));
10114 BUILD_BUG_ON(sizeof(struct minmax) <
10115 sizeof(struct minmax_sample));
10116
10117 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10118 struct bpf_sock_ops_kern, sk),
10119 si->dst_reg, si->src_reg,
10120 offsetof(struct bpf_sock_ops_kern, sk));
10121 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10122 offsetof(struct tcp_sock, rtt_min) +
10123 sizeof_field(struct minmax_sample, t));
10124 break;
10125
10126 case offsetof(struct bpf_sock_ops, bpf_sock_ops_cb_flags):
10127 SOCK_OPS_GET_FIELD(bpf_sock_ops_cb_flags, bpf_sock_ops_cb_flags,
10128 struct tcp_sock);
10129 break;
10130
10131 case offsetof(struct bpf_sock_ops, sk_txhash):
10132 SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash,
10133 struct sock, type);
10134 break;
10135 case offsetof(struct bpf_sock_ops, snd_cwnd):
10136 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_cwnd);
10137 break;
10138 case offsetof(struct bpf_sock_ops, srtt_us):
10139 SOCK_OPS_GET_TCP_SOCK_FIELD(srtt_us);
10140 break;
10141 case offsetof(struct bpf_sock_ops, snd_ssthresh):
10142 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_ssthresh);
10143 break;
10144 case offsetof(struct bpf_sock_ops, rcv_nxt):
10145 SOCK_OPS_GET_TCP_SOCK_FIELD(rcv_nxt);
10146 break;
10147 case offsetof(struct bpf_sock_ops, snd_nxt):
10148 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_nxt);
10149 break;
10150 case offsetof(struct bpf_sock_ops, snd_una):
10151 SOCK_OPS_GET_TCP_SOCK_FIELD(snd_una);
10152 break;
10153 case offsetof(struct bpf_sock_ops, mss_cache):
10154 SOCK_OPS_GET_TCP_SOCK_FIELD(mss_cache);
10155 break;
10156 case offsetof(struct bpf_sock_ops, ecn_flags):
10157 SOCK_OPS_GET_TCP_SOCK_FIELD(ecn_flags);
10158 break;
10159 case offsetof(struct bpf_sock_ops, rate_delivered):
10160 SOCK_OPS_GET_TCP_SOCK_FIELD(rate_delivered);
10161 break;
10162 case offsetof(struct bpf_sock_ops, rate_interval_us):
10163 SOCK_OPS_GET_TCP_SOCK_FIELD(rate_interval_us);
10164 break;
10165 case offsetof(struct bpf_sock_ops, packets_out):
10166 SOCK_OPS_GET_TCP_SOCK_FIELD(packets_out);
10167 break;
10168 case offsetof(struct bpf_sock_ops, retrans_out):
10169 SOCK_OPS_GET_TCP_SOCK_FIELD(retrans_out);
10170 break;
10171 case offsetof(struct bpf_sock_ops, total_retrans):
10172 SOCK_OPS_GET_TCP_SOCK_FIELD(total_retrans);
10173 break;
10174 case offsetof(struct bpf_sock_ops, segs_in):
10175 SOCK_OPS_GET_TCP_SOCK_FIELD(segs_in);
10176 break;
10177 case offsetof(struct bpf_sock_ops, data_segs_in):
10178 SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_in);
10179 break;
10180 case offsetof(struct bpf_sock_ops, segs_out):
10181 SOCK_OPS_GET_TCP_SOCK_FIELD(segs_out);
10182 break;
10183 case offsetof(struct bpf_sock_ops, data_segs_out):
10184 SOCK_OPS_GET_TCP_SOCK_FIELD(data_segs_out);
10185 break;
10186 case offsetof(struct bpf_sock_ops, lost_out):
10187 SOCK_OPS_GET_TCP_SOCK_FIELD(lost_out);
10188 break;
10189 case offsetof(struct bpf_sock_ops, sacked_out):
10190 SOCK_OPS_GET_TCP_SOCK_FIELD(sacked_out);
10191 break;
10192 case offsetof(struct bpf_sock_ops, bytes_received):
10193 SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_received);
10194 break;
10195 case offsetof(struct bpf_sock_ops, bytes_acked):
10196 SOCK_OPS_GET_TCP_SOCK_FIELD(bytes_acked);
10197 break;
10198 case offsetof(struct bpf_sock_ops, sk):
10199 SOCK_OPS_GET_SK();
10200 break;
10201 case offsetof(struct bpf_sock_ops, skb_data_end):
10202 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10203 skb_data_end),
10204 si->dst_reg, si->src_reg,
10205 offsetof(struct bpf_sock_ops_kern,
10206 skb_data_end));
10207 break;
10208 case offsetof(struct bpf_sock_ops, skb_data):
10209 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10210 skb),
10211 si->dst_reg, si->src_reg,
10212 offsetof(struct bpf_sock_ops_kern,
10213 skb));
10214 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10215 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
10216 si->dst_reg, si->dst_reg,
10217 offsetof(struct sk_buff, data));
10218 break;
10219 case offsetof(struct bpf_sock_ops, skb_len):
10220 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10221 skb),
10222 si->dst_reg, si->src_reg,
10223 offsetof(struct bpf_sock_ops_kern,
10224 skb));
10225 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10226 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
10227 si->dst_reg, si->dst_reg,
10228 offsetof(struct sk_buff, len));
10229 break;
10230 case offsetof(struct bpf_sock_ops, skb_tcp_flags):
10231 off = offsetof(struct sk_buff, cb);
10232 off += offsetof(struct tcp_skb_cb, tcp_flags);
10233 *target_size = sizeof_field(struct tcp_skb_cb, tcp_flags);
10234 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_sock_ops_kern,
10235 skb),
10236 si->dst_reg, si->src_reg,
10237 offsetof(struct bpf_sock_ops_kern,
10238 skb));
10239 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
10240 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct tcp_skb_cb,
10241 tcp_flags),
10242 si->dst_reg, si->dst_reg, off);
10243 break;
10244 }
10245 return insn - insn_buf;
10246 }
10247
10248 /* data_end = skb->data + skb_headlen() */
bpf_convert_data_end_access(const struct bpf_insn * si,struct bpf_insn * insn)10249 static struct bpf_insn *bpf_convert_data_end_access(const struct bpf_insn *si,
10250 struct bpf_insn *insn)
10251 {
10252 int reg;
10253 int temp_reg_off = offsetof(struct sk_buff, cb) +
10254 offsetof(struct sk_skb_cb, temp_reg);
10255
10256 if (si->src_reg == si->dst_reg) {
10257 /* We need an extra register, choose and save a register. */
10258 reg = BPF_REG_9;
10259 if (si->src_reg == reg || si->dst_reg == reg)
10260 reg--;
10261 if (si->src_reg == reg || si->dst_reg == reg)
10262 reg--;
10263 *insn++ = BPF_STX_MEM(BPF_DW, si->src_reg, reg, temp_reg_off);
10264 } else {
10265 reg = si->dst_reg;
10266 }
10267
10268 /* reg = skb->data */
10269 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
10270 reg, si->src_reg,
10271 offsetof(struct sk_buff, data));
10272 /* AX = skb->len */
10273 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, len),
10274 BPF_REG_AX, si->src_reg,
10275 offsetof(struct sk_buff, len));
10276 /* reg = skb->data + skb->len */
10277 *insn++ = BPF_ALU64_REG(BPF_ADD, reg, BPF_REG_AX);
10278 /* AX = skb->data_len */
10279 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data_len),
10280 BPF_REG_AX, si->src_reg,
10281 offsetof(struct sk_buff, data_len));
10282
10283 /* reg = skb->data + skb->len - skb->data_len */
10284 *insn++ = BPF_ALU64_REG(BPF_SUB, reg, BPF_REG_AX);
10285
10286 if (si->src_reg == si->dst_reg) {
10287 /* Restore the saved register */
10288 *insn++ = BPF_MOV64_REG(BPF_REG_AX, si->src_reg);
10289 *insn++ = BPF_MOV64_REG(si->dst_reg, reg);
10290 *insn++ = BPF_LDX_MEM(BPF_DW, reg, BPF_REG_AX, temp_reg_off);
10291 }
10292
10293 return insn;
10294 }
10295
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)10296 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
10297 const struct bpf_insn *si,
10298 struct bpf_insn *insn_buf,
10299 struct bpf_prog *prog, u32 *target_size)
10300 {
10301 struct bpf_insn *insn = insn_buf;
10302 int off;
10303
10304 switch (si->off) {
10305 case offsetof(struct __sk_buff, data_end):
10306 insn = bpf_convert_data_end_access(si, insn);
10307 break;
10308 case offsetof(struct __sk_buff, cb[0]) ...
10309 offsetofend(struct __sk_buff, cb[4]) - 1:
10310 BUILD_BUG_ON(sizeof_field(struct sk_skb_cb, data) < 20);
10311 BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
10312 offsetof(struct sk_skb_cb, data)) %
10313 sizeof(__u64));
10314
10315 prog->cb_access = 1;
10316 off = si->off;
10317 off -= offsetof(struct __sk_buff, cb[0]);
10318 off += offsetof(struct sk_buff, cb);
10319 off += offsetof(struct sk_skb_cb, data);
10320 if (type == BPF_WRITE)
10321 *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
10322 si->src_reg, off);
10323 else
10324 *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
10325 si->src_reg, off);
10326 break;
10327
10328
10329 default:
10330 return bpf_convert_ctx_access(type, si, insn_buf, prog,
10331 target_size);
10332 }
10333
10334 return insn - insn_buf;
10335 }
10336
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)10337 static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
10338 const struct bpf_insn *si,
10339 struct bpf_insn *insn_buf,
10340 struct bpf_prog *prog, u32 *target_size)
10341 {
10342 struct bpf_insn *insn = insn_buf;
10343 #if IS_ENABLED(CONFIG_IPV6)
10344 int off;
10345 #endif
10346
10347 /* convert ctx uses the fact sg element is first in struct */
10348 BUILD_BUG_ON(offsetof(struct sk_msg, sg) != 0);
10349
10350 switch (si->off) {
10351 case offsetof(struct sk_msg_md, data):
10352 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data),
10353 si->dst_reg, si->src_reg,
10354 offsetof(struct sk_msg, data));
10355 break;
10356 case offsetof(struct sk_msg_md, data_end):
10357 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, data_end),
10358 si->dst_reg, si->src_reg,
10359 offsetof(struct sk_msg, data_end));
10360 break;
10361 case offsetof(struct sk_msg_md, family):
10362 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_family) != 2);
10363
10364 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10365 struct sk_msg, sk),
10366 si->dst_reg, si->src_reg,
10367 offsetof(struct sk_msg, sk));
10368 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10369 offsetof(struct sock_common, skc_family));
10370 break;
10371
10372 case offsetof(struct sk_msg_md, remote_ip4):
10373 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_daddr) != 4);
10374
10375 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10376 struct sk_msg, sk),
10377 si->dst_reg, si->src_reg,
10378 offsetof(struct sk_msg, sk));
10379 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10380 offsetof(struct sock_common, skc_daddr));
10381 break;
10382
10383 case offsetof(struct sk_msg_md, local_ip4):
10384 BUILD_BUG_ON(sizeof_field(struct sock_common,
10385 skc_rcv_saddr) != 4);
10386
10387 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10388 struct sk_msg, sk),
10389 si->dst_reg, si->src_reg,
10390 offsetof(struct sk_msg, sk));
10391 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10392 offsetof(struct sock_common,
10393 skc_rcv_saddr));
10394 break;
10395
10396 case offsetof(struct sk_msg_md, remote_ip6[0]) ...
10397 offsetof(struct sk_msg_md, remote_ip6[3]):
10398 #if IS_ENABLED(CONFIG_IPV6)
10399 BUILD_BUG_ON(sizeof_field(struct sock_common,
10400 skc_v6_daddr.s6_addr32[0]) != 4);
10401
10402 off = si->off;
10403 off -= offsetof(struct sk_msg_md, remote_ip6[0]);
10404 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10405 struct sk_msg, sk),
10406 si->dst_reg, si->src_reg,
10407 offsetof(struct sk_msg, sk));
10408 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10409 offsetof(struct sock_common,
10410 skc_v6_daddr.s6_addr32[0]) +
10411 off);
10412 #else
10413 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10414 #endif
10415 break;
10416
10417 case offsetof(struct sk_msg_md, local_ip6[0]) ...
10418 offsetof(struct sk_msg_md, local_ip6[3]):
10419 #if IS_ENABLED(CONFIG_IPV6)
10420 BUILD_BUG_ON(sizeof_field(struct sock_common,
10421 skc_v6_rcv_saddr.s6_addr32[0]) != 4);
10422
10423 off = si->off;
10424 off -= offsetof(struct sk_msg_md, local_ip6[0]);
10425 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10426 struct sk_msg, sk),
10427 si->dst_reg, si->src_reg,
10428 offsetof(struct sk_msg, sk));
10429 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
10430 offsetof(struct sock_common,
10431 skc_v6_rcv_saddr.s6_addr32[0]) +
10432 off);
10433 #else
10434 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
10435 #endif
10436 break;
10437
10438 case offsetof(struct sk_msg_md, remote_port):
10439 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_dport) != 2);
10440
10441 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10442 struct sk_msg, sk),
10443 si->dst_reg, si->src_reg,
10444 offsetof(struct sk_msg, sk));
10445 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10446 offsetof(struct sock_common, skc_dport));
10447 #ifndef __BIG_ENDIAN_BITFIELD
10448 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
10449 #endif
10450 break;
10451
10452 case offsetof(struct sk_msg_md, local_port):
10453 BUILD_BUG_ON(sizeof_field(struct sock_common, skc_num) != 2);
10454
10455 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
10456 struct sk_msg, sk),
10457 si->dst_reg, si->src_reg,
10458 offsetof(struct sk_msg, sk));
10459 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
10460 offsetof(struct sock_common, skc_num));
10461 break;
10462
10463 case offsetof(struct sk_msg_md, size):
10464 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg_sg, size),
10465 si->dst_reg, si->src_reg,
10466 offsetof(struct sk_msg_sg, size));
10467 break;
10468
10469 case offsetof(struct sk_msg_md, sk):
10470 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_msg, sk),
10471 si->dst_reg, si->src_reg,
10472 offsetof(struct sk_msg, sk));
10473 break;
10474 }
10475
10476 return insn - insn_buf;
10477 }
10478
10479 const struct bpf_verifier_ops sk_filter_verifier_ops = {
10480 .get_func_proto = sk_filter_func_proto,
10481 .is_valid_access = sk_filter_is_valid_access,
10482 .convert_ctx_access = bpf_convert_ctx_access,
10483 .gen_ld_abs = bpf_gen_ld_abs,
10484 };
10485
10486 const struct bpf_prog_ops sk_filter_prog_ops = {
10487 .test_run = bpf_prog_test_run_skb,
10488 };
10489
10490 const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
10491 .get_func_proto = tc_cls_act_func_proto,
10492 .is_valid_access = tc_cls_act_is_valid_access,
10493 .convert_ctx_access = tc_cls_act_convert_ctx_access,
10494 .gen_prologue = tc_cls_act_prologue,
10495 .gen_ld_abs = bpf_gen_ld_abs,
10496 };
10497
10498 const struct bpf_prog_ops tc_cls_act_prog_ops = {
10499 .test_run = bpf_prog_test_run_skb,
10500 };
10501
10502 const struct bpf_verifier_ops xdp_verifier_ops = {
10503 .get_func_proto = xdp_func_proto,
10504 .is_valid_access = xdp_is_valid_access,
10505 .convert_ctx_access = xdp_convert_ctx_access,
10506 .gen_prologue = bpf_noop_prologue,
10507 };
10508
10509 const struct bpf_prog_ops xdp_prog_ops = {
10510 .test_run = bpf_prog_test_run_xdp,
10511 };
10512
10513 const struct bpf_verifier_ops cg_skb_verifier_ops = {
10514 .get_func_proto = cg_skb_func_proto,
10515 .is_valid_access = cg_skb_is_valid_access,
10516 .convert_ctx_access = bpf_convert_ctx_access,
10517 };
10518
10519 const struct bpf_prog_ops cg_skb_prog_ops = {
10520 .test_run = bpf_prog_test_run_skb,
10521 };
10522
10523 const struct bpf_verifier_ops lwt_in_verifier_ops = {
10524 .get_func_proto = lwt_in_func_proto,
10525 .is_valid_access = lwt_is_valid_access,
10526 .convert_ctx_access = bpf_convert_ctx_access,
10527 };
10528
10529 const struct bpf_prog_ops lwt_in_prog_ops = {
10530 .test_run = bpf_prog_test_run_skb,
10531 };
10532
10533 const struct bpf_verifier_ops lwt_out_verifier_ops = {
10534 .get_func_proto = lwt_out_func_proto,
10535 .is_valid_access = lwt_is_valid_access,
10536 .convert_ctx_access = bpf_convert_ctx_access,
10537 };
10538
10539 const struct bpf_prog_ops lwt_out_prog_ops = {
10540 .test_run = bpf_prog_test_run_skb,
10541 };
10542
10543 const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
10544 .get_func_proto = lwt_xmit_func_proto,
10545 .is_valid_access = lwt_is_valid_access,
10546 .convert_ctx_access = bpf_convert_ctx_access,
10547 .gen_prologue = tc_cls_act_prologue,
10548 };
10549
10550 const struct bpf_prog_ops lwt_xmit_prog_ops = {
10551 .test_run = bpf_prog_test_run_skb,
10552 };
10553
10554 const struct bpf_verifier_ops lwt_seg6local_verifier_ops = {
10555 .get_func_proto = lwt_seg6local_func_proto,
10556 .is_valid_access = lwt_is_valid_access,
10557 .convert_ctx_access = bpf_convert_ctx_access,
10558 };
10559
10560 const struct bpf_prog_ops lwt_seg6local_prog_ops = {
10561 .test_run = bpf_prog_test_run_skb,
10562 };
10563
10564 const struct bpf_verifier_ops cg_sock_verifier_ops = {
10565 .get_func_proto = sock_filter_func_proto,
10566 .is_valid_access = sock_filter_is_valid_access,
10567 .convert_ctx_access = bpf_sock_convert_ctx_access,
10568 };
10569
10570 const struct bpf_prog_ops cg_sock_prog_ops = {
10571 };
10572
10573 const struct bpf_verifier_ops cg_sock_addr_verifier_ops = {
10574 .get_func_proto = sock_addr_func_proto,
10575 .is_valid_access = sock_addr_is_valid_access,
10576 .convert_ctx_access = sock_addr_convert_ctx_access,
10577 };
10578
10579 const struct bpf_prog_ops cg_sock_addr_prog_ops = {
10580 };
10581
10582 const struct bpf_verifier_ops sock_ops_verifier_ops = {
10583 .get_func_proto = sock_ops_func_proto,
10584 .is_valid_access = sock_ops_is_valid_access,
10585 .convert_ctx_access = sock_ops_convert_ctx_access,
10586 };
10587
10588 const struct bpf_prog_ops sock_ops_prog_ops = {
10589 };
10590
10591 const struct bpf_verifier_ops sk_skb_verifier_ops = {
10592 .get_func_proto = sk_skb_func_proto,
10593 .is_valid_access = sk_skb_is_valid_access,
10594 .convert_ctx_access = sk_skb_convert_ctx_access,
10595 .gen_prologue = sk_skb_prologue,
10596 };
10597
10598 const struct bpf_prog_ops sk_skb_prog_ops = {
10599 };
10600
10601 const struct bpf_verifier_ops sk_msg_verifier_ops = {
10602 .get_func_proto = sk_msg_func_proto,
10603 .is_valid_access = sk_msg_is_valid_access,
10604 .convert_ctx_access = sk_msg_convert_ctx_access,
10605 .gen_prologue = bpf_noop_prologue,
10606 };
10607
10608 const struct bpf_prog_ops sk_msg_prog_ops = {
10609 };
10610
10611 const struct bpf_verifier_ops flow_dissector_verifier_ops = {
10612 .get_func_proto = flow_dissector_func_proto,
10613 .is_valid_access = flow_dissector_is_valid_access,
10614 .convert_ctx_access = flow_dissector_convert_ctx_access,
10615 };
10616
10617 const struct bpf_prog_ops flow_dissector_prog_ops = {
10618 .test_run = bpf_prog_test_run_flow_dissector,
10619 };
10620
sk_detach_filter(struct sock * sk)10621 int sk_detach_filter(struct sock *sk)
10622 {
10623 int ret = -ENOENT;
10624 struct sk_filter *filter;
10625
10626 if (sock_flag(sk, SOCK_FILTER_LOCKED))
10627 return -EPERM;
10628
10629 filter = rcu_dereference_protected(sk->sk_filter,
10630 lockdep_sock_is_held(sk));
10631 if (filter) {
10632 RCU_INIT_POINTER(sk->sk_filter, NULL);
10633 sk_filter_uncharge(sk, filter);
10634 ret = 0;
10635 }
10636
10637 return ret;
10638 }
10639 EXPORT_SYMBOL_GPL(sk_detach_filter);
10640
sk_get_filter(struct sock * sk,struct sock_filter __user * ubuf,unsigned int len)10641 int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf,
10642 unsigned int len)
10643 {
10644 struct sock_fprog_kern *fprog;
10645 struct sk_filter *filter;
10646 int ret = 0;
10647
10648 lock_sock(sk);
10649 filter = rcu_dereference_protected(sk->sk_filter,
10650 lockdep_sock_is_held(sk));
10651 if (!filter)
10652 goto out;
10653
10654 /* We're copying the filter that has been originally attached,
10655 * so no conversion/decode needed anymore. eBPF programs that
10656 * have no original program cannot be dumped through this.
10657 */
10658 ret = -EACCES;
10659 fprog = filter->prog->orig_prog;
10660 if (!fprog)
10661 goto out;
10662
10663 ret = fprog->len;
10664 if (!len)
10665 /* User space only enquires number of filter blocks. */
10666 goto out;
10667
10668 ret = -EINVAL;
10669 if (len < fprog->len)
10670 goto out;
10671
10672 ret = -EFAULT;
10673 if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog)))
10674 goto out;
10675
10676 /* Instead of bytes, the API requests to return the number
10677 * of filter blocks.
10678 */
10679 ret = fprog->len;
10680 out:
10681 release_sock(sk);
10682 return ret;
10683 }
10684
10685 #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)10686 static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern,
10687 struct sock_reuseport *reuse,
10688 struct sock *sk, struct sk_buff *skb,
10689 struct sock *migrating_sk,
10690 u32 hash)
10691 {
10692 reuse_kern->skb = skb;
10693 reuse_kern->sk = sk;
10694 reuse_kern->selected_sk = NULL;
10695 reuse_kern->migrating_sk = migrating_sk;
10696 reuse_kern->data_end = skb->data + skb_headlen(skb);
10697 reuse_kern->hash = hash;
10698 reuse_kern->reuseport_id = reuse->reuseport_id;
10699 reuse_kern->bind_inany = reuse->bind_inany;
10700 }
10701
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)10702 struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
10703 struct bpf_prog *prog, struct sk_buff *skb,
10704 struct sock *migrating_sk,
10705 u32 hash)
10706 {
10707 struct sk_reuseport_kern reuse_kern;
10708 enum sk_action action;
10709
10710 bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, migrating_sk, hash);
10711 action = bpf_prog_run(prog, &reuse_kern);
10712
10713 if (action == SK_PASS)
10714 return reuse_kern.selected_sk;
10715 else
10716 return ERR_PTR(-ECONNREFUSED);
10717 }
10718
BPF_CALL_4(sk_select_reuseport,struct sk_reuseport_kern *,reuse_kern,struct bpf_map *,map,void *,key,u32,flags)10719 BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern,
10720 struct bpf_map *, map, void *, key, u32, flags)
10721 {
10722 bool is_sockarray = map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY;
10723 struct sock_reuseport *reuse;
10724 struct sock *selected_sk;
10725
10726 selected_sk = map->ops->map_lookup_elem(map, key);
10727 if (!selected_sk)
10728 return -ENOENT;
10729
10730 reuse = rcu_dereference(selected_sk->sk_reuseport_cb);
10731 if (!reuse) {
10732 /* Lookup in sock_map can return TCP ESTABLISHED sockets. */
10733 if (sk_is_refcounted(selected_sk))
10734 sock_put(selected_sk);
10735
10736 /* reuseport_array has only sk with non NULL sk_reuseport_cb.
10737 * The only (!reuse) case here is - the sk has already been
10738 * unhashed (e.g. by close()), so treat it as -ENOENT.
10739 *
10740 * Other maps (e.g. sock_map) do not provide this guarantee and
10741 * the sk may never be in the reuseport group to begin with.
10742 */
10743 return is_sockarray ? -ENOENT : -EINVAL;
10744 }
10745
10746 if (unlikely(reuse->reuseport_id != reuse_kern->reuseport_id)) {
10747 struct sock *sk = reuse_kern->sk;
10748
10749 if (sk->sk_protocol != selected_sk->sk_protocol)
10750 return -EPROTOTYPE;
10751 else if (sk->sk_family != selected_sk->sk_family)
10752 return -EAFNOSUPPORT;
10753
10754 /* Catch all. Likely bound to a different sockaddr. */
10755 return -EBADFD;
10756 }
10757
10758 reuse_kern->selected_sk = selected_sk;
10759
10760 return 0;
10761 }
10762
10763 static const struct bpf_func_proto sk_select_reuseport_proto = {
10764 .func = sk_select_reuseport,
10765 .gpl_only = false,
10766 .ret_type = RET_INTEGER,
10767 .arg1_type = ARG_PTR_TO_CTX,
10768 .arg2_type = ARG_CONST_MAP_PTR,
10769 .arg3_type = ARG_PTR_TO_MAP_KEY,
10770 .arg4_type = ARG_ANYTHING,
10771 };
10772
BPF_CALL_4(sk_reuseport_load_bytes,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len)10773 BPF_CALL_4(sk_reuseport_load_bytes,
10774 const struct sk_reuseport_kern *, reuse_kern, u32, offset,
10775 void *, to, u32, len)
10776 {
10777 return ____bpf_skb_load_bytes(reuse_kern->skb, offset, to, len);
10778 }
10779
10780 static const struct bpf_func_proto sk_reuseport_load_bytes_proto = {
10781 .func = sk_reuseport_load_bytes,
10782 .gpl_only = false,
10783 .ret_type = RET_INTEGER,
10784 .arg1_type = ARG_PTR_TO_CTX,
10785 .arg2_type = ARG_ANYTHING,
10786 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
10787 .arg4_type = ARG_CONST_SIZE,
10788 };
10789
BPF_CALL_5(sk_reuseport_load_bytes_relative,const struct sk_reuseport_kern *,reuse_kern,u32,offset,void *,to,u32,len,u32,start_header)10790 BPF_CALL_5(sk_reuseport_load_bytes_relative,
10791 const struct sk_reuseport_kern *, reuse_kern, u32, offset,
10792 void *, to, u32, len, u32, start_header)
10793 {
10794 return ____bpf_skb_load_bytes_relative(reuse_kern->skb, offset, to,
10795 len, start_header);
10796 }
10797
10798 static const struct bpf_func_proto sk_reuseport_load_bytes_relative_proto = {
10799 .func = sk_reuseport_load_bytes_relative,
10800 .gpl_only = false,
10801 .ret_type = RET_INTEGER,
10802 .arg1_type = ARG_PTR_TO_CTX,
10803 .arg2_type = ARG_ANYTHING,
10804 .arg3_type = ARG_PTR_TO_UNINIT_MEM,
10805 .arg4_type = ARG_CONST_SIZE,
10806 .arg5_type = ARG_ANYTHING,
10807 };
10808
10809 static const struct bpf_func_proto *
sk_reuseport_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)10810 sk_reuseport_func_proto(enum bpf_func_id func_id,
10811 const struct bpf_prog *prog)
10812 {
10813 switch (func_id) {
10814 case BPF_FUNC_sk_select_reuseport:
10815 return &sk_select_reuseport_proto;
10816 case BPF_FUNC_skb_load_bytes:
10817 return &sk_reuseport_load_bytes_proto;
10818 case BPF_FUNC_skb_load_bytes_relative:
10819 return &sk_reuseport_load_bytes_relative_proto;
10820 case BPF_FUNC_get_socket_cookie:
10821 return &bpf_get_socket_ptr_cookie_proto;
10822 case BPF_FUNC_ktime_get_coarse_ns:
10823 return &bpf_ktime_get_coarse_ns_proto;
10824 default:
10825 return bpf_base_func_proto(func_id);
10826 }
10827 }
10828
10829 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)10830 sk_reuseport_is_valid_access(int off, int size,
10831 enum bpf_access_type type,
10832 const struct bpf_prog *prog,
10833 struct bpf_insn_access_aux *info)
10834 {
10835 const u32 size_default = sizeof(__u32);
10836
10837 if (off < 0 || off >= sizeof(struct sk_reuseport_md) ||
10838 off % size || type != BPF_READ)
10839 return false;
10840
10841 switch (off) {
10842 case offsetof(struct sk_reuseport_md, data):
10843 info->reg_type = PTR_TO_PACKET;
10844 return size == sizeof(__u64);
10845
10846 case offsetof(struct sk_reuseport_md, data_end):
10847 info->reg_type = PTR_TO_PACKET_END;
10848 return size == sizeof(__u64);
10849
10850 case offsetof(struct sk_reuseport_md, hash):
10851 return size == size_default;
10852
10853 case offsetof(struct sk_reuseport_md, sk):
10854 info->reg_type = PTR_TO_SOCKET;
10855 return size == sizeof(__u64);
10856
10857 case offsetof(struct sk_reuseport_md, migrating_sk):
10858 info->reg_type = PTR_TO_SOCK_COMMON_OR_NULL;
10859 return size == sizeof(__u64);
10860
10861 /* Fields that allow narrowing */
10862 case bpf_ctx_range(struct sk_reuseport_md, eth_protocol):
10863 if (size < sizeof_field(struct sk_buff, protocol))
10864 return false;
10865 fallthrough;
10866 case bpf_ctx_range(struct sk_reuseport_md, ip_protocol):
10867 case bpf_ctx_range(struct sk_reuseport_md, bind_inany):
10868 case bpf_ctx_range(struct sk_reuseport_md, len):
10869 bpf_ctx_record_field_size(info, size_default);
10870 return bpf_ctx_narrow_access_ok(off, size, size_default);
10871
10872 default:
10873 return false;
10874 }
10875 }
10876
10877 #define SK_REUSEPORT_LOAD_FIELD(F) ({ \
10878 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_reuseport_kern, F), \
10879 si->dst_reg, si->src_reg, \
10880 bpf_target_off(struct sk_reuseport_kern, F, \
10881 sizeof_field(struct sk_reuseport_kern, F), \
10882 target_size)); \
10883 })
10884
10885 #define SK_REUSEPORT_LOAD_SKB_FIELD(SKB_FIELD) \
10886 SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern, \
10887 struct sk_buff, \
10888 skb, \
10889 SKB_FIELD)
10890
10891 #define SK_REUSEPORT_LOAD_SK_FIELD(SK_FIELD) \
10892 SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern, \
10893 struct sock, \
10894 sk, \
10895 SK_FIELD)
10896
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)10897 static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type,
10898 const struct bpf_insn *si,
10899 struct bpf_insn *insn_buf,
10900 struct bpf_prog *prog,
10901 u32 *target_size)
10902 {
10903 struct bpf_insn *insn = insn_buf;
10904
10905 switch (si->off) {
10906 case offsetof(struct sk_reuseport_md, data):
10907 SK_REUSEPORT_LOAD_SKB_FIELD(data);
10908 break;
10909
10910 case offsetof(struct sk_reuseport_md, len):
10911 SK_REUSEPORT_LOAD_SKB_FIELD(len);
10912 break;
10913
10914 case offsetof(struct sk_reuseport_md, eth_protocol):
10915 SK_REUSEPORT_LOAD_SKB_FIELD(protocol);
10916 break;
10917
10918 case offsetof(struct sk_reuseport_md, ip_protocol):
10919 SK_REUSEPORT_LOAD_SK_FIELD(sk_protocol);
10920 break;
10921
10922 case offsetof(struct sk_reuseport_md, data_end):
10923 SK_REUSEPORT_LOAD_FIELD(data_end);
10924 break;
10925
10926 case offsetof(struct sk_reuseport_md, hash):
10927 SK_REUSEPORT_LOAD_FIELD(hash);
10928 break;
10929
10930 case offsetof(struct sk_reuseport_md, bind_inany):
10931 SK_REUSEPORT_LOAD_FIELD(bind_inany);
10932 break;
10933
10934 case offsetof(struct sk_reuseport_md, sk):
10935 SK_REUSEPORT_LOAD_FIELD(sk);
10936 break;
10937
10938 case offsetof(struct sk_reuseport_md, migrating_sk):
10939 SK_REUSEPORT_LOAD_FIELD(migrating_sk);
10940 break;
10941 }
10942
10943 return insn - insn_buf;
10944 }
10945
10946 const struct bpf_verifier_ops sk_reuseport_verifier_ops = {
10947 .get_func_proto = sk_reuseport_func_proto,
10948 .is_valid_access = sk_reuseport_is_valid_access,
10949 .convert_ctx_access = sk_reuseport_convert_ctx_access,
10950 };
10951
10952 const struct bpf_prog_ops sk_reuseport_prog_ops = {
10953 };
10954
10955 DEFINE_STATIC_KEY_FALSE(bpf_sk_lookup_enabled);
10956 EXPORT_SYMBOL(bpf_sk_lookup_enabled);
10957
BPF_CALL_3(bpf_sk_lookup_assign,struct bpf_sk_lookup_kern *,ctx,struct sock *,sk,u64,flags)10958 BPF_CALL_3(bpf_sk_lookup_assign, struct bpf_sk_lookup_kern *, ctx,
10959 struct sock *, sk, u64, flags)
10960 {
10961 if (unlikely(flags & ~(BPF_SK_LOOKUP_F_REPLACE |
10962 BPF_SK_LOOKUP_F_NO_REUSEPORT)))
10963 return -EINVAL;
10964 if (unlikely(sk && sk_is_refcounted(sk)))
10965 return -ESOCKTNOSUPPORT; /* reject non-RCU freed sockets */
10966 if (unlikely(sk && sk_is_tcp(sk) && sk->sk_state != TCP_LISTEN))
10967 return -ESOCKTNOSUPPORT; /* only accept TCP socket in LISTEN */
10968 if (unlikely(sk && sk_is_udp(sk) && sk->sk_state != TCP_CLOSE))
10969 return -ESOCKTNOSUPPORT; /* only accept UDP socket in CLOSE */
10970
10971 /* Check if socket is suitable for packet L3/L4 protocol */
10972 if (sk && sk->sk_protocol != ctx->protocol)
10973 return -EPROTOTYPE;
10974 if (sk && sk->sk_family != ctx->family &&
10975 (sk->sk_family == AF_INET || ipv6_only_sock(sk)))
10976 return -EAFNOSUPPORT;
10977
10978 if (ctx->selected_sk && !(flags & BPF_SK_LOOKUP_F_REPLACE))
10979 return -EEXIST;
10980
10981 /* Select socket as lookup result */
10982 ctx->selected_sk = sk;
10983 ctx->no_reuseport = flags & BPF_SK_LOOKUP_F_NO_REUSEPORT;
10984 return 0;
10985 }
10986
10987 static const struct bpf_func_proto bpf_sk_lookup_assign_proto = {
10988 .func = bpf_sk_lookup_assign,
10989 .gpl_only = false,
10990 .ret_type = RET_INTEGER,
10991 .arg1_type = ARG_PTR_TO_CTX,
10992 .arg2_type = ARG_PTR_TO_SOCKET_OR_NULL,
10993 .arg3_type = ARG_ANYTHING,
10994 };
10995
10996 static const struct bpf_func_proto *
sk_lookup_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)10997 sk_lookup_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
10998 {
10999 switch (func_id) {
11000 case BPF_FUNC_perf_event_output:
11001 return &bpf_event_output_data_proto;
11002 case BPF_FUNC_sk_assign:
11003 return &bpf_sk_lookup_assign_proto;
11004 case BPF_FUNC_sk_release:
11005 return &bpf_sk_release_proto;
11006 default:
11007 return bpf_sk_base_func_proto(func_id);
11008 }
11009 }
11010
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)11011 static bool sk_lookup_is_valid_access(int off, int size,
11012 enum bpf_access_type type,
11013 const struct bpf_prog *prog,
11014 struct bpf_insn_access_aux *info)
11015 {
11016 if (off < 0 || off >= sizeof(struct bpf_sk_lookup))
11017 return false;
11018 if (off % size != 0)
11019 return false;
11020 if (type != BPF_READ)
11021 return false;
11022
11023 switch (off) {
11024 case offsetof(struct bpf_sk_lookup, sk):
11025 info->reg_type = PTR_TO_SOCKET_OR_NULL;
11026 return size == sizeof(__u64);
11027
11028 case bpf_ctx_range(struct bpf_sk_lookup, family):
11029 case bpf_ctx_range(struct bpf_sk_lookup, protocol):
11030 case bpf_ctx_range(struct bpf_sk_lookup, remote_ip4):
11031 case bpf_ctx_range(struct bpf_sk_lookup, local_ip4):
11032 case bpf_ctx_range_till(struct bpf_sk_lookup, remote_ip6[0], remote_ip6[3]):
11033 case bpf_ctx_range_till(struct bpf_sk_lookup, local_ip6[0], local_ip6[3]):
11034 case bpf_ctx_range(struct bpf_sk_lookup, local_port):
11035 case bpf_ctx_range(struct bpf_sk_lookup, ingress_ifindex):
11036 bpf_ctx_record_field_size(info, sizeof(__u32));
11037 return bpf_ctx_narrow_access_ok(off, size, sizeof(__u32));
11038
11039 case bpf_ctx_range(struct bpf_sk_lookup, remote_port):
11040 /* Allow 4-byte access to 2-byte field for backward compatibility */
11041 if (size == sizeof(__u32))
11042 return true;
11043 bpf_ctx_record_field_size(info, sizeof(__be16));
11044 return bpf_ctx_narrow_access_ok(off, size, sizeof(__be16));
11045
11046 case offsetofend(struct bpf_sk_lookup, remote_port) ...
11047 offsetof(struct bpf_sk_lookup, local_ip4) - 1:
11048 /* Allow access to zero padding for backward compatibility */
11049 bpf_ctx_record_field_size(info, sizeof(__u16));
11050 return bpf_ctx_narrow_access_ok(off, size, sizeof(__u16));
11051
11052 default:
11053 return false;
11054 }
11055 }
11056
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)11057 static u32 sk_lookup_convert_ctx_access(enum bpf_access_type type,
11058 const struct bpf_insn *si,
11059 struct bpf_insn *insn_buf,
11060 struct bpf_prog *prog,
11061 u32 *target_size)
11062 {
11063 struct bpf_insn *insn = insn_buf;
11064
11065 switch (si->off) {
11066 case offsetof(struct bpf_sk_lookup, sk):
11067 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11068 offsetof(struct bpf_sk_lookup_kern, selected_sk));
11069 break;
11070
11071 case offsetof(struct bpf_sk_lookup, family):
11072 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11073 bpf_target_off(struct bpf_sk_lookup_kern,
11074 family, 2, target_size));
11075 break;
11076
11077 case offsetof(struct bpf_sk_lookup, protocol):
11078 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11079 bpf_target_off(struct bpf_sk_lookup_kern,
11080 protocol, 2, target_size));
11081 break;
11082
11083 case offsetof(struct bpf_sk_lookup, remote_ip4):
11084 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11085 bpf_target_off(struct bpf_sk_lookup_kern,
11086 v4.saddr, 4, target_size));
11087 break;
11088
11089 case offsetof(struct bpf_sk_lookup, local_ip4):
11090 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11091 bpf_target_off(struct bpf_sk_lookup_kern,
11092 v4.daddr, 4, target_size));
11093 break;
11094
11095 case bpf_ctx_range_till(struct bpf_sk_lookup,
11096 remote_ip6[0], remote_ip6[3]): {
11097 #if IS_ENABLED(CONFIG_IPV6)
11098 int off = si->off;
11099
11100 off -= offsetof(struct bpf_sk_lookup, remote_ip6[0]);
11101 off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
11102 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11103 offsetof(struct bpf_sk_lookup_kern, v6.saddr));
11104 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
11105 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
11106 #else
11107 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11108 #endif
11109 break;
11110 }
11111 case bpf_ctx_range_till(struct bpf_sk_lookup,
11112 local_ip6[0], local_ip6[3]): {
11113 #if IS_ENABLED(CONFIG_IPV6)
11114 int off = si->off;
11115
11116 off -= offsetof(struct bpf_sk_lookup, local_ip6[0]);
11117 off += bpf_target_off(struct in6_addr, s6_addr32[0], 4, target_size);
11118 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg, si->src_reg,
11119 offsetof(struct bpf_sk_lookup_kern, v6.daddr));
11120 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
11121 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg, off);
11122 #else
11123 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11124 #endif
11125 break;
11126 }
11127 case offsetof(struct bpf_sk_lookup, remote_port):
11128 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11129 bpf_target_off(struct bpf_sk_lookup_kern,
11130 sport, 2, target_size));
11131 break;
11132
11133 case offsetofend(struct bpf_sk_lookup, remote_port):
11134 *target_size = 2;
11135 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
11136 break;
11137
11138 case offsetof(struct bpf_sk_lookup, local_port):
11139 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
11140 bpf_target_off(struct bpf_sk_lookup_kern,
11141 dport, 2, target_size));
11142 break;
11143
11144 case offsetof(struct bpf_sk_lookup, ingress_ifindex):
11145 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
11146 bpf_target_off(struct bpf_sk_lookup_kern,
11147 ingress_ifindex, 4, target_size));
11148 break;
11149 }
11150
11151 return insn - insn_buf;
11152 }
11153
11154 const struct bpf_prog_ops sk_lookup_prog_ops = {
11155 .test_run = bpf_prog_test_run_sk_lookup,
11156 };
11157
11158 const struct bpf_verifier_ops sk_lookup_verifier_ops = {
11159 .get_func_proto = sk_lookup_func_proto,
11160 .is_valid_access = sk_lookup_is_valid_access,
11161 .convert_ctx_access = sk_lookup_convert_ctx_access,
11162 };
11163
11164 #endif /* CONFIG_INET */
11165
DEFINE_BPF_DISPATCHER(xdp)11166 DEFINE_BPF_DISPATCHER(xdp)
11167
11168 void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog)
11169 {
11170 bpf_dispatcher_change_prog(BPF_DISPATCHER_PTR(xdp), prev_prog, prog);
11171 }
11172
BTF_ID_LIST_GLOBAL(btf_sock_ids,MAX_BTF_SOCK_TYPE)11173 BTF_ID_LIST_GLOBAL(btf_sock_ids, MAX_BTF_SOCK_TYPE)
11174 #define BTF_SOCK_TYPE(name, type) BTF_ID(struct, type)
11175 BTF_SOCK_TYPE_xxx
11176 #undef BTF_SOCK_TYPE
11177
11178 BPF_CALL_1(bpf_skc_to_tcp6_sock, struct sock *, sk)
11179 {
11180 /* tcp6_sock type is not generated in dwarf and hence btf,
11181 * trigger an explicit type generation here.
11182 */
11183 BTF_TYPE_EMIT(struct tcp6_sock);
11184 if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP &&
11185 sk->sk_family == AF_INET6)
11186 return (unsigned long)sk;
11187
11188 return (unsigned long)NULL;
11189 }
11190
11191 const struct bpf_func_proto bpf_skc_to_tcp6_sock_proto = {
11192 .func = bpf_skc_to_tcp6_sock,
11193 .gpl_only = false,
11194 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
11195 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11196 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_TCP6],
11197 };
11198
BPF_CALL_1(bpf_skc_to_tcp_sock,struct sock *,sk)11199 BPF_CALL_1(bpf_skc_to_tcp_sock, struct sock *, sk)
11200 {
11201 if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_TCP)
11202 return (unsigned long)sk;
11203
11204 return (unsigned long)NULL;
11205 }
11206
11207 const struct bpf_func_proto bpf_skc_to_tcp_sock_proto = {
11208 .func = bpf_skc_to_tcp_sock,
11209 .gpl_only = false,
11210 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
11211 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11212 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_TCP],
11213 };
11214
BPF_CALL_1(bpf_skc_to_tcp_timewait_sock,struct sock *,sk)11215 BPF_CALL_1(bpf_skc_to_tcp_timewait_sock, struct sock *, sk)
11216 {
11217 /* BTF types for tcp_timewait_sock and inet_timewait_sock are not
11218 * generated if CONFIG_INET=n. Trigger an explicit generation here.
11219 */
11220 BTF_TYPE_EMIT(struct inet_timewait_sock);
11221 BTF_TYPE_EMIT(struct tcp_timewait_sock);
11222
11223 #ifdef CONFIG_INET
11224 if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_TIME_WAIT)
11225 return (unsigned long)sk;
11226 #endif
11227
11228 #if IS_BUILTIN(CONFIG_IPV6)
11229 if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_TIME_WAIT)
11230 return (unsigned long)sk;
11231 #endif
11232
11233 return (unsigned long)NULL;
11234 }
11235
11236 const struct bpf_func_proto bpf_skc_to_tcp_timewait_sock_proto = {
11237 .func = bpf_skc_to_tcp_timewait_sock,
11238 .gpl_only = false,
11239 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
11240 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11241 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_TCP_TW],
11242 };
11243
BPF_CALL_1(bpf_skc_to_tcp_request_sock,struct sock *,sk)11244 BPF_CALL_1(bpf_skc_to_tcp_request_sock, struct sock *, sk)
11245 {
11246 #ifdef CONFIG_INET
11247 if (sk && sk->sk_prot == &tcp_prot && sk->sk_state == TCP_NEW_SYN_RECV)
11248 return (unsigned long)sk;
11249 #endif
11250
11251 #if IS_BUILTIN(CONFIG_IPV6)
11252 if (sk && sk->sk_prot == &tcpv6_prot && sk->sk_state == TCP_NEW_SYN_RECV)
11253 return (unsigned long)sk;
11254 #endif
11255
11256 return (unsigned long)NULL;
11257 }
11258
11259 const struct bpf_func_proto bpf_skc_to_tcp_request_sock_proto = {
11260 .func = bpf_skc_to_tcp_request_sock,
11261 .gpl_only = false,
11262 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
11263 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11264 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_TCP_REQ],
11265 };
11266
BPF_CALL_1(bpf_skc_to_udp6_sock,struct sock *,sk)11267 BPF_CALL_1(bpf_skc_to_udp6_sock, struct sock *, sk)
11268 {
11269 /* udp6_sock type is not generated in dwarf and hence btf,
11270 * trigger an explicit type generation here.
11271 */
11272 BTF_TYPE_EMIT(struct udp6_sock);
11273 if (sk && sk_fullsock(sk) && sk->sk_protocol == IPPROTO_UDP &&
11274 sk->sk_type == SOCK_DGRAM && sk->sk_family == AF_INET6)
11275 return (unsigned long)sk;
11276
11277 return (unsigned long)NULL;
11278 }
11279
11280 const struct bpf_func_proto bpf_skc_to_udp6_sock_proto = {
11281 .func = bpf_skc_to_udp6_sock,
11282 .gpl_only = false,
11283 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
11284 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11285 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_UDP6],
11286 };
11287
BPF_CALL_1(bpf_skc_to_unix_sock,struct sock *,sk)11288 BPF_CALL_1(bpf_skc_to_unix_sock, struct sock *, sk)
11289 {
11290 /* unix_sock type is not generated in dwarf and hence btf,
11291 * trigger an explicit type generation here.
11292 */
11293 BTF_TYPE_EMIT(struct unix_sock);
11294 if (sk && sk_fullsock(sk) && sk->sk_family == AF_UNIX)
11295 return (unsigned long)sk;
11296
11297 return (unsigned long)NULL;
11298 }
11299
11300 const struct bpf_func_proto bpf_skc_to_unix_sock_proto = {
11301 .func = bpf_skc_to_unix_sock,
11302 .gpl_only = false,
11303 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
11304 .arg1_type = ARG_PTR_TO_BTF_ID_SOCK_COMMON,
11305 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_UNIX],
11306 };
11307
BPF_CALL_1(bpf_skc_to_mptcp_sock,struct sock *,sk)11308 BPF_CALL_1(bpf_skc_to_mptcp_sock, struct sock *, sk)
11309 {
11310 BTF_TYPE_EMIT(struct mptcp_sock);
11311 return (unsigned long)bpf_mptcp_sock_from_subflow(sk);
11312 }
11313
11314 const struct bpf_func_proto bpf_skc_to_mptcp_sock_proto = {
11315 .func = bpf_skc_to_mptcp_sock,
11316 .gpl_only = false,
11317 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
11318 .arg1_type = ARG_PTR_TO_SOCK_COMMON,
11319 .ret_btf_id = &btf_sock_ids[BTF_SOCK_TYPE_MPTCP],
11320 };
11321
BPF_CALL_1(bpf_sock_from_file,struct file *,file)11322 BPF_CALL_1(bpf_sock_from_file, struct file *, file)
11323 {
11324 return (unsigned long)sock_from_file(file);
11325 }
11326
11327 BTF_ID_LIST(bpf_sock_from_file_btf_ids)
11328 BTF_ID(struct, socket)
11329 BTF_ID(struct, file)
11330
11331 const struct bpf_func_proto bpf_sock_from_file_proto = {
11332 .func = bpf_sock_from_file,
11333 .gpl_only = false,
11334 .ret_type = RET_PTR_TO_BTF_ID_OR_NULL,
11335 .ret_btf_id = &bpf_sock_from_file_btf_ids[0],
11336 .arg1_type = ARG_PTR_TO_BTF_ID,
11337 .arg1_btf_id = &bpf_sock_from_file_btf_ids[1],
11338 };
11339
11340 static const struct bpf_func_proto *
bpf_sk_base_func_proto(enum bpf_func_id func_id)11341 bpf_sk_base_func_proto(enum bpf_func_id func_id)
11342 {
11343 const struct bpf_func_proto *func;
11344
11345 switch (func_id) {
11346 case BPF_FUNC_skc_to_tcp6_sock:
11347 func = &bpf_skc_to_tcp6_sock_proto;
11348 break;
11349 case BPF_FUNC_skc_to_tcp_sock:
11350 func = &bpf_skc_to_tcp_sock_proto;
11351 break;
11352 case BPF_FUNC_skc_to_tcp_timewait_sock:
11353 func = &bpf_skc_to_tcp_timewait_sock_proto;
11354 break;
11355 case BPF_FUNC_skc_to_tcp_request_sock:
11356 func = &bpf_skc_to_tcp_request_sock_proto;
11357 break;
11358 case BPF_FUNC_skc_to_udp6_sock:
11359 func = &bpf_skc_to_udp6_sock_proto;
11360 break;
11361 case BPF_FUNC_skc_to_unix_sock:
11362 func = &bpf_skc_to_unix_sock_proto;
11363 break;
11364 case BPF_FUNC_skc_to_mptcp_sock:
11365 func = &bpf_skc_to_mptcp_sock_proto;
11366 break;
11367 case BPF_FUNC_ktime_get_coarse_ns:
11368 return &bpf_ktime_get_coarse_ns_proto;
11369 default:
11370 return bpf_base_func_proto(func_id);
11371 }
11372
11373 if (!perfmon_capable())
11374 return NULL;
11375
11376 return func;
11377 }
11378