1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * xfrm_input.c
4 *
5 * Changes:
6 * YOSHIFUJI Hideaki @USAGI
7 * Split up af-specific portion
8 *
9 */
10
11 #include <linux/bottom_half.h>
12 #include <linux/cache.h>
13 #include <linux/interrupt.h>
14 #include <linux/slab.h>
15 #include <linux/module.h>
16 #include <linux/netdevice.h>
17 #include <linux/percpu.h>
18 #include <net/dst.h>
19 #include <net/ip.h>
20 #include <net/xfrm.h>
21 #include <net/ip_tunnels.h>
22 #include <net/ip6_tunnel.h>
23 #include <net/dst_metadata.h>
24
25 #include "xfrm_inout.h"
26
27 struct xfrm_trans_tasklet {
28 struct work_struct work;
29 spinlock_t queue_lock;
30 struct sk_buff_head queue;
31 };
32
33 struct xfrm_trans_cb {
34 union {
35 struct inet_skb_parm h4;
36 #if IS_ENABLED(CONFIG_IPV6)
37 struct inet6_skb_parm h6;
38 #endif
39 } header;
40 int (*finish)(struct net *net, struct sock *sk, struct sk_buff *skb);
41 struct net *net;
42 };
43
44 #define XFRM_TRANS_SKB_CB(__skb) ((struct xfrm_trans_cb *)&((__skb)->cb[0]))
45
46 static DEFINE_SPINLOCK(xfrm_input_afinfo_lock);
47 static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[2][AF_INET6 + 1];
48
49 static struct gro_cells gro_cells;
50 static struct net_device xfrm_napi_dev;
51
52 static DEFINE_PER_CPU(struct xfrm_trans_tasklet, xfrm_trans_tasklet);
53
xfrm_input_register_afinfo(const struct xfrm_input_afinfo * afinfo)54 int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo)
55 {
56 int err = 0;
57
58 if (WARN_ON(afinfo->family > AF_INET6))
59 return -EAFNOSUPPORT;
60
61 spin_lock_bh(&xfrm_input_afinfo_lock);
62 if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family]))
63 err = -EEXIST;
64 else
65 rcu_assign_pointer(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], afinfo);
66 spin_unlock_bh(&xfrm_input_afinfo_lock);
67 return err;
68 }
69 EXPORT_SYMBOL(xfrm_input_register_afinfo);
70
xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo * afinfo)71 int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo)
72 {
73 int err = 0;
74
75 spin_lock_bh(&xfrm_input_afinfo_lock);
76 if (likely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family])) {
77 if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family] != afinfo))
78 err = -EINVAL;
79 else
80 RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], NULL);
81 }
82 spin_unlock_bh(&xfrm_input_afinfo_lock);
83 synchronize_rcu();
84 return err;
85 }
86 EXPORT_SYMBOL(xfrm_input_unregister_afinfo);
87
xfrm_input_get_afinfo(u8 family,bool is_ipip)88 static const struct xfrm_input_afinfo *xfrm_input_get_afinfo(u8 family, bool is_ipip)
89 {
90 const struct xfrm_input_afinfo *afinfo;
91
92 if (WARN_ON_ONCE(family > AF_INET6))
93 return NULL;
94
95 rcu_read_lock();
96 afinfo = rcu_dereference(xfrm_input_afinfo[is_ipip][family]);
97 if (unlikely(!afinfo))
98 rcu_read_unlock();
99 return afinfo;
100 }
101
xfrm_rcv_cb(struct sk_buff * skb,unsigned int family,u8 protocol,int err)102 static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
103 int err)
104 {
105 bool is_ipip = (protocol == IPPROTO_IPIP || protocol == IPPROTO_IPV6);
106 const struct xfrm_input_afinfo *afinfo;
107 int ret;
108
109 afinfo = xfrm_input_get_afinfo(family, is_ipip);
110 if (!afinfo)
111 return -EAFNOSUPPORT;
112
113 ret = afinfo->callback(skb, protocol, err);
114 rcu_read_unlock();
115
116 return ret;
117 }
118
secpath_set(struct sk_buff * skb)119 struct sec_path *secpath_set(struct sk_buff *skb)
120 {
121 struct sec_path *sp, *tmp = skb_ext_find(skb, SKB_EXT_SEC_PATH);
122
123 sp = skb_ext_add(skb, SKB_EXT_SEC_PATH);
124 if (!sp)
125 return NULL;
126
127 if (tmp) /* reused existing one (was COW'd if needed) */
128 return sp;
129
130 /* allocated new secpath */
131 memset(sp->ovec, 0, sizeof(sp->ovec));
132 sp->olen = 0;
133 sp->len = 0;
134
135 return sp;
136 }
137 EXPORT_SYMBOL(secpath_set);
138
139 /* Fetch spi and seq from ipsec header */
140
xfrm_parse_spi(struct sk_buff * skb,u8 nexthdr,__be32 * spi,__be32 * seq)141 int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
142 {
143 int offset, offset_seq;
144 int hlen;
145
146 switch (nexthdr) {
147 case IPPROTO_AH:
148 hlen = sizeof(struct ip_auth_hdr);
149 offset = offsetof(struct ip_auth_hdr, spi);
150 offset_seq = offsetof(struct ip_auth_hdr, seq_no);
151 break;
152 case IPPROTO_ESP:
153 hlen = sizeof(struct ip_esp_hdr);
154 offset = offsetof(struct ip_esp_hdr, spi);
155 offset_seq = offsetof(struct ip_esp_hdr, seq_no);
156 break;
157 case IPPROTO_COMP:
158 if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
159 return -EINVAL;
160 *spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2)));
161 *seq = 0;
162 return 0;
163 default:
164 return 1;
165 }
166
167 if (!pskb_may_pull(skb, hlen))
168 return -EINVAL;
169
170 *spi = *(__be32 *)(skb_transport_header(skb) + offset);
171 *seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
172 return 0;
173 }
174 EXPORT_SYMBOL(xfrm_parse_spi);
175
xfrm4_remove_beet_encap(struct xfrm_state * x,struct sk_buff * skb)176 static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
177 {
178 struct iphdr *iph;
179 int optlen = 0;
180 int err = -EINVAL;
181
182 if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
183 struct ip_beet_phdr *ph;
184 int phlen;
185
186 if (!pskb_may_pull(skb, sizeof(*ph)))
187 goto out;
188
189 ph = (struct ip_beet_phdr *)skb->data;
190
191 phlen = sizeof(*ph) + ph->padlen;
192 optlen = ph->hdrlen * 8 + (IPV4_BEET_PHMAXLEN - phlen);
193 if (optlen < 0 || optlen & 3 || optlen > 250)
194 goto out;
195
196 XFRM_MODE_SKB_CB(skb)->protocol = ph->nexthdr;
197
198 if (!pskb_may_pull(skb, phlen))
199 goto out;
200 __skb_pull(skb, phlen);
201 }
202
203 skb_push(skb, sizeof(*iph));
204 skb_reset_network_header(skb);
205 skb_mac_header_rebuild(skb);
206
207 xfrm4_beet_make_header(skb);
208
209 iph = ip_hdr(skb);
210
211 iph->ihl += optlen / 4;
212 iph->tot_len = htons(skb->len);
213 iph->daddr = x->sel.daddr.a4;
214 iph->saddr = x->sel.saddr.a4;
215 iph->check = 0;
216 iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
217 err = 0;
218 out:
219 return err;
220 }
221
ipip_ecn_decapsulate(struct sk_buff * skb)222 static void ipip_ecn_decapsulate(struct sk_buff *skb)
223 {
224 struct iphdr *inner_iph = ipip_hdr(skb);
225
226 if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
227 IP_ECN_set_ce(inner_iph);
228 }
229
xfrm4_remove_tunnel_encap(struct xfrm_state * x,struct sk_buff * skb)230 static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
231 {
232 int err = -EINVAL;
233
234 if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
235 goto out;
236
237 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
238 goto out;
239
240 err = skb_unclone(skb, GFP_ATOMIC);
241 if (err)
242 goto out;
243
244 if (x->props.flags & XFRM_STATE_DECAP_DSCP)
245 ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
246 if (!(x->props.flags & XFRM_STATE_NOECN))
247 ipip_ecn_decapsulate(skb);
248
249 skb_reset_network_header(skb);
250 skb_mac_header_rebuild(skb);
251 if (skb->mac_len)
252 eth_hdr(skb)->h_proto = skb->protocol;
253
254 err = 0;
255
256 out:
257 return err;
258 }
259
ipip6_ecn_decapsulate(struct sk_buff * skb)260 static void ipip6_ecn_decapsulate(struct sk_buff *skb)
261 {
262 struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
263
264 if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
265 IP6_ECN_set_ce(skb, inner_iph);
266 }
267
xfrm6_remove_tunnel_encap(struct xfrm_state * x,struct sk_buff * skb)268 static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
269 {
270 int err = -EINVAL;
271
272 if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
273 goto out;
274 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
275 goto out;
276
277 err = skb_unclone(skb, GFP_ATOMIC);
278 if (err)
279 goto out;
280
281 if (x->props.flags & XFRM_STATE_DECAP_DSCP)
282 ipv6_copy_dscp(ipv6_get_dsfield(ipv6_hdr(skb)),
283 ipipv6_hdr(skb));
284 if (!(x->props.flags & XFRM_STATE_NOECN))
285 ipip6_ecn_decapsulate(skb);
286
287 skb_reset_network_header(skb);
288 skb_mac_header_rebuild(skb);
289 if (skb->mac_len)
290 eth_hdr(skb)->h_proto = skb->protocol;
291
292 err = 0;
293
294 out:
295 return err;
296 }
297
xfrm6_remove_beet_encap(struct xfrm_state * x,struct sk_buff * skb)298 static int xfrm6_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
299 {
300 struct ipv6hdr *ip6h;
301 int size = sizeof(struct ipv6hdr);
302 int err;
303
304 err = skb_cow_head(skb, size + skb->mac_len);
305 if (err)
306 goto out;
307
308 __skb_push(skb, size);
309 skb_reset_network_header(skb);
310 skb_mac_header_rebuild(skb);
311
312 xfrm6_beet_make_header(skb);
313
314 ip6h = ipv6_hdr(skb);
315 ip6h->payload_len = htons(skb->len - size);
316 ip6h->daddr = x->sel.daddr.in6;
317 ip6h->saddr = x->sel.saddr.in6;
318 err = 0;
319 out:
320 return err;
321 }
322
323 /* Remove encapsulation header.
324 *
325 * The IP header will be moved over the top of the encapsulation
326 * header.
327 *
328 * On entry, the transport header shall point to where the IP header
329 * should be and the network header shall be set to where the IP
330 * header currently is. skb->data shall point to the start of the
331 * payload.
332 */
333 static int
xfrm_inner_mode_encap_remove(struct xfrm_state * x,const struct xfrm_mode * inner_mode,struct sk_buff * skb)334 xfrm_inner_mode_encap_remove(struct xfrm_state *x,
335 const struct xfrm_mode *inner_mode,
336 struct sk_buff *skb)
337 {
338 switch (inner_mode->encap) {
339 case XFRM_MODE_BEET:
340 if (inner_mode->family == AF_INET)
341 return xfrm4_remove_beet_encap(x, skb);
342 if (inner_mode->family == AF_INET6)
343 return xfrm6_remove_beet_encap(x, skb);
344 break;
345 case XFRM_MODE_TUNNEL:
346 if (inner_mode->family == AF_INET)
347 return xfrm4_remove_tunnel_encap(x, skb);
348 if (inner_mode->family == AF_INET6)
349 return xfrm6_remove_tunnel_encap(x, skb);
350 break;
351 }
352
353 WARN_ON_ONCE(1);
354 return -EOPNOTSUPP;
355 }
356
xfrm_prepare_input(struct xfrm_state * x,struct sk_buff * skb)357 static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
358 {
359 const struct xfrm_mode *inner_mode = &x->inner_mode;
360
361 switch (x->outer_mode.family) {
362 case AF_INET:
363 xfrm4_extract_header(skb);
364 break;
365 case AF_INET6:
366 xfrm6_extract_header(skb);
367 break;
368 default:
369 WARN_ON_ONCE(1);
370 return -EAFNOSUPPORT;
371 }
372
373 if (x->sel.family == AF_UNSPEC) {
374 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
375 if (!inner_mode)
376 return -EAFNOSUPPORT;
377 }
378
379 switch (inner_mode->family) {
380 case AF_INET:
381 skb->protocol = htons(ETH_P_IP);
382 break;
383 case AF_INET6:
384 skb->protocol = htons(ETH_P_IPV6);
385 break;
386 default:
387 WARN_ON_ONCE(1);
388 break;
389 }
390
391 return xfrm_inner_mode_encap_remove(x, inner_mode, skb);
392 }
393
394 /* Remove encapsulation header.
395 *
396 * The IP header will be moved over the top of the encapsulation header.
397 *
398 * On entry, skb_transport_header() shall point to where the IP header
399 * should be and skb_network_header() shall be set to where the IP header
400 * currently is. skb->data shall point to the start of the payload.
401 */
xfrm4_transport_input(struct xfrm_state * x,struct sk_buff * skb)402 static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
403 {
404 int ihl = skb->data - skb_transport_header(skb);
405
406 if (skb->transport_header != skb->network_header) {
407 memmove(skb_transport_header(skb),
408 skb_network_header(skb), ihl);
409 skb->network_header = skb->transport_header;
410 }
411 ip_hdr(skb)->tot_len = htons(skb->len + ihl);
412 skb_reset_transport_header(skb);
413 return 0;
414 }
415
xfrm6_transport_input(struct xfrm_state * x,struct sk_buff * skb)416 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
417 {
418 #if IS_ENABLED(CONFIG_IPV6)
419 int ihl = skb->data - skb_transport_header(skb);
420
421 if (skb->transport_header != skb->network_header) {
422 memmove(skb_transport_header(skb),
423 skb_network_header(skb), ihl);
424 skb->network_header = skb->transport_header;
425 }
426 ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
427 sizeof(struct ipv6hdr));
428 skb_reset_transport_header(skb);
429 return 0;
430 #else
431 WARN_ON_ONCE(1);
432 return -EAFNOSUPPORT;
433 #endif
434 }
435
xfrm_inner_mode_input(struct xfrm_state * x,const struct xfrm_mode * inner_mode,struct sk_buff * skb)436 static int xfrm_inner_mode_input(struct xfrm_state *x,
437 const struct xfrm_mode *inner_mode,
438 struct sk_buff *skb)
439 {
440 switch (inner_mode->encap) {
441 case XFRM_MODE_BEET:
442 case XFRM_MODE_TUNNEL:
443 return xfrm_prepare_input(x, skb);
444 case XFRM_MODE_TRANSPORT:
445 if (inner_mode->family == AF_INET)
446 return xfrm4_transport_input(x, skb);
447 if (inner_mode->family == AF_INET6)
448 return xfrm6_transport_input(x, skb);
449 break;
450 case XFRM_MODE_ROUTEOPTIMIZATION:
451 WARN_ON_ONCE(1);
452 break;
453 default:
454 WARN_ON_ONCE(1);
455 break;
456 }
457
458 return -EOPNOTSUPP;
459 }
460
xfrm_input(struct sk_buff * skb,int nexthdr,__be32 spi,int encap_type)461 int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
462 {
463 const struct xfrm_state_afinfo *afinfo;
464 struct net *net = dev_net(skb->dev);
465 const struct xfrm_mode *inner_mode;
466 int err;
467 __be32 seq;
468 __be32 seq_hi;
469 struct xfrm_state *x = NULL;
470 xfrm_address_t *daddr;
471 u32 mark = skb->mark;
472 unsigned int family = AF_UNSPEC;
473 int decaps = 0;
474 int async = 0;
475 bool xfrm_gro = false;
476 bool crypto_done = false;
477 struct xfrm_offload *xo = xfrm_offload(skb);
478 struct sec_path *sp;
479
480 if (encap_type < 0) {
481 x = xfrm_input_state(skb);
482
483 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
484 if (x->km.state == XFRM_STATE_ACQ)
485 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
486 else
487 XFRM_INC_STATS(net,
488 LINUX_MIB_XFRMINSTATEINVALID);
489
490 if (encap_type == -1)
491 dev_put(skb->dev);
492 goto drop;
493 }
494
495 family = x->outer_mode.family;
496
497 /* An encap_type of -1 indicates async resumption. */
498 if (encap_type == -1) {
499 async = 1;
500 seq = XFRM_SKB_CB(skb)->seq.input.low;
501 goto resume;
502 }
503
504 /* encap_type < -1 indicates a GRO call. */
505 encap_type = 0;
506 seq = XFRM_SPI_SKB_CB(skb)->seq;
507
508 if (xo && (xo->flags & CRYPTO_DONE)) {
509 crypto_done = true;
510 family = XFRM_SPI_SKB_CB(skb)->family;
511
512 if (!(xo->status & CRYPTO_SUCCESS)) {
513 if (xo->status &
514 (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
515 CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
516 CRYPTO_TUNNEL_AH_AUTH_FAILED |
517 CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
518
519 xfrm_audit_state_icvfail(x, skb,
520 x->type->proto);
521 x->stats.integrity_failed++;
522 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
523 goto drop;
524 }
525
526 if (xo->status & CRYPTO_INVALID_PROTOCOL) {
527 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
528 goto drop;
529 }
530
531 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
532 goto drop;
533 }
534
535 if (xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
536 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
537 goto drop;
538 }
539 }
540
541 goto lock;
542 }
543
544 family = XFRM_SPI_SKB_CB(skb)->family;
545
546 /* if tunnel is present override skb->mark value with tunnel i_key */
547 switch (family) {
548 case AF_INET:
549 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
550 mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
551 break;
552 case AF_INET6:
553 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
554 mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
555 break;
556 }
557
558 sp = secpath_set(skb);
559 if (!sp) {
560 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
561 goto drop;
562 }
563
564 seq = 0;
565 if (!spi && xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
566 secpath_reset(skb);
567 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
568 goto drop;
569 }
570
571 daddr = (xfrm_address_t *)(skb_network_header(skb) +
572 XFRM_SPI_SKB_CB(skb)->daddroff);
573 do {
574 sp = skb_sec_path(skb);
575
576 if (sp->len == XFRM_MAX_DEPTH) {
577 secpath_reset(skb);
578 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
579 goto drop;
580 }
581
582 x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
583 if (x == NULL) {
584 secpath_reset(skb);
585 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
586 xfrm_audit_state_notfound(skb, family, spi, seq);
587 goto drop;
588 }
589
590 skb->mark = xfrm_smark_get(skb->mark, x);
591
592 sp->xvec[sp->len++] = x;
593
594 skb_dst_force(skb);
595 if (!skb_dst(skb)) {
596 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
597 goto drop;
598 }
599
600 lock:
601 spin_lock(&x->lock);
602
603 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
604 if (x->km.state == XFRM_STATE_ACQ)
605 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
606 else
607 XFRM_INC_STATS(net,
608 LINUX_MIB_XFRMINSTATEINVALID);
609 goto drop_unlock;
610 }
611
612 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
613 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
614 goto drop_unlock;
615 }
616
617 if (xfrm_replay_check(x, skb, seq)) {
618 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
619 goto drop_unlock;
620 }
621
622 if (xfrm_state_check_expire(x)) {
623 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
624 goto drop_unlock;
625 }
626
627 spin_unlock(&x->lock);
628
629 if (xfrm_tunnel_check(skb, x, family)) {
630 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
631 goto drop;
632 }
633
634 seq_hi = htonl(xfrm_replay_seqhi(x, seq));
635
636 XFRM_SKB_CB(skb)->seq.input.low = seq;
637 XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
638
639 dev_hold(skb->dev);
640
641 if (crypto_done)
642 nexthdr = x->type_offload->input_tail(x, skb);
643 else
644 nexthdr = x->type->input(x, skb);
645
646 if (nexthdr == -EINPROGRESS)
647 return 0;
648 resume:
649 dev_put(skb->dev);
650
651 spin_lock(&x->lock);
652 if (nexthdr < 0) {
653 if (nexthdr == -EBADMSG) {
654 xfrm_audit_state_icvfail(x, skb,
655 x->type->proto);
656 x->stats.integrity_failed++;
657 }
658 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
659 goto drop_unlock;
660 }
661
662 /* only the first xfrm gets the encap type */
663 encap_type = 0;
664
665 if (xfrm_replay_recheck(x, skb, seq)) {
666 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
667 goto drop_unlock;
668 }
669
670 xfrm_replay_advance(x, seq);
671
672 x->curlft.bytes += skb->len;
673 x->curlft.packets++;
674
675 spin_unlock(&x->lock);
676
677 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
678
679 inner_mode = &x->inner_mode;
680
681 if (x->sel.family == AF_UNSPEC) {
682 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
683 if (inner_mode == NULL) {
684 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
685 goto drop;
686 }
687 }
688
689 if (xfrm_inner_mode_input(x, inner_mode, skb)) {
690 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
691 goto drop;
692 }
693
694 if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
695 decaps = 1;
696 break;
697 }
698
699 /*
700 * We need the inner address. However, we only get here for
701 * transport mode so the outer address is identical.
702 */
703 daddr = &x->id.daddr;
704 family = x->outer_mode.family;
705
706 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
707 if (err < 0) {
708 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
709 goto drop;
710 }
711 crypto_done = false;
712 } while (!err);
713
714 err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
715 if (err)
716 goto drop;
717
718 nf_reset_ct(skb);
719
720 if (decaps) {
721 sp = skb_sec_path(skb);
722 if (sp)
723 sp->olen = 0;
724 if (skb_valid_dst(skb))
725 skb_dst_drop(skb);
726 gro_cells_receive(&gro_cells, skb);
727 return 0;
728 } else {
729 xo = xfrm_offload(skb);
730 if (xo)
731 xfrm_gro = xo->flags & XFRM_GRO;
732
733 err = -EAFNOSUPPORT;
734 rcu_read_lock();
735 afinfo = xfrm_state_afinfo_get_rcu(x->inner_mode.family);
736 if (likely(afinfo))
737 err = afinfo->transport_finish(skb, xfrm_gro || async);
738 rcu_read_unlock();
739 if (xfrm_gro) {
740 sp = skb_sec_path(skb);
741 if (sp)
742 sp->olen = 0;
743 if (skb_valid_dst(skb))
744 skb_dst_drop(skb);
745 gro_cells_receive(&gro_cells, skb);
746 return err;
747 }
748
749 return err;
750 }
751
752 drop_unlock:
753 spin_unlock(&x->lock);
754 drop:
755 xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
756 kfree_skb(skb);
757 return 0;
758 }
759 EXPORT_SYMBOL(xfrm_input);
760
xfrm_input_resume(struct sk_buff * skb,int nexthdr)761 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
762 {
763 return xfrm_input(skb, nexthdr, 0, -1);
764 }
765 EXPORT_SYMBOL(xfrm_input_resume);
766
xfrm_trans_reinject(struct work_struct * work)767 static void xfrm_trans_reinject(struct work_struct *work)
768 {
769 struct xfrm_trans_tasklet *trans = container_of(work, struct xfrm_trans_tasklet, work);
770 struct sk_buff_head queue;
771 struct sk_buff *skb;
772
773 __skb_queue_head_init(&queue);
774 spin_lock_bh(&trans->queue_lock);
775 skb_queue_splice_init(&trans->queue, &queue);
776 spin_unlock_bh(&trans->queue_lock);
777
778 local_bh_disable();
779 while ((skb = __skb_dequeue(&queue)))
780 XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
781 NULL, skb);
782 local_bh_enable();
783 }
784
xfrm_trans_queue_net(struct net * net,struct sk_buff * skb,int (* finish)(struct net *,struct sock *,struct sk_buff *))785 int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
786 int (*finish)(struct net *, struct sock *,
787 struct sk_buff *))
788 {
789 struct xfrm_trans_tasklet *trans;
790
791 trans = this_cpu_ptr(&xfrm_trans_tasklet);
792
793 if (skb_queue_len(&trans->queue) >= READ_ONCE(netdev_max_backlog))
794 return -ENOBUFS;
795
796 BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
797
798 XFRM_TRANS_SKB_CB(skb)->finish = finish;
799 XFRM_TRANS_SKB_CB(skb)->net = net;
800 spin_lock_bh(&trans->queue_lock);
801 __skb_queue_tail(&trans->queue, skb);
802 spin_unlock_bh(&trans->queue_lock);
803 schedule_work(&trans->work);
804 return 0;
805 }
806 EXPORT_SYMBOL(xfrm_trans_queue_net);
807
xfrm_trans_queue(struct sk_buff * skb,int (* finish)(struct net *,struct sock *,struct sk_buff *))808 int xfrm_trans_queue(struct sk_buff *skb,
809 int (*finish)(struct net *, struct sock *,
810 struct sk_buff *))
811 {
812 return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
813 }
814 EXPORT_SYMBOL(xfrm_trans_queue);
815
xfrm_input_init(void)816 void __init xfrm_input_init(void)
817 {
818 int err;
819 int i;
820
821 init_dummy_netdev(&xfrm_napi_dev);
822 err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
823 if (err)
824 gro_cells.cells = NULL;
825
826 for_each_possible_cpu(i) {
827 struct xfrm_trans_tasklet *trans;
828
829 trans = &per_cpu(xfrm_trans_tasklet, i);
830 spin_lock_init(&trans->queue_lock);
831 __skb_queue_head_init(&trans->queue);
832 INIT_WORK(&trans->work, xfrm_trans_reinject);
833 }
834 }
835