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
24 #include "xfrm_inout.h"
25
26 struct xfrm_trans_tasklet {
27 struct tasklet_struct tasklet;
28 struct sk_buff_head queue;
29 };
30
31 struct xfrm_trans_cb {
32 union {
33 struct inet_skb_parm h4;
34 #if IS_ENABLED(CONFIG_IPV6)
35 struct inet6_skb_parm h6;
36 #endif
37 } header;
38 int (*finish)(struct net *net, struct sock *sk, struct sk_buff *skb);
39 struct net *net;
40 };
41
42 #define XFRM_TRANS_SKB_CB(__skb) ((struct xfrm_trans_cb *)&((__skb)->cb[0]))
43
44 static DEFINE_SPINLOCK(xfrm_input_afinfo_lock);
45 static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[2][AF_INET6 + 1];
46
47 static struct gro_cells gro_cells;
48 static struct net_device xfrm_napi_dev;
49
50 static DEFINE_PER_CPU(struct xfrm_trans_tasklet, xfrm_trans_tasklet);
51
xfrm_input_register_afinfo(const struct xfrm_input_afinfo * afinfo)52 int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo)
53 {
54 int err = 0;
55
56 if (WARN_ON(afinfo->family > AF_INET6))
57 return -EAFNOSUPPORT;
58
59 spin_lock_bh(&xfrm_input_afinfo_lock);
60 if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family]))
61 err = -EEXIST;
62 else
63 rcu_assign_pointer(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], afinfo);
64 spin_unlock_bh(&xfrm_input_afinfo_lock);
65 return err;
66 }
67 EXPORT_SYMBOL(xfrm_input_register_afinfo);
68
xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo * afinfo)69 int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo)
70 {
71 int err = 0;
72
73 spin_lock_bh(&xfrm_input_afinfo_lock);
74 if (likely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family])) {
75 if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family] != afinfo))
76 err = -EINVAL;
77 else
78 RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], NULL);
79 }
80 spin_unlock_bh(&xfrm_input_afinfo_lock);
81 synchronize_rcu();
82 return err;
83 }
84 EXPORT_SYMBOL(xfrm_input_unregister_afinfo);
85
xfrm_input_get_afinfo(u8 family,bool is_ipip)86 static const struct xfrm_input_afinfo *xfrm_input_get_afinfo(u8 family, bool is_ipip)
87 {
88 const struct xfrm_input_afinfo *afinfo;
89
90 if (WARN_ON_ONCE(family > AF_INET6))
91 return NULL;
92
93 rcu_read_lock();
94 afinfo = rcu_dereference(xfrm_input_afinfo[is_ipip][family]);
95 if (unlikely(!afinfo))
96 rcu_read_unlock();
97 return afinfo;
98 }
99
xfrm_rcv_cb(struct sk_buff * skb,unsigned int family,u8 protocol,int err)100 static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
101 int err)
102 {
103 bool is_ipip = (protocol == IPPROTO_IPIP || protocol == IPPROTO_IPV6);
104 const struct xfrm_input_afinfo *afinfo;
105 int ret;
106
107 afinfo = xfrm_input_get_afinfo(family, is_ipip);
108 if (!afinfo)
109 return -EAFNOSUPPORT;
110
111 ret = afinfo->callback(skb, protocol, err);
112 rcu_read_unlock();
113
114 return ret;
115 }
116
secpath_set(struct sk_buff * skb)117 struct sec_path *secpath_set(struct sk_buff *skb)
118 {
119 struct sec_path *sp, *tmp = skb_ext_find(skb, SKB_EXT_SEC_PATH);
120
121 sp = skb_ext_add(skb, SKB_EXT_SEC_PATH);
122 if (!sp)
123 return NULL;
124
125 if (tmp) /* reused existing one (was COW'd if needed) */
126 return sp;
127
128 /* allocated new secpath */
129 memset(sp->ovec, 0, sizeof(sp->ovec));
130 sp->olen = 0;
131 sp->len = 0;
132 sp->verified_cnt = 0;
133
134 return sp;
135 }
136 EXPORT_SYMBOL(secpath_set);
137
138 /* Fetch spi and seq from ipsec header */
139
xfrm_parse_spi(struct sk_buff * skb,u8 nexthdr,__be32 * spi,__be32 * seq)140 int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
141 {
142 int offset, offset_seq;
143 int hlen;
144
145 switch (nexthdr) {
146 case IPPROTO_AH:
147 hlen = sizeof(struct ip_auth_hdr);
148 offset = offsetof(struct ip_auth_hdr, spi);
149 offset_seq = offsetof(struct ip_auth_hdr, seq_no);
150 break;
151 case IPPROTO_ESP:
152 hlen = sizeof(struct ip_esp_hdr);
153 offset = offsetof(struct ip_esp_hdr, spi);
154 offset_seq = offsetof(struct ip_esp_hdr, seq_no);
155 break;
156 case IPPROTO_COMP:
157 if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
158 return -EINVAL;
159 *spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2)));
160 *seq = 0;
161 return 0;
162 default:
163 return 1;
164 }
165
166 if (!pskb_may_pull(skb, hlen))
167 return -EINVAL;
168
169 *spi = *(__be32 *)(skb_transport_header(skb) + offset);
170 *seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
171 return 0;
172 }
173 EXPORT_SYMBOL(xfrm_parse_spi);
174
xfrm4_remove_beet_encap(struct xfrm_state * x,struct sk_buff * skb)175 static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
176 {
177 struct iphdr *iph;
178 int optlen = 0;
179 int err = -EINVAL;
180
181 if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
182 struct ip_beet_phdr *ph;
183 int phlen;
184
185 if (!pskb_may_pull(skb, sizeof(*ph)))
186 goto out;
187
188 ph = (struct ip_beet_phdr *)skb->data;
189
190 phlen = sizeof(*ph) + ph->padlen;
191 optlen = ph->hdrlen * 8 + (IPV4_BEET_PHMAXLEN - phlen);
192 if (optlen < 0 || optlen & 3 || optlen > 250)
193 goto out;
194
195 XFRM_MODE_SKB_CB(skb)->protocol = ph->nexthdr;
196
197 if (!pskb_may_pull(skb, phlen))
198 goto out;
199 __skb_pull(skb, phlen);
200 }
201
202 skb_push(skb, sizeof(*iph));
203 skb_reset_network_header(skb);
204 skb_mac_header_rebuild(skb);
205
206 xfrm4_beet_make_header(skb);
207
208 iph = ip_hdr(skb);
209
210 iph->ihl += optlen / 4;
211 iph->tot_len = htons(skb->len);
212 iph->daddr = x->sel.daddr.a4;
213 iph->saddr = x->sel.saddr.a4;
214 iph->check = 0;
215 iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
216 err = 0;
217 out:
218 return err;
219 }
220
ipip_ecn_decapsulate(struct sk_buff * skb)221 static void ipip_ecn_decapsulate(struct sk_buff *skb)
222 {
223 struct iphdr *inner_iph = ipip_hdr(skb);
224
225 if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
226 IP_ECN_set_ce(inner_iph);
227 }
228
xfrm4_remove_tunnel_encap(struct xfrm_state * x,struct sk_buff * skb)229 static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
230 {
231 int err = -EINVAL;
232
233 if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
234 goto out;
235
236 if (!pskb_may_pull(skb, sizeof(struct iphdr)))
237 goto out;
238
239 err = skb_unclone(skb, GFP_ATOMIC);
240 if (err)
241 goto out;
242
243 if (x->props.flags & XFRM_STATE_DECAP_DSCP)
244 ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
245 if (!(x->props.flags & XFRM_STATE_NOECN))
246 ipip_ecn_decapsulate(skb);
247
248 skb_reset_network_header(skb);
249 skb_mac_header_rebuild(skb);
250 if (skb->mac_len)
251 eth_hdr(skb)->h_proto = skb->protocol;
252
253 err = 0;
254
255 out:
256 return err;
257 }
258
ipip6_ecn_decapsulate(struct sk_buff * skb)259 static void ipip6_ecn_decapsulate(struct sk_buff *skb)
260 {
261 struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
262
263 if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
264 IP6_ECN_set_ce(skb, inner_iph);
265 }
266
xfrm6_remove_tunnel_encap(struct xfrm_state * x,struct sk_buff * skb)267 static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
268 {
269 int err = -EINVAL;
270
271 if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
272 goto out;
273 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
274 goto out;
275
276 err = skb_unclone(skb, GFP_ATOMIC);
277 if (err)
278 goto out;
279
280 if (x->props.flags & XFRM_STATE_DECAP_DSCP)
281 ipv6_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipipv6_hdr(skb));
282 if (!(x->props.flags & XFRM_STATE_NOECN))
283 ipip6_ecn_decapsulate(skb);
284
285 skb_reset_network_header(skb);
286 skb_mac_header_rebuild(skb);
287 if (skb->mac_len)
288 eth_hdr(skb)->h_proto = skb->protocol;
289
290 err = 0;
291
292 out:
293 return err;
294 }
295
xfrm6_remove_beet_encap(struct xfrm_state * x,struct sk_buff * skb)296 static int xfrm6_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
297 {
298 struct ipv6hdr *ip6h;
299 int size = sizeof(struct ipv6hdr);
300 int err;
301
302 err = skb_cow_head(skb, size + skb->mac_len);
303 if (err)
304 goto out;
305
306 __skb_push(skb, size);
307 skb_reset_network_header(skb);
308 skb_mac_header_rebuild(skb);
309
310 xfrm6_beet_make_header(skb);
311
312 ip6h = ipv6_hdr(skb);
313 ip6h->payload_len = htons(skb->len - size);
314 ip6h->daddr = x->sel.daddr.in6;
315 ip6h->saddr = x->sel.saddr.in6;
316 err = 0;
317 out:
318 return err;
319 }
320
321 /* Remove encapsulation header.
322 *
323 * The IP header will be moved over the top of the encapsulation
324 * header.
325 *
326 * On entry, the transport header shall point to where the IP header
327 * should be and the network header shall be set to where the IP
328 * header currently is. skb->data shall point to the start of the
329 * payload.
330 */
331 static int
xfrm_inner_mode_encap_remove(struct xfrm_state * x,const struct xfrm_mode * inner_mode,struct sk_buff * skb)332 xfrm_inner_mode_encap_remove(struct xfrm_state *x,
333 const struct xfrm_mode *inner_mode,
334 struct sk_buff *skb)
335 {
336 switch (inner_mode->encap) {
337 case XFRM_MODE_BEET:
338 if (inner_mode->family == AF_INET)
339 return xfrm4_remove_beet_encap(x, skb);
340 if (inner_mode->family == AF_INET6)
341 return xfrm6_remove_beet_encap(x, skb);
342 break;
343 case XFRM_MODE_TUNNEL:
344 if (inner_mode->family == AF_INET)
345 return xfrm4_remove_tunnel_encap(x, skb);
346 if (inner_mode->family == AF_INET6)
347 return xfrm6_remove_tunnel_encap(x, skb);
348 break;
349 }
350
351 WARN_ON_ONCE(1);
352 return -EOPNOTSUPP;
353 }
354
xfrm_prepare_input(struct xfrm_state * x,struct sk_buff * skb)355 static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
356 {
357 const struct xfrm_mode *inner_mode = &x->inner_mode;
358
359 switch (x->outer_mode.family) {
360 case AF_INET:
361 xfrm4_extract_header(skb);
362 break;
363 case AF_INET6:
364 xfrm6_extract_header(skb);
365 break;
366 default:
367 WARN_ON_ONCE(1);
368 return -EAFNOSUPPORT;
369 }
370
371 if (x->sel.family == AF_UNSPEC) {
372 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
373 if (!inner_mode)
374 return -EAFNOSUPPORT;
375 }
376
377 switch (inner_mode->family) {
378 case AF_INET:
379 skb->protocol = htons(ETH_P_IP);
380 break;
381 case AF_INET6:
382 skb->protocol = htons(ETH_P_IPV6);
383 break;
384 default:
385 WARN_ON_ONCE(1);
386 break;
387 }
388
389 return xfrm_inner_mode_encap_remove(x, inner_mode, skb);
390 }
391
392 /* Remove encapsulation header.
393 *
394 * The IP header will be moved over the top of the encapsulation header.
395 *
396 * On entry, skb_transport_header() shall point to where the IP header
397 * should be and skb_network_header() shall be set to where the IP header
398 * currently is. skb->data shall point to the start of the payload.
399 */
xfrm4_transport_input(struct xfrm_state * x,struct sk_buff * skb)400 static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
401 {
402 int ihl = skb->data - skb_transport_header(skb);
403
404 if (skb->transport_header != skb->network_header) {
405 memmove(skb_transport_header(skb),
406 skb_network_header(skb), ihl);
407 skb->network_header = skb->transport_header;
408 }
409 ip_hdr(skb)->tot_len = htons(skb->len + ihl);
410 skb_reset_transport_header(skb);
411 return 0;
412 }
413
xfrm6_transport_input(struct xfrm_state * x,struct sk_buff * skb)414 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
415 {
416 #if IS_ENABLED(CONFIG_IPV6)
417 int ihl = skb->data - skb_transport_header(skb);
418
419 if (skb->transport_header != skb->network_header) {
420 memmove(skb_transport_header(skb),
421 skb_network_header(skb), ihl);
422 skb->network_header = skb->transport_header;
423 }
424 ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
425 sizeof(struct ipv6hdr));
426 skb_reset_transport_header(skb);
427 return 0;
428 #else
429 WARN_ON_ONCE(1);
430 return -EAFNOSUPPORT;
431 #endif
432 }
433
xfrm_inner_mode_input(struct xfrm_state * x,const struct xfrm_mode * inner_mode,struct sk_buff * skb)434 static int xfrm_inner_mode_input(struct xfrm_state *x,
435 const struct xfrm_mode *inner_mode,
436 struct sk_buff *skb)
437 {
438 switch (inner_mode->encap) {
439 case XFRM_MODE_BEET:
440 case XFRM_MODE_TUNNEL:
441 return xfrm_prepare_input(x, skb);
442 case XFRM_MODE_TRANSPORT:
443 if (inner_mode->family == AF_INET)
444 return xfrm4_transport_input(x, skb);
445 if (inner_mode->family == AF_INET6)
446 return xfrm6_transport_input(x, skb);
447 break;
448 case XFRM_MODE_ROUTEOPTIMIZATION:
449 WARN_ON_ONCE(1);
450 break;
451 default:
452 WARN_ON_ONCE(1);
453 break;
454 }
455
456 return -EOPNOTSUPP;
457 }
458
xfrm_input(struct sk_buff * skb,int nexthdr,__be32 spi,int encap_type)459 int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
460 {
461 const struct xfrm_state_afinfo *afinfo;
462 struct net *net = dev_net(skb->dev);
463 const struct xfrm_mode *inner_mode;
464 int err;
465 __be32 seq;
466 __be32 seq_hi;
467 struct xfrm_state *x = NULL;
468 xfrm_address_t *daddr;
469 u32 mark = skb->mark;
470 unsigned int family = AF_UNSPEC;
471 int decaps = 0;
472 int async = 0;
473 bool xfrm_gro = false;
474 bool crypto_done = false;
475 struct xfrm_offload *xo = xfrm_offload(skb);
476 struct sec_path *sp;
477
478 if (encap_type < 0) {
479 x = xfrm_input_state(skb);
480
481 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
482 if (x->km.state == XFRM_STATE_ACQ)
483 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
484 else
485 XFRM_INC_STATS(net,
486 LINUX_MIB_XFRMINSTATEINVALID);
487
488 if (encap_type == -1)
489 dev_put(skb->dev);
490 goto drop;
491 }
492
493 family = x->outer_mode.family;
494
495 /* An encap_type of -1 indicates async resumption. */
496 if (encap_type == -1) {
497 async = 1;
498 seq = XFRM_SKB_CB(skb)->seq.input.low;
499 goto resume;
500 }
501
502 /* encap_type < -1 indicates a GRO call. */
503 encap_type = 0;
504 seq = XFRM_SPI_SKB_CB(skb)->seq;
505
506 if (xo && (xo->flags & CRYPTO_DONE)) {
507 crypto_done = true;
508 family = XFRM_SPI_SKB_CB(skb)->family;
509
510 if (!(xo->status & CRYPTO_SUCCESS)) {
511 if (xo->status &
512 (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
513 CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
514 CRYPTO_TUNNEL_AH_AUTH_FAILED |
515 CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
516
517 xfrm_audit_state_icvfail(x, skb,
518 x->type->proto);
519 x->stats.integrity_failed++;
520 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
521 goto drop;
522 }
523
524 if (xo->status & CRYPTO_INVALID_PROTOCOL) {
525 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
526 goto drop;
527 }
528
529 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
530 goto drop;
531 }
532
533 if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
534 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
535 goto drop;
536 }
537 }
538
539 goto lock;
540 }
541
542 family = XFRM_SPI_SKB_CB(skb)->family;
543
544 /* if tunnel is present override skb->mark value with tunnel i_key */
545 switch (family) {
546 case AF_INET:
547 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
548 mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
549 break;
550 case AF_INET6:
551 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
552 mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
553 break;
554 }
555
556 sp = secpath_set(skb);
557 if (!sp) {
558 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
559 goto drop;
560 }
561
562 seq = 0;
563 if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
564 secpath_reset(skb);
565 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
566 goto drop;
567 }
568
569 daddr = (xfrm_address_t *)(skb_network_header(skb) +
570 XFRM_SPI_SKB_CB(skb)->daddroff);
571 do {
572 sp = skb_sec_path(skb);
573
574 if (sp->len == XFRM_MAX_DEPTH) {
575 secpath_reset(skb);
576 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
577 goto drop;
578 }
579
580 x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
581 if (x == NULL) {
582 secpath_reset(skb);
583 XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
584 xfrm_audit_state_notfound(skb, family, spi, seq);
585 goto drop;
586 }
587
588 /* If nested tunnel, check outer states before context is lost.
589 * Only nested tunnels need to be checked, since IP addresses change
590 * as a result of the tunnel mode decapsulation. Similarly, this check
591 * is limited to nested tunnels to avoid performing another policy
592 * check on non-nested tunnels. On success, this check also updates the
593 * secpath's verified_cnt variable, skipping future verifications of
594 * previously-verified secpath entries.
595 */
596 if ((x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) &&
597 sp->verified_cnt < sp->len &&
598 !xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family)) {
599 goto drop;
600 }
601
602 skb->mark = xfrm_smark_get(skb->mark, x);
603
604 sp->xvec[sp->len++] = x;
605
606 skb_dst_force(skb);
607 if (!skb_dst(skb)) {
608 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
609 goto drop;
610 }
611
612 lock:
613 spin_lock(&x->lock);
614
615 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
616 if (x->km.state == XFRM_STATE_ACQ)
617 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
618 else
619 XFRM_INC_STATS(net,
620 LINUX_MIB_XFRMINSTATEINVALID);
621 goto drop_unlock;
622 }
623
624 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
625 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
626 goto drop_unlock;
627 }
628
629 if (x->repl->check(x, skb, seq)) {
630 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
631 goto drop_unlock;
632 }
633
634 if (xfrm_state_check_expire(x)) {
635 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
636 goto drop_unlock;
637 }
638
639 spin_unlock(&x->lock);
640
641 if (xfrm_tunnel_check(skb, x, family)) {
642 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
643 goto drop;
644 }
645
646 seq_hi = htonl(xfrm_replay_seqhi(x, seq));
647
648 XFRM_SKB_CB(skb)->seq.input.low = seq;
649 XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
650
651 dev_hold(skb->dev);
652
653 if (crypto_done)
654 nexthdr = x->type_offload->input_tail(x, skb);
655 else
656 nexthdr = x->type->input(x, skb);
657
658 if (nexthdr == -EINPROGRESS)
659 return 0;
660 resume:
661 dev_put(skb->dev);
662
663 spin_lock(&x->lock);
664 if (nexthdr < 0) {
665 if (nexthdr == -EBADMSG) {
666 xfrm_audit_state_icvfail(x, skb,
667 x->type->proto);
668 x->stats.integrity_failed++;
669 }
670 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
671 goto drop_unlock;
672 }
673
674 /* only the first xfrm gets the encap type */
675 encap_type = 0;
676
677 if (x->repl->recheck(x, skb, seq)) {
678 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
679 goto drop_unlock;
680 }
681
682 x->repl->advance(x, seq);
683
684 x->curlft.bytes += skb->len;
685 x->curlft.packets++;
686
687 spin_unlock(&x->lock);
688
689 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
690
691 inner_mode = &x->inner_mode;
692
693 if (x->sel.family == AF_UNSPEC) {
694 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
695 if (inner_mode == NULL) {
696 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
697 goto drop;
698 }
699 }
700
701 if (xfrm_inner_mode_input(x, inner_mode, skb)) {
702 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
703 goto drop;
704 }
705
706 if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
707 decaps = 1;
708 break;
709 }
710
711 /*
712 * We need the inner address. However, we only get here for
713 * transport mode so the outer address is identical.
714 */
715 daddr = &x->id.daddr;
716 family = x->outer_mode.family;
717
718 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
719 if (err < 0) {
720 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
721 goto drop;
722 }
723 crypto_done = false;
724 } while (!err);
725
726 err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
727 if (err)
728 goto drop;
729
730 nf_reset_ct(skb);
731
732 if (decaps) {
733 sp = skb_sec_path(skb);
734 if (sp)
735 sp->olen = 0;
736 skb_dst_drop(skb);
737 gro_cells_receive(&gro_cells, skb);
738 return 0;
739 } else {
740 xo = xfrm_offload(skb);
741 if (xo)
742 xfrm_gro = xo->flags & XFRM_GRO;
743
744 err = -EAFNOSUPPORT;
745 rcu_read_lock();
746 afinfo = xfrm_state_afinfo_get_rcu(x->inner_mode.family);
747 if (likely(afinfo))
748 err = afinfo->transport_finish(skb, xfrm_gro || async);
749 rcu_read_unlock();
750 if (xfrm_gro) {
751 sp = skb_sec_path(skb);
752 if (sp)
753 sp->olen = 0;
754 skb_dst_drop(skb);
755 gro_cells_receive(&gro_cells, skb);
756 return err;
757 }
758
759 return err;
760 }
761
762 drop_unlock:
763 spin_unlock(&x->lock);
764 drop:
765 xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
766 kfree_skb(skb);
767 return 0;
768 }
769 EXPORT_SYMBOL(xfrm_input);
770
xfrm_input_resume(struct sk_buff * skb,int nexthdr)771 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
772 {
773 return xfrm_input(skb, nexthdr, 0, -1);
774 }
775 EXPORT_SYMBOL(xfrm_input_resume);
776
xfrm_trans_reinject(unsigned long data)777 static void xfrm_trans_reinject(unsigned long data)
778 {
779 struct xfrm_trans_tasklet *trans = (void *)data;
780 struct sk_buff_head queue;
781 struct sk_buff *skb;
782
783 __skb_queue_head_init(&queue);
784 skb_queue_splice_init(&trans->queue, &queue);
785
786 while ((skb = __skb_dequeue(&queue)))
787 XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
788 NULL, skb);
789 }
790
xfrm_trans_queue_net(struct net * net,struct sk_buff * skb,int (* finish)(struct net *,struct sock *,struct sk_buff *))791 int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
792 int (*finish)(struct net *, struct sock *,
793 struct sk_buff *))
794 {
795 struct xfrm_trans_tasklet *trans;
796
797 trans = this_cpu_ptr(&xfrm_trans_tasklet);
798
799 if (skb_queue_len(&trans->queue) >= READ_ONCE(netdev_max_backlog))
800 return -ENOBUFS;
801
802 BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
803
804 XFRM_TRANS_SKB_CB(skb)->finish = finish;
805 XFRM_TRANS_SKB_CB(skb)->net = net;
806 __skb_queue_tail(&trans->queue, skb);
807 tasklet_schedule(&trans->tasklet);
808 return 0;
809 }
810 EXPORT_SYMBOL(xfrm_trans_queue_net);
811
xfrm_trans_queue(struct sk_buff * skb,int (* finish)(struct net *,struct sock *,struct sk_buff *))812 int xfrm_trans_queue(struct sk_buff *skb,
813 int (*finish)(struct net *, struct sock *,
814 struct sk_buff *))
815 {
816 return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
817 }
818 EXPORT_SYMBOL(xfrm_trans_queue);
819
xfrm_input_init(void)820 void __init xfrm_input_init(void)
821 {
822 int err;
823 int i;
824
825 init_dummy_netdev(&xfrm_napi_dev);
826 err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
827 if (err)
828 gro_cells.cells = NULL;
829
830 for_each_possible_cpu(i) {
831 struct xfrm_trans_tasklet *trans;
832
833 trans = &per_cpu(xfrm_trans_tasklet, i);
834 __skb_queue_head_init(&trans->queue);
835 tasklet_init(&trans->tasklet, xfrm_trans_reinject,
836 (unsigned long)trans);
837 }
838 }
839