GNU Linux-libre 6.1.90-gnu
[releases.git] / net / xfrm / xfrm_input.c
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
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
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
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
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
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         sp->verified_cnt = 0;
135
136         return sp;
137 }
138 EXPORT_SYMBOL(secpath_set);
139
140 /* Fetch spi and seq from ipsec header */
141
142 int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
143 {
144         int offset, offset_seq;
145         int hlen;
146
147         switch (nexthdr) {
148         case IPPROTO_AH:
149                 hlen = sizeof(struct ip_auth_hdr);
150                 offset = offsetof(struct ip_auth_hdr, spi);
151                 offset_seq = offsetof(struct ip_auth_hdr, seq_no);
152                 break;
153         case IPPROTO_ESP:
154                 hlen = sizeof(struct ip_esp_hdr);
155                 offset = offsetof(struct ip_esp_hdr, spi);
156                 offset_seq = offsetof(struct ip_esp_hdr, seq_no);
157                 break;
158         case IPPROTO_COMP:
159                 if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
160                         return -EINVAL;
161                 *spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2)));
162                 *seq = 0;
163                 return 0;
164         default:
165                 return 1;
166         }
167
168         if (!pskb_may_pull(skb, hlen))
169                 return -EINVAL;
170
171         *spi = *(__be32 *)(skb_transport_header(skb) + offset);
172         *seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
173         return 0;
174 }
175 EXPORT_SYMBOL(xfrm_parse_spi);
176
177 static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
178 {
179         struct iphdr *iph;
180         int optlen = 0;
181         int err = -EINVAL;
182
183         skb->protocol = htons(ETH_P_IP);
184
185         if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
186                 struct ip_beet_phdr *ph;
187                 int phlen;
188
189                 if (!pskb_may_pull(skb, sizeof(*ph)))
190                         goto out;
191
192                 ph = (struct ip_beet_phdr *)skb->data;
193
194                 phlen = sizeof(*ph) + ph->padlen;
195                 optlen = ph->hdrlen * 8 + (IPV4_BEET_PHMAXLEN - phlen);
196                 if (optlen < 0 || optlen & 3 || optlen > 250)
197                         goto out;
198
199                 XFRM_MODE_SKB_CB(skb)->protocol = ph->nexthdr;
200
201                 if (!pskb_may_pull(skb, phlen))
202                         goto out;
203                 __skb_pull(skb, phlen);
204         }
205
206         skb_push(skb, sizeof(*iph));
207         skb_reset_network_header(skb);
208         skb_mac_header_rebuild(skb);
209
210         xfrm4_beet_make_header(skb);
211
212         iph = ip_hdr(skb);
213
214         iph->ihl += optlen / 4;
215         iph->tot_len = htons(skb->len);
216         iph->daddr = x->sel.daddr.a4;
217         iph->saddr = x->sel.saddr.a4;
218         iph->check = 0;
219         iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
220         err = 0;
221 out:
222         return err;
223 }
224
225 static void ipip_ecn_decapsulate(struct sk_buff *skb)
226 {
227         struct iphdr *inner_iph = ipip_hdr(skb);
228
229         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
230                 IP_ECN_set_ce(inner_iph);
231 }
232
233 static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
234 {
235         int err = -EINVAL;
236
237         skb->protocol = htons(ETH_P_IP);
238
239         if (!pskb_may_pull(skb, sizeof(struct iphdr)))
240                 goto out;
241
242         err = skb_unclone(skb, GFP_ATOMIC);
243         if (err)
244                 goto out;
245
246         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
247                 ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
248         if (!(x->props.flags & XFRM_STATE_NOECN))
249                 ipip_ecn_decapsulate(skb);
250
251         skb_reset_network_header(skb);
252         skb_mac_header_rebuild(skb);
253         if (skb->mac_len)
254                 eth_hdr(skb)->h_proto = skb->protocol;
255
256         err = 0;
257
258 out:
259         return err;
260 }
261
262 static void ipip6_ecn_decapsulate(struct sk_buff *skb)
263 {
264         struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
265
266         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
267                 IP6_ECN_set_ce(skb, inner_iph);
268 }
269
270 static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
271 {
272         int err = -EINVAL;
273
274         skb->protocol = htons(ETH_P_IPV6);
275
276         if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
277                 goto out;
278
279         err = skb_unclone(skb, GFP_ATOMIC);
280         if (err)
281                 goto out;
282
283         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
284                 ipv6_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipipv6_hdr(skb));
285         if (!(x->props.flags & XFRM_STATE_NOECN))
286                 ipip6_ecn_decapsulate(skb);
287
288         skb_reset_network_header(skb);
289         skb_mac_header_rebuild(skb);
290         if (skb->mac_len)
291                 eth_hdr(skb)->h_proto = skb->protocol;
292
293         err = 0;
294
295 out:
296         return err;
297 }
298
299 static int xfrm6_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
300 {
301         struct ipv6hdr *ip6h;
302         int size = sizeof(struct ipv6hdr);
303         int err;
304
305         skb->protocol = htons(ETH_P_IPV6);
306
307         err = skb_cow_head(skb, size + skb->mac_len);
308         if (err)
309                 goto out;
310
311         __skb_push(skb, size);
312         skb_reset_network_header(skb);
313         skb_mac_header_rebuild(skb);
314
315         xfrm6_beet_make_header(skb);
316
317         ip6h = ipv6_hdr(skb);
318         ip6h->payload_len = htons(skb->len - size);
319         ip6h->daddr = x->sel.daddr.in6;
320         ip6h->saddr = x->sel.saddr.in6;
321         err = 0;
322 out:
323         return err;
324 }
325
326 /* Remove encapsulation header.
327  *
328  * The IP header will be moved over the top of the encapsulation
329  * header.
330  *
331  * On entry, the transport header shall point to where the IP header
332  * should be and the network header shall be set to where the IP
333  * header currently is.  skb->data shall point to the start of the
334  * payload.
335  */
336 static int
337 xfrm_inner_mode_encap_remove(struct xfrm_state *x,
338                              struct sk_buff *skb)
339 {
340         switch (x->props.mode) {
341         case XFRM_MODE_BEET:
342                 switch (x->sel.family) {
343                 case AF_INET:
344                         return xfrm4_remove_beet_encap(x, skb);
345                 case AF_INET6:
346                         return xfrm6_remove_beet_encap(x, skb);
347                 }
348                 break;
349         case XFRM_MODE_TUNNEL:
350                 switch (XFRM_MODE_SKB_CB(skb)->protocol) {
351                 case IPPROTO_IPIP:
352                         return xfrm4_remove_tunnel_encap(x, skb);
353                 case IPPROTO_IPV6:
354                         return xfrm6_remove_tunnel_encap(x, skb);
355                 break;
356                 }
357                 return -EINVAL;
358         }
359
360         WARN_ON_ONCE(1);
361         return -EOPNOTSUPP;
362 }
363
364 static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
365 {
366         switch (x->props.family) {
367         case AF_INET:
368                 xfrm4_extract_header(skb);
369                 break;
370         case AF_INET6:
371                 xfrm6_extract_header(skb);
372                 break;
373         default:
374                 WARN_ON_ONCE(1);
375                 return -EAFNOSUPPORT;
376         }
377
378         return xfrm_inner_mode_encap_remove(x, skb);
379 }
380
381 /* Remove encapsulation header.
382  *
383  * The IP header will be moved over the top of the encapsulation header.
384  *
385  * On entry, skb_transport_header() shall point to where the IP header
386  * should be and skb_network_header() shall be set to where the IP header
387  * currently is.  skb->data shall point to the start of the payload.
388  */
389 static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
390 {
391         int ihl = skb->data - skb_transport_header(skb);
392
393         if (skb->transport_header != skb->network_header) {
394                 memmove(skb_transport_header(skb),
395                         skb_network_header(skb), ihl);
396                 skb->network_header = skb->transport_header;
397         }
398         ip_hdr(skb)->tot_len = htons(skb->len + ihl);
399         skb_reset_transport_header(skb);
400         return 0;
401 }
402
403 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
404 {
405 #if IS_ENABLED(CONFIG_IPV6)
406         int ihl = skb->data - skb_transport_header(skb);
407
408         if (skb->transport_header != skb->network_header) {
409                 memmove(skb_transport_header(skb),
410                         skb_network_header(skb), ihl);
411                 skb->network_header = skb->transport_header;
412         }
413         ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
414                                            sizeof(struct ipv6hdr));
415         skb_reset_transport_header(skb);
416         return 0;
417 #else
418         WARN_ON_ONCE(1);
419         return -EAFNOSUPPORT;
420 #endif
421 }
422
423 static int xfrm_inner_mode_input(struct xfrm_state *x,
424                                  struct sk_buff *skb)
425 {
426         switch (x->props.mode) {
427         case XFRM_MODE_BEET:
428         case XFRM_MODE_TUNNEL:
429                 return xfrm_prepare_input(x, skb);
430         case XFRM_MODE_TRANSPORT:
431                 if (x->props.family == AF_INET)
432                         return xfrm4_transport_input(x, skb);
433                 if (x->props.family == AF_INET6)
434                         return xfrm6_transport_input(x, skb);
435                 break;
436         case XFRM_MODE_ROUTEOPTIMIZATION:
437                 WARN_ON_ONCE(1);
438                 break;
439         default:
440                 WARN_ON_ONCE(1);
441                 break;
442         }
443
444         return -EOPNOTSUPP;
445 }
446
447 int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
448 {
449         const struct xfrm_state_afinfo *afinfo;
450         struct net *net = dev_net(skb->dev);
451         int err;
452         __be32 seq;
453         __be32 seq_hi;
454         struct xfrm_state *x = NULL;
455         xfrm_address_t *daddr;
456         u32 mark = skb->mark;
457         unsigned int family = AF_UNSPEC;
458         int decaps = 0;
459         int async = 0;
460         bool xfrm_gro = false;
461         bool crypto_done = false;
462         struct xfrm_offload *xo = xfrm_offload(skb);
463         struct sec_path *sp;
464
465         if (encap_type < 0) {
466                 x = xfrm_input_state(skb);
467
468                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
469                         if (x->km.state == XFRM_STATE_ACQ)
470                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
471                         else
472                                 XFRM_INC_STATS(net,
473                                                LINUX_MIB_XFRMINSTATEINVALID);
474
475                         if (encap_type == -1)
476                                 dev_put(skb->dev);
477                         goto drop;
478                 }
479
480                 family = x->props.family;
481
482                 /* An encap_type of -1 indicates async resumption. */
483                 if (encap_type == -1) {
484                         async = 1;
485                         seq = XFRM_SKB_CB(skb)->seq.input.low;
486                         goto resume;
487                 }
488
489                 /* encap_type < -1 indicates a GRO call. */
490                 encap_type = 0;
491                 seq = XFRM_SPI_SKB_CB(skb)->seq;
492
493                 if (xo && (xo->flags & CRYPTO_DONE)) {
494                         crypto_done = true;
495                         family = XFRM_SPI_SKB_CB(skb)->family;
496
497                         if (!(xo->status & CRYPTO_SUCCESS)) {
498                                 if (xo->status &
499                                     (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
500                                      CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
501                                      CRYPTO_TUNNEL_AH_AUTH_FAILED |
502                                      CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
503
504                                         xfrm_audit_state_icvfail(x, skb,
505                                                                  x->type->proto);
506                                         x->stats.integrity_failed++;
507                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
508                                         goto drop;
509                                 }
510
511                                 if (xo->status & CRYPTO_INVALID_PROTOCOL) {
512                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
513                                         goto drop;
514                                 }
515
516                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
517                                 goto drop;
518                         }
519
520                         if (xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
521                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
522                                 goto drop;
523                         }
524                 }
525
526                 goto lock;
527         }
528
529         family = XFRM_SPI_SKB_CB(skb)->family;
530
531         /* if tunnel is present override skb->mark value with tunnel i_key */
532         switch (family) {
533         case AF_INET:
534                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
535                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
536                 break;
537         case AF_INET6:
538                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
539                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
540                 break;
541         }
542
543         sp = secpath_set(skb);
544         if (!sp) {
545                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
546                 goto drop;
547         }
548
549         seq = 0;
550         if (!spi && xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
551                 secpath_reset(skb);
552                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
553                 goto drop;
554         }
555
556         daddr = (xfrm_address_t *)(skb_network_header(skb) +
557                                    XFRM_SPI_SKB_CB(skb)->daddroff);
558         do {
559                 sp = skb_sec_path(skb);
560
561                 if (sp->len == XFRM_MAX_DEPTH) {
562                         secpath_reset(skb);
563                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
564                         goto drop;
565                 }
566
567                 x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
568                 if (x == NULL) {
569                         secpath_reset(skb);
570                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
571                         xfrm_audit_state_notfound(skb, family, spi, seq);
572                         goto drop;
573                 }
574
575                 skb->mark = xfrm_smark_get(skb->mark, x);
576
577                 sp->xvec[sp->len++] = x;
578
579                 skb_dst_force(skb);
580                 if (!skb_dst(skb)) {
581                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
582                         goto drop;
583                 }
584
585 lock:
586                 spin_lock(&x->lock);
587
588                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
589                         if (x->km.state == XFRM_STATE_ACQ)
590                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
591                         else
592                                 XFRM_INC_STATS(net,
593                                                LINUX_MIB_XFRMINSTATEINVALID);
594                         goto drop_unlock;
595                 }
596
597                 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
598                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
599                         goto drop_unlock;
600                 }
601
602                 if (xfrm_replay_check(x, skb, seq)) {
603                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
604                         goto drop_unlock;
605                 }
606
607                 if (xfrm_state_check_expire(x)) {
608                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
609                         goto drop_unlock;
610                 }
611
612                 spin_unlock(&x->lock);
613
614                 if (xfrm_tunnel_check(skb, x, family)) {
615                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
616                         goto drop;
617                 }
618
619                 seq_hi = htonl(xfrm_replay_seqhi(x, seq));
620
621                 XFRM_SKB_CB(skb)->seq.input.low = seq;
622                 XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
623
624                 dev_hold(skb->dev);
625
626                 if (crypto_done)
627                         nexthdr = x->type_offload->input_tail(x, skb);
628                 else
629                         nexthdr = x->type->input(x, skb);
630
631                 if (nexthdr == -EINPROGRESS)
632                         return 0;
633 resume:
634                 dev_put(skb->dev);
635
636                 spin_lock(&x->lock);
637                 if (nexthdr < 0) {
638                         if (nexthdr == -EBADMSG) {
639                                 xfrm_audit_state_icvfail(x, skb,
640                                                          x->type->proto);
641                                 x->stats.integrity_failed++;
642                         }
643                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
644                         goto drop_unlock;
645                 }
646
647                 /* only the first xfrm gets the encap type */
648                 encap_type = 0;
649
650                 if (xfrm_replay_recheck(x, skb, seq)) {
651                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
652                         goto drop_unlock;
653                 }
654
655                 xfrm_replay_advance(x, seq);
656
657                 x->curlft.bytes += skb->len;
658                 x->curlft.packets++;
659
660                 spin_unlock(&x->lock);
661
662                 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
663
664                 if (xfrm_inner_mode_input(x, skb)) {
665                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
666                         goto drop;
667                 }
668
669                 if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
670                         decaps = 1;
671                         break;
672                 }
673
674                 /*
675                  * We need the inner address.  However, we only get here for
676                  * transport mode so the outer address is identical.
677                  */
678                 daddr = &x->id.daddr;
679                 family = x->props.family;
680
681                 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
682                 if (err < 0) {
683                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
684                         goto drop;
685                 }
686                 crypto_done = false;
687         } while (!err);
688
689         err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
690         if (err)
691                 goto drop;
692
693         nf_reset_ct(skb);
694
695         if (decaps) {
696                 sp = skb_sec_path(skb);
697                 if (sp)
698                         sp->olen = 0;
699                 if (skb_valid_dst(skb))
700                         skb_dst_drop(skb);
701                 gro_cells_receive(&gro_cells, skb);
702                 return 0;
703         } else {
704                 xo = xfrm_offload(skb);
705                 if (xo)
706                         xfrm_gro = xo->flags & XFRM_GRO;
707
708                 err = -EAFNOSUPPORT;
709                 rcu_read_lock();
710                 afinfo = xfrm_state_afinfo_get_rcu(x->props.family);
711                 if (likely(afinfo))
712                         err = afinfo->transport_finish(skb, xfrm_gro || async);
713                 rcu_read_unlock();
714                 if (xfrm_gro) {
715                         sp = skb_sec_path(skb);
716                         if (sp)
717                                 sp->olen = 0;
718                         if (skb_valid_dst(skb))
719                                 skb_dst_drop(skb);
720                         gro_cells_receive(&gro_cells, skb);
721                         return err;
722                 }
723
724                 return err;
725         }
726
727 drop_unlock:
728         spin_unlock(&x->lock);
729 drop:
730         xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
731         kfree_skb(skb);
732         return 0;
733 }
734 EXPORT_SYMBOL(xfrm_input);
735
736 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
737 {
738         return xfrm_input(skb, nexthdr, 0, -1);
739 }
740 EXPORT_SYMBOL(xfrm_input_resume);
741
742 static void xfrm_trans_reinject(struct work_struct *work)
743 {
744         struct xfrm_trans_tasklet *trans = container_of(work, struct xfrm_trans_tasklet, work);
745         struct sk_buff_head queue;
746         struct sk_buff *skb;
747
748         __skb_queue_head_init(&queue);
749         spin_lock_bh(&trans->queue_lock);
750         skb_queue_splice_init(&trans->queue, &queue);
751         spin_unlock_bh(&trans->queue_lock);
752
753         local_bh_disable();
754         while ((skb = __skb_dequeue(&queue)))
755                 XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
756                                                NULL, skb);
757         local_bh_enable();
758 }
759
760 int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
761                          int (*finish)(struct net *, struct sock *,
762                                        struct sk_buff *))
763 {
764         struct xfrm_trans_tasklet *trans;
765
766         trans = this_cpu_ptr(&xfrm_trans_tasklet);
767
768         if (skb_queue_len(&trans->queue) >= READ_ONCE(netdev_max_backlog))
769                 return -ENOBUFS;
770
771         BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
772
773         XFRM_TRANS_SKB_CB(skb)->finish = finish;
774         XFRM_TRANS_SKB_CB(skb)->net = net;
775         spin_lock_bh(&trans->queue_lock);
776         __skb_queue_tail(&trans->queue, skb);
777         spin_unlock_bh(&trans->queue_lock);
778         schedule_work(&trans->work);
779         return 0;
780 }
781 EXPORT_SYMBOL(xfrm_trans_queue_net);
782
783 int xfrm_trans_queue(struct sk_buff *skb,
784                      int (*finish)(struct net *, struct sock *,
785                                    struct sk_buff *))
786 {
787         return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
788 }
789 EXPORT_SYMBOL(xfrm_trans_queue);
790
791 void __init xfrm_input_init(void)
792 {
793         int err;
794         int i;
795
796         init_dummy_netdev(&xfrm_napi_dev);
797         err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
798         if (err)
799                 gro_cells.cells = NULL;
800
801         for_each_possible_cpu(i) {
802                 struct xfrm_trans_tasklet *trans;
803
804                 trans = &per_cpu(xfrm_trans_tasklet, i);
805                 spin_lock_init(&trans->queue_lock);
806                 __skb_queue_head_init(&trans->queue);
807                 INIT_WORK(&trans->work, xfrm_trans_reinject);
808         }
809 }