GNU Linux-libre 6.8.9-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 || (xo && xo->flags & XFRM_GRO)) {
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                 /* GRO call */
489                 seq = XFRM_SPI_SKB_CB(skb)->seq;
490
491                 if (xo && (xo->flags & CRYPTO_DONE)) {
492                         crypto_done = true;
493                         family = XFRM_SPI_SKB_CB(skb)->family;
494
495                         if (!(xo->status & CRYPTO_SUCCESS)) {
496                                 if (xo->status &
497                                     (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
498                                      CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
499                                      CRYPTO_TUNNEL_AH_AUTH_FAILED |
500                                      CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
501
502                                         xfrm_audit_state_icvfail(x, skb,
503                                                                  x->type->proto);
504                                         x->stats.integrity_failed++;
505                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
506                                         goto drop;
507                                 }
508
509                                 if (xo->status & CRYPTO_INVALID_PROTOCOL) {
510                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
511                                         goto drop;
512                                 }
513
514                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
515                                 goto drop;
516                         }
517
518                         if (xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
519                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
520                                 goto drop;
521                         }
522                 }
523
524                 goto lock;
525         }
526
527         family = XFRM_SPI_SKB_CB(skb)->family;
528
529         /* if tunnel is present override skb->mark value with tunnel i_key */
530         switch (family) {
531         case AF_INET:
532                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
533                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
534                 break;
535         case AF_INET6:
536                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
537                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
538                 break;
539         }
540
541         sp = secpath_set(skb);
542         if (!sp) {
543                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
544                 goto drop;
545         }
546
547         seq = 0;
548         if (!spi && xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
549                 secpath_reset(skb);
550                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
551                 goto drop;
552         }
553
554         daddr = (xfrm_address_t *)(skb_network_header(skb) +
555                                    XFRM_SPI_SKB_CB(skb)->daddroff);
556         do {
557                 sp = skb_sec_path(skb);
558
559                 if (sp->len == XFRM_MAX_DEPTH) {
560                         secpath_reset(skb);
561                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
562                         goto drop;
563                 }
564
565                 x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
566                 if (x == NULL) {
567                         secpath_reset(skb);
568                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
569                         xfrm_audit_state_notfound(skb, family, spi, seq);
570                         goto drop;
571                 }
572
573                 skb->mark = xfrm_smark_get(skb->mark, x);
574
575                 sp->xvec[sp->len++] = x;
576
577                 skb_dst_force(skb);
578                 if (!skb_dst(skb)) {
579                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
580                         goto drop;
581                 }
582
583 lock:
584                 spin_lock(&x->lock);
585
586                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
587                         if (x->km.state == XFRM_STATE_ACQ)
588                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
589                         else
590                                 XFRM_INC_STATS(net,
591                                                LINUX_MIB_XFRMINSTATEINVALID);
592                         goto drop_unlock;
593                 }
594
595                 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
596                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
597                         goto drop_unlock;
598                 }
599
600                 if (xfrm_replay_check(x, skb, seq)) {
601                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
602                         goto drop_unlock;
603                 }
604
605                 if (xfrm_state_check_expire(x)) {
606                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
607                         goto drop_unlock;
608                 }
609
610                 spin_unlock(&x->lock);
611
612                 if (xfrm_tunnel_check(skb, x, family)) {
613                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
614                         goto drop;
615                 }
616
617                 seq_hi = htonl(xfrm_replay_seqhi(x, seq));
618
619                 XFRM_SKB_CB(skb)->seq.input.low = seq;
620                 XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
621
622                 dev_hold(skb->dev);
623
624                 if (crypto_done)
625                         nexthdr = x->type_offload->input_tail(x, skb);
626                 else
627                         nexthdr = x->type->input(x, skb);
628
629                 if (nexthdr == -EINPROGRESS)
630                         return 0;
631 resume:
632                 dev_put(skb->dev);
633
634                 spin_lock(&x->lock);
635                 if (nexthdr < 0) {
636                         if (nexthdr == -EBADMSG) {
637                                 xfrm_audit_state_icvfail(x, skb,
638                                                          x->type->proto);
639                                 x->stats.integrity_failed++;
640                         }
641                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
642                         goto drop_unlock;
643                 }
644
645                 /* only the first xfrm gets the encap type */
646                 encap_type = 0;
647
648                 if (xfrm_replay_recheck(x, skb, seq)) {
649                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
650                         goto drop_unlock;
651                 }
652
653                 xfrm_replay_advance(x, seq);
654
655                 x->curlft.bytes += skb->len;
656                 x->curlft.packets++;
657                 x->lastused = ktime_get_real_seconds();
658
659                 spin_unlock(&x->lock);
660
661                 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
662
663                 if (xfrm_inner_mode_input(x, skb)) {
664                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
665                         goto drop;
666                 }
667
668                 if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
669                         decaps = 1;
670                         break;
671                 }
672
673                 /*
674                  * We need the inner address.  However, we only get here for
675                  * transport mode so the outer address is identical.
676                  */
677                 daddr = &x->id.daddr;
678                 family = x->props.family;
679
680                 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
681                 if (err < 0) {
682                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
683                         goto drop;
684                 }
685                 crypto_done = false;
686         } while (!err);
687
688         err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
689         if (err)
690                 goto drop;
691
692         nf_reset_ct(skb);
693
694         if (decaps) {
695                 sp = skb_sec_path(skb);
696                 if (sp)
697                         sp->olen = 0;
698                 if (skb_valid_dst(skb))
699                         skb_dst_drop(skb);
700                 gro_cells_receive(&gro_cells, skb);
701                 return 0;
702         } else {
703                 xo = xfrm_offload(skb);
704                 if (xo)
705                         xfrm_gro = xo->flags & XFRM_GRO;
706
707                 err = -EAFNOSUPPORT;
708                 rcu_read_lock();
709                 afinfo = xfrm_state_afinfo_get_rcu(x->props.family);
710                 if (likely(afinfo))
711                         err = afinfo->transport_finish(skb, xfrm_gro || async);
712                 rcu_read_unlock();
713                 if (xfrm_gro) {
714                         sp = skb_sec_path(skb);
715                         if (sp)
716                                 sp->olen = 0;
717                         if (skb_valid_dst(skb))
718                                 skb_dst_drop(skb);
719                         gro_cells_receive(&gro_cells, skb);
720                         return err;
721                 }
722
723                 return err;
724         }
725
726 drop_unlock:
727         spin_unlock(&x->lock);
728 drop:
729         xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
730         kfree_skb(skb);
731         return 0;
732 }
733 EXPORT_SYMBOL(xfrm_input);
734
735 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
736 {
737         return xfrm_input(skb, nexthdr, 0, -1);
738 }
739 EXPORT_SYMBOL(xfrm_input_resume);
740
741 static void xfrm_trans_reinject(struct work_struct *work)
742 {
743         struct xfrm_trans_tasklet *trans = container_of(work, struct xfrm_trans_tasklet, work);
744         struct sk_buff_head queue;
745         struct sk_buff *skb;
746
747         __skb_queue_head_init(&queue);
748         spin_lock_bh(&trans->queue_lock);
749         skb_queue_splice_init(&trans->queue, &queue);
750         spin_unlock_bh(&trans->queue_lock);
751
752         local_bh_disable();
753         while ((skb = __skb_dequeue(&queue)))
754                 XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
755                                                NULL, skb);
756         local_bh_enable();
757 }
758
759 int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
760                          int (*finish)(struct net *, struct sock *,
761                                        struct sk_buff *))
762 {
763         struct xfrm_trans_tasklet *trans;
764
765         trans = this_cpu_ptr(&xfrm_trans_tasklet);
766
767         if (skb_queue_len(&trans->queue) >= READ_ONCE(netdev_max_backlog))
768                 return -ENOBUFS;
769
770         BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
771
772         XFRM_TRANS_SKB_CB(skb)->finish = finish;
773         XFRM_TRANS_SKB_CB(skb)->net = net;
774         spin_lock_bh(&trans->queue_lock);
775         __skb_queue_tail(&trans->queue, skb);
776         spin_unlock_bh(&trans->queue_lock);
777         schedule_work(&trans->work);
778         return 0;
779 }
780 EXPORT_SYMBOL(xfrm_trans_queue_net);
781
782 int xfrm_trans_queue(struct sk_buff *skb,
783                      int (*finish)(struct net *, struct sock *,
784                                    struct sk_buff *))
785 {
786         return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
787 }
788 EXPORT_SYMBOL(xfrm_trans_queue);
789
790 void __init xfrm_input_init(void)
791 {
792         int err;
793         int i;
794
795         init_dummy_netdev(&xfrm_napi_dev);
796         err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
797         if (err)
798                 gro_cells.cells = NULL;
799
800         for_each_possible_cpu(i) {
801                 struct xfrm_trans_tasklet *trans;
802
803                 trans = &per_cpu(xfrm_trans_tasklet, i);
804                 spin_lock_init(&trans->queue_lock);
805                 __skb_queue_head_init(&trans->queue);
806                 INIT_WORK(&trans->work, xfrm_trans_reinject);
807         }
808 }