Merge tag 'spi-fix-v5.13-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brooni...
[linux-2.6-microblaze.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
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
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
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
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
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
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
133         return sp;
134 }
135 EXPORT_SYMBOL(secpath_set);
136
137 /* Fetch spi and seq from ipsec header */
138
139 int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
140 {
141         int offset, offset_seq;
142         int hlen;
143
144         switch (nexthdr) {
145         case IPPROTO_AH:
146                 hlen = sizeof(struct ip_auth_hdr);
147                 offset = offsetof(struct ip_auth_hdr, spi);
148                 offset_seq = offsetof(struct ip_auth_hdr, seq_no);
149                 break;
150         case IPPROTO_ESP:
151                 hlen = sizeof(struct ip_esp_hdr);
152                 offset = offsetof(struct ip_esp_hdr, spi);
153                 offset_seq = offsetof(struct ip_esp_hdr, seq_no);
154                 break;
155         case IPPROTO_COMP:
156                 if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
157                         return -EINVAL;
158                 *spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2)));
159                 *seq = 0;
160                 return 0;
161         default:
162                 return 1;
163         }
164
165         if (!pskb_may_pull(skb, hlen))
166                 return -EINVAL;
167
168         *spi = *(__be32 *)(skb_transport_header(skb) + offset);
169         *seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
170         return 0;
171 }
172 EXPORT_SYMBOL(xfrm_parse_spi);
173
174 static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
175 {
176         struct iphdr *iph;
177         int optlen = 0;
178         int err = -EINVAL;
179
180         if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
181                 struct ip_beet_phdr *ph;
182                 int phlen;
183
184                 if (!pskb_may_pull(skb, sizeof(*ph)))
185                         goto out;
186
187                 ph = (struct ip_beet_phdr *)skb->data;
188
189                 phlen = sizeof(*ph) + ph->padlen;
190                 optlen = ph->hdrlen * 8 + (IPV4_BEET_PHMAXLEN - phlen);
191                 if (optlen < 0 || optlen & 3 || optlen > 250)
192                         goto out;
193
194                 XFRM_MODE_SKB_CB(skb)->protocol = ph->nexthdr;
195
196                 if (!pskb_may_pull(skb, phlen))
197                         goto out;
198                 __skb_pull(skb, phlen);
199         }
200
201         skb_push(skb, sizeof(*iph));
202         skb_reset_network_header(skb);
203         skb_mac_header_rebuild(skb);
204
205         xfrm4_beet_make_header(skb);
206
207         iph = ip_hdr(skb);
208
209         iph->ihl += optlen / 4;
210         iph->tot_len = htons(skb->len);
211         iph->daddr = x->sel.daddr.a4;
212         iph->saddr = x->sel.saddr.a4;
213         iph->check = 0;
214         iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
215         err = 0;
216 out:
217         return err;
218 }
219
220 static void ipip_ecn_decapsulate(struct sk_buff *skb)
221 {
222         struct iphdr *inner_iph = ipip_hdr(skb);
223
224         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
225                 IP_ECN_set_ce(inner_iph);
226 }
227
228 static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
229 {
230         int err = -EINVAL;
231
232         if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
233                 goto out;
234
235         if (!pskb_may_pull(skb, sizeof(struct iphdr)))
236                 goto out;
237
238         err = skb_unclone(skb, GFP_ATOMIC);
239         if (err)
240                 goto out;
241
242         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
243                 ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
244         if (!(x->props.flags & XFRM_STATE_NOECN))
245                 ipip_ecn_decapsulate(skb);
246
247         skb_reset_network_header(skb);
248         skb_mac_header_rebuild(skb);
249         if (skb->mac_len)
250                 eth_hdr(skb)->h_proto = skb->protocol;
251
252         err = 0;
253
254 out:
255         return err;
256 }
257
258 static void ipip6_ecn_decapsulate(struct sk_buff *skb)
259 {
260         struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
261
262         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
263                 IP6_ECN_set_ce(skb, inner_iph);
264 }
265
266 static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
267 {
268         int err = -EINVAL;
269
270         if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
271                 goto out;
272         if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
273                 goto out;
274
275         err = skb_unclone(skb, GFP_ATOMIC);
276         if (err)
277                 goto out;
278
279         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
280                 ipv6_copy_dscp(ipv6_get_dsfield(ipv6_hdr(skb)),
281                                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
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
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
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  */
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
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
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
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                 skb->mark = xfrm_smark_get(skb->mark, x);
589
590                 sp->xvec[sp->len++] = x;
591
592                 skb_dst_force(skb);
593                 if (!skb_dst(skb)) {
594                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
595                         goto drop;
596                 }
597
598 lock:
599                 spin_lock(&x->lock);
600
601                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
602                         if (x->km.state == XFRM_STATE_ACQ)
603                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
604                         else
605                                 XFRM_INC_STATS(net,
606                                                LINUX_MIB_XFRMINSTATEINVALID);
607                         goto drop_unlock;
608                 }
609
610                 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
611                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
612                         goto drop_unlock;
613                 }
614
615                 if (x->repl->check(x, skb, seq)) {
616                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
617                         goto drop_unlock;
618                 }
619
620                 if (xfrm_state_check_expire(x)) {
621                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
622                         goto drop_unlock;
623                 }
624
625                 spin_unlock(&x->lock);
626
627                 if (xfrm_tunnel_check(skb, x, family)) {
628                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
629                         goto drop;
630                 }
631
632                 seq_hi = htonl(xfrm_replay_seqhi(x, seq));
633
634                 XFRM_SKB_CB(skb)->seq.input.low = seq;
635                 XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
636
637                 dev_hold(skb->dev);
638
639                 if (crypto_done)
640                         nexthdr = x->type_offload->input_tail(x, skb);
641                 else
642                         nexthdr = x->type->input(x, skb);
643
644                 if (nexthdr == -EINPROGRESS)
645                         return 0;
646 resume:
647                 dev_put(skb->dev);
648
649                 spin_lock(&x->lock);
650                 if (nexthdr < 0) {
651                         if (nexthdr == -EBADMSG) {
652                                 xfrm_audit_state_icvfail(x, skb,
653                                                          x->type->proto);
654                                 x->stats.integrity_failed++;
655                         }
656                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
657                         goto drop_unlock;
658                 }
659
660                 /* only the first xfrm gets the encap type */
661                 encap_type = 0;
662
663                 if (x->repl->recheck(x, skb, seq)) {
664                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
665                         goto drop_unlock;
666                 }
667
668                 x->repl->advance(x, seq);
669
670                 x->curlft.bytes += skb->len;
671                 x->curlft.packets++;
672
673                 spin_unlock(&x->lock);
674
675                 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
676
677                 inner_mode = &x->inner_mode;
678
679                 if (x->sel.family == AF_UNSPEC) {
680                         inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
681                         if (inner_mode == NULL) {
682                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
683                                 goto drop;
684                         }
685                 }
686
687                 if (xfrm_inner_mode_input(x, inner_mode, skb)) {
688                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
689                         goto drop;
690                 }
691
692                 if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
693                         decaps = 1;
694                         break;
695                 }
696
697                 /*
698                  * We need the inner address.  However, we only get here for
699                  * transport mode so the outer address is identical.
700                  */
701                 daddr = &x->id.daddr;
702                 family = x->outer_mode.family;
703
704                 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
705                 if (err < 0) {
706                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
707                         goto drop;
708                 }
709                 crypto_done = false;
710         } while (!err);
711
712         err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
713         if (err)
714                 goto drop;
715
716         nf_reset_ct(skb);
717
718         if (decaps) {
719                 sp = skb_sec_path(skb);
720                 if (sp)
721                         sp->olen = 0;
722                 skb_dst_drop(skb);
723                 gro_cells_receive(&gro_cells, skb);
724                 return 0;
725         } else {
726                 xo = xfrm_offload(skb);
727                 if (xo)
728                         xfrm_gro = xo->flags & XFRM_GRO;
729
730                 err = -EAFNOSUPPORT;
731                 rcu_read_lock();
732                 afinfo = xfrm_state_afinfo_get_rcu(x->inner_mode.family);
733                 if (likely(afinfo))
734                         err = afinfo->transport_finish(skb, xfrm_gro || async);
735                 rcu_read_unlock();
736                 if (xfrm_gro) {
737                         sp = skb_sec_path(skb);
738                         if (sp)
739                                 sp->olen = 0;
740                         skb_dst_drop(skb);
741                         gro_cells_receive(&gro_cells, skb);
742                         return err;
743                 }
744
745                 return err;
746         }
747
748 drop_unlock:
749         spin_unlock(&x->lock);
750 drop:
751         xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
752         kfree_skb(skb);
753         return 0;
754 }
755 EXPORT_SYMBOL(xfrm_input);
756
757 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
758 {
759         return xfrm_input(skb, nexthdr, 0, -1);
760 }
761 EXPORT_SYMBOL(xfrm_input_resume);
762
763 static void xfrm_trans_reinject(struct tasklet_struct *t)
764 {
765         struct xfrm_trans_tasklet *trans = from_tasklet(trans, t, tasklet);
766         struct sk_buff_head queue;
767         struct sk_buff *skb;
768
769         __skb_queue_head_init(&queue);
770         skb_queue_splice_init(&trans->queue, &queue);
771
772         while ((skb = __skb_dequeue(&queue)))
773                 XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
774                                                NULL, skb);
775 }
776
777 int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
778                          int (*finish)(struct net *, struct sock *,
779                                        struct sk_buff *))
780 {
781         struct xfrm_trans_tasklet *trans;
782
783         trans = this_cpu_ptr(&xfrm_trans_tasklet);
784
785         if (skb_queue_len(&trans->queue) >= netdev_max_backlog)
786                 return -ENOBUFS;
787
788         BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
789
790         XFRM_TRANS_SKB_CB(skb)->finish = finish;
791         XFRM_TRANS_SKB_CB(skb)->net = net;
792         __skb_queue_tail(&trans->queue, skb);
793         tasklet_schedule(&trans->tasklet);
794         return 0;
795 }
796 EXPORT_SYMBOL(xfrm_trans_queue_net);
797
798 int xfrm_trans_queue(struct sk_buff *skb,
799                      int (*finish)(struct net *, struct sock *,
800                                    struct sk_buff *))
801 {
802         return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
803 }
804 EXPORT_SYMBOL(xfrm_trans_queue);
805
806 void __init xfrm_input_init(void)
807 {
808         int err;
809         int i;
810
811         init_dummy_netdev(&xfrm_napi_dev);
812         err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
813         if (err)
814                 gro_cells.cells = NULL;
815
816         for_each_possible_cpu(i) {
817                 struct xfrm_trans_tasklet *trans;
818
819                 trans = &per_cpu(xfrm_trans_tasklet, i);
820                 __skb_queue_head_init(&trans->queue);
821                 tasklet_setup(&trans->tasklet, xfrm_trans_reinject);
822         }
823 }