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 (async && 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 }