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         sp->verified_cnt = 0;
 133
 134         return sp;
 135 }
 136 EXPORT_SYMBOL(secpath_set);
 137
 138 /* Fetch spi and seq from ipsec header */
 139
 140 int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
 141 {
 142         int offset, offset_seq;
 143         int hlen;
 144
 145         switch (nexthdr) {
 146         case IPPROTO_AH:
 147                 hlen = sizeof(struct ip_auth_hdr);
 148                 offset = offsetof(struct ip_auth_hdr, spi);
 149                 offset_seq = offsetof(struct ip_auth_hdr, seq_no);
 150                 break;
 151         case IPPROTO_ESP:
 152                 hlen = sizeof(struct ip_esp_hdr);
 153                 offset = offsetof(struct ip_esp_hdr, spi);
 154                 offset_seq = offsetof(struct ip_esp_hdr, seq_no);
 155                 break;
 156         case IPPROTO_COMP:
 157                 if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
 158                         return -EINVAL;
 159                 *spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2)));
 160                 *seq = 0;
 161                 return 0;
 162         default:
 163                 return 1;
 164         }
 165
 166         if (!pskb_may_pull(skb, hlen))
 167                 return -EINVAL;
 168
 169         *spi = *(__be32 *)(skb_transport_header(skb) + offset);
 170         *seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
 171         return 0;
 172 }
 173 EXPORT_SYMBOL(xfrm_parse_spi);
 174
 175 static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
 176 {
 177         struct iphdr *iph;
 178         int optlen = 0;
 179         int err = -EINVAL;
 180
 181         if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
 182                 struct ip_beet_phdr *ph;
 183                 int phlen;
 184
 185                 if (!pskb_may_pull(skb, sizeof(*ph)))
 186                         goto out;
 187
 188                 ph = (struct ip_beet_phdr *)skb->data;
 189
 190                 phlen = sizeof(*ph) + ph->padlen;
 191                 optlen = ph->hdrlen * 8 + (IPV4_BEET_PHMAXLEN - phlen);
 192                 if (optlen < 0 || optlen & 3 || optlen > 250)
 193                         goto out;
 194
 195                 XFRM_MODE_SKB_CB(skb)->protocol = ph->nexthdr;
 196
 197                 if (!pskb_may_pull(skb, phlen))
 198                         goto out;
 199                 __skb_pull(skb, phlen);
 200         }
 201
 202         skb_push(skb, sizeof(*iph));
 203         skb_reset_network_header(skb);
 204         skb_mac_header_rebuild(skb);
 205
 206         xfrm4_beet_make_header(skb);
 207
 208         iph = ip_hdr(skb);
 209
 210         iph->ihl += optlen / 4;
 211         iph->tot_len = htons(skb->len);
 212         iph->daddr = x->sel.daddr.a4;
 213         iph->saddr = x->sel.saddr.a4;
 214         iph->check = 0;
 215         iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
 216         err = 0;
 217 out:
 218         return err;
 219 }
 220
 221 static void ipip_ecn_decapsulate(struct sk_buff *skb)
 222 {
 223         struct iphdr *inner_iph = ipip_hdr(skb);
 224
 225         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
 226                 IP_ECN_set_ce(inner_iph);
 227 }
 228
 229 static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 230 {
 231         int err = -EINVAL;
 232
 233         if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
 234                 goto out;
 235
 236         if (!pskb_may_pull(skb, sizeof(struct iphdr)))
 237                 goto out;
 238
 239         err = skb_unclone(skb, GFP_ATOMIC);
 240         if (err)
 241                 goto out;
 242
 243         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
 244                 ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
 245         if (!(x->props.flags & XFRM_STATE_NOECN))
 246                 ipip_ecn_decapsulate(skb);
 247
 248         skb_reset_network_header(skb);
 249         skb_mac_header_rebuild(skb);
 250         if (skb->mac_len)
 251                 eth_hdr(skb)->h_proto = skb->protocol;
 252
 253         err = 0;
 254
 255 out:
 256         return err;
 257 }
 258
 259 static void ipip6_ecn_decapsulate(struct sk_buff *skb)
 260 {
 261         struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
 262
 263         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
 264                 IP6_ECN_set_ce(skb, inner_iph);
 265 }
 266
 267 static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 268 {
 269         int err = -EINVAL;
 270
 271         if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
 272                 goto out;
 273         if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
 274                 goto out;
 275
 276         err = skb_unclone(skb, GFP_ATOMIC);
 277         if (err)
 278                 goto out;
 279
 280         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
 281                 ipv6_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipipv6_hdr(skb));
 282         if (!(x->props.flags & XFRM_STATE_NOECN))
 283                 ipip6_ecn_decapsulate(skb);
 284
 285         skb_reset_network_header(skb);
 286         skb_mac_header_rebuild(skb);
 287         if (skb->mac_len)
 288                 eth_hdr(skb)->h_proto = skb->protocol;
 289
 290         err = 0;
 291
 292 out:
 293         return err;
 294 }
 295
 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         struct xfrm_offload *xo = xfrm_offload(skb);
 403         int ihl = skb->data - skb_transport_header(skb);
 404
 405         if (skb->transport_header != skb->network_header) {
 406                 memmove(skb_transport_header(skb),
 407                         skb_network_header(skb), ihl);
 408                 if (xo)
 409                         xo->orig_mac_len =
 410                                 skb_mac_header_was_set(skb) ? skb_mac_header_len(skb) : 0;
 411                 skb->network_header = skb->transport_header;
 412         }
 413         ip_hdr(skb)->tot_len = htons(skb->len + ihl);
 414         skb_reset_transport_header(skb);
 415         return 0;
 416 }
 417
 418 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 419 {
 420 #if IS_ENABLED(CONFIG_IPV6)
 421         struct xfrm_offload *xo = xfrm_offload(skb);
 422         int ihl = skb->data - skb_transport_header(skb);
 423
 424         if (skb->transport_header != skb->network_header) {
 425                 memmove(skb_transport_header(skb),
 426                         skb_network_header(skb), ihl);
 427                 if (xo)
 428                         xo->orig_mac_len =
 429                                 skb_mac_header_was_set(skb) ? skb_mac_header_len(skb) : 0;
 430                 skb->network_header = skb->transport_header;
 431         }
 432         ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
 433                                            sizeof(struct ipv6hdr));
 434         skb_reset_transport_header(skb);
 435         return 0;
 436 #else
 437         WARN_ON_ONCE(1);
 438         return -EAFNOSUPPORT;
 439 #endif
 440 }
 441
 442 static int xfrm_inner_mode_input(struct xfrm_state *x,
 443                                  const struct xfrm_mode *inner_mode,
 444                                  struct sk_buff *skb)
 445 {
 446         switch (inner_mode->encap) {
 447         case XFRM_MODE_BEET:
 448         case XFRM_MODE_TUNNEL:
 449                 return xfrm_prepare_input(x, skb);
 450         case XFRM_MODE_TRANSPORT:
 451                 if (inner_mode->family == AF_INET)
 452                         return xfrm4_transport_input(x, skb);
 453                 if (inner_mode->family == AF_INET6)
 454                         return xfrm6_transport_input(x, skb);
 455                 break;
 456         case XFRM_MODE_ROUTEOPTIMIZATION:
 457                 WARN_ON_ONCE(1);
 458                 break;
 459         default:
 460                 WARN_ON_ONCE(1);
 461                 break;
 462         }
 463
 464         return -EOPNOTSUPP;
 465 }
 466
 467 int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 468 {
 469         const struct xfrm_state_afinfo *afinfo;
 470         struct net *net = dev_net(skb->dev);
 471         const struct xfrm_mode *inner_mode;
 472         int err;
 473         __be32 seq;
 474         __be32 seq_hi;
 475         struct xfrm_state *x = NULL;
 476         xfrm_address_t *daddr;
 477         u32 mark = skb->mark;
 478         unsigned int family = AF_UNSPEC;
 479         int decaps = 0;
 480         int async = 0;
 481         bool xfrm_gro = false;
 482         bool crypto_done = false;
 483         struct xfrm_offload *xo = xfrm_offload(skb);
 484         struct sec_path *sp;
 485
 486         if (encap_type < 0) {
 487                 x = xfrm_input_state(skb);
 488
 489                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
 490                         if (x->km.state == XFRM_STATE_ACQ)
 491                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
 492                         else
 493                                 XFRM_INC_STATS(net,
 494                                                LINUX_MIB_XFRMINSTATEINVALID);
 495
 496                         if (encap_type == -1)
 497                                 dev_put(skb->dev);
 498                         goto drop;
 499                 }
 500
 501                 family = x->outer_mode.family;
 502
 503                 /* An encap_type of -1 indicates async resumption. */
 504                 if (encap_type == -1) {
 505                         async = 1;
 506                         seq = XFRM_SKB_CB(skb)->seq.input.low;
 507                         goto resume;
 508                 }
 509
 510                 /* encap_type < -1 indicates a GRO call. */
 511                 encap_type = 0;
 512                 seq = XFRM_SPI_SKB_CB(skb)->seq;
 513
 514                 if (xo && (xo->flags & CRYPTO_DONE)) {
 515                         crypto_done = true;
 516                         family = XFRM_SPI_SKB_CB(skb)->family;
 517
 518                         if (!(xo->status & CRYPTO_SUCCESS)) {
 519                                 if (xo->status &
 520                                     (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
 521                                      CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
 522                                      CRYPTO_TUNNEL_AH_AUTH_FAILED |
 523                                      CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
 524
 525                                         xfrm_audit_state_icvfail(x, skb,
 526                                                                  x->type->proto);
 527                                         x->stats.integrity_failed++;
 528                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 529                                         goto drop;
 530                                 }
 531
 532                                 if (xo->status & CRYPTO_INVALID_PROTOCOL) {
 533                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 534                                         goto drop;
 535                                 }
 536
 537                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 538                                 goto drop;
 539                         }
 540
 541                         if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
 542                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 543                                 goto drop;
 544                         }
 545                 }
 546
 547                 goto lock;
 548         }
 549
 550         family = XFRM_SPI_SKB_CB(skb)->family;
 551
 552         /* if tunnel is present override skb->mark value with tunnel i_key */
 553         switch (family) {
 554         case AF_INET:
 555                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
 556                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
 557                 break;
 558         case AF_INET6:
 559                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
 560                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
 561                 break;
 562         }
 563
 564         sp = secpath_set(skb);
 565         if (!sp) {
 566                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
 567                 goto drop;
 568         }
 569
 570         seq = 0;
 571         if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
 572                 secpath_reset(skb);
 573                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 574                 goto drop;
 575         }
 576
 577         daddr = (xfrm_address_t *)(skb_network_header(skb) +
 578                                    XFRM_SPI_SKB_CB(skb)->daddroff);
 579         do {
 580                 sp = skb_sec_path(skb);
 581
 582                 if (sp->len == XFRM_MAX_DEPTH) {
 583                         secpath_reset(skb);
 584                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 585                         goto drop;
 586                 }
 587
 588                 x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
 589                 if (x == NULL) {
 590                         secpath_reset(skb);
 591                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
 592                         xfrm_audit_state_notfound(skb, family, spi, seq);
 593                         goto drop;
 594                 }
 595
 596                 skb->mark = xfrm_smark_get(skb->mark, x);
 597
 598                 sp->xvec[sp->len++] = x;
 599
 600                 skb_dst_force(skb);
 601                 if (!skb_dst(skb)) {
 602                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
 603                         goto drop;
 604                 }
 605
 606 lock:
 607                 spin_lock(&x->lock);
 608
 609                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
 610                         if (x->km.state == XFRM_STATE_ACQ)
 611                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
 612                         else
 613                                 XFRM_INC_STATS(net,
 614                                                LINUX_MIB_XFRMINSTATEINVALID);
 615                         goto drop_unlock;
 616                 }
 617
 618                 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
 619                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
 620                         goto drop_unlock;
 621                 }
 622
 623                 if (x->repl->check(x, skb, seq)) {
 624                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 625                         goto drop_unlock;
 626                 }
 627
 628                 if (xfrm_state_check_expire(x)) {
 629                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
 630                         goto drop_unlock;
 631                 }
 632
 633                 spin_unlock(&x->lock);
 634
 635                 if (xfrm_tunnel_check(skb, x, family)) {
 636                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 637                         goto drop;
 638                 }
 639
 640                 seq_hi = htonl(xfrm_replay_seqhi(x, seq));
 641
 642                 XFRM_SKB_CB(skb)->seq.input.low = seq;
 643                 XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
 644
 645                 dev_hold(skb->dev);
 646
 647                 if (crypto_done)
 648                         nexthdr = x->type_offload->input_tail(x, skb);
 649                 else
 650                         nexthdr = x->type->input(x, skb);
 651
 652                 if (nexthdr == -EINPROGRESS)
 653                         return 0;
 654 resume:
 655                 dev_put(skb->dev);
 656
 657                 spin_lock(&x->lock);
 658                 if (nexthdr < 0) {
 659                         if (nexthdr == -EBADMSG) {
 660                                 xfrm_audit_state_icvfail(x, skb,
 661                                                          x->type->proto);
 662                                 x->stats.integrity_failed++;
 663                         }
 664                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 665                         goto drop_unlock;
 666                 }
 667
 668                 /* only the first xfrm gets the encap type */
 669                 encap_type = 0;
 670
 671                 if (x->repl->recheck(x, skb, seq)) {
 672                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 673                         goto drop_unlock;
 674                 }
 675
 676                 x->repl->advance(x, seq);
 677
 678                 x->curlft.bytes += skb->len;
 679                 x->curlft.packets++;
 680
 681                 spin_unlock(&x->lock);
 682
 683                 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
 684
 685                 inner_mode = &x->inner_mode;
 686
 687                 if (x->sel.family == AF_UNSPEC) {
 688                         inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
 689                         if (inner_mode == NULL) {
 690                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 691                                 goto drop;
 692                         }
 693                 }
 694
 695                 if (xfrm_inner_mode_input(x, inner_mode, skb)) {
 696                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 697                         goto drop;
 698                 }
 699
 700                 if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
 701                         decaps = 1;
 702                         break;
 703                 }
 704
 705                 /*
 706                  * We need the inner address.  However, we only get here for
 707                  * transport mode so the outer address is identical.
 708                  */
 709                 daddr = &x->id.daddr;
 710                 family = x->outer_mode.family;
 711
 712                 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
 713                 if (err < 0) {
 714                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 715                         goto drop;
 716                 }
 717                 crypto_done = false;
 718         } while (!err);
 719
 720         err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
 721         if (err)
 722                 goto drop;
 723
 724         nf_reset_ct(skb);
 725
 726         if (decaps) {
 727                 sp = skb_sec_path(skb);
 728                 if (sp)
 729                         sp->olen = 0;
 730                 skb_dst_drop(skb);
 731                 gro_cells_receive(&gro_cells, skb);
 732                 return 0;
 733         } else {
 734                 xo = xfrm_offload(skb);
 735                 if (xo)
 736                         xfrm_gro = xo->flags & XFRM_GRO;
 737
 738                 err = -EAFNOSUPPORT;
 739                 rcu_read_lock();
 740                 afinfo = xfrm_state_afinfo_get_rcu(x->inner_mode.family);
 741                 if (likely(afinfo))
 742                         err = afinfo->transport_finish(skb, xfrm_gro || async);
 743                 rcu_read_unlock();
 744                 if (xfrm_gro) {
 745                         sp = skb_sec_path(skb);
 746                         if (sp)
 747                                 sp->olen = 0;
 748                         skb_dst_drop(skb);
 749                         gro_cells_receive(&gro_cells, skb);
 750                         return err;
 751                 }
 752
 753                 return err;
 754         }
 755
 756 drop_unlock:
 757         spin_unlock(&x->lock);
 758 drop:
 759         xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
 760         kfree_skb(skb);
 761         return 0;
 762 }
 763 EXPORT_SYMBOL(xfrm_input);
 764
 765 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
 766 {
 767         return xfrm_input(skb, nexthdr, 0, -1);
 768 }
 769 EXPORT_SYMBOL(xfrm_input_resume);
 770
 771 static void xfrm_trans_reinject(unsigned long data)
 772 {
 773         struct xfrm_trans_tasklet *trans = (void *)data;
 774         struct sk_buff_head queue;
 775         struct sk_buff *skb;
 776
 777         __skb_queue_head_init(&queue);
 778         skb_queue_splice_init(&trans->queue, &queue);
 779
 780         while ((skb = __skb_dequeue(&queue)))
 781                 XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
 782                                                NULL, skb);
 783 }
 784
 785 int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
 786                          int (*finish)(struct net *, struct sock *,
 787                                        struct sk_buff *))
 788 {
 789         struct xfrm_trans_tasklet *trans;
 790
 791         trans = this_cpu_ptr(&xfrm_trans_tasklet);
 792
 793         if (skb_queue_len(&trans->queue) >= READ_ONCE(netdev_max_backlog))
 794                 return -ENOBUFS;
 795
 796         BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
 797
 798         XFRM_TRANS_SKB_CB(skb)->finish = finish;
 799         XFRM_TRANS_SKB_CB(skb)->net = net;
 800         __skb_queue_tail(&trans->queue, skb);
 801         tasklet_schedule(&trans->tasklet);
 802         return 0;
 803 }
 804 EXPORT_SYMBOL(xfrm_trans_queue_net);
 805
 806 int xfrm_trans_queue(struct sk_buff *skb,
 807                      int (*finish)(struct net *, struct sock *,
 808                                    struct sk_buff *))
 809 {
 810         return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
 811 }
 812 EXPORT_SYMBOL(xfrm_trans_queue);
 813
 814 void __init xfrm_input_init(void)
 815 {
 816         int err;
 817         int i;
 818
 819         init_dummy_netdev(&xfrm_napi_dev);
 820         err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
 821         if (err)
 822                 gro_cells.cells = NULL;
 823
 824         for_each_possible_cpu(i) {
 825                 struct xfrm_trans_tasklet *trans;
 826
 827                 trans = &per_cpu(xfrm_trans_tasklet, i);
 828                 __skb_queue_head_init(&trans->queue);
 829                 tasklet_init(&trans->tasklet, xfrm_trans_reinject,
 830                              (unsigned long)trans);
 831         }
 832 }