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 #include <net/hotdata.h>
  25
  26 #include "xfrm_inout.h"
  27
  28 struct xfrm_trans_tasklet {
  29         struct work_struct work;
  30         spinlock_t queue_lock;
  31         struct sk_buff_head queue;
  32 };
  33
  34 struct xfrm_trans_cb {
  35         union {
  36                 struct inet_skb_parm    h4;
  37 #if IS_ENABLED(CONFIG_IPV6)
  38                 struct inet6_skb_parm   h6;
  39 #endif
  40         } header;
  41         int (*finish)(struct net *net, struct sock *sk, struct sk_buff *skb);
  42         struct net *net;
  43 };
  44
  45 #define XFRM_TRANS_SKB_CB(__skb) ((struct xfrm_trans_cb *)&((__skb)->cb[0]))
  46
  47 static DEFINE_SPINLOCK(xfrm_input_afinfo_lock);
  48 static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[2][AF_INET6 + 1];
  49
  50 static struct gro_cells gro_cells;
  51 static struct net_device xfrm_napi_dev;
  52
  53 static DEFINE_PER_CPU(struct xfrm_trans_tasklet, xfrm_trans_tasklet);
  54
  55 int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo)
  56 {
  57         int err = 0;
  58
  59         if (WARN_ON(afinfo->family > AF_INET6))
  60                 return -EAFNOSUPPORT;
  61
  62         spin_lock_bh(&xfrm_input_afinfo_lock);
  63         if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family]))
  64                 err = -EEXIST;
  65         else
  66                 rcu_assign_pointer(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], afinfo);
  67         spin_unlock_bh(&xfrm_input_afinfo_lock);
  68         return err;
  69 }
  70 EXPORT_SYMBOL(xfrm_input_register_afinfo);
  71
  72 int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo)
  73 {
  74         int err = 0;
  75
  76         spin_lock_bh(&xfrm_input_afinfo_lock);
  77         if (likely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family])) {
  78                 if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family] != afinfo))
  79                         err = -EINVAL;
  80                 else
  81                         RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], NULL);
  82         }
  83         spin_unlock_bh(&xfrm_input_afinfo_lock);
  84         synchronize_rcu();
  85         return err;
  86 }
  87 EXPORT_SYMBOL(xfrm_input_unregister_afinfo);
  88
  89 static const struct xfrm_input_afinfo *xfrm_input_get_afinfo(u8 family, bool is_ipip)
  90 {
  91         const struct xfrm_input_afinfo *afinfo;
  92
  93         if (WARN_ON_ONCE(family > AF_INET6))
  94                 return NULL;
  95
  96         rcu_read_lock();
  97         afinfo = rcu_dereference(xfrm_input_afinfo[is_ipip][family]);
  98         if (unlikely(!afinfo))
  99                 rcu_read_unlock();
 100         return afinfo;
 101 }
 102
 103 static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
 104                        int err)
 105 {
 106         bool is_ipip = (protocol == IPPROTO_IPIP || protocol == IPPROTO_IPV6);
 107         const struct xfrm_input_afinfo *afinfo;
 108         int ret;
 109
 110         afinfo = xfrm_input_get_afinfo(family, is_ipip);
 111         if (!afinfo)
 112                 return -EAFNOSUPPORT;
 113
 114         ret = afinfo->callback(skb, protocol, err);
 115         rcu_read_unlock();
 116
 117         return ret;
 118 }
 119
 120 struct sec_path *secpath_set(struct sk_buff *skb)
 121 {
 122         struct sec_path *sp, *tmp = skb_ext_find(skb, SKB_EXT_SEC_PATH);
 123
 124         sp = skb_ext_add(skb, SKB_EXT_SEC_PATH);
 125         if (!sp)
 126                 return NULL;
 127
 128         if (tmp) /* reused existing one (was COW'd if needed) */
 129                 return sp;
 130
 131         /* allocated new secpath */
 132         memset(sp->ovec, 0, sizeof(sp->ovec));
 133         sp->olen = 0;
 134         sp->len = 0;
 135         sp->verified_cnt = 0;
 136
 137         return sp;
 138 }
 139 EXPORT_SYMBOL(secpath_set);
 140
 141 /* Fetch spi and seq from ipsec header */
 142
 143 int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
 144 {
 145         int offset, offset_seq;
 146         int hlen;
 147
 148         switch (nexthdr) {
 149         case IPPROTO_AH:
 150                 hlen = sizeof(struct ip_auth_hdr);
 151                 offset = offsetof(struct ip_auth_hdr, spi);
 152                 offset_seq = offsetof(struct ip_auth_hdr, seq_no);
 153                 break;
 154         case IPPROTO_ESP:
 155                 hlen = sizeof(struct ip_esp_hdr);
 156                 offset = offsetof(struct ip_esp_hdr, spi);
 157                 offset_seq = offsetof(struct ip_esp_hdr, seq_no);
 158                 break;
 159         case IPPROTO_COMP:
 160                 if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
 161                         return -EINVAL;
 162                 *spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2)));
 163                 *seq = 0;
 164                 return 0;
 165         default:
 166                 return 1;
 167         }
 168
 169         if (!pskb_may_pull(skb, hlen))
 170                 return -EINVAL;
 171
 172         *spi = *(__be32 *)(skb_transport_header(skb) + offset);
 173         *seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
 174         return 0;
 175 }
 176 EXPORT_SYMBOL(xfrm_parse_spi);
 177
 178 static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
 179 {
 180         struct iphdr *iph;
 181         int optlen = 0;
 182         int err = -EINVAL;
 183
 184         skb->protocol = htons(ETH_P_IP);
 185
 186         if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
 187                 struct ip_beet_phdr *ph;
 188                 int phlen;
 189
 190                 if (!pskb_may_pull(skb, sizeof(*ph)))
 191                         goto out;
 192
 193                 ph = (struct ip_beet_phdr *)skb->data;
 194
 195                 phlen = sizeof(*ph) + ph->padlen;
 196                 optlen = ph->hdrlen * 8 + (IPV4_BEET_PHMAXLEN - phlen);
 197                 if (optlen < 0 || optlen & 3 || optlen > 250)
 198                         goto out;
 199
 200                 XFRM_MODE_SKB_CB(skb)->protocol = ph->nexthdr;
 201
 202                 if (!pskb_may_pull(skb, phlen))
 203                         goto out;
 204                 __skb_pull(skb, phlen);
 205         }
 206
 207         skb_push(skb, sizeof(*iph));
 208         skb_reset_network_header(skb);
 209         skb_mac_header_rebuild(skb);
 210
 211         xfrm4_beet_make_header(skb);
 212
 213         iph = ip_hdr(skb);
 214
 215         iph->ihl += optlen / 4;
 216         iph->tot_len = htons(skb->len);
 217         iph->daddr = x->sel.daddr.a4;
 218         iph->saddr = x->sel.saddr.a4;
 219         iph->check = 0;
 220         iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
 221         err = 0;
 222 out:
 223         return err;
 224 }
 225
 226 static void ipip_ecn_decapsulate(struct sk_buff *skb)
 227 {
 228         struct iphdr *inner_iph = ipip_hdr(skb);
 229
 230         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
 231                 IP_ECN_set_ce(inner_iph);
 232 }
 233
 234 static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 235 {
 236         int err = -EINVAL;
 237
 238         skb->protocol = htons(ETH_P_IP);
 239
 240         if (!pskb_may_pull(skb, sizeof(struct iphdr)))
 241                 goto out;
 242
 243         err = skb_unclone(skb, GFP_ATOMIC);
 244         if (err)
 245                 goto out;
 246
 247         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
 248                 ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
 249         if (!(x->props.flags & XFRM_STATE_NOECN))
 250                 ipip_ecn_decapsulate(skb);
 251
 252         skb_reset_network_header(skb);
 253         skb_mac_header_rebuild(skb);
 254         if (skb->mac_len)
 255                 eth_hdr(skb)->h_proto = skb->protocol;
 256
 257         err = 0;
 258
 259 out:
 260         return err;
 261 }
 262
 263 static void ipip6_ecn_decapsulate(struct sk_buff *skb)
 264 {
 265         struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
 266
 267         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
 268                 IP6_ECN_set_ce(skb, inner_iph);
 269 }
 270
 271 static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 272 {
 273         int err = -EINVAL;
 274
 275         skb->protocol = htons(ETH_P_IPV6);
 276
 277         if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
 278                 goto out;
 279
 280         err = skb_unclone(skb, GFP_ATOMIC);
 281         if (err)
 282                 goto out;
 283
 284         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
 285                 ipv6_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipipv6_hdr(skb));
 286         if (!(x->props.flags & XFRM_STATE_NOECN))
 287                 ipip6_ecn_decapsulate(skb);
 288
 289         skb_reset_network_header(skb);
 290         skb_mac_header_rebuild(skb);
 291         if (skb->mac_len)
 292                 eth_hdr(skb)->h_proto = skb->protocol;
 293
 294         err = 0;
 295
 296 out:
 297         return err;
 298 }
 299
 300 static int xfrm6_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
 301 {
 302         struct ipv6hdr *ip6h;
 303         int size = sizeof(struct ipv6hdr);
 304         int err;
 305
 306         skb->protocol = htons(ETH_P_IPV6);
 307
 308         err = skb_cow_head(skb, size + skb->mac_len);
 309         if (err)
 310                 goto out;
 311
 312         __skb_push(skb, size);
 313         skb_reset_network_header(skb);
 314         skb_mac_header_rebuild(skb);
 315
 316         xfrm6_beet_make_header(skb);
 317
 318         ip6h = ipv6_hdr(skb);
 319         ip6h->payload_len = htons(skb->len - size);
 320         ip6h->daddr = x->sel.daddr.in6;
 321         ip6h->saddr = x->sel.saddr.in6;
 322         err = 0;
 323 out:
 324         return err;
 325 }
 326
 327 /* Remove encapsulation header.
 328  *
 329  * The IP header will be moved over the top of the encapsulation
 330  * header.
 331  *
 332  * On entry, the transport header shall point to where the IP header
 333  * should be and the network header shall be set to where the IP
 334  * header currently is.  skb->data shall point to the start of the
 335  * payload.
 336  */
 337 static int
 338 xfrm_inner_mode_encap_remove(struct xfrm_state *x,
 339                              struct sk_buff *skb)
 340 {
 341         switch (x->props.mode) {
 342         case XFRM_MODE_BEET:
 343                 switch (x->sel.family) {
 344                 case AF_INET:
 345                         return xfrm4_remove_beet_encap(x, skb);
 346                 case AF_INET6:
 347                         return xfrm6_remove_beet_encap(x, skb);
 348                 }
 349                 break;
 350         case XFRM_MODE_TUNNEL:
 351                 switch (XFRM_MODE_SKB_CB(skb)->protocol) {
 352                 case IPPROTO_IPIP:
 353                         return xfrm4_remove_tunnel_encap(x, skb);
 354                 case IPPROTO_IPV6:
 355                         return xfrm6_remove_tunnel_encap(x, skb);
 356                 break;
 357                 }
 358                 return -EINVAL;
 359         }
 360
 361         WARN_ON_ONCE(1);
 362         return -EOPNOTSUPP;
 363 }
 364
 365 static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 366 {
 367         switch (x->props.family) {
 368         case AF_INET:
 369                 xfrm4_extract_header(skb);
 370                 break;
 371         case AF_INET6:
 372                 xfrm6_extract_header(skb);
 373                 break;
 374         default:
 375                 WARN_ON_ONCE(1);
 376                 return -EAFNOSUPPORT;
 377         }
 378
 379         return xfrm_inner_mode_encap_remove(x, skb);
 380 }
 381
 382 /* Remove encapsulation header.
 383  *
 384  * The IP header will be moved over the top of the encapsulation header.
 385  *
 386  * On entry, skb_transport_header() shall point to where the IP header
 387  * should be and skb_network_header() shall be set to where the IP header
 388  * currently is.  skb->data shall point to the start of the payload.
 389  */
 390 static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 391 {
 392         struct xfrm_offload *xo = xfrm_offload(skb);
 393         int ihl = skb->data - skb_transport_header(skb);
 394
 395         if (skb->transport_header != skb->network_header) {
 396                 memmove(skb_transport_header(skb),
 397                         skb_network_header(skb), ihl);
 398                 if (xo)
 399                         xo->orig_mac_len =
 400                                 skb_mac_header_was_set(skb) ? skb_mac_header_len(skb) : 0;
 401                 skb->network_header = skb->transport_header;
 402         }
 403         ip_hdr(skb)->tot_len = htons(skb->len + ihl);
 404         skb_reset_transport_header(skb);
 405         return 0;
 406 }
 407
 408 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 409 {
 410 #if IS_ENABLED(CONFIG_IPV6)
 411         struct xfrm_offload *xo = xfrm_offload(skb);
 412         int ihl = skb->data - skb_transport_header(skb);
 413
 414         if (skb->transport_header != skb->network_header) {
 415                 memmove(skb_transport_header(skb),
 416                         skb_network_header(skb), ihl);
 417                 if (xo)
 418                         xo->orig_mac_len =
 419                                 skb_mac_header_was_set(skb) ? skb_mac_header_len(skb) : 0;
 420                 skb->network_header = skb->transport_header;
 421         }
 422         ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
 423                                            sizeof(struct ipv6hdr));
 424         skb_reset_transport_header(skb);
 425         return 0;
 426 #else
 427         WARN_ON_ONCE(1);
 428         return -EAFNOSUPPORT;
 429 #endif
 430 }
 431
 432 static int xfrm_inner_mode_input(struct xfrm_state *x,
 433                                  struct sk_buff *skb)
 434 {
 435         switch (x->props.mode) {
 436         case XFRM_MODE_BEET:
 437         case XFRM_MODE_TUNNEL:
 438                 return xfrm_prepare_input(x, skb);
 439         case XFRM_MODE_TRANSPORT:
 440                 if (x->props.family == AF_INET)
 441                         return xfrm4_transport_input(x, skb);
 442                 if (x->props.family == AF_INET6)
 443                         return xfrm6_transport_input(x, skb);
 444                 break;
 445         case XFRM_MODE_ROUTEOPTIMIZATION:
 446                 WARN_ON_ONCE(1);
 447                 break;
 448         default:
 449                 WARN_ON_ONCE(1);
 450                 break;
 451         }
 452
 453         return -EOPNOTSUPP;
 454 }
 455
 456 int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 457 {
 458         const struct xfrm_state_afinfo *afinfo;
 459         struct net *net = dev_net(skb->dev);
 460         int err;
 461         __be32 seq;
 462         __be32 seq_hi;
 463         struct xfrm_state *x = NULL;
 464         xfrm_address_t *daddr;
 465         u32 mark = skb->mark;
 466         unsigned int family = AF_UNSPEC;
 467         int decaps = 0;
 468         int async = 0;
 469         bool xfrm_gro = false;
 470         bool crypto_done = false;
 471         struct xfrm_offload *xo = xfrm_offload(skb);
 472         struct sec_path *sp;
 473
 474         if (encap_type < 0 || (xo && xo->flags & XFRM_GRO)) {
 475                 x = xfrm_input_state(skb);
 476
 477                 if (unlikely(x->dir && x->dir != XFRM_SA_DIR_IN)) {
 478                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEDIRERROR);
 479                         goto drop;
 480                 }
 481
 482                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
 483                         if (x->km.state == XFRM_STATE_ACQ)
 484                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
 485                         else
 486                                 XFRM_INC_STATS(net,
 487                                                LINUX_MIB_XFRMINSTATEINVALID);
 488
 489                         if (encap_type == -1)
 490                                 dev_put(skb->dev);
 491                         goto drop;
 492                 }
 493
 494                 family = x->props.family;
 495
 496                 /* An encap_type of -1 indicates async resumption. */
 497                 if (encap_type == -1) {
 498                         async = 1;
 499                         seq = XFRM_SKB_CB(skb)->seq.input.low;
 500                         goto resume;
 501                 }
 502                 /* GRO call */
 503                 seq = XFRM_SPI_SKB_CB(skb)->seq;
 504
 505                 if (xo && (xo->flags & CRYPTO_DONE)) {
 506                         crypto_done = true;
 507                         family = XFRM_SPI_SKB_CB(skb)->family;
 508
 509                         if (!(xo->status & CRYPTO_SUCCESS)) {
 510                                 if (xo->status &
 511                                     (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
 512                                      CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
 513                                      CRYPTO_TUNNEL_AH_AUTH_FAILED |
 514                                      CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
 515
 516                                         xfrm_audit_state_icvfail(x, skb,
 517                                                                  x->type->proto);
 518                                         x->stats.integrity_failed++;
 519                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 520                                         goto drop;
 521                                 }
 522
 523                                 if (xo->status & CRYPTO_INVALID_PROTOCOL) {
 524                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 525                                         goto drop;
 526                                 }
 527
 528                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 529                                 goto drop;
 530                         }
 531
 532                         if (xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
 533                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 534                                 goto drop;
 535                         }
 536                 }
 537
 538                 goto lock;
 539         }
 540
 541         family = XFRM_SPI_SKB_CB(skb)->family;
 542
 543         /* if tunnel is present override skb->mark value with tunnel i_key */
 544         switch (family) {
 545         case AF_INET:
 546                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
 547                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
 548                 break;
 549         case AF_INET6:
 550                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
 551                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
 552                 break;
 553         }
 554
 555         sp = secpath_set(skb);
 556         if (!sp) {
 557                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
 558                 goto drop;
 559         }
 560
 561         seq = 0;
 562         if (!spi && xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
 563                 secpath_reset(skb);
 564                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 565                 goto drop;
 566         }
 567
 568         daddr = (xfrm_address_t *)(skb_network_header(skb) +
 569                                    XFRM_SPI_SKB_CB(skb)->daddroff);
 570         do {
 571                 sp = skb_sec_path(skb);
 572
 573                 if (sp->len == XFRM_MAX_DEPTH) {
 574                         secpath_reset(skb);
 575                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 576                         goto drop;
 577                 }
 578
 579                 x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
 580                 if (x == NULL) {
 581                         secpath_reset(skb);
 582                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
 583                         xfrm_audit_state_notfound(skb, family, spi, seq);
 584                         goto drop;
 585                 }
 586
 587                 if (unlikely(x->dir && x->dir != XFRM_SA_DIR_IN)) {
 588                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEDIRERROR);
 589                         xfrm_state_put(x);
 590                         goto drop;
 591                 }
 592
 593                 skb->mark = xfrm_smark_get(skb->mark, x);
 594
 595                 sp->xvec[sp->len++] = x;
 596
 597                 skb_dst_force(skb);
 598                 if (!skb_dst(skb)) {
 599                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
 600                         goto drop;
 601                 }
 602
 603 lock:
 604                 spin_lock(&x->lock);
 605
 606                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
 607                         if (x->km.state == XFRM_STATE_ACQ)
 608                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
 609                         else
 610                                 XFRM_INC_STATS(net,
 611                                                LINUX_MIB_XFRMINSTATEINVALID);
 612                         goto drop_unlock;
 613                 }
 614
 615                 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
 616                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
 617                         goto drop_unlock;
 618                 }
 619
 620                 if (xfrm_replay_check(x, skb, seq)) {
 621                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 622                         goto drop_unlock;
 623                 }
 624
 625                 if (xfrm_state_check_expire(x)) {
 626                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
 627                         goto drop_unlock;
 628                 }
 629
 630                 spin_unlock(&x->lock);
 631
 632                 if (xfrm_tunnel_check(skb, x, family)) {
 633                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 634                         goto drop;
 635                 }
 636
 637                 seq_hi = htonl(xfrm_replay_seqhi(x, seq));
 638
 639                 XFRM_SKB_CB(skb)->seq.input.low = seq;
 640                 XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
 641
 642                 dev_hold(skb->dev);
 643
 644                 if (crypto_done)
 645                         nexthdr = x->type_offload->input_tail(x, skb);
 646                 else
 647                         nexthdr = x->type->input(x, skb);
 648
 649                 if (nexthdr == -EINPROGRESS)
 650                         return 0;
 651 resume:
 652                 dev_put(skb->dev);
 653
 654                 spin_lock(&x->lock);
 655                 if (nexthdr < 0) {
 656                         if (nexthdr == -EBADMSG) {
 657                                 xfrm_audit_state_icvfail(x, skb,
 658                                                          x->type->proto);
 659                                 x->stats.integrity_failed++;
 660                         }
 661                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 662                         goto drop_unlock;
 663                 }
 664
 665                 /* only the first xfrm gets the encap type */
 666                 encap_type = 0;
 667
 668                 if (xfrm_replay_recheck(x, skb, seq)) {
 669                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 670                         goto drop_unlock;
 671                 }
 672
 673                 xfrm_replay_advance(x, seq);
 674
 675                 x->curlft.bytes += skb->len;
 676                 x->curlft.packets++;
 677                 x->lastused = ktime_get_real_seconds();
 678
 679                 spin_unlock(&x->lock);
 680
 681                 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
 682
 683                 if (xfrm_inner_mode_input(x, skb)) {
 684                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 685                         goto drop;
 686                 }
 687
 688                 if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
 689                         decaps = 1;
 690                         break;
 691                 }
 692
 693                 /*
 694                  * We need the inner address.  However, we only get here for
 695                  * transport mode so the outer address is identical.
 696                  */
 697                 daddr = &x->id.daddr;
 698                 family = x->props.family;
 699
 700                 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
 701                 if (err < 0) {
 702                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 703                         goto drop;
 704                 }
 705                 crypto_done = false;
 706         } while (!err);
 707
 708         err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
 709         if (err)
 710                 goto drop;
 711
 712         nf_reset_ct(skb);
 713
 714         if (decaps) {
 715                 sp = skb_sec_path(skb);
 716                 if (sp)
 717                         sp->olen = 0;
 718                 if (skb_valid_dst(skb))
 719                         skb_dst_drop(skb);
 720                 gro_cells_receive(&gro_cells, skb);
 721                 return 0;
 722         } else {
 723                 xo = xfrm_offload(skb);
 724                 if (xo)
 725                         xfrm_gro = xo->flags & XFRM_GRO;
 726
 727                 err = -EAFNOSUPPORT;
 728                 rcu_read_lock();
 729                 afinfo = xfrm_state_afinfo_get_rcu(x->props.family);
 730                 if (likely(afinfo))
 731                         err = afinfo->transport_finish(skb, xfrm_gro || async);
 732                 rcu_read_unlock();
 733                 if (xfrm_gro) {
 734                         sp = skb_sec_path(skb);
 735                         if (sp)
 736                                 sp->olen = 0;
 737                         if (skb_valid_dst(skb))
 738                                 skb_dst_drop(skb);
 739                         gro_cells_receive(&gro_cells, skb);
 740                         return err;
 741                 }
 742
 743                 return err;
 744         }
 745
 746 drop_unlock:
 747         spin_unlock(&x->lock);
 748 drop:
 749         xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
 750         kfree_skb(skb);
 751         return 0;
 752 }
 753 EXPORT_SYMBOL(xfrm_input);
 754
 755 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
 756 {
 757         return xfrm_input(skb, nexthdr, 0, -1);
 758 }
 759 EXPORT_SYMBOL(xfrm_input_resume);
 760
 761 static void xfrm_trans_reinject(struct work_struct *work)
 762 {
 763         struct xfrm_trans_tasklet *trans = container_of(work, struct xfrm_trans_tasklet, work);
 764         struct sk_buff_head queue;
 765         struct sk_buff *skb;
 766
 767         __skb_queue_head_init(&queue);
 768         spin_lock_bh(&trans->queue_lock);
 769         skb_queue_splice_init(&trans->queue, &queue);
 770         spin_unlock_bh(&trans->queue_lock);
 771
 772         local_bh_disable();
 773         while ((skb = __skb_dequeue(&queue)))
 774                 XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
 775                                                NULL, skb);
 776         local_bh_enable();
 777 }
 778
 779 int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
 780                          int (*finish)(struct net *, struct sock *,
 781                                        struct sk_buff *))
 782 {
 783         struct xfrm_trans_tasklet *trans;
 784
 785         trans = this_cpu_ptr(&xfrm_trans_tasklet);
 786
 787         if (skb_queue_len(&trans->queue) >= READ_ONCE(net_hotdata.max_backlog))
 788                 return -ENOBUFS;
 789
 790         BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
 791
 792         XFRM_TRANS_SKB_CB(skb)->finish = finish;
 793         XFRM_TRANS_SKB_CB(skb)->net = net;
 794         spin_lock_bh(&trans->queue_lock);
 795         __skb_queue_tail(&trans->queue, skb);
 796         spin_unlock_bh(&trans->queue_lock);
 797         schedule_work(&trans->work);
 798         return 0;
 799 }
 800 EXPORT_SYMBOL(xfrm_trans_queue_net);
 801
 802 int xfrm_trans_queue(struct sk_buff *skb,
 803                      int (*finish)(struct net *, struct sock *,
 804                                    struct sk_buff *))
 805 {
 806         return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
 807 }
 808 EXPORT_SYMBOL(xfrm_trans_queue);
 809
 810 void __init xfrm_input_init(void)
 811 {
 812         int err;
 813         int i;
 814
 815         init_dummy_netdev(&xfrm_napi_dev);
 816         err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
 817         if (err)
 818                 gro_cells.cells = NULL;
 819
 820         for_each_possible_cpu(i) {
 821                 struct xfrm_trans_tasklet *trans;
 822
 823                 trans = &per_cpu(xfrm_trans_tasklet, i);
 824                 spin_lock_init(&trans->queue_lock);
 825                 __skb_queue_head_init(&trans->queue);
 826                 INIT_WORK(&trans->work, xfrm_trans_reinject);
 827         }
 828 }