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 work_struct work;
  28         spinlock_t queue_lock;
  29         struct sk_buff_head queue;
  30 };
  31
  32 struct xfrm_trans_cb {
  33         union {
  34                 struct inet_skb_parm    h4;
  35 #if IS_ENABLED(CONFIG_IPV6)
  36                 struct inet6_skb_parm   h6;
  37 #endif
  38         } header;
  39         int (*finish)(struct net *net, struct sock *sk, struct sk_buff *skb);
  40         struct net *net;
  41 };
  42
  43 #define XFRM_TRANS_SKB_CB(__skb) ((struct xfrm_trans_cb *)&((__skb)->cb[0]))
  44
  45 static DEFINE_SPINLOCK(xfrm_input_afinfo_lock);
  46 static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[2][AF_INET6 + 1];
  47
  48 static struct gro_cells gro_cells;
  49 static struct net_device xfrm_napi_dev;
  50
  51 static DEFINE_PER_CPU(struct xfrm_trans_tasklet, xfrm_trans_tasklet);
  52
  53 int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo)
  54 {
  55         int err = 0;
  56
  57         if (WARN_ON(afinfo->family > AF_INET6))
  58                 return -EAFNOSUPPORT;
  59
  60         spin_lock_bh(&xfrm_input_afinfo_lock);
  61         if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family]))
  62                 err = -EEXIST;
  63         else
  64                 rcu_assign_pointer(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], afinfo);
  65         spin_unlock_bh(&xfrm_input_afinfo_lock);
  66         return err;
  67 }
  68 EXPORT_SYMBOL(xfrm_input_register_afinfo);
  69
  70 int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo)
  71 {
  72         int err = 0;
  73
  74         spin_lock_bh(&xfrm_input_afinfo_lock);
  75         if (likely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family])) {
  76                 if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family] != afinfo))
  77                         err = -EINVAL;
  78                 else
  79                         RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], NULL);
  80         }
  81         spin_unlock_bh(&xfrm_input_afinfo_lock);
  82         synchronize_rcu();
  83         return err;
  84 }
  85 EXPORT_SYMBOL(xfrm_input_unregister_afinfo);
  86
  87 static const struct xfrm_input_afinfo *xfrm_input_get_afinfo(u8 family, bool is_ipip)
  88 {
  89         const struct xfrm_input_afinfo *afinfo;
  90
  91         if (WARN_ON_ONCE(family > AF_INET6))
  92                 return NULL;
  93
  94         rcu_read_lock();
  95         afinfo = rcu_dereference(xfrm_input_afinfo[is_ipip][family]);
  96         if (unlikely(!afinfo))
  97                 rcu_read_unlock();
  98         return afinfo;
  99 }
 100
 101 static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
 102                        int err)
 103 {
 104         bool is_ipip = (protocol == IPPROTO_IPIP || protocol == IPPROTO_IPV6);
 105         const struct xfrm_input_afinfo *afinfo;
 106         int ret;
 107
 108         afinfo = xfrm_input_get_afinfo(family, is_ipip);
 109         if (!afinfo)
 110                 return -EAFNOSUPPORT;
 111
 112         ret = afinfo->callback(skb, protocol, err);
 113         rcu_read_unlock();
 114
 115         return ret;
 116 }
 117
 118 struct sec_path *secpath_set(struct sk_buff *skb)
 119 {
 120         struct sec_path *sp, *tmp = skb_ext_find(skb, SKB_EXT_SEC_PATH);
 121
 122         sp = skb_ext_add(skb, SKB_EXT_SEC_PATH);
 123         if (!sp)
 124                 return NULL;
 125
 126         if (tmp) /* reused existing one (was COW'd if needed) */
 127                 return sp;
 128
 129         /* allocated new secpath */
 130         memset(sp->ovec, 0, sizeof(sp->ovec));
 131         sp->olen = 0;
 132         sp->len = 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(ipv6_get_dsfield(ipv6_hdr(skb)),
 282                                ipipv6_hdr(skb));
 283         if (!(x->props.flags & XFRM_STATE_NOECN))
 284                 ipip6_ecn_decapsulate(skb);
 285
 286         skb_reset_network_header(skb);
 287         skb_mac_header_rebuild(skb);
 288         if (skb->mac_len)
 289                 eth_hdr(skb)->h_proto = skb->protocol;
 290
 291         err = 0;
 292
 293 out:
 294         return err;
 295 }
 296
 297 static int xfrm6_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
 298 {
 299         struct ipv6hdr *ip6h;
 300         int size = sizeof(struct ipv6hdr);
 301         int err;
 302
 303         err = skb_cow_head(skb, size + skb->mac_len);
 304         if (err)
 305                 goto out;
 306
 307         __skb_push(skb, size);
 308         skb_reset_network_header(skb);
 309         skb_mac_header_rebuild(skb);
 310
 311         xfrm6_beet_make_header(skb);
 312
 313         ip6h = ipv6_hdr(skb);
 314         ip6h->payload_len = htons(skb->len - size);
 315         ip6h->daddr = x->sel.daddr.in6;
 316         ip6h->saddr = x->sel.saddr.in6;
 317         err = 0;
 318 out:
 319         return err;
 320 }
 321
 322 /* Remove encapsulation header.
 323  *
 324  * The IP header will be moved over the top of the encapsulation
 325  * header.
 326  *
 327  * On entry, the transport header shall point to where the IP header
 328  * should be and the network header shall be set to where the IP
 329  * header currently is.  skb->data shall point to the start of the
 330  * payload.
 331  */
 332 static int
 333 xfrm_inner_mode_encap_remove(struct xfrm_state *x,
 334                              const struct xfrm_mode *inner_mode,
 335                              struct sk_buff *skb)
 336 {
 337         switch (inner_mode->encap) {
 338         case XFRM_MODE_BEET:
 339                 if (inner_mode->family == AF_INET)
 340                         return xfrm4_remove_beet_encap(x, skb);
 341                 if (inner_mode->family == AF_INET6)
 342                         return xfrm6_remove_beet_encap(x, skb);
 343                 break;
 344         case XFRM_MODE_TUNNEL:
 345                 if (inner_mode->family == AF_INET)
 346                         return xfrm4_remove_tunnel_encap(x, skb);
 347                 if (inner_mode->family == AF_INET6)
 348                         return xfrm6_remove_tunnel_encap(x, skb);
 349                 break;
 350         }
 351
 352         WARN_ON_ONCE(1);
 353         return -EOPNOTSUPP;
 354 }
 355
 356 static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 357 {
 358         const struct xfrm_mode *inner_mode = &x->inner_mode;
 359
 360         switch (x->outer_mode.family) {
 361         case AF_INET:
 362                 xfrm4_extract_header(skb);
 363                 break;
 364         case AF_INET6:
 365                 xfrm6_extract_header(skb);
 366                 break;
 367         default:
 368                 WARN_ON_ONCE(1);
 369                 return -EAFNOSUPPORT;
 370         }
 371
 372         if (x->sel.family == AF_UNSPEC) {
 373                 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
 374                 if (!inner_mode)
 375                         return -EAFNOSUPPORT;
 376         }
 377
 378         switch (inner_mode->family) {
 379         case AF_INET:
 380                 skb->protocol = htons(ETH_P_IP);
 381                 break;
 382         case AF_INET6:
 383                 skb->protocol = htons(ETH_P_IPV6);
 384                 break;
 385         default:
 386                 WARN_ON_ONCE(1);
 387                 break;
 388         }
 389
 390         return xfrm_inner_mode_encap_remove(x, inner_mode, skb);
 391 }
 392
 393 /* Remove encapsulation header.
 394  *
 395  * The IP header will be moved over the top of the encapsulation header.
 396  *
 397  * On entry, skb_transport_header() shall point to where the IP header
 398  * should be and skb_network_header() shall be set to where the IP header
 399  * currently is.  skb->data shall point to the start of the payload.
 400  */
 401 static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 402 {
 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                 skb->network_header = skb->transport_header;
 409         }
 410         ip_hdr(skb)->tot_len = htons(skb->len + ihl);
 411         skb_reset_transport_header(skb);
 412         return 0;
 413 }
 414
 415 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 416 {
 417 #if IS_ENABLED(CONFIG_IPV6)
 418         int ihl = skb->data - skb_transport_header(skb);
 419
 420         if (skb->transport_header != skb->network_header) {
 421                 memmove(skb_transport_header(skb),
 422                         skb_network_header(skb), ihl);
 423                 skb->network_header = skb->transport_header;
 424         }
 425         ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
 426                                            sizeof(struct ipv6hdr));
 427         skb_reset_transport_header(skb);
 428         return 0;
 429 #else
 430         WARN_ON_ONCE(1);
 431         return -EAFNOSUPPORT;
 432 #endif
 433 }
 434
 435 static int xfrm_inner_mode_input(struct xfrm_state *x,
 436                                  const struct xfrm_mode *inner_mode,
 437                                  struct sk_buff *skb)
 438 {
 439         switch (inner_mode->encap) {
 440         case XFRM_MODE_BEET:
 441         case XFRM_MODE_TUNNEL:
 442                 return xfrm_prepare_input(x, skb);
 443         case XFRM_MODE_TRANSPORT:
 444                 if (inner_mode->family == AF_INET)
 445                         return xfrm4_transport_input(x, skb);
 446                 if (inner_mode->family == AF_INET6)
 447                         return xfrm6_transport_input(x, skb);
 448                 break;
 449         case XFRM_MODE_ROUTEOPTIMIZATION:
 450                 WARN_ON_ONCE(1);
 451                 break;
 452         default:
 453                 WARN_ON_ONCE(1);
 454                 break;
 455         }
 456
 457         return -EOPNOTSUPP;
 458 }
 459
 460 int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 461 {
 462         const struct xfrm_state_afinfo *afinfo;
 463         struct net *net = dev_net(skb->dev);
 464         const struct xfrm_mode *inner_mode;
 465         int err;
 466         __be32 seq;
 467         __be32 seq_hi;
 468         struct xfrm_state *x = NULL;
 469         xfrm_address_t *daddr;
 470         u32 mark = skb->mark;
 471         unsigned int family = AF_UNSPEC;
 472         int decaps = 0;
 473         int async = 0;
 474         bool xfrm_gro = false;
 475         bool crypto_done = false;
 476         struct xfrm_offload *xo = xfrm_offload(skb);
 477         struct sec_path *sp;
 478
 479         if (encap_type < 0) {
 480                 x = xfrm_input_state(skb);
 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->outer_mode.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
 503                 /* encap_type < -1 indicates a GRO call. */
 504                 encap_type = 0;
 505                 seq = XFRM_SPI_SKB_CB(skb)->seq;
 506
 507                 if (xo && (xo->flags & CRYPTO_DONE)) {
 508                         crypto_done = true;
 509                         family = XFRM_SPI_SKB_CB(skb)->family;
 510
 511                         if (!(xo->status & CRYPTO_SUCCESS)) {
 512                                 if (xo->status &
 513                                     (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
 514                                      CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
 515                                      CRYPTO_TUNNEL_AH_AUTH_FAILED |
 516                                      CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
 517
 518                                         xfrm_audit_state_icvfail(x, skb,
 519                                                                  x->type->proto);
 520                                         x->stats.integrity_failed++;
 521                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 522                                         goto drop;
 523                                 }
 524
 525                                 if (xo->status & CRYPTO_INVALID_PROTOCOL) {
 526                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 527                                         goto drop;
 528                                 }
 529
 530                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 531                                 goto drop;
 532                         }
 533
 534                         if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
 535                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 536                                 goto drop;
 537                         }
 538                 }
 539
 540                 goto lock;
 541         }
 542
 543         family = XFRM_SPI_SKB_CB(skb)->family;
 544
 545         /* if tunnel is present override skb->mark value with tunnel i_key */
 546         switch (family) {
 547         case AF_INET:
 548                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
 549                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
 550                 break;
 551         case AF_INET6:
 552                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
 553                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
 554                 break;
 555         }
 556
 557         sp = secpath_set(skb);
 558         if (!sp) {
 559                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
 560                 goto drop;
 561         }
 562
 563         seq = 0;
 564         if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
 565                 secpath_reset(skb);
 566                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 567                 goto drop;
 568         }
 569
 570         daddr = (xfrm_address_t *)(skb_network_header(skb) +
 571                                    XFRM_SPI_SKB_CB(skb)->daddroff);
 572         do {
 573                 sp = skb_sec_path(skb);
 574
 575                 if (sp->len == XFRM_MAX_DEPTH) {
 576                         secpath_reset(skb);
 577                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 578                         goto drop;
 579                 }
 580
 581                 x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
 582                 if (x == NULL) {
 583                         secpath_reset(skb);
 584                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
 585                         xfrm_audit_state_notfound(skb, family, spi, seq);
 586                         goto drop;
 587                 }
 588
 589                 skb->mark = xfrm_smark_get(skb->mark, x);
 590
 591                 sp->xvec[sp->len++] = x;
 592
 593                 skb_dst_force(skb);
 594                 if (!skb_dst(skb)) {
 595                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
 596                         goto drop;
 597                 }
 598
 599 lock:
 600                 spin_lock(&x->lock);
 601
 602                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
 603                         if (x->km.state == XFRM_STATE_ACQ)
 604                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
 605                         else
 606                                 XFRM_INC_STATS(net,
 607                                                LINUX_MIB_XFRMINSTATEINVALID);
 608                         goto drop_unlock;
 609                 }
 610
 611                 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
 612                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
 613                         goto drop_unlock;
 614                 }
 615
 616                 if (xfrm_replay_check(x, skb, seq)) {
 617                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 618                         goto drop_unlock;
 619                 }
 620
 621                 if (xfrm_state_check_expire(x)) {
 622                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
 623                         goto drop_unlock;
 624                 }
 625
 626                 spin_unlock(&x->lock);
 627
 628                 if (xfrm_tunnel_check(skb, x, family)) {
 629                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 630                         goto drop;
 631                 }
 632
 633                 seq_hi = htonl(xfrm_replay_seqhi(x, seq));
 634
 635                 XFRM_SKB_CB(skb)->seq.input.low = seq;
 636                 XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
 637
 638                 dev_hold(skb->dev);
 639
 640                 if (crypto_done)
 641                         nexthdr = x->type_offload->input_tail(x, skb);
 642                 else
 643                         nexthdr = x->type->input(x, skb);
 644
 645                 if (nexthdr == -EINPROGRESS)
 646                         return 0;
 647 resume:
 648                 dev_put(skb->dev);
 649
 650                 spin_lock(&x->lock);
 651                 if (nexthdr < 0) {
 652                         if (nexthdr == -EBADMSG) {
 653                                 xfrm_audit_state_icvfail(x, skb,
 654                                                          x->type->proto);
 655                                 x->stats.integrity_failed++;
 656                         }
 657                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 658                         goto drop_unlock;
 659                 }
 660
 661                 /* only the first xfrm gets the encap type */
 662                 encap_type = 0;
 663
 664                 if (xfrm_replay_recheck(x, skb, seq)) {
 665                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 666                         goto drop_unlock;
 667                 }
 668
 669                 xfrm_replay_advance(x, seq);
 670
 671                 x->curlft.bytes += skb->len;
 672                 x->curlft.packets++;
 673
 674                 spin_unlock(&x->lock);
 675
 676                 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
 677
 678                 inner_mode = &x->inner_mode;
 679
 680                 if (x->sel.family == AF_UNSPEC) {
 681                         inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
 682                         if (inner_mode == NULL) {
 683                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 684                                 goto drop;
 685                         }
 686                 }
 687
 688                 if (xfrm_inner_mode_input(x, inner_mode, skb)) {
 689                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 690                         goto drop;
 691                 }
 692
 693                 if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
 694                         decaps = 1;
 695                         break;
 696                 }
 697
 698                 /*
 699                  * We need the inner address.  However, we only get here for
 700                  * transport mode so the outer address is identical.
 701                  */
 702                 daddr = &x->id.daddr;
 703                 family = x->outer_mode.family;
 704
 705                 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
 706                 if (err < 0) {
 707                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 708                         goto drop;
 709                 }
 710                 crypto_done = false;
 711         } while (!err);
 712
 713         err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
 714         if (err)
 715                 goto drop;
 716
 717         nf_reset_ct(skb);
 718
 719         if (decaps) {
 720                 sp = skb_sec_path(skb);
 721                 if (sp)
 722                         sp->olen = 0;
 723                 skb_dst_drop(skb);
 724                 gro_cells_receive(&gro_cells, skb);
 725                 return 0;
 726         } else {
 727                 xo = xfrm_offload(skb);
 728                 if (xo)
 729                         xfrm_gro = xo->flags & XFRM_GRO;
 730
 731                 err = -EAFNOSUPPORT;
 732                 rcu_read_lock();
 733                 afinfo = xfrm_state_afinfo_get_rcu(x->inner_mode.family);
 734                 if (likely(afinfo))
 735                         err = afinfo->transport_finish(skb, xfrm_gro || async);
 736                 rcu_read_unlock();
 737                 if (xfrm_gro) {
 738                         sp = skb_sec_path(skb);
 739                         if (sp)
 740                                 sp->olen = 0;
 741                         skb_dst_drop(skb);
 742                         gro_cells_receive(&gro_cells, skb);
 743                         return err;
 744                 }
 745
 746                 return err;
 747         }
 748
 749 drop_unlock:
 750         spin_unlock(&x->lock);
 751 drop:
 752         xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
 753         kfree_skb(skb);
 754         return 0;
 755 }
 756 EXPORT_SYMBOL(xfrm_input);
 757
 758 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
 759 {
 760         return xfrm_input(skb, nexthdr, 0, -1);
 761 }
 762 EXPORT_SYMBOL(xfrm_input_resume);
 763
 764 static void xfrm_trans_reinject(struct work_struct *work)
 765 {
 766         struct xfrm_trans_tasklet *trans = container_of(work, struct xfrm_trans_tasklet, work);
 767         struct sk_buff_head queue;
 768         struct sk_buff *skb;
 769
 770         __skb_queue_head_init(&queue);
 771         spin_lock_bh(&trans->queue_lock);
 772         skb_queue_splice_init(&trans->queue, &queue);
 773         spin_unlock_bh(&trans->queue_lock);
 774
 775         local_bh_disable();
 776         while ((skb = __skb_dequeue(&queue)))
 777                 XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
 778                                                NULL, skb);
 779         local_bh_enable();
 780 }
 781
 782 int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
 783                          int (*finish)(struct net *, struct sock *,
 784                                        struct sk_buff *))
 785 {
 786         struct xfrm_trans_tasklet *trans;
 787
 788         trans = this_cpu_ptr(&xfrm_trans_tasklet);
 789
 790         if (skb_queue_len(&trans->queue) >= READ_ONCE(netdev_max_backlog))
 791                 return -ENOBUFS;
 792
 793         BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
 794
 795         XFRM_TRANS_SKB_CB(skb)->finish = finish;
 796         XFRM_TRANS_SKB_CB(skb)->net = net;
 797         spin_lock_bh(&trans->queue_lock);
 798         __skb_queue_tail(&trans->queue, skb);
 799         spin_unlock_bh(&trans->queue_lock);
 800         schedule_work(&trans->work);
 801         return 0;
 802 }
 803 EXPORT_SYMBOL(xfrm_trans_queue_net);
 804
 805 int xfrm_trans_queue(struct sk_buff *skb,
 806                      int (*finish)(struct net *, struct sock *,
 807                                    struct sk_buff *))
 808 {
 809         return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
 810 }
 811 EXPORT_SYMBOL(xfrm_trans_queue);
 812
 813 void __init xfrm_input_init(void)
 814 {
 815         int err;
 816         int i;
 817
 818         init_dummy_netdev(&xfrm_napi_dev);
 819         err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
 820         if (err)
 821                 gro_cells.cells = NULL;
 822
 823         for_each_possible_cpu(i) {
 824                 struct xfrm_trans_tasklet *trans;
 825
 826                 trans = &per_cpu(xfrm_trans_tasklet, i);
 827                 spin_lock_init(&trans->queue_lock);
 828                 __skb_queue_head_init(&trans->queue);
 829                 INIT_WORK(&trans->work, xfrm_trans_reinject);
 830         }
 831 }