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
  25 #include "xfrm_inout.h"
  26
  27 struct xfrm_trans_tasklet {
  28         struct work_struct work;
  29         spinlock_t queue_lock;
  30         struct sk_buff_head queue;
  31 };
  32
  33 struct xfrm_trans_cb {
  34         union {
  35                 struct inet_skb_parm    h4;
  36 #if IS_ENABLED(CONFIG_IPV6)
  37                 struct inet6_skb_parm   h6;
  38 #endif
  39         } header;
  40         int (*finish)(struct net *net, struct sock *sk, struct sk_buff *skb);
  41         struct net *net;
  42 };
  43
  44 #define XFRM_TRANS_SKB_CB(__skb) ((struct xfrm_trans_cb *)&((__skb)->cb[0]))
  45
  46 static DEFINE_SPINLOCK(xfrm_input_afinfo_lock);
  47 static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[2][AF_INET6 + 1];
  48
  49 static struct gro_cells gro_cells;
  50 static struct net_device xfrm_napi_dev;
  51
  52 static DEFINE_PER_CPU(struct xfrm_trans_tasklet, xfrm_trans_tasklet);
  53
  54 int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo)
  55 {
  56         int err = 0;
  57
  58         if (WARN_ON(afinfo->family > AF_INET6))
  59                 return -EAFNOSUPPORT;
  60
  61         spin_lock_bh(&xfrm_input_afinfo_lock);
  62         if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family]))
  63                 err = -EEXIST;
  64         else
  65                 rcu_assign_pointer(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], afinfo);
  66         spin_unlock_bh(&xfrm_input_afinfo_lock);
  67         return err;
  68 }
  69 EXPORT_SYMBOL(xfrm_input_register_afinfo);
  70
  71 int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo)
  72 {
  73         int err = 0;
  74
  75         spin_lock_bh(&xfrm_input_afinfo_lock);
  76         if (likely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family])) {
  77                 if (unlikely(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family] != afinfo))
  78                         err = -EINVAL;
  79                 else
  80                         RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->is_ipip][afinfo->family], NULL);
  81         }
  82         spin_unlock_bh(&xfrm_input_afinfo_lock);
  83         synchronize_rcu();
  84         return err;
  85 }
  86 EXPORT_SYMBOL(xfrm_input_unregister_afinfo);
  87
  88 static const struct xfrm_input_afinfo *xfrm_input_get_afinfo(u8 family, bool is_ipip)
  89 {
  90         const struct xfrm_input_afinfo *afinfo;
  91
  92         if (WARN_ON_ONCE(family > AF_INET6))
  93                 return NULL;
  94
  95         rcu_read_lock();
  96         afinfo = rcu_dereference(xfrm_input_afinfo[is_ipip][family]);
  97         if (unlikely(!afinfo))
  98                 rcu_read_unlock();
  99         return afinfo;
 100 }
 101
 102 static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
 103                        int err)
 104 {
 105         bool is_ipip = (protocol == IPPROTO_IPIP || protocol == IPPROTO_IPV6);
 106         const struct xfrm_input_afinfo *afinfo;
 107         int ret;
 108
 109         afinfo = xfrm_input_get_afinfo(family, is_ipip);
 110         if (!afinfo)
 111                 return -EAFNOSUPPORT;
 112
 113         ret = afinfo->callback(skb, protocol, err);
 114         rcu_read_unlock();
 115
 116         return ret;
 117 }
 118
 119 struct sec_path *secpath_set(struct sk_buff *skb)
 120 {
 121         struct sec_path *sp, *tmp = skb_ext_find(skb, SKB_EXT_SEC_PATH);
 122
 123         sp = skb_ext_add(skb, SKB_EXT_SEC_PATH);
 124         if (!sp)
 125                 return NULL;
 126
 127         if (tmp) /* reused existing one (was COW'd if needed) */
 128                 return sp;
 129
 130         /* allocated new secpath */
 131         memset(sp->ovec, 0, sizeof(sp->ovec));
 132         sp->olen = 0;
 133         sp->len = 0;
 134         sp->verified_cnt = 0;
 135
 136         return sp;
 137 }
 138 EXPORT_SYMBOL(secpath_set);
 139
 140 /* Fetch spi and seq from ipsec header */
 141
 142 int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
 143 {
 144         int offset, offset_seq;
 145         int hlen;
 146
 147         switch (nexthdr) {
 148         case IPPROTO_AH:
 149                 hlen = sizeof(struct ip_auth_hdr);
 150                 offset = offsetof(struct ip_auth_hdr, spi);
 151                 offset_seq = offsetof(struct ip_auth_hdr, seq_no);
 152                 break;
 153         case IPPROTO_ESP:
 154                 hlen = sizeof(struct ip_esp_hdr);
 155                 offset = offsetof(struct ip_esp_hdr, spi);
 156                 offset_seq = offsetof(struct ip_esp_hdr, seq_no);
 157                 break;
 158         case IPPROTO_COMP:
 159                 if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
 160                         return -EINVAL;
 161                 *spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2)));
 162                 *seq = 0;
 163                 return 0;
 164         default:
 165                 return 1;
 166         }
 167
 168         if (!pskb_may_pull(skb, hlen))
 169                 return -EINVAL;
 170
 171         *spi = *(__be32 *)(skb_transport_header(skb) + offset);
 172         *seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
 173         return 0;
 174 }
 175 EXPORT_SYMBOL(xfrm_parse_spi);
 176
 177 static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
 178 {
 179         struct iphdr *iph;
 180         int optlen = 0;
 181         int err = -EINVAL;
 182
 183         if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
 184                 struct ip_beet_phdr *ph;
 185                 int phlen;
 186
 187                 if (!pskb_may_pull(skb, sizeof(*ph)))
 188                         goto out;
 189
 190                 ph = (struct ip_beet_phdr *)skb->data;
 191
 192                 phlen = sizeof(*ph) + ph->padlen;
 193                 optlen = ph->hdrlen * 8 + (IPV4_BEET_PHMAXLEN - phlen);
 194                 if (optlen < 0 || optlen & 3 || optlen > 250)
 195                         goto out;
 196
 197                 XFRM_MODE_SKB_CB(skb)->protocol = ph->nexthdr;
 198
 199                 if (!pskb_may_pull(skb, phlen))
 200                         goto out;
 201                 __skb_pull(skb, phlen);
 202         }
 203
 204         skb_push(skb, sizeof(*iph));
 205         skb_reset_network_header(skb);
 206         skb_mac_header_rebuild(skb);
 207
 208         xfrm4_beet_make_header(skb);
 209
 210         iph = ip_hdr(skb);
 211
 212         iph->ihl += optlen / 4;
 213         iph->tot_len = htons(skb->len);
 214         iph->daddr = x->sel.daddr.a4;
 215         iph->saddr = x->sel.saddr.a4;
 216         iph->check = 0;
 217         iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
 218         err = 0;
 219 out:
 220         return err;
 221 }
 222
 223 static void ipip_ecn_decapsulate(struct sk_buff *skb)
 224 {
 225         struct iphdr *inner_iph = ipip_hdr(skb);
 226
 227         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
 228                 IP_ECN_set_ce(inner_iph);
 229 }
 230
 231 static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 232 {
 233         int err = -EINVAL;
 234
 235         if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
 236                 goto out;
 237
 238         if (!pskb_may_pull(skb, sizeof(struct iphdr)))
 239                 goto out;
 240
 241         err = skb_unclone(skb, GFP_ATOMIC);
 242         if (err)
 243                 goto out;
 244
 245         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
 246                 ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
 247         if (!(x->props.flags & XFRM_STATE_NOECN))
 248                 ipip_ecn_decapsulate(skb);
 249
 250         skb_reset_network_header(skb);
 251         skb_mac_header_rebuild(skb);
 252         if (skb->mac_len)
 253                 eth_hdr(skb)->h_proto = skb->protocol;
 254
 255         err = 0;
 256
 257 out:
 258         return err;
 259 }
 260
 261 static void ipip6_ecn_decapsulate(struct sk_buff *skb)
 262 {
 263         struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
 264
 265         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
 266                 IP6_ECN_set_ce(skb, inner_iph);
 267 }
 268
 269 static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 270 {
 271         int err = -EINVAL;
 272
 273         if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
 274                 goto out;
 275         if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
 276                 goto out;
 277
 278         err = skb_unclone(skb, GFP_ATOMIC);
 279         if (err)
 280                 goto out;
 281
 282         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
 283                 ipv6_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipipv6_hdr(skb));
 284         if (!(x->props.flags & XFRM_STATE_NOECN))
 285                 ipip6_ecn_decapsulate(skb);
 286
 287         skb_reset_network_header(skb);
 288         skb_mac_header_rebuild(skb);
 289         if (skb->mac_len)
 290                 eth_hdr(skb)->h_proto = skb->protocol;
 291
 292         err = 0;
 293
 294 out:
 295         return err;
 296 }
 297
 298 static int xfrm6_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
 299 {
 300         struct ipv6hdr *ip6h;
 301         int size = sizeof(struct ipv6hdr);
 302         int err;
 303
 304         err = skb_cow_head(skb, size + skb->mac_len);
 305         if (err)
 306                 goto out;
 307
 308         __skb_push(skb, size);
 309         skb_reset_network_header(skb);
 310         skb_mac_header_rebuild(skb);
 311
 312         xfrm6_beet_make_header(skb);
 313
 314         ip6h = ipv6_hdr(skb);
 315         ip6h->payload_len = htons(skb->len - size);
 316         ip6h->daddr = x->sel.daddr.in6;
 317         ip6h->saddr = x->sel.saddr.in6;
 318         err = 0;
 319 out:
 320         return err;
 321 }
 322
 323 /* Remove encapsulation header.
 324  *
 325  * The IP header will be moved over the top of the encapsulation
 326  * header.
 327  *
 328  * On entry, the transport header shall point to where the IP header
 329  * should be and the network header shall be set to where the IP
 330  * header currently is.  skb->data shall point to the start of the
 331  * payload.
 332  */
 333 static int
 334 xfrm_inner_mode_encap_remove(struct xfrm_state *x,
 335                              const struct xfrm_mode *inner_mode,
 336                              struct sk_buff *skb)
 337 {
 338         switch (inner_mode->encap) {
 339         case XFRM_MODE_BEET:
 340                 if (inner_mode->family == AF_INET)
 341                         return xfrm4_remove_beet_encap(x, skb);
 342                 if (inner_mode->family == AF_INET6)
 343                         return xfrm6_remove_beet_encap(x, skb);
 344                 break;
 345         case XFRM_MODE_TUNNEL:
 346                 if (inner_mode->family == AF_INET)
 347                         return xfrm4_remove_tunnel_encap(x, skb);
 348                 if (inner_mode->family == AF_INET6)
 349                         return xfrm6_remove_tunnel_encap(x, skb);
 350                 break;
 351         }
 352
 353         WARN_ON_ONCE(1);
 354         return -EOPNOTSUPP;
 355 }
 356
 357 static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 358 {
 359         const struct xfrm_mode *inner_mode = &x->inner_mode;
 360
 361         switch (x->outer_mode.family) {
 362         case AF_INET:
 363                 xfrm4_extract_header(skb);
 364                 break;
 365         case AF_INET6:
 366                 xfrm6_extract_header(skb);
 367                 break;
 368         default:
 369                 WARN_ON_ONCE(1);
 370                 return -EAFNOSUPPORT;
 371         }
 372
 373         if (x->sel.family == AF_UNSPEC) {
 374                 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
 375                 if (!inner_mode)
 376                         return -EAFNOSUPPORT;
 377         }
 378
 379         switch (inner_mode->family) {
 380         case AF_INET:
 381                 skb->protocol = htons(ETH_P_IP);
 382                 break;
 383         case AF_INET6:
 384                 skb->protocol = htons(ETH_P_IPV6);
 385                 break;
 386         default:
 387                 WARN_ON_ONCE(1);
 388                 break;
 389         }
 390
 391         return xfrm_inner_mode_encap_remove(x, inner_mode, skb);
 392 }
 393
 394 /* Remove encapsulation header.
 395  *
 396  * The IP header will be moved over the top of the encapsulation header.
 397  *
 398  * On entry, skb_transport_header() shall point to where the IP header
 399  * should be and skb_network_header() shall be set to where the IP header
 400  * currently is.  skb->data shall point to the start of the payload.
 401  */
 402 static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 403 {
 404         int ihl = skb->data - skb_transport_header(skb);
 405
 406         if (skb->transport_header != skb->network_header) {
 407                 memmove(skb_transport_header(skb),
 408                         skb_network_header(skb), ihl);
 409                 skb->network_header = skb->transport_header;
 410         }
 411         ip_hdr(skb)->tot_len = htons(skb->len + ihl);
 412         skb_reset_transport_header(skb);
 413         return 0;
 414 }
 415
 416 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 417 {
 418 #if IS_ENABLED(CONFIG_IPV6)
 419         int ihl = skb->data - skb_transport_header(skb);
 420
 421         if (skb->transport_header != skb->network_header) {
 422                 memmove(skb_transport_header(skb),
 423                         skb_network_header(skb), ihl);
 424                 skb->network_header = skb->transport_header;
 425         }
 426         ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
 427                                            sizeof(struct ipv6hdr));
 428         skb_reset_transport_header(skb);
 429         return 0;
 430 #else
 431         WARN_ON_ONCE(1);
 432         return -EAFNOSUPPORT;
 433 #endif
 434 }
 435
 436 static int xfrm_inner_mode_input(struct xfrm_state *x,
 437                                  const struct xfrm_mode *inner_mode,
 438                                  struct sk_buff *skb)
 439 {
 440         switch (inner_mode->encap) {
 441         case XFRM_MODE_BEET:
 442         case XFRM_MODE_TUNNEL:
 443                 return xfrm_prepare_input(x, skb);
 444         case XFRM_MODE_TRANSPORT:
 445                 if (inner_mode->family == AF_INET)
 446                         return xfrm4_transport_input(x, skb);
 447                 if (inner_mode->family == AF_INET6)
 448                         return xfrm6_transport_input(x, skb);
 449                 break;
 450         case XFRM_MODE_ROUTEOPTIMIZATION:
 451                 WARN_ON_ONCE(1);
 452                 break;
 453         default:
 454                 WARN_ON_ONCE(1);
 455                 break;
 456         }
 457
 458         return -EOPNOTSUPP;
 459 }
 460
 461 int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 462 {
 463         const struct xfrm_state_afinfo *afinfo;
 464         struct net *net = dev_net(skb->dev);
 465         const struct xfrm_mode *inner_mode;
 466         int err;
 467         __be32 seq;
 468         __be32 seq_hi;
 469         struct xfrm_state *x = NULL;
 470         xfrm_address_t *daddr;
 471         u32 mark = skb->mark;
 472         unsigned int family = AF_UNSPEC;
 473         int decaps = 0;
 474         int async = 0;
 475         bool xfrm_gro = false;
 476         bool crypto_done = false;
 477         struct xfrm_offload *xo = xfrm_offload(skb);
 478         struct sec_path *sp;
 479
 480         if (encap_type < 0) {
 481                 x = xfrm_input_state(skb);
 482
 483                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
 484                         if (x->km.state == XFRM_STATE_ACQ)
 485                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
 486                         else
 487                                 XFRM_INC_STATS(net,
 488                                                LINUX_MIB_XFRMINSTATEINVALID);
 489
 490                         if (encap_type == -1)
 491                                 dev_put(skb->dev);
 492                         goto drop;
 493                 }
 494
 495                 family = x->outer_mode.family;
 496
 497                 /* An encap_type of -1 indicates async resumption. */
 498                 if (encap_type == -1) {
 499                         async = 1;
 500                         seq = XFRM_SKB_CB(skb)->seq.input.low;
 501                         goto resume;
 502                 }
 503
 504                 /* encap_type < -1 indicates a GRO call. */
 505                 encap_type = 0;
 506                 seq = XFRM_SPI_SKB_CB(skb)->seq;
 507
 508                 if (xo && (xo->flags & CRYPTO_DONE)) {
 509                         crypto_done = true;
 510                         family = XFRM_SPI_SKB_CB(skb)->family;
 511
 512                         if (!(xo->status & CRYPTO_SUCCESS)) {
 513                                 if (xo->status &
 514                                     (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
 515                                      CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
 516                                      CRYPTO_TUNNEL_AH_AUTH_FAILED |
 517                                      CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
 518
 519                                         xfrm_audit_state_icvfail(x, skb,
 520                                                                  x->type->proto);
 521                                         x->stats.integrity_failed++;
 522                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 523                                         goto drop;
 524                                 }
 525
 526                                 if (xo->status & CRYPTO_INVALID_PROTOCOL) {
 527                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 528                                         goto drop;
 529                                 }
 530
 531                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 532                                 goto drop;
 533                         }
 534
 535                         if (xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
 536                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 537                                 goto drop;
 538                         }
 539                 }
 540
 541                 goto lock;
 542         }
 543
 544         family = XFRM_SPI_SKB_CB(skb)->family;
 545
 546         /* if tunnel is present override skb->mark value with tunnel i_key */
 547         switch (family) {
 548         case AF_INET:
 549                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
 550                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
 551                 break;
 552         case AF_INET6:
 553                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
 554                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
 555                 break;
 556         }
 557
 558         sp = secpath_set(skb);
 559         if (!sp) {
 560                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
 561                 goto drop;
 562         }
 563
 564         seq = 0;
 565         if (!spi && xfrm_parse_spi(skb, nexthdr, &spi, &seq)) {
 566                 secpath_reset(skb);
 567                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 568                 goto drop;
 569         }
 570
 571         daddr = (xfrm_address_t *)(skb_network_header(skb) +
 572                                    XFRM_SPI_SKB_CB(skb)->daddroff);
 573         do {
 574                 sp = skb_sec_path(skb);
 575
 576                 if (sp->len == XFRM_MAX_DEPTH) {
 577                         secpath_reset(skb);
 578                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 579                         goto drop;
 580                 }
 581
 582                 x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
 583                 if (x == NULL) {
 584                         secpath_reset(skb);
 585                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
 586                         xfrm_audit_state_notfound(skb, family, spi, seq);
 587                         goto drop;
 588                 }
 589
 590                 skb->mark = xfrm_smark_get(skb->mark, x);
 591
 592                 sp->xvec[sp->len++] = x;
 593
 594                 skb_dst_force(skb);
 595                 if (!skb_dst(skb)) {
 596                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
 597                         goto drop;
 598                 }
 599
 600 lock:
 601                 spin_lock(&x->lock);
 602
 603                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
 604                         if (x->km.state == XFRM_STATE_ACQ)
 605                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
 606                         else
 607                                 XFRM_INC_STATS(net,
 608                                                LINUX_MIB_XFRMINSTATEINVALID);
 609                         goto drop_unlock;
 610                 }
 611
 612                 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
 613                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
 614                         goto drop_unlock;
 615                 }
 616
 617                 if (xfrm_replay_check(x, skb, seq)) {
 618                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 619                         goto drop_unlock;
 620                 }
 621
 622                 if (xfrm_state_check_expire(x)) {
 623                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
 624                         goto drop_unlock;
 625                 }
 626
 627                 spin_unlock(&x->lock);
 628
 629                 if (xfrm_tunnel_check(skb, x, family)) {
 630                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 631                         goto drop;
 632                 }
 633
 634                 seq_hi = htonl(xfrm_replay_seqhi(x, seq));
 635
 636                 XFRM_SKB_CB(skb)->seq.input.low = seq;
 637                 XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
 638
 639                 dev_hold(skb->dev);
 640
 641                 if (crypto_done)
 642                         nexthdr = x->type_offload->input_tail(x, skb);
 643                 else
 644                         nexthdr = x->type->input(x, skb);
 645
 646                 if (nexthdr == -EINPROGRESS)
 647                         return 0;
 648 resume:
 649                 dev_put(skb->dev);
 650
 651                 spin_lock(&x->lock);
 652                 if (nexthdr < 0) {
 653                         if (nexthdr == -EBADMSG) {
 654                                 xfrm_audit_state_icvfail(x, skb,
 655                                                          x->type->proto);
 656                                 x->stats.integrity_failed++;
 657                         }
 658                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 659                         goto drop_unlock;
 660                 }
 661
 662                 /* only the first xfrm gets the encap type */
 663                 encap_type = 0;
 664
 665                 if (xfrm_replay_recheck(x, skb, seq)) {
 666                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 667                         goto drop_unlock;
 668                 }
 669
 670                 xfrm_replay_advance(x, seq);
 671
 672                 x->curlft.bytes += skb->len;
 673                 x->curlft.packets++;
 674
 675                 spin_unlock(&x->lock);
 676
 677                 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
 678
 679                 inner_mode = &x->inner_mode;
 680
 681                 if (x->sel.family == AF_UNSPEC) {
 682                         inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
 683                         if (inner_mode == NULL) {
 684                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 685                                 goto drop;
 686                         }
 687                 }
 688
 689                 if (xfrm_inner_mode_input(x, inner_mode, skb)) {
 690                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 691                         goto drop;
 692                 }
 693
 694                 if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
 695                         decaps = 1;
 696                         break;
 697                 }
 698
 699                 /*
 700                  * We need the inner address.  However, we only get here for
 701                  * transport mode so the outer address is identical.
 702                  */
 703                 daddr = &x->id.daddr;
 704                 family = x->outer_mode.family;
 705
 706                 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
 707                 if (err < 0) {
 708                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 709                         goto drop;
 710                 }
 711                 crypto_done = false;
 712         } while (!err);
 713
 714         err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
 715         if (err)
 716                 goto drop;
 717
 718         nf_reset_ct(skb);
 719
 720         if (decaps) {
 721                 sp = skb_sec_path(skb);
 722                 if (sp)
 723                         sp->olen = 0;
 724                 if (skb_valid_dst(skb))
 725                         skb_dst_drop(skb);
 726                 gro_cells_receive(&gro_cells, skb);
 727                 return 0;
 728         } else {
 729                 xo = xfrm_offload(skb);
 730                 if (xo)
 731                         xfrm_gro = xo->flags & XFRM_GRO;
 732
 733                 err = -EAFNOSUPPORT;
 734                 rcu_read_lock();
 735                 afinfo = xfrm_state_afinfo_get_rcu(x->inner_mode.family);
 736                 if (likely(afinfo))
 737                         err = afinfo->transport_finish(skb, xfrm_gro || async);
 738                 rcu_read_unlock();
 739                 if (xfrm_gro) {
 740                         sp = skb_sec_path(skb);
 741                         if (sp)
 742                                 sp->olen = 0;
 743                         if (skb_valid_dst(skb))
 744                                 skb_dst_drop(skb);
 745                         gro_cells_receive(&gro_cells, skb);
 746                         return err;
 747                 }
 748
 749                 return err;
 750         }
 751
 752 drop_unlock:
 753         spin_unlock(&x->lock);
 754 drop:
 755         xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
 756         kfree_skb(skb);
 757         return 0;
 758 }
 759 EXPORT_SYMBOL(xfrm_input);
 760
 761 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
 762 {
 763         return xfrm_input(skb, nexthdr, 0, -1);
 764 }
 765 EXPORT_SYMBOL(xfrm_input_resume);
 766
 767 static void xfrm_trans_reinject(struct work_struct *work)
 768 {
 769         struct xfrm_trans_tasklet *trans = container_of(work, struct xfrm_trans_tasklet, work);
 770         struct sk_buff_head queue;
 771         struct sk_buff *skb;
 772
 773         __skb_queue_head_init(&queue);
 774         spin_lock_bh(&trans->queue_lock);
 775         skb_queue_splice_init(&trans->queue, &queue);
 776         spin_unlock_bh(&trans->queue_lock);
 777
 778         local_bh_disable();
 779         while ((skb = __skb_dequeue(&queue)))
 780                 XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
 781                                                NULL, skb);
 782         local_bh_enable();
 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         spin_lock_bh(&trans->queue_lock);
 801         __skb_queue_tail(&trans->queue, skb);
 802         spin_unlock_bh(&trans->queue_lock);
 803         schedule_work(&trans->work);
 804         return 0;
 805 }
 806 EXPORT_SYMBOL(xfrm_trans_queue_net);
 807
 808 int xfrm_trans_queue(struct sk_buff *skb,
 809                      int (*finish)(struct net *, struct sock *,
 810                                    struct sk_buff *))
 811 {
 812         return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
 813 }
 814 EXPORT_SYMBOL(xfrm_trans_queue);
 815
 816 void __init xfrm_input_init(void)
 817 {
 818         int err;
 819         int i;
 820
 821         init_dummy_netdev(&xfrm_napi_dev);
 822         err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
 823         if (err)
 824                 gro_cells.cells = NULL;
 825
 826         for_each_possible_cpu(i) {
 827                 struct xfrm_trans_tasklet *trans;
 828
 829                 trans = &per_cpu(xfrm_trans_tasklet, i);
 830                 spin_lock_init(&trans->queue_lock);
 831                 __skb_queue_head_init(&trans->queue);
 832                 INIT_WORK(&trans->work, xfrm_trans_reinject);
 833         }
 834 }