net/xfrm/xfrm_input.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * xfrm_input.c
   4  *
   5  * Changes:
   6  *      YOSHIFUJI Hideaki @USAGI
   7  *              Split up af-specific portion
   8  *
   9  */
  10
  11 #include <linux/bottom_half.h>
  12 #include <linux/cache.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/slab.h>
  15 #include <linux/module.h>
  16 #include <linux/netdevice.h>
  17 #include <linux/percpu.h>
  18 #include <net/dst.h>
  19 #include <net/ip.h>
  20 #include <net/xfrm.h>
  21 #include <net/ip_tunnels.h>
  22 #include <net/ip6_tunnel.h>
  23
  24 #include "xfrm_inout.h"
  25
  26 struct xfrm_trans_tasklet {
  27         struct tasklet_struct tasklet;
  28         struct sk_buff_head queue;
  29 };
  30
  31 struct xfrm_trans_cb {
  32         union {
  33                 struct inet_skb_parm    h4;
  34 #if IS_ENABLED(CONFIG_IPV6)
  35                 struct inet6_skb_parm   h6;
  36 #endif
  37         } header;
  38         int (*finish)(struct net *net, struct sock *sk, struct sk_buff *skb);
  39         struct net *net;
  40 };
  41
  42 #define XFRM_TRANS_SKB_CB(__skb) ((struct xfrm_trans_cb *)&((__skb)->cb[0]))
  43
  44 static DEFINE_SPINLOCK(xfrm_input_afinfo_lock);
  45 static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[AF_INET6 + 1];
  46
  47 static struct gro_cells gro_cells;
  48 static struct net_device xfrm_napi_dev;
  49
  50 static DEFINE_PER_CPU(struct xfrm_trans_tasklet, xfrm_trans_tasklet);
  51
  52 int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo)
  53 {
  54         int err = 0;
  55
  56         if (WARN_ON(afinfo->family >= ARRAY_SIZE(xfrm_input_afinfo)))
  57                 return -EAFNOSUPPORT;
  58
  59         spin_lock_bh(&xfrm_input_afinfo_lock);
  60         if (unlikely(xfrm_input_afinfo[afinfo->family] != NULL))
  61                 err = -EEXIST;
  62         else
  63                 rcu_assign_pointer(xfrm_input_afinfo[afinfo->family], afinfo);
  64         spin_unlock_bh(&xfrm_input_afinfo_lock);
  65         return err;
  66 }
  67 EXPORT_SYMBOL(xfrm_input_register_afinfo);
  68
  69 int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo)
  70 {
  71         int err = 0;
  72
  73         spin_lock_bh(&xfrm_input_afinfo_lock);
  74         if (likely(xfrm_input_afinfo[afinfo->family] != NULL)) {
  75                 if (unlikely(xfrm_input_afinfo[afinfo->family] != afinfo))
  76                         err = -EINVAL;
  77                 else
  78                         RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->family], NULL);
  79         }
  80         spin_unlock_bh(&xfrm_input_afinfo_lock);
  81         synchronize_rcu();
  82         return err;
  83 }
  84 EXPORT_SYMBOL(xfrm_input_unregister_afinfo);
  85
  86 static const struct xfrm_input_afinfo *xfrm_input_get_afinfo(unsigned int family)
  87 {
  88         const struct xfrm_input_afinfo *afinfo;
  89
  90         if (WARN_ON_ONCE(family >= ARRAY_SIZE(xfrm_input_afinfo)))
  91                 return NULL;
  92
  93         rcu_read_lock();
  94         afinfo = rcu_dereference(xfrm_input_afinfo[family]);
  95         if (unlikely(!afinfo))
  96                 rcu_read_unlock();
  97         return afinfo;
  98 }
  99
 100 static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
 101                        int err)
 102 {
 103         int ret;
 104         const struct xfrm_input_afinfo *afinfo = xfrm_input_get_afinfo(family);
 105
 106         if (!afinfo)
 107                 return -EAFNOSUPPORT;
 108
 109         ret = afinfo->callback(skb, protocol, err);
 110         rcu_read_unlock();
 111
 112         return ret;
 113 }
 114
 115 struct sec_path *secpath_set(struct sk_buff *skb)
 116 {
 117         struct sec_path *sp, *tmp = skb_ext_find(skb, SKB_EXT_SEC_PATH);
 118
 119         sp = skb_ext_add(skb, SKB_EXT_SEC_PATH);
 120         if (!sp)
 121                 return NULL;
 122
 123         if (tmp) /* reused existing one (was COW'd if needed) */
 124                 return sp;
 125
 126         /* allocated new secpath */
 127         memset(sp->ovec, 0, sizeof(sp->ovec));
 128         sp->olen = 0;
 129         sp->len = 0;
 130
 131         return sp;
 132 }
 133 EXPORT_SYMBOL(secpath_set);
 134
 135 /* Fetch spi and seq from ipsec header */
 136
 137 int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
 138 {
 139         int offset, offset_seq;
 140         int hlen;
 141
 142         switch (nexthdr) {
 143         case IPPROTO_AH:
 144                 hlen = sizeof(struct ip_auth_hdr);
 145                 offset = offsetof(struct ip_auth_hdr, spi);
 146                 offset_seq = offsetof(struct ip_auth_hdr, seq_no);
 147                 break;
 148         case IPPROTO_ESP:
 149                 hlen = sizeof(struct ip_esp_hdr);
 150                 offset = offsetof(struct ip_esp_hdr, spi);
 151                 offset_seq = offsetof(struct ip_esp_hdr, seq_no);
 152                 break;
 153         case IPPROTO_COMP:
 154                 if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr)))
 155                         return -EINVAL;
 156                 *spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2)));
 157                 *seq = 0;
 158                 return 0;
 159         default:
 160                 return 1;
 161         }
 162
 163         if (!pskb_may_pull(skb, hlen))
 164                 return -EINVAL;
 165
 166         *spi = *(__be32 *)(skb_transport_header(skb) + offset);
 167         *seq = *(__be32 *)(skb_transport_header(skb) + offset_seq);
 168         return 0;
 169 }
 170 EXPORT_SYMBOL(xfrm_parse_spi);
 171
 172 static int xfrm4_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
 173 {
 174         struct iphdr *iph;
 175         int optlen = 0;
 176         int err = -EINVAL;
 177
 178         if (unlikely(XFRM_MODE_SKB_CB(skb)->protocol == IPPROTO_BEETPH)) {
 179                 struct ip_beet_phdr *ph;
 180                 int phlen;
 181
 182                 if (!pskb_may_pull(skb, sizeof(*ph)))
 183                         goto out;
 184
 185                 ph = (struct ip_beet_phdr *)skb->data;
 186
 187                 phlen = sizeof(*ph) + ph->padlen;
 188                 optlen = ph->hdrlen * 8 + (IPV4_BEET_PHMAXLEN - phlen);
 189                 if (optlen < 0 || optlen & 3 || optlen > 250)
 190                         goto out;
 191
 192                 XFRM_MODE_SKB_CB(skb)->protocol = ph->nexthdr;
 193
 194                 if (!pskb_may_pull(skb, phlen))
 195                         goto out;
 196                 __skb_pull(skb, phlen);
 197         }
 198
 199         skb_push(skb, sizeof(*iph));
 200         skb_reset_network_header(skb);
 201         skb_mac_header_rebuild(skb);
 202
 203         xfrm4_beet_make_header(skb);
 204
 205         iph = ip_hdr(skb);
 206
 207         iph->ihl += optlen / 4;
 208         iph->tot_len = htons(skb->len);
 209         iph->daddr = x->sel.daddr.a4;
 210         iph->saddr = x->sel.saddr.a4;
 211         iph->check = 0;
 212         iph->check = ip_fast_csum(skb_network_header(skb), iph->ihl);
 213         err = 0;
 214 out:
 215         return err;
 216 }
 217
 218 static void ipip_ecn_decapsulate(struct sk_buff *skb)
 219 {
 220         struct iphdr *inner_iph = ipip_hdr(skb);
 221
 222         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
 223                 IP_ECN_set_ce(inner_iph);
 224 }
 225
 226 static int xfrm4_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 227 {
 228         int err = -EINVAL;
 229
 230         if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
 231                 goto out;
 232
 233         if (!pskb_may_pull(skb, sizeof(struct iphdr)))
 234                 goto out;
 235
 236         err = skb_unclone(skb, GFP_ATOMIC);
 237         if (err)
 238                 goto out;
 239
 240         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
 241                 ipv4_copy_dscp(XFRM_MODE_SKB_CB(skb)->tos, ipip_hdr(skb));
 242         if (!(x->props.flags & XFRM_STATE_NOECN))
 243                 ipip_ecn_decapsulate(skb);
 244
 245         skb_reset_network_header(skb);
 246         skb_mac_header_rebuild(skb);
 247         if (skb->mac_len)
 248                 eth_hdr(skb)->h_proto = skb->protocol;
 249
 250         err = 0;
 251
 252 out:
 253         return err;
 254 }
 255
 256 static void ipip6_ecn_decapsulate(struct sk_buff *skb)
 257 {
 258         struct ipv6hdr *inner_iph = ipipv6_hdr(skb);
 259
 260         if (INET_ECN_is_ce(XFRM_MODE_SKB_CB(skb)->tos))
 261                 IP6_ECN_set_ce(skb, inner_iph);
 262 }
 263
 264 static int xfrm6_remove_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 265 {
 266         int err = -EINVAL;
 267
 268         if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
 269                 goto out;
 270         if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
 271                 goto out;
 272
 273         err = skb_unclone(skb, GFP_ATOMIC);
 274         if (err)
 275                 goto out;
 276
 277         if (x->props.flags & XFRM_STATE_DECAP_DSCP)
 278                 ipv6_copy_dscp(ipv6_get_dsfield(ipv6_hdr(skb)),
 279                                ipipv6_hdr(skb));
 280         if (!(x->props.flags & XFRM_STATE_NOECN))
 281                 ipip6_ecn_decapsulate(skb);
 282
 283         skb_reset_network_header(skb);
 284         skb_mac_header_rebuild(skb);
 285         if (skb->mac_len)
 286                 eth_hdr(skb)->h_proto = skb->protocol;
 287
 288         err = 0;
 289
 290 out:
 291         return err;
 292 }
 293
 294 static int xfrm6_remove_beet_encap(struct xfrm_state *x, struct sk_buff *skb)
 295 {
 296         struct ipv6hdr *ip6h;
 297         int size = sizeof(struct ipv6hdr);
 298         int err;
 299
 300         err = skb_cow_head(skb, size + skb->mac_len);
 301         if (err)
 302                 goto out;
 303
 304         __skb_push(skb, size);
 305         skb_reset_network_header(skb);
 306         skb_mac_header_rebuild(skb);
 307
 308         xfrm6_beet_make_header(skb);
 309
 310         ip6h = ipv6_hdr(skb);
 311         ip6h->payload_len = htons(skb->len - size);
 312         ip6h->daddr = x->sel.daddr.in6;
 313         ip6h->saddr = x->sel.saddr.in6;
 314         err = 0;
 315 out:
 316         return err;
 317 }
 318
 319 /* Remove encapsulation header.
 320  *
 321  * The IP header will be moved over the top of the encapsulation
 322  * header.
 323  *
 324  * On entry, the transport header shall point to where the IP header
 325  * should be and the network header shall be set to where the IP
 326  * header currently is.  skb->data shall point to the start of the
 327  * payload.
 328  */
 329 static int
 330 xfrm_inner_mode_encap_remove(struct xfrm_state *x,
 331                              const struct xfrm_mode *inner_mode,
 332                              struct sk_buff *skb)
 333 {
 334         switch (inner_mode->encap) {
 335         case XFRM_MODE_BEET:
 336                 if (inner_mode->family == AF_INET)
 337                         return xfrm4_remove_beet_encap(x, skb);
 338                 if (inner_mode->family == AF_INET6)
 339                         return xfrm6_remove_beet_encap(x, skb);
 340                 break;
 341         case XFRM_MODE_TUNNEL:
 342                 if (inner_mode->family == AF_INET)
 343                         return xfrm4_remove_tunnel_encap(x, skb);
 344                 if (inner_mode->family == AF_INET6)
 345                         return xfrm6_remove_tunnel_encap(x, skb);
 346                 break;
 347         }
 348
 349         WARN_ON_ONCE(1);
 350         return -EOPNOTSUPP;
 351 }
 352
 353 static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 354 {
 355         const struct xfrm_mode *inner_mode = &x->inner_mode;
 356         const struct xfrm_state_afinfo *afinfo;
 357         int err = -EAFNOSUPPORT;
 358
 359         rcu_read_lock();
 360         afinfo = xfrm_state_afinfo_get_rcu(x->outer_mode.family);
 361         if (likely(afinfo))
 362                 err = afinfo->extract_input(x, skb);
 363         rcu_read_unlock();
 364
 365         if (err)
 366                 return err;
 367
 368         if (x->sel.family == AF_UNSPEC) {
 369                 inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
 370                 if (!inner_mode)
 371                         return -EAFNOSUPPORT;
 372         }
 373
 374         switch (inner_mode->family) {
 375         case AF_INET:
 376                 skb->protocol = htons(ETH_P_IP);
 377                 break;
 378         case AF_INET6:
 379                 skb->protocol = htons(ETH_P_IPV6);
 380                 break;
 381         default:
 382                 WARN_ON_ONCE(1);
 383                 break;
 384         }
 385
 386         return xfrm_inner_mode_encap_remove(x, inner_mode, skb);
 387 }
 388
 389 /* Remove encapsulation header.
 390  *
 391  * The IP header will be moved over the top of the encapsulation header.
 392  *
 393  * On entry, skb_transport_header() shall point to where the IP header
 394  * should be and skb_network_header() shall be set to where the IP header
 395  * currently is.  skb->data shall point to the start of the payload.
 396  */
 397 static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 398 {
 399         int ihl = skb->data - skb_transport_header(skb);
 400
 401         if (skb->transport_header != skb->network_header) {
 402                 memmove(skb_transport_header(skb),
 403                         skb_network_header(skb), ihl);
 404                 skb->network_header = skb->transport_header;
 405         }
 406         ip_hdr(skb)->tot_len = htons(skb->len + ihl);
 407         skb_reset_transport_header(skb);
 408         return 0;
 409 }
 410
 411 static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
 412 {
 413 #if IS_ENABLED(CONFIG_IPV6)
 414         int ihl = skb->data - skb_transport_header(skb);
 415
 416         if (skb->transport_header != skb->network_header) {
 417                 memmove(skb_transport_header(skb),
 418                         skb_network_header(skb), ihl);
 419                 skb->network_header = skb->transport_header;
 420         }
 421         ipv6_hdr(skb)->payload_len = htons(skb->len + ihl -
 422                                            sizeof(struct ipv6hdr));
 423         skb_reset_transport_header(skb);
 424         return 0;
 425 #else
 426         WARN_ON_ONCE(1);
 427         return -EAFNOSUPPORT;
 428 #endif
 429 }
 430
 431 static int xfrm_inner_mode_input(struct xfrm_state *x,
 432                                  const struct xfrm_mode *inner_mode,
 433                                  struct sk_buff *skb)
 434 {
 435         switch (inner_mode->encap) {
 436         case XFRM_MODE_BEET:
 437         case XFRM_MODE_TUNNEL:
 438                 return xfrm_prepare_input(x, skb);
 439         case XFRM_MODE_TRANSPORT:
 440                 if (inner_mode->family == AF_INET)
 441                         return xfrm4_transport_input(x, skb);
 442                 if (inner_mode->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         const struct xfrm_mode *inner_mode;
 461         int err;
 462         __be32 seq;
 463         __be32 seq_hi;
 464         struct xfrm_state *x = NULL;
 465         xfrm_address_t *daddr;
 466         u32 mark = skb->mark;
 467         unsigned int family = AF_UNSPEC;
 468         int decaps = 0;
 469         int async = 0;
 470         bool xfrm_gro = false;
 471         bool crypto_done = false;
 472         struct xfrm_offload *xo = xfrm_offload(skb);
 473         struct sec_path *sp;
 474
 475         if (encap_type < 0) {
 476                 x = xfrm_input_state(skb);
 477
 478                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
 479                         if (x->km.state == XFRM_STATE_ACQ)
 480                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
 481                         else
 482                                 XFRM_INC_STATS(net,
 483                                                LINUX_MIB_XFRMINSTATEINVALID);
 484
 485                         if (encap_type == -1)
 486                                 dev_put(skb->dev);
 487                         goto drop;
 488                 }
 489
 490                 family = x->outer_mode.family;
 491
 492                 /* An encap_type of -1 indicates async resumption. */
 493                 if (encap_type == -1) {
 494                         async = 1;
 495                         seq = XFRM_SKB_CB(skb)->seq.input.low;
 496                         goto resume;
 497                 }
 498
 499                 /* encap_type < -1 indicates a GRO call. */
 500                 encap_type = 0;
 501                 seq = XFRM_SPI_SKB_CB(skb)->seq;
 502
 503                 if (xo && (xo->flags & CRYPTO_DONE)) {
 504                         crypto_done = true;
 505                         family = XFRM_SPI_SKB_CB(skb)->family;
 506
 507                         if (!(xo->status & CRYPTO_SUCCESS)) {
 508                                 if (xo->status &
 509                                     (CRYPTO_TRANSPORT_AH_AUTH_FAILED |
 510                                      CRYPTO_TRANSPORT_ESP_AUTH_FAILED |
 511                                      CRYPTO_TUNNEL_AH_AUTH_FAILED |
 512                                      CRYPTO_TUNNEL_ESP_AUTH_FAILED)) {
 513
 514                                         xfrm_audit_state_icvfail(x, skb,
 515                                                                  x->type->proto);
 516                                         x->stats.integrity_failed++;
 517                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 518                                         goto drop;
 519                                 }
 520
 521                                 if (xo->status & CRYPTO_INVALID_PROTOCOL) {
 522                                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 523                                         goto drop;
 524                                 }
 525
 526                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 527                                 goto drop;
 528                         }
 529
 530                         if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
 531                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 532                                 goto drop;
 533                         }
 534                 }
 535
 536                 goto lock;
 537         }
 538
 539         family = XFRM_SPI_SKB_CB(skb)->family;
 540
 541         /* if tunnel is present override skb->mark value with tunnel i_key */
 542         switch (family) {
 543         case AF_INET:
 544                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4)
 545                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
 546                 break;
 547         case AF_INET6:
 548                 if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6)
 549                         mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key);
 550                 break;
 551         }
 552
 553         sp = secpath_set(skb);
 554         if (!sp) {
 555                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
 556                 goto drop;
 557         }
 558
 559         seq = 0;
 560         if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) {
 561                 secpath_reset(skb);
 562                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 563                 goto drop;
 564         }
 565
 566         daddr = (xfrm_address_t *)(skb_network_header(skb) +
 567                                    XFRM_SPI_SKB_CB(skb)->daddroff);
 568         do {
 569                 sp = skb_sec_path(skb);
 570
 571                 if (sp->len == XFRM_MAX_DEPTH) {
 572                         secpath_reset(skb);
 573                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
 574                         goto drop;
 575                 }
 576
 577                 x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family);
 578                 if (x == NULL) {
 579                         secpath_reset(skb);
 580                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
 581                         xfrm_audit_state_notfound(skb, family, spi, seq);
 582                         goto drop;
 583                 }
 584
 585                 skb->mark = xfrm_smark_get(skb->mark, x);
 586
 587                 sp->xvec[sp->len++] = x;
 588
 589                 skb_dst_force(skb);
 590                 if (!skb_dst(skb)) {
 591                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
 592                         goto drop;
 593                 }
 594
 595 lock:
 596                 spin_lock(&x->lock);
 597
 598                 if (unlikely(x->km.state != XFRM_STATE_VALID)) {
 599                         if (x->km.state == XFRM_STATE_ACQ)
 600                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
 601                         else
 602                                 XFRM_INC_STATS(net,
 603                                                LINUX_MIB_XFRMINSTATEINVALID);
 604                         goto drop_unlock;
 605                 }
 606
 607                 if ((x->encap ? x->encap->encap_type : 0) != encap_type) {
 608                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH);
 609                         goto drop_unlock;
 610                 }
 611
 612                 if (x->repl->check(x, skb, seq)) {
 613                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 614                         goto drop_unlock;
 615                 }
 616
 617                 if (xfrm_state_check_expire(x)) {
 618                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED);
 619                         goto drop_unlock;
 620                 }
 621
 622                 spin_unlock(&x->lock);
 623
 624                 if (xfrm_tunnel_check(skb, x, family)) {
 625                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 626                         goto drop;
 627                 }
 628
 629                 seq_hi = htonl(xfrm_replay_seqhi(x, seq));
 630
 631                 XFRM_SKB_CB(skb)->seq.input.low = seq;
 632                 XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
 633
 634                 dev_hold(skb->dev);
 635
 636                 if (crypto_done)
 637                         nexthdr = x->type_offload->input_tail(x, skb);
 638                 else
 639                         nexthdr = x->type->input(x, skb);
 640
 641                 if (nexthdr == -EINPROGRESS)
 642                         return 0;
 643 resume:
 644                 dev_put(skb->dev);
 645
 646                 spin_lock(&x->lock);
 647                 if (nexthdr <= 0) {
 648                         if (nexthdr == -EBADMSG) {
 649                                 xfrm_audit_state_icvfail(x, skb,
 650                                                          x->type->proto);
 651                                 x->stats.integrity_failed++;
 652                         }
 653                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR);
 654                         goto drop_unlock;
 655                 }
 656
 657                 /* only the first xfrm gets the encap type */
 658                 encap_type = 0;
 659
 660                 if (async && x->repl->recheck(x, skb, seq)) {
 661                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR);
 662                         goto drop_unlock;
 663                 }
 664
 665                 x->repl->advance(x, seq);
 666
 667                 x->curlft.bytes += skb->len;
 668                 x->curlft.packets++;
 669
 670                 spin_unlock(&x->lock);
 671
 672                 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
 673
 674                 inner_mode = &x->inner_mode;
 675
 676                 if (x->sel.family == AF_UNSPEC) {
 677                         inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
 678                         if (inner_mode == NULL) {
 679                                 XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 680                                 goto drop;
 681                         }
 682                 }
 683
 684                 if (xfrm_inner_mode_input(x, inner_mode, skb)) {
 685                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR);
 686                         goto drop;
 687                 }
 688
 689                 if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
 690                         decaps = 1;
 691                         break;
 692                 }
 693
 694                 /*
 695                  * We need the inner address.  However, we only get here for
 696                  * transport mode so the outer address is identical.
 697                  */
 698                 daddr = &x->id.daddr;
 699                 family = x->outer_mode.family;
 700
 701                 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
 702                 if (err < 0) {
 703                         XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR);
 704                         goto drop;
 705                 }
 706                 crypto_done = false;
 707         } while (!err);
 708
 709         err = xfrm_rcv_cb(skb, family, x->type->proto, 0);
 710         if (err)
 711                 goto drop;
 712
 713         nf_reset_ct(skb);
 714
 715         if (decaps) {
 716                 sp = skb_sec_path(skb);
 717                 if (sp)
 718                         sp->olen = 0;
 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->inner_mode.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                         skb_dst_drop(skb);
 738                         gro_cells_receive(&gro_cells, skb);
 739                         return err;
 740                 }
 741
 742                 return err;
 743         }
 744
 745 drop_unlock:
 746         spin_unlock(&x->lock);
 747 drop:
 748         xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1);
 749         kfree_skb(skb);
 750         return 0;
 751 }
 752 EXPORT_SYMBOL(xfrm_input);
 753
 754 int xfrm_input_resume(struct sk_buff *skb, int nexthdr)
 755 {
 756         return xfrm_input(skb, nexthdr, 0, -1);
 757 }
 758 EXPORT_SYMBOL(xfrm_input_resume);
 759
 760 static void xfrm_trans_reinject(unsigned long data)
 761 {
 762         struct xfrm_trans_tasklet *trans = (void *)data;
 763         struct sk_buff_head queue;
 764         struct sk_buff *skb;
 765
 766         __skb_queue_head_init(&queue);
 767         skb_queue_splice_init(&trans->queue, &queue);
 768
 769         while ((skb = __skb_dequeue(&queue)))
 770                 XFRM_TRANS_SKB_CB(skb)->finish(XFRM_TRANS_SKB_CB(skb)->net,
 771                                                NULL, skb);
 772 }
 773
 774 int xfrm_trans_queue_net(struct net *net, struct sk_buff *skb,
 775                          int (*finish)(struct net *, struct sock *,
 776                                        struct sk_buff *))
 777 {
 778         struct xfrm_trans_tasklet *trans;
 779
 780         trans = this_cpu_ptr(&xfrm_trans_tasklet);
 781
 782         if (skb_queue_len(&trans->queue) >= netdev_max_backlog)
 783                 return -ENOBUFS;
 784
 785         BUILD_BUG_ON(sizeof(struct xfrm_trans_cb) > sizeof(skb->cb));
 786
 787         XFRM_TRANS_SKB_CB(skb)->finish = finish;
 788         XFRM_TRANS_SKB_CB(skb)->net = net;
 789         __skb_queue_tail(&trans->queue, skb);
 790         tasklet_schedule(&trans->tasklet);
 791         return 0;
 792 }
 793 EXPORT_SYMBOL(xfrm_trans_queue_net);
 794
 795 int xfrm_trans_queue(struct sk_buff *skb,
 796                      int (*finish)(struct net *, struct sock *,
 797                                    struct sk_buff *))
 798 {
 799         return xfrm_trans_queue_net(dev_net(skb->dev), skb, finish);
 800 }
 801 EXPORT_SYMBOL(xfrm_trans_queue);
 802
 803 void __init xfrm_input_init(void)
 804 {
 805         int err;
 806         int i;
 807
 808         init_dummy_netdev(&xfrm_napi_dev);
 809         err = gro_cells_init(&gro_cells, &xfrm_napi_dev);
 810         if (err)
 811                 gro_cells.cells = NULL;
 812
 813         for_each_possible_cpu(i) {
 814                 struct xfrm_trans_tasklet *trans;
 815
 816                 trans = &per_cpu(xfrm_trans_tasklet, i);
 817                 __skb_queue_head_init(&trans->queue);
 818                 tasklet_init(&trans->tasklet, xfrm_trans_reinject,
 819                              (unsigned long)trans);
 820         }
 821 }