net/core/flow_dissector.c

   1 #include <linux/kernel.h>
   2 #include <linux/skbuff.h>
   3 #include <linux/export.h>
   4 #include <linux/ip.h>
   5 #include <linux/ipv6.h>
   6 #include <linux/if_vlan.h>
   7 #include <net/ip.h>
   8 #include <net/ipv6.h>
   9 #include <net/gre.h>
  10 #include <net/pptp.h>
  11 #include <linux/igmp.h>
  12 #include <linux/icmp.h>
  13 #include <linux/sctp.h>
  14 #include <linux/dccp.h>
  15 #include <linux/if_tunnel.h>
  16 #include <linux/if_pppox.h>
  17 #include <linux/ppp_defs.h>
  18 #include <linux/stddef.h>
  19 #include <linux/if_ether.h>
  20 #include <linux/mpls.h>
  21 #include <net/flow_dissector.h>
  22 #include <scsi/fc/fc_fcoe.h>
  23
  24 static void dissector_set_key(struct flow_dissector *flow_dissector,
  25                               enum flow_dissector_key_id key_id)
  26 {
  27         flow_dissector->used_keys |= (1 << key_id);
  28 }
  29
  30 void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
  31                              const struct flow_dissector_key *key,
  32                              unsigned int key_count)
  33 {
  34         unsigned int i;
  35
  36         memset(flow_dissector, 0, sizeof(*flow_dissector));
  37
  38         for (i = 0; i < key_count; i++, key++) {
  39                 /* User should make sure that every key target offset is withing
  40                  * boundaries of unsigned short.
  41                  */
  42                 BUG_ON(key->offset > USHRT_MAX);
  43                 BUG_ON(dissector_uses_key(flow_dissector,
  44                                           key->key_id));
  45
  46                 dissector_set_key(flow_dissector, key->key_id);
  47                 flow_dissector->offset[key->key_id] = key->offset;
  48         }
  49
  50         /* Ensure that the dissector always includes control and basic key.
  51          * That way we are able to avoid handling lack of these in fast path.
  52          */
  53         BUG_ON(!dissector_uses_key(flow_dissector,
  54                                    FLOW_DISSECTOR_KEY_CONTROL));
  55         BUG_ON(!dissector_uses_key(flow_dissector,
  56                                    FLOW_DISSECTOR_KEY_BASIC));
  57 }
  58 EXPORT_SYMBOL(skb_flow_dissector_init);
  59
  60 /**
  61  * skb_flow_get_be16 - extract be16 entity
  62  * @skb: sk_buff to extract from
  63  * @poff: offset to extract at
  64  * @data: raw buffer pointer to the packet
  65  * @hlen: packet header length
  66  *
  67  * The function will try to retrieve a be32 entity at
  68  * offset poff
  69  */
  70 static __be16 skb_flow_get_be16(const struct sk_buff *skb, int poff,
  71                                 void *data, int hlen)
  72 {
  73         __be16 *u, _u;
  74
  75         u = __skb_header_pointer(skb, poff, sizeof(_u), data, hlen, &_u);
  76         if (u)
  77                 return *u;
  78
  79         return 0;
  80 }
  81
  82 /**
  83  * __skb_flow_get_ports - extract the upper layer ports and return them
  84  * @skb: sk_buff to extract the ports from
  85  * @thoff: transport header offset
  86  * @ip_proto: protocol for which to get port offset
  87  * @data: raw buffer pointer to the packet, if NULL use skb->data
  88  * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
  89  *
  90  * The function will try to retrieve the ports at offset thoff + poff where poff
  91  * is the protocol port offset returned from proto_ports_offset
  92  */
  93 __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
  94                             void *data, int hlen)
  95 {
  96         int poff = proto_ports_offset(ip_proto);
  97
  98         if (!data) {
  99                 data = skb->data;
 100                 hlen = skb_headlen(skb);
 101         }
 102
 103         if (poff >= 0) {
 104                 __be32 *ports, _ports;
 105
 106                 ports = __skb_header_pointer(skb, thoff + poff,
 107                                              sizeof(_ports), data, hlen, &_ports);
 108                 if (ports)
 109                         return *ports;
 110         }
 111
 112         return 0;
 113 }
 114 EXPORT_SYMBOL(__skb_flow_get_ports);
 115
 116 enum flow_dissect_ret {
 117         FLOW_DISSECT_RET_OUT_GOOD,
 118         FLOW_DISSECT_RET_OUT_BAD,
 119         FLOW_DISSECT_RET_OUT_PROTO_AGAIN,
 120 };
 121
 122 static enum flow_dissect_ret
 123 __skb_flow_dissect_mpls(const struct sk_buff *skb,
 124                         struct flow_dissector *flow_dissector,
 125                         void *target_container, void *data, int nhoff, int hlen)
 126 {
 127         struct flow_dissector_key_keyid *key_keyid;
 128         struct mpls_label *hdr, _hdr[2];
 129         u32 entry, label;
 130
 131         if (!dissector_uses_key(flow_dissector,
 132                                 FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
 133             !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
 134                 return FLOW_DISSECT_RET_OUT_GOOD;
 135
 136         hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
 137                                    hlen, &_hdr);
 138         if (!hdr)
 139                 return FLOW_DISSECT_RET_OUT_BAD;
 140
 141         entry = ntohl(hdr[0].entry);
 142         label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
 143
 144         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
 145                 struct flow_dissector_key_mpls *key_mpls;
 146
 147                 key_mpls = skb_flow_dissector_target(flow_dissector,
 148                                                      FLOW_DISSECTOR_KEY_MPLS,
 149                                                      target_container);
 150                 key_mpls->mpls_label = label;
 151                 key_mpls->mpls_ttl = (entry & MPLS_LS_TTL_MASK)
 152                                         >> MPLS_LS_TTL_SHIFT;
 153                 key_mpls->mpls_tc = (entry & MPLS_LS_TC_MASK)
 154                                         >> MPLS_LS_TC_SHIFT;
 155                 key_mpls->mpls_bos = (entry & MPLS_LS_S_MASK)
 156                                         >> MPLS_LS_S_SHIFT;
 157         }
 158
 159         if (label == MPLS_LABEL_ENTROPY) {
 160                 key_keyid = skb_flow_dissector_target(flow_dissector,
 161                                                       FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
 162                                                       target_container);
 163                 key_keyid->keyid = hdr[1].entry & htonl(MPLS_LS_LABEL_MASK);
 164         }
 165         return FLOW_DISSECT_RET_OUT_GOOD;
 166 }
 167
 168 static enum flow_dissect_ret
 169 __skb_flow_dissect_arp(const struct sk_buff *skb,
 170                        struct flow_dissector *flow_dissector,
 171                        void *target_container, void *data, int nhoff, int hlen)
 172 {
 173         struct flow_dissector_key_arp *key_arp;
 174         struct {
 175                 unsigned char ar_sha[ETH_ALEN];
 176                 unsigned char ar_sip[4];
 177                 unsigned char ar_tha[ETH_ALEN];
 178                 unsigned char ar_tip[4];
 179         } *arp_eth, _arp_eth;
 180         const struct arphdr *arp;
 181         struct arphdr _arp;
 182
 183         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
 184                 return FLOW_DISSECT_RET_OUT_GOOD;
 185
 186         arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
 187                                    hlen, &_arp);
 188         if (!arp)
 189                 return FLOW_DISSECT_RET_OUT_BAD;
 190
 191         if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
 192             arp->ar_pro != htons(ETH_P_IP) ||
 193             arp->ar_hln != ETH_ALEN ||
 194             arp->ar_pln != 4 ||
 195             (arp->ar_op != htons(ARPOP_REPLY) &&
 196              arp->ar_op != htons(ARPOP_REQUEST)))
 197                 return FLOW_DISSECT_RET_OUT_BAD;
 198
 199         arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
 200                                        sizeof(_arp_eth), data,
 201                                        hlen, &_arp_eth);
 202         if (!arp_eth)
 203                 return FLOW_DISSECT_RET_OUT_BAD;
 204
 205         key_arp = skb_flow_dissector_target(flow_dissector,
 206                                             FLOW_DISSECTOR_KEY_ARP,
 207                                             target_container);
 208
 209         memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
 210         memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));
 211
 212         /* Only store the lower byte of the opcode;
 213          * this covers ARPOP_REPLY and ARPOP_REQUEST.
 214          */
 215         key_arp->op = ntohs(arp->ar_op) & 0xff;
 216
 217         ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
 218         ether_addr_copy(key_arp->tha, arp_eth->ar_tha);
 219
 220         return FLOW_DISSECT_RET_OUT_GOOD;
 221 }
 222
 223 static enum flow_dissect_ret
 224 __skb_flow_dissect_gre(const struct sk_buff *skb,
 225                        struct flow_dissector_key_control *key_control,
 226                        struct flow_dissector *flow_dissector,
 227                        void *target_container, void *data,
 228                        __be16 *p_proto, int *p_nhoff, int *p_hlen,
 229                        unsigned int flags)
 230 {
 231         struct flow_dissector_key_keyid *key_keyid;
 232         struct gre_base_hdr *hdr, _hdr;
 233         int offset = 0;
 234         u16 gre_ver;
 235
 236         hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr),
 237                                    data, *p_hlen, &_hdr);
 238         if (!hdr)
 239                 return FLOW_DISSECT_RET_OUT_BAD;
 240
 241         /* Only look inside GRE without routing */
 242         if (hdr->flags & GRE_ROUTING)
 243                 return FLOW_DISSECT_RET_OUT_GOOD;
 244
 245         /* Only look inside GRE for version 0 and 1 */
 246         gre_ver = ntohs(hdr->flags & GRE_VERSION);
 247         if (gre_ver > 1)
 248                 return FLOW_DISSECT_RET_OUT_GOOD;
 249
 250         *p_proto = hdr->protocol;
 251         if (gre_ver) {
 252                 /* Version1 must be PPTP, and check the flags */
 253                 if (!(*p_proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
 254                         return FLOW_DISSECT_RET_OUT_GOOD;
 255         }
 256
 257         offset += sizeof(struct gre_base_hdr);
 258
 259         if (hdr->flags & GRE_CSUM)
 260                 offset += sizeof(((struct gre_full_hdr *) 0)->csum) +
 261                           sizeof(((struct gre_full_hdr *) 0)->reserved1);
 262
 263         if (hdr->flags & GRE_KEY) {
 264                 const __be32 *keyid;
 265                 __be32 _keyid;
 266
 267                 keyid = __skb_header_pointer(skb, *p_nhoff + offset,
 268                                              sizeof(_keyid),
 269                                              data, *p_hlen, &_keyid);
 270                 if (!keyid)
 271                         return FLOW_DISSECT_RET_OUT_BAD;
 272
 273                 if (dissector_uses_key(flow_dissector,
 274                                        FLOW_DISSECTOR_KEY_GRE_KEYID)) {
 275                         key_keyid = skb_flow_dissector_target(flow_dissector,
 276                                                               FLOW_DISSECTOR_KEY_GRE_KEYID,
 277                                                               target_container);
 278                         if (gre_ver == 0)
 279                                 key_keyid->keyid = *keyid;
 280                         else
 281                                 key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
 282                 }
 283                 offset += sizeof(((struct gre_full_hdr *) 0)->key);
 284         }
 285
 286         if (hdr->flags & GRE_SEQ)
 287                 offset += sizeof(((struct pptp_gre_header *) 0)->seq);
 288
 289         if (gre_ver == 0) {
 290                 if (*p_proto == htons(ETH_P_TEB)) {
 291                         const struct ethhdr *eth;
 292                         struct ethhdr _eth;
 293
 294                         eth = __skb_header_pointer(skb, *p_nhoff + offset,
 295                                                    sizeof(_eth),
 296                                                    data, *p_hlen, &_eth);
 297                         if (!eth)
 298                                 return FLOW_DISSECT_RET_OUT_BAD;
 299                         *p_proto = eth->h_proto;
 300                         offset += sizeof(*eth);
 301
 302                         /* Cap headers that we access via pointers at the
 303                          * end of the Ethernet header as our maximum alignment
 304                          * at that point is only 2 bytes.
 305                          */
 306                         if (NET_IP_ALIGN)
 307                                 *p_hlen = *p_nhoff + offset;
 308                 }
 309         } else { /* version 1, must be PPTP */
 310                 u8 _ppp_hdr[PPP_HDRLEN];
 311                 u8 *ppp_hdr;
 312
 313                 if (hdr->flags & GRE_ACK)
 314                         offset += sizeof(((struct pptp_gre_header *) 0)->ack);
 315
 316                 ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
 317                                                sizeof(_ppp_hdr),
 318                                                data, *p_hlen, _ppp_hdr);
 319                 if (!ppp_hdr)
 320                         return FLOW_DISSECT_RET_OUT_BAD;
 321
 322                 switch (PPP_PROTOCOL(ppp_hdr)) {
 323                 case PPP_IP:
 324                         *p_proto = htons(ETH_P_IP);
 325                         break;
 326                 case PPP_IPV6:
 327                         *p_proto = htons(ETH_P_IPV6);
 328                         break;
 329                 default:
 330                         /* Could probably catch some more like MPLS */
 331                         break;
 332                 }
 333
 334                 offset += PPP_HDRLEN;
 335         }
 336
 337         *p_nhoff += offset;
 338         key_control->flags |= FLOW_DIS_ENCAPSULATION;
 339         if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
 340                 return FLOW_DISSECT_RET_OUT_GOOD;
 341
 342         return FLOW_DISSECT_RET_OUT_PROTO_AGAIN;
 343 }
 344
 345 /**
 346  * __skb_flow_dissect - extract the flow_keys struct and return it
 347  * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
 348  * @flow_dissector: list of keys to dissect
 349  * @target_container: target structure to put dissected values into
 350  * @data: raw buffer pointer to the packet, if NULL use skb->data
 351  * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
 352  * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
 353  * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
 354  *
 355  * The function will try to retrieve individual keys into target specified
 356  * by flow_dissector from either the skbuff or a raw buffer specified by the
 357  * rest parameters.
 358  *
 359  * Caller must take care of zeroing target container memory.
 360  */
 361 bool __skb_flow_dissect(const struct sk_buff *skb,
 362                         struct flow_dissector *flow_dissector,
 363                         void *target_container,
 364                         void *data, __be16 proto, int nhoff, int hlen,
 365                         unsigned int flags)
 366 {
 367         struct flow_dissector_key_control *key_control;
 368         struct flow_dissector_key_basic *key_basic;
 369         struct flow_dissector_key_addrs *key_addrs;
 370         struct flow_dissector_key_ports *key_ports;
 371         struct flow_dissector_key_icmp *key_icmp;
 372         struct flow_dissector_key_tags *key_tags;
 373         struct flow_dissector_key_vlan *key_vlan;
 374         bool skip_vlan = false;
 375         u8 ip_proto = 0;
 376         bool ret;
 377
 378         if (!data) {
 379                 data = skb->data;
 380                 proto = skb_vlan_tag_present(skb) ?
 381                          skb->vlan_proto : skb->protocol;
 382                 nhoff = skb_network_offset(skb);
 383                 hlen = skb_headlen(skb);
 384         }
 385
 386         /* It is ensured by skb_flow_dissector_init() that control key will
 387          * be always present.
 388          */
 389         key_control = skb_flow_dissector_target(flow_dissector,
 390                                                 FLOW_DISSECTOR_KEY_CONTROL,
 391                                                 target_container);
 392
 393         /* It is ensured by skb_flow_dissector_init() that basic key will
 394          * be always present.
 395          */
 396         key_basic = skb_flow_dissector_target(flow_dissector,
 397                                               FLOW_DISSECTOR_KEY_BASIC,
 398                                               target_container);
 399
 400         if (dissector_uses_key(flow_dissector,
 401                                FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
 402                 struct ethhdr *eth = eth_hdr(skb);
 403                 struct flow_dissector_key_eth_addrs *key_eth_addrs;
 404
 405                 key_eth_addrs = skb_flow_dissector_target(flow_dissector,
 406                                                           FLOW_DISSECTOR_KEY_ETH_ADDRS,
 407                                                           target_container);
 408                 memcpy(key_eth_addrs, &eth->h_dest, sizeof(*key_eth_addrs));
 409         }
 410
 411 proto_again:
 412         switch (proto) {
 413         case htons(ETH_P_IP): {
 414                 const struct iphdr *iph;
 415                 struct iphdr _iph;
 416 ip:
 417                 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
 418                 if (!iph || iph->ihl < 5)
 419                         goto out_bad;
 420                 nhoff += iph->ihl * 4;
 421
 422                 ip_proto = iph->protocol;
 423
 424                 if (dissector_uses_key(flow_dissector,
 425                                        FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
 426                         key_addrs = skb_flow_dissector_target(flow_dissector,
 427                                                               FLOW_DISSECTOR_KEY_IPV4_ADDRS,
 428                                                               target_container);
 429
 430                         memcpy(&key_addrs->v4addrs, &iph->saddr,
 431                                sizeof(key_addrs->v4addrs));
 432                         key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
 433                 }
 434
 435                 if (ip_is_fragment(iph)) {
 436                         key_control->flags |= FLOW_DIS_IS_FRAGMENT;
 437
 438                         if (iph->frag_off & htons(IP_OFFSET)) {
 439                                 goto out_good;
 440                         } else {
 441                                 key_control->flags |= FLOW_DIS_FIRST_FRAG;
 442                                 if (!(flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG))
 443                                         goto out_good;
 444                         }
 445                 }
 446
 447                 if (flags & FLOW_DISSECTOR_F_STOP_AT_L3)
 448                         goto out_good;
 449
 450                 break;
 451         }
 452         case htons(ETH_P_IPV6): {
 453                 const struct ipv6hdr *iph;
 454                 struct ipv6hdr _iph;
 455
 456 ipv6:
 457                 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
 458                 if (!iph)
 459                         goto out_bad;
 460
 461                 ip_proto = iph->nexthdr;
 462                 nhoff += sizeof(struct ipv6hdr);
 463
 464                 if (dissector_uses_key(flow_dissector,
 465                                        FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
 466                         key_addrs = skb_flow_dissector_target(flow_dissector,
 467                                                               FLOW_DISSECTOR_KEY_IPV6_ADDRS,
 468                                                               target_container);
 469
 470                         memcpy(&key_addrs->v6addrs, &iph->saddr,
 471                                sizeof(key_addrs->v6addrs));
 472                         key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
 473                 }
 474
 475                 if ((dissector_uses_key(flow_dissector,
 476                                         FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
 477                      (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
 478                     ip6_flowlabel(iph)) {
 479                         __be32 flow_label = ip6_flowlabel(iph);
 480
 481                         if (dissector_uses_key(flow_dissector,
 482                                                FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
 483                                 key_tags = skb_flow_dissector_target(flow_dissector,
 484                                                                      FLOW_DISSECTOR_KEY_FLOW_LABEL,
 485                                                                      target_container);
 486                                 key_tags->flow_label = ntohl(flow_label);
 487                         }
 488                         if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)
 489                                 goto out_good;
 490                 }
 491
 492                 if (flags & FLOW_DISSECTOR_F_STOP_AT_L3)
 493                         goto out_good;
 494
 495                 break;
 496         }
 497         case htons(ETH_P_8021AD):
 498         case htons(ETH_P_8021Q): {
 499                 const struct vlan_hdr *vlan;
 500                 struct vlan_hdr _vlan;
 501                 bool vlan_tag_present = skb && skb_vlan_tag_present(skb);
 502
 503                 if (vlan_tag_present)
 504                         proto = skb->protocol;
 505
 506                 if (!vlan_tag_present || eth_type_vlan(skb->protocol)) {
 507                         vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
 508                                                     data, hlen, &_vlan);
 509                         if (!vlan)
 510                                 goto out_bad;
 511                         proto = vlan->h_vlan_encapsulated_proto;
 512                         nhoff += sizeof(*vlan);
 513                         if (skip_vlan)
 514                                 goto proto_again;
 515                 }
 516
 517                 skip_vlan = true;
 518                 if (dissector_uses_key(flow_dissector,
 519                                        FLOW_DISSECTOR_KEY_VLAN)) {
 520                         key_vlan = skb_flow_dissector_target(flow_dissector,
 521                                                              FLOW_DISSECTOR_KEY_VLAN,
 522                                                              target_container);
 523
 524                         if (vlan_tag_present) {
 525                                 key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
 526                                 key_vlan->vlan_priority =
 527                                         (skb_vlan_tag_get_prio(skb) >> VLAN_PRIO_SHIFT);
 528                         } else {
 529                                 key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
 530                                         VLAN_VID_MASK;
 531                                 key_vlan->vlan_priority =
 532                                         (ntohs(vlan->h_vlan_TCI) &
 533                                          VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
 534                         }
 535                 }
 536
 537                 goto proto_again;
 538         }
 539         case htons(ETH_P_PPP_SES): {
 540                 struct {
 541                         struct pppoe_hdr hdr;
 542                         __be16 proto;
 543                 } *hdr, _hdr;
 544                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
 545                 if (!hdr)
 546                         goto out_bad;
 547                 proto = hdr->proto;
 548                 nhoff += PPPOE_SES_HLEN;
 549                 switch (proto) {
 550                 case htons(PPP_IP):
 551                         goto ip;
 552                 case htons(PPP_IPV6):
 553                         goto ipv6;
 554                 default:
 555                         goto out_bad;
 556                 }
 557         }
 558         case htons(ETH_P_TIPC): {
 559                 struct {
 560                         __be32 pre[3];
 561                         __be32 srcnode;
 562                 } *hdr, _hdr;
 563                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
 564                 if (!hdr)
 565                         goto out_bad;
 566
 567                 if (dissector_uses_key(flow_dissector,
 568                                        FLOW_DISSECTOR_KEY_TIPC_ADDRS)) {
 569                         key_addrs = skb_flow_dissector_target(flow_dissector,
 570                                                               FLOW_DISSECTOR_KEY_TIPC_ADDRS,
 571                                                               target_container);
 572                         key_addrs->tipcaddrs.srcnode = hdr->srcnode;
 573                         key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC_ADDRS;
 574                 }
 575                 goto out_good;
 576         }
 577
 578         case htons(ETH_P_MPLS_UC):
 579         case htons(ETH_P_MPLS_MC):
 580 mpls:
 581                 switch (__skb_flow_dissect_mpls(skb, flow_dissector,
 582                                                 target_container, data,
 583                                                 nhoff, hlen)) {
 584                 case FLOW_DISSECT_RET_OUT_GOOD:
 585                         goto out_good;
 586                 case FLOW_DISSECT_RET_OUT_BAD:
 587                 default:
 588                         goto out_bad;
 589                 }
 590         case htons(ETH_P_FCOE):
 591                 if ((hlen - nhoff) < FCOE_HEADER_LEN)
 592                         goto out_bad;
 593
 594                 nhoff += FCOE_HEADER_LEN;
 595                 goto out_good;
 596
 597         case htons(ETH_P_ARP):
 598         case htons(ETH_P_RARP):
 599                 switch (__skb_flow_dissect_arp(skb, flow_dissector,
 600                                                target_container, data,
 601                                                nhoff, hlen)) {
 602                 case FLOW_DISSECT_RET_OUT_GOOD:
 603                         goto out_good;
 604                 case FLOW_DISSECT_RET_OUT_BAD:
 605                 default:
 606                         goto out_bad;
 607                 }
 608         default:
 609                 goto out_bad;
 610         }
 611
 612 ip_proto_again:
 613         switch (ip_proto) {
 614         case IPPROTO_GRE:
 615                 switch (__skb_flow_dissect_gre(skb, key_control, flow_dissector,
 616                                                target_container, data,
 617                                                &proto, &nhoff, &hlen, flags)) {
 618                 case FLOW_DISSECT_RET_OUT_GOOD:
 619                         goto out_good;
 620                 case FLOW_DISSECT_RET_OUT_BAD:
 621                         goto out_bad;
 622                 case FLOW_DISSECT_RET_OUT_PROTO_AGAIN:
 623                         goto proto_again;
 624                 }
 625         case NEXTHDR_HOP:
 626         case NEXTHDR_ROUTING:
 627         case NEXTHDR_DEST: {
 628                 u8 _opthdr[2], *opthdr;
 629
 630                 if (proto != htons(ETH_P_IPV6))
 631                         break;
 632
 633                 opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
 634                                               data, hlen, &_opthdr);
 635                 if (!opthdr)
 636                         goto out_bad;
 637
 638                 ip_proto = opthdr[0];
 639                 nhoff += (opthdr[1] + 1) << 3;
 640
 641                 goto ip_proto_again;
 642         }
 643         case NEXTHDR_FRAGMENT: {
 644                 struct frag_hdr _fh, *fh;
 645
 646                 if (proto != htons(ETH_P_IPV6))
 647                         break;
 648
 649                 fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
 650                                           data, hlen, &_fh);
 651
 652                 if (!fh)
 653                         goto out_bad;
 654
 655                 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
 656
 657                 nhoff += sizeof(_fh);
 658                 ip_proto = fh->nexthdr;
 659
 660                 if (!(fh->frag_off & htons(IP6_OFFSET))) {
 661                         key_control->flags |= FLOW_DIS_FIRST_FRAG;
 662                         if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG)
 663                                 goto ip_proto_again;
 664                 }
 665                 goto out_good;
 666         }
 667         case IPPROTO_IPIP:
 668                 proto = htons(ETH_P_IP);
 669
 670                 key_control->flags |= FLOW_DIS_ENCAPSULATION;
 671                 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
 672                         goto out_good;
 673
 674                 goto ip;
 675         case IPPROTO_IPV6:
 676                 proto = htons(ETH_P_IPV6);
 677
 678                 key_control->flags |= FLOW_DIS_ENCAPSULATION;
 679                 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
 680                         goto out_good;
 681
 682                 goto ipv6;
 683         case IPPROTO_MPLS:
 684                 proto = htons(ETH_P_MPLS_UC);
 685                 goto mpls;
 686         default:
 687                 break;
 688         }
 689
 690         if (dissector_uses_key(flow_dissector,
 691                                FLOW_DISSECTOR_KEY_PORTS)) {
 692                 key_ports = skb_flow_dissector_target(flow_dissector,
 693                                                       FLOW_DISSECTOR_KEY_PORTS,
 694                                                       target_container);
 695                 key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
 696                                                         data, hlen);
 697         }
 698
 699         if (dissector_uses_key(flow_dissector,
 700                                FLOW_DISSECTOR_KEY_ICMP)) {
 701                 key_icmp = skb_flow_dissector_target(flow_dissector,
 702                                                      FLOW_DISSECTOR_KEY_ICMP,
 703                                                      target_container);
 704                 key_icmp->icmp = skb_flow_get_be16(skb, nhoff, data, hlen);
 705         }
 706
 707 out_good:
 708         ret = true;
 709
 710         key_control->thoff = (u16)nhoff;
 711 out:
 712         key_basic->n_proto = proto;
 713         key_basic->ip_proto = ip_proto;
 714
 715         return ret;
 716
 717 out_bad:
 718         ret = false;
 719         key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
 720         goto out;
 721 }
 722 EXPORT_SYMBOL(__skb_flow_dissect);
 723
 724 static u32 hashrnd __read_mostly;
 725 static __always_inline void __flow_hash_secret_init(void)
 726 {
 727         net_get_random_once(&hashrnd, sizeof(hashrnd));
 728 }
 729
 730 static __always_inline u32 __flow_hash_words(const u32 *words, u32 length,
 731                                              u32 keyval)
 732 {
 733         return jhash2(words, length, keyval);
 734 }
 735
 736 static inline const u32 *flow_keys_hash_start(const struct flow_keys *flow)
 737 {
 738         const void *p = flow;
 739
 740         BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % sizeof(u32));
 741         return (const u32 *)(p + FLOW_KEYS_HASH_OFFSET);
 742 }
 743
 744 static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
 745 {
 746         size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
 747         BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
 748         BUILD_BUG_ON(offsetof(typeof(*flow), addrs) !=
 749                      sizeof(*flow) - sizeof(flow->addrs));
 750
 751         switch (flow->control.addr_type) {
 752         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
 753                 diff -= sizeof(flow->addrs.v4addrs);
 754                 break;
 755         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
 756                 diff -= sizeof(flow->addrs.v6addrs);
 757                 break;
 758         case FLOW_DISSECTOR_KEY_TIPC_ADDRS:
 759                 diff -= sizeof(flow->addrs.tipcaddrs);
 760                 break;
 761         }
 762         return (sizeof(*flow) - diff) / sizeof(u32);
 763 }
 764
 765 __be32 flow_get_u32_src(const struct flow_keys *flow)
 766 {
 767         switch (flow->control.addr_type) {
 768         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
 769                 return flow->addrs.v4addrs.src;
 770         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
 771                 return (__force __be32)ipv6_addr_hash(
 772                         &flow->addrs.v6addrs.src);
 773         case FLOW_DISSECTOR_KEY_TIPC_ADDRS:
 774                 return flow->addrs.tipcaddrs.srcnode;
 775         default:
 776                 return 0;
 777         }
 778 }
 779 EXPORT_SYMBOL(flow_get_u32_src);
 780
 781 __be32 flow_get_u32_dst(const struct flow_keys *flow)
 782 {
 783         switch (flow->control.addr_type) {
 784         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
 785                 return flow->addrs.v4addrs.dst;
 786         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
 787                 return (__force __be32)ipv6_addr_hash(
 788                         &flow->addrs.v6addrs.dst);
 789         default:
 790                 return 0;
 791         }
 792 }
 793 EXPORT_SYMBOL(flow_get_u32_dst);
 794
 795 static inline void __flow_hash_consistentify(struct flow_keys *keys)
 796 {
 797         int addr_diff, i;
 798
 799         switch (keys->control.addr_type) {
 800         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
 801                 addr_diff = (__force u32)keys->addrs.v4addrs.dst -
 802                             (__force u32)keys->addrs.v4addrs.src;
 803                 if ((addr_diff < 0) ||
 804                     (addr_diff == 0 &&
 805                      ((__force u16)keys->ports.dst <
 806                       (__force u16)keys->ports.src))) {
 807                         swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
 808                         swap(keys->ports.src, keys->ports.dst);
 809                 }
 810                 break;
 811         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
 812                 addr_diff = memcmp(&keys->addrs.v6addrs.dst,
 813                                    &keys->addrs.v6addrs.src,
 814                                    sizeof(keys->addrs.v6addrs.dst));
 815                 if ((addr_diff < 0) ||
 816                     (addr_diff == 0 &&
 817                      ((__force u16)keys->ports.dst <
 818                       (__force u16)keys->ports.src))) {
 819                         for (i = 0; i < 4; i++)
 820                                 swap(keys->addrs.v6addrs.src.s6_addr32[i],
 821                                      keys->addrs.v6addrs.dst.s6_addr32[i]);
 822                         swap(keys->ports.src, keys->ports.dst);
 823                 }
 824                 break;
 825         }
 826 }
 827
 828 static inline u32 __flow_hash_from_keys(struct flow_keys *keys, u32 keyval)
 829 {
 830         u32 hash;
 831
 832         __flow_hash_consistentify(keys);
 833
 834         hash = __flow_hash_words(flow_keys_hash_start(keys),
 835                                  flow_keys_hash_length(keys), keyval);
 836         if (!hash)
 837                 hash = 1;
 838
 839         return hash;
 840 }
 841
 842 u32 flow_hash_from_keys(struct flow_keys *keys)
 843 {
 844         __flow_hash_secret_init();
 845         return __flow_hash_from_keys(keys, hashrnd);
 846 }
 847 EXPORT_SYMBOL(flow_hash_from_keys);
 848
 849 static inline u32 ___skb_get_hash(const struct sk_buff *skb,
 850                                   struct flow_keys *keys, u32 keyval)
 851 {
 852         skb_flow_dissect_flow_keys(skb, keys,
 853                                    FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
 854
 855         return __flow_hash_from_keys(keys, keyval);
 856 }
 857
 858 struct _flow_keys_digest_data {
 859         __be16  n_proto;
 860         u8      ip_proto;
 861         u8      padding;
 862         __be32  ports;
 863         __be32  src;
 864         __be32  dst;
 865 };
 866
 867 void make_flow_keys_digest(struct flow_keys_digest *digest,
 868                            const struct flow_keys *flow)
 869 {
 870         struct _flow_keys_digest_data *data =
 871             (struct _flow_keys_digest_data *)digest;
 872
 873         BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));
 874
 875         memset(digest, 0, sizeof(*digest));
 876
 877         data->n_proto = flow->basic.n_proto;
 878         data->ip_proto = flow->basic.ip_proto;
 879         data->ports = flow->ports.ports;
 880         data->src = flow->addrs.v4addrs.src;
 881         data->dst = flow->addrs.v4addrs.dst;
 882 }
 883 EXPORT_SYMBOL(make_flow_keys_digest);
 884
 885 static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
 886
 887 u32 __skb_get_hash_symmetric(const struct sk_buff *skb)
 888 {
 889         struct flow_keys keys;
 890
 891         __flow_hash_secret_init();
 892
 893         memset(&keys, 0, sizeof(keys));
 894         __skb_flow_dissect(skb, &flow_keys_dissector_symmetric, &keys,
 895                            NULL, 0, 0, 0,
 896                            FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
 897
 898         return __flow_hash_from_keys(&keys, hashrnd);
 899 }
 900 EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric);
 901
 902 /**
 903  * __skb_get_hash: calculate a flow hash
 904  * @skb: sk_buff to calculate flow hash from
 905  *
 906  * This function calculates a flow hash based on src/dst addresses
 907  * and src/dst port numbers.  Sets hash in skb to non-zero hash value
 908  * on success, zero indicates no valid hash.  Also, sets l4_hash in skb
 909  * if hash is a canonical 4-tuple hash over transport ports.
 910  */
 911 void __skb_get_hash(struct sk_buff *skb)
 912 {
 913         struct flow_keys keys;
 914         u32 hash;
 915
 916         __flow_hash_secret_init();
 917
 918         hash = ___skb_get_hash(skb, &keys, hashrnd);
 919
 920         __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
 921 }
 922 EXPORT_SYMBOL(__skb_get_hash);
 923
 924 __u32 skb_get_hash_perturb(const struct sk_buff *skb, u32 perturb)
 925 {
 926         struct flow_keys keys;
 927
 928         return ___skb_get_hash(skb, &keys, perturb);
 929 }
 930 EXPORT_SYMBOL(skb_get_hash_perturb);
 931
 932 __u32 __skb_get_hash_flowi6(struct sk_buff *skb, const struct flowi6 *fl6)
 933 {
 934         struct flow_keys keys;
 935
 936         memset(&keys, 0, sizeof(keys));
 937
 938         memcpy(&keys.addrs.v6addrs.src, &fl6->saddr,
 939                sizeof(keys.addrs.v6addrs.src));
 940         memcpy(&keys.addrs.v6addrs.dst, &fl6->daddr,
 941                sizeof(keys.addrs.v6addrs.dst));
 942         keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
 943         keys.ports.src = fl6->fl6_sport;
 944         keys.ports.dst = fl6->fl6_dport;
 945         keys.keyid.keyid = fl6->fl6_gre_key;
 946         keys.tags.flow_label = (__force u32)fl6->flowlabel;
 947         keys.basic.ip_proto = fl6->flowi6_proto;
 948
 949         __skb_set_sw_hash(skb, flow_hash_from_keys(&keys),
 950                           flow_keys_have_l4(&keys));
 951
 952         return skb->hash;
 953 }
 954 EXPORT_SYMBOL(__skb_get_hash_flowi6);
 955
 956 __u32 __skb_get_hash_flowi4(struct sk_buff *skb, const struct flowi4 *fl4)
 957 {
 958         struct flow_keys keys;
 959
 960         memset(&keys, 0, sizeof(keys));
 961
 962         keys.addrs.v4addrs.src = fl4->saddr;
 963         keys.addrs.v4addrs.dst = fl4->daddr;
 964         keys.control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
 965         keys.ports.src = fl4->fl4_sport;
 966         keys.ports.dst = fl4->fl4_dport;
 967         keys.keyid.keyid = fl4->fl4_gre_key;
 968         keys.basic.ip_proto = fl4->flowi4_proto;
 969
 970         __skb_set_sw_hash(skb, flow_hash_from_keys(&keys),
 971                           flow_keys_have_l4(&keys));
 972
 973         return skb->hash;
 974 }
 975 EXPORT_SYMBOL(__skb_get_hash_flowi4);
 976
 977 u32 __skb_get_poff(const struct sk_buff *skb, void *data,
 978                    const struct flow_keys *keys, int hlen)
 979 {
 980         u32 poff = keys->control.thoff;
 981
 982         /* skip L4 headers for fragments after the first */
 983         if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
 984             !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
 985                 return poff;
 986
 987         switch (keys->basic.ip_proto) {
 988         case IPPROTO_TCP: {
 989                 /* access doff as u8 to avoid unaligned access */
 990                 const u8 *doff;
 991                 u8 _doff;
 992
 993                 doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
 994                                             data, hlen, &_doff);
 995                 if (!doff)
 996                         return poff;
 997
 998                 poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
 999                 break;
1000         }
1001         case IPPROTO_UDP:
1002         case IPPROTO_UDPLITE:
1003                 poff += sizeof(struct udphdr);
1004                 break;
1005         /* For the rest, we do not really care about header
1006          * extensions at this point for now.
1007          */
1008         case IPPROTO_ICMP:
1009                 poff += sizeof(struct icmphdr);
1010                 break;
1011         case IPPROTO_ICMPV6:
1012                 poff += sizeof(struct icmp6hdr);
1013                 break;
1014         case IPPROTO_IGMP:
1015                 poff += sizeof(struct igmphdr);
1016                 break;
1017         case IPPROTO_DCCP:
1018                 poff += sizeof(struct dccp_hdr);
1019                 break;
1020         case IPPROTO_SCTP:
1021                 poff += sizeof(struct sctphdr);
1022                 break;
1023         }
1024
1025         return poff;
1026 }
1027
1028 /**
1029  * skb_get_poff - get the offset to the payload
1030  * @skb: sk_buff to get the payload offset from
1031  *
1032  * The function will get the offset to the payload as far as it could
1033  * be dissected.  The main user is currently BPF, so that we can dynamically
1034  * truncate packets without needing to push actual payload to the user
1035  * space and can analyze headers only, instead.
1036  */
1037 u32 skb_get_poff(const struct sk_buff *skb)
1038 {
1039         struct flow_keys keys;
1040
1041         if (!skb_flow_dissect_flow_keys(skb, &keys, 0))
1042                 return 0;
1043
1044         return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
1045 }
1046
1047 __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
1048 {
1049         memset(keys, 0, sizeof(*keys));
1050
1051         memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
1052             sizeof(keys->addrs.v6addrs.src));
1053         memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
1054             sizeof(keys->addrs.v6addrs.dst));
1055         keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1056         keys->ports.src = fl6->fl6_sport;
1057         keys->ports.dst = fl6->fl6_dport;
1058         keys->keyid.keyid = fl6->fl6_gre_key;
1059         keys->tags.flow_label = (__force u32)fl6->flowlabel;
1060         keys->basic.ip_proto = fl6->flowi6_proto;
1061
1062         return flow_hash_from_keys(keys);
1063 }
1064 EXPORT_SYMBOL(__get_hash_from_flowi6);
1065
1066 __u32 __get_hash_from_flowi4(const struct flowi4 *fl4, struct flow_keys *keys)
1067 {
1068         memset(keys, 0, sizeof(*keys));
1069
1070         keys->addrs.v4addrs.src = fl4->saddr;
1071         keys->addrs.v4addrs.dst = fl4->daddr;
1072         keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
1073         keys->ports.src = fl4->fl4_sport;
1074         keys->ports.dst = fl4->fl4_dport;
1075         keys->keyid.keyid = fl4->fl4_gre_key;
1076         keys->basic.ip_proto = fl4->flowi4_proto;
1077
1078         return flow_hash_from_keys(keys);
1079 }
1080 EXPORT_SYMBOL(__get_hash_from_flowi4);
1081
1082 static const struct flow_dissector_key flow_keys_dissector_keys[] = {
1083         {
1084                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1085                 .offset = offsetof(struct flow_keys, control),
1086         },
1087         {
1088                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1089                 .offset = offsetof(struct flow_keys, basic),
1090         },
1091         {
1092                 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1093                 .offset = offsetof(struct flow_keys, addrs.v4addrs),
1094         },
1095         {
1096                 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1097                 .offset = offsetof(struct flow_keys, addrs.v6addrs),
1098         },
1099         {
1100                 .key_id = FLOW_DISSECTOR_KEY_TIPC_ADDRS,
1101                 .offset = offsetof(struct flow_keys, addrs.tipcaddrs),
1102         },
1103         {
1104                 .key_id = FLOW_DISSECTOR_KEY_PORTS,
1105                 .offset = offsetof(struct flow_keys, ports),
1106         },
1107         {
1108                 .key_id = FLOW_DISSECTOR_KEY_VLAN,
1109                 .offset = offsetof(struct flow_keys, vlan),
1110         },
1111         {
1112                 .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
1113                 .offset = offsetof(struct flow_keys, tags),
1114         },
1115         {
1116                 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
1117                 .offset = offsetof(struct flow_keys, keyid),
1118         },
1119 };
1120
1121 static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
1122         {
1123                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1124                 .offset = offsetof(struct flow_keys, control),
1125         },
1126         {
1127                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1128                 .offset = offsetof(struct flow_keys, basic),
1129         },
1130         {
1131                 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1132                 .offset = offsetof(struct flow_keys, addrs.v4addrs),
1133         },
1134         {
1135                 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1136                 .offset = offsetof(struct flow_keys, addrs.v6addrs),
1137         },
1138         {
1139                 .key_id = FLOW_DISSECTOR_KEY_PORTS,
1140                 .offset = offsetof(struct flow_keys, ports),
1141         },
1142 };
1143
1144 static const struct flow_dissector_key flow_keys_buf_dissector_keys[] = {
1145         {
1146                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1147                 .offset = offsetof(struct flow_keys, control),
1148         },
1149         {
1150                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1151                 .offset = offsetof(struct flow_keys, basic),
1152         },
1153 };
1154
1155 struct flow_dissector flow_keys_dissector __read_mostly;
1156 EXPORT_SYMBOL(flow_keys_dissector);
1157
1158 struct flow_dissector flow_keys_buf_dissector __read_mostly;
1159
1160 static int __init init_default_flow_dissectors(void)
1161 {
1162         skb_flow_dissector_init(&flow_keys_dissector,
1163                                 flow_keys_dissector_keys,
1164                                 ARRAY_SIZE(flow_keys_dissector_keys));
1165         skb_flow_dissector_init(&flow_keys_dissector_symmetric,
1166                                 flow_keys_dissector_symmetric_keys,
1167                                 ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
1168         skb_flow_dissector_init(&flow_keys_buf_dissector,
1169                                 flow_keys_buf_dissector_keys,
1170                                 ARRAY_SIZE(flow_keys_buf_dissector_keys));
1171         return 0;
1172 }
1173
1174 core_initcall(init_default_flow_dissectors);