net/core/flow_dissector.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 #include <linux/kernel.h>
   3 #include <linux/skbuff.h>
   4 #include <linux/export.h>
   5 #include <linux/ip.h>
   6 #include <linux/ipv6.h>
   7 #include <linux/if_vlan.h>
   8 #include <linux/filter.h>
   9 #include <net/dsa.h>
  10 #include <net/dst_metadata.h>
  11 #include <net/ip.h>
  12 #include <net/ipv6.h>
  13 #include <net/gre.h>
  14 #include <net/pptp.h>
  15 #include <net/tipc.h>
  16 #include <linux/igmp.h>
  17 #include <linux/icmp.h>
  18 #include <linux/sctp.h>
  19 #include <linux/dccp.h>
  20 #include <linux/if_tunnel.h>
  21 #include <linux/if_pppox.h>
  22 #include <linux/ppp_defs.h>
  23 #include <linux/stddef.h>
  24 #include <linux/if_ether.h>
  25 #include <linux/if_hsr.h>
  26 #include <linux/mpls.h>
  27 #include <linux/tcp.h>
  28 #include <linux/ptp_classify.h>
  29 #include <net/flow_dissector.h>
  30 #include <scsi/fc/fc_fcoe.h>
  31 #include <uapi/linux/batadv_packet.h>
  32 #include <linux/bpf.h>
  33 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
  34 #include <net/netfilter/nf_conntrack_core.h>
  35 #include <net/netfilter/nf_conntrack_labels.h>
  36 #endif
  37 #include <linux/bpf-netns.h>
  38
  39 static void dissector_set_key(struct flow_dissector *flow_dissector,
  40                               enum flow_dissector_key_id key_id)
  41 {
  42         flow_dissector->used_keys |= (1 << key_id);
  43 }
  44
  45 void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
  46                              const struct flow_dissector_key *key,
  47                              unsigned int key_count)
  48 {
  49         unsigned int i;
  50
  51         memset(flow_dissector, 0, sizeof(*flow_dissector));
  52
  53         for (i = 0; i < key_count; i++, key++) {
  54                 /* User should make sure that every key target offset is within
  55                  * boundaries of unsigned short.
  56                  */
  57                 BUG_ON(key->offset > USHRT_MAX);
  58                 BUG_ON(dissector_uses_key(flow_dissector,
  59                                           key->key_id));
  60
  61                 dissector_set_key(flow_dissector, key->key_id);
  62                 flow_dissector->offset[key->key_id] = key->offset;
  63         }
  64
  65         /* Ensure that the dissector always includes control and basic key.
  66          * That way we are able to avoid handling lack of these in fast path.
  67          */
  68         BUG_ON(!dissector_uses_key(flow_dissector,
  69                                    FLOW_DISSECTOR_KEY_CONTROL));
  70         BUG_ON(!dissector_uses_key(flow_dissector,
  71                                    FLOW_DISSECTOR_KEY_BASIC));
  72 }
  73 EXPORT_SYMBOL(skb_flow_dissector_init);
  74
  75 #ifdef CONFIG_BPF_SYSCALL
  76 int flow_dissector_bpf_prog_attach_check(struct net *net,
  77                                          struct bpf_prog *prog)
  78 {
  79         enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;
  80
  81         if (net == &init_net) {
  82                 /* BPF flow dissector in the root namespace overrides
  83                  * any per-net-namespace one. When attaching to root,
  84                  * make sure we don't have any BPF program attached
  85                  * to the non-root namespaces.
  86                  */
  87                 struct net *ns;
  88
  89                 for_each_net(ns) {
  90                         if (ns == &init_net)
  91                                 continue;
  92                         if (rcu_access_pointer(ns->bpf.run_array[type]))
  93                                 return -EEXIST;
  94                 }
  95         } else {
  96                 /* Make sure root flow dissector is not attached
  97                  * when attaching to the non-root namespace.
  98                  */
  99                 if (rcu_access_pointer(init_net.bpf.run_array[type]))
 100                         return -EEXIST;
 101         }
 102
 103         return 0;
 104 }
 105 #endif /* CONFIG_BPF_SYSCALL */
 106
 107 /**
 108  * __skb_flow_get_ports - extract the upper layer ports and return them
 109  * @skb: sk_buff to extract the ports from
 110  * @thoff: transport header offset
 111  * @ip_proto: protocol for which to get port offset
 112  * @data: raw buffer pointer to the packet, if NULL use skb->data
 113  * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
 114  *
 115  * The function will try to retrieve the ports at offset thoff + poff where poff
 116  * is the protocol port offset returned from proto_ports_offset
 117  */
 118 __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
 119                             const void *data, int hlen)
 120 {
 121         int poff = proto_ports_offset(ip_proto);
 122
 123         if (!data) {
 124                 data = skb->data;
 125                 hlen = skb_headlen(skb);
 126         }
 127
 128         if (poff >= 0) {
 129                 __be32 *ports, _ports;
 130
 131                 ports = __skb_header_pointer(skb, thoff + poff,
 132                                              sizeof(_ports), data, hlen, &_ports);
 133                 if (ports)
 134                         return *ports;
 135         }
 136
 137         return 0;
 138 }
 139 EXPORT_SYMBOL(__skb_flow_get_ports);
 140
 141 static bool icmp_has_id(u8 type)
 142 {
 143         switch (type) {
 144         case ICMP_ECHO:
 145         case ICMP_ECHOREPLY:
 146         case ICMP_TIMESTAMP:
 147         case ICMP_TIMESTAMPREPLY:
 148         case ICMPV6_ECHO_REQUEST:
 149         case ICMPV6_ECHO_REPLY:
 150                 return true;
 151         }
 152
 153         return false;
 154 }
 155
 156 /**
 157  * skb_flow_get_icmp_tci - extract ICMP(6) Type, Code and Identifier fields
 158  * @skb: sk_buff to extract from
 159  * @key_icmp: struct flow_dissector_key_icmp to fill
 160  * @data: raw buffer pointer to the packet
 161  * @thoff: offset to extract at
 162  * @hlen: packet header length
 163  */
 164 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
 165                            struct flow_dissector_key_icmp *key_icmp,
 166                            const void *data, int thoff, int hlen)
 167 {
 168         struct icmphdr *ih, _ih;
 169
 170         ih = __skb_header_pointer(skb, thoff, sizeof(_ih), data, hlen, &_ih);
 171         if (!ih)
 172                 return;
 173
 174         key_icmp->type = ih->type;
 175         key_icmp->code = ih->code;
 176
 177         /* As we use 0 to signal that the Id field is not present,
 178          * avoid confusion with packets without such field
 179          */
 180         if (icmp_has_id(ih->type))
 181                 key_icmp->id = ih->un.echo.id ? ntohs(ih->un.echo.id) : 1;
 182         else
 183                 key_icmp->id = 0;
 184 }
 185 EXPORT_SYMBOL(skb_flow_get_icmp_tci);
 186
 187 /* If FLOW_DISSECTOR_KEY_ICMP is set, dissect an ICMP packet
 188  * using skb_flow_get_icmp_tci().
 189  */
 190 static void __skb_flow_dissect_icmp(const struct sk_buff *skb,
 191                                     struct flow_dissector *flow_dissector,
 192                                     void *target_container, const void *data,
 193                                     int thoff, int hlen)
 194 {
 195         struct flow_dissector_key_icmp *key_icmp;
 196
 197         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ICMP))
 198                 return;
 199
 200         key_icmp = skb_flow_dissector_target(flow_dissector,
 201                                              FLOW_DISSECTOR_KEY_ICMP,
 202                                              target_container);
 203
 204         skb_flow_get_icmp_tci(skb, key_icmp, data, thoff, hlen);
 205 }
 206
 207 static void __skb_flow_dissect_l2tpv3(const struct sk_buff *skb,
 208                                       struct flow_dissector *flow_dissector,
 209                                       void *target_container, const void *data,
 210                                       int nhoff, int hlen)
 211 {
 212         struct flow_dissector_key_l2tpv3 *key_l2tpv3;
 213         struct {
 214                 __be32 session_id;
 215         } *hdr, _hdr;
 216
 217         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_L2TPV3))
 218                 return;
 219
 220         hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
 221         if (!hdr)
 222                 return;
 223
 224         key_l2tpv3 = skb_flow_dissector_target(flow_dissector,
 225                                                FLOW_DISSECTOR_KEY_L2TPV3,
 226                                                target_container);
 227
 228         key_l2tpv3->session_id = hdr->session_id;
 229 }
 230
 231 void skb_flow_dissect_meta(const struct sk_buff *skb,
 232                            struct flow_dissector *flow_dissector,
 233                            void *target_container)
 234 {
 235         struct flow_dissector_key_meta *meta;
 236
 237         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_META))
 238                 return;
 239
 240         meta = skb_flow_dissector_target(flow_dissector,
 241                                          FLOW_DISSECTOR_KEY_META,
 242                                          target_container);
 243         meta->ingress_ifindex = skb->skb_iif;
 244 }
 245 EXPORT_SYMBOL(skb_flow_dissect_meta);
 246
 247 static void
 248 skb_flow_dissect_set_enc_addr_type(enum flow_dissector_key_id type,
 249                                    struct flow_dissector *flow_dissector,
 250                                    void *target_container)
 251 {
 252         struct flow_dissector_key_control *ctrl;
 253
 254         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_CONTROL))
 255                 return;
 256
 257         ctrl = skb_flow_dissector_target(flow_dissector,
 258                                          FLOW_DISSECTOR_KEY_ENC_CONTROL,
 259                                          target_container);
 260         ctrl->addr_type = type;
 261 }
 262
 263 void
 264 skb_flow_dissect_ct(const struct sk_buff *skb,
 265                     struct flow_dissector *flow_dissector,
 266                     void *target_container, u16 *ctinfo_map,
 267                     size_t mapsize, bool post_ct, u16 zone)
 268 {
 269 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
 270         struct flow_dissector_key_ct *key;
 271         enum ip_conntrack_info ctinfo;
 272         struct nf_conn_labels *cl;
 273         struct nf_conn *ct;
 274
 275         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_CT))
 276                 return;
 277
 278         ct = nf_ct_get(skb, &ctinfo);
 279         if (!ct && !post_ct)
 280                 return;
 281
 282         key = skb_flow_dissector_target(flow_dissector,
 283                                         FLOW_DISSECTOR_KEY_CT,
 284                                         target_container);
 285
 286         if (!ct) {
 287                 key->ct_state = TCA_FLOWER_KEY_CT_FLAGS_TRACKED |
 288                                 TCA_FLOWER_KEY_CT_FLAGS_INVALID;
 289                 key->ct_zone = zone;
 290                 return;
 291         }
 292
 293         if (ctinfo < mapsize)
 294                 key->ct_state = ctinfo_map[ctinfo];
 295 #if IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)
 296         key->ct_zone = ct->zone.id;
 297 #endif
 298 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 299         key->ct_mark = READ_ONCE(ct->mark);
 300 #endif
 301
 302         cl = nf_ct_labels_find(ct);
 303         if (cl)
 304                 memcpy(key->ct_labels, cl->bits, sizeof(key->ct_labels));
 305 #endif /* CONFIG_NF_CONNTRACK */
 306 }
 307 EXPORT_SYMBOL(skb_flow_dissect_ct);
 308
 309 void
 310 skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
 311                              struct flow_dissector *flow_dissector,
 312                              void *target_container)
 313 {
 314         struct ip_tunnel_info *info;
 315         struct ip_tunnel_key *key;
 316
 317         /* A quick check to see if there might be something to do. */
 318         if (!dissector_uses_key(flow_dissector,
 319                                 FLOW_DISSECTOR_KEY_ENC_KEYID) &&
 320             !dissector_uses_key(flow_dissector,
 321                                 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS) &&
 322             !dissector_uses_key(flow_dissector,
 323                                 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS) &&
 324             !dissector_uses_key(flow_dissector,
 325                                 FLOW_DISSECTOR_KEY_ENC_CONTROL) &&
 326             !dissector_uses_key(flow_dissector,
 327                                 FLOW_DISSECTOR_KEY_ENC_PORTS) &&
 328             !dissector_uses_key(flow_dissector,
 329                                 FLOW_DISSECTOR_KEY_ENC_IP) &&
 330             !dissector_uses_key(flow_dissector,
 331                                 FLOW_DISSECTOR_KEY_ENC_OPTS))
 332                 return;
 333
 334         info = skb_tunnel_info(skb);
 335         if (!info)
 336                 return;
 337
 338         key = &info->key;
 339
 340         switch (ip_tunnel_info_af(info)) {
 341         case AF_INET:
 342                 skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV4_ADDRS,
 343                                                    flow_dissector,
 344                                                    target_container);
 345                 if (dissector_uses_key(flow_dissector,
 346                                        FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS)) {
 347                         struct flow_dissector_key_ipv4_addrs *ipv4;
 348
 349                         ipv4 = skb_flow_dissector_target(flow_dissector,
 350                                                          FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS,
 351                                                          target_container);
 352                         ipv4->src = key->u.ipv4.src;
 353                         ipv4->dst = key->u.ipv4.dst;
 354                 }
 355                 break;
 356         case AF_INET6:
 357                 skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV6_ADDRS,
 358                                                    flow_dissector,
 359                                                    target_container);
 360                 if (dissector_uses_key(flow_dissector,
 361                                        FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS)) {
 362                         struct flow_dissector_key_ipv6_addrs *ipv6;
 363
 364                         ipv6 = skb_flow_dissector_target(flow_dissector,
 365                                                          FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS,
 366                                                          target_container);
 367                         ipv6->src = key->u.ipv6.src;
 368                         ipv6->dst = key->u.ipv6.dst;
 369                 }
 370                 break;
 371         }
 372
 373         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_KEYID)) {
 374                 struct flow_dissector_key_keyid *keyid;
 375
 376                 keyid = skb_flow_dissector_target(flow_dissector,
 377                                                   FLOW_DISSECTOR_KEY_ENC_KEYID,
 378                                                   target_container);
 379                 keyid->keyid = tunnel_id_to_key32(key->tun_id);
 380         }
 381
 382         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_PORTS)) {
 383                 struct flow_dissector_key_ports *tp;
 384
 385                 tp = skb_flow_dissector_target(flow_dissector,
 386                                                FLOW_DISSECTOR_KEY_ENC_PORTS,
 387                                                target_container);
 388                 tp->src = key->tp_src;
 389                 tp->dst = key->tp_dst;
 390         }
 391
 392         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_IP)) {
 393                 struct flow_dissector_key_ip *ip;
 394
 395                 ip = skb_flow_dissector_target(flow_dissector,
 396                                                FLOW_DISSECTOR_KEY_ENC_IP,
 397                                                target_container);
 398                 ip->tos = key->tos;
 399                 ip->ttl = key->ttl;
 400         }
 401
 402         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_OPTS)) {
 403                 struct flow_dissector_key_enc_opts *enc_opt;
 404
 405                 enc_opt = skb_flow_dissector_target(flow_dissector,
 406                                                     FLOW_DISSECTOR_KEY_ENC_OPTS,
 407                                                     target_container);
 408
 409                 if (info->options_len) {
 410                         enc_opt->len = info->options_len;
 411                         ip_tunnel_info_opts_get(enc_opt->data, info);
 412                         enc_opt->dst_opt_type = info->key.tun_flags &
 413                                                 TUNNEL_OPTIONS_PRESENT;
 414                 }
 415         }
 416 }
 417 EXPORT_SYMBOL(skb_flow_dissect_tunnel_info);
 418
 419 void skb_flow_dissect_hash(const struct sk_buff *skb,
 420                            struct flow_dissector *flow_dissector,
 421                            void *target_container)
 422 {
 423         struct flow_dissector_key_hash *key;
 424
 425         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_HASH))
 426                 return;
 427
 428         key = skb_flow_dissector_target(flow_dissector,
 429                                         FLOW_DISSECTOR_KEY_HASH,
 430                                         target_container);
 431
 432         key->hash = skb_get_hash_raw(skb);
 433 }
 434 EXPORT_SYMBOL(skb_flow_dissect_hash);
 435
 436 static enum flow_dissect_ret
 437 __skb_flow_dissect_mpls(const struct sk_buff *skb,
 438                         struct flow_dissector *flow_dissector,
 439                         void *target_container, const void *data, int nhoff,
 440                         int hlen, int lse_index, bool *entropy_label)
 441 {
 442         struct mpls_label *hdr, _hdr;
 443         u32 entry, label, bos;
 444
 445         if (!dissector_uses_key(flow_dissector,
 446                                 FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
 447             !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
 448                 return FLOW_DISSECT_RET_OUT_GOOD;
 449
 450         if (lse_index >= FLOW_DIS_MPLS_MAX)
 451                 return FLOW_DISSECT_RET_OUT_GOOD;
 452
 453         hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
 454                                    hlen, &_hdr);
 455         if (!hdr)
 456                 return FLOW_DISSECT_RET_OUT_BAD;
 457
 458         entry = ntohl(hdr->entry);
 459         label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
 460         bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;
 461
 462         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
 463                 struct flow_dissector_key_mpls *key_mpls;
 464                 struct flow_dissector_mpls_lse *lse;
 465
 466                 key_mpls = skb_flow_dissector_target(flow_dissector,
 467                                                      FLOW_DISSECTOR_KEY_MPLS,
 468                                                      target_container);
 469                 lse = &key_mpls->ls[lse_index];
 470
 471                 lse->mpls_ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
 472                 lse->mpls_bos = bos;
 473                 lse->mpls_tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
 474                 lse->mpls_label = label;
 475                 dissector_set_mpls_lse(key_mpls, lse_index);
 476         }
 477
 478         if (*entropy_label &&
 479             dissector_uses_key(flow_dissector,
 480                                FLOW_DISSECTOR_KEY_MPLS_ENTROPY)) {
 481                 struct flow_dissector_key_keyid *key_keyid;
 482
 483                 key_keyid = skb_flow_dissector_target(flow_dissector,
 484                                                       FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
 485                                                       target_container);
 486                 key_keyid->keyid = cpu_to_be32(label);
 487         }
 488
 489         *entropy_label = label == MPLS_LABEL_ENTROPY;
 490
 491         return bos ? FLOW_DISSECT_RET_OUT_GOOD : FLOW_DISSECT_RET_PROTO_AGAIN;
 492 }
 493
 494 static enum flow_dissect_ret
 495 __skb_flow_dissect_arp(const struct sk_buff *skb,
 496                        struct flow_dissector *flow_dissector,
 497                        void *target_container, const void *data,
 498                        int nhoff, int hlen)
 499 {
 500         struct flow_dissector_key_arp *key_arp;
 501         struct {
 502                 unsigned char ar_sha[ETH_ALEN];
 503                 unsigned char ar_sip[4];
 504                 unsigned char ar_tha[ETH_ALEN];
 505                 unsigned char ar_tip[4];
 506         } *arp_eth, _arp_eth;
 507         const struct arphdr *arp;
 508         struct arphdr _arp;
 509
 510         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
 511                 return FLOW_DISSECT_RET_OUT_GOOD;
 512
 513         arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
 514                                    hlen, &_arp);
 515         if (!arp)
 516                 return FLOW_DISSECT_RET_OUT_BAD;
 517
 518         if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
 519             arp->ar_pro != htons(ETH_P_IP) ||
 520             arp->ar_hln != ETH_ALEN ||
 521             arp->ar_pln != 4 ||
 522             (arp->ar_op != htons(ARPOP_REPLY) &&
 523              arp->ar_op != htons(ARPOP_REQUEST)))
 524                 return FLOW_DISSECT_RET_OUT_BAD;
 525
 526         arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
 527                                        sizeof(_arp_eth), data,
 528                                        hlen, &_arp_eth);
 529         if (!arp_eth)
 530                 return FLOW_DISSECT_RET_OUT_BAD;
 531
 532         key_arp = skb_flow_dissector_target(flow_dissector,
 533                                             FLOW_DISSECTOR_KEY_ARP,
 534                                             target_container);
 535
 536         memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
 537         memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));
 538
 539         /* Only store the lower byte of the opcode;
 540          * this covers ARPOP_REPLY and ARPOP_REQUEST.
 541          */
 542         key_arp->op = ntohs(arp->ar_op) & 0xff;
 543
 544         ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
 545         ether_addr_copy(key_arp->tha, arp_eth->ar_tha);
 546
 547         return FLOW_DISSECT_RET_OUT_GOOD;
 548 }
 549
 550 static enum flow_dissect_ret
 551 __skb_flow_dissect_gre(const struct sk_buff *skb,
 552                        struct flow_dissector_key_control *key_control,
 553                        struct flow_dissector *flow_dissector,
 554                        void *target_container, const void *data,
 555                        __be16 *p_proto, int *p_nhoff, int *p_hlen,
 556                        unsigned int flags)
 557 {
 558         struct flow_dissector_key_keyid *key_keyid;
 559         struct gre_base_hdr *hdr, _hdr;
 560         int offset = 0;
 561         u16 gre_ver;
 562
 563         hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr),
 564                                    data, *p_hlen, &_hdr);
 565         if (!hdr)
 566                 return FLOW_DISSECT_RET_OUT_BAD;
 567
 568         /* Only look inside GRE without routing */
 569         if (hdr->flags & GRE_ROUTING)
 570                 return FLOW_DISSECT_RET_OUT_GOOD;
 571
 572         /* Only look inside GRE for version 0 and 1 */
 573         gre_ver = ntohs(hdr->flags & GRE_VERSION);
 574         if (gre_ver > 1)
 575                 return FLOW_DISSECT_RET_OUT_GOOD;
 576
 577         *p_proto = hdr->protocol;
 578         if (gre_ver) {
 579                 /* Version1 must be PPTP, and check the flags */
 580                 if (!(*p_proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
 581                         return FLOW_DISSECT_RET_OUT_GOOD;
 582         }
 583
 584         offset += sizeof(struct gre_base_hdr);
 585
 586         if (hdr->flags & GRE_CSUM)
 587                 offset += sizeof_field(struct gre_full_hdr, csum) +
 588                           sizeof_field(struct gre_full_hdr, reserved1);
 589
 590         if (hdr->flags & GRE_KEY) {
 591                 const __be32 *keyid;
 592                 __be32 _keyid;
 593
 594                 keyid = __skb_header_pointer(skb, *p_nhoff + offset,
 595                                              sizeof(_keyid),
 596                                              data, *p_hlen, &_keyid);
 597                 if (!keyid)
 598                         return FLOW_DISSECT_RET_OUT_BAD;
 599
 600                 if (dissector_uses_key(flow_dissector,
 601                                        FLOW_DISSECTOR_KEY_GRE_KEYID)) {
 602                         key_keyid = skb_flow_dissector_target(flow_dissector,
 603                                                               FLOW_DISSECTOR_KEY_GRE_KEYID,
 604                                                               target_container);
 605                         if (gre_ver == 0)
 606                                 key_keyid->keyid = *keyid;
 607                         else
 608                                 key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
 609                 }
 610                 offset += sizeof_field(struct gre_full_hdr, key);
 611         }
 612
 613         if (hdr->flags & GRE_SEQ)
 614                 offset += sizeof_field(struct pptp_gre_header, seq);
 615
 616         if (gre_ver == 0) {
 617                 if (*p_proto == htons(ETH_P_TEB)) {
 618                         const struct ethhdr *eth;
 619                         struct ethhdr _eth;
 620
 621                         eth = __skb_header_pointer(skb, *p_nhoff + offset,
 622                                                    sizeof(_eth),
 623                                                    data, *p_hlen, &_eth);
 624                         if (!eth)
 625                                 return FLOW_DISSECT_RET_OUT_BAD;
 626                         *p_proto = eth->h_proto;
 627                         offset += sizeof(*eth);
 628
 629                         /* Cap headers that we access via pointers at the
 630                          * end of the Ethernet header as our maximum alignment
 631                          * at that point is only 2 bytes.
 632                          */
 633                         if (NET_IP_ALIGN)
 634                                 *p_hlen = *p_nhoff + offset;
 635                 }
 636         } else { /* version 1, must be PPTP */
 637                 u8 _ppp_hdr[PPP_HDRLEN];
 638                 u8 *ppp_hdr;
 639
 640                 if (hdr->flags & GRE_ACK)
 641                         offset += sizeof_field(struct pptp_gre_header, ack);
 642
 643                 ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
 644                                                sizeof(_ppp_hdr),
 645                                                data, *p_hlen, _ppp_hdr);
 646                 if (!ppp_hdr)
 647                         return FLOW_DISSECT_RET_OUT_BAD;
 648
 649                 switch (PPP_PROTOCOL(ppp_hdr)) {
 650                 case PPP_IP:
 651                         *p_proto = htons(ETH_P_IP);
 652                         break;
 653                 case PPP_IPV6:
 654                         *p_proto = htons(ETH_P_IPV6);
 655                         break;
 656                 default:
 657                         /* Could probably catch some more like MPLS */
 658                         break;
 659                 }
 660
 661                 offset += PPP_HDRLEN;
 662         }
 663
 664         *p_nhoff += offset;
 665         key_control->flags |= FLOW_DIS_ENCAPSULATION;
 666         if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
 667                 return FLOW_DISSECT_RET_OUT_GOOD;
 668
 669         return FLOW_DISSECT_RET_PROTO_AGAIN;
 670 }
 671
 672 /**
 673  * __skb_flow_dissect_batadv() - dissect batman-adv header
 674  * @skb: sk_buff to with the batman-adv header
 675  * @key_control: flow dissectors control key
 676  * @data: raw buffer pointer to the packet, if NULL use skb->data
 677  * @p_proto: pointer used to update the protocol to process next
 678  * @p_nhoff: pointer used to update inner network header offset
 679  * @hlen: packet header length
 680  * @flags: any combination of FLOW_DISSECTOR_F_*
 681  *
 682  * ETH_P_BATMAN packets are tried to be dissected. Only
 683  * &struct batadv_unicast packets are actually processed because they contain an
 684  * inner ethernet header and are usually followed by actual network header. This
 685  * allows the flow dissector to continue processing the packet.
 686  *
 687  * Return: FLOW_DISSECT_RET_PROTO_AGAIN when &struct batadv_unicast was found,
 688  *  FLOW_DISSECT_RET_OUT_GOOD when dissector should stop after encapsulation,
 689  *  otherwise FLOW_DISSECT_RET_OUT_BAD
 690  */
 691 static enum flow_dissect_ret
 692 __skb_flow_dissect_batadv(const struct sk_buff *skb,
 693                           struct flow_dissector_key_control *key_control,
 694                           const void *data, __be16 *p_proto, int *p_nhoff,
 695                           int hlen, unsigned int flags)
 696 {
 697         struct {
 698                 struct batadv_unicast_packet batadv_unicast;
 699                 struct ethhdr eth;
 700         } *hdr, _hdr;
 701
 702         hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr), data, hlen,
 703                                    &_hdr);
 704         if (!hdr)
 705                 return FLOW_DISSECT_RET_OUT_BAD;
 706
 707         if (hdr->batadv_unicast.version != BATADV_COMPAT_VERSION)
 708                 return FLOW_DISSECT_RET_OUT_BAD;
 709
 710         if (hdr->batadv_unicast.packet_type != BATADV_UNICAST)
 711                 return FLOW_DISSECT_RET_OUT_BAD;
 712
 713         *p_proto = hdr->eth.h_proto;
 714         *p_nhoff += sizeof(*hdr);
 715
 716         key_control->flags |= FLOW_DIS_ENCAPSULATION;
 717         if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
 718                 return FLOW_DISSECT_RET_OUT_GOOD;
 719
 720         return FLOW_DISSECT_RET_PROTO_AGAIN;
 721 }
 722
 723 static void
 724 __skb_flow_dissect_tcp(const struct sk_buff *skb,
 725                        struct flow_dissector *flow_dissector,
 726                        void *target_container, const void *data,
 727                        int thoff, int hlen)
 728 {
 729         struct flow_dissector_key_tcp *key_tcp;
 730         struct tcphdr *th, _th;
 731
 732         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_TCP))
 733                 return;
 734
 735         th = __skb_header_pointer(skb, thoff, sizeof(_th), data, hlen, &_th);
 736         if (!th)
 737                 return;
 738
 739         if (unlikely(__tcp_hdrlen(th) < sizeof(_th)))
 740                 return;
 741
 742         key_tcp = skb_flow_dissector_target(flow_dissector,
 743                                             FLOW_DISSECTOR_KEY_TCP,
 744                                             target_container);
 745         key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF));
 746 }
 747
 748 static void
 749 __skb_flow_dissect_ports(const struct sk_buff *skb,
 750                          struct flow_dissector *flow_dissector,
 751                          void *target_container, const void *data,
 752                          int nhoff, u8 ip_proto, int hlen)
 753 {
 754         enum flow_dissector_key_id dissector_ports = FLOW_DISSECTOR_KEY_MAX;
 755         struct flow_dissector_key_ports *key_ports;
 756
 757         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS))
 758                 dissector_ports = FLOW_DISSECTOR_KEY_PORTS;
 759         else if (dissector_uses_key(flow_dissector,
 760                                     FLOW_DISSECTOR_KEY_PORTS_RANGE))
 761                 dissector_ports = FLOW_DISSECTOR_KEY_PORTS_RANGE;
 762
 763         if (dissector_ports == FLOW_DISSECTOR_KEY_MAX)
 764                 return;
 765
 766         key_ports = skb_flow_dissector_target(flow_dissector,
 767                                               dissector_ports,
 768                                               target_container);
 769         key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
 770                                                 data, hlen);
 771 }
 772
 773 static void
 774 __skb_flow_dissect_ipv4(const struct sk_buff *skb,
 775                         struct flow_dissector *flow_dissector,
 776                         void *target_container, const void *data,
 777                         const struct iphdr *iph)
 778 {
 779         struct flow_dissector_key_ip *key_ip;
 780
 781         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
 782                 return;
 783
 784         key_ip = skb_flow_dissector_target(flow_dissector,
 785                                            FLOW_DISSECTOR_KEY_IP,
 786                                            target_container);
 787         key_ip->tos = iph->tos;
 788         key_ip->ttl = iph->ttl;
 789 }
 790
 791 static void
 792 __skb_flow_dissect_ipv6(const struct sk_buff *skb,
 793                         struct flow_dissector *flow_dissector,
 794                         void *target_container, const void *data,
 795                         const struct ipv6hdr *iph)
 796 {
 797         struct flow_dissector_key_ip *key_ip;
 798
 799         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
 800                 return;
 801
 802         key_ip = skb_flow_dissector_target(flow_dissector,
 803                                            FLOW_DISSECTOR_KEY_IP,
 804                                            target_container);
 805         key_ip->tos = ipv6_get_dsfield(iph);
 806         key_ip->ttl = iph->hop_limit;
 807 }
 808
 809 /* Maximum number of protocol headers that can be parsed in
 810  * __skb_flow_dissect
 811  */
 812 #define MAX_FLOW_DISSECT_HDRS   15
 813
 814 static bool skb_flow_dissect_allowed(int *num_hdrs)
 815 {
 816         ++*num_hdrs;
 817
 818         return (*num_hdrs <= MAX_FLOW_DISSECT_HDRS);
 819 }
 820
 821 static void __skb_flow_bpf_to_target(const struct bpf_flow_keys *flow_keys,
 822                                      struct flow_dissector *flow_dissector,
 823                                      void *target_container)
 824 {
 825         struct flow_dissector_key_ports *key_ports = NULL;
 826         struct flow_dissector_key_control *key_control;
 827         struct flow_dissector_key_basic *key_basic;
 828         struct flow_dissector_key_addrs *key_addrs;
 829         struct flow_dissector_key_tags *key_tags;
 830
 831         key_control = skb_flow_dissector_target(flow_dissector,
 832                                                 FLOW_DISSECTOR_KEY_CONTROL,
 833                                                 target_container);
 834         key_control->thoff = flow_keys->thoff;
 835         if (flow_keys->is_frag)
 836                 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
 837         if (flow_keys->is_first_frag)
 838                 key_control->flags |= FLOW_DIS_FIRST_FRAG;
 839         if (flow_keys->is_encap)
 840                 key_control->flags |= FLOW_DIS_ENCAPSULATION;
 841
 842         key_basic = skb_flow_dissector_target(flow_dissector,
 843                                               FLOW_DISSECTOR_KEY_BASIC,
 844                                               target_container);
 845         key_basic->n_proto = flow_keys->n_proto;
 846         key_basic->ip_proto = flow_keys->ip_proto;
 847
 848         if (flow_keys->addr_proto == ETH_P_IP &&
 849             dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
 850                 key_addrs = skb_flow_dissector_target(flow_dissector,
 851                                                       FLOW_DISSECTOR_KEY_IPV4_ADDRS,
 852                                                       target_container);
 853                 key_addrs->v4addrs.src = flow_keys->ipv4_src;
 854                 key_addrs->v4addrs.dst = flow_keys->ipv4_dst;
 855                 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
 856         } else if (flow_keys->addr_proto == ETH_P_IPV6 &&
 857                    dissector_uses_key(flow_dissector,
 858                                       FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
 859                 key_addrs = skb_flow_dissector_target(flow_dissector,
 860                                                       FLOW_DISSECTOR_KEY_IPV6_ADDRS,
 861                                                       target_container);
 862                 memcpy(&key_addrs->v6addrs.src, &flow_keys->ipv6_src,
 863                        sizeof(key_addrs->v6addrs.src));
 864                 memcpy(&key_addrs->v6addrs.dst, &flow_keys->ipv6_dst,
 865                        sizeof(key_addrs->v6addrs.dst));
 866                 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
 867         }
 868
 869         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS))
 870                 key_ports = skb_flow_dissector_target(flow_dissector,
 871                                                       FLOW_DISSECTOR_KEY_PORTS,
 872                                                       target_container);
 873         else if (dissector_uses_key(flow_dissector,
 874                                     FLOW_DISSECTOR_KEY_PORTS_RANGE))
 875                 key_ports = skb_flow_dissector_target(flow_dissector,
 876                                                       FLOW_DISSECTOR_KEY_PORTS_RANGE,
 877                                                       target_container);
 878
 879         if (key_ports) {
 880                 key_ports->src = flow_keys->sport;
 881                 key_ports->dst = flow_keys->dport;
 882         }
 883
 884         if (dissector_uses_key(flow_dissector,
 885                                FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
 886                 key_tags = skb_flow_dissector_target(flow_dissector,
 887                                                      FLOW_DISSECTOR_KEY_FLOW_LABEL,
 888                                                      target_container);
 889                 key_tags->flow_label = ntohl(flow_keys->flow_label);
 890         }
 891 }
 892
 893 u32 bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
 894                      __be16 proto, int nhoff, int hlen, unsigned int flags)
 895 {
 896         struct bpf_flow_keys *flow_keys = ctx->flow_keys;
 897         u32 result;
 898
 899         /* Pass parameters to the BPF program */
 900         memset(flow_keys, 0, sizeof(*flow_keys));
 901         flow_keys->n_proto = proto;
 902         flow_keys->nhoff = nhoff;
 903         flow_keys->thoff = flow_keys->nhoff;
 904
 905         BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG !=
 906                      (int)FLOW_DISSECTOR_F_PARSE_1ST_FRAG);
 907         BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL !=
 908                      (int)FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
 909         BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP !=
 910                      (int)FLOW_DISSECTOR_F_STOP_AT_ENCAP);
 911         flow_keys->flags = flags;
 912
 913         result = bpf_prog_run_pin_on_cpu(prog, ctx);
 914
 915         flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen);
 916         flow_keys->thoff = clamp_t(u16, flow_keys->thoff,
 917                                    flow_keys->nhoff, hlen);
 918
 919         return result;
 920 }
 921
 922 static bool is_pppoe_ses_hdr_valid(const struct pppoe_hdr *hdr)
 923 {
 924         return hdr->ver == 1 && hdr->type == 1 && hdr->code == 0;
 925 }
 926
 927 /**
 928  * __skb_flow_dissect - extract the flow_keys struct and return it
 929  * @net: associated network namespace, derived from @skb if NULL
 930  * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
 931  * @flow_dissector: list of keys to dissect
 932  * @target_container: target structure to put dissected values into
 933  * @data: raw buffer pointer to the packet, if NULL use skb->data
 934  * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
 935  * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
 936  * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
 937  * @flags: flags that control the dissection process, e.g.
 938  *         FLOW_DISSECTOR_F_STOP_AT_ENCAP.
 939  *
 940  * The function will try to retrieve individual keys into target specified
 941  * by flow_dissector from either the skbuff or a raw buffer specified by the
 942  * rest parameters.
 943  *
 944  * Caller must take care of zeroing target container memory.
 945  */
 946 bool __skb_flow_dissect(const struct net *net,
 947                         const struct sk_buff *skb,
 948                         struct flow_dissector *flow_dissector,
 949                         void *target_container, const void *data,
 950                         __be16 proto, int nhoff, int hlen, unsigned int flags)
 951 {
 952         struct flow_dissector_key_control *key_control;
 953         struct flow_dissector_key_basic *key_basic;
 954         struct flow_dissector_key_addrs *key_addrs;
 955         struct flow_dissector_key_tags *key_tags;
 956         struct flow_dissector_key_vlan *key_vlan;
 957         enum flow_dissect_ret fdret;
 958         enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX;
 959         bool mpls_el = false;
 960         int mpls_lse = 0;
 961         int num_hdrs = 0;
 962         u8 ip_proto = 0;
 963         bool ret;
 964
 965         if (!data) {
 966                 data = skb->data;
 967                 proto = skb_vlan_tag_present(skb) ?
 968                          skb->vlan_proto : skb->protocol;
 969                 nhoff = skb_network_offset(skb);
 970                 hlen = skb_headlen(skb);
 971 #if IS_ENABLED(CONFIG_NET_DSA)
 972                 if (unlikely(skb->dev && netdev_uses_dsa(skb->dev) &&
 973                              proto == htons(ETH_P_XDSA))) {
 974                         const struct dsa_device_ops *ops;
 975                         int offset = 0;
 976
 977                         ops = skb->dev->dsa_ptr->tag_ops;
 978                         /* Only DSA header taggers break flow dissection */
 979                         if (ops->needed_headroom) {
 980                                 if (ops->flow_dissect)
 981                                         ops->flow_dissect(skb, &proto, &offset);
 982                                 else
 983                                         dsa_tag_generic_flow_dissect(skb,
 984                                                                      &proto,
 985                                                                      &offset);
 986                                 hlen -= offset;
 987                                 nhoff += offset;
 988                         }
 989                 }
 990 #endif
 991         }
 992
 993         /* It is ensured by skb_flow_dissector_init() that control key will
 994          * be always present.
 995          */
 996         key_control = skb_flow_dissector_target(flow_dissector,
 997                                                 FLOW_DISSECTOR_KEY_CONTROL,
 998                                                 target_container);
 999
1000         /* It is ensured by skb_flow_dissector_init() that basic key will
1001          * be always present.
1002          */
1003         key_basic = skb_flow_dissector_target(flow_dissector,
1004                                               FLOW_DISSECTOR_KEY_BASIC,
1005                                               target_container);
1006
1007         if (skb) {
1008                 if (!net) {
1009                         if (skb->dev)
1010                                 net = dev_net(skb->dev);
1011                         else if (skb->sk)
1012                                 net = sock_net(skb->sk);
1013                 }
1014         }
1015
1016         WARN_ON_ONCE(!net);
1017         if (net) {
1018                 enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;
1019                 struct bpf_prog_array *run_array;
1020
1021                 rcu_read_lock();
1022                 run_array = rcu_dereference(init_net.bpf.run_array[type]);
1023                 if (!run_array)
1024                         run_array = rcu_dereference(net->bpf.run_array[type]);
1025
1026                 if (run_array) {
1027                         struct bpf_flow_keys flow_keys;
1028                         struct bpf_flow_dissector ctx = {
1029                                 .flow_keys = &flow_keys,
1030                                 .data = data,
1031                                 .data_end = data + hlen,
1032                         };
1033                         __be16 n_proto = proto;
1034                         struct bpf_prog *prog;
1035                         u32 result;
1036
1037                         if (skb) {
1038                                 ctx.skb = skb;
1039                                 /* we can't use 'proto' in the skb case
1040                                  * because it might be set to skb->vlan_proto
1041                                  * which has been pulled from the data
1042                                  */
1043                                 n_proto = skb->protocol;
1044                         }
1045
1046                         prog = READ_ONCE(run_array->items[0].prog);
1047                         result = bpf_flow_dissect(prog, &ctx, n_proto, nhoff,
1048                                                   hlen, flags);
1049                         if (result == BPF_FLOW_DISSECTOR_CONTINUE)
1050                                 goto dissect_continue;
1051                         __skb_flow_bpf_to_target(&flow_keys, flow_dissector,
1052                                                  target_container);
1053                         rcu_read_unlock();
1054                         return result == BPF_OK;
1055                 }
1056 dissect_continue:
1057                 rcu_read_unlock();
1058         }
1059
1060         if (dissector_uses_key(flow_dissector,
1061                                FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
1062                 struct ethhdr *eth = eth_hdr(skb);
1063                 struct flow_dissector_key_eth_addrs *key_eth_addrs;
1064
1065                 key_eth_addrs = skb_flow_dissector_target(flow_dissector,
1066                                                           FLOW_DISSECTOR_KEY_ETH_ADDRS,
1067                                                           target_container);
1068                 memcpy(key_eth_addrs, eth, sizeof(*key_eth_addrs));
1069         }
1070
1071         if (dissector_uses_key(flow_dissector,
1072                                FLOW_DISSECTOR_KEY_NUM_OF_VLANS)) {
1073                 struct flow_dissector_key_num_of_vlans *key_num_of_vlans;
1074
1075                 key_num_of_vlans = skb_flow_dissector_target(flow_dissector,
1076                                                              FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
1077                                                              target_container);
1078                 key_num_of_vlans->num_of_vlans = 0;
1079         }
1080
1081 proto_again:
1082         fdret = FLOW_DISSECT_RET_CONTINUE;
1083
1084         switch (proto) {
1085         case htons(ETH_P_IP): {
1086                 const struct iphdr *iph;
1087                 struct iphdr _iph;
1088
1089                 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
1090                 if (!iph || iph->ihl < 5) {
1091                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1092                         break;
1093                 }
1094
1095                 nhoff += iph->ihl * 4;
1096
1097                 ip_proto = iph->protocol;
1098
1099                 if (dissector_uses_key(flow_dissector,
1100                                        FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
1101                         key_addrs = skb_flow_dissector_target(flow_dissector,
1102                                                               FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1103                                                               target_container);
1104
1105                         memcpy(&key_addrs->v4addrs.src, &iph->saddr,
1106                                sizeof(key_addrs->v4addrs.src));
1107                         memcpy(&key_addrs->v4addrs.dst, &iph->daddr,
1108                                sizeof(key_addrs->v4addrs.dst));
1109                         key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
1110                 }
1111
1112                 __skb_flow_dissect_ipv4(skb, flow_dissector,
1113                                         target_container, data, iph);
1114
1115                 if (ip_is_fragment(iph)) {
1116                         key_control->flags |= FLOW_DIS_IS_FRAGMENT;
1117
1118                         if (iph->frag_off & htons(IP_OFFSET)) {
1119                                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1120                                 break;
1121                         } else {
1122                                 key_control->flags |= FLOW_DIS_FIRST_FRAG;
1123                                 if (!(flags &
1124                                       FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
1125                                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1126                                         break;
1127                                 }
1128                         }
1129                 }
1130
1131                 break;
1132         }
1133         case htons(ETH_P_IPV6): {
1134                 const struct ipv6hdr *iph;
1135                 struct ipv6hdr _iph;
1136
1137                 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
1138                 if (!iph) {
1139                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1140                         break;
1141                 }
1142
1143                 ip_proto = iph->nexthdr;
1144                 nhoff += sizeof(struct ipv6hdr);
1145
1146                 if (dissector_uses_key(flow_dissector,
1147                                        FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
1148                         key_addrs = skb_flow_dissector_target(flow_dissector,
1149                                                               FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1150                                                               target_container);
1151
1152                         memcpy(&key_addrs->v6addrs.src, &iph->saddr,
1153                                sizeof(key_addrs->v6addrs.src));
1154                         memcpy(&key_addrs->v6addrs.dst, &iph->daddr,
1155                                sizeof(key_addrs->v6addrs.dst));
1156                         key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1157                 }
1158
1159                 if ((dissector_uses_key(flow_dissector,
1160                                         FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
1161                      (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
1162                     ip6_flowlabel(iph)) {
1163                         __be32 flow_label = ip6_flowlabel(iph);
1164
1165                         if (dissector_uses_key(flow_dissector,
1166                                                FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
1167                                 key_tags = skb_flow_dissector_target(flow_dissector,
1168                                                                      FLOW_DISSECTOR_KEY_FLOW_LABEL,
1169                                                                      target_container);
1170                                 key_tags->flow_label = ntohl(flow_label);
1171                         }
1172                         if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
1173                                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1174                                 break;
1175                         }
1176                 }
1177
1178                 __skb_flow_dissect_ipv6(skb, flow_dissector,
1179                                         target_container, data, iph);
1180
1181                 break;
1182         }
1183         case htons(ETH_P_8021AD):
1184         case htons(ETH_P_8021Q): {
1185                 const struct vlan_hdr *vlan = NULL;
1186                 struct vlan_hdr _vlan;
1187                 __be16 saved_vlan_tpid = proto;
1188
1189                 if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX &&
1190                     skb && skb_vlan_tag_present(skb)) {
1191                         proto = skb->protocol;
1192                 } else {
1193                         vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
1194                                                     data, hlen, &_vlan);
1195                         if (!vlan) {
1196                                 fdret = FLOW_DISSECT_RET_OUT_BAD;
1197                                 break;
1198                         }
1199
1200                         proto = vlan->h_vlan_encapsulated_proto;
1201                         nhoff += sizeof(*vlan);
1202                 }
1203
1204                 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_NUM_OF_VLANS) &&
1205                     !(key_control->flags & FLOW_DIS_ENCAPSULATION)) {
1206                         struct flow_dissector_key_num_of_vlans *key_nvs;
1207
1208                         key_nvs = skb_flow_dissector_target(flow_dissector,
1209                                                             FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
1210                                                             target_container);
1211                         key_nvs->num_of_vlans++;
1212                 }
1213
1214                 if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX) {
1215                         dissector_vlan = FLOW_DISSECTOR_KEY_VLAN;
1216                 } else if (dissector_vlan == FLOW_DISSECTOR_KEY_VLAN) {
1217                         dissector_vlan = FLOW_DISSECTOR_KEY_CVLAN;
1218                 } else {
1219                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1220                         break;
1221                 }
1222
1223                 if (dissector_uses_key(flow_dissector, dissector_vlan)) {
1224                         key_vlan = skb_flow_dissector_target(flow_dissector,
1225                                                              dissector_vlan,
1226                                                              target_container);
1227
1228                         if (!vlan) {
1229                                 key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
1230                                 key_vlan->vlan_priority = skb_vlan_tag_get_prio(skb);
1231                         } else {
1232                                 key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
1233                                         VLAN_VID_MASK;
1234                                 key_vlan->vlan_priority =
1235                                         (ntohs(vlan->h_vlan_TCI) &
1236                                          VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
1237                         }
1238                         key_vlan->vlan_tpid = saved_vlan_tpid;
1239                         key_vlan->vlan_eth_type = proto;
1240                 }
1241
1242                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1243                 break;
1244         }
1245         case htons(ETH_P_PPP_SES): {
1246                 struct {
1247                         struct pppoe_hdr hdr;
1248                         __be16 proto;
1249                 } *hdr, _hdr;
1250                 u16 ppp_proto;
1251
1252                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
1253                 if (!hdr) {
1254                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1255                         break;
1256                 }
1257
1258                 if (!is_pppoe_ses_hdr_valid(&hdr->hdr)) {
1259                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1260                         break;
1261                 }
1262
1263                 /* least significant bit of the most significant octet
1264                  * indicates if protocol field was compressed
1265                  */
1266                 ppp_proto = ntohs(hdr->proto);
1267                 if (ppp_proto & 0x0100) {
1268                         ppp_proto = ppp_proto >> 8;
1269                         nhoff += PPPOE_SES_HLEN - 1;
1270                 } else {
1271                         nhoff += PPPOE_SES_HLEN;
1272                 }
1273
1274                 if (ppp_proto == PPP_IP) {
1275                         proto = htons(ETH_P_IP);
1276                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1277                 } else if (ppp_proto == PPP_IPV6) {
1278                         proto = htons(ETH_P_IPV6);
1279                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1280                 } else if (ppp_proto == PPP_MPLS_UC) {
1281                         proto = htons(ETH_P_MPLS_UC);
1282                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1283                 } else if (ppp_proto == PPP_MPLS_MC) {
1284                         proto = htons(ETH_P_MPLS_MC);
1285                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1286                 } else if (ppp_proto_is_valid(ppp_proto)) {
1287                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1288                 } else {
1289                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1290                         break;
1291                 }
1292
1293                 if (dissector_uses_key(flow_dissector,
1294                                        FLOW_DISSECTOR_KEY_PPPOE)) {
1295                         struct flow_dissector_key_pppoe *key_pppoe;
1296
1297                         key_pppoe = skb_flow_dissector_target(flow_dissector,
1298                                                               FLOW_DISSECTOR_KEY_PPPOE,
1299                                                               target_container);
1300                         key_pppoe->session_id = hdr->hdr.sid;
1301                         key_pppoe->ppp_proto = htons(ppp_proto);
1302                         key_pppoe->type = htons(ETH_P_PPP_SES);
1303                 }
1304                 break;
1305         }
1306         case htons(ETH_P_TIPC): {
1307                 struct tipc_basic_hdr *hdr, _hdr;
1308
1309                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
1310                                            data, hlen, &_hdr);
1311                 if (!hdr) {
1312                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1313                         break;
1314                 }
1315
1316                 if (dissector_uses_key(flow_dissector,
1317                                        FLOW_DISSECTOR_KEY_TIPC)) {
1318                         key_addrs = skb_flow_dissector_target(flow_dissector,
1319                                                               FLOW_DISSECTOR_KEY_TIPC,
1320                                                               target_container);
1321                         key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
1322                         key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
1323                 }
1324                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1325                 break;
1326         }
1327
1328         case htons(ETH_P_MPLS_UC):
1329         case htons(ETH_P_MPLS_MC):
1330                 fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
1331                                                 target_container, data,
1332                                                 nhoff, hlen, mpls_lse,
1333                                                 &mpls_el);
1334                 nhoff += sizeof(struct mpls_label);
1335                 mpls_lse++;
1336                 break;
1337         case htons(ETH_P_FCOE):
1338                 if ((hlen - nhoff) < FCOE_HEADER_LEN) {
1339                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1340                         break;
1341                 }
1342
1343                 nhoff += FCOE_HEADER_LEN;
1344                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1345                 break;
1346
1347         case htons(ETH_P_ARP):
1348         case htons(ETH_P_RARP):
1349                 fdret = __skb_flow_dissect_arp(skb, flow_dissector,
1350                                                target_container, data,
1351                                                nhoff, hlen);
1352                 break;
1353
1354         case htons(ETH_P_BATMAN):
1355                 fdret = __skb_flow_dissect_batadv(skb, key_control, data,
1356                                                   &proto, &nhoff, hlen, flags);
1357                 break;
1358
1359         case htons(ETH_P_1588): {
1360                 struct ptp_header *hdr, _hdr;
1361
1362                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
1363                                            hlen, &_hdr);
1364                 if (!hdr) {
1365                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1366                         break;
1367                 }
1368
1369                 nhoff += sizeof(struct ptp_header);
1370                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1371                 break;
1372         }
1373
1374         case htons(ETH_P_PRP):
1375         case htons(ETH_P_HSR): {
1376                 struct hsr_tag *hdr, _hdr;
1377
1378                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen,
1379                                            &_hdr);
1380                 if (!hdr) {
1381                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1382                         break;
1383                 }
1384
1385                 proto = hdr->encap_proto;
1386                 nhoff += HSR_HLEN;
1387                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1388                 break;
1389         }
1390
1391         default:
1392                 fdret = FLOW_DISSECT_RET_OUT_BAD;
1393                 break;
1394         }
1395
1396         /* Process result of proto processing */
1397         switch (fdret) {
1398         case FLOW_DISSECT_RET_OUT_GOOD:
1399                 goto out_good;
1400         case FLOW_DISSECT_RET_PROTO_AGAIN:
1401                 if (skb_flow_dissect_allowed(&num_hdrs))
1402                         goto proto_again;
1403                 goto out_good;
1404         case FLOW_DISSECT_RET_CONTINUE:
1405         case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1406                 break;
1407         case FLOW_DISSECT_RET_OUT_BAD:
1408         default:
1409                 goto out_bad;
1410         }
1411
1412 ip_proto_again:
1413         fdret = FLOW_DISSECT_RET_CONTINUE;
1414
1415         switch (ip_proto) {
1416         case IPPROTO_GRE:
1417                 if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1418                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1419                         break;
1420                 }
1421
1422                 fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
1423                                                target_container, data,
1424                                                &proto, &nhoff, &hlen, flags);
1425                 break;
1426
1427         case NEXTHDR_HOP:
1428         case NEXTHDR_ROUTING:
1429         case NEXTHDR_DEST: {
1430                 u8 _opthdr[2], *opthdr;
1431
1432                 if (proto != htons(ETH_P_IPV6))
1433                         break;
1434
1435                 opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
1436                                               data, hlen, &_opthdr);
1437                 if (!opthdr) {
1438                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1439                         break;
1440                 }
1441
1442                 ip_proto = opthdr[0];
1443                 nhoff += (opthdr[1] + 1) << 3;
1444
1445                 fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
1446                 break;
1447         }
1448         case NEXTHDR_FRAGMENT: {
1449                 struct frag_hdr _fh, *fh;
1450
1451                 if (proto != htons(ETH_P_IPV6))
1452                         break;
1453
1454                 fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
1455                                           data, hlen, &_fh);
1456
1457                 if (!fh) {
1458                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1459                         break;
1460                 }
1461
1462                 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
1463
1464                 nhoff += sizeof(_fh);
1465                 ip_proto = fh->nexthdr;
1466
1467                 if (!(fh->frag_off & htons(IP6_OFFSET))) {
1468                         key_control->flags |= FLOW_DIS_FIRST_FRAG;
1469                         if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
1470                                 fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
1471                                 break;
1472                         }
1473                 }
1474
1475                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1476                 break;
1477         }
1478         case IPPROTO_IPIP:
1479                 if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1480                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1481                         break;
1482                 }
1483
1484                 proto = htons(ETH_P_IP);
1485
1486                 key_control->flags |= FLOW_DIS_ENCAPSULATION;
1487                 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
1488                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1489                         break;
1490                 }
1491
1492                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1493                 break;
1494
1495         case IPPROTO_IPV6:
1496                 if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1497                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1498                         break;
1499                 }
1500
1501                 proto = htons(ETH_P_IPV6);
1502
1503                 key_control->flags |= FLOW_DIS_ENCAPSULATION;
1504                 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
1505                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1506                         break;
1507                 }
1508
1509                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1510                 break;
1511
1512
1513         case IPPROTO_MPLS:
1514                 proto = htons(ETH_P_MPLS_UC);
1515                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1516                 break;
1517
1518         case IPPROTO_TCP:
1519                 __skb_flow_dissect_tcp(skb, flow_dissector, target_container,
1520                                        data, nhoff, hlen);
1521                 break;
1522
1523         case IPPROTO_ICMP:
1524         case IPPROTO_ICMPV6:
1525                 __skb_flow_dissect_icmp(skb, flow_dissector, target_container,
1526                                         data, nhoff, hlen);
1527                 break;
1528         case IPPROTO_L2TP:
1529                 __skb_flow_dissect_l2tpv3(skb, flow_dissector, target_container,
1530                                           data, nhoff, hlen);
1531                 break;
1532
1533         default:
1534                 break;
1535         }
1536
1537         if (!(key_control->flags & FLOW_DIS_IS_FRAGMENT))
1538                 __skb_flow_dissect_ports(skb, flow_dissector, target_container,
1539                                          data, nhoff, ip_proto, hlen);
1540
1541         /* Process result of IP proto processing */
1542         switch (fdret) {
1543         case FLOW_DISSECT_RET_PROTO_AGAIN:
1544                 if (skb_flow_dissect_allowed(&num_hdrs))
1545                         goto proto_again;
1546                 break;
1547         case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1548                 if (skb_flow_dissect_allowed(&num_hdrs))
1549                         goto ip_proto_again;
1550                 break;
1551         case FLOW_DISSECT_RET_OUT_GOOD:
1552         case FLOW_DISSECT_RET_CONTINUE:
1553                 break;
1554         case FLOW_DISSECT_RET_OUT_BAD:
1555         default:
1556                 goto out_bad;
1557         }
1558
1559 out_good:
1560         ret = true;
1561
1562 out:
1563         key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
1564         key_basic->n_proto = proto;
1565         key_basic->ip_proto = ip_proto;
1566
1567         return ret;
1568
1569 out_bad:
1570         ret = false;
1571         goto out;
1572 }
1573 EXPORT_SYMBOL(__skb_flow_dissect);
1574
1575 static siphash_aligned_key_t hashrnd;
1576 static __always_inline void __flow_hash_secret_init(void)
1577 {
1578         net_get_random_once(&hashrnd, sizeof(hashrnd));
1579 }
1580
1581 static const void *flow_keys_hash_start(const struct flow_keys *flow)
1582 {
1583         BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % SIPHASH_ALIGNMENT);
1584         return &flow->FLOW_KEYS_HASH_START_FIELD;
1585 }
1586
1587 static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
1588 {
1589         size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
1590
1591         BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
1592
1593         switch (flow->control.addr_type) {
1594         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1595                 diff -= sizeof(flow->addrs.v4addrs);
1596                 break;
1597         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1598                 diff -= sizeof(flow->addrs.v6addrs);
1599                 break;
1600         case FLOW_DISSECTOR_KEY_TIPC:
1601                 diff -= sizeof(flow->addrs.tipckey);
1602                 break;
1603         }
1604         return sizeof(*flow) - diff;
1605 }
1606
1607 __be32 flow_get_u32_src(const struct flow_keys *flow)
1608 {
1609         switch (flow->control.addr_type) {
1610         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1611                 return flow->addrs.v4addrs.src;
1612         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1613                 return (__force __be32)ipv6_addr_hash(
1614                         &flow->addrs.v6addrs.src);
1615         case FLOW_DISSECTOR_KEY_TIPC:
1616                 return flow->addrs.tipckey.key;
1617         default:
1618                 return 0;
1619         }
1620 }
1621 EXPORT_SYMBOL(flow_get_u32_src);
1622
1623 __be32 flow_get_u32_dst(const struct flow_keys *flow)
1624 {
1625         switch (flow->control.addr_type) {
1626         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1627                 return flow->addrs.v4addrs.dst;
1628         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1629                 return (__force __be32)ipv6_addr_hash(
1630                         &flow->addrs.v6addrs.dst);
1631         default:
1632                 return 0;
1633         }
1634 }
1635 EXPORT_SYMBOL(flow_get_u32_dst);
1636
1637 /* Sort the source and destination IP and the ports,
1638  * to have consistent hash within the two directions
1639  */
1640 static inline void __flow_hash_consistentify(struct flow_keys *keys)
1641 {
1642         int addr_diff, i;
1643
1644         switch (keys->control.addr_type) {
1645         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1646                 if ((__force u32)keys->addrs.v4addrs.dst <
1647                     (__force u32)keys->addrs.v4addrs.src)
1648                         swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
1649
1650                 if ((__force u16)keys->ports.dst <
1651                     (__force u16)keys->ports.src) {
1652                         swap(keys->ports.src, keys->ports.dst);
1653                 }
1654                 break;
1655         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1656                 addr_diff = memcmp(&keys->addrs.v6addrs.dst,
1657                                    &keys->addrs.v6addrs.src,
1658                                    sizeof(keys->addrs.v6addrs.dst));
1659                 if (addr_diff < 0) {
1660                         for (i = 0; i < 4; i++)
1661                                 swap(keys->addrs.v6addrs.src.s6_addr32[i],
1662                                      keys->addrs.v6addrs.dst.s6_addr32[i]);
1663                 }
1664                 if ((__force u16)keys->ports.dst <
1665                     (__force u16)keys->ports.src) {
1666                         swap(keys->ports.src, keys->ports.dst);
1667                 }
1668                 break;
1669         }
1670 }
1671
1672 static inline u32 __flow_hash_from_keys(struct flow_keys *keys,
1673                                         const siphash_key_t *keyval)
1674 {
1675         u32 hash;
1676
1677         __flow_hash_consistentify(keys);
1678
1679         hash = siphash(flow_keys_hash_start(keys),
1680                        flow_keys_hash_length(keys), keyval);
1681         if (!hash)
1682                 hash = 1;
1683
1684         return hash;
1685 }
1686
1687 u32 flow_hash_from_keys(struct flow_keys *keys)
1688 {
1689         __flow_hash_secret_init();
1690         return __flow_hash_from_keys(keys, &hashrnd);
1691 }
1692 EXPORT_SYMBOL(flow_hash_from_keys);
1693
1694 static inline u32 ___skb_get_hash(const struct sk_buff *skb,
1695                                   struct flow_keys *keys,
1696                                   const siphash_key_t *keyval)
1697 {
1698         skb_flow_dissect_flow_keys(skb, keys,
1699                                    FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1700
1701         return __flow_hash_from_keys(keys, keyval);
1702 }
1703
1704 struct _flow_keys_digest_data {
1705         __be16  n_proto;
1706         u8      ip_proto;
1707         u8      padding;
1708         __be32  ports;
1709         __be32  src;
1710         __be32  dst;
1711 };
1712
1713 void make_flow_keys_digest(struct flow_keys_digest *digest,
1714                            const struct flow_keys *flow)
1715 {
1716         struct _flow_keys_digest_data *data =
1717             (struct _flow_keys_digest_data *)digest;
1718
1719         BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));
1720
1721         memset(digest, 0, sizeof(*digest));
1722
1723         data->n_proto = flow->basic.n_proto;
1724         data->ip_proto = flow->basic.ip_proto;
1725         data->ports = flow->ports.ports;
1726         data->src = flow->addrs.v4addrs.src;
1727         data->dst = flow->addrs.v4addrs.dst;
1728 }
1729 EXPORT_SYMBOL(make_flow_keys_digest);
1730
1731 static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
1732
1733 u32 __skb_get_hash_symmetric(const struct sk_buff *skb)
1734 {
1735         struct flow_keys keys;
1736
1737         __flow_hash_secret_init();
1738
1739         memset(&keys, 0, sizeof(keys));
1740         __skb_flow_dissect(NULL, skb, &flow_keys_dissector_symmetric,
1741                            &keys, NULL, 0, 0, 0, 0);
1742
1743         return __flow_hash_from_keys(&keys, &hashrnd);
1744 }
1745 EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric);
1746
1747 /**
1748  * __skb_get_hash: calculate a flow hash
1749  * @skb: sk_buff to calculate flow hash from
1750  *
1751  * This function calculates a flow hash based on src/dst addresses
1752  * and src/dst port numbers.  Sets hash in skb to non-zero hash value
1753  * on success, zero indicates no valid hash.  Also, sets l4_hash in skb
1754  * if hash is a canonical 4-tuple hash over transport ports.
1755  */
1756 void __skb_get_hash(struct sk_buff *skb)
1757 {
1758         struct flow_keys keys;
1759         u32 hash;
1760
1761         __flow_hash_secret_init();
1762
1763         hash = ___skb_get_hash(skb, &keys, &hashrnd);
1764
1765         __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
1766 }
1767 EXPORT_SYMBOL(__skb_get_hash);
1768
1769 __u32 skb_get_hash_perturb(const struct sk_buff *skb,
1770                            const siphash_key_t *perturb)
1771 {
1772         struct flow_keys keys;
1773
1774         return ___skb_get_hash(skb, &keys, perturb);
1775 }
1776 EXPORT_SYMBOL(skb_get_hash_perturb);
1777
1778 u32 __skb_get_poff(const struct sk_buff *skb, const void *data,
1779                    const struct flow_keys_basic *keys, int hlen)
1780 {
1781         u32 poff = keys->control.thoff;
1782
1783         /* skip L4 headers for fragments after the first */
1784         if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
1785             !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
1786                 return poff;
1787
1788         switch (keys->basic.ip_proto) {
1789         case IPPROTO_TCP: {
1790                 /* access doff as u8 to avoid unaligned access */
1791                 const u8 *doff;
1792                 u8 _doff;
1793
1794                 doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
1795                                             data, hlen, &_doff);
1796                 if (!doff)
1797                         return poff;
1798
1799                 poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
1800                 break;
1801         }
1802         case IPPROTO_UDP:
1803         case IPPROTO_UDPLITE:
1804                 poff += sizeof(struct udphdr);
1805                 break;
1806         /* For the rest, we do not really care about header
1807          * extensions at this point for now.
1808          */
1809         case IPPROTO_ICMP:
1810                 poff += sizeof(struct icmphdr);
1811                 break;
1812         case IPPROTO_ICMPV6:
1813                 poff += sizeof(struct icmp6hdr);
1814                 break;
1815         case IPPROTO_IGMP:
1816                 poff += sizeof(struct igmphdr);
1817                 break;
1818         case IPPROTO_DCCP:
1819                 poff += sizeof(struct dccp_hdr);
1820                 break;
1821         case IPPROTO_SCTP:
1822                 poff += sizeof(struct sctphdr);
1823                 break;
1824         }
1825
1826         return poff;
1827 }
1828
1829 /**
1830  * skb_get_poff - get the offset to the payload
1831  * @skb: sk_buff to get the payload offset from
1832  *
1833  * The function will get the offset to the payload as far as it could
1834  * be dissected.  The main user is currently BPF, so that we can dynamically
1835  * truncate packets without needing to push actual payload to the user
1836  * space and can analyze headers only, instead.
1837  */
1838 u32 skb_get_poff(const struct sk_buff *skb)
1839 {
1840         struct flow_keys_basic keys;
1841
1842         if (!skb_flow_dissect_flow_keys_basic(NULL, skb, &keys,
1843                                               NULL, 0, 0, 0, 0))
1844                 return 0;
1845
1846         return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
1847 }
1848
1849 __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
1850 {
1851         memset(keys, 0, sizeof(*keys));
1852
1853         memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
1854             sizeof(keys->addrs.v6addrs.src));
1855         memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
1856             sizeof(keys->addrs.v6addrs.dst));
1857         keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1858         keys->ports.src = fl6->fl6_sport;
1859         keys->ports.dst = fl6->fl6_dport;
1860         keys->keyid.keyid = fl6->fl6_gre_key;
1861         keys->tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
1862         keys->basic.ip_proto = fl6->flowi6_proto;
1863
1864         return flow_hash_from_keys(keys);
1865 }
1866 EXPORT_SYMBOL(__get_hash_from_flowi6);
1867
1868 static const struct flow_dissector_key flow_keys_dissector_keys[] = {
1869         {
1870                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1871                 .offset = offsetof(struct flow_keys, control),
1872         },
1873         {
1874                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1875                 .offset = offsetof(struct flow_keys, basic),
1876         },
1877         {
1878                 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1879                 .offset = offsetof(struct flow_keys, addrs.v4addrs),
1880         },
1881         {
1882                 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1883                 .offset = offsetof(struct flow_keys, addrs.v6addrs),
1884         },
1885         {
1886                 .key_id = FLOW_DISSECTOR_KEY_TIPC,
1887                 .offset = offsetof(struct flow_keys, addrs.tipckey),
1888         },
1889         {
1890                 .key_id = FLOW_DISSECTOR_KEY_PORTS,
1891                 .offset = offsetof(struct flow_keys, ports),
1892         },
1893         {
1894                 .key_id = FLOW_DISSECTOR_KEY_VLAN,
1895                 .offset = offsetof(struct flow_keys, vlan),
1896         },
1897         {
1898                 .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
1899                 .offset = offsetof(struct flow_keys, tags),
1900         },
1901         {
1902                 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
1903                 .offset = offsetof(struct flow_keys, keyid),
1904         },
1905 };
1906
1907 static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
1908         {
1909                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1910                 .offset = offsetof(struct flow_keys, control),
1911         },
1912         {
1913                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1914                 .offset = offsetof(struct flow_keys, basic),
1915         },
1916         {
1917                 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1918                 .offset = offsetof(struct flow_keys, addrs.v4addrs),
1919         },
1920         {
1921                 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1922                 .offset = offsetof(struct flow_keys, addrs.v6addrs),
1923         },
1924         {
1925                 .key_id = FLOW_DISSECTOR_KEY_PORTS,
1926                 .offset = offsetof(struct flow_keys, ports),
1927         },
1928 };
1929
1930 static const struct flow_dissector_key flow_keys_basic_dissector_keys[] = {
1931         {
1932                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1933                 .offset = offsetof(struct flow_keys, control),
1934         },
1935         {
1936                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1937                 .offset = offsetof(struct flow_keys, basic),
1938         },
1939 };
1940
1941 struct flow_dissector flow_keys_dissector __read_mostly;
1942 EXPORT_SYMBOL(flow_keys_dissector);
1943
1944 struct flow_dissector flow_keys_basic_dissector __read_mostly;
1945 EXPORT_SYMBOL(flow_keys_basic_dissector);
1946
1947 static int __init init_default_flow_dissectors(void)
1948 {
1949         skb_flow_dissector_init(&flow_keys_dissector,
1950                                 flow_keys_dissector_keys,
1951                                 ARRAY_SIZE(flow_keys_dissector_keys));
1952         skb_flow_dissector_init(&flow_keys_dissector_symmetric,
1953                                 flow_keys_dissector_symmetric_keys,
1954                                 ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
1955         skb_flow_dissector_init(&flow_keys_basic_dissector,
1956                                 flow_keys_basic_dissector_keys,
1957                                 ARRAY_SIZE(flow_keys_basic_dissector_keys));
1958         return 0;
1959 }
1960 core_initcall(init_default_flow_dissectors);