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