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 <net/pkt_cls.h>
  31 #include <scsi/fc/fc_fcoe.h>
  32 #include <uapi/linux/batadv_packet.h>
  33 #include <linux/bpf.h>
  34 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
  35 #include <net/netfilter/nf_conntrack_core.h>
  36 #include <net/netfilter/nf_conntrack_labels.h>
  37 #endif
  38 #include <linux/bpf-netns.h>
  39
  40 static void dissector_set_key(struct flow_dissector *flow_dissector,
  41                               enum flow_dissector_key_id key_id)
  42 {
  43         flow_dissector->used_keys |= (1 << key_id);
  44 }
  45
  46 void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
  47                              const struct flow_dissector_key *key,
  48                              unsigned int key_count)
  49 {
  50         unsigned int i;
  51
  52         memset(flow_dissector, 0, sizeof(*flow_dissector));
  53
  54         for (i = 0; i < key_count; i++, key++) {
  55                 /* User should make sure that every key target offset is within
  56                  * boundaries of unsigned short.
  57                  */
  58                 BUG_ON(key->offset > USHRT_MAX);
  59                 BUG_ON(dissector_uses_key(flow_dissector,
  60                                           key->key_id));
  61
  62                 dissector_set_key(flow_dissector, key->key_id);
  63                 flow_dissector->offset[key->key_id] = key->offset;
  64         }
  65
  66         /* Ensure that the dissector always includes control and basic key.
  67          * That way we are able to avoid handling lack of these in fast path.
  68          */
  69         BUG_ON(!dissector_uses_key(flow_dissector,
  70                                    FLOW_DISSECTOR_KEY_CONTROL));
  71         BUG_ON(!dissector_uses_key(flow_dissector,
  72                                    FLOW_DISSECTOR_KEY_BASIC));
  73 }
  74 EXPORT_SYMBOL(skb_flow_dissector_init);
  75
  76 #ifdef CONFIG_BPF_SYSCALL
  77 int flow_dissector_bpf_prog_attach_check(struct net *net,
  78                                          struct bpf_prog *prog)
  79 {
  80         enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;
  81
  82         if (net == &init_net) {
  83                 /* BPF flow dissector in the root namespace overrides
  84                  * any per-net-namespace one. When attaching to root,
  85                  * make sure we don't have any BPF program attached
  86                  * to the non-root namespaces.
  87                  */
  88                 struct net *ns;
  89
  90                 for_each_net(ns) {
  91                         if (ns == &init_net)
  92                                 continue;
  93                         if (rcu_access_pointer(ns->bpf.run_array[type]))
  94                                 return -EEXIST;
  95                 }
  96         } else {
  97                 /* Make sure root flow dissector is not attached
  98                  * when attaching to the non-root namespace.
  99                  */
 100                 if (rcu_access_pointer(init_net.bpf.run_array[type]))
 101                         return -EEXIST;
 102         }
 103
 104         return 0;
 105 }
 106 #endif /* CONFIG_BPF_SYSCALL */
 107
 108 /**
 109  * __skb_flow_get_ports - extract the upper layer ports and return them
 110  * @skb: sk_buff to extract the ports from
 111  * @thoff: transport header offset
 112  * @ip_proto: protocol for which to get port offset
 113  * @data: raw buffer pointer to the packet, if NULL use skb->data
 114  * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
 115  *
 116  * The function will try to retrieve the ports at offset thoff + poff where poff
 117  * is the protocol port offset returned from proto_ports_offset
 118  */
 119 __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
 120                             const void *data, int hlen)
 121 {
 122         int poff = proto_ports_offset(ip_proto);
 123
 124         if (!data) {
 125                 data = skb->data;
 126                 hlen = skb_headlen(skb);
 127         }
 128
 129         if (poff >= 0) {
 130                 __be32 *ports, _ports;
 131
 132                 ports = __skb_header_pointer(skb, thoff + poff,
 133                                              sizeof(_ports), data, hlen, &_ports);
 134                 if (ports)
 135                         return *ports;
 136         }
 137
 138         return 0;
 139 }
 140 EXPORT_SYMBOL(__skb_flow_get_ports);
 141
 142 static bool icmp_has_id(u8 type)
 143 {
 144         switch (type) {
 145         case ICMP_ECHO:
 146         case ICMP_ECHOREPLY:
 147         case ICMP_TIMESTAMP:
 148         case ICMP_TIMESTAMPREPLY:
 149         case ICMPV6_ECHO_REQUEST:
 150         case ICMPV6_ECHO_REPLY:
 151                 return true;
 152         }
 153
 154         return false;
 155 }
 156
 157 /**
 158  * skb_flow_get_icmp_tci - extract ICMP(6) Type, Code and Identifier fields
 159  * @skb: sk_buff to extract from
 160  * @key_icmp: struct flow_dissector_key_icmp to fill
 161  * @data: raw buffer pointer to the packet
 162  * @thoff: offset to extract at
 163  * @hlen: packet header length
 164  */
 165 void skb_flow_get_icmp_tci(const struct sk_buff *skb,
 166                            struct flow_dissector_key_icmp *key_icmp,
 167                            const void *data, int thoff, int hlen)
 168 {
 169         struct icmphdr *ih, _ih;
 170
 171         ih = __skb_header_pointer(skb, thoff, sizeof(_ih), data, hlen, &_ih);
 172         if (!ih)
 173                 return;
 174
 175         key_icmp->type = ih->type;
 176         key_icmp->code = ih->code;
 177
 178         /* As we use 0 to signal that the Id field is not present,
 179          * avoid confusion with packets without such field
 180          */
 181         if (icmp_has_id(ih->type))
 182                 key_icmp->id = ih->un.echo.id ? ntohs(ih->un.echo.id) : 1;
 183         else
 184                 key_icmp->id = 0;
 185 }
 186 EXPORT_SYMBOL(skb_flow_get_icmp_tci);
 187
 188 /* If FLOW_DISSECTOR_KEY_ICMP is set, dissect an ICMP packet
 189  * using skb_flow_get_icmp_tci().
 190  */
 191 static void __skb_flow_dissect_icmp(const struct sk_buff *skb,
 192                                     struct flow_dissector *flow_dissector,
 193                                     void *target_container, const void *data,
 194                                     int thoff, int hlen)
 195 {
 196         struct flow_dissector_key_icmp *key_icmp;
 197
 198         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ICMP))
 199                 return;
 200
 201         key_icmp = skb_flow_dissector_target(flow_dissector,
 202                                              FLOW_DISSECTOR_KEY_ICMP,
 203                                              target_container);
 204
 205         skb_flow_get_icmp_tci(skb, key_icmp, data, thoff, hlen);
 206 }
 207
 208 static void __skb_flow_dissect_l2tpv3(const struct sk_buff *skb,
 209                                       struct flow_dissector *flow_dissector,
 210                                       void *target_container, const void *data,
 211                                       int nhoff, int hlen)
 212 {
 213         struct flow_dissector_key_l2tpv3 *key_l2tpv3;
 214         struct {
 215                 __be32 session_id;
 216         } *hdr, _hdr;
 217
 218         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_L2TPV3))
 219                 return;
 220
 221         hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
 222         if (!hdr)
 223                 return;
 224
 225         key_l2tpv3 = skb_flow_dissector_target(flow_dissector,
 226                                                FLOW_DISSECTOR_KEY_L2TPV3,
 227                                                target_container);
 228
 229         key_l2tpv3->session_id = hdr->session_id;
 230 }
 231
 232 void skb_flow_dissect_meta(const struct sk_buff *skb,
 233                            struct flow_dissector *flow_dissector,
 234                            void *target_container)
 235 {
 236         struct flow_dissector_key_meta *meta;
 237
 238         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_META))
 239                 return;
 240
 241         meta = skb_flow_dissector_target(flow_dissector,
 242                                          FLOW_DISSECTOR_KEY_META,
 243                                          target_container);
 244         meta->ingress_ifindex = skb->skb_iif;
 245 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
 246         if (tc_skb_ext_tc_enabled()) {
 247                 struct tc_skb_ext *ext;
 248
 249                 ext = skb_ext_find(skb, TC_SKB_EXT);
 250                 if (ext)
 251                         meta->l2_miss = ext->l2_miss;
 252         }
 253 #endif
 254 }
 255 EXPORT_SYMBOL(skb_flow_dissect_meta);
 256
 257 static void
 258 skb_flow_dissect_set_enc_addr_type(enum flow_dissector_key_id type,
 259                                    struct flow_dissector *flow_dissector,
 260                                    void *target_container)
 261 {
 262         struct flow_dissector_key_control *ctrl;
 263
 264         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_CONTROL))
 265                 return;
 266
 267         ctrl = skb_flow_dissector_target(flow_dissector,
 268                                          FLOW_DISSECTOR_KEY_ENC_CONTROL,
 269                                          target_container);
 270         ctrl->addr_type = type;
 271 }
 272
 273 void
 274 skb_flow_dissect_ct(const struct sk_buff *skb,
 275                     struct flow_dissector *flow_dissector,
 276                     void *target_container, u16 *ctinfo_map,
 277                     size_t mapsize, bool post_ct, u16 zone)
 278 {
 279 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
 280         struct flow_dissector_key_ct *key;
 281         enum ip_conntrack_info ctinfo;
 282         struct nf_conn_labels *cl;
 283         struct nf_conn *ct;
 284
 285         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_CT))
 286                 return;
 287
 288         ct = nf_ct_get(skb, &ctinfo);
 289         if (!ct && !post_ct)
 290                 return;
 291
 292         key = skb_flow_dissector_target(flow_dissector,
 293                                         FLOW_DISSECTOR_KEY_CT,
 294                                         target_container);
 295
 296         if (!ct) {
 297                 key->ct_state = TCA_FLOWER_KEY_CT_FLAGS_TRACKED |
 298                                 TCA_FLOWER_KEY_CT_FLAGS_INVALID;
 299                 key->ct_zone = zone;
 300                 return;
 301         }
 302
 303         if (ctinfo < mapsize)
 304                 key->ct_state = ctinfo_map[ctinfo];
 305 #if IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)
 306         key->ct_zone = ct->zone.id;
 307 #endif
 308 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 309         key->ct_mark = READ_ONCE(ct->mark);
 310 #endif
 311
 312         cl = nf_ct_labels_find(ct);
 313         if (cl)
 314                 memcpy(key->ct_labels, cl->bits, sizeof(key->ct_labels));
 315 #endif /* CONFIG_NF_CONNTRACK */
 316 }
 317 EXPORT_SYMBOL(skb_flow_dissect_ct);
 318
 319 void
 320 skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
 321                              struct flow_dissector *flow_dissector,
 322                              void *target_container)
 323 {
 324         struct ip_tunnel_info *info;
 325         struct ip_tunnel_key *key;
 326
 327         /* A quick check to see if there might be something to do. */
 328         if (!dissector_uses_key(flow_dissector,
 329                                 FLOW_DISSECTOR_KEY_ENC_KEYID) &&
 330             !dissector_uses_key(flow_dissector,
 331                                 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS) &&
 332             !dissector_uses_key(flow_dissector,
 333                                 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS) &&
 334             !dissector_uses_key(flow_dissector,
 335                                 FLOW_DISSECTOR_KEY_ENC_CONTROL) &&
 336             !dissector_uses_key(flow_dissector,
 337                                 FLOW_DISSECTOR_KEY_ENC_PORTS) &&
 338             !dissector_uses_key(flow_dissector,
 339                                 FLOW_DISSECTOR_KEY_ENC_IP) &&
 340             !dissector_uses_key(flow_dissector,
 341                                 FLOW_DISSECTOR_KEY_ENC_OPTS))
 342                 return;
 343
 344         info = skb_tunnel_info(skb);
 345         if (!info)
 346                 return;
 347
 348         key = &info->key;
 349
 350         switch (ip_tunnel_info_af(info)) {
 351         case AF_INET:
 352                 skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV4_ADDRS,
 353                                                    flow_dissector,
 354                                                    target_container);
 355                 if (dissector_uses_key(flow_dissector,
 356                                        FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS)) {
 357                         struct flow_dissector_key_ipv4_addrs *ipv4;
 358
 359                         ipv4 = skb_flow_dissector_target(flow_dissector,
 360                                                          FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS,
 361                                                          target_container);
 362                         ipv4->src = key->u.ipv4.src;
 363                         ipv4->dst = key->u.ipv4.dst;
 364                 }
 365                 break;
 366         case AF_INET6:
 367                 skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV6_ADDRS,
 368                                                    flow_dissector,
 369                                                    target_container);
 370                 if (dissector_uses_key(flow_dissector,
 371                                        FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS)) {
 372                         struct flow_dissector_key_ipv6_addrs *ipv6;
 373
 374                         ipv6 = skb_flow_dissector_target(flow_dissector,
 375                                                          FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS,
 376                                                          target_container);
 377                         ipv6->src = key->u.ipv6.src;
 378                         ipv6->dst = key->u.ipv6.dst;
 379                 }
 380                 break;
 381         }
 382
 383         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_KEYID)) {
 384                 struct flow_dissector_key_keyid *keyid;
 385
 386                 keyid = skb_flow_dissector_target(flow_dissector,
 387                                                   FLOW_DISSECTOR_KEY_ENC_KEYID,
 388                                                   target_container);
 389                 keyid->keyid = tunnel_id_to_key32(key->tun_id);
 390         }
 391
 392         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_PORTS)) {
 393                 struct flow_dissector_key_ports *tp;
 394
 395                 tp = skb_flow_dissector_target(flow_dissector,
 396                                                FLOW_DISSECTOR_KEY_ENC_PORTS,
 397                                                target_container);
 398                 tp->src = key->tp_src;
 399                 tp->dst = key->tp_dst;
 400         }
 401
 402         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_IP)) {
 403                 struct flow_dissector_key_ip *ip;
 404
 405                 ip = skb_flow_dissector_target(flow_dissector,
 406                                                FLOW_DISSECTOR_KEY_ENC_IP,
 407                                                target_container);
 408                 ip->tos = key->tos;
 409                 ip->ttl = key->ttl;
 410         }
 411
 412         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_OPTS)) {
 413                 struct flow_dissector_key_enc_opts *enc_opt;
 414
 415                 enc_opt = skb_flow_dissector_target(flow_dissector,
 416                                                     FLOW_DISSECTOR_KEY_ENC_OPTS,
 417                                                     target_container);
 418
 419                 if (info->options_len) {
 420                         enc_opt->len = info->options_len;
 421                         ip_tunnel_info_opts_get(enc_opt->data, info);
 422                         enc_opt->dst_opt_type = info->key.tun_flags &
 423                                                 TUNNEL_OPTIONS_PRESENT;
 424                 }
 425         }
 426 }
 427 EXPORT_SYMBOL(skb_flow_dissect_tunnel_info);
 428
 429 void skb_flow_dissect_hash(const struct sk_buff *skb,
 430                            struct flow_dissector *flow_dissector,
 431                            void *target_container)
 432 {
 433         struct flow_dissector_key_hash *key;
 434
 435         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_HASH))
 436                 return;
 437
 438         key = skb_flow_dissector_target(flow_dissector,
 439                                         FLOW_DISSECTOR_KEY_HASH,
 440                                         target_container);
 441
 442         key->hash = skb_get_hash_raw(skb);
 443 }
 444 EXPORT_SYMBOL(skb_flow_dissect_hash);
 445
 446 static enum flow_dissect_ret
 447 __skb_flow_dissect_mpls(const struct sk_buff *skb,
 448                         struct flow_dissector *flow_dissector,
 449                         void *target_container, const void *data, int nhoff,
 450                         int hlen, int lse_index, bool *entropy_label)
 451 {
 452         struct mpls_label *hdr, _hdr;
 453         u32 entry, label, bos;
 454
 455         if (!dissector_uses_key(flow_dissector,
 456                                 FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
 457             !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
 458                 return FLOW_DISSECT_RET_OUT_GOOD;
 459
 460         if (lse_index >= FLOW_DIS_MPLS_MAX)
 461                 return FLOW_DISSECT_RET_OUT_GOOD;
 462
 463         hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
 464                                    hlen, &_hdr);
 465         if (!hdr)
 466                 return FLOW_DISSECT_RET_OUT_BAD;
 467
 468         entry = ntohl(hdr->entry);
 469         label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
 470         bos = (entry & MPLS_LS_S_MASK) >> MPLS_LS_S_SHIFT;
 471
 472         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
 473                 struct flow_dissector_key_mpls *key_mpls;
 474                 struct flow_dissector_mpls_lse *lse;
 475
 476                 key_mpls = skb_flow_dissector_target(flow_dissector,
 477                                                      FLOW_DISSECTOR_KEY_MPLS,
 478                                                      target_container);
 479                 lse = &key_mpls->ls[lse_index];
 480
 481                 lse->mpls_ttl = (entry & MPLS_LS_TTL_MASK) >> MPLS_LS_TTL_SHIFT;
 482                 lse->mpls_bos = bos;
 483                 lse->mpls_tc = (entry & MPLS_LS_TC_MASK) >> MPLS_LS_TC_SHIFT;
 484                 lse->mpls_label = label;
 485                 dissector_set_mpls_lse(key_mpls, lse_index);
 486         }
 487
 488         if (*entropy_label &&
 489             dissector_uses_key(flow_dissector,
 490                                FLOW_DISSECTOR_KEY_MPLS_ENTROPY)) {
 491                 struct flow_dissector_key_keyid *key_keyid;
 492
 493                 key_keyid = skb_flow_dissector_target(flow_dissector,
 494                                                       FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
 495                                                       target_container);
 496                 key_keyid->keyid = cpu_to_be32(label);
 497         }
 498
 499         *entropy_label = label == MPLS_LABEL_ENTROPY;
 500
 501         return bos ? FLOW_DISSECT_RET_OUT_GOOD : FLOW_DISSECT_RET_PROTO_AGAIN;
 502 }
 503
 504 static enum flow_dissect_ret
 505 __skb_flow_dissect_arp(const struct sk_buff *skb,
 506                        struct flow_dissector *flow_dissector,
 507                        void *target_container, const void *data,
 508                        int nhoff, int hlen)
 509 {
 510         struct flow_dissector_key_arp *key_arp;
 511         struct {
 512                 unsigned char ar_sha[ETH_ALEN];
 513                 unsigned char ar_sip[4];
 514                 unsigned char ar_tha[ETH_ALEN];
 515                 unsigned char ar_tip[4];
 516         } *arp_eth, _arp_eth;
 517         const struct arphdr *arp;
 518         struct arphdr _arp;
 519
 520         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
 521                 return FLOW_DISSECT_RET_OUT_GOOD;
 522
 523         arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
 524                                    hlen, &_arp);
 525         if (!arp)
 526                 return FLOW_DISSECT_RET_OUT_BAD;
 527
 528         if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
 529             arp->ar_pro != htons(ETH_P_IP) ||
 530             arp->ar_hln != ETH_ALEN ||
 531             arp->ar_pln != 4 ||
 532             (arp->ar_op != htons(ARPOP_REPLY) &&
 533              arp->ar_op != htons(ARPOP_REQUEST)))
 534                 return FLOW_DISSECT_RET_OUT_BAD;
 535
 536         arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
 537                                        sizeof(_arp_eth), data,
 538                                        hlen, &_arp_eth);
 539         if (!arp_eth)
 540                 return FLOW_DISSECT_RET_OUT_BAD;
 541
 542         key_arp = skb_flow_dissector_target(flow_dissector,
 543                                             FLOW_DISSECTOR_KEY_ARP,
 544                                             target_container);
 545
 546         memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
 547         memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));
 548
 549         /* Only store the lower byte of the opcode;
 550          * this covers ARPOP_REPLY and ARPOP_REQUEST.
 551          */
 552         key_arp->op = ntohs(arp->ar_op) & 0xff;
 553
 554         ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
 555         ether_addr_copy(key_arp->tha, arp_eth->ar_tha);
 556
 557         return FLOW_DISSECT_RET_OUT_GOOD;
 558 }
 559
 560 static enum flow_dissect_ret
 561 __skb_flow_dissect_cfm(const struct sk_buff *skb,
 562                        struct flow_dissector *flow_dissector,
 563                        void *target_container, const void *data,
 564                        int nhoff, int hlen)
 565 {
 566         struct flow_dissector_key_cfm *key, *hdr, _hdr;
 567
 568         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_CFM))
 569                 return FLOW_DISSECT_RET_OUT_GOOD;
 570
 571         hdr = __skb_header_pointer(skb, nhoff, sizeof(*key), data, hlen, &_hdr);
 572         if (!hdr)
 573                 return FLOW_DISSECT_RET_OUT_BAD;
 574
 575         key = skb_flow_dissector_target(flow_dissector, FLOW_DISSECTOR_KEY_CFM,
 576                                         target_container);
 577
 578         key->mdl_ver = hdr->mdl_ver;
 579         key->opcode = hdr->opcode;
 580
 581         return FLOW_DISSECT_RET_OUT_GOOD;
 582 }
 583
 584 static enum flow_dissect_ret
 585 __skb_flow_dissect_gre(const struct sk_buff *skb,
 586                        struct flow_dissector_key_control *key_control,
 587                        struct flow_dissector *flow_dissector,
 588                        void *target_container, const void *data,
 589                        __be16 *p_proto, int *p_nhoff, int *p_hlen,
 590                        unsigned int flags)
 591 {
 592         struct flow_dissector_key_keyid *key_keyid;
 593         struct gre_base_hdr *hdr, _hdr;
 594         int offset = 0;
 595         u16 gre_ver;
 596
 597         hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr),
 598                                    data, *p_hlen, &_hdr);
 599         if (!hdr)
 600                 return FLOW_DISSECT_RET_OUT_BAD;
 601
 602         /* Only look inside GRE without routing */
 603         if (hdr->flags & GRE_ROUTING)
 604                 return FLOW_DISSECT_RET_OUT_GOOD;
 605
 606         /* Only look inside GRE for version 0 and 1 */
 607         gre_ver = ntohs(hdr->flags & GRE_VERSION);
 608         if (gre_ver > 1)
 609                 return FLOW_DISSECT_RET_OUT_GOOD;
 610
 611         *p_proto = hdr->protocol;
 612         if (gre_ver) {
 613                 /* Version1 must be PPTP, and check the flags */
 614                 if (!(*p_proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
 615                         return FLOW_DISSECT_RET_OUT_GOOD;
 616         }
 617
 618         offset += sizeof(struct gre_base_hdr);
 619
 620         if (hdr->flags & GRE_CSUM)
 621                 offset += sizeof_field(struct gre_full_hdr, csum) +
 622                           sizeof_field(struct gre_full_hdr, reserved1);
 623
 624         if (hdr->flags & GRE_KEY) {
 625                 const __be32 *keyid;
 626                 __be32 _keyid;
 627
 628                 keyid = __skb_header_pointer(skb, *p_nhoff + offset,
 629                                              sizeof(_keyid),
 630                                              data, *p_hlen, &_keyid);
 631                 if (!keyid)
 632                         return FLOW_DISSECT_RET_OUT_BAD;
 633
 634                 if (dissector_uses_key(flow_dissector,
 635                                        FLOW_DISSECTOR_KEY_GRE_KEYID)) {
 636                         key_keyid = skb_flow_dissector_target(flow_dissector,
 637                                                               FLOW_DISSECTOR_KEY_GRE_KEYID,
 638                                                               target_container);
 639                         if (gre_ver == 0)
 640                                 key_keyid->keyid = *keyid;
 641                         else
 642                                 key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
 643                 }
 644                 offset += sizeof_field(struct gre_full_hdr, key);
 645         }
 646
 647         if (hdr->flags & GRE_SEQ)
 648                 offset += sizeof_field(struct pptp_gre_header, seq);
 649
 650         if (gre_ver == 0) {
 651                 if (*p_proto == htons(ETH_P_TEB)) {
 652                         const struct ethhdr *eth;
 653                         struct ethhdr _eth;
 654
 655                         eth = __skb_header_pointer(skb, *p_nhoff + offset,
 656                                                    sizeof(_eth),
 657                                                    data, *p_hlen, &_eth);
 658                         if (!eth)
 659                                 return FLOW_DISSECT_RET_OUT_BAD;
 660                         *p_proto = eth->h_proto;
 661                         offset += sizeof(*eth);
 662
 663                         /* Cap headers that we access via pointers at the
 664                          * end of the Ethernet header as our maximum alignment
 665                          * at that point is only 2 bytes.
 666                          */
 667                         if (NET_IP_ALIGN)
 668                                 *p_hlen = *p_nhoff + offset;
 669                 }
 670         } else { /* version 1, must be PPTP */
 671                 u8 _ppp_hdr[PPP_HDRLEN];
 672                 u8 *ppp_hdr;
 673
 674                 if (hdr->flags & GRE_ACK)
 675                         offset += sizeof_field(struct pptp_gre_header, ack);
 676
 677                 ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
 678                                                sizeof(_ppp_hdr),
 679                                                data, *p_hlen, _ppp_hdr);
 680                 if (!ppp_hdr)
 681                         return FLOW_DISSECT_RET_OUT_BAD;
 682
 683                 switch (PPP_PROTOCOL(ppp_hdr)) {
 684                 case PPP_IP:
 685                         *p_proto = htons(ETH_P_IP);
 686                         break;
 687                 case PPP_IPV6:
 688                         *p_proto = htons(ETH_P_IPV6);
 689                         break;
 690                 default:
 691                         /* Could probably catch some more like MPLS */
 692                         break;
 693                 }
 694
 695                 offset += PPP_HDRLEN;
 696         }
 697
 698         *p_nhoff += offset;
 699         key_control->flags |= FLOW_DIS_ENCAPSULATION;
 700         if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
 701                 return FLOW_DISSECT_RET_OUT_GOOD;
 702
 703         return FLOW_DISSECT_RET_PROTO_AGAIN;
 704 }
 705
 706 /**
 707  * __skb_flow_dissect_batadv() - dissect batman-adv header
 708  * @skb: sk_buff to with the batman-adv header
 709  * @key_control: flow dissectors control key
 710  * @data: raw buffer pointer to the packet, if NULL use skb->data
 711  * @p_proto: pointer used to update the protocol to process next
 712  * @p_nhoff: pointer used to update inner network header offset
 713  * @hlen: packet header length
 714  * @flags: any combination of FLOW_DISSECTOR_F_*
 715  *
 716  * ETH_P_BATMAN packets are tried to be dissected. Only
 717  * &struct batadv_unicast packets are actually processed because they contain an
 718  * inner ethernet header and are usually followed by actual network header. This
 719  * allows the flow dissector to continue processing the packet.
 720  *
 721  * Return: FLOW_DISSECT_RET_PROTO_AGAIN when &struct batadv_unicast was found,
 722  *  FLOW_DISSECT_RET_OUT_GOOD when dissector should stop after encapsulation,
 723  *  otherwise FLOW_DISSECT_RET_OUT_BAD
 724  */
 725 static enum flow_dissect_ret
 726 __skb_flow_dissect_batadv(const struct sk_buff *skb,
 727                           struct flow_dissector_key_control *key_control,
 728                           const void *data, __be16 *p_proto, int *p_nhoff,
 729                           int hlen, unsigned int flags)
 730 {
 731         struct {
 732                 struct batadv_unicast_packet batadv_unicast;
 733                 struct ethhdr eth;
 734         } *hdr, _hdr;
 735
 736         hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr), data, hlen,
 737                                    &_hdr);
 738         if (!hdr)
 739                 return FLOW_DISSECT_RET_OUT_BAD;
 740
 741         if (hdr->batadv_unicast.version != BATADV_COMPAT_VERSION)
 742                 return FLOW_DISSECT_RET_OUT_BAD;
 743
 744         if (hdr->batadv_unicast.packet_type != BATADV_UNICAST)
 745                 return FLOW_DISSECT_RET_OUT_BAD;
 746
 747         *p_proto = hdr->eth.h_proto;
 748         *p_nhoff += sizeof(*hdr);
 749
 750         key_control->flags |= FLOW_DIS_ENCAPSULATION;
 751         if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
 752                 return FLOW_DISSECT_RET_OUT_GOOD;
 753
 754         return FLOW_DISSECT_RET_PROTO_AGAIN;
 755 }
 756
 757 static void
 758 __skb_flow_dissect_tcp(const struct sk_buff *skb,
 759                        struct flow_dissector *flow_dissector,
 760                        void *target_container, const void *data,
 761                        int thoff, int hlen)
 762 {
 763         struct flow_dissector_key_tcp *key_tcp;
 764         struct tcphdr *th, _th;
 765
 766         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_TCP))
 767                 return;
 768
 769         th = __skb_header_pointer(skb, thoff, sizeof(_th), data, hlen, &_th);
 770         if (!th)
 771                 return;
 772
 773         if (unlikely(__tcp_hdrlen(th) < sizeof(_th)))
 774                 return;
 775
 776         key_tcp = skb_flow_dissector_target(flow_dissector,
 777                                             FLOW_DISSECTOR_KEY_TCP,
 778                                             target_container);
 779         key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF));
 780 }
 781
 782 static void
 783 __skb_flow_dissect_ports(const struct sk_buff *skb,
 784                          struct flow_dissector *flow_dissector,
 785                          void *target_container, const void *data,
 786                          int nhoff, u8 ip_proto, int hlen)
 787 {
 788         enum flow_dissector_key_id dissector_ports = FLOW_DISSECTOR_KEY_MAX;
 789         struct flow_dissector_key_ports *key_ports;
 790
 791         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS))
 792                 dissector_ports = FLOW_DISSECTOR_KEY_PORTS;
 793         else if (dissector_uses_key(flow_dissector,
 794                                     FLOW_DISSECTOR_KEY_PORTS_RANGE))
 795                 dissector_ports = FLOW_DISSECTOR_KEY_PORTS_RANGE;
 796
 797         if (dissector_ports == FLOW_DISSECTOR_KEY_MAX)
 798                 return;
 799
 800         key_ports = skb_flow_dissector_target(flow_dissector,
 801                                               dissector_ports,
 802                                               target_container);
 803         key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
 804                                                 data, hlen);
 805 }
 806
 807 static void
 808 __skb_flow_dissect_ipv4(const struct sk_buff *skb,
 809                         struct flow_dissector *flow_dissector,
 810                         void *target_container, const void *data,
 811                         const struct iphdr *iph)
 812 {
 813         struct flow_dissector_key_ip *key_ip;
 814
 815         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
 816                 return;
 817
 818         key_ip = skb_flow_dissector_target(flow_dissector,
 819                                            FLOW_DISSECTOR_KEY_IP,
 820                                            target_container);
 821         key_ip->tos = iph->tos;
 822         key_ip->ttl = iph->ttl;
 823 }
 824
 825 static void
 826 __skb_flow_dissect_ipv6(const struct sk_buff *skb,
 827                         struct flow_dissector *flow_dissector,
 828                         void *target_container, const void *data,
 829                         const struct ipv6hdr *iph)
 830 {
 831         struct flow_dissector_key_ip *key_ip;
 832
 833         if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
 834                 return;
 835
 836         key_ip = skb_flow_dissector_target(flow_dissector,
 837                                            FLOW_DISSECTOR_KEY_IP,
 838                                            target_container);
 839         key_ip->tos = ipv6_get_dsfield(iph);
 840         key_ip->ttl = iph->hop_limit;
 841 }
 842
 843 /* Maximum number of protocol headers that can be parsed in
 844  * __skb_flow_dissect
 845  */
 846 #define MAX_FLOW_DISSECT_HDRS   15
 847
 848 static bool skb_flow_dissect_allowed(int *num_hdrs)
 849 {
 850         ++*num_hdrs;
 851
 852         return (*num_hdrs <= MAX_FLOW_DISSECT_HDRS);
 853 }
 854
 855 static void __skb_flow_bpf_to_target(const struct bpf_flow_keys *flow_keys,
 856                                      struct flow_dissector *flow_dissector,
 857                                      void *target_container)
 858 {
 859         struct flow_dissector_key_ports *key_ports = NULL;
 860         struct flow_dissector_key_control *key_control;
 861         struct flow_dissector_key_basic *key_basic;
 862         struct flow_dissector_key_addrs *key_addrs;
 863         struct flow_dissector_key_tags *key_tags;
 864
 865         key_control = skb_flow_dissector_target(flow_dissector,
 866                                                 FLOW_DISSECTOR_KEY_CONTROL,
 867                                                 target_container);
 868         key_control->thoff = flow_keys->thoff;
 869         if (flow_keys->is_frag)
 870                 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
 871         if (flow_keys->is_first_frag)
 872                 key_control->flags |= FLOW_DIS_FIRST_FRAG;
 873         if (flow_keys->is_encap)
 874                 key_control->flags |= FLOW_DIS_ENCAPSULATION;
 875
 876         key_basic = skb_flow_dissector_target(flow_dissector,
 877                                               FLOW_DISSECTOR_KEY_BASIC,
 878                                               target_container);
 879         key_basic->n_proto = flow_keys->n_proto;
 880         key_basic->ip_proto = flow_keys->ip_proto;
 881
 882         if (flow_keys->addr_proto == ETH_P_IP &&
 883             dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
 884                 key_addrs = skb_flow_dissector_target(flow_dissector,
 885                                                       FLOW_DISSECTOR_KEY_IPV4_ADDRS,
 886                                                       target_container);
 887                 key_addrs->v4addrs.src = flow_keys->ipv4_src;
 888                 key_addrs->v4addrs.dst = flow_keys->ipv4_dst;
 889                 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
 890         } else if (flow_keys->addr_proto == ETH_P_IPV6 &&
 891                    dissector_uses_key(flow_dissector,
 892                                       FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
 893                 key_addrs = skb_flow_dissector_target(flow_dissector,
 894                                                       FLOW_DISSECTOR_KEY_IPV6_ADDRS,
 895                                                       target_container);
 896                 memcpy(&key_addrs->v6addrs.src, &flow_keys->ipv6_src,
 897                        sizeof(key_addrs->v6addrs.src));
 898                 memcpy(&key_addrs->v6addrs.dst, &flow_keys->ipv6_dst,
 899                        sizeof(key_addrs->v6addrs.dst));
 900                 key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
 901         }
 902
 903         if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_PORTS))
 904                 key_ports = skb_flow_dissector_target(flow_dissector,
 905                                                       FLOW_DISSECTOR_KEY_PORTS,
 906                                                       target_container);
 907         else if (dissector_uses_key(flow_dissector,
 908                                     FLOW_DISSECTOR_KEY_PORTS_RANGE))
 909                 key_ports = skb_flow_dissector_target(flow_dissector,
 910                                                       FLOW_DISSECTOR_KEY_PORTS_RANGE,
 911                                                       target_container);
 912
 913         if (key_ports) {
 914                 key_ports->src = flow_keys->sport;
 915                 key_ports->dst = flow_keys->dport;
 916         }
 917
 918         if (dissector_uses_key(flow_dissector,
 919                                FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
 920                 key_tags = skb_flow_dissector_target(flow_dissector,
 921                                                      FLOW_DISSECTOR_KEY_FLOW_LABEL,
 922                                                      target_container);
 923                 key_tags->flow_label = ntohl(flow_keys->flow_label);
 924         }
 925 }
 926
 927 u32 bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
 928                      __be16 proto, int nhoff, int hlen, unsigned int flags)
 929 {
 930         struct bpf_flow_keys *flow_keys = ctx->flow_keys;
 931         u32 result;
 932
 933         /* Pass parameters to the BPF program */
 934         memset(flow_keys, 0, sizeof(*flow_keys));
 935         flow_keys->n_proto = proto;
 936         flow_keys->nhoff = nhoff;
 937         flow_keys->thoff = flow_keys->nhoff;
 938
 939         BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_PARSE_1ST_FRAG !=
 940                      (int)FLOW_DISSECTOR_F_PARSE_1ST_FRAG);
 941         BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL !=
 942                      (int)FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
 943         BUILD_BUG_ON((int)BPF_FLOW_DISSECTOR_F_STOP_AT_ENCAP !=
 944                      (int)FLOW_DISSECTOR_F_STOP_AT_ENCAP);
 945         flow_keys->flags = flags;
 946
 947         result = bpf_prog_run_pin_on_cpu(prog, ctx);
 948
 949         flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen);
 950         flow_keys->thoff = clamp_t(u16, flow_keys->thoff,
 951                                    flow_keys->nhoff, hlen);
 952
 953         return result;
 954 }
 955
 956 static bool is_pppoe_ses_hdr_valid(const struct pppoe_hdr *hdr)
 957 {
 958         return hdr->ver == 1 && hdr->type == 1 && hdr->code == 0;
 959 }
 960
 961 /**
 962  * __skb_flow_dissect - extract the flow_keys struct and return it
 963  * @net: associated network namespace, derived from @skb if NULL
 964  * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
 965  * @flow_dissector: list of keys to dissect
 966  * @target_container: target structure to put dissected values into
 967  * @data: raw buffer pointer to the packet, if NULL use skb->data
 968  * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
 969  * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
 970  * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
 971  * @flags: flags that control the dissection process, e.g.
 972  *         FLOW_DISSECTOR_F_STOP_AT_ENCAP.
 973  *
 974  * The function will try to retrieve individual keys into target specified
 975  * by flow_dissector from either the skbuff or a raw buffer specified by the
 976  * rest parameters.
 977  *
 978  * Caller must take care of zeroing target container memory.
 979  */
 980 bool __skb_flow_dissect(const struct net *net,
 981                         const struct sk_buff *skb,
 982                         struct flow_dissector *flow_dissector,
 983                         void *target_container, const void *data,
 984                         __be16 proto, int nhoff, int hlen, unsigned int flags)
 985 {
 986         struct flow_dissector_key_control *key_control;
 987         struct flow_dissector_key_basic *key_basic;
 988         struct flow_dissector_key_addrs *key_addrs;
 989         struct flow_dissector_key_tags *key_tags;
 990         struct flow_dissector_key_vlan *key_vlan;
 991         enum flow_dissect_ret fdret;
 992         enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX;
 993         bool mpls_el = false;
 994         int mpls_lse = 0;
 995         int num_hdrs = 0;
 996         u8 ip_proto = 0;
 997         bool ret;
 998
 999         if (!data) {
1000                 data = skb->data;
1001                 proto = skb_vlan_tag_present(skb) ?
1002                          skb->vlan_proto : skb->protocol;
1003                 nhoff = skb_network_offset(skb);
1004                 hlen = skb_headlen(skb);
1005 #if IS_ENABLED(CONFIG_NET_DSA)
1006                 if (unlikely(skb->dev && netdev_uses_dsa(skb->dev) &&
1007                              proto == htons(ETH_P_XDSA))) {
1008                         struct metadata_dst *md_dst = skb_metadata_dst(skb);
1009                         const struct dsa_device_ops *ops;
1010                         int offset = 0;
1011
1012                         ops = skb->dev->dsa_ptr->tag_ops;
1013                         /* Only DSA header taggers break flow dissection */
1014                         if (ops->needed_headroom &&
1015                             (!md_dst || md_dst->type != METADATA_HW_PORT_MUX)) {
1016                                 if (ops->flow_dissect)
1017                                         ops->flow_dissect(skb, &proto, &offset);
1018                                 else
1019                                         dsa_tag_generic_flow_dissect(skb,
1020                                                                      &proto,
1021                                                                      &offset);
1022                                 hlen -= offset;
1023                                 nhoff += offset;
1024                         }
1025                 }
1026 #endif
1027         }
1028
1029         /* It is ensured by skb_flow_dissector_init() that control key will
1030          * be always present.
1031          */
1032         key_control = skb_flow_dissector_target(flow_dissector,
1033                                                 FLOW_DISSECTOR_KEY_CONTROL,
1034                                                 target_container);
1035
1036         /* It is ensured by skb_flow_dissector_init() that basic key will
1037          * be always present.
1038          */
1039         key_basic = skb_flow_dissector_target(flow_dissector,
1040                                               FLOW_DISSECTOR_KEY_BASIC,
1041                                               target_container);
1042
1043         if (skb) {
1044                 if (!net) {
1045                         if (skb->dev)
1046                                 net = dev_net(skb->dev);
1047                         else if (skb->sk)
1048                                 net = sock_net(skb->sk);
1049                 }
1050         }
1051
1052         WARN_ON_ONCE(!net);
1053         if (net) {
1054                 enum netns_bpf_attach_type type = NETNS_BPF_FLOW_DISSECTOR;
1055                 struct bpf_prog_array *run_array;
1056
1057                 rcu_read_lock();
1058                 run_array = rcu_dereference(init_net.bpf.run_array[type]);
1059                 if (!run_array)
1060                         run_array = rcu_dereference(net->bpf.run_array[type]);
1061
1062                 if (run_array) {
1063                         struct bpf_flow_keys flow_keys;
1064                         struct bpf_flow_dissector ctx = {
1065                                 .flow_keys = &flow_keys,
1066                                 .data = data,
1067                                 .data_end = data + hlen,
1068                         };
1069                         __be16 n_proto = proto;
1070                         struct bpf_prog *prog;
1071                         u32 result;
1072
1073                         if (skb) {
1074                                 ctx.skb = skb;
1075                                 /* we can't use 'proto' in the skb case
1076                                  * because it might be set to skb->vlan_proto
1077                                  * which has been pulled from the data
1078                                  */
1079                                 n_proto = skb->protocol;
1080                         }
1081
1082                         prog = READ_ONCE(run_array->items[0].prog);
1083                         result = bpf_flow_dissect(prog, &ctx, n_proto, nhoff,
1084                                                   hlen, flags);
1085                         if (result == BPF_FLOW_DISSECTOR_CONTINUE)
1086                                 goto dissect_continue;
1087                         __skb_flow_bpf_to_target(&flow_keys, flow_dissector,
1088                                                  target_container);
1089                         rcu_read_unlock();
1090                         return result == BPF_OK;
1091                 }
1092 dissect_continue:
1093                 rcu_read_unlock();
1094         }
1095
1096         if (dissector_uses_key(flow_dissector,
1097                                FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
1098                 struct ethhdr *eth = eth_hdr(skb);
1099                 struct flow_dissector_key_eth_addrs *key_eth_addrs;
1100
1101                 key_eth_addrs = skb_flow_dissector_target(flow_dissector,
1102                                                           FLOW_DISSECTOR_KEY_ETH_ADDRS,
1103                                                           target_container);
1104                 memcpy(key_eth_addrs, eth, sizeof(*key_eth_addrs));
1105         }
1106
1107         if (dissector_uses_key(flow_dissector,
1108                                FLOW_DISSECTOR_KEY_NUM_OF_VLANS)) {
1109                 struct flow_dissector_key_num_of_vlans *key_num_of_vlans;
1110
1111                 key_num_of_vlans = skb_flow_dissector_target(flow_dissector,
1112                                                              FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
1113                                                              target_container);
1114                 key_num_of_vlans->num_of_vlans = 0;
1115         }
1116
1117 proto_again:
1118         fdret = FLOW_DISSECT_RET_CONTINUE;
1119
1120         switch (proto) {
1121         case htons(ETH_P_IP): {
1122                 const struct iphdr *iph;
1123                 struct iphdr _iph;
1124
1125                 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
1126                 if (!iph || iph->ihl < 5) {
1127                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1128                         break;
1129                 }
1130
1131                 nhoff += iph->ihl * 4;
1132
1133                 ip_proto = iph->protocol;
1134
1135                 if (dissector_uses_key(flow_dissector,
1136                                        FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
1137                         key_addrs = skb_flow_dissector_target(flow_dissector,
1138                                                               FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1139                                                               target_container);
1140
1141                         memcpy(&key_addrs->v4addrs.src, &iph->saddr,
1142                                sizeof(key_addrs->v4addrs.src));
1143                         memcpy(&key_addrs->v4addrs.dst, &iph->daddr,
1144                                sizeof(key_addrs->v4addrs.dst));
1145                         key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
1146                 }
1147
1148                 __skb_flow_dissect_ipv4(skb, flow_dissector,
1149                                         target_container, data, iph);
1150
1151                 if (ip_is_fragment(iph)) {
1152                         key_control->flags |= FLOW_DIS_IS_FRAGMENT;
1153
1154                         if (iph->frag_off & htons(IP_OFFSET)) {
1155                                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1156                                 break;
1157                         } else {
1158                                 key_control->flags |= FLOW_DIS_FIRST_FRAG;
1159                                 if (!(flags &
1160                                       FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
1161                                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1162                                         break;
1163                                 }
1164                         }
1165                 }
1166
1167                 break;
1168         }
1169         case htons(ETH_P_IPV6): {
1170                 const struct ipv6hdr *iph;
1171                 struct ipv6hdr _iph;
1172
1173                 iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
1174                 if (!iph) {
1175                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1176                         break;
1177                 }
1178
1179                 ip_proto = iph->nexthdr;
1180                 nhoff += sizeof(struct ipv6hdr);
1181
1182                 if (dissector_uses_key(flow_dissector,
1183                                        FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
1184                         key_addrs = skb_flow_dissector_target(flow_dissector,
1185                                                               FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1186                                                               target_container);
1187
1188                         memcpy(&key_addrs->v6addrs.src, &iph->saddr,
1189                                sizeof(key_addrs->v6addrs.src));
1190                         memcpy(&key_addrs->v6addrs.dst, &iph->daddr,
1191                                sizeof(key_addrs->v6addrs.dst));
1192                         key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1193                 }
1194
1195                 if ((dissector_uses_key(flow_dissector,
1196                                         FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
1197                      (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
1198                     ip6_flowlabel(iph)) {
1199                         __be32 flow_label = ip6_flowlabel(iph);
1200
1201                         if (dissector_uses_key(flow_dissector,
1202                                                FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
1203                                 key_tags = skb_flow_dissector_target(flow_dissector,
1204                                                                      FLOW_DISSECTOR_KEY_FLOW_LABEL,
1205                                                                      target_container);
1206                                 key_tags->flow_label = ntohl(flow_label);
1207                         }
1208                         if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
1209                                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1210                                 break;
1211                         }
1212                 }
1213
1214                 __skb_flow_dissect_ipv6(skb, flow_dissector,
1215                                         target_container, data, iph);
1216
1217                 break;
1218         }
1219         case htons(ETH_P_8021AD):
1220         case htons(ETH_P_8021Q): {
1221                 const struct vlan_hdr *vlan = NULL;
1222                 struct vlan_hdr _vlan;
1223                 __be16 saved_vlan_tpid = proto;
1224
1225                 if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX &&
1226                     skb && skb_vlan_tag_present(skb)) {
1227                         proto = skb->protocol;
1228                 } else {
1229                         vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
1230                                                     data, hlen, &_vlan);
1231                         if (!vlan) {
1232                                 fdret = FLOW_DISSECT_RET_OUT_BAD;
1233                                 break;
1234                         }
1235
1236                         proto = vlan->h_vlan_encapsulated_proto;
1237                         nhoff += sizeof(*vlan);
1238                 }
1239
1240                 if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_NUM_OF_VLANS) &&
1241                     !(key_control->flags & FLOW_DIS_ENCAPSULATION)) {
1242                         struct flow_dissector_key_num_of_vlans *key_nvs;
1243
1244                         key_nvs = skb_flow_dissector_target(flow_dissector,
1245                                                             FLOW_DISSECTOR_KEY_NUM_OF_VLANS,
1246                                                             target_container);
1247                         key_nvs->num_of_vlans++;
1248                 }
1249
1250                 if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX) {
1251                         dissector_vlan = FLOW_DISSECTOR_KEY_VLAN;
1252                 } else if (dissector_vlan == FLOW_DISSECTOR_KEY_VLAN) {
1253                         dissector_vlan = FLOW_DISSECTOR_KEY_CVLAN;
1254                 } else {
1255                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1256                         break;
1257                 }
1258
1259                 if (dissector_uses_key(flow_dissector, dissector_vlan)) {
1260                         key_vlan = skb_flow_dissector_target(flow_dissector,
1261                                                              dissector_vlan,
1262                                                              target_container);
1263
1264                         if (!vlan) {
1265                                 key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
1266                                 key_vlan->vlan_priority = skb_vlan_tag_get_prio(skb);
1267                         } else {
1268                                 key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
1269                                         VLAN_VID_MASK;
1270                                 key_vlan->vlan_priority =
1271                                         (ntohs(vlan->h_vlan_TCI) &
1272                                          VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
1273                         }
1274                         key_vlan->vlan_tpid = saved_vlan_tpid;
1275                         key_vlan->vlan_eth_type = proto;
1276                 }
1277
1278                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1279                 break;
1280         }
1281         case htons(ETH_P_PPP_SES): {
1282                 struct {
1283                         struct pppoe_hdr hdr;
1284                         __be16 proto;
1285                 } *hdr, _hdr;
1286                 u16 ppp_proto;
1287
1288                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
1289                 if (!hdr) {
1290                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1291                         break;
1292                 }
1293
1294                 if (!is_pppoe_ses_hdr_valid(&hdr->hdr)) {
1295                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1296                         break;
1297                 }
1298
1299                 /* least significant bit of the most significant octet
1300                  * indicates if protocol field was compressed
1301                  */
1302                 ppp_proto = ntohs(hdr->proto);
1303                 if (ppp_proto & 0x0100) {
1304                         ppp_proto = ppp_proto >> 8;
1305                         nhoff += PPPOE_SES_HLEN - 1;
1306                 } else {
1307                         nhoff += PPPOE_SES_HLEN;
1308                 }
1309
1310                 if (ppp_proto == PPP_IP) {
1311                         proto = htons(ETH_P_IP);
1312                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1313                 } else if (ppp_proto == PPP_IPV6) {
1314                         proto = htons(ETH_P_IPV6);
1315                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1316                 } else if (ppp_proto == PPP_MPLS_UC) {
1317                         proto = htons(ETH_P_MPLS_UC);
1318                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1319                 } else if (ppp_proto == PPP_MPLS_MC) {
1320                         proto = htons(ETH_P_MPLS_MC);
1321                         fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1322                 } else if (ppp_proto_is_valid(ppp_proto)) {
1323                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1324                 } else {
1325                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1326                         break;
1327                 }
1328
1329                 if (dissector_uses_key(flow_dissector,
1330                                        FLOW_DISSECTOR_KEY_PPPOE)) {
1331                         struct flow_dissector_key_pppoe *key_pppoe;
1332
1333                         key_pppoe = skb_flow_dissector_target(flow_dissector,
1334                                                               FLOW_DISSECTOR_KEY_PPPOE,
1335                                                               target_container);
1336                         key_pppoe->session_id = hdr->hdr.sid;
1337                         key_pppoe->ppp_proto = htons(ppp_proto);
1338                         key_pppoe->type = htons(ETH_P_PPP_SES);
1339                 }
1340                 break;
1341         }
1342         case htons(ETH_P_TIPC): {
1343                 struct tipc_basic_hdr *hdr, _hdr;
1344
1345                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
1346                                            data, hlen, &_hdr);
1347                 if (!hdr) {
1348                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1349                         break;
1350                 }
1351
1352                 if (dissector_uses_key(flow_dissector,
1353                                        FLOW_DISSECTOR_KEY_TIPC)) {
1354                         key_addrs = skb_flow_dissector_target(flow_dissector,
1355                                                               FLOW_DISSECTOR_KEY_TIPC,
1356                                                               target_container);
1357                         key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
1358                         key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
1359                 }
1360                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1361                 break;
1362         }
1363
1364         case htons(ETH_P_MPLS_UC):
1365         case htons(ETH_P_MPLS_MC):
1366                 fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
1367                                                 target_container, data,
1368                                                 nhoff, hlen, mpls_lse,
1369                                                 &mpls_el);
1370                 nhoff += sizeof(struct mpls_label);
1371                 mpls_lse++;
1372                 break;
1373         case htons(ETH_P_FCOE):
1374                 if ((hlen - nhoff) < FCOE_HEADER_LEN) {
1375                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1376                         break;
1377                 }
1378
1379                 nhoff += FCOE_HEADER_LEN;
1380                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1381                 break;
1382
1383         case htons(ETH_P_ARP):
1384         case htons(ETH_P_RARP):
1385                 fdret = __skb_flow_dissect_arp(skb, flow_dissector,
1386                                                target_container, data,
1387                                                nhoff, hlen);
1388                 break;
1389
1390         case htons(ETH_P_BATMAN):
1391                 fdret = __skb_flow_dissect_batadv(skb, key_control, data,
1392                                                   &proto, &nhoff, hlen, flags);
1393                 break;
1394
1395         case htons(ETH_P_1588): {
1396                 struct ptp_header *hdr, _hdr;
1397
1398                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
1399                                            hlen, &_hdr);
1400                 if (!hdr) {
1401                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1402                         break;
1403                 }
1404
1405                 nhoff += ntohs(hdr->message_length);
1406                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1407                 break;
1408         }
1409
1410         case htons(ETH_P_PRP):
1411         case htons(ETH_P_HSR): {
1412                 struct hsr_tag *hdr, _hdr;
1413
1414                 hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen,
1415                                            &_hdr);
1416                 if (!hdr) {
1417                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1418                         break;
1419                 }
1420
1421                 proto = hdr->encap_proto;
1422                 nhoff += HSR_HLEN;
1423                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1424                 break;
1425         }
1426
1427         case htons(ETH_P_CFM):
1428                 fdret = __skb_flow_dissect_cfm(skb, flow_dissector,
1429                                                target_container, data,
1430                                                nhoff, hlen);
1431                 break;
1432
1433         default:
1434                 fdret = FLOW_DISSECT_RET_OUT_BAD;
1435                 break;
1436         }
1437
1438         /* Process result of proto processing */
1439         switch (fdret) {
1440         case FLOW_DISSECT_RET_OUT_GOOD:
1441                 goto out_good;
1442         case FLOW_DISSECT_RET_PROTO_AGAIN:
1443                 if (skb_flow_dissect_allowed(&num_hdrs))
1444                         goto proto_again;
1445                 goto out_good;
1446         case FLOW_DISSECT_RET_CONTINUE:
1447         case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1448                 break;
1449         case FLOW_DISSECT_RET_OUT_BAD:
1450         default:
1451                 goto out_bad;
1452         }
1453
1454 ip_proto_again:
1455         fdret = FLOW_DISSECT_RET_CONTINUE;
1456
1457         switch (ip_proto) {
1458         case IPPROTO_GRE:
1459                 if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1460                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1461                         break;
1462                 }
1463
1464                 fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
1465                                                target_container, data,
1466                                                &proto, &nhoff, &hlen, flags);
1467                 break;
1468
1469         case NEXTHDR_HOP:
1470         case NEXTHDR_ROUTING:
1471         case NEXTHDR_DEST: {
1472                 u8 _opthdr[2], *opthdr;
1473
1474                 if (proto != htons(ETH_P_IPV6))
1475                         break;
1476
1477                 opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
1478                                               data, hlen, &_opthdr);
1479                 if (!opthdr) {
1480                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1481                         break;
1482                 }
1483
1484                 ip_proto = opthdr[0];
1485                 nhoff += (opthdr[1] + 1) << 3;
1486
1487                 fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
1488                 break;
1489         }
1490         case NEXTHDR_FRAGMENT: {
1491                 struct frag_hdr _fh, *fh;
1492
1493                 if (proto != htons(ETH_P_IPV6))
1494                         break;
1495
1496                 fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
1497                                           data, hlen, &_fh);
1498
1499                 if (!fh) {
1500                         fdret = FLOW_DISSECT_RET_OUT_BAD;
1501                         break;
1502                 }
1503
1504                 key_control->flags |= FLOW_DIS_IS_FRAGMENT;
1505
1506                 nhoff += sizeof(_fh);
1507                 ip_proto = fh->nexthdr;
1508
1509                 if (!(fh->frag_off & htons(IP6_OFFSET))) {
1510                         key_control->flags |= FLOW_DIS_FIRST_FRAG;
1511                         if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
1512                                 fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
1513                                 break;
1514                         }
1515                 }
1516
1517                 fdret = FLOW_DISSECT_RET_OUT_GOOD;
1518                 break;
1519         }
1520         case IPPROTO_IPIP:
1521                 if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1522                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1523                         break;
1524                 }
1525
1526                 proto = htons(ETH_P_IP);
1527
1528                 key_control->flags |= FLOW_DIS_ENCAPSULATION;
1529                 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
1530                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1531                         break;
1532                 }
1533
1534                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1535                 break;
1536
1537         case IPPROTO_IPV6:
1538                 if (flags & FLOW_DISSECTOR_F_STOP_BEFORE_ENCAP) {
1539                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1540                         break;
1541                 }
1542
1543                 proto = htons(ETH_P_IPV6);
1544
1545                 key_control->flags |= FLOW_DIS_ENCAPSULATION;
1546                 if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
1547                         fdret = FLOW_DISSECT_RET_OUT_GOOD;
1548                         break;
1549                 }
1550
1551                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1552                 break;
1553
1554
1555         case IPPROTO_MPLS:
1556                 proto = htons(ETH_P_MPLS_UC);
1557                 fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
1558                 break;
1559
1560         case IPPROTO_TCP:
1561                 __skb_flow_dissect_tcp(skb, flow_dissector, target_container,
1562                                        data, nhoff, hlen);
1563                 break;
1564
1565         case IPPROTO_ICMP:
1566         case IPPROTO_ICMPV6:
1567                 __skb_flow_dissect_icmp(skb, flow_dissector, target_container,
1568                                         data, nhoff, hlen);
1569                 break;
1570         case IPPROTO_L2TP:
1571                 __skb_flow_dissect_l2tpv3(skb, flow_dissector, target_container,
1572                                           data, nhoff, hlen);
1573                 break;
1574
1575         default:
1576                 break;
1577         }
1578
1579         if (!(key_control->flags & FLOW_DIS_IS_FRAGMENT))
1580                 __skb_flow_dissect_ports(skb, flow_dissector, target_container,
1581                                          data, nhoff, ip_proto, hlen);
1582
1583         /* Process result of IP proto processing */
1584         switch (fdret) {
1585         case FLOW_DISSECT_RET_PROTO_AGAIN:
1586                 if (skb_flow_dissect_allowed(&num_hdrs))
1587                         goto proto_again;
1588                 break;
1589         case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1590                 if (skb_flow_dissect_allowed(&num_hdrs))
1591                         goto ip_proto_again;
1592                 break;
1593         case FLOW_DISSECT_RET_OUT_GOOD:
1594         case FLOW_DISSECT_RET_CONTINUE:
1595                 break;
1596         case FLOW_DISSECT_RET_OUT_BAD:
1597         default:
1598                 goto out_bad;
1599         }
1600
1601 out_good:
1602         ret = true;
1603
1604 out:
1605         key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
1606         key_basic->n_proto = proto;
1607         key_basic->ip_proto = ip_proto;
1608
1609         return ret;
1610
1611 out_bad:
1612         ret = false;
1613         goto out;
1614 }
1615 EXPORT_SYMBOL(__skb_flow_dissect);
1616
1617 static siphash_aligned_key_t hashrnd;
1618 static __always_inline void __flow_hash_secret_init(void)
1619 {
1620         net_get_random_once(&hashrnd, sizeof(hashrnd));
1621 }
1622
1623 static const void *flow_keys_hash_start(const struct flow_keys *flow)
1624 {
1625         BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % SIPHASH_ALIGNMENT);
1626         return &flow->FLOW_KEYS_HASH_START_FIELD;
1627 }
1628
1629 static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
1630 {
1631         size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
1632
1633         BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
1634
1635         switch (flow->control.addr_type) {
1636         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1637                 diff -= sizeof(flow->addrs.v4addrs);
1638                 break;
1639         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1640                 diff -= sizeof(flow->addrs.v6addrs);
1641                 break;
1642         case FLOW_DISSECTOR_KEY_TIPC:
1643                 diff -= sizeof(flow->addrs.tipckey);
1644                 break;
1645         }
1646         return sizeof(*flow) - diff;
1647 }
1648
1649 __be32 flow_get_u32_src(const struct flow_keys *flow)
1650 {
1651         switch (flow->control.addr_type) {
1652         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1653                 return flow->addrs.v4addrs.src;
1654         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1655                 return (__force __be32)ipv6_addr_hash(
1656                         &flow->addrs.v6addrs.src);
1657         case FLOW_DISSECTOR_KEY_TIPC:
1658                 return flow->addrs.tipckey.key;
1659         default:
1660                 return 0;
1661         }
1662 }
1663 EXPORT_SYMBOL(flow_get_u32_src);
1664
1665 __be32 flow_get_u32_dst(const struct flow_keys *flow)
1666 {
1667         switch (flow->control.addr_type) {
1668         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1669                 return flow->addrs.v4addrs.dst;
1670         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1671                 return (__force __be32)ipv6_addr_hash(
1672                         &flow->addrs.v6addrs.dst);
1673         default:
1674                 return 0;
1675         }
1676 }
1677 EXPORT_SYMBOL(flow_get_u32_dst);
1678
1679 /* Sort the source and destination IP and the ports,
1680  * to have consistent hash within the two directions
1681  */
1682 static inline void __flow_hash_consistentify(struct flow_keys *keys)
1683 {
1684         int addr_diff, i;
1685
1686         switch (keys->control.addr_type) {
1687         case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
1688                 if ((__force u32)keys->addrs.v4addrs.dst <
1689                     (__force u32)keys->addrs.v4addrs.src)
1690                         swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
1691
1692                 if ((__force u16)keys->ports.dst <
1693                     (__force u16)keys->ports.src) {
1694                         swap(keys->ports.src, keys->ports.dst);
1695                 }
1696                 break;
1697         case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
1698                 addr_diff = memcmp(&keys->addrs.v6addrs.dst,
1699                                    &keys->addrs.v6addrs.src,
1700                                    sizeof(keys->addrs.v6addrs.dst));
1701                 if (addr_diff < 0) {
1702                         for (i = 0; i < 4; i++)
1703                                 swap(keys->addrs.v6addrs.src.s6_addr32[i],
1704                                      keys->addrs.v6addrs.dst.s6_addr32[i]);
1705                 }
1706                 if ((__force u16)keys->ports.dst <
1707                     (__force u16)keys->ports.src) {
1708                         swap(keys->ports.src, keys->ports.dst);
1709                 }
1710                 break;
1711         }
1712 }
1713
1714 static inline u32 __flow_hash_from_keys(struct flow_keys *keys,
1715                                         const siphash_key_t *keyval)
1716 {
1717         u32 hash;
1718
1719         __flow_hash_consistentify(keys);
1720
1721         hash = siphash(flow_keys_hash_start(keys),
1722                        flow_keys_hash_length(keys), keyval);
1723         if (!hash)
1724                 hash = 1;
1725
1726         return hash;
1727 }
1728
1729 u32 flow_hash_from_keys(struct flow_keys *keys)
1730 {
1731         __flow_hash_secret_init();
1732         return __flow_hash_from_keys(keys, &hashrnd);
1733 }
1734 EXPORT_SYMBOL(flow_hash_from_keys);
1735
1736 static inline u32 ___skb_get_hash(const struct sk_buff *skb,
1737                                   struct flow_keys *keys,
1738                                   const siphash_key_t *keyval)
1739 {
1740         skb_flow_dissect_flow_keys(skb, keys,
1741                                    FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1742
1743         return __flow_hash_from_keys(keys, keyval);
1744 }
1745
1746 struct _flow_keys_digest_data {
1747         __be16  n_proto;
1748         u8      ip_proto;
1749         u8      padding;
1750         __be32  ports;
1751         __be32  src;
1752         __be32  dst;
1753 };
1754
1755 void make_flow_keys_digest(struct flow_keys_digest *digest,
1756                            const struct flow_keys *flow)
1757 {
1758         struct _flow_keys_digest_data *data =
1759             (struct _flow_keys_digest_data *)digest;
1760
1761         BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));
1762
1763         memset(digest, 0, sizeof(*digest));
1764
1765         data->n_proto = flow->basic.n_proto;
1766         data->ip_proto = flow->basic.ip_proto;
1767         data->ports = flow->ports.ports;
1768         data->src = flow->addrs.v4addrs.src;
1769         data->dst = flow->addrs.v4addrs.dst;
1770 }
1771 EXPORT_SYMBOL(make_flow_keys_digest);
1772
1773 static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;
1774
1775 u32 __skb_get_hash_symmetric(const struct sk_buff *skb)
1776 {
1777         struct flow_keys keys;
1778
1779         __flow_hash_secret_init();
1780
1781         memset(&keys, 0, sizeof(keys));
1782         __skb_flow_dissect(NULL, skb, &flow_keys_dissector_symmetric,
1783                            &keys, NULL, 0, 0, 0,
1784                            FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
1785
1786         return __flow_hash_from_keys(&keys, &hashrnd);
1787 }
1788 EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric);
1789
1790 /**
1791  * __skb_get_hash: calculate a flow hash
1792  * @skb: sk_buff to calculate flow hash from
1793  *
1794  * This function calculates a flow hash based on src/dst addresses
1795  * and src/dst port numbers.  Sets hash in skb to non-zero hash value
1796  * on success, zero indicates no valid hash.  Also, sets l4_hash in skb
1797  * if hash is a canonical 4-tuple hash over transport ports.
1798  */
1799 void __skb_get_hash(struct sk_buff *skb)
1800 {
1801         struct flow_keys keys;
1802         u32 hash;
1803
1804         __flow_hash_secret_init();
1805
1806         hash = ___skb_get_hash(skb, &keys, &hashrnd);
1807
1808         __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
1809 }
1810 EXPORT_SYMBOL(__skb_get_hash);
1811
1812 __u32 skb_get_hash_perturb(const struct sk_buff *skb,
1813                            const siphash_key_t *perturb)
1814 {
1815         struct flow_keys keys;
1816
1817         return ___skb_get_hash(skb, &keys, perturb);
1818 }
1819 EXPORT_SYMBOL(skb_get_hash_perturb);
1820
1821 u32 __skb_get_poff(const struct sk_buff *skb, const void *data,
1822                    const struct flow_keys_basic *keys, int hlen)
1823 {
1824         u32 poff = keys->control.thoff;
1825
1826         /* skip L4 headers for fragments after the first */
1827         if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
1828             !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
1829                 return poff;
1830
1831         switch (keys->basic.ip_proto) {
1832         case IPPROTO_TCP: {
1833                 /* access doff as u8 to avoid unaligned access */
1834                 const u8 *doff;
1835                 u8 _doff;
1836
1837                 doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
1838                                             data, hlen, &_doff);
1839                 if (!doff)
1840                         return poff;
1841
1842                 poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
1843                 break;
1844         }
1845         case IPPROTO_UDP:
1846         case IPPROTO_UDPLITE:
1847                 poff += sizeof(struct udphdr);
1848                 break;
1849         /* For the rest, we do not really care about header
1850          * extensions at this point for now.
1851          */
1852         case IPPROTO_ICMP:
1853                 poff += sizeof(struct icmphdr);
1854                 break;
1855         case IPPROTO_ICMPV6:
1856                 poff += sizeof(struct icmp6hdr);
1857                 break;
1858         case IPPROTO_IGMP:
1859                 poff += sizeof(struct igmphdr);
1860                 break;
1861         case IPPROTO_DCCP:
1862                 poff += sizeof(struct dccp_hdr);
1863                 break;
1864         case IPPROTO_SCTP:
1865                 poff += sizeof(struct sctphdr);
1866                 break;
1867         }
1868
1869         return poff;
1870 }
1871
1872 /**
1873  * skb_get_poff - get the offset to the payload
1874  * @skb: sk_buff to get the payload offset from
1875  *
1876  * The function will get the offset to the payload as far as it could
1877  * be dissected.  The main user is currently BPF, so that we can dynamically
1878  * truncate packets without needing to push actual payload to the user
1879  * space and can analyze headers only, instead.
1880  */
1881 u32 skb_get_poff(const struct sk_buff *skb)
1882 {
1883         struct flow_keys_basic keys;
1884
1885         if (!skb_flow_dissect_flow_keys_basic(NULL, skb, &keys,
1886                                               NULL, 0, 0, 0, 0))
1887                 return 0;
1888
1889         return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
1890 }
1891
1892 __u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
1893 {
1894         memset(keys, 0, sizeof(*keys));
1895
1896         memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
1897             sizeof(keys->addrs.v6addrs.src));
1898         memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
1899             sizeof(keys->addrs.v6addrs.dst));
1900         keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
1901         keys->ports.src = fl6->fl6_sport;
1902         keys->ports.dst = fl6->fl6_dport;
1903         keys->keyid.keyid = fl6->fl6_gre_key;
1904         keys->tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
1905         keys->basic.ip_proto = fl6->flowi6_proto;
1906
1907         return flow_hash_from_keys(keys);
1908 }
1909 EXPORT_SYMBOL(__get_hash_from_flowi6);
1910
1911 static const struct flow_dissector_key flow_keys_dissector_keys[] = {
1912         {
1913                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1914                 .offset = offsetof(struct flow_keys, control),
1915         },
1916         {
1917                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1918                 .offset = offsetof(struct flow_keys, basic),
1919         },
1920         {
1921                 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1922                 .offset = offsetof(struct flow_keys, addrs.v4addrs),
1923         },
1924         {
1925                 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1926                 .offset = offsetof(struct flow_keys, addrs.v6addrs),
1927         },
1928         {
1929                 .key_id = FLOW_DISSECTOR_KEY_TIPC,
1930                 .offset = offsetof(struct flow_keys, addrs.tipckey),
1931         },
1932         {
1933                 .key_id = FLOW_DISSECTOR_KEY_PORTS,
1934                 .offset = offsetof(struct flow_keys, ports),
1935         },
1936         {
1937                 .key_id = FLOW_DISSECTOR_KEY_VLAN,
1938                 .offset = offsetof(struct flow_keys, vlan),
1939         },
1940         {
1941                 .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
1942                 .offset = offsetof(struct flow_keys, tags),
1943         },
1944         {
1945                 .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
1946                 .offset = offsetof(struct flow_keys, keyid),
1947         },
1948 };
1949
1950 static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
1951         {
1952                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1953                 .offset = offsetof(struct flow_keys, control),
1954         },
1955         {
1956                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1957                 .offset = offsetof(struct flow_keys, basic),
1958         },
1959         {
1960                 .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1961                 .offset = offsetof(struct flow_keys, addrs.v4addrs),
1962         },
1963         {
1964                 .key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
1965                 .offset = offsetof(struct flow_keys, addrs.v6addrs),
1966         },
1967         {
1968                 .key_id = FLOW_DISSECTOR_KEY_PORTS,
1969                 .offset = offsetof(struct flow_keys, ports),
1970         },
1971 };
1972
1973 static const struct flow_dissector_key flow_keys_basic_dissector_keys[] = {
1974         {
1975                 .key_id = FLOW_DISSECTOR_KEY_CONTROL,
1976                 .offset = offsetof(struct flow_keys, control),
1977         },
1978         {
1979                 .key_id = FLOW_DISSECTOR_KEY_BASIC,
1980                 .offset = offsetof(struct flow_keys, basic),
1981         },
1982 };
1983
1984 struct flow_dissector flow_keys_dissector __read_mostly;
1985 EXPORT_SYMBOL(flow_keys_dissector);
1986
1987 struct flow_dissector flow_keys_basic_dissector __read_mostly;
1988 EXPORT_SYMBOL(flow_keys_basic_dissector);
1989
1990 static int __init init_default_flow_dissectors(void)
1991 {
1992         skb_flow_dissector_init(&flow_keys_dissector,
1993                                 flow_keys_dissector_keys,
1994                                 ARRAY_SIZE(flow_keys_dissector_keys));
1995         skb_flow_dissector_init(&flow_keys_dissector_symmetric,
1996                                 flow_keys_dissector_symmetric_keys,
1997                                 ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
1998         skb_flow_dissector_init(&flow_keys_basic_dissector,
1999                                 flow_keys_basic_dissector_keys,
2000                                 ARRAY_SIZE(flow_keys_basic_dissector_keys));
2001         return 0;
2002 }
2003 core_initcall(init_default_flow_dissectors);