net/openvswitch/flow.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2007-2014 Nicira, Inc.
   4  */
   5
   6 #include <linux/uaccess.h>
   7 #include <linux/netdevice.h>
   8 #include <linux/etherdevice.h>
   9 #include <linux/if_ether.h>
  10 #include <linux/if_vlan.h>
  11 #include <net/llc_pdu.h>
  12 #include <linux/kernel.h>
  13 #include <linux/jhash.h>
  14 #include <linux/jiffies.h>
  15 #include <linux/llc.h>
  16 #include <linux/module.h>
  17 #include <linux/in.h>
  18 #include <linux/rcupdate.h>
  19 #include <linux/cpumask.h>
  20 #include <linux/if_arp.h>
  21 #include <linux/ip.h>
  22 #include <linux/ipv6.h>
  23 #include <linux/mpls.h>
  24 #include <linux/sctp.h>
  25 #include <linux/smp.h>
  26 #include <linux/tcp.h>
  27 #include <linux/udp.h>
  28 #include <linux/icmp.h>
  29 #include <linux/icmpv6.h>
  30 #include <linux/rculist.h>
  31 #include <net/ip.h>
  32 #include <net/ip_tunnels.h>
  33 #include <net/ipv6.h>
  34 #include <net/mpls.h>
  35 #include <net/ndisc.h>
  36 #include <net/nsh.h>
  37 #include <net/netfilter/nf_conntrack_zones.h>
  38
  39 #include "conntrack.h"
  40 #include "datapath.h"
  41 #include "flow.h"
  42 #include "flow_netlink.h"
  43 #include "vport.h"
  44
  45 u64 ovs_flow_used_time(unsigned long flow_jiffies)
  46 {
  47         struct timespec64 cur_ts;
  48         u64 cur_ms, idle_ms;
  49
  50         ktime_get_ts64(&cur_ts);
  51         idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
  52         cur_ms = (u64)(u32)cur_ts.tv_sec * MSEC_PER_SEC +
  53                  cur_ts.tv_nsec / NSEC_PER_MSEC;
  54
  55         return cur_ms - idle_ms;
  56 }
  57
  58 #define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
  59
  60 void ovs_flow_stats_update(struct sw_flow *flow, __be16 tcp_flags,
  61                            const struct sk_buff *skb)
  62 {
  63         struct sw_flow_stats *stats;
  64         unsigned int cpu = smp_processor_id();
  65         int len = skb->len + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0);
  66
  67         stats = rcu_dereference(flow->stats[cpu]);
  68
  69         /* Check if already have CPU-specific stats. */
  70         if (likely(stats)) {
  71                 spin_lock(&stats->lock);
  72                 /* Mark if we write on the pre-allocated stats. */
  73                 if (cpu == 0 && unlikely(flow->stats_last_writer != cpu))
  74                         flow->stats_last_writer = cpu;
  75         } else {
  76                 stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
  77                 spin_lock(&stats->lock);
  78
  79                 /* If the current CPU is the only writer on the
  80                  * pre-allocated stats keep using them.
  81                  */
  82                 if (unlikely(flow->stats_last_writer != cpu)) {
  83                         /* A previous locker may have already allocated the
  84                          * stats, so we need to check again.  If CPU-specific
  85                          * stats were already allocated, we update the pre-
  86                          * allocated stats as we have already locked them.
  87                          */
  88                         if (likely(flow->stats_last_writer != -1) &&
  89                             likely(!rcu_access_pointer(flow->stats[cpu]))) {
  90                                 /* Try to allocate CPU-specific stats. */
  91                                 struct sw_flow_stats *new_stats;
  92
  93                                 new_stats =
  94                                         kmem_cache_alloc_node(flow_stats_cache,
  95                                                               GFP_NOWAIT |
  96                                                               __GFP_THISNODE |
  97                                                               __GFP_NOWARN |
  98                                                               __GFP_NOMEMALLOC,
  99                                                               numa_node_id());
 100                                 if (likely(new_stats)) {
 101                                         new_stats->used = jiffies;
 102                                         new_stats->packet_count = 1;
 103                                         new_stats->byte_count = len;
 104                                         new_stats->tcp_flags = tcp_flags;
 105                                         spin_lock_init(&new_stats->lock);
 106
 107                                         rcu_assign_pointer(flow->stats[cpu],
 108                                                            new_stats);
 109                                         cpumask_set_cpu(cpu, &flow->cpu_used_mask);
 110                                         goto unlock;
 111                                 }
 112                         }
 113                         flow->stats_last_writer = cpu;
 114                 }
 115         }
 116
 117         stats->used = jiffies;
 118         stats->packet_count++;
 119         stats->byte_count += len;
 120         stats->tcp_flags |= tcp_flags;
 121 unlock:
 122         spin_unlock(&stats->lock);
 123 }
 124
 125 /* Must be called with rcu_read_lock or ovs_mutex. */
 126 void ovs_flow_stats_get(const struct sw_flow *flow,
 127                         struct ovs_flow_stats *ovs_stats,
 128                         unsigned long *used, __be16 *tcp_flags)
 129 {
 130         int cpu;
 131
 132         *used = 0;
 133         *tcp_flags = 0;
 134         memset(ovs_stats, 0, sizeof(*ovs_stats));
 135
 136         /* We open code this to make sure cpu 0 is always considered */
 137         for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, &flow->cpu_used_mask)) {
 138                 struct sw_flow_stats *stats = rcu_dereference_ovsl(flow->stats[cpu]);
 139
 140                 if (stats) {
 141                         /* Local CPU may write on non-local stats, so we must
 142                          * block bottom-halves here.
 143                          */
 144                         spin_lock_bh(&stats->lock);
 145                         if (!*used || time_after(stats->used, *used))
 146                                 *used = stats->used;
 147                         *tcp_flags |= stats->tcp_flags;
 148                         ovs_stats->n_packets += stats->packet_count;
 149                         ovs_stats->n_bytes += stats->byte_count;
 150                         spin_unlock_bh(&stats->lock);
 151                 }
 152         }
 153 }
 154
 155 /* Called with ovs_mutex. */
 156 void ovs_flow_stats_clear(struct sw_flow *flow)
 157 {
 158         int cpu;
 159
 160         /* We open code this to make sure cpu 0 is always considered */
 161         for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, &flow->cpu_used_mask)) {
 162                 struct sw_flow_stats *stats = ovsl_dereference(flow->stats[cpu]);
 163
 164                 if (stats) {
 165                         spin_lock_bh(&stats->lock);
 166                         stats->used = 0;
 167                         stats->packet_count = 0;
 168                         stats->byte_count = 0;
 169                         stats->tcp_flags = 0;
 170                         spin_unlock_bh(&stats->lock);
 171                 }
 172         }
 173 }
 174
 175 static int check_header(struct sk_buff *skb, int len)
 176 {
 177         if (unlikely(skb->len < len))
 178                 return -EINVAL;
 179         if (unlikely(!pskb_may_pull(skb, len)))
 180                 return -ENOMEM;
 181         return 0;
 182 }
 183
 184 static bool arphdr_ok(struct sk_buff *skb)
 185 {
 186         return pskb_may_pull(skb, skb_network_offset(skb) +
 187                                   sizeof(struct arp_eth_header));
 188 }
 189
 190 static int check_iphdr(struct sk_buff *skb)
 191 {
 192         unsigned int nh_ofs = skb_network_offset(skb);
 193         unsigned int ip_len;
 194         int err;
 195
 196         err = check_header(skb, nh_ofs + sizeof(struct iphdr));
 197         if (unlikely(err))
 198                 return err;
 199
 200         ip_len = ip_hdrlen(skb);
 201         if (unlikely(ip_len < sizeof(struct iphdr) ||
 202                      skb->len < nh_ofs + ip_len))
 203                 return -EINVAL;
 204
 205         skb_set_transport_header(skb, nh_ofs + ip_len);
 206         return 0;
 207 }
 208
 209 static bool tcphdr_ok(struct sk_buff *skb)
 210 {
 211         int th_ofs = skb_transport_offset(skb);
 212         int tcp_len;
 213
 214         if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
 215                 return false;
 216
 217         tcp_len = tcp_hdrlen(skb);
 218         if (unlikely(tcp_len < sizeof(struct tcphdr) ||
 219                      skb->len < th_ofs + tcp_len))
 220                 return false;
 221
 222         return true;
 223 }
 224
 225 static bool udphdr_ok(struct sk_buff *skb)
 226 {
 227         return pskb_may_pull(skb, skb_transport_offset(skb) +
 228                                   sizeof(struct udphdr));
 229 }
 230
 231 static bool sctphdr_ok(struct sk_buff *skb)
 232 {
 233         return pskb_may_pull(skb, skb_transport_offset(skb) +
 234                                   sizeof(struct sctphdr));
 235 }
 236
 237 static bool icmphdr_ok(struct sk_buff *skb)
 238 {
 239         return pskb_may_pull(skb, skb_transport_offset(skb) +
 240                                   sizeof(struct icmphdr));
 241 }
 242
 243 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
 244 {
 245         unsigned short frag_off;
 246         unsigned int payload_ofs = 0;
 247         unsigned int nh_ofs = skb_network_offset(skb);
 248         unsigned int nh_len;
 249         struct ipv6hdr *nh;
 250         int err, nexthdr, flags = 0;
 251
 252         err = check_header(skb, nh_ofs + sizeof(*nh));
 253         if (unlikely(err))
 254                 return err;
 255
 256         nh = ipv6_hdr(skb);
 257
 258         key->ip.proto = NEXTHDR_NONE;
 259         key->ip.tos = ipv6_get_dsfield(nh);
 260         key->ip.ttl = nh->hop_limit;
 261         key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 262         key->ipv6.addr.src = nh->saddr;
 263         key->ipv6.addr.dst = nh->daddr;
 264
 265         nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
 266         if (flags & IP6_FH_F_FRAG) {
 267                 if (frag_off) {
 268                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 269                         key->ip.proto = nexthdr;
 270                         return 0;
 271                 }
 272                 key->ip.frag = OVS_FRAG_TYPE_FIRST;
 273         } else {
 274                 key->ip.frag = OVS_FRAG_TYPE_NONE;
 275         }
 276
 277         /* Delayed handling of error in ipv6_find_hdr() as it
 278          * always sets flags and frag_off to a valid value which may be
 279          * used to set key->ip.frag above.
 280          */
 281         if (unlikely(nexthdr < 0))
 282                 return -EPROTO;
 283
 284         nh_len = payload_ofs - nh_ofs;
 285         skb_set_transport_header(skb, nh_ofs + nh_len);
 286         key->ip.proto = nexthdr;
 287         return nh_len;
 288 }
 289
 290 static bool icmp6hdr_ok(struct sk_buff *skb)
 291 {
 292         return pskb_may_pull(skb, skb_transport_offset(skb) +
 293                                   sizeof(struct icmp6hdr));
 294 }
 295
 296 /**
 297  * parse_vlan_tag - Parse vlan tag from vlan header.
 298  * @skb: skb containing frame to parse
 299  * @key_vh: pointer to parsed vlan tag
 300  * @untag_vlan: should the vlan header be removed from the frame
 301  *
 302  * Return: ERROR on memory error.
 303  * %0 if it encounters a non-vlan or incomplete packet.
 304  * %1 after successfully parsing vlan tag.
 305  */
 306 static int parse_vlan_tag(struct sk_buff *skb, struct vlan_head *key_vh,
 307                           bool untag_vlan)
 308 {
 309         struct vlan_head *vh = (struct vlan_head *)skb->data;
 310
 311         if (likely(!eth_type_vlan(vh->tpid)))
 312                 return 0;
 313
 314         if (unlikely(skb->len < sizeof(struct vlan_head) + sizeof(__be16)))
 315                 return 0;
 316
 317         if (unlikely(!pskb_may_pull(skb, sizeof(struct vlan_head) +
 318                                  sizeof(__be16))))
 319                 return -ENOMEM;
 320
 321         vh = (struct vlan_head *)skb->data;
 322         key_vh->tci = vh->tci | htons(VLAN_CFI_MASK);
 323         key_vh->tpid = vh->tpid;
 324
 325         if (unlikely(untag_vlan)) {
 326                 int offset = skb->data - skb_mac_header(skb);
 327                 u16 tci;
 328                 int err;
 329
 330                 __skb_push(skb, offset);
 331                 err = __skb_vlan_pop(skb, &tci);
 332                 __skb_pull(skb, offset);
 333                 if (err)
 334                         return err;
 335                 __vlan_hwaccel_put_tag(skb, key_vh->tpid, tci);
 336         } else {
 337                 __skb_pull(skb, sizeof(struct vlan_head));
 338         }
 339         return 1;
 340 }
 341
 342 static void clear_vlan(struct sw_flow_key *key)
 343 {
 344         key->eth.vlan.tci = 0;
 345         key->eth.vlan.tpid = 0;
 346         key->eth.cvlan.tci = 0;
 347         key->eth.cvlan.tpid = 0;
 348 }
 349
 350 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 351 {
 352         int res;
 353
 354         if (skb_vlan_tag_present(skb)) {
 355                 key->eth.vlan.tci = htons(skb->vlan_tci) | htons(VLAN_CFI_MASK);
 356                 key->eth.vlan.tpid = skb->vlan_proto;
 357         } else {
 358                 /* Parse outer vlan tag in the non-accelerated case. */
 359                 res = parse_vlan_tag(skb, &key->eth.vlan, true);
 360                 if (res <= 0)
 361                         return res;
 362         }
 363
 364         /* Parse inner vlan tag. */
 365         res = parse_vlan_tag(skb, &key->eth.cvlan, false);
 366         if (res <= 0)
 367                 return res;
 368
 369         return 0;
 370 }
 371
 372 static __be16 parse_ethertype(struct sk_buff *skb)
 373 {
 374         struct llc_snap_hdr {
 375                 u8  dsap;  /* Always 0xAA */
 376                 u8  ssap;  /* Always 0xAA */
 377                 u8  ctrl;
 378                 u8  oui[3];
 379                 __be16 ethertype;
 380         };
 381         struct llc_snap_hdr *llc;
 382         __be16 proto;
 383
 384         proto = *(__be16 *) skb->data;
 385         __skb_pull(skb, sizeof(__be16));
 386
 387         if (eth_proto_is_802_3(proto))
 388                 return proto;
 389
 390         if (skb->len < sizeof(struct llc_snap_hdr))
 391                 return htons(ETH_P_802_2);
 392
 393         if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
 394                 return htons(0);
 395
 396         llc = (struct llc_snap_hdr *) skb->data;
 397         if (llc->dsap != LLC_SAP_SNAP ||
 398             llc->ssap != LLC_SAP_SNAP ||
 399             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
 400                 return htons(ETH_P_802_2);
 401
 402         __skb_pull(skb, sizeof(struct llc_snap_hdr));
 403
 404         if (eth_proto_is_802_3(llc->ethertype))
 405                 return llc->ethertype;
 406
 407         return htons(ETH_P_802_2);
 408 }
 409
 410 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
 411                         int nh_len)
 412 {
 413         struct icmp6hdr *icmp = icmp6_hdr(skb);
 414
 415         /* The ICMPv6 type and code fields use the 16-bit transport port
 416          * fields, so we need to store them in 16-bit network byte order.
 417          */
 418         key->tp.src = htons(icmp->icmp6_type);
 419         key->tp.dst = htons(icmp->icmp6_code);
 420         memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd));
 421
 422         if (icmp->icmp6_code == 0 &&
 423             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
 424              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 425                 int icmp_len = skb->len - skb_transport_offset(skb);
 426                 struct nd_msg *nd;
 427                 int offset;
 428
 429                 /* In order to process neighbor discovery options, we need the
 430                  * entire packet.
 431                  */
 432                 if (unlikely(icmp_len < sizeof(*nd)))
 433                         return 0;
 434
 435                 if (unlikely(skb_linearize(skb)))
 436                         return -ENOMEM;
 437
 438                 nd = (struct nd_msg *)skb_transport_header(skb);
 439                 key->ipv6.nd.target = nd->target;
 440
 441                 icmp_len -= sizeof(*nd);
 442                 offset = 0;
 443                 while (icmp_len >= 8) {
 444                         struct nd_opt_hdr *nd_opt =
 445                                  (struct nd_opt_hdr *)(nd->opt + offset);
 446                         int opt_len = nd_opt->nd_opt_len * 8;
 447
 448                         if (unlikely(!opt_len || opt_len > icmp_len))
 449                                 return 0;
 450
 451                         /* Store the link layer address if the appropriate
 452                          * option is provided.  It is considered an error if
 453                          * the same link layer option is specified twice.
 454                          */
 455                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
 456                             && opt_len == 8) {
 457                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
 458                                         goto invalid;
 459                                 ether_addr_copy(key->ipv6.nd.sll,
 460                                                 &nd->opt[offset+sizeof(*nd_opt)]);
 461                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
 462                                    && opt_len == 8) {
 463                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
 464                                         goto invalid;
 465                                 ether_addr_copy(key->ipv6.nd.tll,
 466                                                 &nd->opt[offset+sizeof(*nd_opt)]);
 467                         }
 468
 469                         icmp_len -= opt_len;
 470                         offset += opt_len;
 471                 }
 472         }
 473
 474         return 0;
 475
 476 invalid:
 477         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
 478         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
 479         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
 480
 481         return 0;
 482 }
 483
 484 static int parse_nsh(struct sk_buff *skb, struct sw_flow_key *key)
 485 {
 486         struct nshhdr *nh;
 487         unsigned int nh_ofs = skb_network_offset(skb);
 488         u8 version, length;
 489         int err;
 490
 491         err = check_header(skb, nh_ofs + NSH_BASE_HDR_LEN);
 492         if (unlikely(err))
 493                 return err;
 494
 495         nh = nsh_hdr(skb);
 496         version = nsh_get_ver(nh);
 497         length = nsh_hdr_len(nh);
 498
 499         if (version != 0)
 500                 return -EINVAL;
 501
 502         err = check_header(skb, nh_ofs + length);
 503         if (unlikely(err))
 504                 return err;
 505
 506         nh = nsh_hdr(skb);
 507         key->nsh.base.flags = nsh_get_flags(nh);
 508         key->nsh.base.ttl = nsh_get_ttl(nh);
 509         key->nsh.base.mdtype = nh->mdtype;
 510         key->nsh.base.np = nh->np;
 511         key->nsh.base.path_hdr = nh->path_hdr;
 512         switch (key->nsh.base.mdtype) {
 513         case NSH_M_TYPE1:
 514                 if (length != NSH_M_TYPE1_LEN)
 515                         return -EINVAL;
 516                 memcpy(key->nsh.context, nh->md1.context,
 517                        sizeof(nh->md1));
 518                 break;
 519         case NSH_M_TYPE2:
 520                 memset(key->nsh.context, 0,
 521                        sizeof(nh->md1));
 522                 break;
 523         default:
 524                 return -EINVAL;
 525         }
 526
 527         return 0;
 528 }
 529
 530 /**
 531  * key_extract_l3l4 - extracts L3/L4 header information.
 532  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 533  *       L3 header
 534  * @key: output flow key
 535  *
 536  * Return: %0 if successful, otherwise a negative errno value.
 537  */
 538 static int key_extract_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
 539 {
 540         int error;
 541
 542         /* Network layer. */
 543         if (key->eth.type == htons(ETH_P_IP)) {
 544                 struct iphdr *nh;
 545                 __be16 offset;
 546
 547                 error = check_iphdr(skb);
 548                 if (unlikely(error)) {
 549                         memset(&key->ip, 0, sizeof(key->ip));
 550                         memset(&key->ipv4, 0, sizeof(key->ipv4));
 551                         if (error == -EINVAL) {
 552                                 skb->transport_header = skb->network_header;
 553                                 error = 0;
 554                         }
 555                         return error;
 556                 }
 557
 558                 nh = ip_hdr(skb);
 559                 key->ipv4.addr.src = nh->saddr;
 560                 key->ipv4.addr.dst = nh->daddr;
 561
 562                 key->ip.proto = nh->protocol;
 563                 key->ip.tos = nh->tos;
 564                 key->ip.ttl = nh->ttl;
 565
 566                 offset = nh->frag_off & htons(IP_OFFSET);
 567                 if (offset) {
 568                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 569                         memset(&key->tp, 0, sizeof(key->tp));
 570                         return 0;
 571                 }
 572                 if (nh->frag_off & htons(IP_MF) ||
 573                         skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 574                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 575                 else
 576                         key->ip.frag = OVS_FRAG_TYPE_NONE;
 577
 578                 /* Transport layer. */
 579                 if (key->ip.proto == IPPROTO_TCP) {
 580                         if (tcphdr_ok(skb)) {
 581                                 struct tcphdr *tcp = tcp_hdr(skb);
 582                                 key->tp.src = tcp->source;
 583                                 key->tp.dst = tcp->dest;
 584                                 key->tp.flags = TCP_FLAGS_BE16(tcp);
 585                         } else {
 586                                 memset(&key->tp, 0, sizeof(key->tp));
 587                         }
 588
 589                 } else if (key->ip.proto == IPPROTO_UDP) {
 590                         if (udphdr_ok(skb)) {
 591                                 struct udphdr *udp = udp_hdr(skb);
 592                                 key->tp.src = udp->source;
 593                                 key->tp.dst = udp->dest;
 594                         } else {
 595                                 memset(&key->tp, 0, sizeof(key->tp));
 596                         }
 597                 } else if (key->ip.proto == IPPROTO_SCTP) {
 598                         if (sctphdr_ok(skb)) {
 599                                 struct sctphdr *sctp = sctp_hdr(skb);
 600                                 key->tp.src = sctp->source;
 601                                 key->tp.dst = sctp->dest;
 602                         } else {
 603                                 memset(&key->tp, 0, sizeof(key->tp));
 604                         }
 605                 } else if (key->ip.proto == IPPROTO_ICMP) {
 606                         if (icmphdr_ok(skb)) {
 607                                 struct icmphdr *icmp = icmp_hdr(skb);
 608                                 /* The ICMP type and code fields use the 16-bit
 609                                  * transport port fields, so we need to store
 610                                  * them in 16-bit network byte order. */
 611                                 key->tp.src = htons(icmp->type);
 612                                 key->tp.dst = htons(icmp->code);
 613                         } else {
 614                                 memset(&key->tp, 0, sizeof(key->tp));
 615                         }
 616                 }
 617
 618         } else if (key->eth.type == htons(ETH_P_ARP) ||
 619                    key->eth.type == htons(ETH_P_RARP)) {
 620                 struct arp_eth_header *arp;
 621                 bool arp_available = arphdr_ok(skb);
 622
 623                 arp = (struct arp_eth_header *)skb_network_header(skb);
 624
 625                 if (arp_available &&
 626                     arp->ar_hrd == htons(ARPHRD_ETHER) &&
 627                     arp->ar_pro == htons(ETH_P_IP) &&
 628                     arp->ar_hln == ETH_ALEN &&
 629                     arp->ar_pln == 4) {
 630
 631                         /* We only match on the lower 8 bits of the opcode. */
 632                         if (ntohs(arp->ar_op) <= 0xff)
 633                                 key->ip.proto = ntohs(arp->ar_op);
 634                         else
 635                                 key->ip.proto = 0;
 636
 637                         memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
 638                         memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
 639                         ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
 640                         ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
 641                 } else {
 642                         memset(&key->ip, 0, sizeof(key->ip));
 643                         memset(&key->ipv4, 0, sizeof(key->ipv4));
 644                 }
 645         } else if (eth_p_mpls(key->eth.type)) {
 646                 u8 label_count = 1;
 647
 648                 memset(&key->mpls, 0, sizeof(key->mpls));
 649                 skb_set_inner_network_header(skb, skb->mac_len);
 650                 while (1) {
 651                         __be32 lse;
 652
 653                         error = check_header(skb, skb->mac_len +
 654                                              label_count * MPLS_HLEN);
 655                         if (unlikely(error))
 656                                 return 0;
 657
 658                         memcpy(&lse, skb_inner_network_header(skb), MPLS_HLEN);
 659
 660                         if (label_count <= MPLS_LABEL_DEPTH)
 661                                 memcpy(&key->mpls.lse[label_count - 1], &lse,
 662                                        MPLS_HLEN);
 663
 664                         skb_set_inner_network_header(skb, skb->mac_len +
 665                                                      label_count * MPLS_HLEN);
 666                         if (lse & htonl(MPLS_LS_S_MASK))
 667                                 break;
 668
 669                         label_count++;
 670                 }
 671                 if (label_count > MPLS_LABEL_DEPTH)
 672                         label_count = MPLS_LABEL_DEPTH;
 673
 674                 key->mpls.num_labels_mask = GENMASK(label_count - 1, 0);
 675         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 676                 int nh_len;             /* IPv6 Header + Extensions */
 677
 678                 nh_len = parse_ipv6hdr(skb, key);
 679                 if (unlikely(nh_len < 0)) {
 680                         switch (nh_len) {
 681                         case -EINVAL:
 682                                 memset(&key->ip, 0, sizeof(key->ip));
 683                                 memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
 684                                 fallthrough;
 685                         case -EPROTO:
 686                                 skb->transport_header = skb->network_header;
 687                                 error = 0;
 688                                 break;
 689                         default:
 690                                 error = nh_len;
 691                         }
 692                         return error;
 693                 }
 694
 695                 if (key->ip.frag == OVS_FRAG_TYPE_LATER) {
 696                         memset(&key->tp, 0, sizeof(key->tp));
 697                         return 0;
 698                 }
 699                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 700                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 701
 702                 /* Transport layer. */
 703                 if (key->ip.proto == NEXTHDR_TCP) {
 704                         if (tcphdr_ok(skb)) {
 705                                 struct tcphdr *tcp = tcp_hdr(skb);
 706                                 key->tp.src = tcp->source;
 707                                 key->tp.dst = tcp->dest;
 708                                 key->tp.flags = TCP_FLAGS_BE16(tcp);
 709                         } else {
 710                                 memset(&key->tp, 0, sizeof(key->tp));
 711                         }
 712                 } else if (key->ip.proto == NEXTHDR_UDP) {
 713                         if (udphdr_ok(skb)) {
 714                                 struct udphdr *udp = udp_hdr(skb);
 715                                 key->tp.src = udp->source;
 716                                 key->tp.dst = udp->dest;
 717                         } else {
 718                                 memset(&key->tp, 0, sizeof(key->tp));
 719                         }
 720                 } else if (key->ip.proto == NEXTHDR_SCTP) {
 721                         if (sctphdr_ok(skb)) {
 722                                 struct sctphdr *sctp = sctp_hdr(skb);
 723                                 key->tp.src = sctp->source;
 724                                 key->tp.dst = sctp->dest;
 725                         } else {
 726                                 memset(&key->tp, 0, sizeof(key->tp));
 727                         }
 728                 } else if (key->ip.proto == NEXTHDR_ICMP) {
 729                         if (icmp6hdr_ok(skb)) {
 730                                 error = parse_icmpv6(skb, key, nh_len);
 731                                 if (error)
 732                                         return error;
 733                         } else {
 734                                 memset(&key->tp, 0, sizeof(key->tp));
 735                         }
 736                 }
 737         } else if (key->eth.type == htons(ETH_P_NSH)) {
 738                 error = parse_nsh(skb, key);
 739                 if (error)
 740                         return error;
 741         }
 742         return 0;
 743 }
 744
 745 /**
 746  * key_extract - extracts a flow key from an Ethernet frame.
 747  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 748  * Ethernet header
 749  * @key: output flow key
 750  *
 751  * The caller must ensure that skb->len >= ETH_HLEN.
 752  *
 753  * Initializes @skb header fields as follows:
 754  *
 755  *    - skb->mac_header: the L2 header.
 756  *
 757  *    - skb->network_header: just past the L2 header, or just past the
 758  *      VLAN header, to the first byte of the L2 payload.
 759  *
 760  *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
 761  *      on output, then just past the IP header, if one is present and
 762  *      of a correct length, otherwise the same as skb->network_header.
 763  *      For other key->eth.type values it is left untouched.
 764  *
 765  *    - skb->protocol: the type of the data starting at skb->network_header.
 766  *      Equals to key->eth.type.
 767  *
 768  * Return: %0 if successful, otherwise a negative errno value.
 769  */
 770 static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
 771 {
 772         struct ethhdr *eth;
 773
 774         /* Flags are always used as part of stats */
 775         key->tp.flags = 0;
 776
 777         skb_reset_mac_header(skb);
 778
 779         /* Link layer. */
 780         clear_vlan(key);
 781         if (ovs_key_mac_proto(key) == MAC_PROTO_NONE) {
 782                 if (unlikely(eth_type_vlan(skb->protocol)))
 783                         return -EINVAL;
 784
 785                 skb_reset_network_header(skb);
 786                 key->eth.type = skb->protocol;
 787         } else {
 788                 eth = eth_hdr(skb);
 789                 ether_addr_copy(key->eth.src, eth->h_source);
 790                 ether_addr_copy(key->eth.dst, eth->h_dest);
 791
 792                 __skb_pull(skb, 2 * ETH_ALEN);
 793                 /* We are going to push all headers that we pull, so no need to
 794                  * update skb->csum here.
 795                  */
 796
 797                 if (unlikely(parse_vlan(skb, key)))
 798                         return -ENOMEM;
 799
 800                 key->eth.type = parse_ethertype(skb);
 801                 if (unlikely(key->eth.type == htons(0)))
 802                         return -ENOMEM;
 803
 804                 /* Multiple tagged packets need to retain TPID to satisfy
 805                  * skb_vlan_pop(), which will later shift the ethertype into
 806                  * skb->protocol.
 807                  */
 808                 if (key->eth.cvlan.tci & htons(VLAN_CFI_MASK))
 809                         skb->protocol = key->eth.cvlan.tpid;
 810                 else
 811                         skb->protocol = key->eth.type;
 812
 813                 skb_reset_network_header(skb);
 814                 __skb_push(skb, skb->data - skb_mac_header(skb));
 815         }
 816
 817         skb_reset_mac_len(skb);
 818
 819         /* Fill out L3/L4 key info, if any */
 820         return key_extract_l3l4(skb, key);
 821 }
 822
 823 /* In the case of conntrack fragment handling it expects L3 headers,
 824  * add a helper.
 825  */
 826 int ovs_flow_key_update_l3l4(struct sk_buff *skb, struct sw_flow_key *key)
 827 {
 828         return key_extract_l3l4(skb, key);
 829 }
 830
 831 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
 832 {
 833         int res;
 834
 835         res = key_extract(skb, key);
 836         if (!res)
 837                 key->mac_proto &= ~SW_FLOW_KEY_INVALID;
 838
 839         return res;
 840 }
 841
 842 static int key_extract_mac_proto(struct sk_buff *skb)
 843 {
 844         switch (skb->dev->type) {
 845         case ARPHRD_ETHER:
 846                 return MAC_PROTO_ETHERNET;
 847         case ARPHRD_NONE:
 848                 if (skb->protocol == htons(ETH_P_TEB))
 849                         return MAC_PROTO_ETHERNET;
 850                 return MAC_PROTO_NONE;
 851         }
 852         WARN_ON_ONCE(1);
 853         return -EINVAL;
 854 }
 855
 856 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
 857                          struct sk_buff *skb, struct sw_flow_key *key)
 858 {
 859 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
 860         struct tc_skb_ext *tc_ext;
 861 #endif
 862         bool post_ct = false, post_ct_snat = false, post_ct_dnat = false;
 863         int res, err;
 864         u16 zone = 0;
 865
 866         /* Extract metadata from packet. */
 867         if (tun_info) {
 868                 key->tun_proto = ip_tunnel_info_af(tun_info);
 869                 memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key));
 870
 871                 if (tun_info->options_len) {
 872                         BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
 873                                                    8)) - 1
 874                                         > sizeof(key->tun_opts));
 875
 876                         ip_tunnel_info_opts_get(TUN_METADATA_OPTS(key, tun_info->options_len),
 877                                                 tun_info);
 878                         key->tun_opts_len = tun_info->options_len;
 879                 } else {
 880                         key->tun_opts_len = 0;
 881                 }
 882         } else  {
 883                 key->tun_proto = 0;
 884                 key->tun_opts_len = 0;
 885                 memset(&key->tun_key, 0, sizeof(key->tun_key));
 886         }
 887
 888         key->phy.priority = skb->priority;
 889         key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
 890         key->phy.skb_mark = skb->mark;
 891         key->ovs_flow_hash = 0;
 892         res = key_extract_mac_proto(skb);
 893         if (res < 0)
 894                 return res;
 895         key->mac_proto = res;
 896
 897 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
 898         if (static_branch_unlikely(&tc_recirc_sharing_support)) {
 899                 tc_ext = skb_ext_find(skb, TC_SKB_EXT);
 900                 key->recirc_id = tc_ext ? tc_ext->chain : 0;
 901                 OVS_CB(skb)->mru = tc_ext ? tc_ext->mru : 0;
 902                 post_ct = tc_ext ? tc_ext->post_ct : false;
 903                 post_ct_snat = post_ct ? tc_ext->post_ct_snat : false;
 904                 post_ct_dnat = post_ct ? tc_ext->post_ct_dnat : false;
 905                 zone = post_ct ? tc_ext->zone : 0;
 906         } else {
 907                 key->recirc_id = 0;
 908         }
 909 #else
 910         key->recirc_id = 0;
 911 #endif
 912
 913         err = key_extract(skb, key);
 914         if (!err) {
 915                 ovs_ct_fill_key(skb, key, post_ct);   /* Must be after key_extract(). */
 916                 if (post_ct) {
 917                         if (!skb_get_nfct(skb)) {
 918                                 key->ct_zone = zone;
 919                         } else {
 920                                 if (!post_ct_dnat)
 921                                         key->ct_state &= ~OVS_CS_F_DST_NAT;
 922                                 if (!post_ct_snat)
 923                                         key->ct_state &= ~OVS_CS_F_SRC_NAT;
 924                         }
 925                 }
 926         }
 927         return err;
 928 }
 929
 930 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
 931                                    struct sk_buff *skb,
 932                                    struct sw_flow_key *key, bool log)
 933 {
 934         const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
 935         u64 attrs = 0;
 936         int err;
 937
 938         err = parse_flow_nlattrs(attr, a, &attrs, log);
 939         if (err)
 940                 return -EINVAL;
 941
 942         /* Extract metadata from netlink attributes. */
 943         err = ovs_nla_get_flow_metadata(net, a, attrs, key, log);
 944         if (err)
 945                 return err;
 946
 947         /* key_extract assumes that skb->protocol is set-up for
 948          * layer 3 packets which is the case for other callers,
 949          * in particular packets received from the network stack.
 950          * Here the correct value can be set from the metadata
 951          * extracted above.
 952          * For L2 packet key eth type would be zero. skb protocol
 953          * would be set to correct value later during key-extact.
 954          */
 955
 956         skb->protocol = key->eth.type;
 957         err = key_extract(skb, key);
 958         if (err)
 959                 return err;
 960
 961         /* Check that we have conntrack original direction tuple metadata only
 962          * for packets for which it makes sense.  Otherwise the key may be
 963          * corrupted due to overlapping key fields.
 964          */
 965         if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4) &&
 966             key->eth.type != htons(ETH_P_IP))
 967                 return -EINVAL;
 968         if (attrs & (1 << OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6) &&
 969             (key->eth.type != htons(ETH_P_IPV6) ||
 970              sw_flow_key_is_nd(key)))
 971                 return -EINVAL;
 972
 973         return 0;
 974 }