net/openvswitch/flow.c

   1 /*
   2  * Copyright (c) 2007-2014 Nicira, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of version 2 of the GNU General Public
   6  * License as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16  * 02110-1301, USA
  17  */
  18
  19 #include <linux/uaccess.h>
  20 #include <linux/netdevice.h>
  21 #include <linux/etherdevice.h>
  22 #include <linux/if_ether.h>
  23 #include <linux/if_vlan.h>
  24 #include <net/llc_pdu.h>
  25 #include <linux/kernel.h>
  26 #include <linux/jhash.h>
  27 #include <linux/jiffies.h>
  28 #include <linux/llc.h>
  29 #include <linux/module.h>
  30 #include <linux/in.h>
  31 #include <linux/rcupdate.h>
  32 #include <linux/cpumask.h>
  33 #include <linux/if_arp.h>
  34 #include <linux/ip.h>
  35 #include <linux/ipv6.h>
  36 #include <linux/mpls.h>
  37 #include <linux/sctp.h>
  38 #include <linux/smp.h>
  39 #include <linux/tcp.h>
  40 #include <linux/udp.h>
  41 #include <linux/icmp.h>
  42 #include <linux/icmpv6.h>
  43 #include <linux/rculist.h>
  44 #include <net/ip.h>
  45 #include <net/ip_tunnels.h>
  46 #include <net/ipv6.h>
  47 #include <net/mpls.h>
  48 #include <net/ndisc.h>
  49
  50 #include "conntrack.h"
  51 #include "datapath.h"
  52 #include "flow.h"
  53 #include "flow_netlink.h"
  54 #include "vport.h"
  55
  56 u64 ovs_flow_used_time(unsigned long flow_jiffies)
  57 {
  58         struct timespec cur_ts;
  59         u64 cur_ms, idle_ms;
  60
  61         ktime_get_ts(&cur_ts);
  62         idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
  63         cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
  64                  cur_ts.tv_nsec / NSEC_PER_MSEC;
  65
  66         return cur_ms - idle_ms;
  67 }
  68
  69 #define TCP_FLAGS_BE16(tp) (*(__be16 *)&tcp_flag_word(tp) & htons(0x0FFF))
  70
  71 void ovs_flow_stats_update(struct sw_flow *flow, __be16 tcp_flags,
  72                            const struct sk_buff *skb)
  73 {
  74         struct flow_stats *stats;
  75         int node = numa_node_id();
  76         int cpu = smp_processor_id();
  77         int len = skb->len + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0);
  78
  79         stats = rcu_dereference(flow->stats[cpu]);
  80
  81         /* Check if already have CPU-specific stats. */
  82         if (likely(stats)) {
  83                 spin_lock(&stats->lock);
  84                 /* Mark if we write on the pre-allocated stats. */
  85                 if (cpu == 0 && unlikely(flow->stats_last_writer != cpu))
  86                         flow->stats_last_writer = cpu;
  87         } else {
  88                 stats = rcu_dereference(flow->stats[0]); /* Pre-allocated. */
  89                 spin_lock(&stats->lock);
  90
  91                 /* If the current CPU is the only writer on the
  92                  * pre-allocated stats keep using them.
  93                  */
  94                 if (unlikely(flow->stats_last_writer != cpu)) {
  95                         /* A previous locker may have already allocated the
  96                          * stats, so we need to check again.  If CPU-specific
  97                          * stats were already allocated, we update the pre-
  98                          * allocated stats as we have already locked them.
  99                          */
 100                         if (likely(flow->stats_last_writer != -1) &&
 101                             likely(!rcu_access_pointer(flow->stats[cpu]))) {
 102                                 /* Try to allocate CPU-specific stats. */
 103                                 struct flow_stats *new_stats;
 104
 105                                 new_stats =
 106                                         kmem_cache_alloc_node(flow_stats_cache,
 107                                                               GFP_NOWAIT |
 108                                                               __GFP_THISNODE |
 109                                                               __GFP_NOWARN |
 110                                                               __GFP_NOMEMALLOC,
 111                                                               node);
 112                                 if (likely(new_stats)) {
 113                                         new_stats->used = jiffies;
 114                                         new_stats->packet_count = 1;
 115                                         new_stats->byte_count = len;
 116                                         new_stats->tcp_flags = tcp_flags;
 117                                         spin_lock_init(&new_stats->lock);
 118
 119                                         rcu_assign_pointer(flow->stats[cpu],
 120                                                            new_stats);
 121                                         goto unlock;
 122                                 }
 123                         }
 124                         flow->stats_last_writer = cpu;
 125                 }
 126         }
 127
 128         stats->used = jiffies;
 129         stats->packet_count++;
 130         stats->byte_count += len;
 131         stats->tcp_flags |= tcp_flags;
 132 unlock:
 133         spin_unlock(&stats->lock);
 134 }
 135
 136 /* Must be called with rcu_read_lock or ovs_mutex. */
 137 void ovs_flow_stats_get(const struct sw_flow *flow,
 138                         struct ovs_flow_stats *ovs_stats,
 139                         unsigned long *used, __be16 *tcp_flags)
 140 {
 141         int cpu;
 142
 143         *used = 0;
 144         *tcp_flags = 0;
 145         memset(ovs_stats, 0, sizeof(*ovs_stats));
 146
 147         /* We open code this to make sure cpu 0 is always considered */
 148         for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, cpu_possible_mask)) {
 149                 struct flow_stats *stats = rcu_dereference_ovsl(flow->stats[cpu]);
 150
 151                 if (stats) {
 152                         /* Local CPU may write on non-local stats, so we must
 153                          * block bottom-halves here.
 154                          */
 155                         spin_lock_bh(&stats->lock);
 156                         if (!*used || time_after(stats->used, *used))
 157                                 *used = stats->used;
 158                         *tcp_flags |= stats->tcp_flags;
 159                         ovs_stats->n_packets += stats->packet_count;
 160                         ovs_stats->n_bytes += stats->byte_count;
 161                         spin_unlock_bh(&stats->lock);
 162                 }
 163         }
 164 }
 165
 166 /* Called with ovs_mutex. */
 167 void ovs_flow_stats_clear(struct sw_flow *flow)
 168 {
 169         int cpu;
 170
 171         /* We open code this to make sure cpu 0 is always considered */
 172         for (cpu = 0; cpu < nr_cpu_ids; cpu = cpumask_next(cpu, cpu_possible_mask)) {
 173                 struct flow_stats *stats = ovsl_dereference(flow->stats[cpu]);
 174
 175                 if (stats) {
 176                         spin_lock_bh(&stats->lock);
 177                         stats->used = 0;
 178                         stats->packet_count = 0;
 179                         stats->byte_count = 0;
 180                         stats->tcp_flags = 0;
 181                         spin_unlock_bh(&stats->lock);
 182                 }
 183         }
 184 }
 185
 186 static int check_header(struct sk_buff *skb, int len)
 187 {
 188         if (unlikely(skb->len < len))
 189                 return -EINVAL;
 190         if (unlikely(!pskb_may_pull(skb, len)))
 191                 return -ENOMEM;
 192         return 0;
 193 }
 194
 195 static bool arphdr_ok(struct sk_buff *skb)
 196 {
 197         return pskb_may_pull(skb, skb_network_offset(skb) +
 198                                   sizeof(struct arp_eth_header));
 199 }
 200
 201 static int check_iphdr(struct sk_buff *skb)
 202 {
 203         unsigned int nh_ofs = skb_network_offset(skb);
 204         unsigned int ip_len;
 205         int err;
 206
 207         err = check_header(skb, nh_ofs + sizeof(struct iphdr));
 208         if (unlikely(err))
 209                 return err;
 210
 211         ip_len = ip_hdrlen(skb);
 212         if (unlikely(ip_len < sizeof(struct iphdr) ||
 213                      skb->len < nh_ofs + ip_len))
 214                 return -EINVAL;
 215
 216         skb_set_transport_header(skb, nh_ofs + ip_len);
 217         return 0;
 218 }
 219
 220 static bool tcphdr_ok(struct sk_buff *skb)
 221 {
 222         int th_ofs = skb_transport_offset(skb);
 223         int tcp_len;
 224
 225         if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
 226                 return false;
 227
 228         tcp_len = tcp_hdrlen(skb);
 229         if (unlikely(tcp_len < sizeof(struct tcphdr) ||
 230                      skb->len < th_ofs + tcp_len))
 231                 return false;
 232
 233         return true;
 234 }
 235
 236 static bool udphdr_ok(struct sk_buff *skb)
 237 {
 238         return pskb_may_pull(skb, skb_transport_offset(skb) +
 239                                   sizeof(struct udphdr));
 240 }
 241
 242 static bool sctphdr_ok(struct sk_buff *skb)
 243 {
 244         return pskb_may_pull(skb, skb_transport_offset(skb) +
 245                                   sizeof(struct sctphdr));
 246 }
 247
 248 static bool icmphdr_ok(struct sk_buff *skb)
 249 {
 250         return pskb_may_pull(skb, skb_transport_offset(skb) +
 251                                   sizeof(struct icmphdr));
 252 }
 253
 254 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key)
 255 {
 256         unsigned int nh_ofs = skb_network_offset(skb);
 257         unsigned int nh_len;
 258         int payload_ofs;
 259         struct ipv6hdr *nh;
 260         uint8_t nexthdr;
 261         __be16 frag_off;
 262         int err;
 263
 264         err = check_header(skb, nh_ofs + sizeof(*nh));
 265         if (unlikely(err))
 266                 return err;
 267
 268         nh = ipv6_hdr(skb);
 269         nexthdr = nh->nexthdr;
 270         payload_ofs = (u8 *)(nh + 1) - skb->data;
 271
 272         key->ip.proto = NEXTHDR_NONE;
 273         key->ip.tos = ipv6_get_dsfield(nh);
 274         key->ip.ttl = nh->hop_limit;
 275         key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 276         key->ipv6.addr.src = nh->saddr;
 277         key->ipv6.addr.dst = nh->daddr;
 278
 279         payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
 280
 281         if (frag_off) {
 282                 if (frag_off & htons(~0x7))
 283                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 284                 else
 285                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 286         } else {
 287                 key->ip.frag = OVS_FRAG_TYPE_NONE;
 288         }
 289
 290         /* Delayed handling of error in ipv6_skip_exthdr() as it
 291          * always sets frag_off to a valid value which may be
 292          * used to set key->ip.frag above.
 293          */
 294         if (unlikely(payload_ofs < 0))
 295                 return -EPROTO;
 296
 297         nh_len = payload_ofs - nh_ofs;
 298         skb_set_transport_header(skb, nh_ofs + nh_len);
 299         key->ip.proto = nexthdr;
 300         return nh_len;
 301 }
 302
 303 static bool icmp6hdr_ok(struct sk_buff *skb)
 304 {
 305         return pskb_may_pull(skb, skb_transport_offset(skb) +
 306                                   sizeof(struct icmp6hdr));
 307 }
 308
 309 /**
 310  * Parse vlan tag from vlan header.
 311  * Returns ERROR on memory error.
 312  * Returns 0 if it encounters a non-vlan or incomplete packet.
 313  * Returns 1 after successfully parsing vlan tag.
 314  */
 315 static int parse_vlan_tag(struct sk_buff *skb, struct vlan_head *key_vh)
 316 {
 317         struct vlan_head *vh = (struct vlan_head *)skb->data;
 318
 319         if (likely(!eth_type_vlan(vh->tpid)))
 320                 return 0;
 321
 322         if (unlikely(skb->len < sizeof(struct vlan_head) + sizeof(__be16)))
 323                 return 0;
 324
 325         if (unlikely(!pskb_may_pull(skb, sizeof(struct vlan_head) +
 326                                  sizeof(__be16))))
 327                 return -ENOMEM;
 328
 329         vh = (struct vlan_head *)skb->data;
 330         key_vh->tci = vh->tci | htons(VLAN_TAG_PRESENT);
 331         key_vh->tpid = vh->tpid;
 332
 333         __skb_pull(skb, sizeof(struct vlan_head));
 334         return 1;
 335 }
 336
 337 static void clear_vlan(struct sw_flow_key *key)
 338 {
 339         key->eth.vlan.tci = 0;
 340         key->eth.vlan.tpid = 0;
 341         key->eth.cvlan.tci = 0;
 342         key->eth.cvlan.tpid = 0;
 343 }
 344
 345 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 346 {
 347         int res;
 348
 349         if (skb_vlan_tag_present(skb)) {
 350                 key->eth.vlan.tci = htons(skb->vlan_tci);
 351                 key->eth.vlan.tpid = skb->vlan_proto;
 352         } else {
 353                 /* Parse outer vlan tag in the non-accelerated case. */
 354                 res = parse_vlan_tag(skb, &key->eth.vlan);
 355                 if (res <= 0)
 356                         return res;
 357         }
 358
 359         /* Parse inner vlan tag. */
 360         res = parse_vlan_tag(skb, &key->eth.cvlan);
 361         if (res <= 0)
 362                 return res;
 363
 364         return 0;
 365 }
 366
 367 static __be16 parse_ethertype(struct sk_buff *skb)
 368 {
 369         struct llc_snap_hdr {
 370                 u8  dsap;  /* Always 0xAA */
 371                 u8  ssap;  /* Always 0xAA */
 372                 u8  ctrl;
 373                 u8  oui[3];
 374                 __be16 ethertype;
 375         };
 376         struct llc_snap_hdr *llc;
 377         __be16 proto;
 378
 379         proto = *(__be16 *) skb->data;
 380         __skb_pull(skb, sizeof(__be16));
 381
 382         if (eth_proto_is_802_3(proto))
 383                 return proto;
 384
 385         if (skb->len < sizeof(struct llc_snap_hdr))
 386                 return htons(ETH_P_802_2);
 387
 388         if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
 389                 return htons(0);
 390
 391         llc = (struct llc_snap_hdr *) skb->data;
 392         if (llc->dsap != LLC_SAP_SNAP ||
 393             llc->ssap != LLC_SAP_SNAP ||
 394             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
 395                 return htons(ETH_P_802_2);
 396
 397         __skb_pull(skb, sizeof(struct llc_snap_hdr));
 398
 399         if (eth_proto_is_802_3(llc->ethertype))
 400                 return llc->ethertype;
 401
 402         return htons(ETH_P_802_2);
 403 }
 404
 405 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
 406                         int nh_len)
 407 {
 408         struct icmp6hdr *icmp = icmp6_hdr(skb);
 409
 410         /* The ICMPv6 type and code fields use the 16-bit transport port
 411          * fields, so we need to store them in 16-bit network byte order.
 412          */
 413         key->tp.src = htons(icmp->icmp6_type);
 414         key->tp.dst = htons(icmp->icmp6_code);
 415         memset(&key->ipv6.nd, 0, sizeof(key->ipv6.nd));
 416
 417         if (icmp->icmp6_code == 0 &&
 418             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
 419              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 420                 int icmp_len = skb->len - skb_transport_offset(skb);
 421                 struct nd_msg *nd;
 422                 int offset;
 423
 424                 /* In order to process neighbor discovery options, we need the
 425                  * entire packet.
 426                  */
 427                 if (unlikely(icmp_len < sizeof(*nd)))
 428                         return 0;
 429
 430                 if (unlikely(skb_linearize(skb)))
 431                         return -ENOMEM;
 432
 433                 nd = (struct nd_msg *)skb_transport_header(skb);
 434                 key->ipv6.nd.target = nd->target;
 435
 436                 icmp_len -= sizeof(*nd);
 437                 offset = 0;
 438                 while (icmp_len >= 8) {
 439                         struct nd_opt_hdr *nd_opt =
 440                                  (struct nd_opt_hdr *)(nd->opt + offset);
 441                         int opt_len = nd_opt->nd_opt_len * 8;
 442
 443                         if (unlikely(!opt_len || opt_len > icmp_len))
 444                                 return 0;
 445
 446                         /* Store the link layer address if the appropriate
 447                          * option is provided.  It is considered an error if
 448                          * the same link layer option is specified twice.
 449                          */
 450                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
 451                             && opt_len == 8) {
 452                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
 453                                         goto invalid;
 454                                 ether_addr_copy(key->ipv6.nd.sll,
 455                                                 &nd->opt[offset+sizeof(*nd_opt)]);
 456                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
 457                                    && opt_len == 8) {
 458                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
 459                                         goto invalid;
 460                                 ether_addr_copy(key->ipv6.nd.tll,
 461                                                 &nd->opt[offset+sizeof(*nd_opt)]);
 462                         }
 463
 464                         icmp_len -= opt_len;
 465                         offset += opt_len;
 466                 }
 467         }
 468
 469         return 0;
 470
 471 invalid:
 472         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
 473         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
 474         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
 475
 476         return 0;
 477 }
 478
 479 /**
 480  * key_extract - extracts a flow key from an Ethernet frame.
 481  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 482  * Ethernet header
 483  * @key: output flow key
 484  *
 485  * The caller must ensure that skb->len >= ETH_HLEN.
 486  *
 487  * Returns 0 if successful, otherwise a negative errno value.
 488  *
 489  * Initializes @skb header fields as follows:
 490  *
 491  *    - skb->mac_header: the L2 header.
 492  *
 493  *    - skb->network_header: just past the L2 header, or just past the
 494  *      VLAN header, to the first byte of the L2 payload.
 495  *
 496  *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
 497  *      on output, then just past the IP header, if one is present and
 498  *      of a correct length, otherwise the same as skb->network_header.
 499  *      For other key->eth.type values it is left untouched.
 500  *
 501  *    - skb->protocol: the type of the data starting at skb->network_header.
 502  *      Equals to key->eth.type.
 503  */
 504 static int key_extract(struct sk_buff *skb, struct sw_flow_key *key)
 505 {
 506         int error;
 507         struct ethhdr *eth;
 508
 509         /* Flags are always used as part of stats */
 510         key->tp.flags = 0;
 511
 512         skb_reset_mac_header(skb);
 513
 514         /* Link layer. */
 515         clear_vlan(key);
 516         if (key->mac_proto == MAC_PROTO_NONE) {
 517                 if (unlikely(eth_type_vlan(skb->protocol)))
 518                         return -EINVAL;
 519
 520                 skb_reset_network_header(skb);
 521         } else {
 522                 eth = eth_hdr(skb);
 523                 ether_addr_copy(key->eth.src, eth->h_source);
 524                 ether_addr_copy(key->eth.dst, eth->h_dest);
 525
 526                 __skb_pull(skb, 2 * ETH_ALEN);
 527                 /* We are going to push all headers that we pull, so no need to
 528                 * update skb->csum here.
 529                 */
 530
 531                 if (unlikely(parse_vlan(skb, key)))
 532                         return -ENOMEM;
 533
 534                 skb->protocol = parse_ethertype(skb);
 535                 if (unlikely(skb->protocol == htons(0)))
 536                         return -ENOMEM;
 537
 538                 skb_reset_network_header(skb);
 539                 __skb_push(skb, skb->data - skb_mac_header(skb));
 540         }
 541         skb_reset_mac_len(skb);
 542         key->eth.type = skb->protocol;
 543
 544         /* Network layer. */
 545         if (key->eth.type == htons(ETH_P_IP)) {
 546                 struct iphdr *nh;
 547                 __be16 offset;
 548
 549                 error = check_iphdr(skb);
 550                 if (unlikely(error)) {
 551                         memset(&key->ip, 0, sizeof(key->ip));
 552                         memset(&key->ipv4, 0, sizeof(key->ipv4));
 553                         if (error == -EINVAL) {
 554                                 skb->transport_header = skb->network_header;
 555                                 error = 0;
 556                         }
 557                         return error;
 558                 }
 559
 560                 nh = ip_hdr(skb);
 561                 key->ipv4.addr.src = nh->saddr;
 562                 key->ipv4.addr.dst = nh->daddr;
 563
 564                 key->ip.proto = nh->protocol;
 565                 key->ip.tos = nh->tos;
 566                 key->ip.ttl = nh->ttl;
 567
 568                 offset = nh->frag_off & htons(IP_OFFSET);
 569                 if (offset) {
 570                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 571                         return 0;
 572                 }
 573                 if (nh->frag_off & htons(IP_MF) ||
 574                         skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 575                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 576                 else
 577                         key->ip.frag = OVS_FRAG_TYPE_NONE;
 578
 579                 /* Transport layer. */
 580                 if (key->ip.proto == IPPROTO_TCP) {
 581                         if (tcphdr_ok(skb)) {
 582                                 struct tcphdr *tcp = tcp_hdr(skb);
 583                                 key->tp.src = tcp->source;
 584                                 key->tp.dst = tcp->dest;
 585                                 key->tp.flags = TCP_FLAGS_BE16(tcp);
 586                         } else {
 587                                 memset(&key->tp, 0, sizeof(key->tp));
 588                         }
 589
 590                 } else if (key->ip.proto == IPPROTO_UDP) {
 591                         if (udphdr_ok(skb)) {
 592                                 struct udphdr *udp = udp_hdr(skb);
 593                                 key->tp.src = udp->source;
 594                                 key->tp.dst = udp->dest;
 595                         } else {
 596                                 memset(&key->tp, 0, sizeof(key->tp));
 597                         }
 598                 } else if (key->ip.proto == IPPROTO_SCTP) {
 599                         if (sctphdr_ok(skb)) {
 600                                 struct sctphdr *sctp = sctp_hdr(skb);
 601                                 key->tp.src = sctp->source;
 602                                 key->tp.dst = sctp->dest;
 603                         } else {
 604                                 memset(&key->tp, 0, sizeof(key->tp));
 605                         }
 606                 } else if (key->ip.proto == IPPROTO_ICMP) {
 607                         if (icmphdr_ok(skb)) {
 608                                 struct icmphdr *icmp = icmp_hdr(skb);
 609                                 /* The ICMP type and code fields use the 16-bit
 610                                  * transport port fields, so we need to store
 611                                  * them in 16-bit network byte order. */
 612                                 key->tp.src = htons(icmp->type);
 613                                 key->tp.dst = htons(icmp->code);
 614                         } else {
 615                                 memset(&key->tp, 0, sizeof(key->tp));
 616                         }
 617                 }
 618
 619         } else if (key->eth.type == htons(ETH_P_ARP) ||
 620                    key->eth.type == htons(ETH_P_RARP)) {
 621                 struct arp_eth_header *arp;
 622                 bool arp_available = arphdr_ok(skb);
 623
 624                 arp = (struct arp_eth_header *)skb_network_header(skb);
 625
 626                 if (arp_available &&
 627                     arp->ar_hrd == htons(ARPHRD_ETHER) &&
 628                     arp->ar_pro == htons(ETH_P_IP) &&
 629                     arp->ar_hln == ETH_ALEN &&
 630                     arp->ar_pln == 4) {
 631
 632                         /* We only match on the lower 8 bits of the opcode. */
 633                         if (ntohs(arp->ar_op) <= 0xff)
 634                                 key->ip.proto = ntohs(arp->ar_op);
 635                         else
 636                                 key->ip.proto = 0;
 637
 638                         memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
 639                         memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
 640                         ether_addr_copy(key->ipv4.arp.sha, arp->ar_sha);
 641                         ether_addr_copy(key->ipv4.arp.tha, arp->ar_tha);
 642                 } else {
 643                         memset(&key->ip, 0, sizeof(key->ip));
 644                         memset(&key->ipv4, 0, sizeof(key->ipv4));
 645                 }
 646         } else if (eth_p_mpls(key->eth.type)) {
 647                 size_t stack_len = MPLS_HLEN;
 648
 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 + stack_len);
 654                         if (unlikely(error))
 655                                 return 0;
 656
 657                         memcpy(&lse, skb_inner_network_header(skb), MPLS_HLEN);
 658
 659                         if (stack_len == MPLS_HLEN)
 660                                 memcpy(&key->mpls.top_lse, &lse, MPLS_HLEN);
 661
 662                         skb_set_inner_network_header(skb, skb->mac_len + stack_len);
 663                         if (lse & htonl(MPLS_LS_S_MASK))
 664                                 break;
 665
 666                         stack_len += MPLS_HLEN;
 667                 }
 668         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 669                 int nh_len;             /* IPv6 Header + Extensions */
 670
 671                 nh_len = parse_ipv6hdr(skb, key);
 672                 if (unlikely(nh_len < 0)) {
 673                         switch (nh_len) {
 674                         case -EINVAL:
 675                                 memset(&key->ip, 0, sizeof(key->ip));
 676                                 memset(&key->ipv6.addr, 0, sizeof(key->ipv6.addr));
 677                                 /* fall-through */
 678                         case -EPROTO:
 679                                 skb->transport_header = skb->network_header;
 680                                 error = 0;
 681                                 break;
 682                         default:
 683                                 error = nh_len;
 684                         }
 685                         return error;
 686                 }
 687
 688                 if (key->ip.frag == OVS_FRAG_TYPE_LATER)
 689                         return 0;
 690                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 691                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 692
 693                 /* Transport layer. */
 694                 if (key->ip.proto == NEXTHDR_TCP) {
 695                         if (tcphdr_ok(skb)) {
 696                                 struct tcphdr *tcp = tcp_hdr(skb);
 697                                 key->tp.src = tcp->source;
 698                                 key->tp.dst = tcp->dest;
 699                                 key->tp.flags = TCP_FLAGS_BE16(tcp);
 700                         } else {
 701                                 memset(&key->tp, 0, sizeof(key->tp));
 702                         }
 703                 } else if (key->ip.proto == NEXTHDR_UDP) {
 704                         if (udphdr_ok(skb)) {
 705                                 struct udphdr *udp = udp_hdr(skb);
 706                                 key->tp.src = udp->source;
 707                                 key->tp.dst = udp->dest;
 708                         } else {
 709                                 memset(&key->tp, 0, sizeof(key->tp));
 710                         }
 711                 } else if (key->ip.proto == NEXTHDR_SCTP) {
 712                         if (sctphdr_ok(skb)) {
 713                                 struct sctphdr *sctp = sctp_hdr(skb);
 714                                 key->tp.src = sctp->source;
 715                                 key->tp.dst = sctp->dest;
 716                         } else {
 717                                 memset(&key->tp, 0, sizeof(key->tp));
 718                         }
 719                 } else if (key->ip.proto == NEXTHDR_ICMP) {
 720                         if (icmp6hdr_ok(skb)) {
 721                                 error = parse_icmpv6(skb, key, nh_len);
 722                                 if (error)
 723                                         return error;
 724                         } else {
 725                                 memset(&key->tp, 0, sizeof(key->tp));
 726                         }
 727                 }
 728         }
 729         return 0;
 730 }
 731
 732 int ovs_flow_key_update(struct sk_buff *skb, struct sw_flow_key *key)
 733 {
 734         return key_extract(skb, key);
 735 }
 736
 737 static int key_extract_mac_proto(struct sk_buff *skb)
 738 {
 739         switch (skb->dev->type) {
 740         case ARPHRD_ETHER:
 741                 return MAC_PROTO_ETHERNET;
 742         case ARPHRD_NONE:
 743                 if (skb->protocol == htons(ETH_P_TEB))
 744                         return MAC_PROTO_ETHERNET;
 745                 return MAC_PROTO_NONE;
 746         }
 747         WARN_ON_ONCE(1);
 748         return -EINVAL;
 749 }
 750
 751 int ovs_flow_key_extract(const struct ip_tunnel_info *tun_info,
 752                          struct sk_buff *skb, struct sw_flow_key *key)
 753 {
 754         int res;
 755
 756         /* Extract metadata from packet. */
 757         if (tun_info) {
 758                 key->tun_proto = ip_tunnel_info_af(tun_info);
 759                 memcpy(&key->tun_key, &tun_info->key, sizeof(key->tun_key));
 760
 761                 if (tun_info->options_len) {
 762                         BUILD_BUG_ON((1 << (sizeof(tun_info->options_len) *
 763                                                    8)) - 1
 764                                         > sizeof(key->tun_opts));
 765
 766                         ip_tunnel_info_opts_get(TUN_METADATA_OPTS(key, tun_info->options_len),
 767                                                 tun_info);
 768                         key->tun_opts_len = tun_info->options_len;
 769                 } else {
 770                         key->tun_opts_len = 0;
 771                 }
 772         } else  {
 773                 key->tun_proto = 0;
 774                 key->tun_opts_len = 0;
 775                 memset(&key->tun_key, 0, sizeof(key->tun_key));
 776         }
 777
 778         key->phy.priority = skb->priority;
 779         key->phy.in_port = OVS_CB(skb)->input_vport->port_no;
 780         key->phy.skb_mark = skb->mark;
 781         ovs_ct_fill_key(skb, key);
 782         key->ovs_flow_hash = 0;
 783         res = key_extract_mac_proto(skb);
 784         if (res < 0)
 785                 return res;
 786         key->mac_proto = res;
 787         key->recirc_id = 0;
 788
 789         return key_extract(skb, key);
 790 }
 791
 792 int ovs_flow_key_extract_userspace(struct net *net, const struct nlattr *attr,
 793                                    struct sk_buff *skb,
 794                                    struct sw_flow_key *key, bool log)
 795 {
 796         int err;
 797
 798         /* Extract metadata from netlink attributes. */
 799         err = ovs_nla_get_flow_metadata(net, attr, key, log);
 800         if (err)
 801                 return err;
 802
 803         if (ovs_key_mac_proto(key) == MAC_PROTO_NONE) {
 804                 /* key_extract assumes that skb->protocol is set-up for
 805                  * layer 3 packets which is the case for other callers,
 806                  * in particular packets recieved from the network stack.
 807                  * Here the correct value can be set from the metadata
 808                  * extracted above.
 809                  */
 810                 skb->protocol = key->eth.type;
 811         } else {
 812                 struct ethhdr *eth;
 813
 814                 skb_reset_mac_header(skb);
 815                 eth = eth_hdr(skb);
 816
 817                 /* Normally, setting the skb 'protocol' field would be
 818                  * handled by a call to eth_type_trans(), but it assumes
 819                  * there's a sending device, which we may not have.
 820                  */
 821                 if (eth_proto_is_802_3(eth->h_proto))
 822                         skb->protocol = eth->h_proto;
 823                 else
 824                         skb->protocol = htons(ETH_P_802_2);
 825         }
 826
 827         return key_extract(skb, key);
 828 }