Pileus Git - ~andy/linux/blob - net/openvswitch/flow.c

   1 /*
   2  * Copyright (c) 2007-2011 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 "flow.h"
  20 #include "datapath.h"
  21 #include <linux/uaccess.h>
  22 #include <linux/netdevice.h>
  23 #include <linux/etherdevice.h>
  24 #include <linux/if_ether.h>
  25 #include <linux/if_vlan.h>
  26 #include <net/llc_pdu.h>
  27 #include <linux/kernel.h>
  28 #include <linux/jhash.h>
  29 #include <linux/jiffies.h>
  30 #include <linux/llc.h>
  31 #include <linux/module.h>
  32 #include <linux/in.h>
  33 #include <linux/rcupdate.h>
  34 #include <linux/if_arp.h>
  35 #include <linux/ip.h>
  36 #include <linux/ipv6.h>
  37 #include <linux/tcp.h>
  38 #include <linux/udp.h>
  39 #include <linux/icmp.h>
  40 #include <linux/icmpv6.h>
  41 #include <linux/rculist.h>
  42 #include <net/ip.h>
  43 #include <net/ipv6.h>
  44 #include <net/ndisc.h>
  45
  46 static struct kmem_cache *flow_cache;
  47
  48 static int check_header(struct sk_buff *skb, int len)
  49 {
  50         if (unlikely(skb->len < len))
  51                 return -EINVAL;
  52         if (unlikely(!pskb_may_pull(skb, len)))
  53                 return -ENOMEM;
  54         return 0;
  55 }
  56
  57 static bool arphdr_ok(struct sk_buff *skb)
  58 {
  59         return pskb_may_pull(skb, skb_network_offset(skb) +
  60                                   sizeof(struct arp_eth_header));
  61 }
  62
  63 static int check_iphdr(struct sk_buff *skb)
  64 {
  65         unsigned int nh_ofs = skb_network_offset(skb);
  66         unsigned int ip_len;
  67         int err;
  68
  69         err = check_header(skb, nh_ofs + sizeof(struct iphdr));
  70         if (unlikely(err))
  71                 return err;
  72
  73         ip_len = ip_hdrlen(skb);
  74         if (unlikely(ip_len < sizeof(struct iphdr) ||
  75                      skb->len < nh_ofs + ip_len))
  76                 return -EINVAL;
  77
  78         skb_set_transport_header(skb, nh_ofs + ip_len);
  79         return 0;
  80 }
  81
  82 static bool tcphdr_ok(struct sk_buff *skb)
  83 {
  84         int th_ofs = skb_transport_offset(skb);
  85         int tcp_len;
  86
  87         if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
  88                 return false;
  89
  90         tcp_len = tcp_hdrlen(skb);
  91         if (unlikely(tcp_len < sizeof(struct tcphdr) ||
  92                      skb->len < th_ofs + tcp_len))
  93                 return false;
  94
  95         return true;
  96 }
  97
  98 static bool udphdr_ok(struct sk_buff *skb)
  99 {
 100         return pskb_may_pull(skb, skb_transport_offset(skb) +
 101                                   sizeof(struct udphdr));
 102 }
 103
 104 static bool icmphdr_ok(struct sk_buff *skb)
 105 {
 106         return pskb_may_pull(skb, skb_transport_offset(skb) +
 107                                   sizeof(struct icmphdr));
 108 }
 109
 110 u64 ovs_flow_used_time(unsigned long flow_jiffies)
 111 {
 112         struct timespec cur_ts;
 113         u64 cur_ms, idle_ms;
 114
 115         ktime_get_ts(&cur_ts);
 116         idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
 117         cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
 118                  cur_ts.tv_nsec / NSEC_PER_MSEC;
 119
 120         return cur_ms - idle_ms;
 121 }
 122
 123 #define SW_FLOW_KEY_OFFSET(field)               \
 124         (offsetof(struct sw_flow_key, field) +  \
 125          FIELD_SIZEOF(struct sw_flow_key, field))
 126
 127 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key,
 128                          int *key_lenp)
 129 {
 130         unsigned int nh_ofs = skb_network_offset(skb);
 131         unsigned int nh_len;
 132         int payload_ofs;
 133         struct ipv6hdr *nh;
 134         uint8_t nexthdr;
 135         __be16 frag_off;
 136         int err;
 137
 138         *key_lenp = SW_FLOW_KEY_OFFSET(ipv6.label);
 139
 140         err = check_header(skb, nh_ofs + sizeof(*nh));
 141         if (unlikely(err))
 142                 return err;
 143
 144         nh = ipv6_hdr(skb);
 145         nexthdr = nh->nexthdr;
 146         payload_ofs = (u8 *)(nh + 1) - skb->data;
 147
 148         key->ip.proto = NEXTHDR_NONE;
 149         key->ip.tos = ipv6_get_dsfield(nh);
 150         key->ip.ttl = nh->hop_limit;
 151         key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 152         key->ipv6.addr.src = nh->saddr;
 153         key->ipv6.addr.dst = nh->daddr;
 154
 155         payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
 156         if (unlikely(payload_ofs < 0))
 157                 return -EINVAL;
 158
 159         if (frag_off) {
 160                 if (frag_off & htons(~0x7))
 161                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 162                 else
 163                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 164         }
 165
 166         nh_len = payload_ofs - nh_ofs;
 167         skb_set_transport_header(skb, nh_ofs + nh_len);
 168         key->ip.proto = nexthdr;
 169         return nh_len;
 170 }
 171
 172 static bool icmp6hdr_ok(struct sk_buff *skb)
 173 {
 174         return pskb_may_pull(skb, skb_transport_offset(skb) +
 175                                   sizeof(struct icmp6hdr));
 176 }
 177
 178 #define TCP_FLAGS_OFFSET 13
 179 #define TCP_FLAG_MASK 0x3f
 180
 181 void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb)
 182 {
 183         u8 tcp_flags = 0;
 184
 185         if ((flow->key.eth.type == htons(ETH_P_IP) ||
 186              flow->key.eth.type == htons(ETH_P_IPV6)) &&
 187             flow->key.ip.proto == IPPROTO_TCP &&
 188             likely(skb->len >= skb_transport_offset(skb) + sizeof(struct tcphdr))) {
 189                 u8 *tcp = (u8 *)tcp_hdr(skb);
 190                 tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
 191         }
 192
 193         spin_lock(&flow->lock);
 194         flow->used = jiffies;
 195         flow->packet_count++;
 196         flow->byte_count += skb->len;
 197         flow->tcp_flags |= tcp_flags;
 198         spin_unlock(&flow->lock);
 199 }
 200
 201 struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *actions)
 202 {
 203         int actions_len = nla_len(actions);
 204         struct sw_flow_actions *sfa;
 205
 206         if (actions_len > MAX_ACTIONS_BUFSIZE)
 207                 return ERR_PTR(-EINVAL);
 208
 209         sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
 210         if (!sfa)
 211                 return ERR_PTR(-ENOMEM);
 212
 213         sfa->actions_len = actions_len;
 214         nla_memcpy(sfa->actions, actions, actions_len);
 215         return sfa;
 216 }
 217
 218 struct sw_flow *ovs_flow_alloc(void)
 219 {
 220         struct sw_flow *flow;
 221
 222         flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
 223         if (!flow)
 224                 return ERR_PTR(-ENOMEM);
 225
 226         spin_lock_init(&flow->lock);
 227         flow->sf_acts = NULL;
 228
 229         return flow;
 230 }
 231
 232 static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
 233 {
 234         hash = jhash_1word(hash, table->hash_seed);
 235         return flex_array_get(table->buckets,
 236                                 (hash & (table->n_buckets - 1)));
 237 }
 238
 239 static struct flex_array *alloc_buckets(unsigned int n_buckets)
 240 {
 241         struct flex_array *buckets;
 242         int i, err;
 243
 244         buckets = flex_array_alloc(sizeof(struct hlist_head *),
 245                                    n_buckets, GFP_KERNEL);
 246         if (!buckets)
 247                 return NULL;
 248
 249         err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
 250         if (err) {
 251                 flex_array_free(buckets);
 252                 return NULL;
 253         }
 254
 255         for (i = 0; i < n_buckets; i++)
 256                 INIT_HLIST_HEAD((struct hlist_head *)
 257                                         flex_array_get(buckets, i));
 258
 259         return buckets;
 260 }
 261
 262 static void free_buckets(struct flex_array *buckets)
 263 {
 264         flex_array_free(buckets);
 265 }
 266
 267 struct flow_table *ovs_flow_tbl_alloc(int new_size)
 268 {
 269         struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
 270
 271         if (!table)
 272                 return NULL;
 273
 274         table->buckets = alloc_buckets(new_size);
 275
 276         if (!table->buckets) {
 277                 kfree(table);
 278                 return NULL;
 279         }
 280         table->n_buckets = new_size;
 281         table->count = 0;
 282         table->node_ver = 0;
 283         table->keep_flows = false;
 284         get_random_bytes(&table->hash_seed, sizeof(u32));
 285
 286         return table;
 287 }
 288
 289 void ovs_flow_tbl_destroy(struct flow_table *table)
 290 {
 291         int i;
 292
 293         if (!table)
 294                 return;
 295
 296         if (table->keep_flows)
 297                 goto skip_flows;
 298
 299         for (i = 0; i < table->n_buckets; i++) {
 300                 struct sw_flow *flow;
 301                 struct hlist_head *head = flex_array_get(table->buckets, i);
 302                 struct hlist_node *n;
 303                 int ver = table->node_ver;
 304
 305                 hlist_for_each_entry_safe(flow, n, head, hash_node[ver]) {
 306                         hlist_del_rcu(&flow->hash_node[ver]);
 307                         ovs_flow_free(flow);
 308                 }
 309         }
 310
 311 skip_flows:
 312         free_buckets(table->buckets);
 313         kfree(table);
 314 }
 315
 316 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
 317 {
 318         struct flow_table *table = container_of(rcu, struct flow_table, rcu);
 319
 320         ovs_flow_tbl_destroy(table);
 321 }
 322
 323 void ovs_flow_tbl_deferred_destroy(struct flow_table *table)
 324 {
 325         if (!table)
 326                 return;
 327
 328         call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
 329 }
 330
 331 struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
 332 {
 333         struct sw_flow *flow;
 334         struct hlist_head *head;
 335         int ver;
 336         int i;
 337
 338         ver = table->node_ver;
 339         while (*bucket < table->n_buckets) {
 340                 i = 0;
 341                 head = flex_array_get(table->buckets, *bucket);
 342                 hlist_for_each_entry_rcu(flow, head, hash_node[ver]) {
 343                         if (i < *last) {
 344                                 i++;
 345                                 continue;
 346                         }
 347                         *last = i + 1;
 348                         return flow;
 349                 }
 350                 (*bucket)++;
 351                 *last = 0;
 352         }
 353
 354         return NULL;
 355 }
 356
 357 static void flow_table_copy_flows(struct flow_table *old, struct flow_table *new)
 358 {
 359         int old_ver;
 360         int i;
 361
 362         old_ver = old->node_ver;
 363         new->node_ver = !old_ver;
 364
 365         /* Insert in new table. */
 366         for (i = 0; i < old->n_buckets; i++) {
 367                 struct sw_flow *flow;
 368                 struct hlist_head *head;
 369
 370                 head = flex_array_get(old->buckets, i);
 371
 372                 hlist_for_each_entry(flow, head, hash_node[old_ver])
 373                         ovs_flow_tbl_insert(new, flow);
 374         }
 375         old->keep_flows = true;
 376 }
 377
 378 static struct flow_table *__flow_tbl_rehash(struct flow_table *table, int n_buckets)
 379 {
 380         struct flow_table *new_table;
 381
 382         new_table = ovs_flow_tbl_alloc(n_buckets);
 383         if (!new_table)
 384                 return ERR_PTR(-ENOMEM);
 385
 386         flow_table_copy_flows(table, new_table);
 387
 388         return new_table;
 389 }
 390
 391 struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table)
 392 {
 393         return __flow_tbl_rehash(table, table->n_buckets);
 394 }
 395
 396 struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
 397 {
 398         return __flow_tbl_rehash(table, table->n_buckets * 2);
 399 }
 400
 401 void ovs_flow_free(struct sw_flow *flow)
 402 {
 403         if (unlikely(!flow))
 404                 return;
 405
 406         kfree((struct sf_flow_acts __force *)flow->sf_acts);
 407         kmem_cache_free(flow_cache, flow);
 408 }
 409
 410 /* RCU callback used by ovs_flow_deferred_free. */
 411 static void rcu_free_flow_callback(struct rcu_head *rcu)
 412 {
 413         struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
 414
 415         ovs_flow_free(flow);
 416 }
 417
 418 /* Schedules 'flow' to be freed after the next RCU grace period.
 419  * The caller must hold rcu_read_lock for this to be sensible. */
 420 void ovs_flow_deferred_free(struct sw_flow *flow)
 421 {
 422         call_rcu(&flow->rcu, rcu_free_flow_callback);
 423 }
 424
 425 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
 426  * The caller must hold rcu_read_lock for this to be sensible. */
 427 void ovs_flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
 428 {
 429         kfree_rcu(sf_acts, rcu);
 430 }
 431
 432 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 433 {
 434         struct qtag_prefix {
 435                 __be16 eth_type; /* ETH_P_8021Q */
 436                 __be16 tci;
 437         };
 438         struct qtag_prefix *qp;
 439
 440         if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
 441                 return 0;
 442
 443         if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
 444                                          sizeof(__be16))))
 445                 return -ENOMEM;
 446
 447         qp = (struct qtag_prefix *) skb->data;
 448         key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
 449         __skb_pull(skb, sizeof(struct qtag_prefix));
 450
 451         return 0;
 452 }
 453
 454 static __be16 parse_ethertype(struct sk_buff *skb)
 455 {
 456         struct llc_snap_hdr {
 457                 u8  dsap;  /* Always 0xAA */
 458                 u8  ssap;  /* Always 0xAA */
 459                 u8  ctrl;
 460                 u8  oui[3];
 461                 __be16 ethertype;
 462         };
 463         struct llc_snap_hdr *llc;
 464         __be16 proto;
 465
 466         proto = *(__be16 *) skb->data;
 467         __skb_pull(skb, sizeof(__be16));
 468
 469         if (ntohs(proto) >= ETH_P_802_3_MIN)
 470                 return proto;
 471
 472         if (skb->len < sizeof(struct llc_snap_hdr))
 473                 return htons(ETH_P_802_2);
 474
 475         if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
 476                 return htons(0);
 477
 478         llc = (struct llc_snap_hdr *) skb->data;
 479         if (llc->dsap != LLC_SAP_SNAP ||
 480             llc->ssap != LLC_SAP_SNAP ||
 481             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
 482                 return htons(ETH_P_802_2);
 483
 484         __skb_pull(skb, sizeof(struct llc_snap_hdr));
 485
 486         if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN)
 487                 return llc->ethertype;
 488
 489         return htons(ETH_P_802_2);
 490 }
 491
 492 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
 493                         int *key_lenp, int nh_len)
 494 {
 495         struct icmp6hdr *icmp = icmp6_hdr(skb);
 496         int error = 0;
 497         int key_len;
 498
 499         /* The ICMPv6 type and code fields use the 16-bit transport port
 500          * fields, so we need to store them in 16-bit network byte order.
 501          */
 502         key->ipv6.tp.src = htons(icmp->icmp6_type);
 503         key->ipv6.tp.dst = htons(icmp->icmp6_code);
 504         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 505
 506         if (icmp->icmp6_code == 0 &&
 507             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
 508              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 509                 int icmp_len = skb->len - skb_transport_offset(skb);
 510                 struct nd_msg *nd;
 511                 int offset;
 512
 513                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 514
 515                 /* In order to process neighbor discovery options, we need the
 516                  * entire packet.
 517                  */
 518                 if (unlikely(icmp_len < sizeof(*nd)))
 519                         goto out;
 520                 if (unlikely(skb_linearize(skb))) {
 521                         error = -ENOMEM;
 522                         goto out;
 523                 }
 524
 525                 nd = (struct nd_msg *)skb_transport_header(skb);
 526                 key->ipv6.nd.target = nd->target;
 527                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 528
 529                 icmp_len -= sizeof(*nd);
 530                 offset = 0;
 531                 while (icmp_len >= 8) {
 532                         struct nd_opt_hdr *nd_opt =
 533                                  (struct nd_opt_hdr *)(nd->opt + offset);
 534                         int opt_len = nd_opt->nd_opt_len * 8;
 535
 536                         if (unlikely(!opt_len || opt_len > icmp_len))
 537                                 goto invalid;
 538
 539                         /* Store the link layer address if the appropriate
 540                          * option is provided.  It is considered an error if
 541                          * the same link layer option is specified twice.
 542                          */
 543                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
 544                             && opt_len == 8) {
 545                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
 546                                         goto invalid;
 547                                 memcpy(key->ipv6.nd.sll,
 548                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 549                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
 550                                    && opt_len == 8) {
 551                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
 552                                         goto invalid;
 553                                 memcpy(key->ipv6.nd.tll,
 554                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 555                         }
 556
 557                         icmp_len -= opt_len;
 558                         offset += opt_len;
 559                 }
 560         }
 561
 562         goto out;
 563
 564 invalid:
 565         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
 566         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
 567         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
 568
 569 out:
 570         *key_lenp = key_len;
 571         return error;
 572 }
 573
 574 /**
 575  * ovs_flow_extract - extracts a flow key from an Ethernet frame.
 576  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 577  * Ethernet header
 578  * @in_port: port number on which @skb was received.
 579  * @key: output flow key
 580  * @key_lenp: length of output flow key
 581  *
 582  * The caller must ensure that skb->len >= ETH_HLEN.
 583  *
 584  * Returns 0 if successful, otherwise a negative errno value.
 585  *
 586  * Initializes @skb header pointers as follows:
 587  *
 588  *    - skb->mac_header: the Ethernet header.
 589  *
 590  *    - skb->network_header: just past the Ethernet header, or just past the
 591  *      VLAN header, to the first byte of the Ethernet payload.
 592  *
 593  *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
 594  *      on output, then just past the IP header, if one is present and
 595  *      of a correct length, otherwise the same as skb->network_header.
 596  *      For other key->eth.type values it is left untouched.
 597  */
 598 int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
 599                  int *key_lenp)
 600 {
 601         int error = 0;
 602         int key_len = SW_FLOW_KEY_OFFSET(eth);
 603         struct ethhdr *eth;
 604
 605         memset(key, 0, sizeof(*key));
 606
 607         key->phy.priority = skb->priority;
 608         key->phy.in_port = in_port;
 609         key->phy.skb_mark = skb->mark;
 610
 611         skb_reset_mac_header(skb);
 612
 613         /* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
 614          * header in the linear data area.
 615          */
 616         eth = eth_hdr(skb);
 617         memcpy(key->eth.src, eth->h_source, ETH_ALEN);
 618         memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
 619
 620         __skb_pull(skb, 2 * ETH_ALEN);
 621         /* We are going to push all headers that we pull, so no need to
 622          * update skb->csum here.
 623          */
 624
 625         if (vlan_tx_tag_present(skb))
 626                 key->eth.tci = htons(skb->vlan_tci);
 627         else if (eth->h_proto == htons(ETH_P_8021Q))
 628                 if (unlikely(parse_vlan(skb, key)))
 629                         return -ENOMEM;
 630
 631         key->eth.type = parse_ethertype(skb);
 632         if (unlikely(key->eth.type == htons(0)))
 633                 return -ENOMEM;
 634
 635         skb_reset_network_header(skb);
 636         __skb_push(skb, skb->data - skb_mac_header(skb));
 637
 638         /* Network layer. */
 639         if (key->eth.type == htons(ETH_P_IP)) {
 640                 struct iphdr *nh;
 641                 __be16 offset;
 642
 643                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
 644
 645                 error = check_iphdr(skb);
 646                 if (unlikely(error)) {
 647                         if (error == -EINVAL) {
 648                                 skb->transport_header = skb->network_header;
 649                                 error = 0;
 650                         }
 651                         goto out;
 652                 }
 653
 654                 nh = ip_hdr(skb);
 655                 key->ipv4.addr.src = nh->saddr;
 656                 key->ipv4.addr.dst = nh->daddr;
 657
 658                 key->ip.proto = nh->protocol;
 659                 key->ip.tos = nh->tos;
 660                 key->ip.ttl = nh->ttl;
 661
 662                 offset = nh->frag_off & htons(IP_OFFSET);
 663                 if (offset) {
 664                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 665                         goto out;
 666                 }
 667                 if (nh->frag_off & htons(IP_MF) ||
 668                          skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 669                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 670
 671                 /* Transport layer. */
 672                 if (key->ip.proto == IPPROTO_TCP) {
 673                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 674                         if (tcphdr_ok(skb)) {
 675                                 struct tcphdr *tcp = tcp_hdr(skb);
 676                                 key->ipv4.tp.src = tcp->source;
 677                                 key->ipv4.tp.dst = tcp->dest;
 678                         }
 679                 } else if (key->ip.proto == IPPROTO_UDP) {
 680                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 681                         if (udphdr_ok(skb)) {
 682                                 struct udphdr *udp = udp_hdr(skb);
 683                                 key->ipv4.tp.src = udp->source;
 684                                 key->ipv4.tp.dst = udp->dest;
 685                         }
 686                 } else if (key->ip.proto == IPPROTO_ICMP) {
 687                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 688                         if (icmphdr_ok(skb)) {
 689                                 struct icmphdr *icmp = icmp_hdr(skb);
 690                                 /* The ICMP type and code fields use the 16-bit
 691                                  * transport port fields, so we need to store
 692                                  * them in 16-bit network byte order. */
 693                                 key->ipv4.tp.src = htons(icmp->type);
 694                                 key->ipv4.tp.dst = htons(icmp->code);
 695                         }
 696                 }
 697
 698         } else if ((key->eth.type == htons(ETH_P_ARP) ||
 699                    key->eth.type == htons(ETH_P_RARP)) && arphdr_ok(skb)) {
 700                 struct arp_eth_header *arp;
 701
 702                 arp = (struct arp_eth_header *)skb_network_header(skb);
 703
 704                 if (arp->ar_hrd == htons(ARPHRD_ETHER)
 705                                 && arp->ar_pro == htons(ETH_P_IP)
 706                                 && arp->ar_hln == ETH_ALEN
 707                                 && arp->ar_pln == 4) {
 708
 709                         /* We only match on the lower 8 bits of the opcode. */
 710                         if (ntohs(arp->ar_op) <= 0xff)
 711                                 key->ip.proto = ntohs(arp->ar_op);
 712                         memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
 713                         memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
 714                         memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
 715                         memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
 716                         key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
 717                 }
 718         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 719                 int nh_len;             /* IPv6 Header + Extensions */
 720
 721                 nh_len = parse_ipv6hdr(skb, key, &key_len);
 722                 if (unlikely(nh_len < 0)) {
 723                         if (nh_len == -EINVAL)
 724                                 skb->transport_header = skb->network_header;
 725                         else
 726                                 error = nh_len;
 727                         goto out;
 728                 }
 729
 730                 if (key->ip.frag == OVS_FRAG_TYPE_LATER)
 731                         goto out;
 732                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 733                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 734
 735                 /* Transport layer. */
 736                 if (key->ip.proto == NEXTHDR_TCP) {
 737                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 738                         if (tcphdr_ok(skb)) {
 739                                 struct tcphdr *tcp = tcp_hdr(skb);
 740                                 key->ipv6.tp.src = tcp->source;
 741                                 key->ipv6.tp.dst = tcp->dest;
 742                         }
 743                 } else if (key->ip.proto == NEXTHDR_UDP) {
 744                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 745                         if (udphdr_ok(skb)) {
 746                                 struct udphdr *udp = udp_hdr(skb);
 747                                 key->ipv6.tp.src = udp->source;
 748                                 key->ipv6.tp.dst = udp->dest;
 749                         }
 750                 } else if (key->ip.proto == NEXTHDR_ICMP) {
 751                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 752                         if (icmp6hdr_ok(skb)) {
 753                                 error = parse_icmpv6(skb, key, &key_len, nh_len);
 754                                 if (error < 0)
 755                                         goto out;
 756                         }
 757                 }
 758         }
 759
 760 out:
 761         *key_lenp = key_len;
 762         return error;
 763 }
 764
 765 u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len)
 766 {
 767         return jhash2((u32 *)key, DIV_ROUND_UP(key_len, sizeof(u32)), 0);
 768 }
 769
 770 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
 771                                 struct sw_flow_key *key, int key_len)
 772 {
 773         struct sw_flow *flow;
 774         struct hlist_head *head;
 775         u32 hash;
 776
 777         hash = ovs_flow_hash(key, key_len);
 778
 779         head = find_bucket(table, hash);
 780         hlist_for_each_entry_rcu(flow, head, hash_node[table->node_ver]) {
 781
 782                 if (flow->hash == hash &&
 783                     !memcmp(&flow->key, key, key_len)) {
 784                         return flow;
 785                 }
 786         }
 787         return NULL;
 788 }
 789
 790 void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
 791 {
 792         struct hlist_head *head;
 793
 794         head = find_bucket(table, flow->hash);
 795         hlist_add_head_rcu(&flow->hash_node[table->node_ver], head);
 796         table->count++;
 797 }
 798
 799 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
 800 {
 801         BUG_ON(table->count == 0);
 802         hlist_del_rcu(&flow->hash_node[table->node_ver]);
 803         table->count--;
 804 }
 805
 806 /* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
 807 const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
 808         [OVS_KEY_ATTR_ENCAP] = -1,
 809         [OVS_KEY_ATTR_PRIORITY] = sizeof(u32),
 810         [OVS_KEY_ATTR_IN_PORT] = sizeof(u32),
 811         [OVS_KEY_ATTR_SKB_MARK] = sizeof(u32),
 812         [OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
 813         [OVS_KEY_ATTR_VLAN] = sizeof(__be16),
 814         [OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
 815         [OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
 816         [OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
 817         [OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
 818         [OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
 819         [OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
 820         [OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
 821         [OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
 822         [OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
 823 };
 824
 825 static int ipv4_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 826                                   const struct nlattr *a[], u32 *attrs)
 827 {
 828         const struct ovs_key_icmp *icmp_key;
 829         const struct ovs_key_tcp *tcp_key;
 830         const struct ovs_key_udp *udp_key;
 831
 832         switch (swkey->ip.proto) {
 833         case IPPROTO_TCP:
 834                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 835                         return -EINVAL;
 836                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 837
 838                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 839                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 840                 swkey->ipv4.tp.src = tcp_key->tcp_src;
 841                 swkey->ipv4.tp.dst = tcp_key->tcp_dst;
 842                 break;
 843
 844         case IPPROTO_UDP:
 845                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 846                         return -EINVAL;
 847                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 848
 849                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 850                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 851                 swkey->ipv4.tp.src = udp_key->udp_src;
 852                 swkey->ipv4.tp.dst = udp_key->udp_dst;
 853                 break;
 854
 855         case IPPROTO_ICMP:
 856                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMP)))
 857                         return -EINVAL;
 858                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
 859
 860                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 861                 icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
 862                 swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
 863                 swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
 864                 break;
 865         }
 866
 867         return 0;
 868 }
 869
 870 static int ipv6_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 871                                   const struct nlattr *a[], u32 *attrs)
 872 {
 873         const struct ovs_key_icmpv6 *icmpv6_key;
 874         const struct ovs_key_tcp *tcp_key;
 875         const struct ovs_key_udp *udp_key;
 876
 877         switch (swkey->ip.proto) {
 878         case IPPROTO_TCP:
 879                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 880                         return -EINVAL;
 881                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 882
 883                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 884                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 885                 swkey->ipv6.tp.src = tcp_key->tcp_src;
 886                 swkey->ipv6.tp.dst = tcp_key->tcp_dst;
 887                 break;
 888
 889         case IPPROTO_UDP:
 890                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 891                         return -EINVAL;
 892                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 893
 894                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 895                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 896                 swkey->ipv6.tp.src = udp_key->udp_src;
 897                 swkey->ipv6.tp.dst = udp_key->udp_dst;
 898                 break;
 899
 900         case IPPROTO_ICMPV6:
 901                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMPV6)))
 902                         return -EINVAL;
 903                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
 904
 905                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 906                 icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
 907                 swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
 908                 swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
 909
 910                 if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
 911                     swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 912                         const struct ovs_key_nd *nd_key;
 913
 914                         if (!(*attrs & (1 << OVS_KEY_ATTR_ND)))
 915                                 return -EINVAL;
 916                         *attrs &= ~(1 << OVS_KEY_ATTR_ND);
 917
 918                         *key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 919                         nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
 920                         memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
 921                                sizeof(swkey->ipv6.nd.target));
 922                         memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
 923                         memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
 924                 }
 925                 break;
 926         }
 927
 928         return 0;
 929 }
 930
 931 static int parse_flow_nlattrs(const struct nlattr *attr,
 932                               const struct nlattr *a[], u32 *attrsp)
 933 {
 934         const struct nlattr *nla;
 935         u32 attrs;
 936         int rem;
 937
 938         attrs = 0;
 939         nla_for_each_nested(nla, attr, rem) {
 940                 u16 type = nla_type(nla);
 941                 int expected_len;
 942
 943                 if (type > OVS_KEY_ATTR_MAX || attrs & (1 << type))
 944                         return -EINVAL;
 945
 946                 expected_len = ovs_key_lens[type];
 947                 if (nla_len(nla) != expected_len && expected_len != -1)
 948                         return -EINVAL;
 949
 950                 attrs |= 1 << type;
 951                 a[type] = nla;
 952         }
 953         if (rem)
 954                 return -EINVAL;
 955
 956         *attrsp = attrs;
 957         return 0;
 958 }
 959
 960 /**
 961  * ovs_flow_from_nlattrs - parses Netlink attributes into a flow key.
 962  * @swkey: receives the extracted flow key.
 963  * @key_lenp: number of bytes used in @swkey.
 964  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
 965  * sequence.
 966  */
 967 int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
 968                       const struct nlattr *attr)
 969 {
 970         const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
 971         const struct ovs_key_ethernet *eth_key;
 972         int key_len;
 973         u32 attrs;
 974         int err;
 975
 976         memset(swkey, 0, sizeof(struct sw_flow_key));
 977         key_len = SW_FLOW_KEY_OFFSET(eth);
 978
 979         err = parse_flow_nlattrs(attr, a, &attrs);
 980         if (err)
 981                 return err;
 982
 983         /* Metadata attributes. */
 984         if (attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
 985                 swkey->phy.priority = nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]);
 986                 attrs &= ~(1 << OVS_KEY_ATTR_PRIORITY);
 987         }
 988         if (attrs & (1 << OVS_KEY_ATTR_IN_PORT)) {
 989                 u32 in_port = nla_get_u32(a[OVS_KEY_ATTR_IN_PORT]);
 990                 if (in_port >= DP_MAX_PORTS)
 991                         return -EINVAL;
 992                 swkey->phy.in_port = in_port;
 993                 attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
 994         } else {
 995                 swkey->phy.in_port = DP_MAX_PORTS;
 996         }
 997         if (attrs & (1 << OVS_KEY_ATTR_SKB_MARK)) {
 998                 swkey->phy.skb_mark = nla_get_u32(a[OVS_KEY_ATTR_SKB_MARK]);
 999                 attrs &= ~(1 << OVS_KEY_ATTR_SKB_MARK);
1000         }
1001
1002         /* Data attributes. */
1003         if (!(attrs & (1 << OVS_KEY_ATTR_ETHERNET)))
1004                 return -EINVAL;
1005         attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
1006
1007         eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
1008         memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
1009         memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
1010
1011         if (attrs & (1u << OVS_KEY_ATTR_ETHERTYPE) &&
1012             nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q)) {
1013                 const struct nlattr *encap;
1014                 __be16 tci;
1015
1016                 if (attrs != ((1 << OVS_KEY_ATTR_VLAN) |
1017                               (1 << OVS_KEY_ATTR_ETHERTYPE) |
1018                               (1 << OVS_KEY_ATTR_ENCAP)))
1019                         return -EINVAL;
1020
1021                 encap = a[OVS_KEY_ATTR_ENCAP];
1022                 tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
1023                 if (tci & htons(VLAN_TAG_PRESENT)) {
1024                         swkey->eth.tci = tci;
1025
1026                         err = parse_flow_nlattrs(encap, a, &attrs);
1027                         if (err)
1028                                 return err;
1029                 } else if (!tci) {
1030                         /* Corner case for truncated 802.1Q header. */
1031                         if (nla_len(encap))
1032                                 return -EINVAL;
1033
1034                         swkey->eth.type = htons(ETH_P_8021Q);
1035                         *key_lenp = key_len;
1036                         return 0;
1037                 } else {
1038                         return -EINVAL;
1039                 }
1040         }
1041
1042         if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
1043                 swkey->eth.type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
1044                 if (ntohs(swkey->eth.type) < ETH_P_802_3_MIN)
1045                         return -EINVAL;
1046                 attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
1047         } else {
1048                 swkey->eth.type = htons(ETH_P_802_2);
1049         }
1050
1051         if (swkey->eth.type == htons(ETH_P_IP)) {
1052                 const struct ovs_key_ipv4 *ipv4_key;
1053
1054                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV4)))
1055                         return -EINVAL;
1056                 attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
1057
1058                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
1059                 ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
1060                 if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
1061                         return -EINVAL;
1062                 swkey->ip.proto = ipv4_key->ipv4_proto;
1063                 swkey->ip.tos = ipv4_key->ipv4_tos;
1064                 swkey->ip.ttl = ipv4_key->ipv4_ttl;
1065                 swkey->ip.frag = ipv4_key->ipv4_frag;
1066                 swkey->ipv4.addr.src = ipv4_key->ipv4_src;
1067                 swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
1068
1069                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1070                         err = ipv4_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1071                         if (err)
1072                                 return err;
1073                 }
1074         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1075                 const struct ovs_key_ipv6 *ipv6_key;
1076
1077                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV6)))
1078                         return -EINVAL;
1079                 attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
1080
1081                 key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
1082                 ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
1083                 if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
1084                         return -EINVAL;
1085                 swkey->ipv6.label = ipv6_key->ipv6_label;
1086                 swkey->ip.proto = ipv6_key->ipv6_proto;
1087                 swkey->ip.tos = ipv6_key->ipv6_tclass;
1088                 swkey->ip.ttl = ipv6_key->ipv6_hlimit;
1089                 swkey->ip.frag = ipv6_key->ipv6_frag;
1090                 memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
1091                        sizeof(swkey->ipv6.addr.src));
1092                 memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
1093                        sizeof(swkey->ipv6.addr.dst));
1094
1095                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1096                         err = ipv6_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1097                         if (err)
1098                                 return err;
1099                 }
1100         } else if (swkey->eth.type == htons(ETH_P_ARP) ||
1101                    swkey->eth.type == htons(ETH_P_RARP)) {
1102                 const struct ovs_key_arp *arp_key;
1103
1104                 if (!(attrs & (1 << OVS_KEY_ATTR_ARP)))
1105                         return -EINVAL;
1106                 attrs &= ~(1 << OVS_KEY_ATTR_ARP);
1107
1108                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
1109                 arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
1110                 swkey->ipv4.addr.src = arp_key->arp_sip;
1111                 swkey->ipv4.addr.dst = arp_key->arp_tip;
1112                 if (arp_key->arp_op & htons(0xff00))
1113                         return -EINVAL;
1114                 swkey->ip.proto = ntohs(arp_key->arp_op);
1115                 memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
1116                 memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
1117         }
1118
1119         if (attrs)
1120                 return -EINVAL;
1121         *key_lenp = key_len;
1122
1123         return 0;
1124 }
1125
1126 /**
1127  * ovs_flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
1128  * @flow: Receives extracted in_port, priority, tun_key and skb_mark.
1129  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1130  * sequence.
1131  *
1132  * This parses a series of Netlink attributes that form a flow key, which must
1133  * take the same form accepted by flow_from_nlattrs(), but only enough of it to
1134  * get the metadata, that is, the parts of the flow key that cannot be
1135  * extracted from the packet itself.
1136  */
1137 int ovs_flow_metadata_from_nlattrs(struct sw_flow *flow,
1138                                    const struct nlattr *attr)
1139 {
1140         const struct nlattr *nla;
1141         int rem;
1142
1143         flow->key.phy.in_port = DP_MAX_PORTS;
1144         flow->key.phy.priority = 0;
1145         flow->key.phy.skb_mark = 0;
1146
1147         nla_for_each_nested(nla, attr, rem) {
1148                 int type = nla_type(nla);
1149
1150                 if (type <= OVS_KEY_ATTR_MAX && ovs_key_lens[type] > 0) {
1151                         if (nla_len(nla) != ovs_key_lens[type])
1152                                 return -EINVAL;
1153
1154                         switch (type) {
1155                         case OVS_KEY_ATTR_PRIORITY:
1156                                 flow->key.phy.priority = nla_get_u32(nla);
1157                                 break;
1158
1159                         case OVS_KEY_ATTR_IN_PORT:
1160                                 if (nla_get_u32(nla) >= DP_MAX_PORTS)
1161                                         return -EINVAL;
1162                                 flow->key.phy.in_port = nla_get_u32(nla);
1163                                 break;
1164
1165                         case OVS_KEY_ATTR_SKB_MARK:
1166                                 flow->key.phy.skb_mark = nla_get_u32(nla);
1167                                 break;
1168                         }
1169                 }
1170         }
1171         if (rem)
1172                 return -EINVAL;
1173         return 0;
1174 }
1175
1176 int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
1177 {
1178         struct ovs_key_ethernet *eth_key;
1179         struct nlattr *nla, *encap;
1180
1181         if (swkey->phy.priority &&
1182             nla_put_u32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority))
1183                 goto nla_put_failure;
1184
1185         if (swkey->phy.in_port != DP_MAX_PORTS &&
1186             nla_put_u32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port))
1187                 goto nla_put_failure;
1188
1189         if (swkey->phy.skb_mark &&
1190             nla_put_u32(skb, OVS_KEY_ATTR_SKB_MARK, swkey->phy.skb_mark))
1191                 goto nla_put_failure;
1192
1193         nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
1194         if (!nla)
1195                 goto nla_put_failure;
1196         eth_key = nla_data(nla);
1197         memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
1198         memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
1199
1200         if (swkey->eth.tci || swkey->eth.type == htons(ETH_P_8021Q)) {
1201                 if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, htons(ETH_P_8021Q)) ||
1202                     nla_put_be16(skb, OVS_KEY_ATTR_VLAN, swkey->eth.tci))
1203                         goto nla_put_failure;
1204                 encap = nla_nest_start(skb, OVS_KEY_ATTR_ENCAP);
1205                 if (!swkey->eth.tci)
1206                         goto unencap;
1207         } else {
1208                 encap = NULL;
1209         }
1210
1211         if (swkey->eth.type == htons(ETH_P_802_2))
1212                 goto unencap;
1213
1214         if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type))
1215                 goto nla_put_failure;
1216
1217         if (swkey->eth.type == htons(ETH_P_IP)) {
1218                 struct ovs_key_ipv4 *ipv4_key;
1219
1220                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
1221                 if (!nla)
1222                         goto nla_put_failure;
1223                 ipv4_key = nla_data(nla);
1224                 ipv4_key->ipv4_src = swkey->ipv4.addr.src;
1225                 ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
1226                 ipv4_key->ipv4_proto = swkey->ip.proto;
1227                 ipv4_key->ipv4_tos = swkey->ip.tos;
1228                 ipv4_key->ipv4_ttl = swkey->ip.ttl;
1229                 ipv4_key->ipv4_frag = swkey->ip.frag;
1230         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1231                 struct ovs_key_ipv6 *ipv6_key;
1232
1233                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
1234                 if (!nla)
1235                         goto nla_put_failure;
1236                 ipv6_key = nla_data(nla);
1237                 memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
1238                                 sizeof(ipv6_key->ipv6_src));
1239                 memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
1240                                 sizeof(ipv6_key->ipv6_dst));
1241                 ipv6_key->ipv6_label = swkey->ipv6.label;
1242                 ipv6_key->ipv6_proto = swkey->ip.proto;
1243                 ipv6_key->ipv6_tclass = swkey->ip.tos;
1244                 ipv6_key->ipv6_hlimit = swkey->ip.ttl;
1245                 ipv6_key->ipv6_frag = swkey->ip.frag;
1246         } else if (swkey->eth.type == htons(ETH_P_ARP) ||
1247                    swkey->eth.type == htons(ETH_P_RARP)) {
1248                 struct ovs_key_arp *arp_key;
1249
1250                 nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
1251                 if (!nla)
1252                         goto nla_put_failure;
1253                 arp_key = nla_data(nla);
1254                 memset(arp_key, 0, sizeof(struct ovs_key_arp));
1255                 arp_key->arp_sip = swkey->ipv4.addr.src;
1256                 arp_key->arp_tip = swkey->ipv4.addr.dst;
1257                 arp_key->arp_op = htons(swkey->ip.proto);
1258                 memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1259                 memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1260         }
1261
1262         if ((swkey->eth.type == htons(ETH_P_IP) ||
1263              swkey->eth.type == htons(ETH_P_IPV6)) &&
1264              swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1265
1266                 if (swkey->ip.proto == IPPROTO_TCP) {
1267                         struct ovs_key_tcp *tcp_key;
1268
1269                         nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
1270                         if (!nla)
1271                                 goto nla_put_failure;
1272                         tcp_key = nla_data(nla);
1273                         if (swkey->eth.type == htons(ETH_P_IP)) {
1274                                 tcp_key->tcp_src = swkey->ipv4.tp.src;
1275                                 tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1276                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1277                                 tcp_key->tcp_src = swkey->ipv6.tp.src;
1278                                 tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1279                         }
1280                 } else if (swkey->ip.proto == IPPROTO_UDP) {
1281                         struct ovs_key_udp *udp_key;
1282
1283                         nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
1284                         if (!nla)
1285                                 goto nla_put_failure;
1286                         udp_key = nla_data(nla);
1287                         if (swkey->eth.type == htons(ETH_P_IP)) {
1288                                 udp_key->udp_src = swkey->ipv4.tp.src;
1289                                 udp_key->udp_dst = swkey->ipv4.tp.dst;
1290                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1291                                 udp_key->udp_src = swkey->ipv6.tp.src;
1292                                 udp_key->udp_dst = swkey->ipv6.tp.dst;
1293                         }
1294                 } else if (swkey->eth.type == htons(ETH_P_IP) &&
1295                            swkey->ip.proto == IPPROTO_ICMP) {
1296                         struct ovs_key_icmp *icmp_key;
1297
1298                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
1299                         if (!nla)
1300                                 goto nla_put_failure;
1301                         icmp_key = nla_data(nla);
1302                         icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1303                         icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1304                 } else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1305                            swkey->ip.proto == IPPROTO_ICMPV6) {
1306                         struct ovs_key_icmpv6 *icmpv6_key;
1307
1308                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
1309                                                 sizeof(*icmpv6_key));
1310                         if (!nla)
1311                                 goto nla_put_failure;
1312                         icmpv6_key = nla_data(nla);
1313                         icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1314                         icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1315
1316                         if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1317                             icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1318                                 struct ovs_key_nd *nd_key;
1319
1320                                 nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
1321                                 if (!nla)
1322                                         goto nla_put_failure;
1323                                 nd_key = nla_data(nla);
1324                                 memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1325                                                         sizeof(nd_key->nd_target));
1326                                 memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1327                                 memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1328                         }
1329                 }
1330         }
1331
1332 unencap:
1333         if (encap)
1334                 nla_nest_end(skb, encap);
1335
1336         return 0;
1337
1338 nla_put_failure:
1339         return -EMSGSIZE;
1340 }
1341
1342 /* Initializes the flow module.
1343  * Returns zero if successful or a negative error code. */
1344 int ovs_flow_init(void)
1345 {
1346         flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1347                                         0, NULL);
1348         if (flow_cache == NULL)
1349                 return -ENOMEM;
1350
1351         return 0;
1352 }
1353
1354 /* Uninitializes the flow module. */
1355 void ovs_flow_exit(void)
1356 {
1357         kmem_cache_destroy(flow_cache);
1358 }