datapath/flow.c

   1 /*
   2  * Copyright (c) 2007-2011 Nicira Networks.
   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/if_ether.h>
  36 #include <linux/ip.h>
  37 #include <linux/ipv6.h>
  38 #include <linux/tcp.h>
  39 #include <linux/udp.h>
  40 #include <linux/icmp.h>
  41 #include <linux/icmpv6.h>
  42 #include <linux/rculist.h>
  43 #include <net/ip.h>
  44 #include <net/ipv6.h>
  45 #include <net/ndisc.h>
  46
  47 #include "vlan.h"
  48
  49 static struct kmem_cache *flow_cache;
  50 static unsigned int hash_seed __read_mostly;
  51
  52 static int check_header(struct sk_buff *skb, int len)
  53 {
  54         if (unlikely(skb->len < len))
  55                 return -EINVAL;
  56         if (unlikely(!pskb_may_pull(skb, len)))
  57                 return -ENOMEM;
  58         return 0;
  59 }
  60
  61 static bool arphdr_ok(struct sk_buff *skb)
  62 {
  63         return pskb_may_pull(skb, skb_network_offset(skb) +
  64                                   sizeof(struct arp_eth_header));
  65 }
  66
  67 static int check_iphdr(struct sk_buff *skb)
  68 {
  69         unsigned int nh_ofs = skb_network_offset(skb);
  70         unsigned int ip_len;
  71         int err;
  72
  73         err = check_header(skb, nh_ofs + sizeof(struct iphdr));
  74         if (unlikely(err))
  75                 return err;
  76
  77         ip_len = ip_hdrlen(skb);
  78         if (unlikely(ip_len < sizeof(struct iphdr) ||
  79                      skb->len < nh_ofs + ip_len))
  80                 return -EINVAL;
  81
  82         skb_set_transport_header(skb, nh_ofs + ip_len);
  83         return 0;
  84 }
  85
  86 static bool tcphdr_ok(struct sk_buff *skb)
  87 {
  88         int th_ofs = skb_transport_offset(skb);
  89         int tcp_len;
  90
  91         if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
  92                 return false;
  93
  94         tcp_len = tcp_hdrlen(skb);
  95         if (unlikely(tcp_len < sizeof(struct tcphdr) ||
  96                      skb->len < th_ofs + tcp_len))
  97                 return false;
  98
  99         return true;
 100 }
 101
 102 static bool udphdr_ok(struct sk_buff *skb)
 103 {
 104         return pskb_may_pull(skb, skb_transport_offset(skb) +
 105                                   sizeof(struct udphdr));
 106 }
 107
 108 static bool icmphdr_ok(struct sk_buff *skb)
 109 {
 110         return pskb_may_pull(skb, skb_transport_offset(skb) +
 111                                   sizeof(struct icmphdr));
 112 }
 113
 114 u64 ovs_flow_used_time(unsigned long flow_jiffies)
 115 {
 116         struct timespec cur_ts;
 117         u64 cur_ms, idle_ms;
 118
 119         ktime_get_ts(&cur_ts);
 120         idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
 121         cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
 122                  cur_ts.tv_nsec / NSEC_PER_MSEC;
 123
 124         return cur_ms - idle_ms;
 125 }
 126
 127 #define SW_FLOW_KEY_OFFSET(field)               \
 128         (offsetof(struct sw_flow_key, field) +  \
 129          FIELD_SIZEOF(struct sw_flow_key, field))
 130
 131 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key,
 132                          int *key_lenp)
 133 {
 134         unsigned int nh_ofs = skb_network_offset(skb);
 135         unsigned int nh_len;
 136         int payload_ofs;
 137         struct ipv6hdr *nh;
 138         uint8_t nexthdr;
 139         __be16 frag_off;
 140         int err;
 141
 142         *key_lenp = SW_FLOW_KEY_OFFSET(ipv6.label);
 143
 144         err = check_header(skb, nh_ofs + sizeof(*nh));
 145         if (unlikely(err))
 146                 return err;
 147
 148         nh = ipv6_hdr(skb);
 149         nexthdr = nh->nexthdr;
 150         payload_ofs = (u8 *)(nh + 1) - skb->data;
 151
 152         key->ip.proto = NEXTHDR_NONE;
 153         key->ip.tos = ipv6_get_dsfield(nh);
 154         key->ip.ttl = nh->hop_limit;
 155         key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 156         key->ipv6.addr.src = nh->saddr;
 157         key->ipv6.addr.dst = nh->daddr;
 158
 159         payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
 160         if (unlikely(payload_ofs < 0))
 161                 return -EINVAL;
 162
 163         if (frag_off) {
 164                 if (frag_off & htons(~0x7))
 165                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 166                 else
 167                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 168         }
 169
 170         nh_len = payload_ofs - nh_ofs;
 171         skb_set_transport_header(skb, nh_ofs + nh_len);
 172         key->ip.proto = nexthdr;
 173         return nh_len;
 174 }
 175
 176 static bool icmp6hdr_ok(struct sk_buff *skb)
 177 {
 178         return pskb_may_pull(skb, skb_transport_offset(skb) +
 179                                   sizeof(struct icmp6hdr));
 180 }
 181
 182 #define TCP_FLAGS_OFFSET 13
 183 #define TCP_FLAG_MASK 0x3f
 184
 185 void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb)
 186 {
 187         u8 tcp_flags = 0;
 188
 189         if (flow->key.eth.type == htons(ETH_P_IP) &&
 190             flow->key.ip.proto == IPPROTO_TCP) {
 191                 u8 *tcp = (u8 *)tcp_hdr(skb);
 192                 tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
 193         }
 194
 195         spin_lock(&flow->lock);
 196         flow->used = jiffies;
 197         flow->packet_count++;
 198         flow->byte_count += skb->len;
 199         flow->tcp_flags |= tcp_flags;
 200         spin_unlock(&flow->lock);
 201 }
 202
 203 struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *actions)
 204 {
 205         int actions_len = nla_len(actions);
 206         struct sw_flow_actions *sfa;
 207
 208         /* At least DP_MAX_PORTS actions are required to be able to flood a
 209          * packet to every port.  Factor of 2 allows for setting VLAN tags,
 210          * etc. */
 211         if (actions_len > 2 * DP_MAX_PORTS * nla_total_size(4))
 212                 return ERR_PTR(-EINVAL);
 213
 214         sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
 215         if (!sfa)
 216                 return ERR_PTR(-ENOMEM);
 217
 218         sfa->actions_len = actions_len;
 219         memcpy(sfa->actions, nla_data(actions), actions_len);
 220         return sfa;
 221 }
 222
 223 struct sw_flow *ovs_flow_alloc(void)
 224 {
 225         struct sw_flow *flow;
 226
 227         flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
 228         if (!flow)
 229                 return ERR_PTR(-ENOMEM);
 230
 231         spin_lock_init(&flow->lock);
 232         atomic_set(&flow->refcnt, 1);
 233         flow->sf_acts = NULL;
 234         flow->dead = false;
 235
 236         return flow;
 237 }
 238
 239 static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
 240 {
 241         return flex_array_get(table->buckets,
 242                                 (hash & (table->n_buckets - 1)));
 243 }
 244
 245 static struct flex_array *alloc_buckets(unsigned int n_buckets)
 246 {
 247         struct flex_array *buckets;
 248         int i, err;
 249
 250         buckets = flex_array_alloc(sizeof(struct hlist_head *),
 251                                    n_buckets, GFP_KERNEL);
 252         if (!buckets)
 253                 return NULL;
 254
 255         err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
 256         if (err) {
 257                 flex_array_free(buckets);
 258                 return NULL;
 259         }
 260
 261         for (i = 0; i < n_buckets; i++)
 262                 INIT_HLIST_HEAD((struct hlist_head *)
 263                                         flex_array_get(buckets, i));
 264
 265         return buckets;
 266 }
 267
 268 static void free_buckets(struct flex_array *buckets)
 269 {
 270         flex_array_free(buckets);
 271 }
 272
 273 struct flow_table *ovs_flow_tbl_alloc(int new_size)
 274 {
 275         struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
 276
 277         if (!table)
 278                 return NULL;
 279
 280         table->buckets = alloc_buckets(new_size);
 281
 282         if (!table->buckets) {
 283                 kfree(table);
 284                 return NULL;
 285         }
 286         table->n_buckets = new_size;
 287         table->count = 0;
 288
 289         return table;
 290 }
 291
 292 static void flow_free(struct sw_flow *flow)
 293 {
 294         flow->dead = true;
 295         ovs_flow_put(flow);
 296 }
 297
 298 void ovs_flow_tbl_destroy(struct flow_table *table)
 299 {
 300         int i;
 301
 302         if (!table)
 303                 return;
 304
 305         for (i = 0; i < table->n_buckets; i++) {
 306                 struct sw_flow *flow;
 307                 struct hlist_head *head = flex_array_get(table->buckets, i);
 308                 struct hlist_node *node, *n;
 309
 310                 hlist_for_each_entry_safe(flow, node, n, head, hash_node) {
 311                         hlist_del_init_rcu(&flow->hash_node);
 312                         flow_free(flow);
 313                 }
 314         }
 315
 316         free_buckets(table->buckets);
 317         kfree(table);
 318 }
 319
 320 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
 321 {
 322         struct flow_table *table = container_of(rcu, struct flow_table, rcu);
 323
 324         ovs_flow_tbl_destroy(table);
 325 }
 326
 327 void ovs_flow_tbl_deferred_destroy(struct flow_table *table)
 328 {
 329         if (!table)
 330                 return;
 331
 332         call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
 333 }
 334
 335 struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
 336 {
 337         struct sw_flow *flow;
 338         struct hlist_head *head;
 339         struct hlist_node *n;
 340         int i;
 341
 342         while (*bucket < table->n_buckets) {
 343                 i = 0;
 344                 head = flex_array_get(table->buckets, *bucket);
 345                 hlist_for_each_entry_rcu(flow, n, head, hash_node) {
 346                         if (i < *last) {
 347                                 i++;
 348                                 continue;
 349                         }
 350                         *last = i + 1;
 351                         return flow;
 352                 }
 353                 (*bucket)++;
 354                 *last = 0;
 355         }
 356
 357         return NULL;
 358 }
 359
 360 struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
 361 {
 362         struct flow_table *new_table;
 363         int n_buckets = table->n_buckets * 2;
 364         int i;
 365
 366         new_table = ovs_flow_tbl_alloc(n_buckets);
 367         if (!new_table)
 368                 return ERR_PTR(-ENOMEM);
 369
 370         for (i = 0; i < table->n_buckets; i++) {
 371                 struct sw_flow *flow;
 372                 struct hlist_head *head;
 373                 struct hlist_node *n, *pos;
 374
 375                 head = flex_array_get(table->buckets, i);
 376
 377                 hlist_for_each_entry_safe(flow, n, pos, head, hash_node) {
 378                         hlist_del_init_rcu(&flow->hash_node);
 379                         ovs_flow_tbl_insert(new_table, flow);
 380                 }
 381         }
 382
 383         return new_table;
 384 }
 385
 386 /* RCU callback used by ovs_flow_deferred_free. */
 387 static void rcu_free_flow_callback(struct rcu_head *rcu)
 388 {
 389         struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
 390
 391         flow->dead = true;
 392         ovs_flow_put(flow);
 393 }
 394
 395 /* Schedules 'flow' to be freed after the next RCU grace period.
 396  * The caller must hold rcu_read_lock for this to be sensible. */
 397 void ovs_flow_deferred_free(struct sw_flow *flow)
 398 {
 399         call_rcu(&flow->rcu, rcu_free_flow_callback);
 400 }
 401
 402 void ovs_flow_hold(struct sw_flow *flow)
 403 {
 404         atomic_inc(&flow->refcnt);
 405 }
 406
 407 void ovs_flow_put(struct sw_flow *flow)
 408 {
 409         if (unlikely(!flow))
 410                 return;
 411
 412         if (atomic_dec_and_test(&flow->refcnt)) {
 413                 kfree((struct sf_flow_acts __force *)flow->sf_acts);
 414                 kmem_cache_free(flow_cache, flow);
 415         }
 416 }
 417
 418 /* RCU callback used by ovs_flow_deferred_free_acts. */
 419 static void rcu_free_acts_callback(struct rcu_head *rcu)
 420 {
 421         struct sw_flow_actions *sf_acts = container_of(rcu,
 422                         struct sw_flow_actions, rcu);
 423         kfree(sf_acts);
 424 }
 425
 426 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
 427  * The caller must hold rcu_read_lock for this to be sensible. */
 428 void ovs_flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
 429 {
 430         call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
 431 }
 432
 433 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 434 {
 435         struct qtag_prefix {
 436                 __be16 eth_type; /* ETH_P_8021Q */
 437                 __be16 tci;
 438         };
 439         struct qtag_prefix *qp;
 440
 441         if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
 442                 return 0;
 443
 444         if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
 445                                          sizeof(__be16))))
 446                 return -ENOMEM;
 447
 448         qp = (struct qtag_prefix *) skb->data;
 449         key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
 450         __skb_pull(skb, sizeof(struct qtag_prefix));
 451
 452         return 0;
 453 }
 454
 455 static __be16 parse_ethertype(struct sk_buff *skb)
 456 {
 457         struct llc_snap_hdr {
 458                 u8  dsap;  /* Always 0xAA */
 459                 u8  ssap;  /* Always 0xAA */
 460                 u8  ctrl;
 461                 u8  oui[3];
 462                 __be16 ethertype;
 463         };
 464         struct llc_snap_hdr *llc;
 465         __be16 proto;
 466
 467         proto = *(__be16 *) skb->data;
 468         __skb_pull(skb, sizeof(__be16));
 469
 470         if (ntohs(proto) >= 1536)
 471                 return proto;
 472
 473         if (skb->len < sizeof(struct llc_snap_hdr))
 474                 return htons(ETH_P_802_2);
 475
 476         if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
 477                 return htons(0);
 478
 479         llc = (struct llc_snap_hdr *) skb->data;
 480         if (llc->dsap != LLC_SAP_SNAP ||
 481             llc->ssap != LLC_SAP_SNAP ||
 482             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
 483                 return htons(ETH_P_802_2);
 484
 485         __skb_pull(skb, sizeof(struct llc_snap_hdr));
 486         return llc->ethertype;
 487 }
 488
 489 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
 490                         int *key_lenp, int nh_len)
 491 {
 492         struct icmp6hdr *icmp = icmp6_hdr(skb);
 493         int error = 0;
 494         int key_len;
 495
 496         /* The ICMPv6 type and code fields use the 16-bit transport port
 497          * fields, so we need to store them in 16-bit network byte order.
 498          */
 499         key->ipv6.tp.src = htons(icmp->icmp6_type);
 500         key->ipv6.tp.dst = htons(icmp->icmp6_code);
 501         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 502
 503         if (icmp->icmp6_code == 0 &&
 504             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
 505              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 506                 int icmp_len = skb->len - skb_transport_offset(skb);
 507                 struct nd_msg *nd;
 508                 int offset;
 509
 510                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 511
 512                 /* In order to process neighbor discovery options, we need the
 513                  * entire packet.
 514                  */
 515                 if (unlikely(icmp_len < sizeof(*nd)))
 516                         goto out;
 517                 if (unlikely(skb_linearize(skb))) {
 518                         error = -ENOMEM;
 519                         goto out;
 520                 }
 521
 522                 nd = (struct nd_msg *)skb_transport_header(skb);
 523                 key->ipv6.nd.target = nd->target;
 524                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 525
 526                 icmp_len -= sizeof(*nd);
 527                 offset = 0;
 528                 while (icmp_len >= 8) {
 529                         struct nd_opt_hdr *nd_opt =
 530                                  (struct nd_opt_hdr *)(nd->opt + offset);
 531                         int opt_len = nd_opt->nd_opt_len * 8;
 532
 533                         if (unlikely(!opt_len || opt_len > icmp_len))
 534                                 goto invalid;
 535
 536                         /* Store the link layer address if the appropriate
 537                          * option is provided.  It is considered an error if
 538                          * the same link layer option is specified twice.
 539                          */
 540                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
 541                             && opt_len == 8) {
 542                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
 543                                         goto invalid;
 544                                 memcpy(key->ipv6.nd.sll,
 545                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 546                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
 547                                    && opt_len == 8) {
 548                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
 549                                         goto invalid;
 550                                 memcpy(key->ipv6.nd.tll,
 551                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 552                         }
 553
 554                         icmp_len -= opt_len;
 555                         offset += opt_len;
 556                 }
 557         }
 558
 559         goto out;
 560
 561 invalid:
 562         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
 563         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
 564         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
 565
 566 out:
 567         *key_lenp = key_len;
 568         return error;
 569 }
 570
 571 /**
 572  * ovs_flow_extract - extracts a flow key from an Ethernet frame.
 573  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 574  * Ethernet header
 575  * @in_port: port number on which @skb was received.
 576  * @key: output flow key
 577  * @key_lenp: length of output flow key
 578  *
 579  * The caller must ensure that skb->len >= ETH_HLEN.
 580  *
 581  * Returns 0 if successful, otherwise a negative errno value.
 582  *
 583  * Initializes @skb header pointers as follows:
 584  *
 585  *    - skb->mac_header: the Ethernet header.
 586  *
 587  *    - skb->network_header: just past the Ethernet header, or just past the
 588  *      VLAN header, to the first byte of the Ethernet payload.
 589  *
 590  *    - skb->transport_header: If key->dl_type is ETH_P_IP or ETH_P_IPV6
 591  *      on output, then just past the IP header, if one is present and
 592  *      of a correct length, otherwise the same as skb->network_header.
 593  *      For other key->dl_type values it is left untouched.
 594  */
 595 int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
 596                  int *key_lenp)
 597 {
 598         int error = 0;
 599         int key_len = SW_FLOW_KEY_OFFSET(eth);
 600         struct ethhdr *eth;
 601
 602         memset(key, 0, sizeof(*key));
 603
 604         key->phy.priority = skb->priority;
 605         key->phy.tun_id = OVS_CB(skb)->tun_id;
 606         key->phy.in_port = in_port;
 607
 608         skb_reset_mac_header(skb);
 609
 610         /* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
 611          * header in the linear data area.
 612          */
 613         eth = eth_hdr(skb);
 614         memcpy(key->eth.src, eth->h_source, ETH_ALEN);
 615         memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
 616
 617         __skb_pull(skb, 2 * ETH_ALEN);
 618
 619         if (vlan_tx_tag_present(skb))
 620                 key->eth.tci = htons(vlan_get_tci(skb));
 621         else if (eth->h_proto == htons(ETH_P_8021Q))
 622                 if (unlikely(parse_vlan(skb, key)))
 623                         return -ENOMEM;
 624
 625         key->eth.type = parse_ethertype(skb);
 626         if (unlikely(key->eth.type == htons(0)))
 627                 return -ENOMEM;
 628
 629         skb_reset_network_header(skb);
 630         __skb_push(skb, skb->data - skb_mac_header(skb));
 631
 632         /* Network layer. */
 633         if (key->eth.type == htons(ETH_P_IP)) {
 634                 struct iphdr *nh;
 635                 __be16 offset;
 636
 637                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
 638
 639                 error = check_iphdr(skb);
 640                 if (unlikely(error)) {
 641                         if (error == -EINVAL) {
 642                                 skb->transport_header = skb->network_header;
 643                                 error = 0;
 644                         }
 645                         goto out;
 646                 }
 647
 648                 nh = ip_hdr(skb);
 649                 key->ipv4.addr.src = nh->saddr;
 650                 key->ipv4.addr.dst = nh->daddr;
 651
 652                 key->ip.proto = nh->protocol;
 653                 key->ip.tos = nh->tos;
 654                 key->ip.ttl = nh->ttl;
 655
 656                 offset = nh->frag_off & htons(IP_OFFSET);
 657                 if (offset) {
 658                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 659                         goto out;
 660                 }
 661                 if (nh->frag_off & htons(IP_MF) ||
 662                          skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 663                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 664
 665                 /* Transport layer. */
 666                 if (key->ip.proto == IPPROTO_TCP) {
 667                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 668                         if (tcphdr_ok(skb)) {
 669                                 struct tcphdr *tcp = tcp_hdr(skb);
 670                                 key->ipv4.tp.src = tcp->source;
 671                                 key->ipv4.tp.dst = tcp->dest;
 672                         }
 673                 } else if (key->ip.proto == IPPROTO_UDP) {
 674                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 675                         if (udphdr_ok(skb)) {
 676                                 struct udphdr *udp = udp_hdr(skb);
 677                                 key->ipv4.tp.src = udp->source;
 678                                 key->ipv4.tp.dst = udp->dest;
 679                         }
 680                 } else if (key->ip.proto == IPPROTO_ICMP) {
 681                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 682                         if (icmphdr_ok(skb)) {
 683                                 struct icmphdr *icmp = icmp_hdr(skb);
 684                                 /* The ICMP type and code fields use the 16-bit
 685                                  * transport port fields, so we need to store
 686                                  * them in 16-bit network byte order. */
 687                                 key->ipv4.tp.src = htons(icmp->type);
 688                                 key->ipv4.tp.dst = htons(icmp->code);
 689                         }
 690                 }
 691
 692         } else if (key->eth.type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
 693                 struct arp_eth_header *arp;
 694
 695                 arp = (struct arp_eth_header *)skb_network_header(skb);
 696
 697                 if (arp->ar_hrd == htons(ARPHRD_ETHER)
 698                                 && arp->ar_pro == htons(ETH_P_IP)
 699                                 && arp->ar_hln == ETH_ALEN
 700                                 && arp->ar_pln == 4) {
 701
 702                         /* We only match on the lower 8 bits of the opcode. */
 703                         if (ntohs(arp->ar_op) <= 0xff)
 704                                 key->ip.proto = ntohs(arp->ar_op);
 705
 706                         if (key->ip.proto == ARPOP_REQUEST
 707                                         || key->ip.proto == ARPOP_REPLY) {
 708                                 memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
 709                                 memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
 710                                 memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
 711                                 memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
 712                                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
 713                         }
 714                 }
 715         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 716                 int nh_len;             /* IPv6 Header + Extensions */
 717
 718                 nh_len = parse_ipv6hdr(skb, key, &key_len);
 719                 if (unlikely(nh_len < 0)) {
 720                         if (nh_len == -EINVAL)
 721                                 skb->transport_header = skb->network_header;
 722                         else
 723                                 error = nh_len;
 724                         goto out;
 725                 }
 726
 727                 if (key->ip.frag == OVS_FRAG_TYPE_LATER)
 728                         goto out;
 729                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 730                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 731
 732                 /* Transport layer. */
 733                 if (key->ip.proto == NEXTHDR_TCP) {
 734                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 735                         if (tcphdr_ok(skb)) {
 736                                 struct tcphdr *tcp = tcp_hdr(skb);
 737                                 key->ipv6.tp.src = tcp->source;
 738                                 key->ipv6.tp.dst = tcp->dest;
 739                         }
 740                 } else if (key->ip.proto == NEXTHDR_UDP) {
 741                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 742                         if (udphdr_ok(skb)) {
 743                                 struct udphdr *udp = udp_hdr(skb);
 744                                 key->ipv6.tp.src = udp->source;
 745                                 key->ipv6.tp.dst = udp->dest;
 746                         }
 747                 } else if (key->ip.proto == NEXTHDR_ICMP) {
 748                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 749                         if (icmp6hdr_ok(skb)) {
 750                                 error = parse_icmpv6(skb, key, &key_len, nh_len);
 751                                 if (error < 0)
 752                                         goto out;
 753                         }
 754                 }
 755         }
 756
 757 out:
 758         *key_lenp = key_len;
 759         return error;
 760 }
 761
 762 u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len)
 763 {
 764         return jhash2((u32 *)key, DIV_ROUND_UP(key_len, sizeof(u32)), hash_seed);
 765 }
 766
 767 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
 768                                 struct sw_flow_key *key, int key_len)
 769 {
 770         struct sw_flow *flow;
 771         struct hlist_node *n;
 772         struct hlist_head *head;
 773         u32 hash;
 774
 775         hash = ovs_flow_hash(key, key_len);
 776
 777         head = find_bucket(table, hash);
 778         hlist_for_each_entry_rcu(flow, n, head, hash_node) {
 779
 780                 if (flow->hash == hash &&
 781                     !memcmp(&flow->key, key, key_len)) {
 782                         return flow;
 783                 }
 784         }
 785         return NULL;
 786 }
 787
 788 void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
 789 {
 790         struct hlist_head *head;
 791
 792         head = find_bucket(table, flow->hash);
 793         hlist_add_head_rcu(&flow->hash_node, head);
 794         table->count++;
 795 }
 796
 797 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
 798 {
 799         if (!hlist_unhashed(&flow->hash_node)) {
 800                 hlist_del_init_rcu(&flow->hash_node);
 801                 table->count--;
 802                 BUG_ON(table->count < 0);
 803         }
 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_ETHERNET] = sizeof(struct ovs_key_ethernet),
 812         [OVS_KEY_ATTR_VLAN] = sizeof(__be16),
 813         [OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
 814         [OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
 815         [OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
 816         [OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
 817         [OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
 818         [OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
 819         [OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
 820         [OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
 821         [OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
 822
 823         /* Not upstream. */
 824         [OVS_KEY_ATTR_TUN_ID] = sizeof(__be64),
 825 };
 826
 827 static int ipv4_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 828                                   const struct nlattr *a[], u64 *attrs)
 829 {
 830         const struct ovs_key_icmp *icmp_key;
 831         const struct ovs_key_tcp *tcp_key;
 832         const struct ovs_key_udp *udp_key;
 833
 834         switch (swkey->ip.proto) {
 835         case IPPROTO_TCP:
 836                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 837                         return -EINVAL;
 838                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 839
 840                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 841                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 842                 swkey->ipv4.tp.src = tcp_key->tcp_src;
 843                 swkey->ipv4.tp.dst = tcp_key->tcp_dst;
 844                 break;
 845
 846         case IPPROTO_UDP:
 847                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 848                         return -EINVAL;
 849                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 850
 851                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 852                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 853                 swkey->ipv4.tp.src = udp_key->udp_src;
 854                 swkey->ipv4.tp.dst = udp_key->udp_dst;
 855                 break;
 856
 857         case IPPROTO_ICMP:
 858                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMP)))
 859                         return -EINVAL;
 860                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
 861
 862                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 863                 icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
 864                 swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
 865                 swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
 866                 break;
 867         }
 868
 869         return 0;
 870 }
 871
 872 static int ipv6_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 873                                   const struct nlattr *a[], u64 *attrs)
 874 {
 875         const struct ovs_key_icmpv6 *icmpv6_key;
 876         const struct ovs_key_tcp *tcp_key;
 877         const struct ovs_key_udp *udp_key;
 878
 879         switch (swkey->ip.proto) {
 880         case IPPROTO_TCP:
 881                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 882                         return -EINVAL;
 883                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 884
 885                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 886                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 887                 swkey->ipv6.tp.src = tcp_key->tcp_src;
 888                 swkey->ipv6.tp.dst = tcp_key->tcp_dst;
 889                 break;
 890
 891         case IPPROTO_UDP:
 892                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 893                         return -EINVAL;
 894                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 895
 896                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 897                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 898                 swkey->ipv6.tp.src = udp_key->udp_src;
 899                 swkey->ipv6.tp.dst = udp_key->udp_dst;
 900                 break;
 901
 902         case IPPROTO_ICMPV6:
 903                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMPV6)))
 904                         return -EINVAL;
 905                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
 906
 907                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 908                 icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
 909                 swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
 910                 swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
 911
 912                 if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
 913                     swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 914                         const struct ovs_key_nd *nd_key;
 915
 916                         if (!(*attrs & (1 << OVS_KEY_ATTR_ND)))
 917                                 return -EINVAL;
 918                         *attrs &= ~(1 << OVS_KEY_ATTR_ND);
 919
 920                         *key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 921                         nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
 922                         memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
 923                                sizeof(swkey->ipv6.nd.target));
 924                         memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
 925                         memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
 926                 }
 927                 break;
 928         }
 929
 930         return 0;
 931 }
 932
 933 static int parse_flow_nlattrs(const struct nlattr *attr,
 934                               const struct nlattr *a[], u64 *attrsp)
 935 {
 936         const struct nlattr *nla;
 937         u64 attrs;
 938         int rem;
 939
 940         attrs = 0;
 941         nla_for_each_nested(nla, attr, rem) {
 942                 u16 type = nla_type(nla);
 943                 int expected_len;
 944
 945                 if (type > OVS_KEY_ATTR_MAX || attrs & (1ULL << type))
 946                         return -EINVAL;
 947
 948                 expected_len = ovs_key_lens[type];
 949                 if (nla_len(nla) != expected_len && expected_len != -1)
 950                         return -EINVAL;
 951
 952                 attrs |= 1ULL << type;
 953                 a[type] = nla;
 954         }
 955         if (rem)
 956                 return -EINVAL;
 957
 958         *attrsp = attrs;
 959         return 0;
 960 }
 961
 962 /**
 963  * ovs_flow_from_nlattrs - parses Netlink attributes into a flow key.
 964  * @swkey: receives the extracted flow key.
 965  * @key_lenp: number of bytes used in @swkey.
 966  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
 967  * sequence.
 968  */
 969 int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
 970                       const struct nlattr *attr)
 971 {
 972         const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
 973         const struct ovs_key_ethernet *eth_key;
 974         int key_len;
 975         u64 attrs;
 976         int err;
 977
 978         memset(swkey, 0, sizeof(struct sw_flow_key));
 979         key_len = SW_FLOW_KEY_OFFSET(eth);
 980
 981         err = parse_flow_nlattrs(attr, a, &attrs);
 982         if (err)
 983                 return err;
 984
 985         /* Metadata attributes. */
 986         if (attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
 987                 swkey->phy.priority = nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]);
 988                 attrs &= ~(1 << OVS_KEY_ATTR_PRIORITY);
 989         }
 990         if (attrs & (1 << OVS_KEY_ATTR_IN_PORT)) {
 991                 u32 in_port = nla_get_u32(a[OVS_KEY_ATTR_IN_PORT]);
 992                 if (in_port >= DP_MAX_PORTS)
 993                         return -EINVAL;
 994                 swkey->phy.in_port = in_port;
 995                 attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
 996         } else {
 997                 swkey->phy.in_port = USHRT_MAX;
 998         }
 999
1000         if (attrs & (1ULL << OVS_KEY_ATTR_TUN_ID)) {
1001                 swkey->phy.tun_id = nla_get_be64(a[OVS_KEY_ATTR_TUN_ID]);
1002                 attrs &= ~(1ULL << OVS_KEY_ATTR_TUN_ID);
1003         }
1004
1005         /* Data attributes. */
1006         if (!(attrs & (1 << OVS_KEY_ATTR_ETHERNET)))
1007                 return -EINVAL;
1008         attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
1009
1010         eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
1011         memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
1012         memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
1013
1014         if (attrs & (1u << OVS_KEY_ATTR_ETHERTYPE) &&
1015             nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q)) {
1016                 const struct nlattr *encap;
1017                 __be16 tci;
1018
1019                 if (attrs != ((1 << OVS_KEY_ATTR_VLAN) |
1020                               (1 << OVS_KEY_ATTR_ETHERTYPE) |
1021                               (1 << OVS_KEY_ATTR_ENCAP)))
1022                         return -EINVAL;
1023
1024                 encap = a[OVS_KEY_ATTR_ENCAP];
1025                 tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
1026                 if (tci & htons(VLAN_TAG_PRESENT)) {
1027                         swkey->eth.tci = tci;
1028
1029                         err = parse_flow_nlattrs(encap, a, &attrs);
1030                         if (err)
1031                                 return err;
1032                 } else if (!tci) {
1033                         /* Corner case for truncated 802.1Q header. */
1034                         if (nla_len(encap))
1035                                 return -EINVAL;
1036
1037                         swkey->eth.type = htons(ETH_P_8021Q);
1038                         *key_lenp = key_len;
1039                         return 0;
1040                 } else {
1041                         return -EINVAL;
1042                 }
1043         }
1044
1045         if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
1046                 swkey->eth.type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
1047                 if (ntohs(swkey->eth.type) < 1536)
1048                         return -EINVAL;
1049                 attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
1050         } else {
1051                 swkey->eth.type = htons(ETH_P_802_2);
1052         }
1053
1054         if (swkey->eth.type == htons(ETH_P_IP)) {
1055                 const struct ovs_key_ipv4 *ipv4_key;
1056
1057                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV4)))
1058                         return -EINVAL;
1059                 attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
1060
1061                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
1062                 ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
1063                 if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
1064                         return -EINVAL;
1065                 swkey->ip.proto = ipv4_key->ipv4_proto;
1066                 swkey->ip.tos = ipv4_key->ipv4_tos;
1067                 swkey->ip.ttl = ipv4_key->ipv4_ttl;
1068                 swkey->ip.frag = ipv4_key->ipv4_frag;
1069                 swkey->ipv4.addr.src = ipv4_key->ipv4_src;
1070                 swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
1071
1072                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1073                         err = ipv4_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1074                         if (err)
1075                                 return err;
1076                 }
1077         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1078                 const struct ovs_key_ipv6 *ipv6_key;
1079
1080                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV6)))
1081                         return -EINVAL;
1082                 attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
1083
1084                 key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
1085                 ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
1086                 if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
1087                         return -EINVAL;
1088                 swkey->ipv6.label = ipv6_key->ipv6_label;
1089                 swkey->ip.proto = ipv6_key->ipv6_proto;
1090                 swkey->ip.tos = ipv6_key->ipv6_tclass;
1091                 swkey->ip.ttl = ipv6_key->ipv6_hlimit;
1092                 swkey->ip.frag = ipv6_key->ipv6_frag;
1093                 memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
1094                        sizeof(swkey->ipv6.addr.src));
1095                 memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
1096                        sizeof(swkey->ipv6.addr.dst));
1097
1098                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1099                         err = ipv6_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1100                         if (err)
1101                                 return err;
1102                 }
1103         } else if (swkey->eth.type == htons(ETH_P_ARP)) {
1104                 const struct ovs_key_arp *arp_key;
1105
1106                 if (!(attrs & (1 << OVS_KEY_ATTR_ARP)))
1107                         return -EINVAL;
1108                 attrs &= ~(1 << OVS_KEY_ATTR_ARP);
1109
1110                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
1111                 arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
1112                 swkey->ipv4.addr.src = arp_key->arp_sip;
1113                 swkey->ipv4.addr.dst = arp_key->arp_tip;
1114                 if (arp_key->arp_op & htons(0xff00))
1115                         return -EINVAL;
1116                 swkey->ip.proto = ntohs(arp_key->arp_op);
1117                 memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
1118                 memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
1119         }
1120
1121         if (attrs)
1122                 return -EINVAL;
1123         *key_lenp = key_len;
1124
1125         return 0;
1126 }
1127
1128 /**
1129  * ovs_flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
1130  * @in_port: receives the extracted input port.
1131  * @tun_id: receives the extracted tunnel ID.
1132  * @key: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1133  * sequence.
1134  *
1135  * This parses a series of Netlink attributes that form a flow key, which must
1136  * take the same form accepted by flow_from_nlattrs(), but only enough of it to
1137  * get the metadata, that is, the parts of the flow key that cannot be
1138  * extracted from the packet itself.
1139  */
1140 int ovs_flow_metadata_from_nlattrs(u32 *priority, u16 *in_port, __be64 *tun_id,
1141                                    const struct nlattr *attr)
1142 {
1143         const struct nlattr *nla;
1144         int rem;
1145
1146         *in_port = USHRT_MAX;
1147         *tun_id = 0;
1148         *priority = 0;
1149
1150         nla_for_each_nested(nla, attr, rem) {
1151                 int type = nla_type(nla);
1152
1153                 if (type <= OVS_KEY_ATTR_MAX && ovs_key_lens[type] > 0) {
1154                         if (nla_len(nla) != ovs_key_lens[type])
1155                                 return -EINVAL;
1156
1157                         switch (type) {
1158                         case OVS_KEY_ATTR_PRIORITY:
1159                                 *priority = nla_get_u32(nla);
1160                                 break;
1161
1162                         case OVS_KEY_ATTR_TUN_ID:
1163                                 *tun_id = nla_get_be64(nla);
1164                                 break;
1165
1166                         case OVS_KEY_ATTR_IN_PORT:
1167                                 if (nla_get_u32(nla) >= DP_MAX_PORTS)
1168                                         return -EINVAL;
1169                                 *in_port = nla_get_u32(nla);
1170                                 break;
1171                         }
1172                 }
1173         }
1174         if (rem)
1175                 return -EINVAL;
1176         return 0;
1177 }
1178
1179 int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
1180 {
1181         struct ovs_key_ethernet *eth_key;
1182         struct nlattr *nla, *encap;
1183
1184         if (swkey->phy.priority)
1185                 NLA_PUT_U32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority);
1186
1187         if (swkey->phy.tun_id != cpu_to_be64(0))
1188                 NLA_PUT_BE64(skb, OVS_KEY_ATTR_TUN_ID, swkey->phy.tun_id);
1189
1190         if (swkey->phy.in_port != USHRT_MAX)
1191                 NLA_PUT_U32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port);
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                 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                 encap = nla_nest_start(skb, OVS_KEY_ATTR_ENCAP);
1204                 if (!swkey->eth.tci)
1205                         goto unencap;
1206         } else {
1207                 encap = NULL;
1208         }
1209
1210         if (swkey->eth.type == htons(ETH_P_802_2))
1211                 goto unencap;
1212
1213         NLA_PUT_BE16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type);
1214
1215         if (swkey->eth.type == htons(ETH_P_IP)) {
1216                 struct ovs_key_ipv4 *ipv4_key;
1217
1218                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
1219                 if (!nla)
1220                         goto nla_put_failure;
1221                 ipv4_key = nla_data(nla);
1222                 ipv4_key->ipv4_src = swkey->ipv4.addr.src;
1223                 ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
1224                 ipv4_key->ipv4_proto = swkey->ip.proto;
1225                 ipv4_key->ipv4_tos = swkey->ip.tos;
1226                 ipv4_key->ipv4_ttl = swkey->ip.ttl;
1227                 ipv4_key->ipv4_frag = swkey->ip.frag;
1228         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1229                 struct ovs_key_ipv6 *ipv6_key;
1230
1231                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
1232                 if (!nla)
1233                         goto nla_put_failure;
1234                 ipv6_key = nla_data(nla);
1235                 memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
1236                                 sizeof(ipv6_key->ipv6_src));
1237                 memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
1238                                 sizeof(ipv6_key->ipv6_dst));
1239                 ipv6_key->ipv6_label = swkey->ipv6.label;
1240                 ipv6_key->ipv6_proto = swkey->ip.proto;
1241                 ipv6_key->ipv6_tclass = swkey->ip.tos;
1242                 ipv6_key->ipv6_hlimit = swkey->ip.ttl;
1243                 ipv6_key->ipv6_frag = swkey->ip.frag;
1244         } else if (swkey->eth.type == htons(ETH_P_ARP)) {
1245                 struct ovs_key_arp *arp_key;
1246
1247                 nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
1248                 if (!nla)
1249                         goto nla_put_failure;
1250                 arp_key = nla_data(nla);
1251                 memset(arp_key, 0, sizeof(struct ovs_key_arp));
1252                 arp_key->arp_sip = swkey->ipv4.addr.src;
1253                 arp_key->arp_tip = swkey->ipv4.addr.dst;
1254                 arp_key->arp_op = htons(swkey->ip.proto);
1255                 memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1256                 memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1257         }
1258
1259         if ((swkey->eth.type == htons(ETH_P_IP) ||
1260              swkey->eth.type == htons(ETH_P_IPV6)) &&
1261              swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1262
1263                 if (swkey->ip.proto == IPPROTO_TCP) {
1264                         struct ovs_key_tcp *tcp_key;
1265
1266                         nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
1267                         if (!nla)
1268                                 goto nla_put_failure;
1269                         tcp_key = nla_data(nla);
1270                         if (swkey->eth.type == htons(ETH_P_IP)) {
1271                                 tcp_key->tcp_src = swkey->ipv4.tp.src;
1272                                 tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1273                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1274                                 tcp_key->tcp_src = swkey->ipv6.tp.src;
1275                                 tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1276                         }
1277                 } else if (swkey->ip.proto == IPPROTO_UDP) {
1278                         struct ovs_key_udp *udp_key;
1279
1280                         nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
1281                         if (!nla)
1282                                 goto nla_put_failure;
1283                         udp_key = nla_data(nla);
1284                         if (swkey->eth.type == htons(ETH_P_IP)) {
1285                                 udp_key->udp_src = swkey->ipv4.tp.src;
1286                                 udp_key->udp_dst = swkey->ipv4.tp.dst;
1287                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1288                                 udp_key->udp_src = swkey->ipv6.tp.src;
1289                                 udp_key->udp_dst = swkey->ipv6.tp.dst;
1290                         }
1291                 } else if (swkey->eth.type == htons(ETH_P_IP) &&
1292                            swkey->ip.proto == IPPROTO_ICMP) {
1293                         struct ovs_key_icmp *icmp_key;
1294
1295                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
1296                         if (!nla)
1297                                 goto nla_put_failure;
1298                         icmp_key = nla_data(nla);
1299                         icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1300                         icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1301                 } else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1302                            swkey->ip.proto == IPPROTO_ICMPV6) {
1303                         struct ovs_key_icmpv6 *icmpv6_key;
1304
1305                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
1306                                                 sizeof(*icmpv6_key));
1307                         if (!nla)
1308                                 goto nla_put_failure;
1309                         icmpv6_key = nla_data(nla);
1310                         icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1311                         icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1312
1313                         if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1314                             icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1315                                 struct ovs_key_nd *nd_key;
1316
1317                                 nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
1318                                 if (!nla)
1319                                         goto nla_put_failure;
1320                                 nd_key = nla_data(nla);
1321                                 memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1322                                                         sizeof(nd_key->nd_target));
1323                                 memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1324                                 memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1325                         }
1326                 }
1327         }
1328
1329 unencap:
1330         if (encap)
1331                 nla_nest_end(skb, encap);
1332
1333         return 0;
1334
1335 nla_put_failure:
1336         return -EMSGSIZE;
1337 }
1338
1339 /* Initializes the flow module.
1340  * Returns zero if successful or a negative error code. */
1341 int ovs_flow_init(void)
1342 {
1343         flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1344                                         0, NULL);
1345         if (flow_cache == NULL)
1346                 return -ENOMEM;
1347
1348         get_random_bytes(&hash_seed, sizeof(hash_seed));
1349
1350         return 0;
1351 }
1352
1353 /* Uninitializes the flow module. */
1354 void ovs_flow_exit(void)
1355 {
1356         kmem_cache_destroy(flow_cache);
1357 }