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/ip_tunnels.h>
  44 #include <net/ipv6.h>
  45 #include <net/ndisc.h>
  46
  47 static struct kmem_cache *flow_cache;
  48
  49 static int check_header(struct sk_buff *skb, int len)
  50 {
  51         if (unlikely(skb->len < len))
  52                 return -EINVAL;
  53         if (unlikely(!pskb_may_pull(skb, len)))
  54                 return -ENOMEM;
  55         return 0;
  56 }
  57
  58 static bool arphdr_ok(struct sk_buff *skb)
  59 {
  60         return pskb_may_pull(skb, skb_network_offset(skb) +
  61                                   sizeof(struct arp_eth_header));
  62 }
  63
  64 static int check_iphdr(struct sk_buff *skb)
  65 {
  66         unsigned int nh_ofs = skb_network_offset(skb);
  67         unsigned int ip_len;
  68         int err;
  69
  70         err = check_header(skb, nh_ofs + sizeof(struct iphdr));
  71         if (unlikely(err))
  72                 return err;
  73
  74         ip_len = ip_hdrlen(skb);
  75         if (unlikely(ip_len < sizeof(struct iphdr) ||
  76                      skb->len < nh_ofs + ip_len))
  77                 return -EINVAL;
  78
  79         skb_set_transport_header(skb, nh_ofs + ip_len);
  80         return 0;
  81 }
  82
  83 static bool tcphdr_ok(struct sk_buff *skb)
  84 {
  85         int th_ofs = skb_transport_offset(skb);
  86         int tcp_len;
  87
  88         if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
  89                 return false;
  90
  91         tcp_len = tcp_hdrlen(skb);
  92         if (unlikely(tcp_len < sizeof(struct tcphdr) ||
  93                      skb->len < th_ofs + tcp_len))
  94                 return false;
  95
  96         return true;
  97 }
  98
  99 static bool udphdr_ok(struct sk_buff *skb)
 100 {
 101         return pskb_may_pull(skb, skb_transport_offset(skb) +
 102                                   sizeof(struct udphdr));
 103 }
 104
 105 static bool icmphdr_ok(struct sk_buff *skb)
 106 {
 107         return pskb_may_pull(skb, skb_transport_offset(skb) +
 108                                   sizeof(struct icmphdr));
 109 }
 110
 111 u64 ovs_flow_used_time(unsigned long flow_jiffies)
 112 {
 113         struct timespec cur_ts;
 114         u64 cur_ms, idle_ms;
 115
 116         ktime_get_ts(&cur_ts);
 117         idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
 118         cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
 119                  cur_ts.tv_nsec / NSEC_PER_MSEC;
 120
 121         return cur_ms - idle_ms;
 122 }
 123
 124 #define SW_FLOW_KEY_OFFSET(field)               \
 125         (offsetof(struct sw_flow_key, field) +  \
 126          FIELD_SIZEOF(struct sw_flow_key, field))
 127
 128 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key,
 129                          int *key_lenp)
 130 {
 131         unsigned int nh_ofs = skb_network_offset(skb);
 132         unsigned int nh_len;
 133         int payload_ofs;
 134         struct ipv6hdr *nh;
 135         uint8_t nexthdr;
 136         __be16 frag_off;
 137         int err;
 138
 139         *key_lenp = SW_FLOW_KEY_OFFSET(ipv6.label);
 140
 141         err = check_header(skb, nh_ofs + sizeof(*nh));
 142         if (unlikely(err))
 143                 return err;
 144
 145         nh = ipv6_hdr(skb);
 146         nexthdr = nh->nexthdr;
 147         payload_ofs = (u8 *)(nh + 1) - skb->data;
 148
 149         key->ip.proto = NEXTHDR_NONE;
 150         key->ip.tos = ipv6_get_dsfield(nh);
 151         key->ip.ttl = nh->hop_limit;
 152         key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 153         key->ipv6.addr.src = nh->saddr;
 154         key->ipv6.addr.dst = nh->daddr;
 155
 156         payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
 157         if (unlikely(payload_ofs < 0))
 158                 return -EINVAL;
 159
 160         if (frag_off) {
 161                 if (frag_off & htons(~0x7))
 162                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 163                 else
 164                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 165         }
 166
 167         nh_len = payload_ofs - nh_ofs;
 168         skb_set_transport_header(skb, nh_ofs + nh_len);
 169         key->ip.proto = nexthdr;
 170         return nh_len;
 171 }
 172
 173 static bool icmp6hdr_ok(struct sk_buff *skb)
 174 {
 175         return pskb_may_pull(skb, skb_transport_offset(skb) +
 176                                   sizeof(struct icmp6hdr));
 177 }
 178
 179 #define TCP_FLAGS_OFFSET 13
 180 #define TCP_FLAG_MASK 0x3f
 181
 182 void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb)
 183 {
 184         u8 tcp_flags = 0;
 185
 186         if ((flow->key.eth.type == htons(ETH_P_IP) ||
 187              flow->key.eth.type == htons(ETH_P_IPV6)) &&
 188             flow->key.ip.proto == IPPROTO_TCP &&
 189             likely(skb->len >= skb_transport_offset(skb) + sizeof(struct tcphdr))) {
 190                 u8 *tcp = (u8 *)tcp_hdr(skb);
 191                 tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
 192         }
 193
 194         spin_lock(&flow->lock);
 195         flow->used = jiffies;
 196         flow->packet_count++;
 197         flow->byte_count += skb->len;
 198         flow->tcp_flags |= tcp_flags;
 199         spin_unlock(&flow->lock);
 200 }
 201
 202 struct sw_flow_actions *ovs_flow_actions_alloc(int size)
 203 {
 204         struct sw_flow_actions *sfa;
 205
 206         if (size > MAX_ACTIONS_BUFSIZE)
 207                 return ERR_PTR(-EINVAL);
 208
 209         sfa = kmalloc(sizeof(*sfa) + size, GFP_KERNEL);
 210         if (!sfa)
 211                 return ERR_PTR(-ENOMEM);
 212
 213         sfa->actions_len = 0;
 214         return sfa;
 215 }
 216
 217 struct sw_flow *ovs_flow_alloc(void)
 218 {
 219         struct sw_flow *flow;
 220
 221         flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
 222         if (!flow)
 223                 return ERR_PTR(-ENOMEM);
 224
 225         spin_lock_init(&flow->lock);
 226         flow->sf_acts = NULL;
 227
 228         return flow;
 229 }
 230
 231 static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
 232 {
 233         hash = jhash_1word(hash, table->hash_seed);
 234         return flex_array_get(table->buckets,
 235                                 (hash & (table->n_buckets - 1)));
 236 }
 237
 238 static struct flex_array *alloc_buckets(unsigned int n_buckets)
 239 {
 240         struct flex_array *buckets;
 241         int i, err;
 242
 243         buckets = flex_array_alloc(sizeof(struct hlist_head),
 244                                    n_buckets, GFP_KERNEL);
 245         if (!buckets)
 246                 return NULL;
 247
 248         err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
 249         if (err) {
 250                 flex_array_free(buckets);
 251                 return NULL;
 252         }
 253
 254         for (i = 0; i < n_buckets; i++)
 255                 INIT_HLIST_HEAD((struct hlist_head *)
 256                                         flex_array_get(buckets, i));
 257
 258         return buckets;
 259 }
 260
 261 static void free_buckets(struct flex_array *buckets)
 262 {
 263         flex_array_free(buckets);
 264 }
 265
 266 struct flow_table *ovs_flow_tbl_alloc(int new_size)
 267 {
 268         struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
 269
 270         if (!table)
 271                 return NULL;
 272
 273         table->buckets = alloc_buckets(new_size);
 274
 275         if (!table->buckets) {
 276                 kfree(table);
 277                 return NULL;
 278         }
 279         table->n_buckets = new_size;
 280         table->count = 0;
 281         table->node_ver = 0;
 282         table->keep_flows = false;
 283         get_random_bytes(&table->hash_seed, sizeof(u32));
 284
 285         return table;
 286 }
 287
 288 void ovs_flow_tbl_destroy(struct flow_table *table)
 289 {
 290         int i;
 291
 292         if (!table)
 293                 return;
 294
 295         if (table->keep_flows)
 296                 goto skip_flows;
 297
 298         for (i = 0; i < table->n_buckets; i++) {
 299                 struct sw_flow *flow;
 300                 struct hlist_head *head = flex_array_get(table->buckets, i);
 301                 struct hlist_node *n;
 302                 int ver = table->node_ver;
 303
 304                 hlist_for_each_entry_safe(flow, n, head, hash_node[ver]) {
 305                         hlist_del_rcu(&flow->hash_node[ver]);
 306                         ovs_flow_free(flow);
 307                 }
 308         }
 309
 310 skip_flows:
 311         free_buckets(table->buckets);
 312         kfree(table);
 313 }
 314
 315 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
 316 {
 317         struct flow_table *table = container_of(rcu, struct flow_table, rcu);
 318
 319         ovs_flow_tbl_destroy(table);
 320 }
 321
 322 void ovs_flow_tbl_deferred_destroy(struct flow_table *table)
 323 {
 324         if (!table)
 325                 return;
 326
 327         call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
 328 }
 329
 330 struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
 331 {
 332         struct sw_flow *flow;
 333         struct hlist_head *head;
 334         int ver;
 335         int i;
 336
 337         ver = table->node_ver;
 338         while (*bucket < table->n_buckets) {
 339                 i = 0;
 340                 head = flex_array_get(table->buckets, *bucket);
 341                 hlist_for_each_entry_rcu(flow, head, hash_node[ver]) {
 342                         if (i < *last) {
 343                                 i++;
 344                                 continue;
 345                         }
 346                         *last = i + 1;
 347                         return flow;
 348                 }
 349                 (*bucket)++;
 350                 *last = 0;
 351         }
 352
 353         return NULL;
 354 }
 355
 356 static void __flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
 357 {
 358         struct hlist_head *head;
 359         head = find_bucket(table, flow->hash);
 360         hlist_add_head_rcu(&flow->hash_node[table->node_ver], head);
 361         table->count++;
 362 }
 363
 364 static void flow_table_copy_flows(struct flow_table *old, struct flow_table *new)
 365 {
 366         int old_ver;
 367         int i;
 368
 369         old_ver = old->node_ver;
 370         new->node_ver = !old_ver;
 371
 372         /* Insert in new table. */
 373         for (i = 0; i < old->n_buckets; i++) {
 374                 struct sw_flow *flow;
 375                 struct hlist_head *head;
 376
 377                 head = flex_array_get(old->buckets, i);
 378
 379                 hlist_for_each_entry(flow, head, hash_node[old_ver])
 380                         __flow_tbl_insert(new, flow);
 381         }
 382         old->keep_flows = true;
 383 }
 384
 385 static struct flow_table *__flow_tbl_rehash(struct flow_table *table, int n_buckets)
 386 {
 387         struct flow_table *new_table;
 388
 389         new_table = ovs_flow_tbl_alloc(n_buckets);
 390         if (!new_table)
 391                 return ERR_PTR(-ENOMEM);
 392
 393         flow_table_copy_flows(table, new_table);
 394
 395         return new_table;
 396 }
 397
 398 struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table)
 399 {
 400         return __flow_tbl_rehash(table, table->n_buckets);
 401 }
 402
 403 struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
 404 {
 405         return __flow_tbl_rehash(table, table->n_buckets * 2);
 406 }
 407
 408 void ovs_flow_free(struct sw_flow *flow)
 409 {
 410         if (unlikely(!flow))
 411                 return;
 412
 413         kfree((struct sf_flow_acts __force *)flow->sf_acts);
 414         kmem_cache_free(flow_cache, flow);
 415 }
 416
 417 /* RCU callback used by ovs_flow_deferred_free. */
 418 static void rcu_free_flow_callback(struct rcu_head *rcu)
 419 {
 420         struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
 421
 422         ovs_flow_free(flow);
 423 }
 424
 425 /* Schedules 'flow' 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(struct sw_flow *flow)
 428 {
 429         call_rcu(&flow->rcu, rcu_free_flow_callback);
 430 }
 431
 432 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
 433  * The caller must hold rcu_read_lock for this to be sensible. */
 434 void ovs_flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
 435 {
 436         kfree_rcu(sf_acts, rcu);
 437 }
 438
 439 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 440 {
 441         struct qtag_prefix {
 442                 __be16 eth_type; /* ETH_P_8021Q */
 443                 __be16 tci;
 444         };
 445         struct qtag_prefix *qp;
 446
 447         if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
 448                 return 0;
 449
 450         if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
 451                                          sizeof(__be16))))
 452                 return -ENOMEM;
 453
 454         qp = (struct qtag_prefix *) skb->data;
 455         key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
 456         __skb_pull(skb, sizeof(struct qtag_prefix));
 457
 458         return 0;
 459 }
 460
 461 static __be16 parse_ethertype(struct sk_buff *skb)
 462 {
 463         struct llc_snap_hdr {
 464                 u8  dsap;  /* Always 0xAA */
 465                 u8  ssap;  /* Always 0xAA */
 466                 u8  ctrl;
 467                 u8  oui[3];
 468                 __be16 ethertype;
 469         };
 470         struct llc_snap_hdr *llc;
 471         __be16 proto;
 472
 473         proto = *(__be16 *) skb->data;
 474         __skb_pull(skb, sizeof(__be16));
 475
 476         if (ntohs(proto) >= ETH_P_802_3_MIN)
 477                 return proto;
 478
 479         if (skb->len < sizeof(struct llc_snap_hdr))
 480                 return htons(ETH_P_802_2);
 481
 482         if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
 483                 return htons(0);
 484
 485         llc = (struct llc_snap_hdr *) skb->data;
 486         if (llc->dsap != LLC_SAP_SNAP ||
 487             llc->ssap != LLC_SAP_SNAP ||
 488             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
 489                 return htons(ETH_P_802_2);
 490
 491         __skb_pull(skb, sizeof(struct llc_snap_hdr));
 492
 493         if (ntohs(llc->ethertype) >= ETH_P_802_3_MIN)
 494                 return llc->ethertype;
 495
 496         return htons(ETH_P_802_2);
 497 }
 498
 499 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
 500                         int *key_lenp, int nh_len)
 501 {
 502         struct icmp6hdr *icmp = icmp6_hdr(skb);
 503         int error = 0;
 504         int key_len;
 505
 506         /* The ICMPv6 type and code fields use the 16-bit transport port
 507          * fields, so we need to store them in 16-bit network byte order.
 508          */
 509         key->ipv6.tp.src = htons(icmp->icmp6_type);
 510         key->ipv6.tp.dst = htons(icmp->icmp6_code);
 511         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 512
 513         if (icmp->icmp6_code == 0 &&
 514             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
 515              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 516                 int icmp_len = skb->len - skb_transport_offset(skb);
 517                 struct nd_msg *nd;
 518                 int offset;
 519
 520                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 521
 522                 /* In order to process neighbor discovery options, we need the
 523                  * entire packet.
 524                  */
 525                 if (unlikely(icmp_len < sizeof(*nd)))
 526                         goto out;
 527                 if (unlikely(skb_linearize(skb))) {
 528                         error = -ENOMEM;
 529                         goto out;
 530                 }
 531
 532                 nd = (struct nd_msg *)skb_transport_header(skb);
 533                 key->ipv6.nd.target = nd->target;
 534                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 535
 536                 icmp_len -= sizeof(*nd);
 537                 offset = 0;
 538                 while (icmp_len >= 8) {
 539                         struct nd_opt_hdr *nd_opt =
 540                                  (struct nd_opt_hdr *)(nd->opt + offset);
 541                         int opt_len = nd_opt->nd_opt_len * 8;
 542
 543                         if (unlikely(!opt_len || opt_len > icmp_len))
 544                                 goto invalid;
 545
 546                         /* Store the link layer address if the appropriate
 547                          * option is provided.  It is considered an error if
 548                          * the same link layer option is specified twice.
 549                          */
 550                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
 551                             && opt_len == 8) {
 552                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
 553                                         goto invalid;
 554                                 memcpy(key->ipv6.nd.sll,
 555                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 556                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
 557                                    && opt_len == 8) {
 558                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
 559                                         goto invalid;
 560                                 memcpy(key->ipv6.nd.tll,
 561                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 562                         }
 563
 564                         icmp_len -= opt_len;
 565                         offset += opt_len;
 566                 }
 567         }
 568
 569         goto out;
 570
 571 invalid:
 572         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
 573         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
 574         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
 575
 576 out:
 577         *key_lenp = key_len;
 578         return error;
 579 }
 580
 581 /**
 582  * ovs_flow_extract - extracts a flow key from an Ethernet frame.
 583  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 584  * Ethernet header
 585  * @in_port: port number on which @skb was received.
 586  * @key: output flow key
 587  * @key_lenp: length of output flow key
 588  *
 589  * The caller must ensure that skb->len >= ETH_HLEN.
 590  *
 591  * Returns 0 if successful, otherwise a negative errno value.
 592  *
 593  * Initializes @skb header pointers as follows:
 594  *
 595  *    - skb->mac_header: the Ethernet header.
 596  *
 597  *    - skb->network_header: just past the Ethernet header, or just past the
 598  *      VLAN header, to the first byte of the Ethernet payload.
 599  *
 600  *    - skb->transport_header: If key->eth.type is ETH_P_IP or ETH_P_IPV6
 601  *      on output, then just past the IP header, if one is present and
 602  *      of a correct length, otherwise the same as skb->network_header.
 603  *      For other key->eth.type values it is left untouched.
 604  */
 605 int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
 606                  int *key_lenp)
 607 {
 608         int error = 0;
 609         int key_len = SW_FLOW_KEY_OFFSET(eth);
 610         struct ethhdr *eth;
 611
 612         memset(key, 0, sizeof(*key));
 613
 614         key->phy.priority = skb->priority;
 615         if (OVS_CB(skb)->tun_key)
 616                 memcpy(&key->tun_key, OVS_CB(skb)->tun_key, sizeof(key->tun_key));
 617         key->phy.in_port = in_port;
 618         key->phy.skb_mark = skb->mark;
 619
 620         skb_reset_mac_header(skb);
 621
 622         /* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
 623          * header in the linear data area.
 624          */
 625         eth = eth_hdr(skb);
 626         memcpy(key->eth.src, eth->h_source, ETH_ALEN);
 627         memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
 628
 629         __skb_pull(skb, 2 * ETH_ALEN);
 630         /* We are going to push all headers that we pull, so no need to
 631          * update skb->csum here.
 632          */
 633
 634         if (vlan_tx_tag_present(skb))
 635                 key->eth.tci = htons(skb->vlan_tci);
 636         else if (eth->h_proto == htons(ETH_P_8021Q))
 637                 if (unlikely(parse_vlan(skb, key)))
 638                         return -ENOMEM;
 639
 640         key->eth.type = parse_ethertype(skb);
 641         if (unlikely(key->eth.type == htons(0)))
 642                 return -ENOMEM;
 643
 644         skb_reset_network_header(skb);
 645         __skb_push(skb, skb->data - skb_mac_header(skb));
 646
 647         /* Network layer. */
 648         if (key->eth.type == htons(ETH_P_IP)) {
 649                 struct iphdr *nh;
 650                 __be16 offset;
 651
 652                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
 653
 654                 error = check_iphdr(skb);
 655                 if (unlikely(error)) {
 656                         if (error == -EINVAL) {
 657                                 skb->transport_header = skb->network_header;
 658                                 error = 0;
 659                         }
 660                         goto out;
 661                 }
 662
 663                 nh = ip_hdr(skb);
 664                 key->ipv4.addr.src = nh->saddr;
 665                 key->ipv4.addr.dst = nh->daddr;
 666
 667                 key->ip.proto = nh->protocol;
 668                 key->ip.tos = nh->tos;
 669                 key->ip.ttl = nh->ttl;
 670
 671                 offset = nh->frag_off & htons(IP_OFFSET);
 672                 if (offset) {
 673                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 674                         goto out;
 675                 }
 676                 if (nh->frag_off & htons(IP_MF) ||
 677                          skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 678                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 679
 680                 /* Transport layer. */
 681                 if (key->ip.proto == IPPROTO_TCP) {
 682                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 683                         if (tcphdr_ok(skb)) {
 684                                 struct tcphdr *tcp = tcp_hdr(skb);
 685                                 key->ipv4.tp.src = tcp->source;
 686                                 key->ipv4.tp.dst = tcp->dest;
 687                         }
 688                 } else if (key->ip.proto == IPPROTO_UDP) {
 689                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 690                         if (udphdr_ok(skb)) {
 691                                 struct udphdr *udp = udp_hdr(skb);
 692                                 key->ipv4.tp.src = udp->source;
 693                                 key->ipv4.tp.dst = udp->dest;
 694                         }
 695                 } else if (key->ip.proto == IPPROTO_ICMP) {
 696                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 697                         if (icmphdr_ok(skb)) {
 698                                 struct icmphdr *icmp = icmp_hdr(skb);
 699                                 /* The ICMP type and code fields use the 16-bit
 700                                  * transport port fields, so we need to store
 701                                  * them in 16-bit network byte order. */
 702                                 key->ipv4.tp.src = htons(icmp->type);
 703                                 key->ipv4.tp.dst = htons(icmp->code);
 704                         }
 705                 }
 706
 707         } else if ((key->eth.type == htons(ETH_P_ARP) ||
 708                    key->eth.type == htons(ETH_P_RARP)) && arphdr_ok(skb)) {
 709                 struct arp_eth_header *arp;
 710
 711                 arp = (struct arp_eth_header *)skb_network_header(skb);
 712
 713                 if (arp->ar_hrd == htons(ARPHRD_ETHER)
 714                                 && arp->ar_pro == htons(ETH_P_IP)
 715                                 && arp->ar_hln == ETH_ALEN
 716                                 && arp->ar_pln == 4) {
 717
 718                         /* We only match on the lower 8 bits of the opcode. */
 719                         if (ntohs(arp->ar_op) <= 0xff)
 720                                 key->ip.proto = ntohs(arp->ar_op);
 721                         memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
 722                         memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
 723                         memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
 724                         memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
 725                         key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
 726                 }
 727         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 728                 int nh_len;             /* IPv6 Header + Extensions */
 729
 730                 nh_len = parse_ipv6hdr(skb, key, &key_len);
 731                 if (unlikely(nh_len < 0)) {
 732                         if (nh_len == -EINVAL)
 733                                 skb->transport_header = skb->network_header;
 734                         else
 735                                 error = nh_len;
 736                         goto out;
 737                 }
 738
 739                 if (key->ip.frag == OVS_FRAG_TYPE_LATER)
 740                         goto out;
 741                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 742                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 743
 744                 /* Transport layer. */
 745                 if (key->ip.proto == NEXTHDR_TCP) {
 746                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 747                         if (tcphdr_ok(skb)) {
 748                                 struct tcphdr *tcp = tcp_hdr(skb);
 749                                 key->ipv6.tp.src = tcp->source;
 750                                 key->ipv6.tp.dst = tcp->dest;
 751                         }
 752                 } else if (key->ip.proto == NEXTHDR_UDP) {
 753                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 754                         if (udphdr_ok(skb)) {
 755                                 struct udphdr *udp = udp_hdr(skb);
 756                                 key->ipv6.tp.src = udp->source;
 757                                 key->ipv6.tp.dst = udp->dest;
 758                         }
 759                 } else if (key->ip.proto == NEXTHDR_ICMP) {
 760                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 761                         if (icmp6hdr_ok(skb)) {
 762                                 error = parse_icmpv6(skb, key, &key_len, nh_len);
 763                                 if (error < 0)
 764                                         goto out;
 765                         }
 766                 }
 767         }
 768
 769 out:
 770         *key_lenp = key_len;
 771         return error;
 772 }
 773
 774 static u32 ovs_flow_hash(const struct sw_flow_key *key, int key_start, int key_len)
 775 {
 776         return jhash2((u32 *)((u8 *)key + key_start),
 777                       DIV_ROUND_UP(key_len - key_start, sizeof(u32)), 0);
 778 }
 779
 780 static int flow_key_start(struct sw_flow_key *key)
 781 {
 782         if (key->tun_key.ipv4_dst)
 783                 return 0;
 784         else
 785                 return offsetof(struct sw_flow_key, phy);
 786 }
 787
 788 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
 789                                 struct sw_flow_key *key, int key_len)
 790 {
 791         struct sw_flow *flow;
 792         struct hlist_head *head;
 793         u8 *_key;
 794         int key_start;
 795         u32 hash;
 796
 797         key_start = flow_key_start(key);
 798         hash = ovs_flow_hash(key, key_start, key_len);
 799
 800         _key = (u8 *) key + key_start;
 801         head = find_bucket(table, hash);
 802         hlist_for_each_entry_rcu(flow, head, hash_node[table->node_ver]) {
 803
 804                 if (flow->hash == hash &&
 805                     !memcmp((u8 *)&flow->key + key_start, _key, key_len - key_start)) {
 806                         return flow;
 807                 }
 808         }
 809         return NULL;
 810 }
 811
 812 void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow,
 813                          struct sw_flow_key *key, int key_len)
 814 {
 815         flow->hash = ovs_flow_hash(key, flow_key_start(key), key_len);
 816         memcpy(&flow->key, key, sizeof(flow->key));
 817         __flow_tbl_insert(table, flow);
 818 }
 819
 820 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
 821 {
 822         BUG_ON(table->count == 0);
 823         hlist_del_rcu(&flow->hash_node[table->node_ver]);
 824         table->count--;
 825 }
 826
 827 /* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
 828 const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
 829         [OVS_KEY_ATTR_ENCAP] = -1,
 830         [OVS_KEY_ATTR_PRIORITY] = sizeof(u32),
 831         [OVS_KEY_ATTR_IN_PORT] = sizeof(u32),
 832         [OVS_KEY_ATTR_SKB_MARK] = sizeof(u32),
 833         [OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
 834         [OVS_KEY_ATTR_VLAN] = sizeof(__be16),
 835         [OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
 836         [OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
 837         [OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
 838         [OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
 839         [OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
 840         [OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
 841         [OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
 842         [OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
 843         [OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
 844         [OVS_KEY_ATTR_TUNNEL] = -1,
 845 };
 846
 847 static int ipv4_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 848                                   const struct nlattr *a[], u32 *attrs)
 849 {
 850         const struct ovs_key_icmp *icmp_key;
 851         const struct ovs_key_tcp *tcp_key;
 852         const struct ovs_key_udp *udp_key;
 853
 854         switch (swkey->ip.proto) {
 855         case IPPROTO_TCP:
 856                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 857                         return -EINVAL;
 858                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 859
 860                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 861                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 862                 swkey->ipv4.tp.src = tcp_key->tcp_src;
 863                 swkey->ipv4.tp.dst = tcp_key->tcp_dst;
 864                 break;
 865
 866         case IPPROTO_UDP:
 867                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 868                         return -EINVAL;
 869                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 870
 871                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 872                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 873                 swkey->ipv4.tp.src = udp_key->udp_src;
 874                 swkey->ipv4.tp.dst = udp_key->udp_dst;
 875                 break;
 876
 877         case IPPROTO_ICMP:
 878                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMP)))
 879                         return -EINVAL;
 880                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
 881
 882                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 883                 icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
 884                 swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
 885                 swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
 886                 break;
 887         }
 888
 889         return 0;
 890 }
 891
 892 static int ipv6_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 893                                   const struct nlattr *a[], u32 *attrs)
 894 {
 895         const struct ovs_key_icmpv6 *icmpv6_key;
 896         const struct ovs_key_tcp *tcp_key;
 897         const struct ovs_key_udp *udp_key;
 898
 899         switch (swkey->ip.proto) {
 900         case IPPROTO_TCP:
 901                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 902                         return -EINVAL;
 903                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 904
 905                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 906                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 907                 swkey->ipv6.tp.src = tcp_key->tcp_src;
 908                 swkey->ipv6.tp.dst = tcp_key->tcp_dst;
 909                 break;
 910
 911         case IPPROTO_UDP:
 912                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 913                         return -EINVAL;
 914                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 915
 916                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 917                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 918                 swkey->ipv6.tp.src = udp_key->udp_src;
 919                 swkey->ipv6.tp.dst = udp_key->udp_dst;
 920                 break;
 921
 922         case IPPROTO_ICMPV6:
 923                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMPV6)))
 924                         return -EINVAL;
 925                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
 926
 927                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 928                 icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
 929                 swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
 930                 swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
 931
 932                 if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
 933                     swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 934                         const struct ovs_key_nd *nd_key;
 935
 936                         if (!(*attrs & (1 << OVS_KEY_ATTR_ND)))
 937                                 return -EINVAL;
 938                         *attrs &= ~(1 << OVS_KEY_ATTR_ND);
 939
 940                         *key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 941                         nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
 942                         memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
 943                                sizeof(swkey->ipv6.nd.target));
 944                         memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
 945                         memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
 946                 }
 947                 break;
 948         }
 949
 950         return 0;
 951 }
 952
 953 static int parse_flow_nlattrs(const struct nlattr *attr,
 954                               const struct nlattr *a[], u32 *attrsp)
 955 {
 956         const struct nlattr *nla;
 957         u32 attrs;
 958         int rem;
 959
 960         attrs = 0;
 961         nla_for_each_nested(nla, attr, rem) {
 962                 u16 type = nla_type(nla);
 963                 int expected_len;
 964
 965                 if (type > OVS_KEY_ATTR_MAX || attrs & (1 << type))
 966                         return -EINVAL;
 967
 968                 expected_len = ovs_key_lens[type];
 969                 if (nla_len(nla) != expected_len && expected_len != -1)
 970                         return -EINVAL;
 971
 972                 attrs |= 1 << type;
 973                 a[type] = nla;
 974         }
 975         if (rem)
 976                 return -EINVAL;
 977
 978         *attrsp = attrs;
 979         return 0;
 980 }
 981
 982 int ovs_ipv4_tun_from_nlattr(const struct nlattr *attr,
 983                              struct ovs_key_ipv4_tunnel *tun_key)
 984 {
 985         struct nlattr *a;
 986         int rem;
 987         bool ttl = false;
 988
 989         memset(tun_key, 0, sizeof(*tun_key));
 990
 991         nla_for_each_nested(a, attr, rem) {
 992                 int type = nla_type(a);
 993                 static const u32 ovs_tunnel_key_lens[OVS_TUNNEL_KEY_ATTR_MAX + 1] = {
 994                         [OVS_TUNNEL_KEY_ATTR_ID] = sizeof(u64),
 995                         [OVS_TUNNEL_KEY_ATTR_IPV4_SRC] = sizeof(u32),
 996                         [OVS_TUNNEL_KEY_ATTR_IPV4_DST] = sizeof(u32),
 997                         [OVS_TUNNEL_KEY_ATTR_TOS] = 1,
 998                         [OVS_TUNNEL_KEY_ATTR_TTL] = 1,
 999                         [OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT] = 0,
1000                         [OVS_TUNNEL_KEY_ATTR_CSUM] = 0,
1001                 };
1002
1003                 if (type > OVS_TUNNEL_KEY_ATTR_MAX ||
1004                         ovs_tunnel_key_lens[type] != nla_len(a))
1005                         return -EINVAL;
1006
1007                 switch (type) {
1008                 case OVS_TUNNEL_KEY_ATTR_ID:
1009                         tun_key->tun_id = nla_get_be64(a);
1010                         tun_key->tun_flags |= TUNNEL_KEY;
1011                         break;
1012                 case OVS_TUNNEL_KEY_ATTR_IPV4_SRC:
1013                         tun_key->ipv4_src = nla_get_be32(a);
1014                         break;
1015                 case OVS_TUNNEL_KEY_ATTR_IPV4_DST:
1016                         tun_key->ipv4_dst = nla_get_be32(a);
1017                         break;
1018                 case OVS_TUNNEL_KEY_ATTR_TOS:
1019                         tun_key->ipv4_tos = nla_get_u8(a);
1020                         break;
1021                 case OVS_TUNNEL_KEY_ATTR_TTL:
1022                         tun_key->ipv4_ttl = nla_get_u8(a);
1023                         ttl = true;
1024                         break;
1025                 case OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT:
1026                         tun_key->tun_flags |= TUNNEL_DONT_FRAGMENT;
1027                         break;
1028                 case OVS_TUNNEL_KEY_ATTR_CSUM:
1029                         tun_key->tun_flags |= TUNNEL_CSUM;
1030                         break;
1031                 default:
1032                         return -EINVAL;
1033
1034                 }
1035         }
1036         if (rem > 0)
1037                 return -EINVAL;
1038
1039         if (!tun_key->ipv4_dst)
1040                 return -EINVAL;
1041
1042         if (!ttl)
1043                 return -EINVAL;
1044
1045         return 0;
1046 }
1047
1048 int ovs_ipv4_tun_to_nlattr(struct sk_buff *skb,
1049                            const struct ovs_key_ipv4_tunnel *tun_key)
1050 {
1051         struct nlattr *nla;
1052
1053         nla = nla_nest_start(skb, OVS_KEY_ATTR_TUNNEL);
1054         if (!nla)
1055                 return -EMSGSIZE;
1056
1057         if (tun_key->tun_flags & TUNNEL_KEY &&
1058             nla_put_be64(skb, OVS_TUNNEL_KEY_ATTR_ID, tun_key->tun_id))
1059                 return -EMSGSIZE;
1060         if (tun_key->ipv4_src &&
1061             nla_put_be32(skb, OVS_TUNNEL_KEY_ATTR_IPV4_SRC, tun_key->ipv4_src))
1062                 return -EMSGSIZE;
1063         if (nla_put_be32(skb, OVS_TUNNEL_KEY_ATTR_IPV4_DST, tun_key->ipv4_dst))
1064                 return -EMSGSIZE;
1065         if (tun_key->ipv4_tos &&
1066             nla_put_u8(skb, OVS_TUNNEL_KEY_ATTR_TOS, tun_key->ipv4_tos))
1067                 return -EMSGSIZE;
1068         if (nla_put_u8(skb, OVS_TUNNEL_KEY_ATTR_TTL, tun_key->ipv4_ttl))
1069                 return -EMSGSIZE;
1070         if ((tun_key->tun_flags & TUNNEL_DONT_FRAGMENT) &&
1071                 nla_put_flag(skb, OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT))
1072                 return -EMSGSIZE;
1073         if ((tun_key->tun_flags & TUNNEL_CSUM) &&
1074                 nla_put_flag(skb, OVS_TUNNEL_KEY_ATTR_CSUM))
1075                 return -EMSGSIZE;
1076
1077         nla_nest_end(skb, nla);
1078         return 0;
1079 }
1080
1081 /**
1082  * ovs_flow_from_nlattrs - parses Netlink attributes into a flow key.
1083  * @swkey: receives the extracted flow key.
1084  * @key_lenp: number of bytes used in @swkey.
1085  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1086  * sequence.
1087  */
1088 int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
1089                       const struct nlattr *attr)
1090 {
1091         const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
1092         const struct ovs_key_ethernet *eth_key;
1093         int key_len;
1094         u32 attrs;
1095         int err;
1096
1097         memset(swkey, 0, sizeof(struct sw_flow_key));
1098         key_len = SW_FLOW_KEY_OFFSET(eth);
1099
1100         err = parse_flow_nlattrs(attr, a, &attrs);
1101         if (err)
1102                 return err;
1103
1104         /* Metadata attributes. */
1105         if (attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
1106                 swkey->phy.priority = nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]);
1107                 attrs &= ~(1 << OVS_KEY_ATTR_PRIORITY);
1108         }
1109         if (attrs & (1 << OVS_KEY_ATTR_IN_PORT)) {
1110                 u32 in_port = nla_get_u32(a[OVS_KEY_ATTR_IN_PORT]);
1111                 if (in_port >= DP_MAX_PORTS)
1112                         return -EINVAL;
1113                 swkey->phy.in_port = in_port;
1114                 attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
1115         } else {
1116                 swkey->phy.in_port = DP_MAX_PORTS;
1117         }
1118         if (attrs & (1 << OVS_KEY_ATTR_SKB_MARK)) {
1119                 swkey->phy.skb_mark = nla_get_u32(a[OVS_KEY_ATTR_SKB_MARK]);
1120                 attrs &= ~(1 << OVS_KEY_ATTR_SKB_MARK);
1121         }
1122
1123         if (attrs & (1 << OVS_KEY_ATTR_TUNNEL)) {
1124                 err = ovs_ipv4_tun_from_nlattr(a[OVS_KEY_ATTR_TUNNEL], &swkey->tun_key);
1125                 if (err)
1126                         return err;
1127
1128                 attrs &= ~(1 << OVS_KEY_ATTR_TUNNEL);
1129         }
1130
1131         /* Data attributes. */
1132         if (!(attrs & (1 << OVS_KEY_ATTR_ETHERNET)))
1133                 return -EINVAL;
1134         attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
1135
1136         eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
1137         memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
1138         memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
1139
1140         if (attrs & (1u << OVS_KEY_ATTR_ETHERTYPE) &&
1141             nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q)) {
1142                 const struct nlattr *encap;
1143                 __be16 tci;
1144
1145                 if (attrs != ((1 << OVS_KEY_ATTR_VLAN) |
1146                               (1 << OVS_KEY_ATTR_ETHERTYPE) |
1147                               (1 << OVS_KEY_ATTR_ENCAP)))
1148                         return -EINVAL;
1149
1150                 encap = a[OVS_KEY_ATTR_ENCAP];
1151                 tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
1152                 if (tci & htons(VLAN_TAG_PRESENT)) {
1153                         swkey->eth.tci = tci;
1154
1155                         err = parse_flow_nlattrs(encap, a, &attrs);
1156                         if (err)
1157                                 return err;
1158                 } else if (!tci) {
1159                         /* Corner case for truncated 802.1Q header. */
1160                         if (nla_len(encap))
1161                                 return -EINVAL;
1162
1163                         swkey->eth.type = htons(ETH_P_8021Q);
1164                         *key_lenp = key_len;
1165                         return 0;
1166                 } else {
1167                         return -EINVAL;
1168                 }
1169         }
1170
1171         if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
1172                 swkey->eth.type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
1173                 if (ntohs(swkey->eth.type) < ETH_P_802_3_MIN)
1174                         return -EINVAL;
1175                 attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
1176         } else {
1177                 swkey->eth.type = htons(ETH_P_802_2);
1178         }
1179
1180         if (swkey->eth.type == htons(ETH_P_IP)) {
1181                 const struct ovs_key_ipv4 *ipv4_key;
1182
1183                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV4)))
1184                         return -EINVAL;
1185                 attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
1186
1187                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
1188                 ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
1189                 if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
1190                         return -EINVAL;
1191                 swkey->ip.proto = ipv4_key->ipv4_proto;
1192                 swkey->ip.tos = ipv4_key->ipv4_tos;
1193                 swkey->ip.ttl = ipv4_key->ipv4_ttl;
1194                 swkey->ip.frag = ipv4_key->ipv4_frag;
1195                 swkey->ipv4.addr.src = ipv4_key->ipv4_src;
1196                 swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
1197
1198                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1199                         err = ipv4_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1200                         if (err)
1201                                 return err;
1202                 }
1203         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1204                 const struct ovs_key_ipv6 *ipv6_key;
1205
1206                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV6)))
1207                         return -EINVAL;
1208                 attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
1209
1210                 key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
1211                 ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
1212                 if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
1213                         return -EINVAL;
1214                 swkey->ipv6.label = ipv6_key->ipv6_label;
1215                 swkey->ip.proto = ipv6_key->ipv6_proto;
1216                 swkey->ip.tos = ipv6_key->ipv6_tclass;
1217                 swkey->ip.ttl = ipv6_key->ipv6_hlimit;
1218                 swkey->ip.frag = ipv6_key->ipv6_frag;
1219                 memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
1220                        sizeof(swkey->ipv6.addr.src));
1221                 memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
1222                        sizeof(swkey->ipv6.addr.dst));
1223
1224                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1225                         err = ipv6_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1226                         if (err)
1227                                 return err;
1228                 }
1229         } else if (swkey->eth.type == htons(ETH_P_ARP) ||
1230                    swkey->eth.type == htons(ETH_P_RARP)) {
1231                 const struct ovs_key_arp *arp_key;
1232
1233                 if (!(attrs & (1 << OVS_KEY_ATTR_ARP)))
1234                         return -EINVAL;
1235                 attrs &= ~(1 << OVS_KEY_ATTR_ARP);
1236
1237                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
1238                 arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
1239                 swkey->ipv4.addr.src = arp_key->arp_sip;
1240                 swkey->ipv4.addr.dst = arp_key->arp_tip;
1241                 if (arp_key->arp_op & htons(0xff00))
1242                         return -EINVAL;
1243                 swkey->ip.proto = ntohs(arp_key->arp_op);
1244                 memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
1245                 memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
1246         }
1247
1248         if (attrs)
1249                 return -EINVAL;
1250         *key_lenp = key_len;
1251
1252         return 0;
1253 }
1254
1255 /**
1256  * ovs_flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
1257  * @flow: Receives extracted in_port, priority, tun_key and skb_mark.
1258  * @key_len: Length of key in @flow.  Used for calculating flow hash.
1259  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1260  * sequence.
1261  *
1262  * This parses a series of Netlink attributes that form a flow key, which must
1263  * take the same form accepted by flow_from_nlattrs(), but only enough of it to
1264  * get the metadata, that is, the parts of the flow key that cannot be
1265  * extracted from the packet itself.
1266  */
1267 int ovs_flow_metadata_from_nlattrs(struct sw_flow *flow, int key_len,
1268                                    const struct nlattr *attr)
1269 {
1270         struct ovs_key_ipv4_tunnel *tun_key = &flow->key.tun_key;
1271         const struct nlattr *nla;
1272         int rem;
1273
1274         flow->key.phy.in_port = DP_MAX_PORTS;
1275         flow->key.phy.priority = 0;
1276         flow->key.phy.skb_mark = 0;
1277         memset(tun_key, 0, sizeof(flow->key.tun_key));
1278
1279         nla_for_each_nested(nla, attr, rem) {
1280                 int type = nla_type(nla);
1281
1282                 if (type <= OVS_KEY_ATTR_MAX && ovs_key_lens[type] > 0) {
1283                         int err;
1284
1285                         if (nla_len(nla) != ovs_key_lens[type])
1286                                 return -EINVAL;
1287
1288                         switch (type) {
1289                         case OVS_KEY_ATTR_PRIORITY:
1290                                 flow->key.phy.priority = nla_get_u32(nla);
1291                                 break;
1292
1293                         case OVS_KEY_ATTR_TUNNEL:
1294                                 err = ovs_ipv4_tun_from_nlattr(nla, tun_key);
1295                                 if (err)
1296                                         return err;
1297                                 break;
1298
1299                         case OVS_KEY_ATTR_IN_PORT:
1300                                 if (nla_get_u32(nla) >= DP_MAX_PORTS)
1301                                         return -EINVAL;
1302                                 flow->key.phy.in_port = nla_get_u32(nla);
1303                                 break;
1304
1305                         case OVS_KEY_ATTR_SKB_MARK:
1306                                 flow->key.phy.skb_mark = nla_get_u32(nla);
1307                                 break;
1308                         }
1309                 }
1310         }
1311         if (rem)
1312                 return -EINVAL;
1313
1314         flow->hash = ovs_flow_hash(&flow->key,
1315                                    flow_key_start(&flow->key), key_len);
1316
1317         return 0;
1318 }
1319
1320 int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
1321 {
1322         struct ovs_key_ethernet *eth_key;
1323         struct nlattr *nla, *encap;
1324
1325         if (swkey->phy.priority &&
1326             nla_put_u32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority))
1327                 goto nla_put_failure;
1328
1329         if (swkey->tun_key.ipv4_dst &&
1330             ovs_ipv4_tun_to_nlattr(skb, &swkey->tun_key))
1331                 goto nla_put_failure;
1332
1333         if (swkey->phy.in_port != DP_MAX_PORTS &&
1334             nla_put_u32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port))
1335                 goto nla_put_failure;
1336
1337         if (swkey->phy.skb_mark &&
1338             nla_put_u32(skb, OVS_KEY_ATTR_SKB_MARK, swkey->phy.skb_mark))
1339                 goto nla_put_failure;
1340
1341         nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
1342         if (!nla)
1343                 goto nla_put_failure;
1344         eth_key = nla_data(nla);
1345         memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
1346         memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
1347
1348         if (swkey->eth.tci || swkey->eth.type == htons(ETH_P_8021Q)) {
1349                 if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, htons(ETH_P_8021Q)) ||
1350                     nla_put_be16(skb, OVS_KEY_ATTR_VLAN, swkey->eth.tci))
1351                         goto nla_put_failure;
1352                 encap = nla_nest_start(skb, OVS_KEY_ATTR_ENCAP);
1353                 if (!swkey->eth.tci)
1354                         goto unencap;
1355         } else {
1356                 encap = NULL;
1357         }
1358
1359         if (swkey->eth.type == htons(ETH_P_802_2))
1360                 goto unencap;
1361
1362         if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type))
1363                 goto nla_put_failure;
1364
1365         if (swkey->eth.type == htons(ETH_P_IP)) {
1366                 struct ovs_key_ipv4 *ipv4_key;
1367
1368                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
1369                 if (!nla)
1370                         goto nla_put_failure;
1371                 ipv4_key = nla_data(nla);
1372                 ipv4_key->ipv4_src = swkey->ipv4.addr.src;
1373                 ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
1374                 ipv4_key->ipv4_proto = swkey->ip.proto;
1375                 ipv4_key->ipv4_tos = swkey->ip.tos;
1376                 ipv4_key->ipv4_ttl = swkey->ip.ttl;
1377                 ipv4_key->ipv4_frag = swkey->ip.frag;
1378         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1379                 struct ovs_key_ipv6 *ipv6_key;
1380
1381                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
1382                 if (!nla)
1383                         goto nla_put_failure;
1384                 ipv6_key = nla_data(nla);
1385                 memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
1386                                 sizeof(ipv6_key->ipv6_src));
1387                 memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
1388                                 sizeof(ipv6_key->ipv6_dst));
1389                 ipv6_key->ipv6_label = swkey->ipv6.label;
1390                 ipv6_key->ipv6_proto = swkey->ip.proto;
1391                 ipv6_key->ipv6_tclass = swkey->ip.tos;
1392                 ipv6_key->ipv6_hlimit = swkey->ip.ttl;
1393                 ipv6_key->ipv6_frag = swkey->ip.frag;
1394         } else if (swkey->eth.type == htons(ETH_P_ARP) ||
1395                    swkey->eth.type == htons(ETH_P_RARP)) {
1396                 struct ovs_key_arp *arp_key;
1397
1398                 nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
1399                 if (!nla)
1400                         goto nla_put_failure;
1401                 arp_key = nla_data(nla);
1402                 memset(arp_key, 0, sizeof(struct ovs_key_arp));
1403                 arp_key->arp_sip = swkey->ipv4.addr.src;
1404                 arp_key->arp_tip = swkey->ipv4.addr.dst;
1405                 arp_key->arp_op = htons(swkey->ip.proto);
1406                 memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1407                 memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1408         }
1409
1410         if ((swkey->eth.type == htons(ETH_P_IP) ||
1411              swkey->eth.type == htons(ETH_P_IPV6)) &&
1412              swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1413
1414                 if (swkey->ip.proto == IPPROTO_TCP) {
1415                         struct ovs_key_tcp *tcp_key;
1416
1417                         nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
1418                         if (!nla)
1419                                 goto nla_put_failure;
1420                         tcp_key = nla_data(nla);
1421                         if (swkey->eth.type == htons(ETH_P_IP)) {
1422                                 tcp_key->tcp_src = swkey->ipv4.tp.src;
1423                                 tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1424                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1425                                 tcp_key->tcp_src = swkey->ipv6.tp.src;
1426                                 tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1427                         }
1428                 } else if (swkey->ip.proto == IPPROTO_UDP) {
1429                         struct ovs_key_udp *udp_key;
1430
1431                         nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
1432                         if (!nla)
1433                                 goto nla_put_failure;
1434                         udp_key = nla_data(nla);
1435                         if (swkey->eth.type == htons(ETH_P_IP)) {
1436                                 udp_key->udp_src = swkey->ipv4.tp.src;
1437                                 udp_key->udp_dst = swkey->ipv4.tp.dst;
1438                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1439                                 udp_key->udp_src = swkey->ipv6.tp.src;
1440                                 udp_key->udp_dst = swkey->ipv6.tp.dst;
1441                         }
1442                 } else if (swkey->eth.type == htons(ETH_P_IP) &&
1443                            swkey->ip.proto == IPPROTO_ICMP) {
1444                         struct ovs_key_icmp *icmp_key;
1445
1446                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
1447                         if (!nla)
1448                                 goto nla_put_failure;
1449                         icmp_key = nla_data(nla);
1450                         icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1451                         icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1452                 } else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1453                            swkey->ip.proto == IPPROTO_ICMPV6) {
1454                         struct ovs_key_icmpv6 *icmpv6_key;
1455
1456                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
1457                                                 sizeof(*icmpv6_key));
1458                         if (!nla)
1459                                 goto nla_put_failure;
1460                         icmpv6_key = nla_data(nla);
1461                         icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1462                         icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1463
1464                         if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1465                             icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1466                                 struct ovs_key_nd *nd_key;
1467
1468                                 nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
1469                                 if (!nla)
1470                                         goto nla_put_failure;
1471                                 nd_key = nla_data(nla);
1472                                 memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1473                                                         sizeof(nd_key->nd_target));
1474                                 memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1475                                 memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1476                         }
1477                 }
1478         }
1479
1480 unencap:
1481         if (encap)
1482                 nla_nest_end(skb, encap);
1483
1484         return 0;
1485
1486 nla_put_failure:
1487         return -EMSGSIZE;
1488 }
1489
1490 /* Initializes the flow module.
1491  * Returns zero if successful or a negative error code. */
1492 int ovs_flow_init(void)
1493 {
1494         flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1495                                         0, NULL);
1496         if (flow_cache == NULL)
1497                 return -ENOMEM;
1498
1499         return 0;
1500 }
1501
1502 /* Uninitializes the flow module. */
1503 void ovs_flow_exit(void)
1504 {
1505         kmem_cache_destroy(flow_cache);
1506 }