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/ip.h>
  36 #include <linux/ipv6.h>
  37 #include <linux/tcp.h>
  38 #include <linux/udp.h>
  39 #include <linux/icmp.h>
  40 #include <linux/icmpv6.h>
  41 #include <linux/rculist.h>
  42 #include <net/ip.h>
  43 #include <net/ipv6.h>
  44 #include <net/ndisc.h>
  45
  46 #include "vlan.h"
  47
  48 static struct kmem_cache *flow_cache;
  49
  50 static int check_header(struct sk_buff *skb, int len)
  51 {
  52         if (unlikely(skb->len < len))
  53                 return -EINVAL;
  54         if (unlikely(!pskb_may_pull(skb, len)))
  55                 return -ENOMEM;
  56         return 0;
  57 }
  58
  59 static bool arphdr_ok(struct sk_buff *skb)
  60 {
  61         return pskb_may_pull(skb, skb_network_offset(skb) +
  62                                   sizeof(struct arp_eth_header));
  63 }
  64
  65 static int check_iphdr(struct sk_buff *skb)
  66 {
  67         unsigned int nh_ofs = skb_network_offset(skb);
  68         unsigned int ip_len;
  69         int err;
  70
  71         err = check_header(skb, nh_ofs + sizeof(struct iphdr));
  72         if (unlikely(err))
  73                 return err;
  74
  75         ip_len = ip_hdrlen(skb);
  76         if (unlikely(ip_len < sizeof(struct iphdr) ||
  77                      skb->len < nh_ofs + ip_len))
  78                 return -EINVAL;
  79
  80         skb_set_transport_header(skb, nh_ofs + ip_len);
  81         return 0;
  82 }
  83
  84 static bool tcphdr_ok(struct sk_buff *skb)
  85 {
  86         int th_ofs = skb_transport_offset(skb);
  87         int tcp_len;
  88
  89         if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
  90                 return false;
  91
  92         tcp_len = tcp_hdrlen(skb);
  93         if (unlikely(tcp_len < sizeof(struct tcphdr) ||
  94                      skb->len < th_ofs + tcp_len))
  95                 return false;
  96
  97         return true;
  98 }
  99
 100 static bool udphdr_ok(struct sk_buff *skb)
 101 {
 102         return pskb_may_pull(skb, skb_transport_offset(skb) +
 103                                   sizeof(struct udphdr));
 104 }
 105
 106 static bool icmphdr_ok(struct sk_buff *skb)
 107 {
 108         return pskb_may_pull(skb, skb_transport_offset(skb) +
 109                                   sizeof(struct icmphdr));
 110 }
 111
 112 u64 ovs_flow_used_time(unsigned long flow_jiffies)
 113 {
 114         struct timespec cur_ts;
 115         u64 cur_ms, idle_ms;
 116
 117         ktime_get_ts(&cur_ts);
 118         idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
 119         cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
 120                  cur_ts.tv_nsec / NSEC_PER_MSEC;
 121
 122         return cur_ms - idle_ms;
 123 }
 124
 125 #define SW_FLOW_KEY_OFFSET(field)               \
 126         (offsetof(struct sw_flow_key, field) +  \
 127          FIELD_SIZEOF(struct sw_flow_key, field))
 128
 129 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key,
 130                          int *key_lenp)
 131 {
 132         unsigned int nh_ofs = skb_network_offset(skb);
 133         unsigned int nh_len;
 134         int payload_ofs;
 135         struct ipv6hdr *nh;
 136         uint8_t nexthdr;
 137         __be16 frag_off;
 138         int err;
 139
 140         *key_lenp = SW_FLOW_KEY_OFFSET(ipv6.label);
 141
 142         err = check_header(skb, nh_ofs + sizeof(*nh));
 143         if (unlikely(err))
 144                 return err;
 145
 146         nh = ipv6_hdr(skb);
 147         nexthdr = nh->nexthdr;
 148         payload_ofs = (u8 *)(nh + 1) - skb->data;
 149
 150         key->ip.proto = NEXTHDR_NONE;
 151         key->ip.tos = ipv6_get_dsfield(nh);
 152         key->ip.ttl = nh->hop_limit;
 153         key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 154         key->ipv6.addr.src = nh->saddr;
 155         key->ipv6.addr.dst = nh->daddr;
 156
 157         payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
 158         if (unlikely(payload_ofs < 0))
 159                 return -EINVAL;
 160
 161         if (frag_off) {
 162                 if (frag_off & htons(~0x7))
 163                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 164                 else
 165                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 166         }
 167
 168         nh_len = payload_ofs - nh_ofs;
 169         skb_set_transport_header(skb, nh_ofs + nh_len);
 170         key->ip.proto = nexthdr;
 171         return nh_len;
 172 }
 173
 174 static bool icmp6hdr_ok(struct sk_buff *skb)
 175 {
 176         return pskb_may_pull(skb, skb_transport_offset(skb) +
 177                                   sizeof(struct icmp6hdr));
 178 }
 179
 180 #define TCP_FLAGS_OFFSET 13
 181 #define TCP_FLAG_MASK 0x3f
 182
 183 void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb)
 184 {
 185         u8 tcp_flags = 0;
 186
 187         if (flow->key.eth.type == htons(ETH_P_IP) &&
 188             flow->key.ip.proto == IPPROTO_TCP) {
 189                 u8 *tcp = (u8 *)tcp_hdr(skb);
 190                 tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
 191         }
 192
 193         spin_lock(&flow->lock);
 194         flow->used = jiffies;
 195         flow->packet_count++;
 196         flow->byte_count += skb->len;
 197         flow->tcp_flags |= tcp_flags;
 198         spin_unlock(&flow->lock);
 199 }
 200
 201 struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *actions)
 202 {
 203         int actions_len = nla_len(actions);
 204         struct sw_flow_actions *sfa;
 205
 206         /* At least DP_MAX_PORTS actions are required to be able to flood a
 207          * packet to every port.  Factor of 2 allows for setting VLAN tags,
 208          * etc. */
 209         if (actions_len > 2 * DP_MAX_PORTS * nla_total_size(4))
 210                 return ERR_PTR(-EINVAL);
 211
 212         sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
 213         if (!sfa)
 214                 return ERR_PTR(-ENOMEM);
 215
 216         sfa->actions_len = actions_len;
 217         memcpy(sfa->actions, nla_data(actions), actions_len);
 218         return sfa;
 219 }
 220
 221 struct sw_flow *ovs_flow_alloc(void)
 222 {
 223         struct sw_flow *flow;
 224
 225         flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
 226         if (!flow)
 227                 return ERR_PTR(-ENOMEM);
 228
 229         spin_lock_init(&flow->lock);
 230         atomic_set(&flow->refcnt, 1);
 231         flow->sf_acts = NULL;
 232         flow->dead = false;
 233
 234         return flow;
 235 }
 236
 237 static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
 238 {
 239         hash = jhash_1word(hash, table->hash_seed);
 240         return flex_array_get(table->buckets,
 241                                 (hash & (table->n_buckets - 1)));
 242 }
 243
 244 static struct flex_array *alloc_buckets(unsigned int n_buckets)
 245 {
 246         struct flex_array *buckets;
 247         int i, err;
 248
 249         buckets = flex_array_alloc(sizeof(struct hlist_head *),
 250                                    n_buckets, GFP_KERNEL);
 251         if (!buckets)
 252                 return NULL;
 253
 254         err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
 255         if (err) {
 256                 flex_array_free(buckets);
 257                 return NULL;
 258         }
 259
 260         for (i = 0; i < n_buckets; i++)
 261                 INIT_HLIST_HEAD((struct hlist_head *)
 262                                         flex_array_get(buckets, i));
 263
 264         return buckets;
 265 }
 266
 267 static void free_buckets(struct flex_array *buckets)
 268 {
 269         flex_array_free(buckets);
 270 }
 271
 272 struct flow_table *ovs_flow_tbl_alloc(int new_size)
 273 {
 274         struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
 275
 276         if (!table)
 277                 return NULL;
 278
 279         table->buckets = alloc_buckets(new_size);
 280
 281         if (!table->buckets) {
 282                 kfree(table);
 283                 return NULL;
 284         }
 285         table->n_buckets = new_size;
 286         table->count = 0;
 287         table->node_ver = 0;
 288         table->keep_flows = false;
 289         get_random_bytes(&table->hash_seed, sizeof(u32));
 290
 291         return table;
 292 }
 293
 294 static void flow_free(struct sw_flow *flow)
 295 {
 296         flow->dead = true;
 297         ovs_flow_put(flow);
 298 }
 299
 300 void ovs_flow_tbl_destroy(struct flow_table *table)
 301 {
 302         int i;
 303
 304         if (!table)
 305                 return;
 306
 307         if (table->keep_flows)
 308                 goto skip_flows;
 309
 310         for (i = 0; i < table->n_buckets; i++) {
 311                 struct sw_flow *flow;
 312                 struct hlist_head *head = flex_array_get(table->buckets, i);
 313                 struct hlist_node *node, *n;
 314                 int ver = table->node_ver;
 315
 316                 hlist_for_each_entry_safe(flow, node, n, head, hash_node[ver]) {
 317                         hlist_del_rcu(&flow->hash_node[ver]);
 318                         flow_free(flow);
 319                 }
 320         }
 321
 322 skip_flows:
 323         free_buckets(table->buckets);
 324         kfree(table);
 325 }
 326
 327 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
 328 {
 329         struct flow_table *table = container_of(rcu, struct flow_table, rcu);
 330
 331         ovs_flow_tbl_destroy(table);
 332 }
 333
 334 void ovs_flow_tbl_deferred_destroy(struct flow_table *table)
 335 {
 336         if (!table)
 337                 return;
 338
 339         call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
 340 }
 341
 342 struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
 343 {
 344         struct sw_flow *flow;
 345         struct hlist_head *head;
 346         struct hlist_node *n;
 347         int ver;
 348         int i;
 349
 350         ver = table->node_ver;
 351         while (*bucket < table->n_buckets) {
 352                 i = 0;
 353                 head = flex_array_get(table->buckets, *bucket);
 354                 hlist_for_each_entry_rcu(flow, n, head, hash_node[ver]) {
 355                         if (i < *last) {
 356                                 i++;
 357                                 continue;
 358                         }
 359                         *last = i + 1;
 360                         return flow;
 361                 }
 362                 (*bucket)++;
 363                 *last = 0;
 364         }
 365
 366         return NULL;
 367 }
 368
 369 static void flow_table_copy_flows(struct flow_table *old, struct flow_table *new)
 370 {
 371         int old_ver;
 372         int i;
 373
 374         old_ver = old->node_ver;
 375         new->node_ver = !old_ver;
 376
 377         /* Insert in new table. */
 378         for (i = 0; i < old->n_buckets; i++) {
 379                 struct sw_flow *flow;
 380                 struct hlist_head *head;
 381                 struct hlist_node *n;
 382
 383                 head = flex_array_get(old->buckets, i);
 384
 385                 hlist_for_each_entry(flow, n, head, hash_node[old_ver])
 386                         ovs_flow_tbl_insert(new, flow);
 387         }
 388         old->keep_flows = true;
 389 }
 390
 391 static struct flow_table *__flow_tbl_rehash(struct flow_table *table, int n_buckets)
 392 {
 393         struct flow_table *new_table;
 394
 395         new_table = ovs_flow_tbl_alloc(n_buckets);
 396         if (!new_table)
 397                 return ERR_PTR(-ENOMEM);
 398
 399         flow_table_copy_flows(table, new_table);
 400
 401         return new_table;
 402 }
 403
 404 struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table)
 405 {
 406         return __flow_tbl_rehash(table, table->n_buckets);
 407 }
 408
 409 struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
 410 {
 411         return __flow_tbl_rehash(table, table->n_buckets * 2);
 412 }
 413
 414 /* RCU callback used by ovs_flow_deferred_free. */
 415 static void rcu_free_flow_callback(struct rcu_head *rcu)
 416 {
 417         struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
 418
 419         flow->dead = true;
 420         ovs_flow_put(flow);
 421 }
 422
 423 /* Schedules 'flow' to be freed after the next RCU grace period.
 424  * The caller must hold rcu_read_lock for this to be sensible. */
 425 void ovs_flow_deferred_free(struct sw_flow *flow)
 426 {
 427         call_rcu(&flow->rcu, rcu_free_flow_callback);
 428 }
 429
 430 void ovs_flow_hold(struct sw_flow *flow)
 431 {
 432         atomic_inc(&flow->refcnt);
 433 }
 434
 435 void ovs_flow_put(struct sw_flow *flow)
 436 {
 437         if (unlikely(!flow))
 438                 return;
 439
 440         if (atomic_dec_and_test(&flow->refcnt)) {
 441                 kfree((struct sf_flow_acts __force *)flow->sf_acts);
 442                 kmem_cache_free(flow_cache, flow);
 443         }
 444 }
 445
 446 /* RCU callback used by ovs_flow_deferred_free_acts. */
 447 static void rcu_free_acts_callback(struct rcu_head *rcu)
 448 {
 449         struct sw_flow_actions *sf_acts = container_of(rcu,
 450                         struct sw_flow_actions, rcu);
 451         kfree(sf_acts);
 452 }
 453
 454 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
 455  * The caller must hold rcu_read_lock for this to be sensible. */
 456 void ovs_flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
 457 {
 458         call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
 459 }
 460
 461 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 462 {
 463         struct qtag_prefix {
 464                 __be16 eth_type; /* ETH_P_8021Q */
 465                 __be16 tci;
 466         };
 467         struct qtag_prefix *qp;
 468
 469         if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
 470                 return 0;
 471
 472         if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
 473                                          sizeof(__be16))))
 474                 return -ENOMEM;
 475
 476         qp = (struct qtag_prefix *) skb->data;
 477         key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
 478         __skb_pull(skb, sizeof(struct qtag_prefix));
 479
 480         return 0;
 481 }
 482
 483 static __be16 parse_ethertype(struct sk_buff *skb)
 484 {
 485         struct llc_snap_hdr {
 486                 u8  dsap;  /* Always 0xAA */
 487                 u8  ssap;  /* Always 0xAA */
 488                 u8  ctrl;
 489                 u8  oui[3];
 490                 __be16 ethertype;
 491         };
 492         struct llc_snap_hdr *llc;
 493         __be16 proto;
 494
 495         proto = *(__be16 *) skb->data;
 496         __skb_pull(skb, sizeof(__be16));
 497
 498         if (ntohs(proto) >= 1536)
 499                 return proto;
 500
 501         if (skb->len < sizeof(struct llc_snap_hdr))
 502                 return htons(ETH_P_802_2);
 503
 504         if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
 505                 return htons(0);
 506
 507         llc = (struct llc_snap_hdr *) skb->data;
 508         if (llc->dsap != LLC_SAP_SNAP ||
 509             llc->ssap != LLC_SAP_SNAP ||
 510             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
 511                 return htons(ETH_P_802_2);
 512
 513         __skb_pull(skb, sizeof(struct llc_snap_hdr));
 514         return llc->ethertype;
 515 }
 516
 517 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
 518                         int *key_lenp, int nh_len)
 519 {
 520         struct icmp6hdr *icmp = icmp6_hdr(skb);
 521         int error = 0;
 522         int key_len;
 523
 524         /* The ICMPv6 type and code fields use the 16-bit transport port
 525          * fields, so we need to store them in 16-bit network byte order.
 526          */
 527         key->ipv6.tp.src = htons(icmp->icmp6_type);
 528         key->ipv6.tp.dst = htons(icmp->icmp6_code);
 529         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 530
 531         if (icmp->icmp6_code == 0 &&
 532             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
 533              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 534                 int icmp_len = skb->len - skb_transport_offset(skb);
 535                 struct nd_msg *nd;
 536                 int offset;
 537
 538                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 539
 540                 /* In order to process neighbor discovery options, we need the
 541                  * entire packet.
 542                  */
 543                 if (unlikely(icmp_len < sizeof(*nd)))
 544                         goto out;
 545                 if (unlikely(skb_linearize(skb))) {
 546                         error = -ENOMEM;
 547                         goto out;
 548                 }
 549
 550                 nd = (struct nd_msg *)skb_transport_header(skb);
 551                 key->ipv6.nd.target = nd->target;
 552                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 553
 554                 icmp_len -= sizeof(*nd);
 555                 offset = 0;
 556                 while (icmp_len >= 8) {
 557                         struct nd_opt_hdr *nd_opt =
 558                                  (struct nd_opt_hdr *)(nd->opt + offset);
 559                         int opt_len = nd_opt->nd_opt_len * 8;
 560
 561                         if (unlikely(!opt_len || opt_len > icmp_len))
 562                                 goto invalid;
 563
 564                         /* Store the link layer address if the appropriate
 565                          * option is provided.  It is considered an error if
 566                          * the same link layer option is specified twice.
 567                          */
 568                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
 569                             && opt_len == 8) {
 570                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
 571                                         goto invalid;
 572                                 memcpy(key->ipv6.nd.sll,
 573                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 574                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
 575                                    && opt_len == 8) {
 576                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
 577                                         goto invalid;
 578                                 memcpy(key->ipv6.nd.tll,
 579                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 580                         }
 581
 582                         icmp_len -= opt_len;
 583                         offset += opt_len;
 584                 }
 585         }
 586
 587         goto out;
 588
 589 invalid:
 590         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
 591         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
 592         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
 593
 594 out:
 595         *key_lenp = key_len;
 596         return error;
 597 }
 598
 599 /**
 600  * ovs_flow_extract - extracts a flow key from an Ethernet frame.
 601  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 602  * Ethernet header
 603  * @in_port: port number on which @skb was received.
 604  * @key: output flow key
 605  * @key_lenp: length of output flow key
 606  *
 607  * The caller must ensure that skb->len >= ETH_HLEN.
 608  *
 609  * Returns 0 if successful, otherwise a negative errno value.
 610  *
 611  * Initializes @skb header pointers as follows:
 612  *
 613  *    - skb->mac_header: the Ethernet header.
 614  *
 615  *    - skb->network_header: just past the Ethernet header, or just past the
 616  *      VLAN header, to the first byte of the Ethernet payload.
 617  *
 618  *    - skb->transport_header: If key->dl_type is ETH_P_IP or ETH_P_IPV6
 619  *      on output, then just past the IP header, if one is present and
 620  *      of a correct length, otherwise the same as skb->network_header.
 621  *      For other key->dl_type values it is left untouched.
 622  */
 623 int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
 624                  int *key_lenp)
 625 {
 626         int error = 0;
 627         int key_len = SW_FLOW_KEY_OFFSET(eth);
 628         struct ethhdr *eth;
 629
 630         memset(key, 0, sizeof(*key));
 631
 632         key->phy.priority = skb->priority;
 633         key->phy.tun_id = OVS_CB(skb)->tun_id;
 634         key->phy.in_port = in_port;
 635
 636         skb_reset_mac_header(skb);
 637
 638         /* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
 639          * header in the linear data area.
 640          */
 641         eth = eth_hdr(skb);
 642         memcpy(key->eth.src, eth->h_source, ETH_ALEN);
 643         memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
 644
 645         __skb_pull(skb, 2 * ETH_ALEN);
 646
 647         if (vlan_tx_tag_present(skb))
 648                 key->eth.tci = htons(vlan_get_tci(skb));
 649         else if (eth->h_proto == htons(ETH_P_8021Q))
 650                 if (unlikely(parse_vlan(skb, key)))
 651                         return -ENOMEM;
 652
 653         key->eth.type = parse_ethertype(skb);
 654         if (unlikely(key->eth.type == htons(0)))
 655                 return -ENOMEM;
 656
 657         skb_reset_network_header(skb);
 658         __skb_push(skb, skb->data - skb_mac_header(skb));
 659
 660         /* Network layer. */
 661         if (key->eth.type == htons(ETH_P_IP)) {
 662                 struct iphdr *nh;
 663                 __be16 offset;
 664
 665                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
 666
 667                 error = check_iphdr(skb);
 668                 if (unlikely(error)) {
 669                         if (error == -EINVAL) {
 670                                 skb->transport_header = skb->network_header;
 671                                 error = 0;
 672                         }
 673                         goto out;
 674                 }
 675
 676                 nh = ip_hdr(skb);
 677                 key->ipv4.addr.src = nh->saddr;
 678                 key->ipv4.addr.dst = nh->daddr;
 679
 680                 key->ip.proto = nh->protocol;
 681                 key->ip.tos = nh->tos;
 682                 key->ip.ttl = nh->ttl;
 683
 684                 offset = nh->frag_off & htons(IP_OFFSET);
 685                 if (offset) {
 686                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 687                         goto out;
 688                 }
 689                 if (nh->frag_off & htons(IP_MF) ||
 690                          skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 691                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 692
 693                 /* Transport layer. */
 694                 if (key->ip.proto == IPPROTO_TCP) {
 695                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 696                         if (tcphdr_ok(skb)) {
 697                                 struct tcphdr *tcp = tcp_hdr(skb);
 698                                 key->ipv4.tp.src = tcp->source;
 699                                 key->ipv4.tp.dst = tcp->dest;
 700                         }
 701                 } else if (key->ip.proto == IPPROTO_UDP) {
 702                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 703                         if (udphdr_ok(skb)) {
 704                                 struct udphdr *udp = udp_hdr(skb);
 705                                 key->ipv4.tp.src = udp->source;
 706                                 key->ipv4.tp.dst = udp->dest;
 707                         }
 708                 } else if (key->ip.proto == IPPROTO_ICMP) {
 709                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 710                         if (icmphdr_ok(skb)) {
 711                                 struct icmphdr *icmp = icmp_hdr(skb);
 712                                 /* The ICMP type and code fields use the 16-bit
 713                                  * transport port fields, so we need to store
 714                                  * them in 16-bit network byte order. */
 715                                 key->ipv4.tp.src = htons(icmp->type);
 716                                 key->ipv4.tp.dst = htons(icmp->code);
 717                         }
 718                 }
 719
 720         } else if (key->eth.type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
 721                 struct arp_eth_header *arp;
 722
 723                 arp = (struct arp_eth_header *)skb_network_header(skb);
 724
 725                 if (arp->ar_hrd == htons(ARPHRD_ETHER)
 726                                 && arp->ar_pro == htons(ETH_P_IP)
 727                                 && arp->ar_hln == ETH_ALEN
 728                                 && arp->ar_pln == 4) {
 729
 730                         /* We only match on the lower 8 bits of the opcode. */
 731                         if (ntohs(arp->ar_op) <= 0xff)
 732                                 key->ip.proto = ntohs(arp->ar_op);
 733
 734                         if (key->ip.proto == ARPOP_REQUEST
 735                                         || key->ip.proto == ARPOP_REPLY) {
 736                                 memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
 737                                 memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
 738                                 memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
 739                                 memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
 740                                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
 741                         }
 742                 }
 743         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 744                 int nh_len;             /* IPv6 Header + Extensions */
 745
 746                 nh_len = parse_ipv6hdr(skb, key, &key_len);
 747                 if (unlikely(nh_len < 0)) {
 748                         if (nh_len == -EINVAL)
 749                                 skb->transport_header = skb->network_header;
 750                         else
 751                                 error = nh_len;
 752                         goto out;
 753                 }
 754
 755                 if (key->ip.frag == OVS_FRAG_TYPE_LATER)
 756                         goto out;
 757                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 758                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 759
 760                 /* Transport layer. */
 761                 if (key->ip.proto == NEXTHDR_TCP) {
 762                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 763                         if (tcphdr_ok(skb)) {
 764                                 struct tcphdr *tcp = tcp_hdr(skb);
 765                                 key->ipv6.tp.src = tcp->source;
 766                                 key->ipv6.tp.dst = tcp->dest;
 767                         }
 768                 } else if (key->ip.proto == NEXTHDR_UDP) {
 769                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 770                         if (udphdr_ok(skb)) {
 771                                 struct udphdr *udp = udp_hdr(skb);
 772                                 key->ipv6.tp.src = udp->source;
 773                                 key->ipv6.tp.dst = udp->dest;
 774                         }
 775                 } else if (key->ip.proto == NEXTHDR_ICMP) {
 776                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 777                         if (icmp6hdr_ok(skb)) {
 778                                 error = parse_icmpv6(skb, key, &key_len, nh_len);
 779                                 if (error < 0)
 780                                         goto out;
 781                         }
 782                 }
 783         }
 784
 785 out:
 786         *key_lenp = key_len;
 787         return error;
 788 }
 789
 790 u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len)
 791 {
 792         return jhash2((u32 *)key, DIV_ROUND_UP(key_len, sizeof(u32)), 0);
 793 }
 794
 795 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
 796                                 struct sw_flow_key *key, int key_len)
 797 {
 798         struct sw_flow *flow;
 799         struct hlist_node *n;
 800         struct hlist_head *head;
 801         u32 hash;
 802
 803         hash = ovs_flow_hash(key, key_len);
 804
 805         head = find_bucket(table, hash);
 806         hlist_for_each_entry_rcu(flow, n, head, hash_node[table->node_ver]) {
 807
 808                 if (flow->hash == hash &&
 809                     !memcmp(&flow->key, key, key_len)) {
 810                         return flow;
 811                 }
 812         }
 813         return NULL;
 814 }
 815
 816 void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
 817 {
 818         struct hlist_head *head;
 819
 820         head = find_bucket(table, flow->hash);
 821         hlist_add_head_rcu(&flow->hash_node[table->node_ver], head);
 822         table->count++;
 823 }
 824
 825 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
 826 {
 827         hlist_del_rcu(&flow->hash_node[table->node_ver]);
 828         table->count--;
 829         BUG_ON(table->count < 0);
 830 }
 831
 832 /* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
 833 const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
 834         [OVS_KEY_ATTR_ENCAP] = -1,
 835         [OVS_KEY_ATTR_PRIORITY] = sizeof(u32),
 836         [OVS_KEY_ATTR_IN_PORT] = sizeof(u32),
 837         [OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
 838         [OVS_KEY_ATTR_VLAN] = sizeof(__be16),
 839         [OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
 840         [OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
 841         [OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
 842         [OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
 843         [OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
 844         [OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
 845         [OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
 846         [OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
 847         [OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
 848
 849         /* Not upstream. */
 850         [OVS_KEY_ATTR_TUN_ID] = sizeof(__be64),
 851 };
 852
 853 static int ipv4_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 854                                   const struct nlattr *a[], u64 *attrs)
 855 {
 856         const struct ovs_key_icmp *icmp_key;
 857         const struct ovs_key_tcp *tcp_key;
 858         const struct ovs_key_udp *udp_key;
 859
 860         switch (swkey->ip.proto) {
 861         case IPPROTO_TCP:
 862                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 863                         return -EINVAL;
 864                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 865
 866                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 867                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 868                 swkey->ipv4.tp.src = tcp_key->tcp_src;
 869                 swkey->ipv4.tp.dst = tcp_key->tcp_dst;
 870                 break;
 871
 872         case IPPROTO_UDP:
 873                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 874                         return -EINVAL;
 875                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 876
 877                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 878                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 879                 swkey->ipv4.tp.src = udp_key->udp_src;
 880                 swkey->ipv4.tp.dst = udp_key->udp_dst;
 881                 break;
 882
 883         case IPPROTO_ICMP:
 884                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMP)))
 885                         return -EINVAL;
 886                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
 887
 888                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 889                 icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
 890                 swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
 891                 swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
 892                 break;
 893         }
 894
 895         return 0;
 896 }
 897
 898 static int ipv6_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 899                                   const struct nlattr *a[], u64 *attrs)
 900 {
 901         const struct ovs_key_icmpv6 *icmpv6_key;
 902         const struct ovs_key_tcp *tcp_key;
 903         const struct ovs_key_udp *udp_key;
 904
 905         switch (swkey->ip.proto) {
 906         case IPPROTO_TCP:
 907                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 908                         return -EINVAL;
 909                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 910
 911                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 912                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 913                 swkey->ipv6.tp.src = tcp_key->tcp_src;
 914                 swkey->ipv6.tp.dst = tcp_key->tcp_dst;
 915                 break;
 916
 917         case IPPROTO_UDP:
 918                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 919                         return -EINVAL;
 920                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 921
 922                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 923                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 924                 swkey->ipv6.tp.src = udp_key->udp_src;
 925                 swkey->ipv6.tp.dst = udp_key->udp_dst;
 926                 break;
 927
 928         case IPPROTO_ICMPV6:
 929                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMPV6)))
 930                         return -EINVAL;
 931                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
 932
 933                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 934                 icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
 935                 swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
 936                 swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
 937
 938                 if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
 939                     swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 940                         const struct ovs_key_nd *nd_key;
 941
 942                         if (!(*attrs & (1 << OVS_KEY_ATTR_ND)))
 943                                 return -EINVAL;
 944                         *attrs &= ~(1 << OVS_KEY_ATTR_ND);
 945
 946                         *key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 947                         nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
 948                         memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
 949                                sizeof(swkey->ipv6.nd.target));
 950                         memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
 951                         memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
 952                 }
 953                 break;
 954         }
 955
 956         return 0;
 957 }
 958
 959 static int parse_flow_nlattrs(const struct nlattr *attr,
 960                               const struct nlattr *a[], u64 *attrsp)
 961 {
 962         const struct nlattr *nla;
 963         u64 attrs;
 964         int rem;
 965
 966         attrs = 0;
 967         nla_for_each_nested(nla, attr, rem) {
 968                 u16 type = nla_type(nla);
 969                 int expected_len;
 970
 971                 if (type > OVS_KEY_ATTR_MAX || attrs & (1ULL << type))
 972                         return -EINVAL;
 973
 974                 expected_len = ovs_key_lens[type];
 975                 if (nla_len(nla) != expected_len && expected_len != -1)
 976                         return -EINVAL;
 977
 978                 attrs |= 1ULL << type;
 979                 a[type] = nla;
 980         }
 981         if (rem)
 982                 return -EINVAL;
 983
 984         *attrsp = attrs;
 985         return 0;
 986 }
 987
 988 /**
 989  * ovs_flow_from_nlattrs - parses Netlink attributes into a flow key.
 990  * @swkey: receives the extracted flow key.
 991  * @key_lenp: number of bytes used in @swkey.
 992  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
 993  * sequence.
 994  */
 995 int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
 996                       const struct nlattr *attr)
 997 {
 998         const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
 999         const struct ovs_key_ethernet *eth_key;
1000         int key_len;
1001         u64 attrs;
1002         int err;
1003
1004         memset(swkey, 0, sizeof(struct sw_flow_key));
1005         key_len = SW_FLOW_KEY_OFFSET(eth);
1006
1007         err = parse_flow_nlattrs(attr, a, &attrs);
1008         if (err)
1009                 return err;
1010
1011         /* Metadata attributes. */
1012         if (attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
1013                 swkey->phy.priority = nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]);
1014                 attrs &= ~(1 << OVS_KEY_ATTR_PRIORITY);
1015         }
1016         if (attrs & (1 << OVS_KEY_ATTR_IN_PORT)) {
1017                 u32 in_port = nla_get_u32(a[OVS_KEY_ATTR_IN_PORT]);
1018                 if (in_port >= DP_MAX_PORTS)
1019                         return -EINVAL;
1020                 swkey->phy.in_port = in_port;
1021                 attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
1022         } else {
1023                 swkey->phy.in_port = USHRT_MAX;
1024         }
1025
1026         if (attrs & (1ULL << OVS_KEY_ATTR_TUN_ID)) {
1027                 swkey->phy.tun_id = nla_get_be64(a[OVS_KEY_ATTR_TUN_ID]);
1028                 attrs &= ~(1ULL << OVS_KEY_ATTR_TUN_ID);
1029         }
1030
1031         /* Data attributes. */
1032         if (!(attrs & (1 << OVS_KEY_ATTR_ETHERNET)))
1033                 return -EINVAL;
1034         attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
1035
1036         eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
1037         memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
1038         memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
1039
1040         if (attrs & (1u << OVS_KEY_ATTR_ETHERTYPE) &&
1041             nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q)) {
1042                 const struct nlattr *encap;
1043                 __be16 tci;
1044
1045                 if (attrs != ((1 << OVS_KEY_ATTR_VLAN) |
1046                               (1 << OVS_KEY_ATTR_ETHERTYPE) |
1047                               (1 << OVS_KEY_ATTR_ENCAP)))
1048                         return -EINVAL;
1049
1050                 encap = a[OVS_KEY_ATTR_ENCAP];
1051                 tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
1052                 if (tci & htons(VLAN_TAG_PRESENT)) {
1053                         swkey->eth.tci = tci;
1054
1055                         err = parse_flow_nlattrs(encap, a, &attrs);
1056                         if (err)
1057                                 return err;
1058                 } else if (!tci) {
1059                         /* Corner case for truncated 802.1Q header. */
1060                         if (nla_len(encap))
1061                                 return -EINVAL;
1062
1063                         swkey->eth.type = htons(ETH_P_8021Q);
1064                         *key_lenp = key_len;
1065                         return 0;
1066                 } else {
1067                         return -EINVAL;
1068                 }
1069         }
1070
1071         if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
1072                 swkey->eth.type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
1073                 if (ntohs(swkey->eth.type) < 1536)
1074                         return -EINVAL;
1075                 attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
1076         } else {
1077                 swkey->eth.type = htons(ETH_P_802_2);
1078         }
1079
1080         if (swkey->eth.type == htons(ETH_P_IP)) {
1081                 const struct ovs_key_ipv4 *ipv4_key;
1082
1083                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV4)))
1084                         return -EINVAL;
1085                 attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
1086
1087                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
1088                 ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
1089                 if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
1090                         return -EINVAL;
1091                 swkey->ip.proto = ipv4_key->ipv4_proto;
1092                 swkey->ip.tos = ipv4_key->ipv4_tos;
1093                 swkey->ip.ttl = ipv4_key->ipv4_ttl;
1094                 swkey->ip.frag = ipv4_key->ipv4_frag;
1095                 swkey->ipv4.addr.src = ipv4_key->ipv4_src;
1096                 swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
1097
1098                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1099                         err = ipv4_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1100                         if (err)
1101                                 return err;
1102                 }
1103         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1104                 const struct ovs_key_ipv6 *ipv6_key;
1105
1106                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV6)))
1107                         return -EINVAL;
1108                 attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
1109
1110                 key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
1111                 ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
1112                 if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
1113                         return -EINVAL;
1114                 swkey->ipv6.label = ipv6_key->ipv6_label;
1115                 swkey->ip.proto = ipv6_key->ipv6_proto;
1116                 swkey->ip.tos = ipv6_key->ipv6_tclass;
1117                 swkey->ip.ttl = ipv6_key->ipv6_hlimit;
1118                 swkey->ip.frag = ipv6_key->ipv6_frag;
1119                 memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
1120                        sizeof(swkey->ipv6.addr.src));
1121                 memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
1122                        sizeof(swkey->ipv6.addr.dst));
1123
1124                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1125                         err = ipv6_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1126                         if (err)
1127                                 return err;
1128                 }
1129         } else if (swkey->eth.type == htons(ETH_P_ARP)) {
1130                 const struct ovs_key_arp *arp_key;
1131
1132                 if (!(attrs & (1 << OVS_KEY_ATTR_ARP)))
1133                         return -EINVAL;
1134                 attrs &= ~(1 << OVS_KEY_ATTR_ARP);
1135
1136                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
1137                 arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
1138                 swkey->ipv4.addr.src = arp_key->arp_sip;
1139                 swkey->ipv4.addr.dst = arp_key->arp_tip;
1140                 if (arp_key->arp_op & htons(0xff00))
1141                         return -EINVAL;
1142                 swkey->ip.proto = ntohs(arp_key->arp_op);
1143                 memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
1144                 memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
1145         }
1146
1147         if (attrs)
1148                 return -EINVAL;
1149         *key_lenp = key_len;
1150
1151         return 0;
1152 }
1153
1154 /**
1155  * ovs_flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
1156  * @in_port: receives the extracted input port.
1157  * @tun_id: receives the extracted tunnel ID.
1158  * @key: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1159  * sequence.
1160  *
1161  * This parses a series of Netlink attributes that form a flow key, which must
1162  * take the same form accepted by flow_from_nlattrs(), but only enough of it to
1163  * get the metadata, that is, the parts of the flow key that cannot be
1164  * extracted from the packet itself.
1165  */
1166 int ovs_flow_metadata_from_nlattrs(u32 *priority, u16 *in_port, __be64 *tun_id,
1167                                    const struct nlattr *attr)
1168 {
1169         const struct nlattr *nla;
1170         int rem;
1171
1172         *in_port = USHRT_MAX;
1173         *tun_id = 0;
1174         *priority = 0;
1175
1176         nla_for_each_nested(nla, attr, rem) {
1177                 int type = nla_type(nla);
1178
1179                 if (type <= OVS_KEY_ATTR_MAX && ovs_key_lens[type] > 0) {
1180                         if (nla_len(nla) != ovs_key_lens[type])
1181                                 return -EINVAL;
1182
1183                         switch (type) {
1184                         case OVS_KEY_ATTR_PRIORITY:
1185                                 *priority = nla_get_u32(nla);
1186                                 break;
1187
1188                         case OVS_KEY_ATTR_TUN_ID:
1189                                 *tun_id = nla_get_be64(nla);
1190                                 break;
1191
1192                         case OVS_KEY_ATTR_IN_PORT:
1193                                 if (nla_get_u32(nla) >= DP_MAX_PORTS)
1194                                         return -EINVAL;
1195                                 *in_port = nla_get_u32(nla);
1196                                 break;
1197                         }
1198                 }
1199         }
1200         if (rem)
1201                 return -EINVAL;
1202         return 0;
1203 }
1204
1205 int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
1206 {
1207         struct ovs_key_ethernet *eth_key;
1208         struct nlattr *nla, *encap;
1209
1210         if (swkey->phy.priority)
1211                 NLA_PUT_U32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority);
1212
1213         if (swkey->phy.tun_id != cpu_to_be64(0))
1214                 NLA_PUT_BE64(skb, OVS_KEY_ATTR_TUN_ID, swkey->phy.tun_id);
1215
1216         if (swkey->phy.in_port != USHRT_MAX)
1217                 NLA_PUT_U32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port);
1218
1219         nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
1220         if (!nla)
1221                 goto nla_put_failure;
1222         eth_key = nla_data(nla);
1223         memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
1224         memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
1225
1226         if (swkey->eth.tci || swkey->eth.type == htons(ETH_P_8021Q)) {
1227                 NLA_PUT_BE16(skb, OVS_KEY_ATTR_ETHERTYPE, htons(ETH_P_8021Q));
1228                 NLA_PUT_BE16(skb, OVS_KEY_ATTR_VLAN, swkey->eth.tci);
1229                 encap = nla_nest_start(skb, OVS_KEY_ATTR_ENCAP);
1230                 if (!swkey->eth.tci)
1231                         goto unencap;
1232         } else {
1233                 encap = NULL;
1234         }
1235
1236         if (swkey->eth.type == htons(ETH_P_802_2))
1237                 goto unencap;
1238
1239         NLA_PUT_BE16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type);
1240
1241         if (swkey->eth.type == htons(ETH_P_IP)) {
1242                 struct ovs_key_ipv4 *ipv4_key;
1243
1244                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
1245                 if (!nla)
1246                         goto nla_put_failure;
1247                 ipv4_key = nla_data(nla);
1248                 ipv4_key->ipv4_src = swkey->ipv4.addr.src;
1249                 ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
1250                 ipv4_key->ipv4_proto = swkey->ip.proto;
1251                 ipv4_key->ipv4_tos = swkey->ip.tos;
1252                 ipv4_key->ipv4_ttl = swkey->ip.ttl;
1253                 ipv4_key->ipv4_frag = swkey->ip.frag;
1254         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1255                 struct ovs_key_ipv6 *ipv6_key;
1256
1257                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
1258                 if (!nla)
1259                         goto nla_put_failure;
1260                 ipv6_key = nla_data(nla);
1261                 memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
1262                                 sizeof(ipv6_key->ipv6_src));
1263                 memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
1264                                 sizeof(ipv6_key->ipv6_dst));
1265                 ipv6_key->ipv6_label = swkey->ipv6.label;
1266                 ipv6_key->ipv6_proto = swkey->ip.proto;
1267                 ipv6_key->ipv6_tclass = swkey->ip.tos;
1268                 ipv6_key->ipv6_hlimit = swkey->ip.ttl;
1269                 ipv6_key->ipv6_frag = swkey->ip.frag;
1270         } else if (swkey->eth.type == htons(ETH_P_ARP)) {
1271                 struct ovs_key_arp *arp_key;
1272
1273                 nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
1274                 if (!nla)
1275                         goto nla_put_failure;
1276                 arp_key = nla_data(nla);
1277                 memset(arp_key, 0, sizeof(struct ovs_key_arp));
1278                 arp_key->arp_sip = swkey->ipv4.addr.src;
1279                 arp_key->arp_tip = swkey->ipv4.addr.dst;
1280                 arp_key->arp_op = htons(swkey->ip.proto);
1281                 memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1282                 memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1283         }
1284
1285         if ((swkey->eth.type == htons(ETH_P_IP) ||
1286              swkey->eth.type == htons(ETH_P_IPV6)) &&
1287              swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1288
1289                 if (swkey->ip.proto == IPPROTO_TCP) {
1290                         struct ovs_key_tcp *tcp_key;
1291
1292                         nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
1293                         if (!nla)
1294                                 goto nla_put_failure;
1295                         tcp_key = nla_data(nla);
1296                         if (swkey->eth.type == htons(ETH_P_IP)) {
1297                                 tcp_key->tcp_src = swkey->ipv4.tp.src;
1298                                 tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1299                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1300                                 tcp_key->tcp_src = swkey->ipv6.tp.src;
1301                                 tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1302                         }
1303                 } else if (swkey->ip.proto == IPPROTO_UDP) {
1304                         struct ovs_key_udp *udp_key;
1305
1306                         nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
1307                         if (!nla)
1308                                 goto nla_put_failure;
1309                         udp_key = nla_data(nla);
1310                         if (swkey->eth.type == htons(ETH_P_IP)) {
1311                                 udp_key->udp_src = swkey->ipv4.tp.src;
1312                                 udp_key->udp_dst = swkey->ipv4.tp.dst;
1313                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1314                                 udp_key->udp_src = swkey->ipv6.tp.src;
1315                                 udp_key->udp_dst = swkey->ipv6.tp.dst;
1316                         }
1317                 } else if (swkey->eth.type == htons(ETH_P_IP) &&
1318                            swkey->ip.proto == IPPROTO_ICMP) {
1319                         struct ovs_key_icmp *icmp_key;
1320
1321                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
1322                         if (!nla)
1323                                 goto nla_put_failure;
1324                         icmp_key = nla_data(nla);
1325                         icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1326                         icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1327                 } else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1328                            swkey->ip.proto == IPPROTO_ICMPV6) {
1329                         struct ovs_key_icmpv6 *icmpv6_key;
1330
1331                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
1332                                                 sizeof(*icmpv6_key));
1333                         if (!nla)
1334                                 goto nla_put_failure;
1335                         icmpv6_key = nla_data(nla);
1336                         icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1337                         icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1338
1339                         if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1340                             icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1341                                 struct ovs_key_nd *nd_key;
1342
1343                                 nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
1344                                 if (!nla)
1345                                         goto nla_put_failure;
1346                                 nd_key = nla_data(nla);
1347                                 memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1348                                                         sizeof(nd_key->nd_target));
1349                                 memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1350                                 memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1351                         }
1352                 }
1353         }
1354
1355 unencap:
1356         if (encap)
1357                 nla_nest_end(skb, encap);
1358
1359         return 0;
1360
1361 nla_put_failure:
1362         return -EMSGSIZE;
1363 }
1364
1365 /* Initializes the flow module.
1366  * Returns zero if successful or a negative error code. */
1367 int ovs_flow_init(void)
1368 {
1369         flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1370                                         0, NULL);
1371         if (flow_cache == NULL)
1372                 return -ENOMEM;
1373
1374         return 0;
1375 }
1376
1377 /* Uninitializes the flow module. */
1378 void ovs_flow_exit(void)
1379 {
1380         kmem_cache_destroy(flow_cache);
1381 }