datapath/flow.c

   1 /*
   2  * Copyright (c) 2007-2011 Nicira, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of version 2 of the GNU General Public
   6  * License as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16  * 02110-1301, USA
  17  */
  18
  19 #include "flow.h"
  20 #include "datapath.h"
  21 #include <linux/uaccess.h>
  22 #include <linux/netdevice.h>
  23 #include <linux/etherdevice.h>
  24 #include <linux/if_ether.h>
  25 #include <linux/if_vlan.h>
  26 #include <net/llc_pdu.h>
  27 #include <linux/kernel.h>
  28 #include <linux/jhash.h>
  29 #include <linux/jiffies.h>
  30 #include <linux/llc.h>
  31 #include <linux/module.h>
  32 #include <linux/in.h>
  33 #include <linux/rcupdate.h>
  34 #include <linux/if_arp.h>
  35 #include <linux/ip.h>
  36 #include <linux/ipv6.h>
  37 #include <linux/tcp.h>
  38 #include <linux/udp.h>
  39 #include <linux/icmp.h>
  40 #include <linux/icmpv6.h>
  41 #include <linux/rculist.h>
  42 #include <net/ip.h>
  43 #include <net/ipv6.h>
  44 #include <net/ndisc.h>
  45
  46 #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.eth.type == htons(ETH_P_IPV6)) &&
 189             flow->key.ip.proto == IPPROTO_TCP &&
 190             likely(skb->len >= skb_transport_offset(skb) + sizeof(struct tcphdr))) {
 191                 u8 *tcp = (u8 *)tcp_hdr(skb);
 192                 tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
 193         }
 194
 195         spin_lock(&flow->lock);
 196         flow->used = jiffies;
 197         flow->packet_count++;
 198         flow->byte_count += skb->len;
 199         flow->tcp_flags |= tcp_flags;
 200         spin_unlock(&flow->lock);
 201 }
 202
 203 struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *actions)
 204 {
 205         int actions_len = nla_len(actions);
 206         struct sw_flow_actions *sfa;
 207
 208         if (actions_len > MAX_ACTIONS_BUFSIZE)
 209                 return ERR_PTR(-EINVAL);
 210
 211         sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
 212         if (!sfa)
 213                 return ERR_PTR(-ENOMEM);
 214
 215         sfa->actions_len = actions_len;
 216         memcpy(sfa->actions, nla_data(actions), actions_len);
 217         return sfa;
 218 }
 219
 220 struct sw_flow *ovs_flow_alloc(void)
 221 {
 222         struct sw_flow *flow;
 223
 224         flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
 225         if (!flow)
 226                 return ERR_PTR(-ENOMEM);
 227
 228         spin_lock_init(&flow->lock);
 229         atomic_set(&flow->refcnt, 1);
 230         flow->sf_acts = NULL;
 231         flow->dead = false;
 232
 233         return flow;
 234 }
 235
 236 static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
 237 {
 238         hash = jhash_1word(hash, table->hash_seed);
 239         return flex_array_get(table->buckets,
 240                                 (hash & (table->n_buckets - 1)));
 241 }
 242
 243 static struct flex_array *alloc_buckets(unsigned int n_buckets)
 244 {
 245         struct flex_array *buckets;
 246         int i, err;
 247
 248         buckets = flex_array_alloc(sizeof(struct hlist_head *),
 249                                    n_buckets, GFP_KERNEL);
 250         if (!buckets)
 251                 return NULL;
 252
 253         err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
 254         if (err) {
 255                 flex_array_free(buckets);
 256                 return NULL;
 257         }
 258
 259         for (i = 0; i < n_buckets; i++)
 260                 INIT_HLIST_HEAD((struct hlist_head *)
 261                                         flex_array_get(buckets, i));
 262
 263         return buckets;
 264 }
 265
 266 static void free_buckets(struct flex_array *buckets)
 267 {
 268         flex_array_free(buckets);
 269 }
 270
 271 struct flow_table *ovs_flow_tbl_alloc(int new_size)
 272 {
 273         struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
 274
 275         if (!table)
 276                 return NULL;
 277
 278         table->buckets = alloc_buckets(new_size);
 279
 280         if (!table->buckets) {
 281                 kfree(table);
 282                 return NULL;
 283         }
 284         table->n_buckets = new_size;
 285         table->count = 0;
 286         table->node_ver = 0;
 287         table->keep_flows = false;
 288         get_random_bytes(&table->hash_seed, sizeof(u32));
 289
 290         return table;
 291 }
 292
 293 static void flow_free(struct sw_flow *flow)
 294 {
 295         flow->dead = true;
 296         ovs_flow_put(flow);
 297 }
 298
 299 void ovs_flow_tbl_destroy(struct flow_table *table)
 300 {
 301         int i;
 302
 303         if (!table)
 304                 return;
 305
 306         if (table->keep_flows)
 307                 goto skip_flows;
 308
 309         for (i = 0; i < table->n_buckets; i++) {
 310                 struct sw_flow *flow;
 311                 struct hlist_head *head = flex_array_get(table->buckets, i);
 312                 struct hlist_node *node, *n;
 313                 int ver = table->node_ver;
 314
 315                 hlist_for_each_entry_safe(flow, node, n, head, hash_node[ver]) {
 316                         hlist_del_rcu(&flow->hash_node[ver]);
 317                         flow_free(flow);
 318                 }
 319         }
 320
 321 skip_flows:
 322         free_buckets(table->buckets);
 323         kfree(table);
 324 }
 325
 326 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
 327 {
 328         struct flow_table *table = container_of(rcu, struct flow_table, rcu);
 329
 330         ovs_flow_tbl_destroy(table);
 331 }
 332
 333 void ovs_flow_tbl_deferred_destroy(struct flow_table *table)
 334 {
 335         if (!table)
 336                 return;
 337
 338         call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
 339 }
 340
 341 struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
 342 {
 343         struct sw_flow *flow;
 344         struct hlist_head *head;
 345         struct hlist_node *n;
 346         int ver;
 347         int i;
 348
 349         ver = table->node_ver;
 350         while (*bucket < table->n_buckets) {
 351                 i = 0;
 352                 head = flex_array_get(table->buckets, *bucket);
 353                 hlist_for_each_entry_rcu(flow, n, head, hash_node[ver]) {
 354                         if (i < *last) {
 355                                 i++;
 356                                 continue;
 357                         }
 358                         *last = i + 1;
 359                         return flow;
 360                 }
 361                 (*bucket)++;
 362                 *last = 0;
 363         }
 364
 365         return NULL;
 366 }
 367
 368 static void flow_table_copy_flows(struct flow_table *old, struct flow_table *new)
 369 {
 370         int old_ver;
 371         int i;
 372
 373         old_ver = old->node_ver;
 374         new->node_ver = !old_ver;
 375
 376         /* Insert in new table. */
 377         for (i = 0; i < old->n_buckets; i++) {
 378                 struct sw_flow *flow;
 379                 struct hlist_head *head;
 380                 struct hlist_node *n;
 381
 382                 head = flex_array_get(old->buckets, i);
 383
 384                 hlist_for_each_entry(flow, n, head, hash_node[old_ver])
 385                         ovs_flow_tbl_insert(new, flow);
 386         }
 387         old->keep_flows = true;
 388 }
 389
 390 static struct flow_table *__flow_tbl_rehash(struct flow_table *table, int n_buckets)
 391 {
 392         struct flow_table *new_table;
 393
 394         new_table = ovs_flow_tbl_alloc(n_buckets);
 395         if (!new_table)
 396                 return ERR_PTR(-ENOMEM);
 397
 398         flow_table_copy_flows(table, new_table);
 399
 400         return new_table;
 401 }
 402
 403 struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table)
 404 {
 405         return __flow_tbl_rehash(table, table->n_buckets);
 406 }
 407
 408 struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
 409 {
 410         return __flow_tbl_rehash(table, table->n_buckets * 2);
 411 }
 412
 413 /* RCU callback used by ovs_flow_deferred_free. */
 414 static void rcu_free_flow_callback(struct rcu_head *rcu)
 415 {
 416         struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
 417
 418         flow->dead = true;
 419         ovs_flow_put(flow);
 420 }
 421
 422 /* Schedules 'flow' to be freed after the next RCU grace period.
 423  * The caller must hold rcu_read_lock for this to be sensible. */
 424 void ovs_flow_deferred_free(struct sw_flow *flow)
 425 {
 426         call_rcu(&flow->rcu, rcu_free_flow_callback);
 427 }
 428
 429 void ovs_flow_hold(struct sw_flow *flow)
 430 {
 431         atomic_inc(&flow->refcnt);
 432 }
 433
 434 void ovs_flow_put(struct sw_flow *flow)
 435 {
 436         if (unlikely(!flow))
 437                 return;
 438
 439         if (atomic_dec_and_test(&flow->refcnt)) {
 440                 kfree((struct sf_flow_acts __force *)flow->sf_acts);
 441                 kmem_cache_free(flow_cache, flow);
 442         }
 443 }
 444
 445 /* RCU callback used by ovs_flow_deferred_free_acts. */
 446 static void rcu_free_acts_callback(struct rcu_head *rcu)
 447 {
 448         struct sw_flow_actions *sf_acts = container_of(rcu,
 449                         struct sw_flow_actions, rcu);
 450         kfree(sf_acts);
 451 }
 452
 453 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
 454  * The caller must hold rcu_read_lock for this to be sensible. */
 455 void ovs_flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
 456 {
 457         call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
 458 }
 459
 460 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 461 {
 462         struct qtag_prefix {
 463                 __be16 eth_type; /* ETH_P_8021Q */
 464                 __be16 tci;
 465         };
 466         struct qtag_prefix *qp;
 467
 468         if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
 469                 return 0;
 470
 471         if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
 472                                          sizeof(__be16))))
 473                 return -ENOMEM;
 474
 475         qp = (struct qtag_prefix *) skb->data;
 476         key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
 477         __skb_pull(skb, sizeof(struct qtag_prefix));
 478
 479         return 0;
 480 }
 481
 482 static __be16 parse_ethertype(struct sk_buff *skb)
 483 {
 484         struct llc_snap_hdr {
 485                 u8  dsap;  /* Always 0xAA */
 486                 u8  ssap;  /* Always 0xAA */
 487                 u8  ctrl;
 488                 u8  oui[3];
 489                 __be16 ethertype;
 490         };
 491         struct llc_snap_hdr *llc;
 492         __be16 proto;
 493
 494         proto = *(__be16 *) skb->data;
 495         __skb_pull(skb, sizeof(__be16));
 496
 497         if (ntohs(proto) >= 1536)
 498                 return proto;
 499
 500         if (skb->len < sizeof(struct llc_snap_hdr))
 501                 return htons(ETH_P_802_2);
 502
 503         if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
 504                 return htons(0);
 505
 506         llc = (struct llc_snap_hdr *) skb->data;
 507         if (llc->dsap != LLC_SAP_SNAP ||
 508             llc->ssap != LLC_SAP_SNAP ||
 509             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
 510                 return htons(ETH_P_802_2);
 511
 512         __skb_pull(skb, sizeof(struct llc_snap_hdr));
 513         return llc->ethertype;
 514 }
 515
 516 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
 517                         int *key_lenp, int nh_len)
 518 {
 519         struct icmp6hdr *icmp = icmp6_hdr(skb);
 520         int error = 0;
 521         int key_len;
 522
 523         /* The ICMPv6 type and code fields use the 16-bit transport port
 524          * fields, so we need to store them in 16-bit network byte order.
 525          */
 526         key->ipv6.tp.src = htons(icmp->icmp6_type);
 527         key->ipv6.tp.dst = htons(icmp->icmp6_code);
 528         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 529
 530         if (icmp->icmp6_code == 0 &&
 531             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
 532              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 533                 int icmp_len = skb->len - skb_transport_offset(skb);
 534                 struct nd_msg *nd;
 535                 int offset;
 536
 537                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 538
 539                 /* In order to process neighbor discovery options, we need the
 540                  * entire packet.
 541                  */
 542                 if (unlikely(icmp_len < sizeof(*nd)))
 543                         goto out;
 544                 if (unlikely(skb_linearize(skb))) {
 545                         error = -ENOMEM;
 546                         goto out;
 547                 }
 548
 549                 nd = (struct nd_msg *)skb_transport_header(skb);
 550                 key->ipv6.nd.target = nd->target;
 551                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 552
 553                 icmp_len -= sizeof(*nd);
 554                 offset = 0;
 555                 while (icmp_len >= 8) {
 556                         struct nd_opt_hdr *nd_opt =
 557                                  (struct nd_opt_hdr *)(nd->opt + offset);
 558                         int opt_len = nd_opt->nd_opt_len * 8;
 559
 560                         if (unlikely(!opt_len || opt_len > icmp_len))
 561                                 goto invalid;
 562
 563                         /* Store the link layer address if the appropriate
 564                          * option is provided.  It is considered an error if
 565                          * the same link layer option is specified twice.
 566                          */
 567                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
 568                             && opt_len == 8) {
 569                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
 570                                         goto invalid;
 571                                 memcpy(key->ipv6.nd.sll,
 572                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 573                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
 574                                    && opt_len == 8) {
 575                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
 576                                         goto invalid;
 577                                 memcpy(key->ipv6.nd.tll,
 578                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 579                         }
 580
 581                         icmp_len -= opt_len;
 582                         offset += opt_len;
 583                 }
 584         }
 585
 586         goto out;
 587
 588 invalid:
 589         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
 590         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
 591         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
 592
 593 out:
 594         *key_lenp = key_len;
 595         return error;
 596 }
 597
 598 /**
 599  * ovs_flow_extract - extracts a flow key from an Ethernet frame.
 600  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 601  * Ethernet header
 602  * @in_port: port number on which @skb was received.
 603  * @key: output flow key
 604  * @key_lenp: length of output flow key
 605  *
 606  * The caller must ensure that skb->len >= ETH_HLEN.
 607  *
 608  * Returns 0 if successful, otherwise a negative errno value.
 609  *
 610  * Initializes @skb header pointers as follows:
 611  *
 612  *    - skb->mac_header: the Ethernet header.
 613  *
 614  *    - skb->network_header: just past the Ethernet header, or just past the
 615  *      VLAN header, to the first byte of the Ethernet payload.
 616  *
 617  *    - skb->transport_header: If key->dl_type is ETH_P_IP or ETH_P_IPV6
 618  *      on output, then just past the IP header, if one is present and
 619  *      of a correct length, otherwise the same as skb->network_header.
 620  *      For other key->dl_type values it is left untouched.
 621  */
 622 int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
 623                  int *key_lenp)
 624 {
 625         int error = 0;
 626         int key_len = SW_FLOW_KEY_OFFSET(eth);
 627         struct ethhdr *eth;
 628
 629         memset(key, 0, sizeof(*key));
 630
 631         key->phy.priority = skb->priority;
 632         key->phy.tun_id = OVS_CB(skb)->tun_id;
 633         key->phy.in_port = in_port;
 634
 635         skb_reset_mac_header(skb);
 636
 637         /* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
 638          * header in the linear data area.
 639          */
 640         eth = eth_hdr(skb);
 641         memcpy(key->eth.src, eth->h_source, ETH_ALEN);
 642         memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
 643
 644         __skb_pull(skb, 2 * ETH_ALEN);
 645
 646         if (vlan_tx_tag_present(skb))
 647                 key->eth.tci = htons(vlan_get_tci(skb));
 648         else if (eth->h_proto == htons(ETH_P_8021Q))
 649                 if (unlikely(parse_vlan(skb, key)))
 650                         return -ENOMEM;
 651
 652         key->eth.type = parse_ethertype(skb);
 653         if (unlikely(key->eth.type == htons(0)))
 654                 return -ENOMEM;
 655
 656         skb_reset_network_header(skb);
 657         __skb_push(skb, skb->data - skb_mac_header(skb));
 658
 659         /* Network layer. */
 660         if (key->eth.type == htons(ETH_P_IP)) {
 661                 struct iphdr *nh;
 662                 __be16 offset;
 663
 664                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
 665
 666                 error = check_iphdr(skb);
 667                 if (unlikely(error)) {
 668                         if (error == -EINVAL) {
 669                                 skb->transport_header = skb->network_header;
 670                                 error = 0;
 671                         }
 672                         goto out;
 673                 }
 674
 675                 nh = ip_hdr(skb);
 676                 key->ipv4.addr.src = nh->saddr;
 677                 key->ipv4.addr.dst = nh->daddr;
 678
 679                 key->ip.proto = nh->protocol;
 680                 key->ip.tos = nh->tos;
 681                 key->ip.ttl = nh->ttl;
 682
 683                 offset = nh->frag_off & htons(IP_OFFSET);
 684                 if (offset) {
 685                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 686                         goto out;
 687                 }
 688                 if (nh->frag_off & htons(IP_MF) ||
 689                          skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 690                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 691
 692                 /* Transport layer. */
 693                 if (key->ip.proto == IPPROTO_TCP) {
 694                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 695                         if (tcphdr_ok(skb)) {
 696                                 struct tcphdr *tcp = tcp_hdr(skb);
 697                                 key->ipv4.tp.src = tcp->source;
 698                                 key->ipv4.tp.dst = tcp->dest;
 699                         }
 700                 } else if (key->ip.proto == IPPROTO_UDP) {
 701                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 702                         if (udphdr_ok(skb)) {
 703                                 struct udphdr *udp = udp_hdr(skb);
 704                                 key->ipv4.tp.src = udp->source;
 705                                 key->ipv4.tp.dst = udp->dest;
 706                         }
 707                 } else if (key->ip.proto == IPPROTO_ICMP) {
 708                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 709                         if (icmphdr_ok(skb)) {
 710                                 struct icmphdr *icmp = icmp_hdr(skb);
 711                                 /* The ICMP type and code fields use the 16-bit
 712                                  * transport port fields, so we need to store
 713                                  * them in 16-bit network byte order. */
 714                                 key->ipv4.tp.src = htons(icmp->type);
 715                                 key->ipv4.tp.dst = htons(icmp->code);
 716                         }
 717                 }
 718
 719         } else if (key->eth.type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
 720                 struct arp_eth_header *arp;
 721
 722                 arp = (struct arp_eth_header *)skb_network_header(skb);
 723
 724                 if (arp->ar_hrd == htons(ARPHRD_ETHER)
 725                                 && arp->ar_pro == htons(ETH_P_IP)
 726                                 && arp->ar_hln == ETH_ALEN
 727                                 && arp->ar_pln == 4) {
 728
 729                         /* We only match on the lower 8 bits of the opcode. */
 730                         if (ntohs(arp->ar_op) <= 0xff)
 731                                 key->ip.proto = ntohs(arp->ar_op);
 732
 733                         if (key->ip.proto == ARPOP_REQUEST
 734                                         || key->ip.proto == ARPOP_REPLY) {
 735                                 memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
 736                                 memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
 737                                 memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
 738                                 memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
 739                                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
 740                         }
 741                 }
 742         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 743                 int nh_len;             /* IPv6 Header + Extensions */
 744
 745                 nh_len = parse_ipv6hdr(skb, key, &key_len);
 746                 if (unlikely(nh_len < 0)) {
 747                         if (nh_len == -EINVAL)
 748                                 skb->transport_header = skb->network_header;
 749                         else
 750                                 error = nh_len;
 751                         goto out;
 752                 }
 753
 754                 if (key->ip.frag == OVS_FRAG_TYPE_LATER)
 755                         goto out;
 756                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 757                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 758
 759                 /* Transport layer. */
 760                 if (key->ip.proto == NEXTHDR_TCP) {
 761                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 762                         if (tcphdr_ok(skb)) {
 763                                 struct tcphdr *tcp = tcp_hdr(skb);
 764                                 key->ipv6.tp.src = tcp->source;
 765                                 key->ipv6.tp.dst = tcp->dest;
 766                         }
 767                 } else if (key->ip.proto == NEXTHDR_UDP) {
 768                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 769                         if (udphdr_ok(skb)) {
 770                                 struct udphdr *udp = udp_hdr(skb);
 771                                 key->ipv6.tp.src = udp->source;
 772                                 key->ipv6.tp.dst = udp->dest;
 773                         }
 774                 } else if (key->ip.proto == NEXTHDR_ICMP) {
 775                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 776                         if (icmp6hdr_ok(skb)) {
 777                                 error = parse_icmpv6(skb, key, &key_len, nh_len);
 778                                 if (error < 0)
 779                                         goto out;
 780                         }
 781                 }
 782         }
 783
 784 out:
 785         *key_lenp = key_len;
 786         return error;
 787 }
 788
 789 u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len)
 790 {
 791         return jhash2((u32 *)key, DIV_ROUND_UP(key_len, sizeof(u32)), 0);
 792 }
 793
 794 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
 795                                 struct sw_flow_key *key, int key_len)
 796 {
 797         struct sw_flow *flow;
 798         struct hlist_node *n;
 799         struct hlist_head *head;
 800         u32 hash;
 801
 802         hash = ovs_flow_hash(key, key_len);
 803
 804         head = find_bucket(table, hash);
 805         hlist_for_each_entry_rcu(flow, n, head, hash_node[table->node_ver]) {
 806
 807                 if (flow->hash == hash &&
 808                     !memcmp(&flow->key, key, key_len)) {
 809                         return flow;
 810                 }
 811         }
 812         return NULL;
 813 }
 814
 815 void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
 816 {
 817         struct hlist_head *head;
 818
 819         head = find_bucket(table, flow->hash);
 820         hlist_add_head_rcu(&flow->hash_node[table->node_ver], head);
 821         table->count++;
 822 }
 823
 824 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
 825 {
 826         hlist_del_rcu(&flow->hash_node[table->node_ver]);
 827         table->count--;
 828         BUG_ON(table->count < 0);
 829 }
 830
 831 /* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
 832 const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
 833         [OVS_KEY_ATTR_ENCAP] = -1,
 834         [OVS_KEY_ATTR_PRIORITY] = sizeof(u32),
 835         [OVS_KEY_ATTR_IN_PORT] = sizeof(u32),
 836         [OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
 837         [OVS_KEY_ATTR_VLAN] = sizeof(__be16),
 838         [OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
 839         [OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
 840         [OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
 841         [OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
 842         [OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
 843         [OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
 844         [OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
 845         [OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
 846         [OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
 847
 848         /* Not upstream. */
 849         [OVS_KEY_ATTR_TUN_ID] = sizeof(__be64),
 850 };
 851
 852 static int ipv4_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 853                                   const struct nlattr *a[], u64 *attrs)
 854 {
 855         const struct ovs_key_icmp *icmp_key;
 856         const struct ovs_key_tcp *tcp_key;
 857         const struct ovs_key_udp *udp_key;
 858
 859         switch (swkey->ip.proto) {
 860         case IPPROTO_TCP:
 861                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 862                         return -EINVAL;
 863                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 864
 865                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 866                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 867                 swkey->ipv4.tp.src = tcp_key->tcp_src;
 868                 swkey->ipv4.tp.dst = tcp_key->tcp_dst;
 869                 break;
 870
 871         case IPPROTO_UDP:
 872                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 873                         return -EINVAL;
 874                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 875
 876                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 877                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 878                 swkey->ipv4.tp.src = udp_key->udp_src;
 879                 swkey->ipv4.tp.dst = udp_key->udp_dst;
 880                 break;
 881
 882         case IPPROTO_ICMP:
 883                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMP)))
 884                         return -EINVAL;
 885                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
 886
 887                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 888                 icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
 889                 swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
 890                 swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
 891                 break;
 892         }
 893
 894         return 0;
 895 }
 896
 897 static int ipv6_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 898                                   const struct nlattr *a[], u64 *attrs)
 899 {
 900         const struct ovs_key_icmpv6 *icmpv6_key;
 901         const struct ovs_key_tcp *tcp_key;
 902         const struct ovs_key_udp *udp_key;
 903
 904         switch (swkey->ip.proto) {
 905         case IPPROTO_TCP:
 906                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 907                         return -EINVAL;
 908                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 909
 910                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 911                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 912                 swkey->ipv6.tp.src = tcp_key->tcp_src;
 913                 swkey->ipv6.tp.dst = tcp_key->tcp_dst;
 914                 break;
 915
 916         case IPPROTO_UDP:
 917                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 918                         return -EINVAL;
 919                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 920
 921                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 922                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 923                 swkey->ipv6.tp.src = udp_key->udp_src;
 924                 swkey->ipv6.tp.dst = udp_key->udp_dst;
 925                 break;
 926
 927         case IPPROTO_ICMPV6:
 928                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMPV6)))
 929                         return -EINVAL;
 930                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
 931
 932                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 933                 icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
 934                 swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
 935                 swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
 936
 937                 if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
 938                     swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 939                         const struct ovs_key_nd *nd_key;
 940
 941                         if (!(*attrs & (1 << OVS_KEY_ATTR_ND)))
 942                                 return -EINVAL;
 943                         *attrs &= ~(1 << OVS_KEY_ATTR_ND);
 944
 945                         *key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 946                         nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
 947                         memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
 948                                sizeof(swkey->ipv6.nd.target));
 949                         memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
 950                         memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
 951                 }
 952                 break;
 953         }
 954
 955         return 0;
 956 }
 957
 958 static int parse_flow_nlattrs(const struct nlattr *attr,
 959                               const struct nlattr *a[], u64 *attrsp)
 960 {
 961         const struct nlattr *nla;
 962         u64 attrs;
 963         int rem;
 964
 965         attrs = 0;
 966         nla_for_each_nested(nla, attr, rem) {
 967                 u16 type = nla_type(nla);
 968                 int expected_len;
 969
 970                 if (type > OVS_KEY_ATTR_MAX || attrs & (1ULL << type))
 971                         return -EINVAL;
 972
 973                 expected_len = ovs_key_lens[type];
 974                 if (nla_len(nla) != expected_len && expected_len != -1)
 975                         return -EINVAL;
 976
 977                 attrs |= 1ULL << type;
 978                 a[type] = nla;
 979         }
 980         if (rem)
 981                 return -EINVAL;
 982
 983         *attrsp = attrs;
 984         return 0;
 985 }
 986
 987 /**
 988  * ovs_flow_from_nlattrs - parses Netlink attributes into a flow key.
 989  * @swkey: receives the extracted flow key.
 990  * @key_lenp: number of bytes used in @swkey.
 991  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
 992  * sequence.
 993  */
 994 int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
 995                       const struct nlattr *attr)
 996 {
 997         const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
 998         const struct ovs_key_ethernet *eth_key;
 999         int key_len;
1000         u64 attrs;
1001         int err;
1002
1003         memset(swkey, 0, sizeof(struct sw_flow_key));
1004         key_len = SW_FLOW_KEY_OFFSET(eth);
1005
1006         err = parse_flow_nlattrs(attr, a, &attrs);
1007         if (err)
1008                 return err;
1009
1010         /* Metadata attributes. */
1011         if (attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
1012                 swkey->phy.priority = nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]);
1013                 attrs &= ~(1 << OVS_KEY_ATTR_PRIORITY);
1014         }
1015         if (attrs & (1 << OVS_KEY_ATTR_IN_PORT)) {
1016                 u32 in_port = nla_get_u32(a[OVS_KEY_ATTR_IN_PORT]);
1017                 if (in_port >= DP_MAX_PORTS)
1018                         return -EINVAL;
1019                 swkey->phy.in_port = in_port;
1020                 attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
1021         } else {
1022                 swkey->phy.in_port = DP_MAX_PORTS;
1023         }
1024
1025         if (attrs & (1ULL << OVS_KEY_ATTR_TUN_ID)) {
1026                 swkey->phy.tun_id = nla_get_be64(a[OVS_KEY_ATTR_TUN_ID]);
1027                 attrs &= ~(1ULL << OVS_KEY_ATTR_TUN_ID);
1028         }
1029
1030         /* Data attributes. */
1031         if (!(attrs & (1 << OVS_KEY_ATTR_ETHERNET)))
1032                 return -EINVAL;
1033         attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
1034
1035         eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
1036         memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
1037         memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
1038
1039         if (attrs & (1u << OVS_KEY_ATTR_ETHERTYPE) &&
1040             nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q)) {
1041                 const struct nlattr *encap;
1042                 __be16 tci;
1043
1044                 if (attrs != ((1 << OVS_KEY_ATTR_VLAN) |
1045                               (1 << OVS_KEY_ATTR_ETHERTYPE) |
1046                               (1 << OVS_KEY_ATTR_ENCAP)))
1047                         return -EINVAL;
1048
1049                 encap = a[OVS_KEY_ATTR_ENCAP];
1050                 tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
1051                 if (tci & htons(VLAN_TAG_PRESENT)) {
1052                         swkey->eth.tci = tci;
1053
1054                         err = parse_flow_nlattrs(encap, a, &attrs);
1055                         if (err)
1056                                 return err;
1057                 } else if (!tci) {
1058                         /* Corner case for truncated 802.1Q header. */
1059                         if (nla_len(encap))
1060                                 return -EINVAL;
1061
1062                         swkey->eth.type = htons(ETH_P_8021Q);
1063                         *key_lenp = key_len;
1064                         return 0;
1065                 } else {
1066                         return -EINVAL;
1067                 }
1068         }
1069
1070         if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
1071                 swkey->eth.type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
1072                 if (ntohs(swkey->eth.type) < 1536)
1073                         return -EINVAL;
1074                 attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
1075         } else {
1076                 swkey->eth.type = htons(ETH_P_802_2);
1077         }
1078
1079         if (swkey->eth.type == htons(ETH_P_IP)) {
1080                 const struct ovs_key_ipv4 *ipv4_key;
1081
1082                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV4)))
1083                         return -EINVAL;
1084                 attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
1085
1086                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
1087                 ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
1088                 if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
1089                         return -EINVAL;
1090                 swkey->ip.proto = ipv4_key->ipv4_proto;
1091                 swkey->ip.tos = ipv4_key->ipv4_tos;
1092                 swkey->ip.ttl = ipv4_key->ipv4_ttl;
1093                 swkey->ip.frag = ipv4_key->ipv4_frag;
1094                 swkey->ipv4.addr.src = ipv4_key->ipv4_src;
1095                 swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
1096
1097                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1098                         err = ipv4_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1099                         if (err)
1100                                 return err;
1101                 }
1102         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1103                 const struct ovs_key_ipv6 *ipv6_key;
1104
1105                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV6)))
1106                         return -EINVAL;
1107                 attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
1108
1109                 key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
1110                 ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
1111                 if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
1112                         return -EINVAL;
1113                 swkey->ipv6.label = ipv6_key->ipv6_label;
1114                 swkey->ip.proto = ipv6_key->ipv6_proto;
1115                 swkey->ip.tos = ipv6_key->ipv6_tclass;
1116                 swkey->ip.ttl = ipv6_key->ipv6_hlimit;
1117                 swkey->ip.frag = ipv6_key->ipv6_frag;
1118                 memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
1119                        sizeof(swkey->ipv6.addr.src));
1120                 memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
1121                        sizeof(swkey->ipv6.addr.dst));
1122
1123                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1124                         err = ipv6_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1125                         if (err)
1126                                 return err;
1127                 }
1128         } else if (swkey->eth.type == htons(ETH_P_ARP)) {
1129                 const struct ovs_key_arp *arp_key;
1130
1131                 if (!(attrs & (1 << OVS_KEY_ATTR_ARP)))
1132                         return -EINVAL;
1133                 attrs &= ~(1 << OVS_KEY_ATTR_ARP);
1134
1135                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
1136                 arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
1137                 swkey->ipv4.addr.src = arp_key->arp_sip;
1138                 swkey->ipv4.addr.dst = arp_key->arp_tip;
1139                 if (arp_key->arp_op & htons(0xff00))
1140                         return -EINVAL;
1141                 swkey->ip.proto = ntohs(arp_key->arp_op);
1142                 memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
1143                 memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
1144         }
1145
1146         if (attrs)
1147                 return -EINVAL;
1148         *key_lenp = key_len;
1149
1150         return 0;
1151 }
1152
1153 /**
1154  * ovs_flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
1155  * @in_port: receives the extracted input port.
1156  * @tun_id: receives the extracted tunnel ID.
1157  * @key: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1158  * sequence.
1159  *
1160  * This parses a series of Netlink attributes that form a flow key, which must
1161  * take the same form accepted by flow_from_nlattrs(), but only enough of it to
1162  * get the metadata, that is, the parts of the flow key that cannot be
1163  * extracted from the packet itself.
1164  */
1165 int ovs_flow_metadata_from_nlattrs(u32 *priority, u16 *in_port, __be64 *tun_id,
1166                                    const struct nlattr *attr)
1167 {
1168         const struct nlattr *nla;
1169         int rem;
1170
1171         *in_port = DP_MAX_PORTS;
1172         *tun_id = 0;
1173         *priority = 0;
1174
1175         nla_for_each_nested(nla, attr, rem) {
1176                 int type = nla_type(nla);
1177
1178                 if (type <= OVS_KEY_ATTR_MAX && ovs_key_lens[type] > 0) {
1179                         if (nla_len(nla) != ovs_key_lens[type])
1180                                 return -EINVAL;
1181
1182                         switch (type) {
1183                         case OVS_KEY_ATTR_PRIORITY:
1184                                 *priority = nla_get_u32(nla);
1185                                 break;
1186
1187                         case OVS_KEY_ATTR_TUN_ID:
1188                                 *tun_id = nla_get_be64(nla);
1189                                 break;
1190
1191                         case OVS_KEY_ATTR_IN_PORT:
1192                                 if (nla_get_u32(nla) >= DP_MAX_PORTS)
1193                                         return -EINVAL;
1194                                 *in_port = nla_get_u32(nla);
1195                                 break;
1196                         }
1197                 }
1198         }
1199         if (rem)
1200                 return -EINVAL;
1201         return 0;
1202 }
1203
1204 int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
1205 {
1206         struct ovs_key_ethernet *eth_key;
1207         struct nlattr *nla, *encap;
1208
1209         if (swkey->phy.priority &&
1210             nla_put_u32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority))
1211                 goto nla_put_failure;
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                 goto nla_put_failure;
1216
1217         if (swkey->phy.in_port != DP_MAX_PORTS &&
1218             nla_put_u32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port))
1219                 goto nla_put_failure;
1220
1221         nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
1222         if (!nla)
1223                 goto nla_put_failure;
1224         eth_key = nla_data(nla);
1225         memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
1226         memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
1227
1228         if (swkey->eth.tci || swkey->eth.type == htons(ETH_P_8021Q)) {
1229                 if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, htons(ETH_P_8021Q)) ||
1230                     nla_put_be16(skb, OVS_KEY_ATTR_VLAN, swkey->eth.tci))
1231                         goto nla_put_failure;
1232                 encap = nla_nest_start(skb, OVS_KEY_ATTR_ENCAP);
1233                 if (!swkey->eth.tci)
1234                         goto unencap;
1235         } else {
1236                 encap = NULL;
1237         }
1238
1239         if (swkey->eth.type == htons(ETH_P_802_2))
1240                 goto unencap;
1241
1242         if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type))
1243                 goto nla_put_failure;
1244
1245         if (swkey->eth.type == htons(ETH_P_IP)) {
1246                 struct ovs_key_ipv4 *ipv4_key;
1247
1248                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
1249                 if (!nla)
1250                         goto nla_put_failure;
1251                 ipv4_key = nla_data(nla);
1252                 ipv4_key->ipv4_src = swkey->ipv4.addr.src;
1253                 ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
1254                 ipv4_key->ipv4_proto = swkey->ip.proto;
1255                 ipv4_key->ipv4_tos = swkey->ip.tos;
1256                 ipv4_key->ipv4_ttl = swkey->ip.ttl;
1257                 ipv4_key->ipv4_frag = swkey->ip.frag;
1258         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1259                 struct ovs_key_ipv6 *ipv6_key;
1260
1261                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
1262                 if (!nla)
1263                         goto nla_put_failure;
1264                 ipv6_key = nla_data(nla);
1265                 memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
1266                                 sizeof(ipv6_key->ipv6_src));
1267                 memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
1268                                 sizeof(ipv6_key->ipv6_dst));
1269                 ipv6_key->ipv6_label = swkey->ipv6.label;
1270                 ipv6_key->ipv6_proto = swkey->ip.proto;
1271                 ipv6_key->ipv6_tclass = swkey->ip.tos;
1272                 ipv6_key->ipv6_hlimit = swkey->ip.ttl;
1273                 ipv6_key->ipv6_frag = swkey->ip.frag;
1274         } else if (swkey->eth.type == htons(ETH_P_ARP)) {
1275                 struct ovs_key_arp *arp_key;
1276
1277                 nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
1278                 if (!nla)
1279                         goto nla_put_failure;
1280                 arp_key = nla_data(nla);
1281                 memset(arp_key, 0, sizeof(struct ovs_key_arp));
1282                 arp_key->arp_sip = swkey->ipv4.addr.src;
1283                 arp_key->arp_tip = swkey->ipv4.addr.dst;
1284                 arp_key->arp_op = htons(swkey->ip.proto);
1285                 memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1286                 memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1287         }
1288
1289         if ((swkey->eth.type == htons(ETH_P_IP) ||
1290              swkey->eth.type == htons(ETH_P_IPV6)) &&
1291              swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1292
1293                 if (swkey->ip.proto == IPPROTO_TCP) {
1294                         struct ovs_key_tcp *tcp_key;
1295
1296                         nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
1297                         if (!nla)
1298                                 goto nla_put_failure;
1299                         tcp_key = nla_data(nla);
1300                         if (swkey->eth.type == htons(ETH_P_IP)) {
1301                                 tcp_key->tcp_src = swkey->ipv4.tp.src;
1302                                 tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1303                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1304                                 tcp_key->tcp_src = swkey->ipv6.tp.src;
1305                                 tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1306                         }
1307                 } else if (swkey->ip.proto == IPPROTO_UDP) {
1308                         struct ovs_key_udp *udp_key;
1309
1310                         nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
1311                         if (!nla)
1312                                 goto nla_put_failure;
1313                         udp_key = nla_data(nla);
1314                         if (swkey->eth.type == htons(ETH_P_IP)) {
1315                                 udp_key->udp_src = swkey->ipv4.tp.src;
1316                                 udp_key->udp_dst = swkey->ipv4.tp.dst;
1317                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1318                                 udp_key->udp_src = swkey->ipv6.tp.src;
1319                                 udp_key->udp_dst = swkey->ipv6.tp.dst;
1320                         }
1321                 } else if (swkey->eth.type == htons(ETH_P_IP) &&
1322                            swkey->ip.proto == IPPROTO_ICMP) {
1323                         struct ovs_key_icmp *icmp_key;
1324
1325                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
1326                         if (!nla)
1327                                 goto nla_put_failure;
1328                         icmp_key = nla_data(nla);
1329                         icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1330                         icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1331                 } else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1332                            swkey->ip.proto == IPPROTO_ICMPV6) {
1333                         struct ovs_key_icmpv6 *icmpv6_key;
1334
1335                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
1336                                                 sizeof(*icmpv6_key));
1337                         if (!nla)
1338                                 goto nla_put_failure;
1339                         icmpv6_key = nla_data(nla);
1340                         icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1341                         icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1342
1343                         if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1344                             icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1345                                 struct ovs_key_nd *nd_key;
1346
1347                                 nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
1348                                 if (!nla)
1349                                         goto nla_put_failure;
1350                                 nd_key = nla_data(nla);
1351                                 memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1352                                                         sizeof(nd_key->nd_target));
1353                                 memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1354                                 memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1355                         }
1356                 }
1357         }
1358
1359 unencap:
1360         if (encap)
1361                 nla_nest_end(skb, encap);
1362
1363         return 0;
1364
1365 nla_put_failure:
1366         return -EMSGSIZE;
1367 }
1368
1369 /* Initializes the flow module.
1370  * Returns zero if successful or a negative error code. */
1371 int ovs_flow_init(void)
1372 {
1373         flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1374                                         0, NULL);
1375         if (flow_cache == NULL)
1376                 return -ENOMEM;
1377
1378         return 0;
1379 }
1380
1381 /* Uninitializes the flow module. */
1382 void ovs_flow_exit(void)
1383 {
1384         kmem_cache_destroy(flow_cache);
1385 }