datapath/flow.c

   1 /*
   2  * Copyright (c) 2007-2011 Nicira Networks.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of version 2 of the GNU General Public
   6  * License as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16  * 02110-1301, USA
  17  */
  18
  19 #include "flow.h"
  20 #include "datapath.h"
  21 #include <linux/uaccess.h>
  22 #include <linux/netdevice.h>
  23 #include <linux/etherdevice.h>
  24 #include <linux/if_ether.h>
  25 #include <linux/if_vlan.h>
  26 #include <net/llc_pdu.h>
  27 #include <linux/kernel.h>
  28 #include <linux/jhash.h>
  29 #include <linux/jiffies.h>
  30 #include <linux/llc.h>
  31 #include <linux/module.h>
  32 #include <linux/in.h>
  33 #include <linux/rcupdate.h>
  34 #include <linux/if_arp.h>
  35 #include <linux/if_ether.h>
  36 #include <linux/ip.h>
  37 #include <linux/ipv6.h>
  38 #include <linux/tcp.h>
  39 #include <linux/udp.h>
  40 #include <linux/icmp.h>
  41 #include <linux/icmpv6.h>
  42 #include <linux/rculist.h>
  43 #include <net/ip.h>
  44 #include <net/ipv6.h>
  45 #include <net/ndisc.h>
  46
  47 #include "vlan.h"
  48
  49 static struct kmem_cache *flow_cache;
  50 static unsigned int hash_seed __read_mostly;
  51
  52 static int check_header(struct sk_buff *skb, int len)
  53 {
  54         if (unlikely(skb->len < len))
  55                 return -EINVAL;
  56         if (unlikely(!pskb_may_pull(skb, len)))
  57                 return -ENOMEM;
  58         return 0;
  59 }
  60
  61 static bool arphdr_ok(struct sk_buff *skb)
  62 {
  63         return pskb_may_pull(skb, skb_network_offset(skb) +
  64                                   sizeof(struct arp_eth_header));
  65 }
  66
  67 static int check_iphdr(struct sk_buff *skb)
  68 {
  69         unsigned int nh_ofs = skb_network_offset(skb);
  70         unsigned int ip_len;
  71         int err;
  72
  73         err = check_header(skb, nh_ofs + sizeof(struct iphdr));
  74         if (unlikely(err))
  75                 return err;
  76
  77         ip_len = ip_hdrlen(skb);
  78         if (unlikely(ip_len < sizeof(struct iphdr) ||
  79                      skb->len < nh_ofs + ip_len))
  80                 return -EINVAL;
  81
  82         skb_set_transport_header(skb, nh_ofs + ip_len);
  83         return 0;
  84 }
  85
  86 static bool tcphdr_ok(struct sk_buff *skb)
  87 {
  88         int th_ofs = skb_transport_offset(skb);
  89         int tcp_len;
  90
  91         if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
  92                 return false;
  93
  94         tcp_len = tcp_hdrlen(skb);
  95         if (unlikely(tcp_len < sizeof(struct tcphdr) ||
  96                      skb->len < th_ofs + tcp_len))
  97                 return false;
  98
  99         return true;
 100 }
 101
 102 static bool udphdr_ok(struct sk_buff *skb)
 103 {
 104         return pskb_may_pull(skb, skb_transport_offset(skb) +
 105                                   sizeof(struct udphdr));
 106 }
 107
 108 static bool icmphdr_ok(struct sk_buff *skb)
 109 {
 110         return pskb_may_pull(skb, skb_transport_offset(skb) +
 111                                   sizeof(struct icmphdr));
 112 }
 113
 114 u64 ovs_flow_used_time(unsigned long flow_jiffies)
 115 {
 116         struct timespec cur_ts;
 117         u64 cur_ms, idle_ms;
 118
 119         ktime_get_ts(&cur_ts);
 120         idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
 121         cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
 122                  cur_ts.tv_nsec / NSEC_PER_MSEC;
 123
 124         return cur_ms - idle_ms;
 125 }
 126
 127 #define SW_FLOW_KEY_OFFSET(field)               \
 128         (offsetof(struct sw_flow_key, field) +  \
 129          FIELD_SIZEOF(struct sw_flow_key, field))
 130
 131 /**
 132  * skip_exthdr - skip any IPv6 extension headers
 133  * @skb: skbuff to parse
 134  * @start: offset of first extension header
 135  * @nexthdrp: Initially, points to the type of the extension header at @start.
 136  * This function updates it to point to the extension header at the final
 137  * offset.
 138  * @frag: Points to the @frag member in a &struct sw_flow_key.  This
 139  * function sets an appropriate %OVS_FRAG_TYPE_* value.
 140  *
 141  * This is based on ipv6_skip_exthdr() but adds the updates to *@frag.
 142  *
 143  * When there is more than one fragment header, this version reports whether
 144  * the final fragment header that it examines is a first fragment.
 145  *
 146  * Returns the final payload offset, or -1 on error.
 147  */
 148 static int skip_exthdr(const struct sk_buff *skb, int start, u8 *nexthdrp,
 149                        u8 *frag)
 150 {
 151         u8 nexthdr = *nexthdrp;
 152
 153         while (ipv6_ext_hdr(nexthdr)) {
 154                 struct ipv6_opt_hdr _hdr, *hp;
 155                 int hdrlen;
 156
 157                 if (nexthdr == NEXTHDR_NONE)
 158                         return -1;
 159                 hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr);
 160                 if (hp == NULL)
 161                         return -1;
 162                 if (nexthdr == NEXTHDR_FRAGMENT) {
 163                         __be16 _frag_off, *fp;
 164                         fp = skb_header_pointer(skb,
 165                                                 start+offsetof(struct frag_hdr,
 166                                                                frag_off),
 167                                                 sizeof(_frag_off),
 168                                                 &_frag_off);
 169                         if (fp == NULL)
 170                                 return -1;
 171
 172                         if (ntohs(*fp) & ~0x7) {
 173                                 *frag = OVS_FRAG_TYPE_LATER;
 174                                 break;
 175                         }
 176                         *frag = OVS_FRAG_TYPE_FIRST;
 177                         hdrlen = 8;
 178                 } else if (nexthdr == NEXTHDR_AUTH)
 179                         hdrlen = (hp->hdrlen+2)<<2;
 180                 else
 181                         hdrlen = ipv6_optlen(hp);
 182
 183                 nexthdr = hp->nexthdr;
 184                 start += hdrlen;
 185         }
 186
 187         *nexthdrp = nexthdr;
 188         return start;
 189 }
 190
 191 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key,
 192                          int *key_lenp)
 193 {
 194         unsigned int nh_ofs = skb_network_offset(skb);
 195         unsigned int nh_len;
 196         int payload_ofs;
 197         struct ipv6hdr *nh;
 198         uint8_t nexthdr;
 199         int err;
 200
 201         *key_lenp = SW_FLOW_KEY_OFFSET(ipv6.label);
 202
 203         err = check_header(skb, nh_ofs + sizeof(*nh));
 204         if (unlikely(err))
 205                 return err;
 206
 207         nh = ipv6_hdr(skb);
 208         nexthdr = nh->nexthdr;
 209         payload_ofs = (u8 *)(nh + 1) - skb->data;
 210
 211         key->ip.proto = NEXTHDR_NONE;
 212         key->ip.tos = ipv6_get_dsfield(nh);
 213         key->ip.ttl = nh->hop_limit;
 214         key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 215         ipv6_addr_copy(&key->ipv6.addr.src, &nh->saddr);
 216         ipv6_addr_copy(&key->ipv6.addr.dst, &nh->daddr);
 217
 218         payload_ofs = skip_exthdr(skb, payload_ofs, &nexthdr, &key->ip.frag);
 219         if (unlikely(payload_ofs < 0))
 220                 return -EINVAL;
 221
 222         nh_len = payload_ofs - nh_ofs;
 223         skb_set_transport_header(skb, nh_ofs + nh_len);
 224         key->ip.proto = nexthdr;
 225         return nh_len;
 226 }
 227
 228 static bool icmp6hdr_ok(struct sk_buff *skb)
 229 {
 230         return pskb_may_pull(skb, skb_transport_offset(skb) +
 231                                   sizeof(struct icmp6hdr));
 232 }
 233
 234 #define TCP_FLAGS_OFFSET 13
 235 #define TCP_FLAG_MASK 0x3f
 236
 237 void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb)
 238 {
 239         u8 tcp_flags = 0;
 240
 241         if (flow->key.eth.type == htons(ETH_P_IP) &&
 242             flow->key.ip.proto == IPPROTO_TCP) {
 243                 u8 *tcp = (u8 *)tcp_hdr(skb);
 244                 tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
 245         }
 246
 247         spin_lock(&flow->lock);
 248         flow->used = jiffies;
 249         flow->packet_count++;
 250         flow->byte_count += skb->len;
 251         flow->tcp_flags |= tcp_flags;
 252         spin_unlock(&flow->lock);
 253 }
 254
 255 struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *actions)
 256 {
 257         int actions_len = nla_len(actions);
 258         struct sw_flow_actions *sfa;
 259
 260         /* At least DP_MAX_PORTS actions are required to be able to flood a
 261          * packet to every port.  Factor of 2 allows for setting VLAN tags,
 262          * etc. */
 263         if (actions_len > 2 * DP_MAX_PORTS * nla_total_size(4))
 264                 return ERR_PTR(-EINVAL);
 265
 266         sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
 267         if (!sfa)
 268                 return ERR_PTR(-ENOMEM);
 269
 270         sfa->actions_len = actions_len;
 271         memcpy(sfa->actions, nla_data(actions), actions_len);
 272         return sfa;
 273 }
 274
 275 struct sw_flow *ovs_flow_alloc(void)
 276 {
 277         struct sw_flow *flow;
 278
 279         flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
 280         if (!flow)
 281                 return ERR_PTR(-ENOMEM);
 282
 283         spin_lock_init(&flow->lock);
 284         atomic_set(&flow->refcnt, 1);
 285         flow->sf_acts = NULL;
 286         flow->dead = false;
 287
 288         return flow;
 289 }
 290
 291 static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
 292 {
 293         return flex_array_get(table->buckets,
 294                                 (hash & (table->n_buckets - 1)));
 295 }
 296
 297 static struct flex_array *alloc_buckets(unsigned int n_buckets)
 298 {
 299         struct flex_array *buckets;
 300         int i, err;
 301
 302         buckets = flex_array_alloc(sizeof(struct hlist_head *),
 303                                    n_buckets, GFP_KERNEL);
 304         if (!buckets)
 305                 return NULL;
 306
 307         err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
 308         if (err) {
 309                 flex_array_free(buckets);
 310                 return NULL;
 311         }
 312
 313         for (i = 0; i < n_buckets; i++)
 314                 INIT_HLIST_HEAD((struct hlist_head *)
 315                                         flex_array_get(buckets, i));
 316
 317         return buckets;
 318 }
 319
 320 static void free_buckets(struct flex_array *buckets)
 321 {
 322         flex_array_free(buckets);
 323 }
 324
 325 struct flow_table *ovs_flow_tbl_alloc(int new_size)
 326 {
 327         struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
 328
 329         if (!table)
 330                 return NULL;
 331
 332         table->buckets = alloc_buckets(new_size);
 333
 334         if (!table->buckets) {
 335                 kfree(table);
 336                 return NULL;
 337         }
 338         table->n_buckets = new_size;
 339         table->count = 0;
 340
 341         return table;
 342 }
 343
 344 static void flow_free(struct sw_flow *flow)
 345 {
 346         flow->dead = true;
 347         ovs_flow_put(flow);
 348 }
 349
 350 void ovs_flow_tbl_destroy(struct flow_table *table)
 351 {
 352         int i;
 353
 354         if (!table)
 355                 return;
 356
 357         for (i = 0; i < table->n_buckets; i++) {
 358                 struct sw_flow *flow;
 359                 struct hlist_head *head = flex_array_get(table->buckets, i);
 360                 struct hlist_node *node, *n;
 361
 362                 hlist_for_each_entry_safe(flow, node, n, head, hash_node) {
 363                         hlist_del_init_rcu(&flow->hash_node);
 364                         flow_free(flow);
 365                 }
 366         }
 367
 368         free_buckets(table->buckets);
 369         kfree(table);
 370 }
 371
 372 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
 373 {
 374         struct flow_table *table = container_of(rcu, struct flow_table, rcu);
 375
 376         ovs_flow_tbl_destroy(table);
 377 }
 378
 379 void ovs_flow_tbl_deferred_destroy(struct flow_table *table)
 380 {
 381         if (!table)
 382                 return;
 383
 384         call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
 385 }
 386
 387 struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
 388 {
 389         struct sw_flow *flow;
 390         struct hlist_head *head;
 391         struct hlist_node *n;
 392         int i;
 393
 394         while (*bucket < table->n_buckets) {
 395                 i = 0;
 396                 head = flex_array_get(table->buckets, *bucket);
 397                 hlist_for_each_entry_rcu(flow, n, head, hash_node) {
 398                         if (i < *last) {
 399                                 i++;
 400                                 continue;
 401                         }
 402                         *last = i + 1;
 403                         return flow;
 404                 }
 405                 (*bucket)++;
 406                 *last = 0;
 407         }
 408
 409         return NULL;
 410 }
 411
 412 struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
 413 {
 414         struct flow_table *new_table;
 415         int n_buckets = table->n_buckets * 2;
 416         int i;
 417
 418         new_table = ovs_flow_tbl_alloc(n_buckets);
 419         if (!new_table)
 420                 return ERR_PTR(-ENOMEM);
 421
 422         for (i = 0; i < table->n_buckets; i++) {
 423                 struct sw_flow *flow;
 424                 struct hlist_head *head;
 425                 struct hlist_node *n, *pos;
 426
 427                 head = flex_array_get(table->buckets, i);
 428
 429                 hlist_for_each_entry_safe(flow, n, pos, head, hash_node) {
 430                         hlist_del_init_rcu(&flow->hash_node);
 431                         ovs_flow_tbl_insert(new_table, flow);
 432                 }
 433         }
 434
 435         return new_table;
 436 }
 437
 438 /* RCU callback used by ovs_flow_deferred_free. */
 439 static void rcu_free_flow_callback(struct rcu_head *rcu)
 440 {
 441         struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
 442
 443         flow->dead = true;
 444         ovs_flow_put(flow);
 445 }
 446
 447 /* Schedules 'flow' to be freed after the next RCU grace period.
 448  * The caller must hold rcu_read_lock for this to be sensible. */
 449 void ovs_flow_deferred_free(struct sw_flow *flow)
 450 {
 451         call_rcu(&flow->rcu, rcu_free_flow_callback);
 452 }
 453
 454 void ovs_flow_hold(struct sw_flow *flow)
 455 {
 456         atomic_inc(&flow->refcnt);
 457 }
 458
 459 void ovs_flow_put(struct sw_flow *flow)
 460 {
 461         if (unlikely(!flow))
 462                 return;
 463
 464         if (atomic_dec_and_test(&flow->refcnt)) {
 465                 kfree((struct sf_flow_acts __force *)flow->sf_acts);
 466                 kmem_cache_free(flow_cache, flow);
 467         }
 468 }
 469
 470 /* RCU callback used by ovs_flow_deferred_free_acts. */
 471 static void rcu_free_acts_callback(struct rcu_head *rcu)
 472 {
 473         struct sw_flow_actions *sf_acts = container_of(rcu,
 474                         struct sw_flow_actions, rcu);
 475         kfree(sf_acts);
 476 }
 477
 478 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
 479  * The caller must hold rcu_read_lock for this to be sensible. */
 480 void ovs_flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
 481 {
 482         call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
 483 }
 484
 485 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 486 {
 487         struct qtag_prefix {
 488                 __be16 eth_type; /* ETH_P_8021Q */
 489                 __be16 tci;
 490         };
 491         struct qtag_prefix *qp;
 492
 493         if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
 494                 return 0;
 495
 496         if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
 497                                          sizeof(__be16))))
 498                 return -ENOMEM;
 499
 500         qp = (struct qtag_prefix *) skb->data;
 501         key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
 502         __skb_pull(skb, sizeof(struct qtag_prefix));
 503
 504         return 0;
 505 }
 506
 507 static __be16 parse_ethertype(struct sk_buff *skb)
 508 {
 509         struct llc_snap_hdr {
 510                 u8  dsap;  /* Always 0xAA */
 511                 u8  ssap;  /* Always 0xAA */
 512                 u8  ctrl;
 513                 u8  oui[3];
 514                 __be16 ethertype;
 515         };
 516         struct llc_snap_hdr *llc;
 517         __be16 proto;
 518
 519         proto = *(__be16 *) skb->data;
 520         __skb_pull(skb, sizeof(__be16));
 521
 522         if (ntohs(proto) >= 1536)
 523                 return proto;
 524
 525         if (skb->len < sizeof(struct llc_snap_hdr))
 526                 return htons(ETH_P_802_2);
 527
 528         if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
 529                 return htons(0);
 530
 531         llc = (struct llc_snap_hdr *) skb->data;
 532         if (llc->dsap != LLC_SAP_SNAP ||
 533             llc->ssap != LLC_SAP_SNAP ||
 534             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
 535                 return htons(ETH_P_802_2);
 536
 537         __skb_pull(skb, sizeof(struct llc_snap_hdr));
 538         return llc->ethertype;
 539 }
 540
 541 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
 542                         int *key_lenp, int nh_len)
 543 {
 544         struct icmp6hdr *icmp = icmp6_hdr(skb);
 545         int error = 0;
 546         int key_len;
 547
 548         /* The ICMPv6 type and code fields use the 16-bit transport port
 549          * fields, so we need to store them in 16-bit network byte order.
 550          */
 551         key->ipv6.tp.src = htons(icmp->icmp6_type);
 552         key->ipv6.tp.dst = htons(icmp->icmp6_code);
 553         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 554
 555         if (icmp->icmp6_code == 0 &&
 556             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
 557              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 558                 int icmp_len = skb->len - skb_transport_offset(skb);
 559                 struct nd_msg *nd;
 560                 int offset;
 561
 562                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 563
 564                 /* In order to process neighbor discovery options, we need the
 565                  * entire packet.
 566                  */
 567                 if (unlikely(icmp_len < sizeof(*nd)))
 568                         goto out;
 569                 if (unlikely(skb_linearize(skb))) {
 570                         error = -ENOMEM;
 571                         goto out;
 572                 }
 573
 574                 nd = (struct nd_msg *)skb_transport_header(skb);
 575                 ipv6_addr_copy(&key->ipv6.nd.target, &nd->target);
 576                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 577
 578                 icmp_len -= sizeof(*nd);
 579                 offset = 0;
 580                 while (icmp_len >= 8) {
 581                         struct nd_opt_hdr *nd_opt =
 582                                  (struct nd_opt_hdr *)(nd->opt + offset);
 583                         int opt_len = nd_opt->nd_opt_len * 8;
 584
 585                         if (unlikely(!opt_len || opt_len > icmp_len))
 586                                 goto invalid;
 587
 588                         /* Store the link layer address if the appropriate
 589                          * option is provided.  It is considered an error if
 590                          * the same link layer option is specified twice.
 591                          */
 592                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
 593                             && opt_len == 8) {
 594                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
 595                                         goto invalid;
 596                                 memcpy(key->ipv6.nd.sll,
 597                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 598                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
 599                                    && opt_len == 8) {
 600                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
 601                                         goto invalid;
 602                                 memcpy(key->ipv6.nd.tll,
 603                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 604                         }
 605
 606                         icmp_len -= opt_len;
 607                         offset += opt_len;
 608                 }
 609         }
 610
 611         goto out;
 612
 613 invalid:
 614         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
 615         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
 616         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
 617
 618 out:
 619         *key_lenp = key_len;
 620         return error;
 621 }
 622
 623 /**
 624  * ovs_flow_extract - extracts a flow key from an Ethernet frame.
 625  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 626  * Ethernet header
 627  * @in_port: port number on which @skb was received.
 628  * @key: output flow key
 629  * @key_lenp: length of output flow key
 630  *
 631  * The caller must ensure that skb->len >= ETH_HLEN.
 632  *
 633  * Returns 0 if successful, otherwise a negative errno value.
 634  *
 635  * Initializes @skb header pointers as follows:
 636  *
 637  *    - skb->mac_header: the Ethernet header.
 638  *
 639  *    - skb->network_header: just past the Ethernet header, or just past the
 640  *      VLAN header, to the first byte of the Ethernet payload.
 641  *
 642  *    - skb->transport_header: If key->dl_type is ETH_P_IP or ETH_P_IPV6
 643  *      on output, then just past the IP header, if one is present and
 644  *      of a correct length, otherwise the same as skb->network_header.
 645  *      For other key->dl_type values it is left untouched.
 646  */
 647 int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
 648                  int *key_lenp)
 649 {
 650         int error = 0;
 651         int key_len = SW_FLOW_KEY_OFFSET(eth);
 652         struct ethhdr *eth;
 653
 654         memset(key, 0, sizeof(*key));
 655
 656         key->phy.priority = skb->priority;
 657         key->phy.tun_id = OVS_CB(skb)->tun_id;
 658         key->phy.in_port = in_port;
 659
 660         skb_reset_mac_header(skb);
 661
 662         /* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
 663          * header in the linear data area.
 664          */
 665         eth = eth_hdr(skb);
 666         memcpy(key->eth.src, eth->h_source, ETH_ALEN);
 667         memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
 668
 669         __skb_pull(skb, 2 * ETH_ALEN);
 670
 671         if (vlan_tx_tag_present(skb))
 672                 key->eth.tci = htons(vlan_get_tci(skb));
 673         else if (eth->h_proto == htons(ETH_P_8021Q))
 674                 if (unlikely(parse_vlan(skb, key)))
 675                         return -ENOMEM;
 676
 677         key->eth.type = parse_ethertype(skb);
 678         if (unlikely(key->eth.type == htons(0)))
 679                 return -ENOMEM;
 680
 681         skb_reset_network_header(skb);
 682         __skb_push(skb, skb->data - skb_mac_header(skb));
 683
 684         /* Network layer. */
 685         if (key->eth.type == htons(ETH_P_IP)) {
 686                 struct iphdr *nh;
 687                 __be16 offset;
 688
 689                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
 690
 691                 error = check_iphdr(skb);
 692                 if (unlikely(error)) {
 693                         if (error == -EINVAL) {
 694                                 skb->transport_header = skb->network_header;
 695                                 error = 0;
 696                         }
 697                         goto out;
 698                 }
 699
 700                 nh = ip_hdr(skb);
 701                 key->ipv4.addr.src = nh->saddr;
 702                 key->ipv4.addr.dst = nh->daddr;
 703
 704                 key->ip.proto = nh->protocol;
 705                 key->ip.tos = nh->tos;
 706                 key->ip.ttl = nh->ttl;
 707
 708                 offset = nh->frag_off & htons(IP_OFFSET);
 709                 if (offset) {
 710                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 711                         goto out;
 712                 }
 713                 if (nh->frag_off & htons(IP_MF) ||
 714                          skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 715                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 716
 717                 /* Transport layer. */
 718                 if (key->ip.proto == IPPROTO_TCP) {
 719                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 720                         if (tcphdr_ok(skb)) {
 721                                 struct tcphdr *tcp = tcp_hdr(skb);
 722                                 key->ipv4.tp.src = tcp->source;
 723                                 key->ipv4.tp.dst = tcp->dest;
 724                         }
 725                 } else if (key->ip.proto == IPPROTO_UDP) {
 726                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 727                         if (udphdr_ok(skb)) {
 728                                 struct udphdr *udp = udp_hdr(skb);
 729                                 key->ipv4.tp.src = udp->source;
 730                                 key->ipv4.tp.dst = udp->dest;
 731                         }
 732                 } else if (key->ip.proto == IPPROTO_ICMP) {
 733                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 734                         if (icmphdr_ok(skb)) {
 735                                 struct icmphdr *icmp = icmp_hdr(skb);
 736                                 /* The ICMP type and code fields use the 16-bit
 737                                  * transport port fields, so we need to store
 738                                  * them in 16-bit network byte order. */
 739                                 key->ipv4.tp.src = htons(icmp->type);
 740                                 key->ipv4.tp.dst = htons(icmp->code);
 741                         }
 742                 }
 743
 744         } else if (key->eth.type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
 745                 struct arp_eth_header *arp;
 746
 747                 arp = (struct arp_eth_header *)skb_network_header(skb);
 748
 749                 if (arp->ar_hrd == htons(ARPHRD_ETHER)
 750                                 && arp->ar_pro == htons(ETH_P_IP)
 751                                 && arp->ar_hln == ETH_ALEN
 752                                 && arp->ar_pln == 4) {
 753
 754                         /* We only match on the lower 8 bits of the opcode. */
 755                         if (ntohs(arp->ar_op) <= 0xff)
 756                                 key->ip.proto = ntohs(arp->ar_op);
 757
 758                         if (key->ip.proto == ARPOP_REQUEST
 759                                         || key->ip.proto == ARPOP_REPLY) {
 760                                 memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
 761                                 memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
 762                                 memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
 763                                 memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
 764                                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
 765                         }
 766                 }
 767         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 768                 int nh_len;             /* IPv6 Header + Extensions */
 769
 770                 nh_len = parse_ipv6hdr(skb, key, &key_len);
 771                 if (unlikely(nh_len < 0)) {
 772                         if (nh_len == -EINVAL)
 773                                 skb->transport_header = skb->network_header;
 774                         else
 775                                 error = nh_len;
 776                         goto out;
 777                 }
 778
 779                 if (key->ip.frag == OVS_FRAG_TYPE_LATER)
 780                         goto out;
 781                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 782                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 783
 784                 /* Transport layer. */
 785                 if (key->ip.proto == NEXTHDR_TCP) {
 786                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 787                         if (tcphdr_ok(skb)) {
 788                                 struct tcphdr *tcp = tcp_hdr(skb);
 789                                 key->ipv6.tp.src = tcp->source;
 790                                 key->ipv6.tp.dst = tcp->dest;
 791                         }
 792                 } else if (key->ip.proto == NEXTHDR_UDP) {
 793                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 794                         if (udphdr_ok(skb)) {
 795                                 struct udphdr *udp = udp_hdr(skb);
 796                                 key->ipv6.tp.src = udp->source;
 797                                 key->ipv6.tp.dst = udp->dest;
 798                         }
 799                 } else if (key->ip.proto == NEXTHDR_ICMP) {
 800                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 801                         if (icmp6hdr_ok(skb)) {
 802                                 error = parse_icmpv6(skb, key, &key_len, nh_len);
 803                                 if (error < 0)
 804                                         goto out;
 805                         }
 806                 }
 807         }
 808
 809 out:
 810         *key_lenp = key_len;
 811         return error;
 812 }
 813
 814 u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len)
 815 {
 816         return jhash2((u32 *)key, DIV_ROUND_UP(key_len, sizeof(u32)), hash_seed);
 817 }
 818
 819 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
 820                                 struct sw_flow_key *key, int key_len)
 821 {
 822         struct sw_flow *flow;
 823         struct hlist_node *n;
 824         struct hlist_head *head;
 825         u32 hash;
 826
 827         hash = ovs_flow_hash(key, key_len);
 828
 829         head = find_bucket(table, hash);
 830         hlist_for_each_entry_rcu(flow, n, head, hash_node) {
 831
 832                 if (flow->hash == hash &&
 833                     !memcmp(&flow->key, key, key_len)) {
 834                         return flow;
 835                 }
 836         }
 837         return NULL;
 838 }
 839
 840 void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
 841 {
 842         struct hlist_head *head;
 843
 844         head = find_bucket(table, flow->hash);
 845         hlist_add_head_rcu(&flow->hash_node, head);
 846         table->count++;
 847 }
 848
 849 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
 850 {
 851         if (!hlist_unhashed(&flow->hash_node)) {
 852                 hlist_del_init_rcu(&flow->hash_node);
 853                 table->count--;
 854                 BUG_ON(table->count < 0);
 855         }
 856 }
 857
 858 /* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
 859 const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
 860         [OVS_KEY_ATTR_ENCAP] = -1,
 861         [OVS_KEY_ATTR_PRIORITY] = sizeof(u32),
 862         [OVS_KEY_ATTR_IN_PORT] = sizeof(u32),
 863         [OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
 864         [OVS_KEY_ATTR_VLAN] = sizeof(__be16),
 865         [OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
 866         [OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
 867         [OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
 868         [OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
 869         [OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
 870         [OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
 871         [OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
 872         [OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
 873         [OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
 874
 875         /* Not upstream. */
 876         [OVS_KEY_ATTR_TUN_ID] = sizeof(__be64),
 877 };
 878
 879 static int ipv4_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 880                                   const struct nlattr *a[], u64 *attrs)
 881 {
 882         const struct ovs_key_icmp *icmp_key;
 883         const struct ovs_key_tcp *tcp_key;
 884         const struct ovs_key_udp *udp_key;
 885
 886         switch (swkey->ip.proto) {
 887         case IPPROTO_TCP:
 888                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 889                         return -EINVAL;
 890                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 891
 892                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 893                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 894                 swkey->ipv4.tp.src = tcp_key->tcp_src;
 895                 swkey->ipv4.tp.dst = tcp_key->tcp_dst;
 896                 break;
 897
 898         case IPPROTO_UDP:
 899                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 900                         return -EINVAL;
 901                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 902
 903                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 904                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 905                 swkey->ipv4.tp.src = udp_key->udp_src;
 906                 swkey->ipv4.tp.dst = udp_key->udp_dst;
 907                 break;
 908
 909         case IPPROTO_ICMP:
 910                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMP)))
 911                         return -EINVAL;
 912                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
 913
 914                 *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 915                 icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
 916                 swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
 917                 swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
 918                 break;
 919         }
 920
 921         return 0;
 922 }
 923
 924 static int ipv6_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
 925                                   const struct nlattr *a[], u64 *attrs)
 926 {
 927         const struct ovs_key_icmpv6 *icmpv6_key;
 928         const struct ovs_key_tcp *tcp_key;
 929         const struct ovs_key_udp *udp_key;
 930
 931         switch (swkey->ip.proto) {
 932         case IPPROTO_TCP:
 933                 if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
 934                         return -EINVAL;
 935                 *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
 936
 937                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 938                 tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
 939                 swkey->ipv6.tp.src = tcp_key->tcp_src;
 940                 swkey->ipv6.tp.dst = tcp_key->tcp_dst;
 941                 break;
 942
 943         case IPPROTO_UDP:
 944                 if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
 945                         return -EINVAL;
 946                 *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
 947
 948                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 949                 udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
 950                 swkey->ipv6.tp.src = udp_key->udp_src;
 951                 swkey->ipv6.tp.dst = udp_key->udp_dst;
 952                 break;
 953
 954         case IPPROTO_ICMPV6:
 955                 if (!(*attrs & (1 << OVS_KEY_ATTR_ICMPV6)))
 956                         return -EINVAL;
 957                 *attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
 958
 959                 *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 960                 icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
 961                 swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
 962                 swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
 963
 964                 if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
 965                     swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 966                         const struct ovs_key_nd *nd_key;
 967
 968                         if (!(*attrs & (1 << OVS_KEY_ATTR_ND)))
 969                                 return -EINVAL;
 970                         *attrs &= ~(1 << OVS_KEY_ATTR_ND);
 971
 972                         *key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 973                         nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
 974                         memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
 975                                sizeof(swkey->ipv6.nd.target));
 976                         memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
 977                         memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
 978                 }
 979                 break;
 980         }
 981
 982         return 0;
 983 }
 984
 985 static int parse_flow_nlattrs(const struct nlattr *attr,
 986                               const struct nlattr *a[], u64 *attrsp)
 987 {
 988         const struct nlattr *nla;
 989         u64 attrs;
 990         int rem;
 991
 992         attrs = 0;
 993         nla_for_each_nested(nla, attr, rem) {
 994                 u16 type = nla_type(nla);
 995                 int expected_len;
 996
 997                 if (type > OVS_KEY_ATTR_MAX || attrs & (1ULL << type))
 998                         return -EINVAL;
 999
1000                 expected_len = ovs_key_lens[type];
1001                 if (nla_len(nla) != expected_len && expected_len != -1)
1002                         return -EINVAL;
1003
1004                 attrs |= 1ULL << type;
1005                 a[type] = nla;
1006         }
1007         if (rem)
1008                 return -EINVAL;
1009
1010         *attrsp = attrs;
1011         return 0;
1012 }
1013
1014 /**
1015  * ovs_flow_from_nlattrs - parses Netlink attributes into a flow key.
1016  * @swkey: receives the extracted flow key.
1017  * @key_lenp: number of bytes used in @swkey.
1018  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1019  * sequence.
1020  */
1021 int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
1022                       const struct nlattr *attr)
1023 {
1024         const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
1025         const struct ovs_key_ethernet *eth_key;
1026         int key_len;
1027         u64 attrs;
1028         int err;
1029
1030         memset(swkey, 0, sizeof(struct sw_flow_key));
1031         key_len = SW_FLOW_KEY_OFFSET(eth);
1032
1033         err = parse_flow_nlattrs(attr, a, &attrs);
1034         if (err)
1035                 return err;
1036
1037         /* Metadata attributes. */
1038         if (attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
1039                 swkey->phy.priority = nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]);
1040                 attrs &= ~(1 << OVS_KEY_ATTR_PRIORITY);
1041         }
1042         if (attrs & (1 << OVS_KEY_ATTR_IN_PORT)) {
1043                 u32 in_port = nla_get_u32(a[OVS_KEY_ATTR_IN_PORT]);
1044                 if (in_port >= DP_MAX_PORTS)
1045                         return -EINVAL;
1046                 swkey->phy.in_port = in_port;
1047                 attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
1048         } else {
1049                 swkey->phy.in_port = USHRT_MAX;
1050         }
1051
1052         if (attrs & (1ULL << OVS_KEY_ATTR_TUN_ID)) {
1053                 swkey->phy.tun_id = nla_get_be64(a[OVS_KEY_ATTR_TUN_ID]);
1054                 attrs &= ~(1ULL << OVS_KEY_ATTR_TUN_ID);
1055         }
1056
1057         /* Data attributes. */
1058         if (!(attrs & (1 << OVS_KEY_ATTR_ETHERNET)))
1059                 return -EINVAL;
1060         attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
1061
1062         eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
1063         memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
1064         memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
1065
1066         if (attrs & (1u << OVS_KEY_ATTR_ETHERTYPE) &&
1067             nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q)) {
1068                 const struct nlattr *encap;
1069                 __be16 tci;
1070
1071                 if (attrs != ((1 << OVS_KEY_ATTR_VLAN) |
1072                               (1 << OVS_KEY_ATTR_ETHERTYPE) |
1073                               (1 << OVS_KEY_ATTR_ENCAP)))
1074                         return -EINVAL;
1075
1076                 encap = a[OVS_KEY_ATTR_ENCAP];
1077                 tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
1078                 if (tci & htons(VLAN_TAG_PRESENT)) {
1079                         swkey->eth.tci = tci;
1080
1081                         err = parse_flow_nlattrs(encap, a, &attrs);
1082                         if (err)
1083                                 return err;
1084                 } else if (!tci) {
1085                         /* Corner case for truncated 802.1Q header. */
1086                         if (nla_len(encap))
1087                                 return -EINVAL;
1088
1089                         swkey->eth.type = htons(ETH_P_8021Q);
1090                         *key_lenp = key_len;
1091                         return 0;
1092                 } else {
1093                         return -EINVAL;
1094                 }
1095         }
1096
1097         if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
1098                 swkey->eth.type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
1099                 if (ntohs(swkey->eth.type) < 1536)
1100                         return -EINVAL;
1101                 attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
1102         } else {
1103                 swkey->eth.type = htons(ETH_P_802_2);
1104         }
1105
1106         if (swkey->eth.type == htons(ETH_P_IP)) {
1107                 const struct ovs_key_ipv4 *ipv4_key;
1108
1109                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV4)))
1110                         return -EINVAL;
1111                 attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
1112
1113                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
1114                 ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
1115                 if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
1116                         return -EINVAL;
1117                 swkey->ip.proto = ipv4_key->ipv4_proto;
1118                 swkey->ip.tos = ipv4_key->ipv4_tos;
1119                 swkey->ip.ttl = ipv4_key->ipv4_ttl;
1120                 swkey->ip.frag = ipv4_key->ipv4_frag;
1121                 swkey->ipv4.addr.src = ipv4_key->ipv4_src;
1122                 swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
1123
1124                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1125                         err = ipv4_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1126                         if (err)
1127                                 return err;
1128                 }
1129         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1130                 const struct ovs_key_ipv6 *ipv6_key;
1131
1132                 if (!(attrs & (1 << OVS_KEY_ATTR_IPV6)))
1133                         return -EINVAL;
1134                 attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
1135
1136                 key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
1137                 ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
1138                 if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
1139                         return -EINVAL;
1140                 swkey->ipv6.label = ipv6_key->ipv6_label;
1141                 swkey->ip.proto = ipv6_key->ipv6_proto;
1142                 swkey->ip.tos = ipv6_key->ipv6_tclass;
1143                 swkey->ip.ttl = ipv6_key->ipv6_hlimit;
1144                 swkey->ip.frag = ipv6_key->ipv6_frag;
1145                 memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
1146                        sizeof(swkey->ipv6.addr.src));
1147                 memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
1148                        sizeof(swkey->ipv6.addr.dst));
1149
1150                 if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1151                         err = ipv6_flow_from_nlattrs(swkey, &key_len, a, &attrs);
1152                         if (err)
1153                                 return err;
1154                 }
1155         } else if (swkey->eth.type == htons(ETH_P_ARP)) {
1156                 const struct ovs_key_arp *arp_key;
1157
1158                 if (!(attrs & (1 << OVS_KEY_ATTR_ARP)))
1159                         return -EINVAL;
1160                 attrs &= ~(1 << OVS_KEY_ATTR_ARP);
1161
1162                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
1163                 arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
1164                 swkey->ipv4.addr.src = arp_key->arp_sip;
1165                 swkey->ipv4.addr.dst = arp_key->arp_tip;
1166                 if (arp_key->arp_op & htons(0xff00))
1167                         return -EINVAL;
1168                 swkey->ip.proto = ntohs(arp_key->arp_op);
1169                 memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
1170                 memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
1171         }
1172
1173         if (attrs)
1174                 return -EINVAL;
1175         *key_lenp = key_len;
1176
1177         return 0;
1178 }
1179
1180 /**
1181  * ovs_flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
1182  * @in_port: receives the extracted input port.
1183  * @tun_id: receives the extracted tunnel ID.
1184  * @key: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1185  * sequence.
1186  *
1187  * This parses a series of Netlink attributes that form a flow key, which must
1188  * take the same form accepted by flow_from_nlattrs(), but only enough of it to
1189  * get the metadata, that is, the parts of the flow key that cannot be
1190  * extracted from the packet itself.
1191  */
1192 int ovs_flow_metadata_from_nlattrs(u32 *priority, u16 *in_port, __be64 *tun_id,
1193                                    const struct nlattr *attr)
1194 {
1195         const struct nlattr *nla;
1196         int rem;
1197
1198         *in_port = USHRT_MAX;
1199         *tun_id = 0;
1200         *priority = 0;
1201
1202         nla_for_each_nested(nla, attr, rem) {
1203                 int type = nla_type(nla);
1204
1205                 if (type <= OVS_KEY_ATTR_MAX && ovs_key_lens[type] > 0) {
1206                         if (nla_len(nla) != ovs_key_lens[type])
1207                                 return -EINVAL;
1208
1209                         switch (type) {
1210                         case OVS_KEY_ATTR_PRIORITY:
1211                                 *priority = nla_get_u32(nla);
1212                                 break;
1213
1214                         case OVS_KEY_ATTR_TUN_ID:
1215                                 *tun_id = nla_get_be64(nla);
1216                                 break;
1217
1218                         case OVS_KEY_ATTR_IN_PORT:
1219                                 if (nla_get_u32(nla) >= DP_MAX_PORTS)
1220                                         return -EINVAL;
1221                                 *in_port = nla_get_u32(nla);
1222                                 break;
1223                         }
1224                 }
1225         }
1226         if (rem)
1227                 return -EINVAL;
1228         return 0;
1229 }
1230
1231 int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
1232 {
1233         struct ovs_key_ethernet *eth_key;
1234         struct nlattr *nla, *encap;
1235
1236         if (swkey->phy.priority)
1237                 NLA_PUT_U32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority);
1238
1239         if (swkey->phy.tun_id != cpu_to_be64(0))
1240                 NLA_PUT_BE64(skb, OVS_KEY_ATTR_TUN_ID, swkey->phy.tun_id);
1241
1242         if (swkey->phy.in_port != USHRT_MAX)
1243                 NLA_PUT_U32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port);
1244
1245         nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
1246         if (!nla)
1247                 goto nla_put_failure;
1248         eth_key = nla_data(nla);
1249         memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
1250         memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
1251
1252         if (swkey->eth.tci || swkey->eth.type == htons(ETH_P_8021Q)) {
1253                 NLA_PUT_BE16(skb, OVS_KEY_ATTR_ETHERTYPE, htons(ETH_P_8021Q));
1254                 NLA_PUT_BE16(skb, OVS_KEY_ATTR_VLAN, swkey->eth.tci);
1255                 encap = nla_nest_start(skb, OVS_KEY_ATTR_ENCAP);
1256                 if (!swkey->eth.tci)
1257                         goto unencap;
1258         } else {
1259                 encap = NULL;
1260         }
1261
1262         if (swkey->eth.type == htons(ETH_P_802_2))
1263                 goto unencap;
1264
1265         NLA_PUT_BE16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type);
1266
1267         if (swkey->eth.type == htons(ETH_P_IP)) {
1268                 struct ovs_key_ipv4 *ipv4_key;
1269
1270                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
1271                 if (!nla)
1272                         goto nla_put_failure;
1273                 ipv4_key = nla_data(nla);
1274                 ipv4_key->ipv4_src = swkey->ipv4.addr.src;
1275                 ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
1276                 ipv4_key->ipv4_proto = swkey->ip.proto;
1277                 ipv4_key->ipv4_tos = swkey->ip.tos;
1278                 ipv4_key->ipv4_ttl = swkey->ip.ttl;
1279                 ipv4_key->ipv4_frag = swkey->ip.frag;
1280         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1281                 struct ovs_key_ipv6 *ipv6_key;
1282
1283                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
1284                 if (!nla)
1285                         goto nla_put_failure;
1286                 ipv6_key = nla_data(nla);
1287                 memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
1288                                 sizeof(ipv6_key->ipv6_src));
1289                 memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
1290                                 sizeof(ipv6_key->ipv6_dst));
1291                 ipv6_key->ipv6_label = swkey->ipv6.label;
1292                 ipv6_key->ipv6_proto = swkey->ip.proto;
1293                 ipv6_key->ipv6_tclass = swkey->ip.tos;
1294                 ipv6_key->ipv6_hlimit = swkey->ip.ttl;
1295                 ipv6_key->ipv6_frag = swkey->ip.frag;
1296         } else if (swkey->eth.type == htons(ETH_P_ARP)) {
1297                 struct ovs_key_arp *arp_key;
1298
1299                 nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
1300                 if (!nla)
1301                         goto nla_put_failure;
1302                 arp_key = nla_data(nla);
1303                 memset(arp_key, 0, sizeof(struct ovs_key_arp));
1304                 arp_key->arp_sip = swkey->ipv4.addr.src;
1305                 arp_key->arp_tip = swkey->ipv4.addr.dst;
1306                 arp_key->arp_op = htons(swkey->ip.proto);
1307                 memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1308                 memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1309         }
1310
1311         if ((swkey->eth.type == htons(ETH_P_IP) ||
1312              swkey->eth.type == htons(ETH_P_IPV6)) &&
1313              swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1314
1315                 if (swkey->ip.proto == IPPROTO_TCP) {
1316                         struct ovs_key_tcp *tcp_key;
1317
1318                         nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
1319                         if (!nla)
1320                                 goto nla_put_failure;
1321                         tcp_key = nla_data(nla);
1322                         if (swkey->eth.type == htons(ETH_P_IP)) {
1323                                 tcp_key->tcp_src = swkey->ipv4.tp.src;
1324                                 tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1325                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1326                                 tcp_key->tcp_src = swkey->ipv6.tp.src;
1327                                 tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1328                         }
1329                 } else if (swkey->ip.proto == IPPROTO_UDP) {
1330                         struct ovs_key_udp *udp_key;
1331
1332                         nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
1333                         if (!nla)
1334                                 goto nla_put_failure;
1335                         udp_key = nla_data(nla);
1336                         if (swkey->eth.type == htons(ETH_P_IP)) {
1337                                 udp_key->udp_src = swkey->ipv4.tp.src;
1338                                 udp_key->udp_dst = swkey->ipv4.tp.dst;
1339                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1340                                 udp_key->udp_src = swkey->ipv6.tp.src;
1341                                 udp_key->udp_dst = swkey->ipv6.tp.dst;
1342                         }
1343                 } else if (swkey->eth.type == htons(ETH_P_IP) &&
1344                            swkey->ip.proto == IPPROTO_ICMP) {
1345                         struct ovs_key_icmp *icmp_key;
1346
1347                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
1348                         if (!nla)
1349                                 goto nla_put_failure;
1350                         icmp_key = nla_data(nla);
1351                         icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1352                         icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1353                 } else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1354                            swkey->ip.proto == IPPROTO_ICMPV6) {
1355                         struct ovs_key_icmpv6 *icmpv6_key;
1356
1357                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
1358                                                 sizeof(*icmpv6_key));
1359                         if (!nla)
1360                                 goto nla_put_failure;
1361                         icmpv6_key = nla_data(nla);
1362                         icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1363                         icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1364
1365                         if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1366                             icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1367                                 struct ovs_key_nd *nd_key;
1368
1369                                 nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
1370                                 if (!nla)
1371                                         goto nla_put_failure;
1372                                 nd_key = nla_data(nla);
1373                                 memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1374                                                         sizeof(nd_key->nd_target));
1375                                 memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1376                                 memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1377                         }
1378                 }
1379         }
1380
1381 unencap:
1382         if (encap)
1383                 nla_nest_end(skb, encap);
1384
1385         return 0;
1386
1387 nla_put_failure:
1388         return -EMSGSIZE;
1389 }
1390
1391 /* Initializes the flow module.
1392  * Returns zero if successful or a negative error code. */
1393 int ovs_flow_init(void)
1394 {
1395         flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1396                                         0, NULL);
1397         if (flow_cache == NULL)
1398                 return -ENOMEM;
1399
1400         get_random_bytes(&hash_seed, sizeof(hash_seed));
1401
1402         return 0;
1403 }
1404
1405 /* Uninitializes the flow module. */
1406 void ovs_flow_exit(void)
1407 {
1408         kmem_cache_destroy(flow_cache);
1409 }