datapath/flow.c

   1 /*
   2  * Distributed under the terms of the GNU GPL version 2.
   3  * Copyright (c) 2007, 2008, 2009, 2010, 2011 Nicira Networks.
   4  *
   5  * Significant portions of this file may be copied from parts of the Linux
   6  * kernel, by Linus Torvalds and others.
   7  */
   8
   9 #include "flow.h"
  10 #include "datapath.h"
  11 #include <linux/uaccess.h>
  12 #include <linux/netdevice.h>
  13 #include <linux/etherdevice.h>
  14 #include <linux/if_ether.h>
  15 #include <linux/if_vlan.h>
  16 #include <net/llc_pdu.h>
  17 #include <linux/kernel.h>
  18 #include <linux/jhash.h>
  19 #include <linux/jiffies.h>
  20 #include <linux/llc.h>
  21 #include <linux/module.h>
  22 #include <linux/in.h>
  23 #include <linux/rcupdate.h>
  24 #include <linux/if_arp.h>
  25 #include <linux/if_ether.h>
  26 #include <linux/ip.h>
  27 #include <linux/ipv6.h>
  28 #include <linux/tcp.h>
  29 #include <linux/udp.h>
  30 #include <linux/icmp.h>
  31 #include <linux/icmpv6.h>
  32 #include <linux/rculist.h>
  33 #include <net/ip.h>
  34 #include <net/ipv6.h>
  35 #include <net/ndisc.h>
  36
  37 #include "vlan.h"
  38
  39 static struct kmem_cache *flow_cache;
  40 static unsigned int hash_seed __read_mostly;
  41
  42 static int check_header(struct sk_buff *skb, int len)
  43 {
  44         if (unlikely(skb->len < len))
  45                 return -EINVAL;
  46         if (unlikely(!pskb_may_pull(skb, len)))
  47                 return -ENOMEM;
  48         return 0;
  49 }
  50
  51 static bool arphdr_ok(struct sk_buff *skb)
  52 {
  53         return pskb_may_pull(skb, skb_network_offset(skb) +
  54                                   sizeof(struct arp_eth_header));
  55 }
  56
  57 static int check_iphdr(struct sk_buff *skb)
  58 {
  59         unsigned int nh_ofs = skb_network_offset(skb);
  60         unsigned int ip_len;
  61         int err;
  62
  63         err = check_header(skb, nh_ofs + sizeof(struct iphdr));
  64         if (unlikely(err))
  65                 return err;
  66
  67         ip_len = ip_hdrlen(skb);
  68         if (unlikely(ip_len < sizeof(struct iphdr) ||
  69                      skb->len < nh_ofs + ip_len))
  70                 return -EINVAL;
  71
  72         skb_set_transport_header(skb, nh_ofs + ip_len);
  73         return 0;
  74 }
  75
  76 static bool tcphdr_ok(struct sk_buff *skb)
  77 {
  78         int th_ofs = skb_transport_offset(skb);
  79         int tcp_len;
  80
  81         if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
  82                 return false;
  83
  84         tcp_len = tcp_hdrlen(skb);
  85         if (unlikely(tcp_len < sizeof(struct tcphdr) ||
  86                      skb->len < th_ofs + tcp_len))
  87                 return false;
  88
  89         return true;
  90 }
  91
  92 static bool udphdr_ok(struct sk_buff *skb)
  93 {
  94         return pskb_may_pull(skb, skb_transport_offset(skb) +
  95                                   sizeof(struct udphdr));
  96 }
  97
  98 static bool icmphdr_ok(struct sk_buff *skb)
  99 {
 100         return pskb_may_pull(skb, skb_transport_offset(skb) +
 101                                   sizeof(struct icmphdr));
 102 }
 103
 104 u64 flow_used_time(unsigned long flow_jiffies)
 105 {
 106         struct timespec cur_ts;
 107         u64 cur_ms, idle_ms;
 108
 109         ktime_get_ts(&cur_ts);
 110         idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
 111         cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
 112                  cur_ts.tv_nsec / NSEC_PER_MSEC;
 113
 114         return cur_ms - idle_ms;
 115 }
 116
 117 #define SW_FLOW_KEY_OFFSET(field)               \
 118         (offsetof(struct sw_flow_key, field) +  \
 119          FIELD_SIZEOF(struct sw_flow_key, field))
 120
 121 /**
 122  * skip_exthdr - skip any IPv6 extension headers
 123  * @skb: skbuff to parse
 124  * @start: offset of first extension header
 125  * @nexthdrp: Initially, points to the type of the extension header at @start.
 126  * This function updates it to point to the extension header at the final
 127  * offset.
 128  * @frag: Points to the @frag member in a &struct sw_flow_key.  This
 129  * function sets an appropriate %OVS_FRAG_TYPE_* value.
 130  *
 131  * This is based on ipv6_skip_exthdr() but adds the updates to *@frag.
 132  *
 133  * When there is more than one fragment header, this version reports whether
 134  * the final fragment header that it examines is a first fragment.
 135  *
 136  * Returns the final payload offset, or -1 on error.
 137  */
 138 static int skip_exthdr(const struct sk_buff *skb, int start, u8 *nexthdrp,
 139                        u8 *frag)
 140 {
 141         u8 nexthdr = *nexthdrp;
 142
 143         while (ipv6_ext_hdr(nexthdr)) {
 144                 struct ipv6_opt_hdr _hdr, *hp;
 145                 int hdrlen;
 146
 147                 if (nexthdr == NEXTHDR_NONE)
 148                         return -1;
 149                 hp = skb_header_pointer(skb, start, sizeof(_hdr), &_hdr);
 150                 if (hp == NULL)
 151                         return -1;
 152                 if (nexthdr == NEXTHDR_FRAGMENT) {
 153                         __be16 _frag_off, *fp;
 154                         fp = skb_header_pointer(skb,
 155                                                 start+offsetof(struct frag_hdr,
 156                                                                frag_off),
 157                                                 sizeof(_frag_off),
 158                                                 &_frag_off);
 159                         if (fp == NULL)
 160                                 return -1;
 161
 162                         if (ntohs(*fp) & ~0x7) {
 163                                 *frag = OVS_FRAG_TYPE_LATER;
 164                                 break;
 165                         }
 166                         *frag = OVS_FRAG_TYPE_FIRST;
 167                         hdrlen = 8;
 168                 } else if (nexthdr == NEXTHDR_AUTH)
 169                         hdrlen = (hp->hdrlen+2)<<2;
 170                 else
 171                         hdrlen = ipv6_optlen(hp);
 172
 173                 nexthdr = hp->nexthdr;
 174                 start += hdrlen;
 175         }
 176
 177         *nexthdrp = nexthdr;
 178         return start;
 179 }
 180
 181 static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key,
 182                          int *key_lenp)
 183 {
 184         unsigned int nh_ofs = skb_network_offset(skb);
 185         unsigned int nh_len;
 186         int payload_ofs;
 187         struct ipv6hdr *nh;
 188         uint8_t nexthdr;
 189         int err;
 190
 191         *key_lenp = SW_FLOW_KEY_OFFSET(ipv6.label);
 192
 193         err = check_header(skb, nh_ofs + sizeof(*nh));
 194         if (unlikely(err))
 195                 return err;
 196
 197         nh = ipv6_hdr(skb);
 198         nexthdr = nh->nexthdr;
 199         payload_ofs = (u8 *)(nh + 1) - skb->data;
 200
 201         key->ip.proto = NEXTHDR_NONE;
 202         key->ip.tos = ipv6_get_dsfield(nh);
 203         key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
 204         ipv6_addr_copy(&key->ipv6.addr.src, &nh->saddr);
 205         ipv6_addr_copy(&key->ipv6.addr.dst, &nh->daddr);
 206
 207         payload_ofs = skip_exthdr(skb, payload_ofs, &nexthdr, &key->ip.frag);
 208         if (unlikely(payload_ofs < 0))
 209                 return -EINVAL;
 210
 211         nh_len = payload_ofs - nh_ofs;
 212         skb_set_transport_header(skb, nh_ofs + nh_len);
 213         key->ip.proto = nexthdr;
 214         return nh_len;
 215 }
 216
 217 static bool icmp6hdr_ok(struct sk_buff *skb)
 218 {
 219         return pskb_may_pull(skb, skb_transport_offset(skb) +
 220                                   sizeof(struct icmp6hdr));
 221 }
 222
 223 #define TCP_FLAGS_OFFSET 13
 224 #define TCP_FLAG_MASK 0x3f
 225
 226 void flow_used(struct sw_flow *flow, struct sk_buff *skb)
 227 {
 228         u8 tcp_flags = 0;
 229
 230         if (flow->key.eth.type == htons(ETH_P_IP) &&
 231             flow->key.ip.proto == IPPROTO_TCP) {
 232                 u8 *tcp = (u8 *)tcp_hdr(skb);
 233                 tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
 234         }
 235
 236         spin_lock(&flow->lock);
 237         flow->used = jiffies;
 238         flow->packet_count++;
 239         flow->byte_count += skb->len;
 240         flow->tcp_flags |= tcp_flags;
 241         spin_unlock(&flow->lock);
 242 }
 243
 244 struct sw_flow_actions *flow_actions_alloc(const struct nlattr *actions)
 245 {
 246         int actions_len = nla_len(actions);
 247         struct sw_flow_actions *sfa;
 248
 249         /* At least DP_MAX_PORTS actions are required to be able to flood a
 250          * packet to every port.  Factor of 2 allows for setting VLAN tags,
 251          * etc. */
 252         if (actions_len > 2 * DP_MAX_PORTS * nla_total_size(4))
 253                 return ERR_PTR(-EINVAL);
 254
 255         sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
 256         if (!sfa)
 257                 return ERR_PTR(-ENOMEM);
 258
 259         sfa->actions_len = actions_len;
 260         memcpy(sfa->actions, nla_data(actions), actions_len);
 261         return sfa;
 262 }
 263
 264 struct sw_flow *flow_alloc(void)
 265 {
 266         struct sw_flow *flow;
 267
 268         flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
 269         if (!flow)
 270                 return ERR_PTR(-ENOMEM);
 271
 272         spin_lock_init(&flow->lock);
 273         atomic_set(&flow->refcnt, 1);
 274         flow->sf_acts = NULL;
 275         flow->dead = false;
 276
 277         return flow;
 278 }
 279
 280 static struct hlist_head __rcu *find_bucket(struct flow_table * table, u32 hash)
 281 {
 282         return flex_array_get(table->buckets,
 283                                 (hash & (table->n_buckets - 1)));
 284 }
 285
 286 static struct flex_array  __rcu *alloc_buckets(unsigned int n_buckets)
 287 {
 288         struct flex_array  __rcu *buckets;
 289         int i, err;
 290
 291         buckets = flex_array_alloc(sizeof(struct hlist_head *),
 292                                    n_buckets, GFP_KERNEL);
 293         if (!buckets)
 294                 return NULL;
 295
 296         err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
 297         if (err) {
 298                 flex_array_free(buckets);
 299                 return NULL;
 300         }
 301
 302         for (i = 0; i < n_buckets; i++)
 303                 INIT_HLIST_HEAD((struct hlist_head *)
 304                                         flex_array_get(buckets, i));
 305
 306         return buckets;
 307 }
 308
 309 static void free_buckets(struct flex_array *buckets)
 310 {
 311         flex_array_free(buckets);
 312 }
 313
 314 struct flow_table *flow_tbl_alloc(int new_size)
 315 {
 316         struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
 317
 318         if (!table)
 319                 return NULL;
 320
 321         table->buckets = alloc_buckets(new_size);
 322
 323         if (!table->buckets) {
 324                 kfree(table);
 325                 return NULL;
 326         }
 327         table->n_buckets = new_size;
 328         table->count = 0;
 329
 330         return table;
 331 }
 332
 333 static void flow_free(struct sw_flow *flow)
 334 {
 335         flow->dead = true;
 336         flow_put(flow);
 337 }
 338
 339 void flow_tbl_destroy(struct flow_table *table)
 340 {
 341         int i;
 342
 343         if (!table)
 344                 return;
 345
 346         for (i = 0; i < table->n_buckets; i++) {
 347                 struct sw_flow *flow;
 348                 struct hlist_head *head = flex_array_get(table->buckets, i);
 349                 struct hlist_node *node, *n;
 350
 351                 hlist_for_each_entry_safe(flow, node, n, head, hash_node) {
 352                         hlist_del_init_rcu(&flow->hash_node);
 353                         flow_free(flow);
 354                 }
 355         }
 356
 357         free_buckets(table->buckets);
 358         kfree(table);
 359 }
 360
 361 static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
 362 {
 363         struct flow_table *table = container_of(rcu, struct flow_table, rcu);
 364
 365         flow_tbl_destroy(table);
 366 }
 367
 368 void flow_tbl_deferred_destroy(struct flow_table *table)
 369 {
 370         if (!table)
 371                 return;
 372
 373         call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
 374 }
 375
 376 struct sw_flow *flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
 377 {
 378         struct sw_flow *flow;
 379         struct hlist_head *head;
 380         struct hlist_node *n;
 381         int i;
 382
 383         while (*bucket < table->n_buckets) {
 384                 i = 0;
 385                 head = flex_array_get(table->buckets, *bucket);
 386                 hlist_for_each_entry_rcu(flow, n, head, hash_node) {
 387                         if (i < *last) {
 388                                 i++;
 389                                 continue;
 390                         }
 391                         *last = i + 1;
 392                         return flow;
 393                 }
 394                 (*bucket)++;
 395                 *last = 0;
 396         }
 397
 398         return NULL;
 399 }
 400
 401 struct flow_table *flow_tbl_expand(struct flow_table *table)
 402 {
 403         struct flow_table *new_table;
 404         int n_buckets = table->n_buckets * 2;
 405         int i;
 406
 407         new_table = flow_tbl_alloc(n_buckets);
 408         if (!new_table)
 409                 return ERR_PTR(-ENOMEM);
 410
 411         for (i = 0; i < table->n_buckets; i++) {
 412                 struct sw_flow *flow;
 413                 struct hlist_head *head;
 414                 struct hlist_node *n, *pos;
 415
 416                 head = flex_array_get(table->buckets, i);
 417
 418                 hlist_for_each_entry_safe(flow, n, pos, head, hash_node) {
 419                         hlist_del_init_rcu(&flow->hash_node);
 420                         flow_tbl_insert(new_table, flow);
 421                 }
 422         }
 423
 424         return new_table;
 425 }
 426
 427 /* RCU callback used by flow_deferred_free. */
 428 static void rcu_free_flow_callback(struct rcu_head *rcu)
 429 {
 430         struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
 431
 432         flow->dead = true;
 433         flow_put(flow);
 434 }
 435
 436 /* Schedules 'flow' to be freed after the next RCU grace period.
 437  * The caller must hold rcu_read_lock for this to be sensible. */
 438 void flow_deferred_free(struct sw_flow *flow)
 439 {
 440         call_rcu(&flow->rcu, rcu_free_flow_callback);
 441 }
 442
 443 void flow_hold(struct sw_flow *flow)
 444 {
 445         atomic_inc(&flow->refcnt);
 446 }
 447
 448 void flow_put(struct sw_flow *flow)
 449 {
 450         if (unlikely(!flow))
 451                 return;
 452
 453         if (atomic_dec_and_test(&flow->refcnt)) {
 454                 kfree((struct sf_flow_acts __force *)flow->sf_acts);
 455                 kmem_cache_free(flow_cache, flow);
 456         }
 457 }
 458
 459 /* RCU callback used by flow_deferred_free_acts. */
 460 static void rcu_free_acts_callback(struct rcu_head *rcu)
 461 {
 462         struct sw_flow_actions *sf_acts = container_of(rcu,
 463                         struct sw_flow_actions, rcu);
 464         kfree(sf_acts);
 465 }
 466
 467 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
 468  * The caller must hold rcu_read_lock for this to be sensible. */
 469 void flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
 470 {
 471         call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
 472 }
 473
 474 static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 475 {
 476         struct qtag_prefix {
 477                 __be16 eth_type; /* ETH_P_8021Q */
 478                 __be16 tci;
 479         };
 480         struct qtag_prefix *qp;
 481
 482         if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
 483                                          sizeof(__be16))))
 484                 return -ENOMEM;
 485
 486         qp = (struct qtag_prefix *) skb->data;
 487         key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
 488         __skb_pull(skb, sizeof(struct qtag_prefix));
 489
 490         return 0;
 491 }
 492
 493 static __be16 parse_ethertype(struct sk_buff *skb)
 494 {
 495         struct llc_snap_hdr {
 496                 u8  dsap;  /* Always 0xAA */
 497                 u8  ssap;  /* Always 0xAA */
 498                 u8  ctrl;
 499                 u8  oui[3];
 500                 __be16 ethertype;
 501         };
 502         struct llc_snap_hdr *llc;
 503         __be16 proto;
 504
 505         proto = *(__be16 *) skb->data;
 506         __skb_pull(skb, sizeof(__be16));
 507
 508         if (ntohs(proto) >= 1536)
 509                 return proto;
 510
 511         if (skb->len < sizeof(struct llc_snap_hdr))
 512                 return htons(ETH_P_802_2);
 513
 514         if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
 515                 return htons(0);
 516
 517         llc = (struct llc_snap_hdr *) skb->data;
 518         if (llc->dsap != LLC_SAP_SNAP ||
 519             llc->ssap != LLC_SAP_SNAP ||
 520             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
 521                 return htons(ETH_P_802_2);
 522
 523         __skb_pull(skb, sizeof(struct llc_snap_hdr));
 524         return llc->ethertype;
 525 }
 526
 527 static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
 528                         int *key_lenp, int nh_len)
 529 {
 530         struct icmp6hdr *icmp = icmp6_hdr(skb);
 531         int error = 0;
 532         int key_len;
 533
 534         /* The ICMPv6 type and code fields use the 16-bit transport port
 535          * fields, so we need to store them in 16-bit network byte order.
 536          */
 537         key->ipv6.tp.src = htons(icmp->icmp6_type);
 538         key->ipv6.tp.dst = htons(icmp->icmp6_code);
 539         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 540
 541         if (icmp->icmp6_code == 0 &&
 542             (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
 543              icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
 544                 int icmp_len = skb->len - skb_transport_offset(skb);
 545                 struct nd_msg *nd;
 546                 int offset;
 547
 548                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 549
 550                 /* In order to process neighbor discovery options, we need the
 551                  * entire packet.
 552                  */
 553                 if (unlikely(icmp_len < sizeof(*nd)))
 554                         goto out;
 555                 if (unlikely(skb_linearize(skb))) {
 556                         error = -ENOMEM;
 557                         goto out;
 558                 }
 559
 560                 nd = (struct nd_msg *)skb_transport_header(skb);
 561                 ipv6_addr_copy(&key->ipv6.nd.target, &nd->target);
 562                 key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
 563
 564                 icmp_len -= sizeof(*nd);
 565                 offset = 0;
 566                 while (icmp_len >= 8) {
 567                         struct nd_opt_hdr *nd_opt =
 568                                  (struct nd_opt_hdr *)(nd->opt + offset);
 569                         int opt_len = nd_opt->nd_opt_len * 8;
 570
 571                         if (unlikely(!opt_len || opt_len > icmp_len))
 572                                 goto invalid;
 573
 574                         /* Store the link layer address if the appropriate
 575                          * option is provided.  It is considered an error if
 576                          * the same link layer option is specified twice.
 577                          */
 578                         if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
 579                             && opt_len == 8) {
 580                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
 581                                         goto invalid;
 582                                 memcpy(key->ipv6.nd.sll,
 583                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 584                         } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
 585                                    && opt_len == 8) {
 586                                 if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
 587                                         goto invalid;
 588                                 memcpy(key->ipv6.nd.tll,
 589                                     &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
 590                         }
 591
 592                         icmp_len -= opt_len;
 593                         offset += opt_len;
 594                 }
 595         }
 596
 597         goto out;
 598
 599 invalid:
 600         memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
 601         memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
 602         memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
 603
 604 out:
 605         *key_lenp = key_len;
 606         return error;
 607 }
 608
 609 /**
 610  * flow_extract - extracts a flow key from an Ethernet frame.
 611  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 612  * Ethernet header
 613  * @in_port: port number on which @skb was received.
 614  * @key: output flow key
 615  * @key_lenp: length of output flow key
 616  *
 617  * The caller must ensure that skb->len >= ETH_HLEN.
 618  *
 619  * Returns 0 if successful, otherwise a negative errno value.
 620  *
 621  * Initializes @skb header pointers as follows:
 622  *
 623  *    - skb->mac_header: the Ethernet header.
 624  *
 625  *    - skb->network_header: just past the Ethernet header, or just past the
 626  *      VLAN header, to the first byte of the Ethernet payload.
 627  *
 628  *    - skb->transport_header: If key->dl_type is ETH_P_IP or ETH_P_IPV6
 629  *      on output, then just past the IP header, if one is present and
 630  *      of a correct length, otherwise the same as skb->network_header.
 631  *      For other key->dl_type values it is left untouched.
 632  */
 633 int flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
 634                  int *key_lenp)
 635 {
 636         int error = 0;
 637         int key_len = SW_FLOW_KEY_OFFSET(eth);
 638         struct ethhdr *eth;
 639
 640         memset(key, 0, sizeof(*key));
 641
 642         key->phy.priority = skb->priority;
 643         key->phy.tun_id = OVS_CB(skb)->tun_id;
 644         key->phy.in_port = in_port;
 645
 646         skb_reset_mac_header(skb);
 647
 648         /* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
 649          * header in the linear data area.
 650          */
 651         eth = eth_hdr(skb);
 652         memcpy(key->eth.src, eth->h_source, ETH_ALEN);
 653         memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
 654
 655         __skb_pull(skb, 2 * ETH_ALEN);
 656
 657         if (vlan_tx_tag_present(skb))
 658                 key->eth.tci = htons(vlan_get_tci(skb));
 659         else if (eth->h_proto == htons(ETH_P_8021Q))
 660                 if (unlikely(parse_vlan(skb, key)))
 661                         return -ENOMEM;
 662
 663         key->eth.type = parse_ethertype(skb);
 664         if (unlikely(key->eth.type == htons(0)))
 665                 return -ENOMEM;
 666
 667         skb_reset_network_header(skb);
 668         __skb_push(skb, skb->data - skb_mac_header(skb));
 669
 670         /* Network layer. */
 671         if (key->eth.type == htons(ETH_P_IP)) {
 672                 struct iphdr *nh;
 673                 __be16 offset;
 674
 675                 key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
 676
 677                 error = check_iphdr(skb);
 678                 if (unlikely(error)) {
 679                         if (error == -EINVAL) {
 680                                 skb->transport_header = skb->network_header;
 681                                 error = 0;
 682                         }
 683                         goto out;
 684                 }
 685
 686                 nh = ip_hdr(skb);
 687                 key->ipv4.addr.src = nh->saddr;
 688                 key->ipv4.addr.dst = nh->daddr;
 689
 690                 key->ip.proto = nh->protocol;
 691                 key->ip.tos = nh->tos;
 692
 693                 offset = nh->frag_off & htons(IP_OFFSET);
 694                 if (offset) {
 695                         key->ip.frag = OVS_FRAG_TYPE_LATER;
 696                         goto out;
 697                 }
 698                 if (nh->frag_off & htons(IP_MF) ||
 699                          skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 700                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 701
 702                 /* Transport layer. */
 703                 if (key->ip.proto == IPPROTO_TCP) {
 704                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 705                         if (tcphdr_ok(skb)) {
 706                                 struct tcphdr *tcp = tcp_hdr(skb);
 707                                 key->ipv4.tp.src = tcp->source;
 708                                 key->ipv4.tp.dst = tcp->dest;
 709                         }
 710                 } else if (key->ip.proto == IPPROTO_UDP) {
 711                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 712                         if (udphdr_ok(skb)) {
 713                                 struct udphdr *udp = udp_hdr(skb);
 714                                 key->ipv4.tp.src = udp->source;
 715                                 key->ipv4.tp.dst = udp->dest;
 716                         }
 717                 } else if (key->ip.proto == IPPROTO_ICMP) {
 718                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 719                         if (icmphdr_ok(skb)) {
 720                                 struct icmphdr *icmp = icmp_hdr(skb);
 721                                 /* The ICMP type and code fields use the 16-bit
 722                                  * transport port fields, so we need to store
 723                                  * them in 16-bit network byte order. */
 724                                 key->ipv4.tp.src = htons(icmp->type);
 725                                 key->ipv4.tp.dst = htons(icmp->code);
 726                         }
 727                 }
 728
 729         } else if (key->eth.type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
 730                 struct arp_eth_header *arp;
 731
 732                 arp = (struct arp_eth_header *)skb_network_header(skb);
 733
 734                 if (arp->ar_hrd == htons(ARPHRD_ETHER)
 735                                 && arp->ar_pro == htons(ETH_P_IP)
 736                                 && arp->ar_hln == ETH_ALEN
 737                                 && arp->ar_pln == 4) {
 738
 739                         /* We only match on the lower 8 bits of the opcode. */
 740                         if (ntohs(arp->ar_op) <= 0xff)
 741                                 key->ip.proto = ntohs(arp->ar_op);
 742
 743                         if (key->ip.proto == ARPOP_REQUEST
 744                                         || key->ip.proto == ARPOP_REPLY) {
 745                                 memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
 746                                 memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
 747                                 memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
 748                                 memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
 749                                 key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
 750                         }
 751                 }
 752         } else if (key->eth.type == htons(ETH_P_IPV6)) {
 753                 int nh_len;             /* IPv6 Header + Extensions */
 754
 755                 nh_len = parse_ipv6hdr(skb, key, &key_len);
 756                 if (unlikely(nh_len < 0)) {
 757                         if (nh_len == -EINVAL)
 758                                 skb->transport_header = skb->network_header;
 759                         else
 760                                 error = nh_len;
 761                         goto out;
 762                 }
 763
 764                 if (key->ip.frag == OVS_FRAG_TYPE_LATER)
 765                         goto out;
 766                 if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
 767                         key->ip.frag = OVS_FRAG_TYPE_FIRST;
 768
 769                 /* Transport layer. */
 770                 if (key->ip.proto == NEXTHDR_TCP) {
 771                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 772                         if (tcphdr_ok(skb)) {
 773                                 struct tcphdr *tcp = tcp_hdr(skb);
 774                                 key->ipv6.tp.src = tcp->source;
 775                                 key->ipv6.tp.dst = tcp->dest;
 776                         }
 777                 } else if (key->ip.proto == NEXTHDR_UDP) {
 778                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 779                         if (udphdr_ok(skb)) {
 780                                 struct udphdr *udp = udp_hdr(skb);
 781                                 key->ipv6.tp.src = udp->source;
 782                                 key->ipv6.tp.dst = udp->dest;
 783                         }
 784                 } else if (key->ip.proto == NEXTHDR_ICMP) {
 785                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 786                         if (icmp6hdr_ok(skb)) {
 787                                 error = parse_icmpv6(skb, key, &key_len, nh_len);
 788                                 if (error < 0)
 789                                         goto out;
 790                         }
 791                 }
 792         }
 793
 794 out:
 795         *key_lenp = key_len;
 796         return error;
 797 }
 798
 799 u32 flow_hash(const struct sw_flow_key *key, int key_len)
 800 {
 801         return jhash2((u32 *)key, DIV_ROUND_UP(key_len, sizeof(u32)), hash_seed);
 802 }
 803
 804 struct sw_flow *flow_tbl_lookup(struct flow_table *table,
 805                                 struct sw_flow_key *key, int key_len)
 806 {
 807         struct sw_flow *flow;
 808         struct hlist_node *n;
 809         struct hlist_head *head;
 810         u32 hash;
 811
 812         hash = flow_hash(key, key_len);
 813
 814         head = find_bucket(table, hash);
 815         hlist_for_each_entry_rcu(flow, n, head, hash_node) {
 816
 817                 if (flow->hash == hash &&
 818                     !memcmp(&flow->key, key, key_len)) {
 819                         return flow;
 820                 }
 821         }
 822         return NULL;
 823 }
 824
 825 void flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
 826 {
 827         struct hlist_head *head;
 828
 829         head = find_bucket(table, flow->hash);
 830         hlist_add_head_rcu(&flow->hash_node, head);
 831         table->count++;
 832 }
 833
 834 void flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
 835 {
 836         if (!hlist_unhashed(&flow->hash_node)) {
 837                 hlist_del_init_rcu(&flow->hash_node);
 838                 table->count--;
 839                 BUG_ON(table->count < 0);
 840         }
 841 }
 842
 843 /* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
 844 const u32 ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
 845         [OVS_KEY_ATTR_PRIORITY] = 4,
 846         [OVS_KEY_ATTR_TUN_ID] = 8,
 847         [OVS_KEY_ATTR_IN_PORT] = 4,
 848         [OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
 849         [OVS_KEY_ATTR_8021Q] = sizeof(struct ovs_key_8021q),
 850         [OVS_KEY_ATTR_ETHERTYPE] = 2,
 851         [OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
 852         [OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
 853         [OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
 854         [OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
 855         [OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
 856         [OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
 857         [OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
 858         [OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
 859 };
 860
 861 /**
 862  * flow_from_nlattrs - parses Netlink attributes into a flow key.
 863  * @swkey: receives the extracted flow key.
 864  * @key_lenp: number of bytes used in @swkey.
 865  * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
 866  * sequence.
 867  *
 868  * This state machine accepts the following forms, with [] for optional
 869  * elements and | for alternatives:
 870  *
 871  * [priority] [tun_id] [in_port] ethernet [8021q] [ethertype \
 872  *              [IPv4 [TCP|UDP|ICMP] | IPv6 [TCP|UDP|ICMPv6 [ND]] | ARP]]
 873  *
 874  * except that IPv4 or IPv6 terminates the sequence if its @ipv4_frag or
 875  * @ipv6_frag member, respectively, equals %OVS_FRAG_TYPE_LATER.
 876  */
 877 int flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
 878                       const struct nlattr *attr)
 879 {
 880         int error = 0;
 881         const struct nlattr *nla;
 882         u16 prev_type;
 883         int rem;
 884         int key_len;
 885
 886         memset(swkey, 0, sizeof(*swkey));
 887         swkey->phy.in_port = USHRT_MAX;
 888         swkey->eth.type = htons(ETH_P_802_2);
 889         key_len = SW_FLOW_KEY_OFFSET(eth);
 890
 891         prev_type = OVS_KEY_ATTR_UNSPEC;
 892         nla_for_each_nested(nla, attr, rem) {
 893                 const struct ovs_key_ethernet *eth_key;
 894                 const struct ovs_key_8021q *q_key;
 895                 const struct ovs_key_ipv4 *ipv4_key;
 896                 const struct ovs_key_ipv6 *ipv6_key;
 897                 const struct ovs_key_tcp *tcp_key;
 898                 const struct ovs_key_udp *udp_key;
 899                 const struct ovs_key_icmp *icmp_key;
 900                 const struct ovs_key_icmpv6 *icmpv6_key;
 901                 const struct ovs_key_arp *arp_key;
 902                 const struct ovs_key_nd *nd_key;
 903
 904                 int type = nla_type(nla);
 905
 906                 if (type > OVS_KEY_ATTR_MAX ||
 907                     nla_len(nla) != ovs_key_lens[type])
 908                         goto invalid;
 909
 910 #define TRANSITION(PREV_TYPE, TYPE) (((PREV_TYPE) << 16) | (TYPE))
 911                 switch (TRANSITION(prev_type, type)) {
 912                 case TRANSITION(OVS_KEY_ATTR_UNSPEC, OVS_KEY_ATTR_PRIORITY):
 913                         swkey->phy.priority = nla_get_u32(nla);
 914                         break;
 915
 916                 case TRANSITION(OVS_KEY_ATTR_UNSPEC, OVS_KEY_ATTR_TUN_ID):
 917                 case TRANSITION(OVS_KEY_ATTR_PRIORITY, OVS_KEY_ATTR_TUN_ID):
 918                         swkey->phy.tun_id = nla_get_be64(nla);
 919                         break;
 920
 921                 case TRANSITION(OVS_KEY_ATTR_UNSPEC, OVS_KEY_ATTR_IN_PORT):
 922                 case TRANSITION(OVS_KEY_ATTR_PRIORITY, OVS_KEY_ATTR_IN_PORT):
 923                 case TRANSITION(OVS_KEY_ATTR_TUN_ID, OVS_KEY_ATTR_IN_PORT):
 924                         if (nla_get_u32(nla) >= DP_MAX_PORTS)
 925                                 goto invalid;
 926                         swkey->phy.in_port = nla_get_u32(nla);
 927                         break;
 928
 929                 case TRANSITION(OVS_KEY_ATTR_UNSPEC, OVS_KEY_ATTR_ETHERNET):
 930                 case TRANSITION(OVS_KEY_ATTR_PRIORITY, OVS_KEY_ATTR_ETHERNET):
 931                 case TRANSITION(OVS_KEY_ATTR_TUN_ID, OVS_KEY_ATTR_ETHERNET):
 932                 case TRANSITION(OVS_KEY_ATTR_IN_PORT, OVS_KEY_ATTR_ETHERNET):
 933                         eth_key = nla_data(nla);
 934                         memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
 935                         memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
 936                         break;
 937
 938                 case TRANSITION(OVS_KEY_ATTR_ETHERNET, OVS_KEY_ATTR_8021Q):
 939                         q_key = nla_data(nla);
 940                         /* Only standard 0x8100 VLANs currently supported. */
 941                         if (q_key->q_tpid != htons(ETH_P_8021Q))
 942                                 goto invalid;
 943                         if (q_key->q_tci & htons(VLAN_TAG_PRESENT))
 944                                 goto invalid;
 945                         swkey->eth.tci = q_key->q_tci | htons(VLAN_TAG_PRESENT);
 946                         break;
 947
 948                 case TRANSITION(OVS_KEY_ATTR_8021Q, OVS_KEY_ATTR_ETHERTYPE):
 949                 case TRANSITION(OVS_KEY_ATTR_ETHERNET, OVS_KEY_ATTR_ETHERTYPE):
 950                         swkey->eth.type = nla_get_be16(nla);
 951                         if (ntohs(swkey->eth.type) < 1536)
 952                                 goto invalid;
 953                         break;
 954
 955                 case TRANSITION(OVS_KEY_ATTR_ETHERTYPE, OVS_KEY_ATTR_IPV4):
 956                         key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
 957                         if (swkey->eth.type != htons(ETH_P_IP))
 958                                 goto invalid;
 959                         ipv4_key = nla_data(nla);
 960                         if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
 961                                 goto invalid;
 962                         swkey->ip.proto = ipv4_key->ipv4_proto;
 963                         swkey->ip.tos = ipv4_key->ipv4_tos;
 964                         swkey->ip.frag = ipv4_key->ipv4_frag;
 965                         swkey->ipv4.addr.src = ipv4_key->ipv4_src;
 966                         swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
 967                         break;
 968
 969                 case TRANSITION(OVS_KEY_ATTR_ETHERTYPE, OVS_KEY_ATTR_IPV6):
 970                         key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
 971                         if (swkey->eth.type != htons(ETH_P_IPV6))
 972                                 goto invalid;
 973                         ipv6_key = nla_data(nla);
 974                         if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
 975                                 goto invalid;
 976                         swkey->ipv6.label = ipv6_key->ipv6_label;
 977                         swkey->ip.proto = ipv6_key->ipv6_proto;
 978                         swkey->ip.tos = ipv6_key->ipv6_tos;
 979                         swkey->ip.frag = ipv6_key->ipv6_frag;
 980                         memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
 981                                         sizeof(swkey->ipv6.addr.src));
 982                         memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
 983                                         sizeof(swkey->ipv6.addr.dst));
 984                         break;
 985
 986                 case TRANSITION(OVS_KEY_ATTR_IPV4, OVS_KEY_ATTR_TCP):
 987                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
 988                         if (swkey->ip.proto != IPPROTO_TCP)
 989                                 goto invalid;
 990                         tcp_key = nla_data(nla);
 991                         swkey->ipv4.tp.src = tcp_key->tcp_src;
 992                         swkey->ipv4.tp.dst = tcp_key->tcp_dst;
 993                         break;
 994
 995                 case TRANSITION(OVS_KEY_ATTR_IPV6, OVS_KEY_ATTR_TCP):
 996                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
 997                         if (swkey->ip.proto != IPPROTO_TCP)
 998                                 goto invalid;
 999                         tcp_key = nla_data(nla);
1000                         swkey->ipv6.tp.src = tcp_key->tcp_src;
1001                         swkey->ipv6.tp.dst = tcp_key->tcp_dst;
1002                         break;
1003
1004                 case TRANSITION(OVS_KEY_ATTR_IPV4, OVS_KEY_ATTR_UDP):
1005                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
1006                         if (swkey->ip.proto != IPPROTO_UDP)
1007                                 goto invalid;
1008                         udp_key = nla_data(nla);
1009                         swkey->ipv4.tp.src = udp_key->udp_src;
1010                         swkey->ipv4.tp.dst = udp_key->udp_dst;
1011                         break;
1012
1013                 case TRANSITION(OVS_KEY_ATTR_IPV6, OVS_KEY_ATTR_UDP):
1014                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
1015                         if (swkey->ip.proto != IPPROTO_UDP)
1016                                 goto invalid;
1017                         udp_key = nla_data(nla);
1018                         swkey->ipv6.tp.src = udp_key->udp_src;
1019                         swkey->ipv6.tp.dst = udp_key->udp_dst;
1020                         break;
1021
1022                 case TRANSITION(OVS_KEY_ATTR_IPV4, OVS_KEY_ATTR_ICMP):
1023                         key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
1024                         if (swkey->ip.proto != IPPROTO_ICMP)
1025                                 goto invalid;
1026                         icmp_key = nla_data(nla);
1027                         swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
1028                         swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
1029                         break;
1030
1031                 case TRANSITION(OVS_KEY_ATTR_IPV6, OVS_KEY_ATTR_ICMPV6):
1032                         key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
1033                         if (swkey->ip.proto != IPPROTO_ICMPV6)
1034                                 goto invalid;
1035                         icmpv6_key = nla_data(nla);
1036                         swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
1037                         swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
1038                         break;
1039
1040                 case TRANSITION(OVS_KEY_ATTR_ETHERTYPE, OVS_KEY_ATTR_ARP):
1041                         key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
1042                         if (swkey->eth.type != htons(ETH_P_ARP))
1043                                 goto invalid;
1044                         arp_key = nla_data(nla);
1045                         swkey->ipv4.addr.src = arp_key->arp_sip;
1046                         swkey->ipv4.addr.dst = arp_key->arp_tip;
1047                         if (arp_key->arp_op & htons(0xff00))
1048                                 goto invalid;
1049                         swkey->ip.proto = ntohs(arp_key->arp_op);
1050                         memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
1051                         memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
1052                         break;
1053
1054                 case TRANSITION(OVS_KEY_ATTR_ICMPV6, OVS_KEY_ATTR_ND):
1055                         key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
1056                         if (swkey->ipv6.tp.src != htons(NDISC_NEIGHBOUR_SOLICITATION)
1057                             && swkey->ipv6.tp.src != htons(NDISC_NEIGHBOUR_ADVERTISEMENT))
1058                                 goto invalid;
1059                         nd_key = nla_data(nla);
1060                         memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
1061                                         sizeof(swkey->ipv6.nd.target));
1062                         memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
1063                         memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
1064                         break;
1065
1066                 default:
1067                         goto invalid;
1068                 }
1069
1070                 prev_type = type;
1071         }
1072         if (rem)
1073                 goto invalid;
1074
1075         switch (prev_type) {
1076         case OVS_KEY_ATTR_UNSPEC:
1077                 goto invalid;
1078
1079         case OVS_KEY_ATTR_PRIORITY:
1080         case OVS_KEY_ATTR_TUN_ID:
1081         case OVS_KEY_ATTR_IN_PORT:
1082                 goto invalid;
1083
1084         case OVS_KEY_ATTR_ETHERNET:
1085         case OVS_KEY_ATTR_8021Q:
1086                 goto ok;
1087
1088         case OVS_KEY_ATTR_ETHERTYPE:
1089                 if (swkey->eth.type == htons(ETH_P_IP) ||
1090                     swkey->eth.type == htons(ETH_P_IPV6) ||
1091                     swkey->eth.type == htons(ETH_P_ARP))
1092                         goto invalid;
1093                 goto ok;
1094
1095         case OVS_KEY_ATTR_IPV4:
1096                 if (swkey->ip.frag == OVS_FRAG_TYPE_LATER)
1097                         goto ok;
1098                 if (swkey->ip.proto == IPPROTO_TCP ||
1099                     swkey->ip.proto == IPPROTO_UDP ||
1100                     swkey->ip.proto == IPPROTO_ICMP)
1101                         goto invalid;
1102                 goto ok;
1103
1104         case OVS_KEY_ATTR_IPV6:
1105                 if (swkey->ip.frag == OVS_FRAG_TYPE_LATER)
1106                         goto ok;
1107                 if (swkey->ip.proto == IPPROTO_TCP ||
1108                     swkey->ip.proto == IPPROTO_UDP ||
1109                     swkey->ip.proto == IPPROTO_ICMPV6)
1110                         goto invalid;
1111                 goto ok;
1112
1113         case OVS_KEY_ATTR_ICMPV6:
1114                 if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
1115                     swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT) ||
1116                     swkey->ip.frag == OVS_FRAG_TYPE_LATER)
1117                         goto invalid;
1118                 goto ok;
1119
1120         case OVS_KEY_ATTR_TCP:
1121         case OVS_KEY_ATTR_UDP:
1122         case OVS_KEY_ATTR_ICMP:
1123         case OVS_KEY_ATTR_ND:
1124                 if (swkey->ip.frag == OVS_FRAG_TYPE_LATER)
1125                         goto invalid;
1126                 goto ok;
1127
1128         case OVS_KEY_ATTR_ARP:
1129                 goto ok;
1130
1131         default:
1132                 WARN_ON_ONCE(1);
1133         }
1134
1135 invalid:
1136         error = -EINVAL;
1137
1138 ok:
1139         *key_lenp = key_len;
1140         return error;
1141 }
1142
1143 /**
1144  * flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
1145  * @in_port: receives the extracted input port.
1146  * @tun_id: receives the extracted tunnel ID.
1147  * @key: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
1148  * sequence.
1149  *
1150  * This parses a series of Netlink attributes that form a flow key, which must
1151  * take the same form accepted by flow_from_nlattrs(), but only enough of it to
1152  * get the metadata, that is, the parts of the flow key that cannot be
1153  * extracted from the packet itself.
1154  */
1155 int flow_metadata_from_nlattrs(u32 *priority, u16 *in_port, __be64 *tun_id,
1156                                const struct nlattr *attr)
1157 {
1158         const struct nlattr *nla;
1159         u16 prev_type;
1160         int rem;
1161
1162         *in_port = USHRT_MAX;
1163         *tun_id = 0;
1164         *priority = 0;
1165
1166         prev_type = OVS_KEY_ATTR_UNSPEC;
1167         nla_for_each_nested(nla, attr, rem) {
1168                 int type = nla_type(nla);
1169
1170                 if (type > OVS_KEY_ATTR_MAX || nla_len(nla) != ovs_key_lens[type])
1171                         return -EINVAL;
1172
1173                 switch (TRANSITION(prev_type, type)) {
1174                 case TRANSITION(OVS_KEY_ATTR_UNSPEC, OVS_KEY_ATTR_PRIORITY):
1175                         *priority = nla_get_u32(nla);
1176                         break;
1177
1178                 case TRANSITION(OVS_KEY_ATTR_UNSPEC, OVS_KEY_ATTR_TUN_ID):
1179                 case TRANSITION(OVS_KEY_ATTR_PRIORITY, OVS_KEY_ATTR_TUN_ID):
1180                         *tun_id = nla_get_be64(nla);
1181                         break;
1182
1183                 case TRANSITION(OVS_KEY_ATTR_UNSPEC, OVS_KEY_ATTR_IN_PORT):
1184                 case TRANSITION(OVS_KEY_ATTR_PRIORITY, OVS_KEY_ATTR_IN_PORT):
1185                 case TRANSITION(OVS_KEY_ATTR_TUN_ID, OVS_KEY_ATTR_IN_PORT):
1186                         if (nla_get_u32(nla) >= DP_MAX_PORTS)
1187                                 return -EINVAL;
1188                         *in_port = nla_get_u32(nla);
1189                         break;
1190
1191                 default:
1192                         return 0;
1193                 }
1194
1195                 prev_type = type;
1196         }
1197         if (rem)
1198                 return -EINVAL;
1199         return 0;
1200 }
1201
1202 int flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
1203 {
1204         struct ovs_key_ethernet *eth_key;
1205         struct nlattr *nla;
1206
1207         if (swkey->phy.priority)
1208                 NLA_PUT_U32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority);
1209
1210         if (swkey->phy.tun_id != cpu_to_be64(0))
1211                 NLA_PUT_BE64(skb, OVS_KEY_ATTR_TUN_ID, swkey->phy.tun_id);
1212
1213         if (swkey->phy.in_port != USHRT_MAX)
1214                 NLA_PUT_U32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port);
1215
1216         nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
1217         if (!nla)
1218                 goto nla_put_failure;
1219         eth_key = nla_data(nla);
1220         memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
1221         memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
1222
1223         if (swkey->eth.tci != htons(0)) {
1224                 struct ovs_key_8021q q_key;
1225
1226                 q_key.q_tpid = htons(ETH_P_8021Q);
1227                 q_key.q_tci = swkey->eth.tci & ~htons(VLAN_TAG_PRESENT);
1228                 NLA_PUT(skb, OVS_KEY_ATTR_8021Q, sizeof(q_key), &q_key);
1229         }
1230
1231         if (swkey->eth.type == htons(ETH_P_802_2))
1232                 return 0;
1233
1234         NLA_PUT_BE16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type);
1235
1236         if (swkey->eth.type == htons(ETH_P_IP)) {
1237                 struct ovs_key_ipv4 *ipv4_key;
1238
1239                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
1240                 if (!nla)
1241                         goto nla_put_failure;
1242                 ipv4_key = nla_data(nla);
1243                 memset(ipv4_key, 0, sizeof(struct ovs_key_ipv4));
1244                 ipv4_key->ipv4_src = swkey->ipv4.addr.src;
1245                 ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
1246                 ipv4_key->ipv4_proto = swkey->ip.proto;
1247                 ipv4_key->ipv4_tos = swkey->ip.tos;
1248                 ipv4_key->ipv4_frag = swkey->ip.frag;
1249         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1250                 struct ovs_key_ipv6 *ipv6_key;
1251
1252                 nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
1253                 if (!nla)
1254                         goto nla_put_failure;
1255                 ipv6_key = nla_data(nla);
1256                 memset(ipv6_key, 0, sizeof(struct ovs_key_ipv6));
1257                 memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
1258                                 sizeof(ipv6_key->ipv6_src));
1259                 memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
1260                                 sizeof(ipv6_key->ipv6_dst));
1261                 ipv6_key->ipv6_label = swkey->ipv6.label;
1262                 ipv6_key->ipv6_proto = swkey->ip.proto;
1263                 ipv6_key->ipv6_tos = swkey->ip.tos;
1264                 ipv6_key->ipv6_frag = swkey->ip.frag;
1265         } else if (swkey->eth.type == htons(ETH_P_ARP)) {
1266                 struct ovs_key_arp *arp_key;
1267
1268                 nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
1269                 if (!nla)
1270                         goto nla_put_failure;
1271                 arp_key = nla_data(nla);
1272                 memset(arp_key, 0, sizeof(struct ovs_key_arp));
1273                 arp_key->arp_sip = swkey->ipv4.addr.src;
1274                 arp_key->arp_tip = swkey->ipv4.addr.dst;
1275                 arp_key->arp_op = htons(swkey->ip.proto);
1276                 memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
1277                 memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
1278         }
1279
1280         if ((swkey->eth.type == htons(ETH_P_IP) ||
1281              swkey->eth.type == htons(ETH_P_IPV6)) &&
1282              swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
1283
1284                 if (swkey->ip.proto == IPPROTO_TCP) {
1285                         struct ovs_key_tcp *tcp_key;
1286
1287                         nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
1288                         if (!nla)
1289                                 goto nla_put_failure;
1290                         tcp_key = nla_data(nla);
1291                         if (swkey->eth.type == htons(ETH_P_IP)) {
1292                                 tcp_key->tcp_src = swkey->ipv4.tp.src;
1293                                 tcp_key->tcp_dst = swkey->ipv4.tp.dst;
1294                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1295                                 tcp_key->tcp_src = swkey->ipv6.tp.src;
1296                                 tcp_key->tcp_dst = swkey->ipv6.tp.dst;
1297                         }
1298                 } else if (swkey->ip.proto == IPPROTO_UDP) {
1299                         struct ovs_key_udp *udp_key;
1300
1301                         nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
1302                         if (!nla)
1303                                 goto nla_put_failure;
1304                         udp_key = nla_data(nla);
1305                         if (swkey->eth.type == htons(ETH_P_IP)) {
1306                                 udp_key->udp_src = swkey->ipv4.tp.src;
1307                                 udp_key->udp_dst = swkey->ipv4.tp.dst;
1308                         } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
1309                                 udp_key->udp_src = swkey->ipv6.tp.src;
1310                                 udp_key->udp_dst = swkey->ipv6.tp.dst;
1311                         }
1312                 } else if (swkey->eth.type == htons(ETH_P_IP) &&
1313                            swkey->ip.proto == IPPROTO_ICMP) {
1314                         struct ovs_key_icmp *icmp_key;
1315
1316                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
1317                         if (!nla)
1318                                 goto nla_put_failure;
1319                         icmp_key = nla_data(nla);
1320                         icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
1321                         icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
1322                 } else if (swkey->eth.type == htons(ETH_P_IPV6) &&
1323                            swkey->ip.proto == IPPROTO_ICMPV6) {
1324                         struct ovs_key_icmpv6 *icmpv6_key;
1325
1326                         nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
1327                                                 sizeof(*icmpv6_key));
1328                         if (!nla)
1329                                 goto nla_put_failure;
1330                         icmpv6_key = nla_data(nla);
1331                         icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
1332                         icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
1333
1334                         if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
1335                             icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
1336                                 struct ovs_key_nd *nd_key;
1337
1338                                 nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
1339                                 if (!nla)
1340                                         goto nla_put_failure;
1341                                 nd_key = nla_data(nla);
1342                                 memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
1343                                                         sizeof(nd_key->nd_target));
1344                                 memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
1345                                 memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
1346                         }
1347                 }
1348         }
1349
1350         return 0;
1351
1352 nla_put_failure:
1353         return -EMSGSIZE;
1354 }
1355
1356 /* Initializes the flow module.
1357  * Returns zero if successful or a negative error code. */
1358 int flow_init(void)
1359 {
1360         flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
1361                                         0, NULL);
1362         if (flow_cache == NULL)
1363                 return -ENOMEM;
1364
1365         get_random_bytes(&hash_seed, sizeof(hash_seed));
1366
1367         return 0;
1368 }
1369
1370 /* Uninitializes the flow module. */
1371 void flow_exit(void)
1372 {
1373         kmem_cache_destroy(flow_cache);
1374 }