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 <asm/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/tcp.h>
  28 #include <linux/udp.h>
  29 #include <linux/icmp.h>
  30 #include <net/inet_ecn.h>
  31 #include <net/ip.h>
  32
  33 static struct kmem_cache *flow_cache;
  34 static unsigned int hash_seed __read_mostly;
  35
  36 static inline bool arphdr_ok(struct sk_buff *skb)
  37 {
  38         return skb->len >= skb_network_offset(skb) + sizeof(struct arp_eth_header);
  39 }
  40
  41 static inline int check_iphdr(struct sk_buff *skb)
  42 {
  43         unsigned int nh_ofs = skb_network_offset(skb);
  44         unsigned int ip_len;
  45
  46         if (skb->len < nh_ofs + sizeof(struct iphdr))
  47                 return -EINVAL;
  48
  49         ip_len = ip_hdrlen(skb);
  50         if (ip_len < sizeof(struct iphdr) || skb->len < nh_ofs + ip_len)
  51                 return -EINVAL;
  52
  53         /*
  54          * Pull enough header bytes to account for the IP header plus the
  55          * longest transport header that we parse, currently 20 bytes for TCP.
  56          */
  57         if (!pskb_may_pull(skb, min(nh_ofs + ip_len + 20, skb->len)))
  58                 return -ENOMEM;
  59
  60         skb_set_transport_header(skb, nh_ofs + ip_len);
  61         return 0;
  62 }
  63
  64 static inline bool tcphdr_ok(struct sk_buff *skb)
  65 {
  66         int th_ofs = skb_transport_offset(skb);
  67         if (skb->len >= th_ofs + sizeof(struct tcphdr)) {
  68                 int tcp_len = tcp_hdrlen(skb);
  69                 return (tcp_len >= sizeof(struct tcphdr)
  70                         && skb->len >= th_ofs + tcp_len);
  71         }
  72         return false;
  73 }
  74
  75 static inline bool udphdr_ok(struct sk_buff *skb)
  76 {
  77         return skb->len >= skb_transport_offset(skb) + sizeof(struct udphdr);
  78 }
  79
  80 static inline bool icmphdr_ok(struct sk_buff *skb)
  81 {
  82         return skb->len >= skb_transport_offset(skb) + sizeof(struct icmphdr);
  83 }
  84
  85 u64 flow_used_time(unsigned long flow_jiffies)
  86 {
  87         struct timespec cur_ts;
  88         u64 cur_ms, idle_ms;
  89
  90         ktime_get_ts(&cur_ts);
  91         idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
  92         cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
  93                  cur_ts.tv_nsec / NSEC_PER_MSEC;
  94
  95         return cur_ms - idle_ms;
  96 }
  97
  98
  99 #define TCP_FLAGS_OFFSET 13
 100 #define TCP_FLAG_MASK 0x3f
 101
 102 void flow_used(struct sw_flow *flow, struct sk_buff *skb)
 103 {
 104         u8 tcp_flags = 0;
 105
 106         if (flow->key.dl_type == htons(ETH_P_IP) &&
 107             flow->key.nw_proto == IPPROTO_TCP) {
 108                 u8 *tcp = (u8 *)tcp_hdr(skb);
 109                 tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
 110         }
 111
 112         spin_lock_bh(&flow->lock);
 113         flow->used = jiffies;
 114         flow->packet_count++;
 115         flow->byte_count += skb->len;
 116         flow->tcp_flags |= tcp_flags;
 117         spin_unlock_bh(&flow->lock);
 118 }
 119
 120 struct sw_flow_actions *flow_actions_alloc(const struct nlattr *actions)
 121 {
 122         int actions_len = nla_len(actions);
 123         struct sw_flow_actions *sfa;
 124
 125         /* At least DP_MAX_PORTS actions are required to be able to flood a
 126          * packet to every port.  Factor of 2 allows for setting VLAN tags,
 127          * etc. */
 128         if (actions_len > 2 * DP_MAX_PORTS * nla_total_size(4))
 129                 return ERR_PTR(-EINVAL);
 130
 131         sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
 132         if (!sfa)
 133                 return ERR_PTR(-ENOMEM);
 134
 135         sfa->actions_len = actions_len;
 136         memcpy(sfa->actions, nla_data(actions), actions_len);
 137         return sfa;
 138 }
 139
 140 struct sw_flow *flow_alloc(void)
 141 {
 142         struct sw_flow *flow;
 143
 144         flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
 145         if (!flow)
 146                 return ERR_PTR(-ENOMEM);
 147
 148         spin_lock_init(&flow->lock);
 149         atomic_set(&flow->refcnt, 1);
 150         flow->dead = false;
 151
 152         return flow;
 153 }
 154
 155 void flow_free_tbl(struct tbl_node *node)
 156 {
 157         struct sw_flow *flow = flow_cast(node);
 158
 159         flow->dead = true;
 160         flow_put(flow);
 161 }
 162
 163 /* RCU callback used by flow_deferred_free. */
 164 static void rcu_free_flow_callback(struct rcu_head *rcu)
 165 {
 166         struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
 167
 168         flow->dead = true;
 169         flow_put(flow);
 170 }
 171
 172 /* Schedules 'flow' to be freed after the next RCU grace period.
 173  * The caller must hold rcu_read_lock for this to be sensible. */
 174 void flow_deferred_free(struct sw_flow *flow)
 175 {
 176         call_rcu(&flow->rcu, rcu_free_flow_callback);
 177 }
 178
 179 void flow_hold(struct sw_flow *flow)
 180 {
 181         atomic_inc(&flow->refcnt);
 182 }
 183
 184 void flow_put(struct sw_flow *flow)
 185 {
 186         if (unlikely(!flow))
 187                 return;
 188
 189         if (atomic_dec_and_test(&flow->refcnt)) {
 190                 kfree((struct sf_flow_acts __force *)flow->sf_acts);
 191                 kmem_cache_free(flow_cache, flow);
 192         }
 193 }
 194
 195 /* RCU callback used by flow_deferred_free_acts. */
 196 static void rcu_free_acts_callback(struct rcu_head *rcu)
 197 {
 198         struct sw_flow_actions *sf_acts = container_of(rcu,
 199                         struct sw_flow_actions, rcu);
 200         kfree(sf_acts);
 201 }
 202
 203 /* Schedules 'sf_acts' to be freed after the next RCU grace period.
 204  * The caller must hold rcu_read_lock for this to be sensible. */
 205 void flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
 206 {
 207         call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
 208 }
 209
 210 static void parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
 211 {
 212         struct qtag_prefix {
 213                 __be16 eth_type; /* ETH_P_8021Q */
 214                 __be16 tci;
 215         };
 216         struct qtag_prefix *qp;
 217
 218         if (skb->len < sizeof(struct qtag_prefix) + sizeof(__be16))
 219                 return;
 220
 221         qp = (struct qtag_prefix *) skb->data;
 222         key->dl_tci = qp->tci | htons(VLAN_TAG_PRESENT);
 223         __skb_pull(skb, sizeof(struct qtag_prefix));
 224 }
 225
 226 static __be16 parse_ethertype(struct sk_buff *skb)
 227 {
 228         struct llc_snap_hdr {
 229                 u8  dsap;  /* Always 0xAA */
 230                 u8  ssap;  /* Always 0xAA */
 231                 u8  ctrl;
 232                 u8  oui[3];
 233                 __be16 ethertype;
 234         };
 235         struct llc_snap_hdr *llc;
 236         __be16 proto;
 237
 238         proto = *(__be16 *) skb->data;
 239         __skb_pull(skb, sizeof(__be16));
 240
 241         if (ntohs(proto) >= 1536)
 242                 return proto;
 243
 244         if (unlikely(skb->len < sizeof(struct llc_snap_hdr)))
 245                 return htons(ETH_P_802_2);
 246
 247         llc = (struct llc_snap_hdr *) skb->data;
 248         if (llc->dsap != LLC_SAP_SNAP ||
 249             llc->ssap != LLC_SAP_SNAP ||
 250             (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
 251                 return htons(ETH_P_802_2);
 252
 253         __skb_pull(skb, sizeof(struct llc_snap_hdr));
 254         return llc->ethertype;
 255 }
 256
 257 /**
 258  * flow_extract - extracts a flow key from an Ethernet frame.
 259  * @skb: sk_buff that contains the frame, with skb->data pointing to the
 260  * Ethernet header
 261  * @in_port: port number on which @skb was received.
 262  * @key: output flow key
 263  * @is_frag: set to 1 if @skb contains an IPv4 fragment, or to 0 if @skb does
 264  * not contain an IPv4 packet or if it is not a fragment.
 265  *
 266  * The caller must ensure that skb->len >= ETH_HLEN.
 267  *
 268  * Returns 0 if successful, otherwise a negative errno value.
 269  *
 270  * Initializes @skb header pointers as follows:
 271  *
 272  *    - skb->mac_header: the Ethernet header.
 273  *
 274  *    - skb->network_header: just past the Ethernet header, or just past the
 275  *      VLAN header, to the first byte of the Ethernet payload.
 276  *
 277  *    - skb->transport_header: If key->dl_type is ETH_P_IP on output, then just
 278  *      past the IPv4 header, if one is present and of a correct length,
 279  *      otherwise the same as skb->network_header.  For other key->dl_type
 280  *      values it is left untouched.
 281  */
 282 int flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
 283                  bool *is_frag)
 284 {
 285         struct ethhdr *eth;
 286
 287         memset(key, 0, sizeof(*key));
 288         key->tun_id = OVS_CB(skb)->tun_id;
 289         key->in_port = in_port;
 290         *is_frag = false;
 291
 292         /*
 293          * We would really like to pull as many bytes as we could possibly
 294          * want to parse into the linear data area.  Currently that is:
 295          *
 296          *    14     Ethernet header
 297          *     4     VLAN header
 298          *    60     max IP header with options
 299          *    20     max TCP/UDP/ICMP header (don't care about options)
 300          *    --
 301          *    98
 302          *
 303          * But Xen only allocates 64 or 72 bytes for the linear data area in
 304          * netback, which means that we would reallocate and copy the skb's
 305          * linear data on every packet if we did that.  So instead just pull 64
 306          * bytes, which is always sufficient without IP options, and then check
 307          * whether we need to pull more later when we look at the IP header.
 308          */
 309         if (!pskb_may_pull(skb, min(skb->len, 64u)))
 310                 return -ENOMEM;
 311
 312         skb_reset_mac_header(skb);
 313
 314         /* Link layer. */
 315         eth = eth_hdr(skb);
 316         memcpy(key->dl_src, eth->h_source, ETH_ALEN);
 317         memcpy(key->dl_dst, eth->h_dest, ETH_ALEN);
 318
 319         /* dl_type, dl_vlan, dl_vlan_pcp. */
 320         __skb_pull(skb, 2 * ETH_ALEN);
 321         if (eth->h_proto == htons(ETH_P_8021Q))
 322                 parse_vlan(skb, key);
 323         key->dl_type = parse_ethertype(skb);
 324         skb_reset_network_header(skb);
 325         __skb_push(skb, skb->data - (unsigned char *)eth);
 326
 327         /* Network layer. */
 328         if (key->dl_type == htons(ETH_P_IP)) {
 329                 struct iphdr *nh;
 330                 int error;
 331
 332                 error = check_iphdr(skb);
 333                 if (unlikely(error)) {
 334                         if (error == -EINVAL) {
 335                                 skb->transport_header = skb->network_header;
 336                                 return 0;
 337                         }
 338                         return error;
 339                 }
 340
 341                 nh = ip_hdr(skb);
 342                 key->nw_src = nh->saddr;
 343                 key->nw_dst = nh->daddr;
 344                 key->nw_tos = nh->tos & ~INET_ECN_MASK;
 345                 key->nw_proto = nh->protocol;
 346
 347                 /* Transport layer. */
 348                 if (!(nh->frag_off & htons(IP_MF | IP_OFFSET)) &&
 349                     !(skb_shinfo(skb)->gso_type & SKB_GSO_UDP)) {
 350                         if (key->nw_proto == IPPROTO_TCP) {
 351                                 if (tcphdr_ok(skb)) {
 352                                         struct tcphdr *tcp = tcp_hdr(skb);
 353                                         key->tp_src = tcp->source;
 354                                         key->tp_dst = tcp->dest;
 355                                 }
 356                         } else if (key->nw_proto == IPPROTO_UDP) {
 357                                 if (udphdr_ok(skb)) {
 358                                         struct udphdr *udp = udp_hdr(skb);
 359                                         key->tp_src = udp->source;
 360                                         key->tp_dst = udp->dest;
 361                                 }
 362                         } else if (key->nw_proto == IPPROTO_ICMP) {
 363                                 if (icmphdr_ok(skb)) {
 364                                         struct icmphdr *icmp = icmp_hdr(skb);
 365                                         /* The ICMP type and code fields use the 16-bit
 366                                          * transport port fields, so we need to store them
 367                                          * in 16-bit network byte order. */
 368                                         key->tp_src = htons(icmp->type);
 369                                         key->tp_dst = htons(icmp->code);
 370                                 }
 371                         }
 372                 } else
 373                         *is_frag = true;
 374
 375         } else if (key->dl_type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
 376                 struct arp_eth_header *arp;
 377
 378                 arp = (struct arp_eth_header *)skb_network_header(skb);
 379
 380                 if (arp->ar_hrd == htons(ARPHRD_ETHER)
 381                                 && arp->ar_pro == htons(ETH_P_IP)
 382                                 && arp->ar_hln == ETH_ALEN
 383                                 && arp->ar_pln == 4) {
 384
 385                         /* We only match on the lower 8 bits of the opcode. */
 386                         if (ntohs(arp->ar_op) <= 0xff)
 387                                 key->nw_proto = ntohs(arp->ar_op);
 388
 389                         if (key->nw_proto == ARPOP_REQUEST
 390                                         || key->nw_proto == ARPOP_REPLY) {
 391                                 memcpy(&key->nw_src, arp->ar_sip, sizeof(key->nw_src));
 392                                 memcpy(&key->nw_dst, arp->ar_tip, sizeof(key->nw_dst));
 393                         }
 394                 }
 395         }
 396         return 0;
 397 }
 398
 399 u32 flow_hash(const struct sw_flow_key *key)
 400 {
 401         return jhash2((u32*)key, sizeof(*key) / sizeof(u32), hash_seed);
 402 }
 403
 404 int flow_cmp(const struct tbl_node *node, void *key2_)
 405 {
 406         const struct sw_flow_key *key1 = &flow_cast(node)->key;
 407         const struct sw_flow_key *key2 = key2_;
 408
 409         return !memcmp(key1, key2, sizeof(struct sw_flow_key));
 410 }
 411
 412 /**
 413  * flow_from_nlattrs - parses Netlink attributes into a flow key.
 414  * @swkey: receives the extracted flow key.
 415  * @key: Netlink attribute holding nested %ODP_KEY_ATTR_* Netlink attribute
 416  * sequence.
 417  *
 418  * This state machine accepts the following forms, with [] for optional
 419  * elements and | for alternatives:
 420  *
 421  * [tun_id] in_port ethernet [8021q] [ethertype [IP [TCP|UDP|ICMP] | ARP]
 422  */
 423 int flow_from_nlattrs(struct sw_flow_key *swkey, const struct nlattr *attr)
 424 {
 425         const struct nlattr *nla;
 426         u16 prev_type;
 427         int rem;
 428
 429         memset(swkey, 0, sizeof(*swkey));
 430         swkey->dl_type = htons(ETH_P_802_2);
 431
 432         prev_type = ODP_KEY_ATTR_UNSPEC;
 433         nla_for_each_nested(nla, attr, rem) {
 434                 static const u32 key_lens[ODP_KEY_ATTR_MAX + 1] = {
 435                         [ODP_KEY_ATTR_TUN_ID] = 8,
 436                         [ODP_KEY_ATTR_IN_PORT] = 4,
 437                         [ODP_KEY_ATTR_ETHERNET] = sizeof(struct odp_key_ethernet),
 438                         [ODP_KEY_ATTR_8021Q] = sizeof(struct odp_key_8021q),
 439                         [ODP_KEY_ATTR_ETHERTYPE] = 2,
 440                         [ODP_KEY_ATTR_IPV4] = sizeof(struct odp_key_ipv4),
 441                         [ODP_KEY_ATTR_TCP] = sizeof(struct odp_key_tcp),
 442                         [ODP_KEY_ATTR_UDP] = sizeof(struct odp_key_udp),
 443                         [ODP_KEY_ATTR_ICMP] = sizeof(struct odp_key_icmp),
 444                         [ODP_KEY_ATTR_ARP] = sizeof(struct odp_key_arp),
 445                 };
 446
 447                 const struct odp_key_ethernet *eth_key;
 448                 const struct odp_key_8021q *q_key;
 449                 const struct odp_key_ipv4 *ipv4_key;
 450                 const struct odp_key_tcp *tcp_key;
 451                 const struct odp_key_udp *udp_key;
 452                 const struct odp_key_icmp *icmp_key;
 453                 const struct odp_key_arp *arp_key;
 454
 455                 int type = nla_type(nla);
 456
 457                 if (type > ODP_KEY_ATTR_MAX || nla_len(nla) != key_lens[type])
 458                         return -EINVAL;
 459
 460 #define TRANSITION(PREV_TYPE, TYPE) (((PREV_TYPE) << 16) | (TYPE))
 461                 switch (TRANSITION(prev_type, type)) {
 462                 case TRANSITION(ODP_KEY_ATTR_UNSPEC, ODP_KEY_ATTR_TUN_ID):
 463                         swkey->tun_id = nla_get_be64(nla);
 464                         break;
 465
 466                 case TRANSITION(ODP_KEY_ATTR_UNSPEC, ODP_KEY_ATTR_IN_PORT):
 467                 case TRANSITION(ODP_KEY_ATTR_TUN_ID, ODP_KEY_ATTR_IN_PORT):
 468                         if (nla_get_u32(nla) >= DP_MAX_PORTS)
 469                                 return -EINVAL;
 470                         swkey->in_port = nla_get_u32(nla);
 471                         break;
 472
 473                 case TRANSITION(ODP_KEY_ATTR_IN_PORT, ODP_KEY_ATTR_ETHERNET):
 474                         eth_key = nla_data(nla);
 475                         memcpy(swkey->dl_src, eth_key->eth_src, ETH_ALEN);
 476                         memcpy(swkey->dl_dst, eth_key->eth_dst, ETH_ALEN);
 477                         break;
 478
 479                 case TRANSITION(ODP_KEY_ATTR_ETHERNET, ODP_KEY_ATTR_8021Q):
 480                         q_key = nla_data(nla);
 481                         /* Only standard 0x8100 VLANs currently supported. */
 482                         if (q_key->q_tpid != htons(ETH_P_8021Q))
 483                                 return -EINVAL;
 484                         if (q_key->q_tci & htons(VLAN_TAG_PRESENT))
 485                                 return -EINVAL;
 486                         swkey->dl_tci = q_key->q_tci | htons(VLAN_TAG_PRESENT);
 487                         break;
 488
 489                 case TRANSITION(ODP_KEY_ATTR_8021Q, ODP_KEY_ATTR_ETHERTYPE):
 490                 case TRANSITION(ODP_KEY_ATTR_ETHERNET, ODP_KEY_ATTR_ETHERTYPE):
 491                         swkey->dl_type = nla_get_be16(nla);
 492                         if (ntohs(swkey->dl_type) < 1536)
 493                                 return -EINVAL;
 494                         break;
 495
 496                 case TRANSITION(ODP_KEY_ATTR_ETHERTYPE, ODP_KEY_ATTR_IPV4):
 497                         if (swkey->dl_type != htons(ETH_P_IP))
 498                                 return -EINVAL;
 499                         ipv4_key = nla_data(nla);
 500                         swkey->nw_src = ipv4_key->ipv4_src;
 501                         swkey->nw_dst = ipv4_key->ipv4_dst;
 502                         swkey->nw_proto = ipv4_key->ipv4_proto;
 503                         swkey->nw_tos = ipv4_key->ipv4_tos;
 504                         if (swkey->nw_tos & INET_ECN_MASK)
 505                                 return -EINVAL;
 506                         break;
 507
 508                 case TRANSITION(ODP_KEY_ATTR_IPV4, ODP_KEY_ATTR_TCP):
 509                         if (swkey->nw_proto != IPPROTO_TCP)
 510                                 return -EINVAL;
 511                         tcp_key = nla_data(nla);
 512                         swkey->tp_src = tcp_key->tcp_src;
 513                         swkey->tp_dst = tcp_key->tcp_dst;
 514                         break;
 515
 516                 case TRANSITION(ODP_KEY_ATTR_IPV4, ODP_KEY_ATTR_UDP):
 517                         if (swkey->nw_proto != IPPROTO_UDP)
 518                                 return -EINVAL;
 519                         udp_key = nla_data(nla);
 520                         swkey->tp_src = udp_key->udp_src;
 521                         swkey->tp_dst = udp_key->udp_dst;
 522                         break;
 523
 524                 case TRANSITION(ODP_KEY_ATTR_IPV4, ODP_KEY_ATTR_ICMP):
 525                         if (swkey->nw_proto != IPPROTO_ICMP)
 526                                 return -EINVAL;
 527                         icmp_key = nla_data(nla);
 528                         swkey->tp_src = htons(icmp_key->icmp_type);
 529                         swkey->tp_dst = htons(icmp_key->icmp_code);
 530                         break;
 531
 532                 case TRANSITION(ODP_KEY_ATTR_ETHERTYPE, ODP_KEY_ATTR_ARP):
 533                         if (swkey->dl_type != htons(ETH_P_ARP))
 534                                 return -EINVAL;
 535                         arp_key = nla_data(nla);
 536                         swkey->nw_src = arp_key->arp_sip;
 537                         swkey->nw_dst = arp_key->arp_tip;
 538                         if (arp_key->arp_op & htons(0xff00))
 539                                 return -EINVAL;
 540                         swkey->nw_proto = ntohs(arp_key->arp_op);
 541                         break;
 542
 543                 default:
 544                         return -EINVAL;
 545                 }
 546
 547                 prev_type = type;
 548         }
 549         if (rem)
 550                 return -EINVAL;
 551
 552         switch (prev_type) {
 553         case ODP_KEY_ATTR_UNSPEC:
 554                 return -EINVAL;
 555
 556         case ODP_KEY_ATTR_TUN_ID:
 557         case ODP_KEY_ATTR_IN_PORT:
 558                 return -EINVAL;
 559
 560         case ODP_KEY_ATTR_ETHERNET:
 561         case ODP_KEY_ATTR_8021Q:
 562                 return 0;
 563
 564         case ODP_KEY_ATTR_ETHERTYPE:
 565                 if (swkey->dl_type == htons(ETH_P_IP) ||
 566                     swkey->dl_type == htons(ETH_P_ARP))
 567                         return -EINVAL;
 568                 return 0;
 569
 570         case ODP_KEY_ATTR_IPV4:
 571                 if (swkey->nw_proto == IPPROTO_TCP ||
 572                     swkey->nw_proto == IPPROTO_UDP ||
 573                     swkey->nw_proto == IPPROTO_ICMP)
 574                         return -EINVAL;
 575                 return 0;
 576
 577         case ODP_KEY_ATTR_TCP:
 578         case ODP_KEY_ATTR_UDP:
 579         case ODP_KEY_ATTR_ICMP:
 580         case ODP_KEY_ATTR_ARP:
 581                 return 0;
 582         }
 583
 584         WARN_ON_ONCE(1);
 585         return -EINVAL;
 586 }
 587
 588 int flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
 589 {
 590         struct odp_key_ethernet *eth_key;
 591         struct nlattr *nla;
 592
 593         if (swkey->tun_id != cpu_to_be64(0))
 594                 NLA_PUT_BE64(skb, ODP_KEY_ATTR_TUN_ID, swkey->tun_id);
 595
 596         NLA_PUT_U32(skb, ODP_KEY_ATTR_IN_PORT, swkey->in_port);
 597
 598         nla = nla_reserve(skb, ODP_KEY_ATTR_ETHERNET, sizeof(*eth_key));
 599         if (!nla)
 600                 goto nla_put_failure;
 601         eth_key = nla_data(nla);
 602         memcpy(eth_key->eth_src, swkey->dl_src, ETH_ALEN);
 603         memcpy(eth_key->eth_dst, swkey->dl_dst, ETH_ALEN);
 604
 605         if (swkey->dl_tci != htons(0)) {
 606                 struct odp_key_8021q q_key;
 607
 608                 q_key.q_tpid = htons(ETH_P_8021Q);
 609                 q_key.q_tci = swkey->dl_tci & ~htons(VLAN_TAG_PRESENT);
 610                 NLA_PUT(skb, ODP_KEY_ATTR_8021Q, sizeof(q_key), &q_key);
 611         }
 612
 613         if (swkey->dl_type == htons(ETH_P_802_2))
 614                 return 0;
 615
 616         NLA_PUT_BE16(skb, ODP_KEY_ATTR_ETHERTYPE, swkey->dl_type);
 617
 618         if (swkey->dl_type == htons(ETH_P_IP)) {
 619                 struct odp_key_ipv4 *ipv4_key;
 620
 621                 nla = nla_reserve(skb, ODP_KEY_ATTR_IPV4, sizeof(*ipv4_key));
 622                 if (!nla)
 623                         goto nla_put_failure;
 624                 ipv4_key = nla_data(nla);
 625                 ipv4_key->ipv4_src = swkey->nw_src;
 626                 ipv4_key->ipv4_dst = swkey->nw_dst;
 627                 ipv4_key->ipv4_proto = swkey->nw_proto;
 628                 ipv4_key->ipv4_tos = swkey->nw_tos;
 629
 630                 if (swkey->nw_proto == IPPROTO_TCP) {
 631                         struct odp_key_tcp *tcp_key;
 632
 633                         nla = nla_reserve(skb, ODP_KEY_ATTR_TCP, sizeof(*tcp_key));
 634                         if (!nla)
 635                                 goto nla_put_failure;
 636                         tcp_key = nla_data(nla);
 637                         tcp_key->tcp_src = swkey->tp_src;
 638                         tcp_key->tcp_dst = swkey->tp_dst;
 639                 } else if (swkey->nw_proto == IPPROTO_UDP) {
 640                         struct odp_key_udp *udp_key;
 641
 642                         nla = nla_reserve(skb, ODP_KEY_ATTR_UDP, sizeof(*udp_key));
 643                         if (!nla)
 644                                 goto nla_put_failure;
 645                         udp_key = nla_data(nla);
 646                         udp_key->udp_src = swkey->tp_src;
 647                         udp_key->udp_dst = swkey->tp_dst;
 648                 } else if (swkey->nw_proto == IPPROTO_ICMP) {
 649                         struct odp_key_icmp *icmp_key;
 650
 651                         nla = nla_reserve(skb, ODP_KEY_ATTR_ICMP, sizeof(*icmp_key));
 652                         if (!nla)
 653                                 goto nla_put_failure;
 654                         icmp_key = nla_data(nla);
 655                         icmp_key->icmp_type = ntohs(swkey->tp_src);
 656                         icmp_key->icmp_code = ntohs(swkey->tp_dst);
 657                 }
 658         } else if (swkey->dl_type == htons(ETH_P_ARP)) {
 659                 struct odp_key_arp *arp_key;
 660
 661                 nla = nla_reserve(skb, ODP_KEY_ATTR_ARP, sizeof(*arp_key));
 662                 if (!nla)
 663                         goto nla_put_failure;
 664                 arp_key = nla_data(nla);
 665                 arp_key->arp_sip = swkey->nw_src;
 666                 arp_key->arp_tip = swkey->nw_dst;
 667                 arp_key->arp_op = htons(swkey->nw_proto);
 668         }
 669
 670         return 0;
 671
 672 nla_put_failure:
 673         return -EMSGSIZE;
 674 }
 675
 676 /* Initializes the flow module.
 677  * Returns zero if successful or a negative error code. */
 678 int flow_init(void)
 679 {
 680         flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
 681                                         0, NULL);
 682         if (flow_cache == NULL)
 683                 return -ENOMEM;
 684
 685         get_random_bytes(&hash_seed, sizeof(hash_seed));
 686
 687         return 0;
 688 }
 689
 690 /* Uninitializes the flow module. */
 691 void flow_exit(void)
 692 {
 693         kmem_cache_destroy(flow_cache);
 694 }