drivers/net/ipvlan/ipvlan_core.c

   1 /* Copyright (c) 2014 Mahesh Bandewar <maheshb@google.com>
   2  *
   3  * This program is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU General Public License as
   5  * published by the Free Software Foundation; either version 2 of
   6  * the License, or (at your option) any later version.
   7  *
   8  */
   9
  10 #include "ipvlan.h"
  11
  12 static u32 ipvlan_jhash_secret __read_mostly;
  13
  14 void ipvlan_init_secret(void)
  15 {
  16         net_get_random_once(&ipvlan_jhash_secret, sizeof(ipvlan_jhash_secret));
  17 }
  18
  19 static void ipvlan_count_rx(const struct ipvl_dev *ipvlan,
  20                             unsigned int len, bool success, bool mcast)
  21 {
  22         if (!ipvlan)
  23                 return;
  24
  25         if (likely(success)) {
  26                 struct ipvl_pcpu_stats *pcptr;
  27
  28                 pcptr = this_cpu_ptr(ipvlan->pcpu_stats);
  29                 u64_stats_update_begin(&pcptr->syncp);
  30                 pcptr->rx_pkts++;
  31                 pcptr->rx_bytes += len;
  32                 if (mcast)
  33                         pcptr->rx_mcast++;
  34                 u64_stats_update_end(&pcptr->syncp);
  35         } else {
  36                 this_cpu_inc(ipvlan->pcpu_stats->rx_errs);
  37         }
  38 }
  39
  40 static u8 ipvlan_get_v6_hash(const void *iaddr)
  41 {
  42         const struct in6_addr *ip6_addr = iaddr;
  43
  44         return __ipv6_addr_jhash(ip6_addr, ipvlan_jhash_secret) &
  45                IPVLAN_HASH_MASK;
  46 }
  47
  48 static u8 ipvlan_get_v4_hash(const void *iaddr)
  49 {
  50         const struct in_addr *ip4_addr = iaddr;
  51
  52         return jhash_1word(ip4_addr->s_addr, ipvlan_jhash_secret) &
  53                IPVLAN_HASH_MASK;
  54 }
  55
  56 static struct ipvl_addr *ipvlan_ht_addr_lookup(const struct ipvl_port *port,
  57                                                const void *iaddr, bool is_v6)
  58 {
  59         struct ipvl_addr *addr;
  60         u8 hash;
  61
  62         hash = is_v6 ? ipvlan_get_v6_hash(iaddr) :
  63                ipvlan_get_v4_hash(iaddr);
  64         hlist_for_each_entry_rcu(addr, &port->hlhead[hash], hlnode) {
  65                 if (is_v6 && addr->atype == IPVL_IPV6 &&
  66                     ipv6_addr_equal(&addr->ip6addr, iaddr))
  67                         return addr;
  68                 else if (!is_v6 && addr->atype == IPVL_IPV4 &&
  69                          addr->ip4addr.s_addr ==
  70                                 ((struct in_addr *)iaddr)->s_addr)
  71                         return addr;
  72         }
  73         return NULL;
  74 }
  75
  76 void ipvlan_ht_addr_add(struct ipvl_dev *ipvlan, struct ipvl_addr *addr)
  77 {
  78         struct ipvl_port *port = ipvlan->port;
  79         u8 hash;
  80
  81         hash = (addr->atype == IPVL_IPV6) ?
  82                ipvlan_get_v6_hash(&addr->ip6addr) :
  83                ipvlan_get_v4_hash(&addr->ip4addr);
  84         if (hlist_unhashed(&addr->hlnode))
  85                 hlist_add_head_rcu(&addr->hlnode, &port->hlhead[hash]);
  86 }
  87
  88 void ipvlan_ht_addr_del(struct ipvl_addr *addr)
  89 {
  90         hlist_del_init_rcu(&addr->hlnode);
  91 }
  92
  93 struct ipvl_addr *ipvlan_find_addr(const struct ipvl_dev *ipvlan,
  94                                    const void *iaddr, bool is_v6)
  95 {
  96         struct ipvl_addr *addr;
  97
  98         list_for_each_entry(addr, &ipvlan->addrs, anode) {
  99                 if ((is_v6 && addr->atype == IPVL_IPV6 &&
 100                     ipv6_addr_equal(&addr->ip6addr, iaddr)) ||
 101                     (!is_v6 && addr->atype == IPVL_IPV4 &&
 102                     addr->ip4addr.s_addr == ((struct in_addr *)iaddr)->s_addr))
 103                         return addr;
 104         }
 105         return NULL;
 106 }
 107
 108 bool ipvlan_addr_busy(struct ipvl_port *port, void *iaddr, bool is_v6)
 109 {
 110         struct ipvl_dev *ipvlan;
 111
 112         ASSERT_RTNL();
 113
 114         list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
 115                 if (ipvlan_find_addr(ipvlan, iaddr, is_v6))
 116                         return true;
 117         }
 118         return false;
 119 }
 120
 121 static void *ipvlan_get_L3_hdr(struct sk_buff *skb, int *type)
 122 {
 123         void *lyr3h = NULL;
 124
 125         switch (skb->protocol) {
 126         case htons(ETH_P_ARP): {
 127                 struct arphdr *arph;
 128
 129                 if (unlikely(!pskb_may_pull(skb, sizeof(*arph))))
 130                         return NULL;
 131
 132                 arph = arp_hdr(skb);
 133                 *type = IPVL_ARP;
 134                 lyr3h = arph;
 135                 break;
 136         }
 137         case htons(ETH_P_IP): {
 138                 u32 pktlen;
 139                 struct iphdr *ip4h;
 140
 141                 if (unlikely(!pskb_may_pull(skb, sizeof(*ip4h))))
 142                         return NULL;
 143
 144                 ip4h = ip_hdr(skb);
 145                 pktlen = ntohs(ip4h->tot_len);
 146                 if (ip4h->ihl < 5 || ip4h->version != 4)
 147                         return NULL;
 148                 if (skb->len < pktlen || pktlen < (ip4h->ihl * 4))
 149                         return NULL;
 150
 151                 *type = IPVL_IPV4;
 152                 lyr3h = ip4h;
 153                 break;
 154         }
 155         case htons(ETH_P_IPV6): {
 156                 struct ipv6hdr *ip6h;
 157
 158                 if (unlikely(!pskb_may_pull(skb, sizeof(*ip6h))))
 159                         return NULL;
 160
 161                 ip6h = ipv6_hdr(skb);
 162                 if (ip6h->version != 6)
 163                         return NULL;
 164
 165                 *type = IPVL_IPV6;
 166                 lyr3h = ip6h;
 167                 /* Only Neighbour Solicitation pkts need different treatment */
 168                 if (ipv6_addr_any(&ip6h->saddr) &&
 169                     ip6h->nexthdr == NEXTHDR_ICMP) {
 170                         *type = IPVL_ICMPV6;
 171                         lyr3h = ip6h + 1;
 172                 }
 173                 break;
 174         }
 175         default:
 176                 return NULL;
 177         }
 178
 179         return lyr3h;
 180 }
 181
 182 unsigned int ipvlan_mac_hash(const unsigned char *addr)
 183 {
 184         u32 hash = jhash_1word(__get_unaligned_cpu32(addr+2),
 185                                ipvlan_jhash_secret);
 186
 187         return hash & IPVLAN_MAC_FILTER_MASK;
 188 }
 189
 190 void ipvlan_process_multicast(struct work_struct *work)
 191 {
 192         struct ipvl_port *port = container_of(work, struct ipvl_port, wq);
 193         struct ethhdr *ethh;
 194         struct ipvl_dev *ipvlan;
 195         struct sk_buff *skb, *nskb;
 196         struct sk_buff_head list;
 197         unsigned int len;
 198         unsigned int mac_hash;
 199         int ret;
 200         u8 pkt_type;
 201         bool tx_pkt;
 202
 203         __skb_queue_head_init(&list);
 204
 205         spin_lock_bh(&port->backlog.lock);
 206         skb_queue_splice_tail_init(&port->backlog, &list);
 207         spin_unlock_bh(&port->backlog.lock);
 208
 209         while ((skb = __skb_dequeue(&list)) != NULL) {
 210                 struct net_device *dev = skb->dev;
 211                 bool consumed = false;
 212
 213                 ethh = eth_hdr(skb);
 214                 tx_pkt = IPVL_SKB_CB(skb)->tx_pkt;
 215                 mac_hash = ipvlan_mac_hash(ethh->h_dest);
 216
 217                 if (ether_addr_equal(ethh->h_dest, port->dev->broadcast))
 218                         pkt_type = PACKET_BROADCAST;
 219                 else
 220                         pkt_type = PACKET_MULTICAST;
 221
 222                 rcu_read_lock();
 223                 list_for_each_entry_rcu(ipvlan, &port->ipvlans, pnode) {
 224                         if (tx_pkt && (ipvlan->dev == skb->dev))
 225                                 continue;
 226                         if (!test_bit(mac_hash, ipvlan->mac_filters))
 227                                 continue;
 228                         if (!(ipvlan->dev->flags & IFF_UP))
 229                                 continue;
 230                         ret = NET_RX_DROP;
 231                         len = skb->len + ETH_HLEN;
 232                         nskb = skb_clone(skb, GFP_ATOMIC);
 233                         local_bh_disable();
 234                         if (nskb) {
 235                                 consumed = true;
 236                                 nskb->pkt_type = pkt_type;
 237                                 nskb->dev = ipvlan->dev;
 238                                 if (tx_pkt)
 239                                         ret = dev_forward_skb(ipvlan->dev, nskb);
 240                                 else
 241                                         ret = netif_rx(nskb);
 242                         }
 243                         ipvlan_count_rx(ipvlan, len, ret == NET_RX_SUCCESS, true);
 244                         local_bh_enable();
 245                 }
 246                 rcu_read_unlock();
 247
 248                 if (tx_pkt) {
 249                         /* If the packet originated here, send it out. */
 250                         skb->dev = port->dev;
 251                         skb->pkt_type = pkt_type;
 252                         dev_queue_xmit(skb);
 253                 } else {
 254                         if (consumed)
 255                                 consume_skb(skb);
 256                         else
 257                                 kfree_skb(skb);
 258                 }
 259                 if (dev)
 260                         dev_put(dev);
 261         }
 262 }
 263
 264 static void ipvlan_skb_crossing_ns(struct sk_buff *skb, struct net_device *dev)
 265 {
 266         bool xnet = true;
 267
 268         if (dev)
 269                 xnet = !net_eq(dev_net(skb->dev), dev_net(dev));
 270
 271         skb_scrub_packet(skb, xnet);
 272         if (dev)
 273                 skb->dev = dev;
 274 }
 275
 276 static int ipvlan_rcv_frame(struct ipvl_addr *addr, struct sk_buff **pskb,
 277                             bool local)
 278 {
 279         struct ipvl_dev *ipvlan = addr->master;
 280         struct net_device *dev = ipvlan->dev;
 281         unsigned int len;
 282         rx_handler_result_t ret = RX_HANDLER_CONSUMED;
 283         bool success = false;
 284         struct sk_buff *skb = *pskb;
 285
 286         len = skb->len + ETH_HLEN;
 287         /* Only packets exchanged between two local slaves need to have
 288          * device-up check as well as skb-share check.
 289          */
 290         if (local) {
 291                 if (unlikely(!(dev->flags & IFF_UP))) {
 292                         kfree_skb(skb);
 293                         goto out;
 294                 }
 295
 296                 skb = skb_share_check(skb, GFP_ATOMIC);
 297                 if (!skb)
 298                         goto out;
 299
 300                 *pskb = skb;
 301         }
 302         ipvlan_skb_crossing_ns(skb, dev);
 303
 304         if (local) {
 305                 skb->pkt_type = PACKET_HOST;
 306                 if (dev_forward_skb(ipvlan->dev, skb) == NET_RX_SUCCESS)
 307                         success = true;
 308         } else {
 309                 ret = RX_HANDLER_ANOTHER;
 310                 success = true;
 311         }
 312
 313 out:
 314         ipvlan_count_rx(ipvlan, len, success, false);
 315         return ret;
 316 }
 317
 318 static struct ipvl_addr *ipvlan_addr_lookup(struct ipvl_port *port,
 319                                             void *lyr3h, int addr_type,
 320                                             bool use_dest)
 321 {
 322         struct ipvl_addr *addr = NULL;
 323
 324         if (addr_type == IPVL_IPV6) {
 325                 struct ipv6hdr *ip6h;
 326                 struct in6_addr *i6addr;
 327
 328                 ip6h = (struct ipv6hdr *)lyr3h;
 329                 i6addr = use_dest ? &ip6h->daddr : &ip6h->saddr;
 330                 addr = ipvlan_ht_addr_lookup(port, i6addr, true);
 331         } else if (addr_type == IPVL_ICMPV6) {
 332                 struct nd_msg *ndmh;
 333                 struct in6_addr *i6addr;
 334
 335                 /* Make sure that the NeighborSolicitation ICMPv6 packets
 336                  * are handled to avoid DAD issue.
 337                  */
 338                 ndmh = (struct nd_msg *)lyr3h;
 339                 if (ndmh->icmph.icmp6_type == NDISC_NEIGHBOUR_SOLICITATION) {
 340                         i6addr = &ndmh->target;
 341                         addr = ipvlan_ht_addr_lookup(port, i6addr, true);
 342                 }
 343         } else if (addr_type == IPVL_IPV4) {
 344                 struct iphdr *ip4h;
 345                 __be32 *i4addr;
 346
 347                 ip4h = (struct iphdr *)lyr3h;
 348                 i4addr = use_dest ? &ip4h->daddr : &ip4h->saddr;
 349                 addr = ipvlan_ht_addr_lookup(port, i4addr, false);
 350         } else if (addr_type == IPVL_ARP) {
 351                 struct arphdr *arph;
 352                 unsigned char *arp_ptr;
 353                 __be32 dip;
 354
 355                 arph = (struct arphdr *)lyr3h;
 356                 arp_ptr = (unsigned char *)(arph + 1);
 357                 if (use_dest)
 358                         arp_ptr += (2 * port->dev->addr_len) + 4;
 359                 else
 360                         arp_ptr += port->dev->addr_len;
 361
 362                 memcpy(&dip, arp_ptr, 4);
 363                 addr = ipvlan_ht_addr_lookup(port, &dip, false);
 364         }
 365
 366         return addr;
 367 }
 368
 369 static int ipvlan_process_v4_outbound(struct sk_buff *skb)
 370 {
 371         const struct iphdr *ip4h = ip_hdr(skb);
 372         struct net_device *dev = skb->dev;
 373         struct net *net = dev_net(dev);
 374         struct rtable *rt;
 375         int err, ret = NET_XMIT_DROP;
 376         struct flowi4 fl4 = {
 377                 .flowi4_oif = dev->ifindex,
 378                 .flowi4_tos = RT_TOS(ip4h->tos),
 379                 .flowi4_flags = FLOWI_FLAG_ANYSRC,
 380                 .daddr = ip4h->daddr,
 381                 .saddr = ip4h->saddr,
 382         };
 383
 384         rt = ip_route_output_flow(net, &fl4, NULL);
 385         if (IS_ERR(rt))
 386                 goto err;
 387
 388         if (rt->rt_type != RTN_UNICAST && rt->rt_type != RTN_LOCAL) {
 389                 ip_rt_put(rt);
 390                 goto err;
 391         }
 392         skb_dst_set(skb, &rt->dst);
 393         err = ip_local_out(net, skb->sk, skb);
 394         if (unlikely(net_xmit_eval(err)))
 395                 dev->stats.tx_errors++;
 396         else
 397                 ret = NET_XMIT_SUCCESS;
 398         goto out;
 399 err:
 400         dev->stats.tx_errors++;
 401         kfree_skb(skb);
 402 out:
 403         return ret;
 404 }
 405
 406 static int ipvlan_process_v6_outbound(struct sk_buff *skb)
 407 {
 408         const struct ipv6hdr *ip6h = ipv6_hdr(skb);
 409         struct net_device *dev = skb->dev;
 410         struct net *net = dev_net(dev);
 411         struct dst_entry *dst;
 412         int err, ret = NET_XMIT_DROP;
 413         struct flowi6 fl6 = {
 414                 .flowi6_iif = dev->ifindex,
 415                 .daddr = ip6h->daddr,
 416                 .saddr = ip6h->saddr,
 417                 .flowi6_flags = FLOWI_FLAG_ANYSRC,
 418                 .flowlabel = ip6_flowinfo(ip6h),
 419                 .flowi6_mark = skb->mark,
 420                 .flowi6_proto = ip6h->nexthdr,
 421         };
 422
 423         dst = ip6_route_output(net, NULL, &fl6);
 424         if (dst->error) {
 425                 ret = dst->error;
 426                 dst_release(dst);
 427                 goto err;
 428         }
 429         skb_dst_set(skb, dst);
 430         err = ip6_local_out(net, skb->sk, skb);
 431         if (unlikely(net_xmit_eval(err)))
 432                 dev->stats.tx_errors++;
 433         else
 434                 ret = NET_XMIT_SUCCESS;
 435         goto out;
 436 err:
 437         dev->stats.tx_errors++;
 438         kfree_skb(skb);
 439 out:
 440         return ret;
 441 }
 442
 443 static int ipvlan_process_outbound(struct sk_buff *skb)
 444 {
 445         struct ethhdr *ethh = eth_hdr(skb);
 446         int ret = NET_XMIT_DROP;
 447
 448         /* In this mode we dont care about multicast and broadcast traffic */
 449         if (is_multicast_ether_addr(ethh->h_dest)) {
 450                 pr_warn_ratelimited("Dropped {multi|broad}cast of type= [%x]\n",
 451                                     ntohs(skb->protocol));
 452                 kfree_skb(skb);
 453                 goto out;
 454         }
 455
 456         /* The ipvlan is a pseudo-L2 device, so the packets that we receive
 457          * will have L2; which need to discarded and processed further
 458          * in the net-ns of the main-device.
 459          */
 460         if (skb_mac_header_was_set(skb)) {
 461                 skb_pull(skb, sizeof(*ethh));
 462                 skb->mac_header = (typeof(skb->mac_header))~0U;
 463                 skb_reset_network_header(skb);
 464         }
 465
 466         if (skb->protocol == htons(ETH_P_IPV6))
 467                 ret = ipvlan_process_v6_outbound(skb);
 468         else if (skb->protocol == htons(ETH_P_IP))
 469                 ret = ipvlan_process_v4_outbound(skb);
 470         else {
 471                 pr_warn_ratelimited("Dropped outbound packet type=%x\n",
 472                                     ntohs(skb->protocol));
 473                 kfree_skb(skb);
 474         }
 475 out:
 476         return ret;
 477 }
 478
 479 static void ipvlan_multicast_enqueue(struct ipvl_port *port,
 480                                      struct sk_buff *skb, bool tx_pkt)
 481 {
 482         if (skb->protocol == htons(ETH_P_PAUSE)) {
 483                 kfree_skb(skb);
 484                 return;
 485         }
 486
 487         /* Record that the deferred packet is from TX or RX path. By
 488          * looking at mac-addresses on packet will lead to erronus decisions.
 489          * (This would be true for a loopback-mode on master device or a
 490          * hair-pin mode of the switch.)
 491          */
 492         IPVL_SKB_CB(skb)->tx_pkt = tx_pkt;
 493
 494         spin_lock(&port->backlog.lock);
 495         if (skb_queue_len(&port->backlog) < IPVLAN_QBACKLOG_LIMIT) {
 496                 if (skb->dev)
 497                         dev_hold(skb->dev);
 498                 __skb_queue_tail(&port->backlog, skb);
 499                 spin_unlock(&port->backlog.lock);
 500                 schedule_work(&port->wq);
 501         } else {
 502                 spin_unlock(&port->backlog.lock);
 503                 atomic_long_inc(&skb->dev->rx_dropped);
 504                 kfree_skb(skb);
 505         }
 506 }
 507
 508 static int ipvlan_xmit_mode_l3(struct sk_buff *skb, struct net_device *dev)
 509 {
 510         const struct ipvl_dev *ipvlan = netdev_priv(dev);
 511         void *lyr3h;
 512         struct ipvl_addr *addr;
 513         int addr_type;
 514
 515         lyr3h = ipvlan_get_L3_hdr(skb, &addr_type);
 516         if (!lyr3h)
 517                 goto out;
 518
 519         addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true);
 520         if (addr)
 521                 return ipvlan_rcv_frame(addr, &skb, true);
 522
 523 out:
 524         ipvlan_skb_crossing_ns(skb, ipvlan->phy_dev);
 525         return ipvlan_process_outbound(skb);
 526 }
 527
 528 static int ipvlan_xmit_mode_l2(struct sk_buff *skb, struct net_device *dev)
 529 {
 530         const struct ipvl_dev *ipvlan = netdev_priv(dev);
 531         struct ethhdr *eth = eth_hdr(skb);
 532         struct ipvl_addr *addr;
 533         void *lyr3h;
 534         int addr_type;
 535
 536         if (ether_addr_equal(eth->h_dest, eth->h_source)) {
 537                 lyr3h = ipvlan_get_L3_hdr(skb, &addr_type);
 538                 if (lyr3h) {
 539                         addr = ipvlan_addr_lookup(ipvlan->port, lyr3h, addr_type, true);
 540                         if (addr)
 541                                 return ipvlan_rcv_frame(addr, &skb, true);
 542                 }
 543                 skb = skb_share_check(skb, GFP_ATOMIC);
 544                 if (!skb)
 545                         return NET_XMIT_DROP;
 546
 547                 /* Packet definitely does not belong to any of the
 548                  * virtual devices, but the dest is local. So forward
 549                  * the skb for the main-dev. At the RX side we just return
 550                  * RX_PASS for it to be processed further on the stack.
 551                  */
 552                 return dev_forward_skb(ipvlan->phy_dev, skb);
 553
 554         } else if (is_multicast_ether_addr(eth->h_dest)) {
 555                 ipvlan_skb_crossing_ns(skb, NULL);
 556                 ipvlan_multicast_enqueue(ipvlan->port, skb, true);
 557                 return NET_XMIT_SUCCESS;
 558         }
 559
 560         ipvlan_skb_crossing_ns(skb, ipvlan->phy_dev);
 561         return dev_queue_xmit(skb);
 562 }
 563
 564 int ipvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev)
 565 {
 566         struct ipvl_dev *ipvlan = netdev_priv(dev);
 567         struct ipvl_port *port = ipvlan_port_get_rcu_bh(ipvlan->phy_dev);
 568
 569         if (!port)
 570                 goto out;
 571
 572         if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
 573                 goto out;
 574
 575         switch(port->mode) {
 576         case IPVLAN_MODE_L2:
 577                 return ipvlan_xmit_mode_l2(skb, dev);
 578         case IPVLAN_MODE_L3:
 579         case IPVLAN_MODE_L3S:
 580                 return ipvlan_xmit_mode_l3(skb, dev);
 581         }
 582
 583         /* Should not reach here */
 584         WARN_ONCE(true, "ipvlan_queue_xmit() called for mode = [%hx]\n",
 585                           port->mode);
 586 out:
 587         kfree_skb(skb);
 588         return NET_XMIT_DROP;
 589 }
 590
 591 static bool ipvlan_external_frame(struct sk_buff *skb, struct ipvl_port *port)
 592 {
 593         struct ethhdr *eth = eth_hdr(skb);
 594         struct ipvl_addr *addr;
 595         void *lyr3h;
 596         int addr_type;
 597
 598         if (ether_addr_equal(eth->h_source, skb->dev->dev_addr)) {
 599                 lyr3h = ipvlan_get_L3_hdr(skb, &addr_type);
 600                 if (!lyr3h)
 601                         return true;
 602
 603                 addr = ipvlan_addr_lookup(port, lyr3h, addr_type, false);
 604                 if (addr)
 605                         return false;
 606         }
 607
 608         return true;
 609 }
 610
 611 static rx_handler_result_t ipvlan_handle_mode_l3(struct sk_buff **pskb,
 612                                                  struct ipvl_port *port)
 613 {
 614         void *lyr3h;
 615         int addr_type;
 616         struct ipvl_addr *addr;
 617         struct sk_buff *skb = *pskb;
 618         rx_handler_result_t ret = RX_HANDLER_PASS;
 619
 620         lyr3h = ipvlan_get_L3_hdr(skb, &addr_type);
 621         if (!lyr3h)
 622                 goto out;
 623
 624         addr = ipvlan_addr_lookup(port, lyr3h, addr_type, true);
 625         if (addr)
 626                 ret = ipvlan_rcv_frame(addr, pskb, false);
 627
 628 out:
 629         return ret;
 630 }
 631
 632 static rx_handler_result_t ipvlan_handle_mode_l2(struct sk_buff **pskb,
 633                                                  struct ipvl_port *port)
 634 {
 635         struct sk_buff *skb = *pskb;
 636         struct ethhdr *eth = eth_hdr(skb);
 637         rx_handler_result_t ret = RX_HANDLER_PASS;
 638         void *lyr3h;
 639         int addr_type;
 640
 641         if (is_multicast_ether_addr(eth->h_dest)) {
 642                 if (ipvlan_external_frame(skb, port)) {
 643                         struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
 644
 645                         /* External frames are queued for device local
 646                          * distribution, but a copy is given to master
 647                          * straight away to avoid sending duplicates later
 648                          * when work-queue processes this frame. This is
 649                          * achieved by returning RX_HANDLER_PASS.
 650                          */
 651                         if (nskb) {
 652                                 ipvlan_skb_crossing_ns(nskb, NULL);
 653                                 ipvlan_multicast_enqueue(port, nskb, false);
 654                         }
 655                 }
 656         } else {
 657                 struct ipvl_addr *addr;
 658
 659                 lyr3h = ipvlan_get_L3_hdr(skb, &addr_type);
 660                 if (!lyr3h)
 661                         return ret;
 662
 663                 addr = ipvlan_addr_lookup(port, lyr3h, addr_type, true);
 664                 if (addr)
 665                         ret = ipvlan_rcv_frame(addr, pskb, false);
 666         }
 667
 668         return ret;
 669 }
 670
 671 rx_handler_result_t ipvlan_handle_frame(struct sk_buff **pskb)
 672 {
 673         struct sk_buff *skb = *pskb;
 674         struct ipvl_port *port = ipvlan_port_get_rcu(skb->dev);
 675
 676         if (!port)
 677                 return RX_HANDLER_PASS;
 678
 679         switch (port->mode) {
 680         case IPVLAN_MODE_L2:
 681                 return ipvlan_handle_mode_l2(pskb, port);
 682         case IPVLAN_MODE_L3:
 683                 return ipvlan_handle_mode_l3(pskb, port);
 684         case IPVLAN_MODE_L3S:
 685                 return RX_HANDLER_PASS;
 686         }
 687
 688         /* Should not reach here */
 689         WARN_ONCE(true, "ipvlan_handle_frame() called for mode = [%hx]\n",
 690                           port->mode);
 691         kfree_skb(skb);
 692         return RX_HANDLER_CONSUMED;
 693 }
 694
 695 static struct ipvl_addr *ipvlan_skb_to_addr(struct sk_buff *skb,
 696                                             struct net_device *dev)
 697 {
 698         struct ipvl_addr *addr = NULL;
 699         struct ipvl_port *port;
 700         void *lyr3h;
 701         int addr_type;
 702
 703         if (!dev || !netif_is_ipvlan_port(dev))
 704                 goto out;
 705
 706         port = ipvlan_port_get_rcu(dev);
 707         if (!port || port->mode != IPVLAN_MODE_L3S)
 708                 goto out;
 709
 710         lyr3h = ipvlan_get_L3_hdr(skb, &addr_type);
 711         if (!lyr3h)
 712                 goto out;
 713
 714         addr = ipvlan_addr_lookup(port, lyr3h, addr_type, true);
 715 out:
 716         return addr;
 717 }
 718
 719 struct sk_buff *ipvlan_l3_rcv(struct net_device *dev, struct sk_buff *skb,
 720                               u16 proto)
 721 {
 722         struct ipvl_addr *addr;
 723         struct net_device *sdev;
 724
 725         addr = ipvlan_skb_to_addr(skb, dev);
 726         if (!addr)
 727                 goto out;
 728
 729         sdev = addr->master->dev;
 730         switch (proto) {
 731         case AF_INET:
 732         {
 733                 int err;
 734                 struct iphdr *ip4h = ip_hdr(skb);
 735
 736                 err = ip_route_input_noref(skb, ip4h->daddr, ip4h->saddr,
 737                                            ip4h->tos, sdev);
 738                 if (unlikely(err))
 739                         goto out;
 740                 break;
 741         }
 742         case AF_INET6:
 743         {
 744                 struct dst_entry *dst;
 745                 struct ipv6hdr *ip6h = ipv6_hdr(skb);
 746                 int flags = RT6_LOOKUP_F_HAS_SADDR;
 747                 struct flowi6 fl6 = {
 748                         .flowi6_iif   = sdev->ifindex,
 749                         .daddr        = ip6h->daddr,
 750                         .saddr        = ip6h->saddr,
 751                         .flowlabel    = ip6_flowinfo(ip6h),
 752                         .flowi6_mark  = skb->mark,
 753                         .flowi6_proto = ip6h->nexthdr,
 754                 };
 755
 756                 skb_dst_drop(skb);
 757                 dst = ip6_route_input_lookup(dev_net(sdev), sdev, &fl6, flags);
 758                 skb_dst_set(skb, dst);
 759                 break;
 760         }
 761         default:
 762                 break;
 763         }
 764
 765 out:
 766         return skb;
 767 }
 768
 769 unsigned int ipvlan_nf_input(void *priv, struct sk_buff *skb,
 770                              const struct nf_hook_state *state)
 771 {
 772         struct ipvl_addr *addr;
 773         unsigned int len;
 774
 775         addr = ipvlan_skb_to_addr(skb, skb->dev);
 776         if (!addr)
 777                 goto out;
 778
 779         skb->dev = addr->master->dev;
 780         len = skb->len + ETH_HLEN;
 781         ipvlan_count_rx(addr->master, len, true, false);
 782 out:
 783         return NF_ACCEPT;
 784 }