drivers/net/macvlan.c

   1 /*
   2  * Copyright (c) 2007 Patrick McHardy <kaber@trash.net>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of
   7  * the License, or (at your option) any later version.
   8  *
   9  * The code this is based on carried the following copyright notice:
  10  * ---
  11  * (C) Copyright 2001-2006
  12  * Alex Zeffertt, Cambridge Broadband Ltd, ajz@cambridgebroadband.com
  13  * Re-worked by Ben Greear <greearb@candelatech.com>
  14  * ---
  15  */
  16 #include <linux/kernel.h>
  17 #include <linux/types.h>
  18 #include <linux/module.h>
  19 #include <linux/init.h>
  20 #include <linux/errno.h>
  21 #include <linux/slab.h>
  22 #include <linux/string.h>
  23 #include <linux/rculist.h>
  24 #include <linux/notifier.h>
  25 #include <linux/netdevice.h>
  26 #include <linux/etherdevice.h>
  27 #include <linux/ethtool.h>
  28 #include <linux/if_arp.h>
  29 #include <linux/if_link.h>
  30 #include <linux/if_macvlan.h>
  31 #include <net/rtnetlink.h>
  32 #include <net/xfrm.h>
  33
  34 #define MACVLAN_HASH_SIZE       (1 << BITS_PER_BYTE)
  35
  36 struct macvlan_port {
  37         struct net_device       *dev;
  38         struct hlist_head       vlan_hash[MACVLAN_HASH_SIZE];
  39         struct list_head        vlans;
  40         struct rcu_head         rcu;
  41         bool                    passthru;
  42         int                     count;
  43 };
  44
  45 static void macvlan_port_destroy(struct net_device *dev);
  46
  47 #define macvlan_port_get_rcu(dev) \
  48         ((struct macvlan_port *) rcu_dereference(dev->rx_handler_data))
  49 #define macvlan_port_get(dev) ((struct macvlan_port *) dev->rx_handler_data)
  50 #define macvlan_port_exists(dev) (dev->priv_flags & IFF_MACVLAN_PORT)
  51
  52 static struct macvlan_dev *macvlan_hash_lookup(const struct macvlan_port *port,
  53                                                const unsigned char *addr)
  54 {
  55         struct macvlan_dev *vlan;
  56         struct hlist_node *n;
  57
  58         hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[addr[5]], hlist) {
  59                 if (!compare_ether_addr_64bits(vlan->dev->dev_addr, addr))
  60                         return vlan;
  61         }
  62         return NULL;
  63 }
  64
  65 static void macvlan_hash_add(struct macvlan_dev *vlan)
  66 {
  67         struct macvlan_port *port = vlan->port;
  68         const unsigned char *addr = vlan->dev->dev_addr;
  69
  70         hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[addr[5]]);
  71 }
  72
  73 static void macvlan_hash_del(struct macvlan_dev *vlan, bool sync)
  74 {
  75         hlist_del_rcu(&vlan->hlist);
  76         if (sync)
  77                 synchronize_rcu();
  78 }
  79
  80 static void macvlan_hash_change_addr(struct macvlan_dev *vlan,
  81                                         const unsigned char *addr)
  82 {
  83         macvlan_hash_del(vlan, true);
  84         /* Now that we are unhashed it is safe to change the device
  85          * address without confusing packet delivery.
  86          */
  87         memcpy(vlan->dev->dev_addr, addr, ETH_ALEN);
  88         macvlan_hash_add(vlan);
  89 }
  90
  91 static int macvlan_addr_busy(const struct macvlan_port *port,
  92                                 const unsigned char *addr)
  93 {
  94         /* Test to see if the specified multicast address is
  95          * currently in use by the underlying device or
  96          * another macvlan.
  97          */
  98         if (!compare_ether_addr_64bits(port->dev->dev_addr, addr))
  99                 return 1;
 100
 101         if (macvlan_hash_lookup(port, addr))
 102                 return 1;
 103
 104         return 0;
 105 }
 106
 107
 108 static int macvlan_broadcast_one(struct sk_buff *skb,
 109                                  const struct macvlan_dev *vlan,
 110                                  const struct ethhdr *eth, bool local)
 111 {
 112         struct net_device *dev = vlan->dev;
 113         if (!skb)
 114                 return NET_RX_DROP;
 115
 116         if (local)
 117                 return vlan->forward(dev, skb);
 118
 119         skb->dev = dev;
 120         if (!compare_ether_addr_64bits(eth->h_dest,
 121                                        dev->broadcast))
 122                 skb->pkt_type = PACKET_BROADCAST;
 123         else
 124                 skb->pkt_type = PACKET_MULTICAST;
 125
 126         return vlan->receive(skb);
 127 }
 128
 129 static void macvlan_broadcast(struct sk_buff *skb,
 130                               const struct macvlan_port *port,
 131                               struct net_device *src,
 132                               enum macvlan_mode mode)
 133 {
 134         const struct ethhdr *eth = eth_hdr(skb);
 135         const struct macvlan_dev *vlan;
 136         struct hlist_node *n;
 137         struct sk_buff *nskb;
 138         unsigned int i;
 139         int err;
 140
 141         if (skb->protocol == htons(ETH_P_PAUSE))
 142                 return;
 143
 144         for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
 145                 hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
 146                         if (vlan->dev == src || !(vlan->mode & mode))
 147                                 continue;
 148
 149                         nskb = skb_clone(skb, GFP_ATOMIC);
 150                         err = macvlan_broadcast_one(nskb, vlan, eth,
 151                                          mode == MACVLAN_MODE_BRIDGE);
 152                         macvlan_count_rx(vlan, skb->len + ETH_HLEN,
 153                                          err == NET_RX_SUCCESS, 1);
 154                 }
 155         }
 156 }
 157
 158 /* called under rcu_read_lock() from netif_receive_skb */
 159 static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb)
 160 {
 161         struct macvlan_port *port;
 162         struct sk_buff *skb = *pskb;
 163         const struct ethhdr *eth = eth_hdr(skb);
 164         const struct macvlan_dev *vlan;
 165         const struct macvlan_dev *src;
 166         struct net_device *dev;
 167         unsigned int len = 0;
 168         int ret = NET_RX_DROP;
 169
 170         port = macvlan_port_get_rcu(skb->dev);
 171         if (is_multicast_ether_addr(eth->h_dest)) {
 172                 skb = ip_check_defrag(skb, IP_DEFRAG_MACVLAN);
 173                 if (!skb)
 174                         return RX_HANDLER_CONSUMED;
 175                 src = macvlan_hash_lookup(port, eth->h_source);
 176                 if (!src)
 177                         /* frame comes from an external address */
 178                         macvlan_broadcast(skb, port, NULL,
 179                                           MACVLAN_MODE_PRIVATE |
 180                                           MACVLAN_MODE_VEPA    |
 181                                           MACVLAN_MODE_PASSTHRU|
 182                                           MACVLAN_MODE_BRIDGE);
 183                 else if (src->mode == MACVLAN_MODE_VEPA)
 184                         /* flood to everyone except source */
 185                         macvlan_broadcast(skb, port, src->dev,
 186                                           MACVLAN_MODE_VEPA |
 187                                           MACVLAN_MODE_BRIDGE);
 188                 else if (src->mode == MACVLAN_MODE_BRIDGE)
 189                         /*
 190                          * flood only to VEPA ports, bridge ports
 191                          * already saw the frame on the way out.
 192                          */
 193                         macvlan_broadcast(skb, port, src->dev,
 194                                           MACVLAN_MODE_VEPA);
 195                 return RX_HANDLER_PASS;
 196         }
 197
 198         if (port->passthru)
 199                 vlan = list_first_entry(&port->vlans, struct macvlan_dev, list);
 200         else
 201                 vlan = macvlan_hash_lookup(port, eth->h_dest);
 202         if (vlan == NULL)
 203                 return RX_HANDLER_PASS;
 204
 205         dev = vlan->dev;
 206         if (unlikely(!(dev->flags & IFF_UP))) {
 207                 kfree_skb(skb);
 208                 return RX_HANDLER_CONSUMED;
 209         }
 210         len = skb->len + ETH_HLEN;
 211         skb = skb_share_check(skb, GFP_ATOMIC);
 212         if (!skb)
 213                 goto out;
 214
 215         skb->dev = dev;
 216         skb->pkt_type = PACKET_HOST;
 217
 218         ret = vlan->receive(skb);
 219
 220 out:
 221         macvlan_count_rx(vlan, len, ret == NET_RX_SUCCESS, 0);
 222         return RX_HANDLER_CONSUMED;
 223 }
 224
 225 static int macvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev)
 226 {
 227         const struct macvlan_dev *vlan = netdev_priv(dev);
 228         const struct macvlan_port *port = vlan->port;
 229         const struct macvlan_dev *dest;
 230         __u8 ip_summed = skb->ip_summed;
 231
 232         if (vlan->mode == MACVLAN_MODE_BRIDGE) {
 233                 const struct ethhdr *eth = (void *)skb->data;
 234                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 235
 236                 /* send to other bridge ports directly */
 237                 if (is_multicast_ether_addr(eth->h_dest)) {
 238                         macvlan_broadcast(skb, port, dev, MACVLAN_MODE_BRIDGE);
 239                         goto xmit_world;
 240                 }
 241
 242                 dest = macvlan_hash_lookup(port, eth->h_dest);
 243                 if (dest && dest->mode == MACVLAN_MODE_BRIDGE) {
 244                         /* send to lowerdev first for its network taps */
 245                         dev_forward_skb(vlan->lowerdev, skb);
 246
 247                         return NET_XMIT_SUCCESS;
 248                 }
 249         }
 250
 251 xmit_world:
 252         skb->ip_summed = ip_summed;
 253         skb_set_dev(skb, vlan->lowerdev);
 254         return dev_queue_xmit(skb);
 255 }
 256
 257 netdev_tx_t macvlan_start_xmit(struct sk_buff *skb,
 258                                struct net_device *dev)
 259 {
 260         unsigned int len = skb->len;
 261         int ret;
 262         const struct macvlan_dev *vlan = netdev_priv(dev);
 263
 264         ret = macvlan_queue_xmit(skb, dev);
 265         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 266                 struct macvlan_pcpu_stats *pcpu_stats;
 267
 268                 pcpu_stats = this_cpu_ptr(vlan->pcpu_stats);
 269                 u64_stats_update_begin(&pcpu_stats->syncp);
 270                 pcpu_stats->tx_packets++;
 271                 pcpu_stats->tx_bytes += len;
 272                 u64_stats_update_end(&pcpu_stats->syncp);
 273         } else {
 274                 this_cpu_inc(vlan->pcpu_stats->tx_dropped);
 275         }
 276         return ret;
 277 }
 278 EXPORT_SYMBOL_GPL(macvlan_start_xmit);
 279
 280 static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
 281                                unsigned short type, const void *daddr,
 282                                const void *saddr, unsigned len)
 283 {
 284         const struct macvlan_dev *vlan = netdev_priv(dev);
 285         struct net_device *lowerdev = vlan->lowerdev;
 286
 287         return dev_hard_header(skb, lowerdev, type, daddr,
 288                                saddr ? : dev->dev_addr, len);
 289 }
 290
 291 static const struct header_ops macvlan_hard_header_ops = {
 292         .create         = macvlan_hard_header,
 293         .rebuild        = eth_rebuild_header,
 294         .parse          = eth_header_parse,
 295         .cache          = eth_header_cache,
 296         .cache_update   = eth_header_cache_update,
 297 };
 298
 299 static int macvlan_open(struct net_device *dev)
 300 {
 301         struct macvlan_dev *vlan = netdev_priv(dev);
 302         struct net_device *lowerdev = vlan->lowerdev;
 303         int err;
 304
 305         if (vlan->port->passthru) {
 306                 dev_set_promiscuity(lowerdev, 1);
 307                 goto hash_add;
 308         }
 309
 310         err = -EBUSY;
 311         if (macvlan_addr_busy(vlan->port, dev->dev_addr))
 312                 goto out;
 313
 314         err = dev_uc_add(lowerdev, dev->dev_addr);
 315         if (err < 0)
 316                 goto out;
 317         if (dev->flags & IFF_ALLMULTI) {
 318                 err = dev_set_allmulti(lowerdev, 1);
 319                 if (err < 0)
 320                         goto del_unicast;
 321         }
 322
 323 hash_add:
 324         macvlan_hash_add(vlan);
 325         return 0;
 326
 327 del_unicast:
 328         dev_uc_del(lowerdev, dev->dev_addr);
 329 out:
 330         return err;
 331 }
 332
 333 static int macvlan_stop(struct net_device *dev)
 334 {
 335         struct macvlan_dev *vlan = netdev_priv(dev);
 336         struct net_device *lowerdev = vlan->lowerdev;
 337
 338         if (vlan->port->passthru) {
 339                 dev_set_promiscuity(lowerdev, -1);
 340                 goto hash_del;
 341         }
 342
 343         dev_mc_unsync(lowerdev, dev);
 344         if (dev->flags & IFF_ALLMULTI)
 345                 dev_set_allmulti(lowerdev, -1);
 346
 347         dev_uc_del(lowerdev, dev->dev_addr);
 348
 349 hash_del:
 350         macvlan_hash_del(vlan, !dev->dismantle);
 351         return 0;
 352 }
 353
 354 static int macvlan_set_mac_address(struct net_device *dev, void *p)
 355 {
 356         struct macvlan_dev *vlan = netdev_priv(dev);
 357         struct net_device *lowerdev = vlan->lowerdev;
 358         struct sockaddr *addr = p;
 359         int err;
 360
 361         if (!is_valid_ether_addr(addr->sa_data))
 362                 return -EADDRNOTAVAIL;
 363
 364         if (!(dev->flags & IFF_UP)) {
 365                 /* Just copy in the new address */
 366                 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 367         } else {
 368                 /* Rehash and update the device filters */
 369                 if (macvlan_addr_busy(vlan->port, addr->sa_data))
 370                         return -EBUSY;
 371
 372                 err = dev_uc_add(lowerdev, addr->sa_data);
 373                 if (err)
 374                         return err;
 375
 376                 dev_uc_del(lowerdev, dev->dev_addr);
 377
 378                 macvlan_hash_change_addr(vlan, addr->sa_data);
 379         }
 380         return 0;
 381 }
 382
 383 static void macvlan_change_rx_flags(struct net_device *dev, int change)
 384 {
 385         struct macvlan_dev *vlan = netdev_priv(dev);
 386         struct net_device *lowerdev = vlan->lowerdev;
 387
 388         if (change & IFF_ALLMULTI)
 389                 dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
 390 }
 391
 392 static void macvlan_set_multicast_list(struct net_device *dev)
 393 {
 394         struct macvlan_dev *vlan = netdev_priv(dev);
 395
 396         dev_mc_sync(vlan->lowerdev, dev);
 397 }
 398
 399 static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
 400 {
 401         struct macvlan_dev *vlan = netdev_priv(dev);
 402
 403         if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
 404                 return -EINVAL;
 405         dev->mtu = new_mtu;
 406         return 0;
 407 }
 408
 409 /*
 410  * macvlan network devices have devices nesting below it and are a special
 411  * "super class" of normal network devices; split their locks off into a
 412  * separate class since they always nest.
 413  */
 414 static struct lock_class_key macvlan_netdev_xmit_lock_key;
 415 static struct lock_class_key macvlan_netdev_addr_lock_key;
 416
 417 #define MACVLAN_FEATURES \
 418         (NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
 419          NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
 420          NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM | \
 421          NETIF_F_HW_VLAN_FILTER)
 422
 423 #define MACVLAN_STATE_MASK \
 424         ((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
 425
 426 static void macvlan_set_lockdep_class_one(struct net_device *dev,
 427                                           struct netdev_queue *txq,
 428                                           void *_unused)
 429 {
 430         lockdep_set_class(&txq->_xmit_lock,
 431                           &macvlan_netdev_xmit_lock_key);
 432 }
 433
 434 static void macvlan_set_lockdep_class(struct net_device *dev)
 435 {
 436         lockdep_set_class(&dev->addr_list_lock,
 437                           &macvlan_netdev_addr_lock_key);
 438         netdev_for_each_tx_queue(dev, macvlan_set_lockdep_class_one, NULL);
 439 }
 440
 441 static int macvlan_init(struct net_device *dev)
 442 {
 443         struct macvlan_dev *vlan = netdev_priv(dev);
 444         const struct net_device *lowerdev = vlan->lowerdev;
 445
 446         dev->state              = (dev->state & ~MACVLAN_STATE_MASK) |
 447                                   (lowerdev->state & MACVLAN_STATE_MASK);
 448         dev->features           = lowerdev->features & MACVLAN_FEATURES;
 449         dev->features           |= NETIF_F_LLTX;
 450         dev->gso_max_size       = lowerdev->gso_max_size;
 451         dev->iflink             = lowerdev->ifindex;
 452         dev->hard_header_len    = lowerdev->hard_header_len;
 453
 454         macvlan_set_lockdep_class(dev);
 455
 456         vlan->pcpu_stats = alloc_percpu(struct macvlan_pcpu_stats);
 457         if (!vlan->pcpu_stats)
 458                 return -ENOMEM;
 459
 460         return 0;
 461 }
 462
 463 static void macvlan_uninit(struct net_device *dev)
 464 {
 465         struct macvlan_dev *vlan = netdev_priv(dev);
 466         struct macvlan_port *port = vlan->port;
 467
 468         free_percpu(vlan->pcpu_stats);
 469
 470         port->count -= 1;
 471         if (!port->count)
 472                 macvlan_port_destroy(port->dev);
 473 }
 474
 475 static struct rtnl_link_stats64 *macvlan_dev_get_stats64(struct net_device *dev,
 476                                                          struct rtnl_link_stats64 *stats)
 477 {
 478         struct macvlan_dev *vlan = netdev_priv(dev);
 479
 480         if (vlan->pcpu_stats) {
 481                 struct macvlan_pcpu_stats *p;
 482                 u64 rx_packets, rx_bytes, rx_multicast, tx_packets, tx_bytes;
 483                 u32 rx_errors = 0, tx_dropped = 0;
 484                 unsigned int start;
 485                 int i;
 486
 487                 for_each_possible_cpu(i) {
 488                         p = per_cpu_ptr(vlan->pcpu_stats, i);
 489                         do {
 490                                 start = u64_stats_fetch_begin_bh(&p->syncp);
 491                                 rx_packets      = p->rx_packets;
 492                                 rx_bytes        = p->rx_bytes;
 493                                 rx_multicast    = p->rx_multicast;
 494                                 tx_packets      = p->tx_packets;
 495                                 tx_bytes        = p->tx_bytes;
 496                         } while (u64_stats_fetch_retry_bh(&p->syncp, start));
 497
 498                         stats->rx_packets       += rx_packets;
 499                         stats->rx_bytes         += rx_bytes;
 500                         stats->multicast        += rx_multicast;
 501                         stats->tx_packets       += tx_packets;
 502                         stats->tx_bytes         += tx_bytes;
 503                         /* rx_errors & tx_dropped are u32, updated
 504                          * without syncp protection.
 505                          */
 506                         rx_errors       += p->rx_errors;
 507                         tx_dropped      += p->tx_dropped;
 508                 }
 509                 stats->rx_errors        = rx_errors;
 510                 stats->rx_dropped       = rx_errors;
 511                 stats->tx_dropped       = tx_dropped;
 512         }
 513         return stats;
 514 }
 515
 516 static void macvlan_vlan_rx_add_vid(struct net_device *dev,
 517                                     unsigned short vid)
 518 {
 519         struct macvlan_dev *vlan = netdev_priv(dev);
 520         struct net_device *lowerdev = vlan->lowerdev;
 521         const struct net_device_ops *ops = lowerdev->netdev_ops;
 522
 523         if (ops->ndo_vlan_rx_add_vid)
 524                 ops->ndo_vlan_rx_add_vid(lowerdev, vid);
 525 }
 526
 527 static void macvlan_vlan_rx_kill_vid(struct net_device *dev,
 528                                      unsigned short vid)
 529 {
 530         struct macvlan_dev *vlan = netdev_priv(dev);
 531         struct net_device *lowerdev = vlan->lowerdev;
 532         const struct net_device_ops *ops = lowerdev->netdev_ops;
 533
 534         if (ops->ndo_vlan_rx_kill_vid)
 535                 ops->ndo_vlan_rx_kill_vid(lowerdev, vid);
 536 }
 537
 538 static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
 539                                         struct ethtool_drvinfo *drvinfo)
 540 {
 541         snprintf(drvinfo->driver, 32, "macvlan");
 542         snprintf(drvinfo->version, 32, "0.1");
 543 }
 544
 545 static int macvlan_ethtool_get_settings(struct net_device *dev,
 546                                         struct ethtool_cmd *cmd)
 547 {
 548         const struct macvlan_dev *vlan = netdev_priv(dev);
 549
 550         return __ethtool_get_settings(vlan->lowerdev, cmd);
 551 }
 552
 553 static const struct ethtool_ops macvlan_ethtool_ops = {
 554         .get_link               = ethtool_op_get_link,
 555         .get_settings           = macvlan_ethtool_get_settings,
 556         .get_drvinfo            = macvlan_ethtool_get_drvinfo,
 557 };
 558
 559 static const struct net_device_ops macvlan_netdev_ops = {
 560         .ndo_init               = macvlan_init,
 561         .ndo_uninit             = macvlan_uninit,
 562         .ndo_open               = macvlan_open,
 563         .ndo_stop               = macvlan_stop,
 564         .ndo_start_xmit         = macvlan_start_xmit,
 565         .ndo_change_mtu         = macvlan_change_mtu,
 566         .ndo_change_rx_flags    = macvlan_change_rx_flags,
 567         .ndo_set_mac_address    = macvlan_set_mac_address,
 568         .ndo_set_rx_mode        = macvlan_set_multicast_list,
 569         .ndo_get_stats64        = macvlan_dev_get_stats64,
 570         .ndo_validate_addr      = eth_validate_addr,
 571         .ndo_vlan_rx_add_vid    = macvlan_vlan_rx_add_vid,
 572         .ndo_vlan_rx_kill_vid   = macvlan_vlan_rx_kill_vid,
 573 };
 574
 575 void macvlan_common_setup(struct net_device *dev)
 576 {
 577         ether_setup(dev);
 578
 579         dev->priv_flags        &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
 580         dev->netdev_ops         = &macvlan_netdev_ops;
 581         dev->destructor         = free_netdev;
 582         dev->header_ops         = &macvlan_hard_header_ops,
 583         dev->ethtool_ops        = &macvlan_ethtool_ops;
 584 }
 585 EXPORT_SYMBOL_GPL(macvlan_common_setup);
 586
 587 static void macvlan_setup(struct net_device *dev)
 588 {
 589         macvlan_common_setup(dev);
 590         dev->tx_queue_len       = 0;
 591 }
 592
 593 static int macvlan_port_create(struct net_device *dev)
 594 {
 595         struct macvlan_port *port;
 596         unsigned int i;
 597         int err;
 598
 599         if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
 600                 return -EINVAL;
 601
 602         port = kzalloc(sizeof(*port), GFP_KERNEL);
 603         if (port == NULL)
 604                 return -ENOMEM;
 605
 606         port->passthru = false;
 607         port->dev = dev;
 608         INIT_LIST_HEAD(&port->vlans);
 609         for (i = 0; i < MACVLAN_HASH_SIZE; i++)
 610                 INIT_HLIST_HEAD(&port->vlan_hash[i]);
 611
 612         err = netdev_rx_handler_register(dev, macvlan_handle_frame, port);
 613         if (err)
 614                 kfree(port);
 615         else
 616                 dev->priv_flags |= IFF_MACVLAN_PORT;
 617         return err;
 618 }
 619
 620 static void macvlan_port_destroy(struct net_device *dev)
 621 {
 622         struct macvlan_port *port = macvlan_port_get(dev);
 623
 624         dev->priv_flags &= ~IFF_MACVLAN_PORT;
 625         netdev_rx_handler_unregister(dev);
 626         kfree_rcu(port, rcu);
 627 }
 628
 629 static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
 630 {
 631         if (tb[IFLA_ADDRESS]) {
 632                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
 633                         return -EINVAL;
 634                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
 635                         return -EADDRNOTAVAIL;
 636         }
 637
 638         if (data && data[IFLA_MACVLAN_MODE]) {
 639                 switch (nla_get_u32(data[IFLA_MACVLAN_MODE])) {
 640                 case MACVLAN_MODE_PRIVATE:
 641                 case MACVLAN_MODE_VEPA:
 642                 case MACVLAN_MODE_BRIDGE:
 643                 case MACVLAN_MODE_PASSTHRU:
 644                         break;
 645                 default:
 646                         return -EINVAL;
 647                 }
 648         }
 649         return 0;
 650 }
 651
 652 int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
 653                            struct nlattr *tb[], struct nlattr *data[],
 654                            int (*receive)(struct sk_buff *skb),
 655                            int (*forward)(struct net_device *dev,
 656                                           struct sk_buff *skb))
 657 {
 658         struct macvlan_dev *vlan = netdev_priv(dev);
 659         struct macvlan_port *port;
 660         struct net_device *lowerdev;
 661         int err;
 662
 663         if (!tb[IFLA_LINK])
 664                 return -EINVAL;
 665
 666         lowerdev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
 667         if (lowerdev == NULL)
 668                 return -ENODEV;
 669
 670         /* When creating macvlans on top of other macvlans - use
 671          * the real device as the lowerdev.
 672          */
 673         if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops) {
 674                 struct macvlan_dev *lowervlan = netdev_priv(lowerdev);
 675                 lowerdev = lowervlan->lowerdev;
 676         }
 677
 678         if (!tb[IFLA_MTU])
 679                 dev->mtu = lowerdev->mtu;
 680         else if (dev->mtu > lowerdev->mtu)
 681                 return -EINVAL;
 682
 683         if (!tb[IFLA_ADDRESS])
 684                 random_ether_addr(dev->dev_addr);
 685
 686         if (!macvlan_port_exists(lowerdev)) {
 687                 err = macvlan_port_create(lowerdev);
 688                 if (err < 0)
 689                         return err;
 690         }
 691         port = macvlan_port_get(lowerdev);
 692
 693         /* Only 1 macvlan device can be created in passthru mode */
 694         if (port->passthru)
 695                 return -EINVAL;
 696
 697         vlan->lowerdev = lowerdev;
 698         vlan->dev      = dev;
 699         vlan->port     = port;
 700         vlan->receive  = receive;
 701         vlan->forward  = forward;
 702
 703         vlan->mode     = MACVLAN_MODE_VEPA;
 704         if (data && data[IFLA_MACVLAN_MODE])
 705                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
 706
 707         if (vlan->mode == MACVLAN_MODE_PASSTHRU) {
 708                 if (port->count)
 709                         return -EINVAL;
 710                 port->passthru = true;
 711                 memcpy(dev->dev_addr, lowerdev->dev_addr, ETH_ALEN);
 712         }
 713
 714         port->count += 1;
 715         err = register_netdevice(dev);
 716         if (err < 0)
 717                 goto destroy_port;
 718
 719         list_add_tail(&vlan->list, &port->vlans);
 720         netif_stacked_transfer_operstate(lowerdev, dev);
 721
 722         return 0;
 723
 724 destroy_port:
 725         port->count -= 1;
 726         if (!port->count)
 727                 macvlan_port_destroy(lowerdev);
 728
 729         return err;
 730 }
 731 EXPORT_SYMBOL_GPL(macvlan_common_newlink);
 732
 733 static int macvlan_newlink(struct net *src_net, struct net_device *dev,
 734                            struct nlattr *tb[], struct nlattr *data[])
 735 {
 736         return macvlan_common_newlink(src_net, dev, tb, data,
 737                                       netif_rx,
 738                                       dev_forward_skb);
 739 }
 740
 741 void macvlan_dellink(struct net_device *dev, struct list_head *head)
 742 {
 743         struct macvlan_dev *vlan = netdev_priv(dev);
 744
 745         list_del(&vlan->list);
 746         unregister_netdevice_queue(dev, head);
 747 }
 748 EXPORT_SYMBOL_GPL(macvlan_dellink);
 749
 750 static int macvlan_changelink(struct net_device *dev,
 751                 struct nlattr *tb[], struct nlattr *data[])
 752 {
 753         struct macvlan_dev *vlan = netdev_priv(dev);
 754         if (data && data[IFLA_MACVLAN_MODE])
 755                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
 756         return 0;
 757 }
 758
 759 static size_t macvlan_get_size(const struct net_device *dev)
 760 {
 761         return nla_total_size(4);
 762 }
 763
 764 static int macvlan_fill_info(struct sk_buff *skb,
 765                                 const struct net_device *dev)
 766 {
 767         struct macvlan_dev *vlan = netdev_priv(dev);
 768
 769         NLA_PUT_U32(skb, IFLA_MACVLAN_MODE, vlan->mode);
 770         return 0;
 771
 772 nla_put_failure:
 773         return -EMSGSIZE;
 774 }
 775
 776 static const struct nla_policy macvlan_policy[IFLA_MACVLAN_MAX + 1] = {
 777         [IFLA_MACVLAN_MODE] = { .type = NLA_U32 },
 778 };
 779
 780 int macvlan_link_register(struct rtnl_link_ops *ops)
 781 {
 782         /* common fields */
 783         ops->priv_size          = sizeof(struct macvlan_dev);
 784         ops->validate           = macvlan_validate;
 785         ops->maxtype            = IFLA_MACVLAN_MAX;
 786         ops->policy             = macvlan_policy;
 787         ops->changelink         = macvlan_changelink;
 788         ops->get_size           = macvlan_get_size;
 789         ops->fill_info          = macvlan_fill_info;
 790
 791         return rtnl_link_register(ops);
 792 };
 793 EXPORT_SYMBOL_GPL(macvlan_link_register);
 794
 795 static struct rtnl_link_ops macvlan_link_ops = {
 796         .kind           = "macvlan",
 797         .setup          = macvlan_setup,
 798         .newlink        = macvlan_newlink,
 799         .dellink        = macvlan_dellink,
 800 };
 801
 802 static int macvlan_device_event(struct notifier_block *unused,
 803                                 unsigned long event, void *ptr)
 804 {
 805         struct net_device *dev = ptr;
 806         struct macvlan_dev *vlan, *next;
 807         struct macvlan_port *port;
 808         LIST_HEAD(list_kill);
 809
 810         if (!macvlan_port_exists(dev))
 811                 return NOTIFY_DONE;
 812
 813         port = macvlan_port_get(dev);
 814
 815         switch (event) {
 816         case NETDEV_CHANGE:
 817                 list_for_each_entry(vlan, &port->vlans, list)
 818                         netif_stacked_transfer_operstate(vlan->lowerdev,
 819                                                          vlan->dev);
 820                 break;
 821         case NETDEV_FEAT_CHANGE:
 822                 list_for_each_entry(vlan, &port->vlans, list) {
 823                         vlan->dev->features = dev->features & MACVLAN_FEATURES;
 824                         vlan->dev->gso_max_size = dev->gso_max_size;
 825                         netdev_features_change(vlan->dev);
 826                 }
 827                 break;
 828         case NETDEV_UNREGISTER:
 829                 /* twiddle thumbs on netns device moves */
 830                 if (dev->reg_state != NETREG_UNREGISTERING)
 831                         break;
 832
 833                 list_for_each_entry_safe(vlan, next, &port->vlans, list)
 834                         vlan->dev->rtnl_link_ops->dellink(vlan->dev, &list_kill);
 835                 unregister_netdevice_many(&list_kill);
 836                 list_del(&list_kill);
 837                 break;
 838         case NETDEV_PRE_TYPE_CHANGE:
 839                 /* Forbid underlaying device to change its type. */
 840                 return NOTIFY_BAD;
 841         }
 842         return NOTIFY_DONE;
 843 }
 844
 845 static struct notifier_block macvlan_notifier_block __read_mostly = {
 846         .notifier_call  = macvlan_device_event,
 847 };
 848
 849 static int __init macvlan_init_module(void)
 850 {
 851         int err;
 852
 853         register_netdevice_notifier(&macvlan_notifier_block);
 854
 855         err = macvlan_link_register(&macvlan_link_ops);
 856         if (err < 0)
 857                 goto err1;
 858         return 0;
 859 err1:
 860         unregister_netdevice_notifier(&macvlan_notifier_block);
 861         return err;
 862 }
 863
 864 static void __exit macvlan_cleanup_module(void)
 865 {
 866         rtnl_link_unregister(&macvlan_link_ops);
 867         unregister_netdevice_notifier(&macvlan_notifier_block);
 868 }
 869
 870 module_init(macvlan_init_module);
 871 module_exit(macvlan_cleanup_module);
 872
 873 MODULE_LICENSE("GPL");
 874 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 875 MODULE_DESCRIPTION("Driver for MAC address based VLANs");
 876 MODULE_ALIAS_RTNL_LINK("macvlan");