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