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         __u8 ip_summed = skb->ip_summed;
 223
 224         if (vlan->mode == MACVLAN_MODE_BRIDGE) {
 225                 const struct ethhdr *eth = (void *)skb->data;
 226                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 227
 228                 /* send to other bridge ports directly */
 229                 if (is_multicast_ether_addr(eth->h_dest)) {
 230                         macvlan_broadcast(skb, port, dev, MACVLAN_MODE_BRIDGE);
 231                         goto xmit_world;
 232                 }
 233
 234                 dest = macvlan_hash_lookup(port, eth->h_dest);
 235                 if (dest && dest->mode == MACVLAN_MODE_BRIDGE) {
 236                         unsigned int length = skb->len + ETH_HLEN;
 237                         int ret = dest->forward(dest->dev, skb);
 238                         macvlan_count_rx(dest, length,
 239                                          ret == NET_RX_SUCCESS, 0);
 240
 241                         return NET_XMIT_SUCCESS;
 242                 }
 243         }
 244
 245 xmit_world:
 246         skb->ip_summed = ip_summed;
 247         skb_set_dev(skb, vlan->lowerdev);
 248         return dev_queue_xmit(skb);
 249 }
 250
 251 netdev_tx_t macvlan_start_xmit(struct sk_buff *skb,
 252                                struct net_device *dev)
 253 {
 254         unsigned int len = skb->len;
 255         int ret;
 256         const struct macvlan_dev *vlan = netdev_priv(dev);
 257
 258         ret = macvlan_queue_xmit(skb, dev);
 259         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 260                 struct macvlan_pcpu_stats *pcpu_stats;
 261
 262                 pcpu_stats = this_cpu_ptr(vlan->pcpu_stats);
 263                 u64_stats_update_begin(&pcpu_stats->syncp);
 264                 pcpu_stats->tx_packets++;
 265                 pcpu_stats->tx_bytes += len;
 266                 u64_stats_update_end(&pcpu_stats->syncp);
 267         } else {
 268                 this_cpu_inc(vlan->pcpu_stats->tx_dropped);
 269         }
 270         return ret;
 271 }
 272 EXPORT_SYMBOL_GPL(macvlan_start_xmit);
 273
 274 static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
 275                                unsigned short type, const void *daddr,
 276                                const void *saddr, unsigned len)
 277 {
 278         const struct macvlan_dev *vlan = netdev_priv(dev);
 279         struct net_device *lowerdev = vlan->lowerdev;
 280
 281         return dev_hard_header(skb, lowerdev, type, daddr,
 282                                saddr ? : dev->dev_addr, len);
 283 }
 284
 285 static const struct header_ops macvlan_hard_header_ops = {
 286         .create         = macvlan_hard_header,
 287         .rebuild        = eth_rebuild_header,
 288         .parse          = eth_header_parse,
 289         .cache          = eth_header_cache,
 290         .cache_update   = eth_header_cache_update,
 291 };
 292
 293 static int macvlan_open(struct net_device *dev)
 294 {
 295         struct macvlan_dev *vlan = netdev_priv(dev);
 296         struct net_device *lowerdev = vlan->lowerdev;
 297         int err;
 298
 299         if (vlan->port->passthru) {
 300                 dev_set_promiscuity(lowerdev, 1);
 301                 goto hash_add;
 302         }
 303
 304         err = -EBUSY;
 305         if (macvlan_addr_busy(vlan->port, dev->dev_addr))
 306                 goto out;
 307
 308         err = dev_uc_add(lowerdev, dev->dev_addr);
 309         if (err < 0)
 310                 goto out;
 311         if (dev->flags & IFF_ALLMULTI) {
 312                 err = dev_set_allmulti(lowerdev, 1);
 313                 if (err < 0)
 314                         goto del_unicast;
 315         }
 316
 317 hash_add:
 318         macvlan_hash_add(vlan);
 319         return 0;
 320
 321 del_unicast:
 322         dev_uc_del(lowerdev, dev->dev_addr);
 323 out:
 324         return err;
 325 }
 326
 327 static int macvlan_stop(struct net_device *dev)
 328 {
 329         struct macvlan_dev *vlan = netdev_priv(dev);
 330         struct net_device *lowerdev = vlan->lowerdev;
 331
 332         if (vlan->port->passthru) {
 333                 dev_set_promiscuity(lowerdev, -1);
 334                 goto hash_del;
 335         }
 336
 337         dev_mc_unsync(lowerdev, dev);
 338         if (dev->flags & IFF_ALLMULTI)
 339                 dev_set_allmulti(lowerdev, -1);
 340
 341         dev_uc_del(lowerdev, dev->dev_addr);
 342
 343 hash_del:
 344         macvlan_hash_del(vlan);
 345         return 0;
 346 }
 347
 348 static int macvlan_set_mac_address(struct net_device *dev, void *p)
 349 {
 350         struct macvlan_dev *vlan = netdev_priv(dev);
 351         struct net_device *lowerdev = vlan->lowerdev;
 352         struct sockaddr *addr = p;
 353         int err;
 354
 355         if (!is_valid_ether_addr(addr->sa_data))
 356                 return -EADDRNOTAVAIL;
 357
 358         if (!(dev->flags & IFF_UP)) {
 359                 /* Just copy in the new address */
 360                 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 361         } else {
 362                 /* Rehash and update the device filters */
 363                 if (macvlan_addr_busy(vlan->port, addr->sa_data))
 364                         return -EBUSY;
 365
 366                 err = dev_uc_add(lowerdev, addr->sa_data);
 367                 if (err)
 368                         return err;
 369
 370                 dev_uc_del(lowerdev, dev->dev_addr);
 371
 372                 macvlan_hash_change_addr(vlan, addr->sa_data);
 373         }
 374         return 0;
 375 }
 376
 377 static void macvlan_change_rx_flags(struct net_device *dev, int change)
 378 {
 379         struct macvlan_dev *vlan = netdev_priv(dev);
 380         struct net_device *lowerdev = vlan->lowerdev;
 381
 382         if (change & IFF_ALLMULTI)
 383                 dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
 384 }
 385
 386 static void macvlan_set_multicast_list(struct net_device *dev)
 387 {
 388         struct macvlan_dev *vlan = netdev_priv(dev);
 389
 390         dev_mc_sync(vlan->lowerdev, dev);
 391 }
 392
 393 static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
 394 {
 395         struct macvlan_dev *vlan = netdev_priv(dev);
 396
 397         if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
 398                 return -EINVAL;
 399         dev->mtu = new_mtu;
 400         return 0;
 401 }
 402
 403 /*
 404  * macvlan network devices have devices nesting below it and are a special
 405  * "super class" of normal network devices; split their locks off into a
 406  * separate class since they always nest.
 407  */
 408 static struct lock_class_key macvlan_netdev_xmit_lock_key;
 409 static struct lock_class_key macvlan_netdev_addr_lock_key;
 410
 411 #define MACVLAN_FEATURES \
 412         (NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
 413          NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
 414          NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO)
 415
 416 #define MACVLAN_STATE_MASK \
 417         ((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
 418
 419 static void macvlan_set_lockdep_class_one(struct net_device *dev,
 420                                           struct netdev_queue *txq,
 421                                           void *_unused)
 422 {
 423         lockdep_set_class(&txq->_xmit_lock,
 424                           &macvlan_netdev_xmit_lock_key);
 425 }
 426
 427 static void macvlan_set_lockdep_class(struct net_device *dev)
 428 {
 429         lockdep_set_class(&dev->addr_list_lock,
 430                           &macvlan_netdev_addr_lock_key);
 431         netdev_for_each_tx_queue(dev, macvlan_set_lockdep_class_one, NULL);
 432 }
 433
 434 static int macvlan_init(struct net_device *dev)
 435 {
 436         struct macvlan_dev *vlan = netdev_priv(dev);
 437         const struct net_device *lowerdev = vlan->lowerdev;
 438
 439         dev->state              = (dev->state & ~MACVLAN_STATE_MASK) |
 440                                   (lowerdev->state & MACVLAN_STATE_MASK);
 441         dev->features           = lowerdev->features & MACVLAN_FEATURES;
 442         dev->features           |= NETIF_F_LLTX;
 443         dev->gso_max_size       = lowerdev->gso_max_size;
 444         dev->iflink             = lowerdev->ifindex;
 445         dev->hard_header_len    = lowerdev->hard_header_len;
 446
 447         macvlan_set_lockdep_class(dev);
 448
 449         vlan->pcpu_stats = alloc_percpu(struct macvlan_pcpu_stats);
 450         if (!vlan->pcpu_stats)
 451                 return -ENOMEM;
 452
 453         return 0;
 454 }
 455
 456 static void macvlan_uninit(struct net_device *dev)
 457 {
 458         struct macvlan_dev *vlan = netdev_priv(dev);
 459
 460         free_percpu(vlan->pcpu_stats);
 461 }
 462
 463 static struct rtnl_link_stats64 *macvlan_dev_get_stats64(struct net_device *dev,
 464                                                          struct rtnl_link_stats64 *stats)
 465 {
 466         struct macvlan_dev *vlan = netdev_priv(dev);
 467
 468         if (vlan->pcpu_stats) {
 469                 struct macvlan_pcpu_stats *p;
 470                 u64 rx_packets, rx_bytes, rx_multicast, tx_packets, tx_bytes;
 471                 u32 rx_errors = 0, tx_dropped = 0;
 472                 unsigned int start;
 473                 int i;
 474
 475                 for_each_possible_cpu(i) {
 476                         p = per_cpu_ptr(vlan->pcpu_stats, i);
 477                         do {
 478                                 start = u64_stats_fetch_begin_bh(&p->syncp);
 479                                 rx_packets      = p->rx_packets;
 480                                 rx_bytes        = p->rx_bytes;
 481                                 rx_multicast    = p->rx_multicast;
 482                                 tx_packets      = p->tx_packets;
 483                                 tx_bytes        = p->tx_bytes;
 484                         } while (u64_stats_fetch_retry_bh(&p->syncp, start));
 485
 486                         stats->rx_packets       += rx_packets;
 487                         stats->rx_bytes         += rx_bytes;
 488                         stats->multicast        += rx_multicast;
 489                         stats->tx_packets       += tx_packets;
 490                         stats->tx_bytes         += tx_bytes;
 491                         /* rx_errors & tx_dropped are u32, updated
 492                          * without syncp protection.
 493                          */
 494                         rx_errors       += p->rx_errors;
 495                         tx_dropped      += p->tx_dropped;
 496                 }
 497                 stats->rx_errors        = rx_errors;
 498                 stats->rx_dropped       = rx_errors;
 499                 stats->tx_dropped       = tx_dropped;
 500         }
 501         return stats;
 502 }
 503
 504 static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
 505                                         struct ethtool_drvinfo *drvinfo)
 506 {
 507         snprintf(drvinfo->driver, 32, "macvlan");
 508         snprintf(drvinfo->version, 32, "0.1");
 509 }
 510
 511 static u32 macvlan_ethtool_get_rx_csum(struct net_device *dev)
 512 {
 513         const struct macvlan_dev *vlan = netdev_priv(dev);
 514         return dev_ethtool_get_rx_csum(vlan->lowerdev);
 515 }
 516
 517 static int macvlan_ethtool_get_settings(struct net_device *dev,
 518                                         struct ethtool_cmd *cmd)
 519 {
 520         const struct macvlan_dev *vlan = netdev_priv(dev);
 521         return dev_ethtool_get_settings(vlan->lowerdev, cmd);
 522 }
 523
 524 static u32 macvlan_ethtool_get_flags(struct net_device *dev)
 525 {
 526         const struct macvlan_dev *vlan = netdev_priv(dev);
 527         return dev_ethtool_get_flags(vlan->lowerdev);
 528 }
 529
 530 static const struct ethtool_ops macvlan_ethtool_ops = {
 531         .get_link               = ethtool_op_get_link,
 532         .get_settings           = macvlan_ethtool_get_settings,
 533         .get_rx_csum            = macvlan_ethtool_get_rx_csum,
 534         .get_drvinfo            = macvlan_ethtool_get_drvinfo,
 535         .get_flags              = macvlan_ethtool_get_flags,
 536 };
 537
 538 static const struct net_device_ops macvlan_netdev_ops = {
 539         .ndo_init               = macvlan_init,
 540         .ndo_uninit             = macvlan_uninit,
 541         .ndo_open               = macvlan_open,
 542         .ndo_stop               = macvlan_stop,
 543         .ndo_start_xmit         = macvlan_start_xmit,
 544         .ndo_change_mtu         = macvlan_change_mtu,
 545         .ndo_change_rx_flags    = macvlan_change_rx_flags,
 546         .ndo_set_mac_address    = macvlan_set_mac_address,
 547         .ndo_set_multicast_list = macvlan_set_multicast_list,
 548         .ndo_get_stats64        = macvlan_dev_get_stats64,
 549         .ndo_validate_addr      = eth_validate_addr,
 550 };
 551
 552 void macvlan_common_setup(struct net_device *dev)
 553 {
 554         ether_setup(dev);
 555
 556         dev->priv_flags        &= ~IFF_XMIT_DST_RELEASE;
 557         dev->netdev_ops         = &macvlan_netdev_ops;
 558         dev->destructor         = free_netdev;
 559         dev->header_ops         = &macvlan_hard_header_ops,
 560         dev->ethtool_ops        = &macvlan_ethtool_ops;
 561 }
 562 EXPORT_SYMBOL_GPL(macvlan_common_setup);
 563
 564 static void macvlan_setup(struct net_device *dev)
 565 {
 566         macvlan_common_setup(dev);
 567         dev->tx_queue_len       = 0;
 568 }
 569
 570 static int macvlan_port_create(struct net_device *dev)
 571 {
 572         struct macvlan_port *port;
 573         unsigned int i;
 574         int err;
 575
 576         if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
 577                 return -EINVAL;
 578
 579         port = kzalloc(sizeof(*port), GFP_KERNEL);
 580         if (port == NULL)
 581                 return -ENOMEM;
 582
 583         port->passthru = false;
 584         port->dev = dev;
 585         INIT_LIST_HEAD(&port->vlans);
 586         for (i = 0; i < MACVLAN_HASH_SIZE; i++)
 587                 INIT_HLIST_HEAD(&port->vlan_hash[i]);
 588
 589         err = netdev_rx_handler_register(dev, macvlan_handle_frame, port);
 590         if (err)
 591                 kfree(port);
 592
 593         dev->priv_flags |= IFF_MACVLAN_PORT;
 594         return err;
 595 }
 596
 597 static void macvlan_port_rcu_free(struct rcu_head *head)
 598 {
 599         struct macvlan_port *port;
 600
 601         port = container_of(head, struct macvlan_port, rcu);
 602         kfree(port);
 603 }
 604
 605 static void macvlan_port_destroy(struct net_device *dev)
 606 {
 607         struct macvlan_port *port = macvlan_port_get(dev);
 608
 609         dev->priv_flags &= ~IFF_MACVLAN_PORT;
 610         netdev_rx_handler_unregister(dev);
 611         call_rcu(&port->rcu, macvlan_port_rcu_free);
 612 }
 613
 614 static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
 615 {
 616         if (tb[IFLA_ADDRESS]) {
 617                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
 618                         return -EINVAL;
 619                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
 620                         return -EADDRNOTAVAIL;
 621         }
 622
 623         if (data && data[IFLA_MACVLAN_MODE]) {
 624                 switch (nla_get_u32(data[IFLA_MACVLAN_MODE])) {
 625                 case MACVLAN_MODE_PRIVATE:
 626                 case MACVLAN_MODE_VEPA:
 627                 case MACVLAN_MODE_BRIDGE:
 628                 case MACVLAN_MODE_PASSTHRU:
 629                         break;
 630                 default:
 631                         return -EINVAL;
 632                 }
 633         }
 634         return 0;
 635 }
 636
 637 int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
 638                            struct nlattr *tb[], struct nlattr *data[],
 639                            int (*receive)(struct sk_buff *skb),
 640                            int (*forward)(struct net_device *dev,
 641                                           struct sk_buff *skb))
 642 {
 643         struct macvlan_dev *vlan = netdev_priv(dev);
 644         struct macvlan_port *port;
 645         struct net_device *lowerdev;
 646         int err;
 647
 648         if (!tb[IFLA_LINK])
 649                 return -EINVAL;
 650
 651         lowerdev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
 652         if (lowerdev == NULL)
 653                 return -ENODEV;
 654
 655         /* When creating macvlans on top of other macvlans - use
 656          * the real device as the lowerdev.
 657          */
 658         if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops) {
 659                 struct macvlan_dev *lowervlan = netdev_priv(lowerdev);
 660                 lowerdev = lowervlan->lowerdev;
 661         }
 662
 663         if (!tb[IFLA_MTU])
 664                 dev->mtu = lowerdev->mtu;
 665         else if (dev->mtu > lowerdev->mtu)
 666                 return -EINVAL;
 667
 668         if (!tb[IFLA_ADDRESS])
 669                 random_ether_addr(dev->dev_addr);
 670
 671         if (!macvlan_port_exists(lowerdev)) {
 672                 err = macvlan_port_create(lowerdev);
 673                 if (err < 0)
 674                         return err;
 675         }
 676         port = macvlan_port_get(lowerdev);
 677
 678         /* Only 1 macvlan device can be created in passthru mode */
 679         if (port->passthru)
 680                 return -EINVAL;
 681
 682         vlan->lowerdev = lowerdev;
 683         vlan->dev      = dev;
 684         vlan->port     = port;
 685         vlan->receive  = receive;
 686         vlan->forward  = forward;
 687
 688         vlan->mode     = MACVLAN_MODE_VEPA;
 689         if (data && data[IFLA_MACVLAN_MODE])
 690                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
 691
 692         if (vlan->mode == MACVLAN_MODE_PASSTHRU) {
 693                 if (!list_empty(&port->vlans))
 694                         return -EINVAL;
 695                 port->passthru = true;
 696                 memcpy(dev->dev_addr, lowerdev->dev_addr, ETH_ALEN);
 697         }
 698
 699         err = register_netdevice(dev);
 700         if (err < 0)
 701                 goto destroy_port;
 702
 703         list_add_tail(&vlan->list, &port->vlans);
 704         netif_stacked_transfer_operstate(lowerdev, dev);
 705
 706         return 0;
 707
 708 destroy_port:
 709         if (list_empty(&port->vlans))
 710                 macvlan_port_destroy(lowerdev);
 711
 712         return err;
 713 }
 714 EXPORT_SYMBOL_GPL(macvlan_common_newlink);
 715
 716 static int macvlan_newlink(struct net *src_net, struct net_device *dev,
 717                            struct nlattr *tb[], struct nlattr *data[])
 718 {
 719         return macvlan_common_newlink(src_net, dev, tb, data,
 720                                       netif_rx,
 721                                       dev_forward_skb);
 722 }
 723
 724 void macvlan_dellink(struct net_device *dev, struct list_head *head)
 725 {
 726         struct macvlan_dev *vlan = netdev_priv(dev);
 727         struct macvlan_port *port = vlan->port;
 728
 729         list_del(&vlan->list);
 730         unregister_netdevice_queue(dev, head);
 731
 732         if (list_empty(&port->vlans))
 733                 macvlan_port_destroy(port->dev);
 734 }
 735 EXPORT_SYMBOL_GPL(macvlan_dellink);
 736
 737 static int macvlan_changelink(struct net_device *dev,
 738                 struct nlattr *tb[], struct nlattr *data[])
 739 {
 740         struct macvlan_dev *vlan = netdev_priv(dev);
 741         if (data && data[IFLA_MACVLAN_MODE])
 742                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
 743         return 0;
 744 }
 745
 746 static size_t macvlan_get_size(const struct net_device *dev)
 747 {
 748         return nla_total_size(4);
 749 }
 750
 751 static int macvlan_fill_info(struct sk_buff *skb,
 752                                 const struct net_device *dev)
 753 {
 754         struct macvlan_dev *vlan = netdev_priv(dev);
 755
 756         NLA_PUT_U32(skb, IFLA_MACVLAN_MODE, vlan->mode);
 757         return 0;
 758
 759 nla_put_failure:
 760         return -EMSGSIZE;
 761 }
 762
 763 static const struct nla_policy macvlan_policy[IFLA_MACVLAN_MAX + 1] = {
 764         [IFLA_MACVLAN_MODE] = { .type = NLA_U32 },
 765 };
 766
 767 int macvlan_link_register(struct rtnl_link_ops *ops)
 768 {
 769         /* common fields */
 770         ops->priv_size          = sizeof(struct macvlan_dev);
 771         ops->validate           = macvlan_validate;
 772         ops->maxtype            = IFLA_MACVLAN_MAX;
 773         ops->policy             = macvlan_policy;
 774         ops->changelink         = macvlan_changelink;
 775         ops->get_size           = macvlan_get_size;
 776         ops->fill_info          = macvlan_fill_info;
 777
 778         return rtnl_link_register(ops);
 779 };
 780 EXPORT_SYMBOL_GPL(macvlan_link_register);
 781
 782 static struct rtnl_link_ops macvlan_link_ops = {
 783         .kind           = "macvlan",
 784         .setup          = macvlan_setup,
 785         .newlink        = macvlan_newlink,
 786         .dellink        = macvlan_dellink,
 787 };
 788
 789 static int macvlan_device_event(struct notifier_block *unused,
 790                                 unsigned long event, void *ptr)
 791 {
 792         struct net_device *dev = ptr;
 793         struct macvlan_dev *vlan, *next;
 794         struct macvlan_port *port;
 795
 796         if (!macvlan_port_exists(dev))
 797                 return NOTIFY_DONE;
 798
 799         port = macvlan_port_get(dev);
 800
 801         switch (event) {
 802         case NETDEV_CHANGE:
 803                 list_for_each_entry(vlan, &port->vlans, list)
 804                         netif_stacked_transfer_operstate(vlan->lowerdev,
 805                                                          vlan->dev);
 806                 break;
 807         case NETDEV_FEAT_CHANGE:
 808                 list_for_each_entry(vlan, &port->vlans, list) {
 809                         vlan->dev->features = dev->features & MACVLAN_FEATURES;
 810                         vlan->dev->gso_max_size = dev->gso_max_size;
 811                         netdev_features_change(vlan->dev);
 812                 }
 813                 break;
 814         case NETDEV_UNREGISTER:
 815                 /* twiddle thumbs on netns device moves */
 816                 if (dev->reg_state != NETREG_UNREGISTERING)
 817                         break;
 818
 819                 list_for_each_entry_safe(vlan, next, &port->vlans, list)
 820                         vlan->dev->rtnl_link_ops->dellink(vlan->dev, NULL);
 821                 break;
 822         case NETDEV_PRE_TYPE_CHANGE:
 823                 /* Forbid underlaying device to change its type. */
 824                 return NOTIFY_BAD;
 825         }
 826         return NOTIFY_DONE;
 827 }
 828
 829 static struct notifier_block macvlan_notifier_block __read_mostly = {
 830         .notifier_call  = macvlan_device_event,
 831 };
 832
 833 static int __init macvlan_init_module(void)
 834 {
 835         int err;
 836
 837         register_netdevice_notifier(&macvlan_notifier_block);
 838
 839         err = macvlan_link_register(&macvlan_link_ops);
 840         if (err < 0)
 841                 goto err1;
 842         return 0;
 843 err1:
 844         unregister_netdevice_notifier(&macvlan_notifier_block);
 845         return err;
 846 }
 847
 848 static void __exit macvlan_cleanup_module(void)
 849 {
 850         rtnl_link_unregister(&macvlan_link_ops);
 851         unregister_netdevice_notifier(&macvlan_notifier_block);
 852 }
 853
 854 module_init(macvlan_init_module);
 855 module_exit(macvlan_cleanup_module);
 856
 857 MODULE_LICENSE("GPL");
 858 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 859 MODULE_DESCRIPTION("Driver for MAC address based VLANs");
 860 MODULE_ALIAS_RTNL_LINK("macvlan");