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_vlan.h>
  30 #include <linux/if_link.h>
  31 #include <linux/if_macvlan.h>
  32 #include <net/rtnetlink.h>
  33 #include <net/xfrm.h>
  34
  35 #define MACVLAN_HASH_SIZE       (1 << BITS_PER_BYTE)
  36
  37 struct macvlan_port {
  38         struct net_device       *dev;
  39         struct hlist_head       vlan_hash[MACVLAN_HASH_SIZE];
  40         struct list_head        vlans;
  41         struct rcu_head         rcu;
  42         bool                    passthru;
  43         int                     count;
  44 };
  45
  46 static void macvlan_port_destroy(struct net_device *dev);
  47
  48 #define macvlan_port_get_rcu(dev) \
  49         ((struct macvlan_port *) rcu_dereference(dev->rx_handler_data))
  50 #define macvlan_port_get(dev) ((struct macvlan_port *) dev->rx_handler_data)
  51 #define macvlan_port_exists(dev) (dev->priv_flags & IFF_MACVLAN_PORT)
  52
  53 static struct macvlan_dev *macvlan_hash_lookup(const struct macvlan_port *port,
  54                                                const unsigned char *addr)
  55 {
  56         struct macvlan_dev *vlan;
  57         struct hlist_node *n;
  58
  59         hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[addr[5]], hlist) {
  60                 if (!compare_ether_addr_64bits(vlan->dev->dev_addr, addr))
  61                         return vlan;
  62         }
  63         return NULL;
  64 }
  65
  66 static void macvlan_hash_add(struct macvlan_dev *vlan)
  67 {
  68         struct macvlan_port *port = vlan->port;
  69         const unsigned char *addr = vlan->dev->dev_addr;
  70
  71         hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[addr[5]]);
  72 }
  73
  74 static void macvlan_hash_del(struct macvlan_dev *vlan, bool sync)
  75 {
  76         hlist_del_rcu(&vlan->hlist);
  77         if (sync)
  78                 synchronize_rcu();
  79 }
  80
  81 static void macvlan_hash_change_addr(struct macvlan_dev *vlan,
  82                                         const unsigned char *addr)
  83 {
  84         macvlan_hash_del(vlan, true);
  85         /* Now that we are unhashed it is safe to change the device
  86          * address without confusing packet delivery.
  87          */
  88         memcpy(vlan->dev->dev_addr, addr, ETH_ALEN);
  89         macvlan_hash_add(vlan);
  90 }
  91
  92 static int macvlan_addr_busy(const struct macvlan_port *port,
  93                                 const unsigned char *addr)
  94 {
  95         /* Test to see if the specified multicast address is
  96          * currently in use by the underlying device or
  97          * another macvlan.
  98          */
  99         if (!compare_ether_addr_64bits(port->dev->dev_addr, addr))
 100                 return 1;
 101
 102         if (macvlan_hash_lookup(port, addr))
 103                 return 1;
 104
 105         return 0;
 106 }
 107
 108
 109 static int macvlan_broadcast_one(struct sk_buff *skb,
 110                                  const struct macvlan_dev *vlan,
 111                                  const struct ethhdr *eth, bool local)
 112 {
 113         struct net_device *dev = vlan->dev;
 114         if (!skb)
 115                 return NET_RX_DROP;
 116
 117         if (local)
 118                 return vlan->forward(dev, skb);
 119
 120         skb->dev = dev;
 121         if (!compare_ether_addr_64bits(eth->h_dest,
 122                                        dev->broadcast))
 123                 skb->pkt_type = PACKET_BROADCAST;
 124         else
 125                 skb->pkt_type = PACKET_MULTICAST;
 126
 127         return vlan->receive(skb);
 128 }
 129
 130 static void macvlan_broadcast(struct sk_buff *skb,
 131                               const struct macvlan_port *port,
 132                               struct net_device *src,
 133                               enum macvlan_mode mode)
 134 {
 135         const struct ethhdr *eth = eth_hdr(skb);
 136         const struct macvlan_dev *vlan;
 137         struct hlist_node *n;
 138         struct sk_buff *nskb;
 139         unsigned int i;
 140         int err;
 141
 142         if (skb->protocol == htons(ETH_P_PAUSE))
 143                 return;
 144
 145         for (i = 0; i < MACVLAN_HASH_SIZE; i++) {
 146                 hlist_for_each_entry_rcu(vlan, n, &port->vlan_hash[i], hlist) {
 147                         if (vlan->dev == src || !(vlan->mode & mode))
 148                                 continue;
 149
 150                         nskb = skb_clone(skb, GFP_ATOMIC);
 151                         err = macvlan_broadcast_one(nskb, vlan, eth,
 152                                          mode == MACVLAN_MODE_BRIDGE);
 153                         macvlan_count_rx(vlan, skb->len + ETH_HLEN,
 154                                          err == NET_RX_SUCCESS, 1);
 155                 }
 156         }
 157 }
 158
 159 /* called under rcu_read_lock() from netif_receive_skb */
 160 static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb)
 161 {
 162         struct macvlan_port *port;
 163         struct sk_buff *skb = *pskb;
 164         const struct ethhdr *eth = eth_hdr(skb);
 165         const struct macvlan_dev *vlan;
 166         const struct macvlan_dev *src;
 167         struct net_device *dev;
 168         unsigned int len = 0;
 169         int ret = NET_RX_DROP;
 170
 171         port = macvlan_port_get_rcu(skb->dev);
 172         if (is_multicast_ether_addr(eth->h_dest)) {
 173                 skb = ip_check_defrag(skb, IP_DEFRAG_MACVLAN);
 174                 if (!skb)
 175                         return RX_HANDLER_CONSUMED;
 176                 eth = eth_hdr(skb);
 177                 src = macvlan_hash_lookup(port, eth->h_source);
 178                 if (!src)
 179                         /* frame comes from an external address */
 180                         macvlan_broadcast(skb, port, NULL,
 181                                           MACVLAN_MODE_PRIVATE |
 182                                           MACVLAN_MODE_VEPA    |
 183                                           MACVLAN_MODE_PASSTHRU|
 184                                           MACVLAN_MODE_BRIDGE);
 185                 else if (src->mode == MACVLAN_MODE_VEPA)
 186                         /* flood to everyone except source */
 187                         macvlan_broadcast(skb, port, src->dev,
 188                                           MACVLAN_MODE_VEPA |
 189                                           MACVLAN_MODE_BRIDGE);
 190                 else if (src->mode == MACVLAN_MODE_BRIDGE)
 191                         /*
 192                          * flood only to VEPA ports, bridge ports
 193                          * already saw the frame on the way out.
 194                          */
 195                         macvlan_broadcast(skb, port, src->dev,
 196                                           MACVLAN_MODE_VEPA);
 197                 else {
 198                         /* forward to original port. */
 199                         vlan = src;
 200                         ret = macvlan_broadcast_one(skb, vlan, eth, 0);
 201                         goto out;
 202                 }
 203
 204                 return RX_HANDLER_PASS;
 205         }
 206
 207         if (port->passthru)
 208                 vlan = list_first_entry(&port->vlans, struct macvlan_dev, list);
 209         else
 210                 vlan = macvlan_hash_lookup(port, eth->h_dest);
 211         if (vlan == NULL)
 212                 return RX_HANDLER_PASS;
 213
 214         dev = vlan->dev;
 215         if (unlikely(!(dev->flags & IFF_UP))) {
 216                 kfree_skb(skb);
 217                 return RX_HANDLER_CONSUMED;
 218         }
 219         len = skb->len + ETH_HLEN;
 220         skb = skb_share_check(skb, GFP_ATOMIC);
 221         if (!skb)
 222                 goto out;
 223
 224         skb->dev = dev;
 225         skb->pkt_type = PACKET_HOST;
 226
 227         ret = vlan->receive(skb);
 228
 229 out:
 230         macvlan_count_rx(vlan, len, ret == NET_RX_SUCCESS, 0);
 231         return RX_HANDLER_CONSUMED;
 232 }
 233
 234 static int macvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev)
 235 {
 236         const struct macvlan_dev *vlan = netdev_priv(dev);
 237         const struct macvlan_port *port = vlan->port;
 238         const struct macvlan_dev *dest;
 239         __u8 ip_summed = skb->ip_summed;
 240
 241         if (vlan->mode == MACVLAN_MODE_BRIDGE) {
 242                 const struct ethhdr *eth = (void *)skb->data;
 243                 skb->ip_summed = CHECKSUM_UNNECESSARY;
 244
 245                 /* send to other bridge ports directly */
 246                 if (is_multicast_ether_addr(eth->h_dest)) {
 247                         macvlan_broadcast(skb, port, dev, MACVLAN_MODE_BRIDGE);
 248                         goto xmit_world;
 249                 }
 250
 251                 dest = macvlan_hash_lookup(port, eth->h_dest);
 252                 if (dest && dest->mode == MACVLAN_MODE_BRIDGE) {
 253                         /* send to lowerdev first for its network taps */
 254                         dev_forward_skb(vlan->lowerdev, skb);
 255
 256                         return NET_XMIT_SUCCESS;
 257                 }
 258         }
 259
 260 xmit_world:
 261         skb->ip_summed = ip_summed;
 262         skb_set_dev(skb, vlan->lowerdev);
 263         return dev_queue_xmit(skb);
 264 }
 265
 266 netdev_tx_t macvlan_start_xmit(struct sk_buff *skb,
 267                                struct net_device *dev)
 268 {
 269         unsigned int len = skb->len;
 270         int ret;
 271         const struct macvlan_dev *vlan = netdev_priv(dev);
 272
 273         ret = macvlan_queue_xmit(skb, dev);
 274         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 275                 struct macvlan_pcpu_stats *pcpu_stats;
 276
 277                 pcpu_stats = this_cpu_ptr(vlan->pcpu_stats);
 278                 u64_stats_update_begin(&pcpu_stats->syncp);
 279                 pcpu_stats->tx_packets++;
 280                 pcpu_stats->tx_bytes += len;
 281                 u64_stats_update_end(&pcpu_stats->syncp);
 282         } else {
 283                 this_cpu_inc(vlan->pcpu_stats->tx_dropped);
 284         }
 285         return ret;
 286 }
 287 EXPORT_SYMBOL_GPL(macvlan_start_xmit);
 288
 289 static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
 290                                unsigned short type, const void *daddr,
 291                                const void *saddr, unsigned len)
 292 {
 293         const struct macvlan_dev *vlan = netdev_priv(dev);
 294         struct net_device *lowerdev = vlan->lowerdev;
 295
 296         return dev_hard_header(skb, lowerdev, type, daddr,
 297                                saddr ? : dev->dev_addr, len);
 298 }
 299
 300 static const struct header_ops macvlan_hard_header_ops = {
 301         .create         = macvlan_hard_header,
 302         .rebuild        = eth_rebuild_header,
 303         .parse          = eth_header_parse,
 304         .cache          = eth_header_cache,
 305         .cache_update   = eth_header_cache_update,
 306 };
 307
 308 static int macvlan_open(struct net_device *dev)
 309 {
 310         struct macvlan_dev *vlan = netdev_priv(dev);
 311         struct net_device *lowerdev = vlan->lowerdev;
 312         int err;
 313
 314         if (vlan->port->passthru) {
 315                 dev_set_promiscuity(lowerdev, 1);
 316                 goto hash_add;
 317         }
 318
 319         err = -EBUSY;
 320         if (macvlan_addr_busy(vlan->port, dev->dev_addr))
 321                 goto out;
 322
 323         err = dev_uc_add(lowerdev, dev->dev_addr);
 324         if (err < 0)
 325                 goto out;
 326         if (dev->flags & IFF_ALLMULTI) {
 327                 err = dev_set_allmulti(lowerdev, 1);
 328                 if (err < 0)
 329                         goto del_unicast;
 330         }
 331
 332 hash_add:
 333         macvlan_hash_add(vlan);
 334         return 0;
 335
 336 del_unicast:
 337         dev_uc_del(lowerdev, dev->dev_addr);
 338 out:
 339         return err;
 340 }
 341
 342 static int macvlan_stop(struct net_device *dev)
 343 {
 344         struct macvlan_dev *vlan = netdev_priv(dev);
 345         struct net_device *lowerdev = vlan->lowerdev;
 346
 347         if (vlan->port->passthru) {
 348                 dev_set_promiscuity(lowerdev, -1);
 349                 goto hash_del;
 350         }
 351
 352         dev_mc_unsync(lowerdev, dev);
 353         if (dev->flags & IFF_ALLMULTI)
 354                 dev_set_allmulti(lowerdev, -1);
 355
 356         dev_uc_del(lowerdev, dev->dev_addr);
 357
 358 hash_del:
 359         macvlan_hash_del(vlan, !dev->dismantle);
 360         return 0;
 361 }
 362
 363 static int macvlan_set_mac_address(struct net_device *dev, void *p)
 364 {
 365         struct macvlan_dev *vlan = netdev_priv(dev);
 366         struct net_device *lowerdev = vlan->lowerdev;
 367         struct sockaddr *addr = p;
 368         int err;
 369
 370         if (!is_valid_ether_addr(addr->sa_data))
 371                 return -EADDRNOTAVAIL;
 372
 373         if (!(dev->flags & IFF_UP)) {
 374                 /* Just copy in the new address */
 375                 memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
 376         } else {
 377                 /* Rehash and update the device filters */
 378                 if (macvlan_addr_busy(vlan->port, addr->sa_data))
 379                         return -EBUSY;
 380
 381                 err = dev_uc_add(lowerdev, addr->sa_data);
 382                 if (err)
 383                         return err;
 384
 385                 dev_uc_del(lowerdev, dev->dev_addr);
 386
 387                 macvlan_hash_change_addr(vlan, addr->sa_data);
 388         }
 389         return 0;
 390 }
 391
 392 static void macvlan_change_rx_flags(struct net_device *dev, int change)
 393 {
 394         struct macvlan_dev *vlan = netdev_priv(dev);
 395         struct net_device *lowerdev = vlan->lowerdev;
 396
 397         if (change & IFF_ALLMULTI)
 398                 dev_set_allmulti(lowerdev, dev->flags & IFF_ALLMULTI ? 1 : -1);
 399 }
 400
 401 static void macvlan_set_multicast_list(struct net_device *dev)
 402 {
 403         struct macvlan_dev *vlan = netdev_priv(dev);
 404
 405         dev_mc_sync(vlan->lowerdev, dev);
 406 }
 407
 408 static int macvlan_change_mtu(struct net_device *dev, int new_mtu)
 409 {
 410         struct macvlan_dev *vlan = netdev_priv(dev);
 411
 412         if (new_mtu < 68 || vlan->lowerdev->mtu < new_mtu)
 413                 return -EINVAL;
 414         dev->mtu = new_mtu;
 415         return 0;
 416 }
 417
 418 /*
 419  * macvlan network devices have devices nesting below it and are a special
 420  * "super class" of normal network devices; split their locks off into a
 421  * separate class since they always nest.
 422  */
 423 static struct lock_class_key macvlan_netdev_xmit_lock_key;
 424 static struct lock_class_key macvlan_netdev_addr_lock_key;
 425
 426 #define MACVLAN_FEATURES \
 427         (NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
 428          NETIF_F_GSO | NETIF_F_TSO | NETIF_F_UFO | NETIF_F_GSO_ROBUST | \
 429          NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM | \
 430          NETIF_F_HW_VLAN_FILTER)
 431
 432 #define MACVLAN_STATE_MASK \
 433         ((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
 434
 435 static void macvlan_set_lockdep_class_one(struct net_device *dev,
 436                                           struct netdev_queue *txq,
 437                                           void *_unused)
 438 {
 439         lockdep_set_class(&txq->_xmit_lock,
 440                           &macvlan_netdev_xmit_lock_key);
 441 }
 442
 443 static void macvlan_set_lockdep_class(struct net_device *dev)
 444 {
 445         lockdep_set_class(&dev->addr_list_lock,
 446                           &macvlan_netdev_addr_lock_key);
 447         netdev_for_each_tx_queue(dev, macvlan_set_lockdep_class_one, NULL);
 448 }
 449
 450 static int macvlan_init(struct net_device *dev)
 451 {
 452         struct macvlan_dev *vlan = netdev_priv(dev);
 453         const struct net_device *lowerdev = vlan->lowerdev;
 454
 455         dev->state              = (dev->state & ~MACVLAN_STATE_MASK) |
 456                                   (lowerdev->state & MACVLAN_STATE_MASK);
 457         dev->features           = lowerdev->features & MACVLAN_FEATURES;
 458         dev->features           |= NETIF_F_LLTX;
 459         dev->gso_max_size       = lowerdev->gso_max_size;
 460         dev->iflink             = lowerdev->ifindex;
 461         dev->hard_header_len    = lowerdev->hard_header_len;
 462
 463         macvlan_set_lockdep_class(dev);
 464
 465         vlan->pcpu_stats = alloc_percpu(struct macvlan_pcpu_stats);
 466         if (!vlan->pcpu_stats)
 467                 return -ENOMEM;
 468
 469         return 0;
 470 }
 471
 472 static void macvlan_uninit(struct net_device *dev)
 473 {
 474         struct macvlan_dev *vlan = netdev_priv(dev);
 475         struct macvlan_port *port = vlan->port;
 476
 477         free_percpu(vlan->pcpu_stats);
 478
 479         port->count -= 1;
 480         if (!port->count)
 481                 macvlan_port_destroy(port->dev);
 482 }
 483
 484 static struct rtnl_link_stats64 *macvlan_dev_get_stats64(struct net_device *dev,
 485                                                          struct rtnl_link_stats64 *stats)
 486 {
 487         struct macvlan_dev *vlan = netdev_priv(dev);
 488
 489         if (vlan->pcpu_stats) {
 490                 struct macvlan_pcpu_stats *p;
 491                 u64 rx_packets, rx_bytes, rx_multicast, tx_packets, tx_bytes;
 492                 u32 rx_errors = 0, tx_dropped = 0;
 493                 unsigned int start;
 494                 int i;
 495
 496                 for_each_possible_cpu(i) {
 497                         p = per_cpu_ptr(vlan->pcpu_stats, i);
 498                         do {
 499                                 start = u64_stats_fetch_begin_bh(&p->syncp);
 500                                 rx_packets      = p->rx_packets;
 501                                 rx_bytes        = p->rx_bytes;
 502                                 rx_multicast    = p->rx_multicast;
 503                                 tx_packets      = p->tx_packets;
 504                                 tx_bytes        = p->tx_bytes;
 505                         } while (u64_stats_fetch_retry_bh(&p->syncp, start));
 506
 507                         stats->rx_packets       += rx_packets;
 508                         stats->rx_bytes         += rx_bytes;
 509                         stats->multicast        += rx_multicast;
 510                         stats->tx_packets       += tx_packets;
 511                         stats->tx_bytes         += tx_bytes;
 512                         /* rx_errors & tx_dropped are u32, updated
 513                          * without syncp protection.
 514                          */
 515                         rx_errors       += p->rx_errors;
 516                         tx_dropped      += p->tx_dropped;
 517                 }
 518                 stats->rx_errors        = rx_errors;
 519                 stats->rx_dropped       = rx_errors;
 520                 stats->tx_dropped       = tx_dropped;
 521         }
 522         return stats;
 523 }
 524
 525 static int macvlan_vlan_rx_add_vid(struct net_device *dev,
 526                                     unsigned short vid)
 527 {
 528         struct macvlan_dev *vlan = netdev_priv(dev);
 529         struct net_device *lowerdev = vlan->lowerdev;
 530
 531         return vlan_vid_add(lowerdev, vid);
 532 }
 533
 534 static int macvlan_vlan_rx_kill_vid(struct net_device *dev,
 535                                      unsigned short vid)
 536 {
 537         struct macvlan_dev *vlan = netdev_priv(dev);
 538         struct net_device *lowerdev = vlan->lowerdev;
 539
 540         vlan_vid_del(lowerdev, vid);
 541         return 0;
 542 }
 543
 544 static void macvlan_ethtool_get_drvinfo(struct net_device *dev,
 545                                         struct ethtool_drvinfo *drvinfo)
 546 {
 547         snprintf(drvinfo->driver, 32, "macvlan");
 548         snprintf(drvinfo->version, 32, "0.1");
 549 }
 550
 551 static int macvlan_ethtool_get_settings(struct net_device *dev,
 552                                         struct ethtool_cmd *cmd)
 553 {
 554         const struct macvlan_dev *vlan = netdev_priv(dev);
 555
 556         return __ethtool_get_settings(vlan->lowerdev, cmd);
 557 }
 558
 559 static const struct ethtool_ops macvlan_ethtool_ops = {
 560         .get_link               = ethtool_op_get_link,
 561         .get_settings           = macvlan_ethtool_get_settings,
 562         .get_drvinfo            = macvlan_ethtool_get_drvinfo,
 563 };
 564
 565 static const struct net_device_ops macvlan_netdev_ops = {
 566         .ndo_init               = macvlan_init,
 567         .ndo_uninit             = macvlan_uninit,
 568         .ndo_open               = macvlan_open,
 569         .ndo_stop               = macvlan_stop,
 570         .ndo_start_xmit         = macvlan_start_xmit,
 571         .ndo_change_mtu         = macvlan_change_mtu,
 572         .ndo_change_rx_flags    = macvlan_change_rx_flags,
 573         .ndo_set_mac_address    = macvlan_set_mac_address,
 574         .ndo_set_rx_mode        = macvlan_set_multicast_list,
 575         .ndo_get_stats64        = macvlan_dev_get_stats64,
 576         .ndo_validate_addr      = eth_validate_addr,
 577         .ndo_vlan_rx_add_vid    = macvlan_vlan_rx_add_vid,
 578         .ndo_vlan_rx_kill_vid   = macvlan_vlan_rx_kill_vid,
 579 };
 580
 581 void macvlan_common_setup(struct net_device *dev)
 582 {
 583         ether_setup(dev);
 584
 585         dev->priv_flags        &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
 586         dev->netdev_ops         = &macvlan_netdev_ops;
 587         dev->destructor         = free_netdev;
 588         dev->header_ops         = &macvlan_hard_header_ops,
 589         dev->ethtool_ops        = &macvlan_ethtool_ops;
 590 }
 591 EXPORT_SYMBOL_GPL(macvlan_common_setup);
 592
 593 static void macvlan_setup(struct net_device *dev)
 594 {
 595         macvlan_common_setup(dev);
 596         dev->tx_queue_len       = 0;
 597 }
 598
 599 static int macvlan_port_create(struct net_device *dev)
 600 {
 601         struct macvlan_port *port;
 602         unsigned int i;
 603         int err;
 604
 605         if (dev->type != ARPHRD_ETHER || dev->flags & IFF_LOOPBACK)
 606                 return -EINVAL;
 607
 608         port = kzalloc(sizeof(*port), GFP_KERNEL);
 609         if (port == NULL)
 610                 return -ENOMEM;
 611
 612         port->passthru = false;
 613         port->dev = dev;
 614         INIT_LIST_HEAD(&port->vlans);
 615         for (i = 0; i < MACVLAN_HASH_SIZE; i++)
 616                 INIT_HLIST_HEAD(&port->vlan_hash[i]);
 617
 618         err = netdev_rx_handler_register(dev, macvlan_handle_frame, port);
 619         if (err)
 620                 kfree(port);
 621         else
 622                 dev->priv_flags |= IFF_MACVLAN_PORT;
 623         return err;
 624 }
 625
 626 static void macvlan_port_destroy(struct net_device *dev)
 627 {
 628         struct macvlan_port *port = macvlan_port_get(dev);
 629
 630         dev->priv_flags &= ~IFF_MACVLAN_PORT;
 631         netdev_rx_handler_unregister(dev);
 632         kfree_rcu(port, rcu);
 633 }
 634
 635 static int macvlan_validate(struct nlattr *tb[], struct nlattr *data[])
 636 {
 637         if (tb[IFLA_ADDRESS]) {
 638                 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN)
 639                         return -EINVAL;
 640                 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS])))
 641                         return -EADDRNOTAVAIL;
 642         }
 643
 644         if (data && data[IFLA_MACVLAN_MODE]) {
 645                 switch (nla_get_u32(data[IFLA_MACVLAN_MODE])) {
 646                 case MACVLAN_MODE_PRIVATE:
 647                 case MACVLAN_MODE_VEPA:
 648                 case MACVLAN_MODE_BRIDGE:
 649                 case MACVLAN_MODE_PASSTHRU:
 650                         break;
 651                 default:
 652                         return -EINVAL;
 653                 }
 654         }
 655         return 0;
 656 }
 657
 658 int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
 659                            struct nlattr *tb[], struct nlattr *data[],
 660                            int (*receive)(struct sk_buff *skb),
 661                            int (*forward)(struct net_device *dev,
 662                                           struct sk_buff *skb))
 663 {
 664         struct macvlan_dev *vlan = netdev_priv(dev);
 665         struct macvlan_port *port;
 666         struct net_device *lowerdev;
 667         int err;
 668
 669         if (!tb[IFLA_LINK])
 670                 return -EINVAL;
 671
 672         lowerdev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
 673         if (lowerdev == NULL)
 674                 return -ENODEV;
 675
 676         /* When creating macvlans on top of other macvlans - use
 677          * the real device as the lowerdev.
 678          */
 679         if (lowerdev->rtnl_link_ops == dev->rtnl_link_ops) {
 680                 struct macvlan_dev *lowervlan = netdev_priv(lowerdev);
 681                 lowerdev = lowervlan->lowerdev;
 682         }
 683
 684         if (!tb[IFLA_MTU])
 685                 dev->mtu = lowerdev->mtu;
 686         else if (dev->mtu > lowerdev->mtu)
 687                 return -EINVAL;
 688
 689         if (!tb[IFLA_ADDRESS])
 690                 random_ether_addr(dev->dev_addr);
 691
 692         if (!macvlan_port_exists(lowerdev)) {
 693                 err = macvlan_port_create(lowerdev);
 694                 if (err < 0)
 695                         return err;
 696         }
 697         port = macvlan_port_get(lowerdev);
 698
 699         /* Only 1 macvlan device can be created in passthru mode */
 700         if (port->passthru)
 701                 return -EINVAL;
 702
 703         vlan->lowerdev = lowerdev;
 704         vlan->dev      = dev;
 705         vlan->port     = port;
 706         vlan->receive  = receive;
 707         vlan->forward  = forward;
 708
 709         vlan->mode     = MACVLAN_MODE_VEPA;
 710         if (data && data[IFLA_MACVLAN_MODE])
 711                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
 712
 713         if (vlan->mode == MACVLAN_MODE_PASSTHRU) {
 714                 if (port->count)
 715                         return -EINVAL;
 716                 port->passthru = true;
 717                 memcpy(dev->dev_addr, lowerdev->dev_addr, ETH_ALEN);
 718         }
 719
 720         port->count += 1;
 721         err = register_netdevice(dev);
 722         if (err < 0)
 723                 goto destroy_port;
 724
 725         list_add_tail(&vlan->list, &port->vlans);
 726         netif_stacked_transfer_operstate(lowerdev, dev);
 727
 728         return 0;
 729
 730 destroy_port:
 731         port->count -= 1;
 732         if (!port->count)
 733                 macvlan_port_destroy(lowerdev);
 734
 735         return err;
 736 }
 737 EXPORT_SYMBOL_GPL(macvlan_common_newlink);
 738
 739 static int macvlan_newlink(struct net *src_net, struct net_device *dev,
 740                            struct nlattr *tb[], struct nlattr *data[])
 741 {
 742         return macvlan_common_newlink(src_net, dev, tb, data,
 743                                       netif_rx,
 744                                       dev_forward_skb);
 745 }
 746
 747 void macvlan_dellink(struct net_device *dev, struct list_head *head)
 748 {
 749         struct macvlan_dev *vlan = netdev_priv(dev);
 750
 751         list_del(&vlan->list);
 752         unregister_netdevice_queue(dev, head);
 753 }
 754 EXPORT_SYMBOL_GPL(macvlan_dellink);
 755
 756 static int macvlan_changelink(struct net_device *dev,
 757                 struct nlattr *tb[], struct nlattr *data[])
 758 {
 759         struct macvlan_dev *vlan = netdev_priv(dev);
 760         if (data && data[IFLA_MACVLAN_MODE])
 761                 vlan->mode = nla_get_u32(data[IFLA_MACVLAN_MODE]);
 762         return 0;
 763 }
 764
 765 static size_t macvlan_get_size(const struct net_device *dev)
 766 {
 767         return nla_total_size(4);
 768 }
 769
 770 static int macvlan_fill_info(struct sk_buff *skb,
 771                                 const struct net_device *dev)
 772 {
 773         struct macvlan_dev *vlan = netdev_priv(dev);
 774
 775         NLA_PUT_U32(skb, IFLA_MACVLAN_MODE, vlan->mode);
 776         return 0;
 777
 778 nla_put_failure:
 779         return -EMSGSIZE;
 780 }
 781
 782 static const struct nla_policy macvlan_policy[IFLA_MACVLAN_MAX + 1] = {
 783         [IFLA_MACVLAN_MODE] = { .type = NLA_U32 },
 784 };
 785
 786 int macvlan_link_register(struct rtnl_link_ops *ops)
 787 {
 788         /* common fields */
 789         ops->priv_size          = sizeof(struct macvlan_dev);
 790         ops->validate           = macvlan_validate;
 791         ops->maxtype            = IFLA_MACVLAN_MAX;
 792         ops->policy             = macvlan_policy;
 793         ops->changelink         = macvlan_changelink;
 794         ops->get_size           = macvlan_get_size;
 795         ops->fill_info          = macvlan_fill_info;
 796
 797         return rtnl_link_register(ops);
 798 };
 799 EXPORT_SYMBOL_GPL(macvlan_link_register);
 800
 801 static struct rtnl_link_ops macvlan_link_ops = {
 802         .kind           = "macvlan",
 803         .setup          = macvlan_setup,
 804         .newlink        = macvlan_newlink,
 805         .dellink        = macvlan_dellink,
 806 };
 807
 808 static int macvlan_device_event(struct notifier_block *unused,
 809                                 unsigned long event, void *ptr)
 810 {
 811         struct net_device *dev = ptr;
 812         struct macvlan_dev *vlan, *next;
 813         struct macvlan_port *port;
 814         LIST_HEAD(list_kill);
 815
 816         if (!macvlan_port_exists(dev))
 817                 return NOTIFY_DONE;
 818
 819         port = macvlan_port_get(dev);
 820
 821         switch (event) {
 822         case NETDEV_CHANGE:
 823                 list_for_each_entry(vlan, &port->vlans, list)
 824                         netif_stacked_transfer_operstate(vlan->lowerdev,
 825                                                          vlan->dev);
 826                 break;
 827         case NETDEV_FEAT_CHANGE:
 828                 list_for_each_entry(vlan, &port->vlans, list) {
 829                         vlan->dev->features = dev->features & MACVLAN_FEATURES;
 830                         vlan->dev->gso_max_size = dev->gso_max_size;
 831                         netdev_features_change(vlan->dev);
 832                 }
 833                 break;
 834         case NETDEV_UNREGISTER:
 835                 /* twiddle thumbs on netns device moves */
 836                 if (dev->reg_state != NETREG_UNREGISTERING)
 837                         break;
 838
 839                 list_for_each_entry_safe(vlan, next, &port->vlans, list)
 840                         vlan->dev->rtnl_link_ops->dellink(vlan->dev, &list_kill);
 841                 unregister_netdevice_many(&list_kill);
 842                 list_del(&list_kill);
 843                 break;
 844         case NETDEV_PRE_TYPE_CHANGE:
 845                 /* Forbid underlaying device to change its type. */
 846                 return NOTIFY_BAD;
 847         }
 848         return NOTIFY_DONE;
 849 }
 850
 851 static struct notifier_block macvlan_notifier_block __read_mostly = {
 852         .notifier_call  = macvlan_device_event,
 853 };
 854
 855 static int __init macvlan_init_module(void)
 856 {
 857         int err;
 858
 859         register_netdevice_notifier(&macvlan_notifier_block);
 860
 861         err = macvlan_link_register(&macvlan_link_ops);
 862         if (err < 0)
 863                 goto err1;
 864         return 0;
 865 err1:
 866         unregister_netdevice_notifier(&macvlan_notifier_block);
 867         return err;
 868 }
 869
 870 static void __exit macvlan_cleanup_module(void)
 871 {
 872         rtnl_link_unregister(&macvlan_link_ops);
 873         unregister_netdevice_notifier(&macvlan_notifier_block);
 874 }
 875
 876 module_init(macvlan_init_module);
 877 module_exit(macvlan_cleanup_module);
 878
 879 MODULE_LICENSE("GPL");
 880 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 881 MODULE_DESCRIPTION("Driver for MAC address based VLANs");
 882 MODULE_ALIAS_RTNL_LINK("macvlan");