drivers/net/macvlan.c

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