drivers/net/ipvlan/ipvlan_main.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* Copyright (c) 2014 Mahesh Bandewar <maheshb@google.com>
   3  */
   4
   5 #include "ipvlan.h"
   6
   7 static int ipvlan_set_port_mode(struct ipvl_port *port, u16 nval,
   8                                 struct netlink_ext_ack *extack)
   9 {
  10         struct ipvl_dev *ipvlan;
  11         unsigned int flags;
  12         int err;
  13
  14         ASSERT_RTNL();
  15         if (port->mode != nval) {
  16                 list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
  17                         flags = ipvlan->dev->flags;
  18                         if (nval == IPVLAN_MODE_L3 || nval == IPVLAN_MODE_L3S) {
  19                                 err = dev_change_flags(ipvlan->dev,
  20                                                        flags | IFF_NOARP,
  21                                                        extack);
  22                         } else {
  23                                 err = dev_change_flags(ipvlan->dev,
  24                                                        flags & ~IFF_NOARP,
  25                                                        extack);
  26                         }
  27                         if (unlikely(err))
  28                                 goto fail;
  29                 }
  30                 if (nval == IPVLAN_MODE_L3S) {
  31                         /* New mode is L3S */
  32                         err = ipvlan_l3s_register(port);
  33                         if (err)
  34                                 goto fail;
  35                 } else if (port->mode == IPVLAN_MODE_L3S) {
  36                         /* Old mode was L3S */
  37                         ipvlan_l3s_unregister(port);
  38                 }
  39                 port->mode = nval;
  40         }
  41         return 0;
  42
  43 fail:
  44         /* Undo the flags changes that have been done so far. */
  45         list_for_each_entry_continue_reverse(ipvlan, &port->ipvlans, pnode) {
  46                 flags = ipvlan->dev->flags;
  47                 if (port->mode == IPVLAN_MODE_L3 ||
  48                     port->mode == IPVLAN_MODE_L3S)
  49                         dev_change_flags(ipvlan->dev, flags | IFF_NOARP,
  50                                          NULL);
  51                 else
  52                         dev_change_flags(ipvlan->dev, flags & ~IFF_NOARP,
  53                                          NULL);
  54         }
  55
  56         return err;
  57 }
  58
  59 static int ipvlan_port_create(struct net_device *dev)
  60 {
  61         struct ipvl_port *port;
  62         int err, idx;
  63
  64         port = kzalloc(sizeof(struct ipvl_port), GFP_KERNEL);
  65         if (!port)
  66                 return -ENOMEM;
  67
  68         write_pnet(&port->pnet, dev_net(dev));
  69         port->dev = dev;
  70         port->mode = IPVLAN_MODE_L3;
  71         INIT_LIST_HEAD(&port->ipvlans);
  72         for (idx = 0; idx < IPVLAN_HASH_SIZE; idx++)
  73                 INIT_HLIST_HEAD(&port->hlhead[idx]);
  74
  75         skb_queue_head_init(&port->backlog);
  76         INIT_WORK(&port->wq, ipvlan_process_multicast);
  77         ida_init(&port->ida);
  78         port->dev_id_start = 1;
  79
  80         err = netdev_rx_handler_register(dev, ipvlan_handle_frame, port);
  81         if (err)
  82                 goto err;
  83
  84         return 0;
  85
  86 err:
  87         kfree(port);
  88         return err;
  89 }
  90
  91 static void ipvlan_port_destroy(struct net_device *dev)
  92 {
  93         struct ipvl_port *port = ipvlan_port_get_rtnl(dev);
  94         struct sk_buff *skb;
  95
  96         if (port->mode == IPVLAN_MODE_L3S)
  97                 ipvlan_l3s_unregister(port);
  98         netdev_rx_handler_unregister(dev);
  99         cancel_work_sync(&port->wq);
 100         while ((skb = __skb_dequeue(&port->backlog)) != NULL) {
 101                 if (skb->dev)
 102                         dev_put(skb->dev);
 103                 kfree_skb(skb);
 104         }
 105         ida_destroy(&port->ida);
 106         kfree(port);
 107 }
 108
 109 #define IPVLAN_FEATURES \
 110         (NETIF_F_SG | NETIF_F_CSUM_MASK | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
 111          NETIF_F_GSO | NETIF_F_TSO | NETIF_F_GSO_ROBUST | \
 112          NETIF_F_TSO_ECN | NETIF_F_TSO6 | NETIF_F_GRO | NETIF_F_RXCSUM | \
 113          NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_HW_VLAN_STAG_FILTER)
 114
 115 #define IPVLAN_STATE_MASK \
 116         ((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
 117
 118 static int ipvlan_init(struct net_device *dev)
 119 {
 120         struct ipvl_dev *ipvlan = netdev_priv(dev);
 121         struct net_device *phy_dev = ipvlan->phy_dev;
 122         struct ipvl_port *port;
 123         int err;
 124
 125         dev->state = (dev->state & ~IPVLAN_STATE_MASK) |
 126                      (phy_dev->state & IPVLAN_STATE_MASK);
 127         dev->features = phy_dev->features & IPVLAN_FEATURES;
 128         dev->features |= NETIF_F_LLTX | NETIF_F_VLAN_CHALLENGED;
 129         dev->hw_enc_features |= dev->features;
 130         dev->gso_max_size = phy_dev->gso_max_size;
 131         dev->gso_max_segs = phy_dev->gso_max_segs;
 132         dev->hard_header_len = phy_dev->hard_header_len;
 133
 134         netdev_lockdep_set_classes(dev);
 135
 136         ipvlan->pcpu_stats = netdev_alloc_pcpu_stats(struct ipvl_pcpu_stats);
 137         if (!ipvlan->pcpu_stats)
 138                 return -ENOMEM;
 139
 140         if (!netif_is_ipvlan_port(phy_dev)) {
 141                 err = ipvlan_port_create(phy_dev);
 142                 if (err < 0) {
 143                         free_percpu(ipvlan->pcpu_stats);
 144                         return err;
 145                 }
 146         }
 147         port = ipvlan_port_get_rtnl(phy_dev);
 148         port->count += 1;
 149         return 0;
 150 }
 151
 152 static void ipvlan_uninit(struct net_device *dev)
 153 {
 154         struct ipvl_dev *ipvlan = netdev_priv(dev);
 155         struct net_device *phy_dev = ipvlan->phy_dev;
 156         struct ipvl_port *port;
 157
 158         free_percpu(ipvlan->pcpu_stats);
 159
 160         port = ipvlan_port_get_rtnl(phy_dev);
 161         port->count -= 1;
 162         if (!port->count)
 163                 ipvlan_port_destroy(port->dev);
 164 }
 165
 166 static int ipvlan_open(struct net_device *dev)
 167 {
 168         struct ipvl_dev *ipvlan = netdev_priv(dev);
 169         struct net_device *phy_dev = ipvlan->phy_dev;
 170         struct ipvl_addr *addr;
 171
 172         if (ipvlan->port->mode == IPVLAN_MODE_L3 ||
 173             ipvlan->port->mode == IPVLAN_MODE_L3S)
 174                 dev->flags |= IFF_NOARP;
 175         else
 176                 dev->flags &= ~IFF_NOARP;
 177
 178         rcu_read_lock();
 179         list_for_each_entry_rcu(addr, &ipvlan->addrs, anode)
 180                 ipvlan_ht_addr_add(ipvlan, addr);
 181         rcu_read_unlock();
 182
 183         return dev_uc_add(phy_dev, phy_dev->dev_addr);
 184 }
 185
 186 static int ipvlan_stop(struct net_device *dev)
 187 {
 188         struct ipvl_dev *ipvlan = netdev_priv(dev);
 189         struct net_device *phy_dev = ipvlan->phy_dev;
 190         struct ipvl_addr *addr;
 191
 192         dev_uc_unsync(phy_dev, dev);
 193         dev_mc_unsync(phy_dev, dev);
 194
 195         dev_uc_del(phy_dev, phy_dev->dev_addr);
 196
 197         rcu_read_lock();
 198         list_for_each_entry_rcu(addr, &ipvlan->addrs, anode)
 199                 ipvlan_ht_addr_del(addr);
 200         rcu_read_unlock();
 201
 202         return 0;
 203 }
 204
 205 static netdev_tx_t ipvlan_start_xmit(struct sk_buff *skb,
 206                                      struct net_device *dev)
 207 {
 208         const struct ipvl_dev *ipvlan = netdev_priv(dev);
 209         int skblen = skb->len;
 210         int ret;
 211
 212         ret = ipvlan_queue_xmit(skb, dev);
 213         if (likely(ret == NET_XMIT_SUCCESS || ret == NET_XMIT_CN)) {
 214                 struct ipvl_pcpu_stats *pcptr;
 215
 216                 pcptr = this_cpu_ptr(ipvlan->pcpu_stats);
 217
 218                 u64_stats_update_begin(&pcptr->syncp);
 219                 pcptr->tx_pkts++;
 220                 pcptr->tx_bytes += skblen;
 221                 u64_stats_update_end(&pcptr->syncp);
 222         } else {
 223                 this_cpu_inc(ipvlan->pcpu_stats->tx_drps);
 224         }
 225         return ret;
 226 }
 227
 228 static netdev_features_t ipvlan_fix_features(struct net_device *dev,
 229                                              netdev_features_t features)
 230 {
 231         struct ipvl_dev *ipvlan = netdev_priv(dev);
 232
 233         return features & (ipvlan->sfeatures | ~IPVLAN_FEATURES);
 234 }
 235
 236 static void ipvlan_change_rx_flags(struct net_device *dev, int change)
 237 {
 238         struct ipvl_dev *ipvlan = netdev_priv(dev);
 239         struct net_device *phy_dev = ipvlan->phy_dev;
 240
 241         if (change & IFF_ALLMULTI)
 242                 dev_set_allmulti(phy_dev, dev->flags & IFF_ALLMULTI? 1 : -1);
 243 }
 244
 245 static void ipvlan_set_multicast_mac_filter(struct net_device *dev)
 246 {
 247         struct ipvl_dev *ipvlan = netdev_priv(dev);
 248
 249         if (dev->flags & (IFF_PROMISC | IFF_ALLMULTI)) {
 250                 bitmap_fill(ipvlan->mac_filters, IPVLAN_MAC_FILTER_SIZE);
 251         } else {
 252                 struct netdev_hw_addr *ha;
 253                 DECLARE_BITMAP(mc_filters, IPVLAN_MAC_FILTER_SIZE);
 254
 255                 bitmap_zero(mc_filters, IPVLAN_MAC_FILTER_SIZE);
 256                 netdev_for_each_mc_addr(ha, dev)
 257                         __set_bit(ipvlan_mac_hash(ha->addr), mc_filters);
 258
 259                 /* Turn-on broadcast bit irrespective of address family,
 260                  * since broadcast is deferred to a work-queue, hence no
 261                  * impact on fast-path processing.
 262                  */
 263                 __set_bit(ipvlan_mac_hash(dev->broadcast), mc_filters);
 264
 265                 bitmap_copy(ipvlan->mac_filters, mc_filters,
 266                             IPVLAN_MAC_FILTER_SIZE);
 267         }
 268         dev_uc_sync(ipvlan->phy_dev, dev);
 269         dev_mc_sync(ipvlan->phy_dev, dev);
 270 }
 271
 272 static void ipvlan_get_stats64(struct net_device *dev,
 273                                struct rtnl_link_stats64 *s)
 274 {
 275         struct ipvl_dev *ipvlan = netdev_priv(dev);
 276
 277         if (ipvlan->pcpu_stats) {
 278                 struct ipvl_pcpu_stats *pcptr;
 279                 u64 rx_pkts, rx_bytes, rx_mcast, tx_pkts, tx_bytes;
 280                 u32 rx_errs = 0, tx_drps = 0;
 281                 u32 strt;
 282                 int idx;
 283
 284                 for_each_possible_cpu(idx) {
 285                         pcptr = per_cpu_ptr(ipvlan->pcpu_stats, idx);
 286                         do {
 287                                 strt= u64_stats_fetch_begin_irq(&pcptr->syncp);
 288                                 rx_pkts = pcptr->rx_pkts;
 289                                 rx_bytes = pcptr->rx_bytes;
 290                                 rx_mcast = pcptr->rx_mcast;
 291                                 tx_pkts = pcptr->tx_pkts;
 292                                 tx_bytes = pcptr->tx_bytes;
 293                         } while (u64_stats_fetch_retry_irq(&pcptr->syncp,
 294                                                            strt));
 295
 296                         s->rx_packets += rx_pkts;
 297                         s->rx_bytes += rx_bytes;
 298                         s->multicast += rx_mcast;
 299                         s->tx_packets += tx_pkts;
 300                         s->tx_bytes += tx_bytes;
 301
 302                         /* u32 values are updated without syncp protection. */
 303                         rx_errs += pcptr->rx_errs;
 304                         tx_drps += pcptr->tx_drps;
 305                 }
 306                 s->rx_errors = rx_errs;
 307                 s->rx_dropped = rx_errs;
 308                 s->tx_dropped = tx_drps;
 309         }
 310 }
 311
 312 static int ipvlan_vlan_rx_add_vid(struct net_device *dev, __be16 proto, u16 vid)
 313 {
 314         struct ipvl_dev *ipvlan = netdev_priv(dev);
 315         struct net_device *phy_dev = ipvlan->phy_dev;
 316
 317         return vlan_vid_add(phy_dev, proto, vid);
 318 }
 319
 320 static int ipvlan_vlan_rx_kill_vid(struct net_device *dev, __be16 proto,
 321                                    u16 vid)
 322 {
 323         struct ipvl_dev *ipvlan = netdev_priv(dev);
 324         struct net_device *phy_dev = ipvlan->phy_dev;
 325
 326         vlan_vid_del(phy_dev, proto, vid);
 327         return 0;
 328 }
 329
 330 static int ipvlan_get_iflink(const struct net_device *dev)
 331 {
 332         struct ipvl_dev *ipvlan = netdev_priv(dev);
 333
 334         return ipvlan->phy_dev->ifindex;
 335 }
 336
 337 static const struct net_device_ops ipvlan_netdev_ops = {
 338         .ndo_init               = ipvlan_init,
 339         .ndo_uninit             = ipvlan_uninit,
 340         .ndo_open               = ipvlan_open,
 341         .ndo_stop               = ipvlan_stop,
 342         .ndo_start_xmit         = ipvlan_start_xmit,
 343         .ndo_fix_features       = ipvlan_fix_features,
 344         .ndo_change_rx_flags    = ipvlan_change_rx_flags,
 345         .ndo_set_rx_mode        = ipvlan_set_multicast_mac_filter,
 346         .ndo_get_stats64        = ipvlan_get_stats64,
 347         .ndo_vlan_rx_add_vid    = ipvlan_vlan_rx_add_vid,
 348         .ndo_vlan_rx_kill_vid   = ipvlan_vlan_rx_kill_vid,
 349         .ndo_get_iflink         = ipvlan_get_iflink,
 350 };
 351
 352 static int ipvlan_hard_header(struct sk_buff *skb, struct net_device *dev,
 353                               unsigned short type, const void *daddr,
 354                               const void *saddr, unsigned len)
 355 {
 356         const struct ipvl_dev *ipvlan = netdev_priv(dev);
 357         struct net_device *phy_dev = ipvlan->phy_dev;
 358
 359         /* TODO Probably use a different field than dev_addr so that the
 360          * mac-address on the virtual device is portable and can be carried
 361          * while the packets use the mac-addr on the physical device.
 362          */
 363         return dev_hard_header(skb, phy_dev, type, daddr,
 364                                saddr ? : phy_dev->dev_addr, len);
 365 }
 366
 367 static const struct header_ops ipvlan_header_ops = {
 368         .create         = ipvlan_hard_header,
 369         .parse          = eth_header_parse,
 370         .cache          = eth_header_cache,
 371         .cache_update   = eth_header_cache_update,
 372 };
 373
 374 static void ipvlan_adjust_mtu(struct ipvl_dev *ipvlan, struct net_device *dev)
 375 {
 376         ipvlan->dev->mtu = dev->mtu;
 377 }
 378
 379 static bool netif_is_ipvlan(const struct net_device *dev)
 380 {
 381         /* both ipvlan and ipvtap devices use the same netdev_ops */
 382         return dev->netdev_ops == &ipvlan_netdev_ops;
 383 }
 384
 385 static int ipvlan_ethtool_get_link_ksettings(struct net_device *dev,
 386                                              struct ethtool_link_ksettings *cmd)
 387 {
 388         const struct ipvl_dev *ipvlan = netdev_priv(dev);
 389
 390         return __ethtool_get_link_ksettings(ipvlan->phy_dev, cmd);
 391 }
 392
 393 static void ipvlan_ethtool_get_drvinfo(struct net_device *dev,
 394                                        struct ethtool_drvinfo *drvinfo)
 395 {
 396         strlcpy(drvinfo->driver, IPVLAN_DRV, sizeof(drvinfo->driver));
 397         strlcpy(drvinfo->version, IPV_DRV_VER, sizeof(drvinfo->version));
 398 }
 399
 400 static u32 ipvlan_ethtool_get_msglevel(struct net_device *dev)
 401 {
 402         const struct ipvl_dev *ipvlan = netdev_priv(dev);
 403
 404         return ipvlan->msg_enable;
 405 }
 406
 407 static void ipvlan_ethtool_set_msglevel(struct net_device *dev, u32 value)
 408 {
 409         struct ipvl_dev *ipvlan = netdev_priv(dev);
 410
 411         ipvlan->msg_enable = value;
 412 }
 413
 414 static const struct ethtool_ops ipvlan_ethtool_ops = {
 415         .get_link       = ethtool_op_get_link,
 416         .get_link_ksettings     = ipvlan_ethtool_get_link_ksettings,
 417         .get_drvinfo    = ipvlan_ethtool_get_drvinfo,
 418         .get_msglevel   = ipvlan_ethtool_get_msglevel,
 419         .set_msglevel   = ipvlan_ethtool_set_msglevel,
 420 };
 421
 422 static int ipvlan_nl_changelink(struct net_device *dev,
 423                                 struct nlattr *tb[], struct nlattr *data[],
 424                                 struct netlink_ext_ack *extack)
 425 {
 426         struct ipvl_dev *ipvlan = netdev_priv(dev);
 427         struct ipvl_port *port = ipvlan_port_get_rtnl(ipvlan->phy_dev);
 428         int err = 0;
 429
 430         if (!data)
 431                 return 0;
 432         if (!ns_capable(dev_net(ipvlan->phy_dev)->user_ns, CAP_NET_ADMIN))
 433                 return -EPERM;
 434
 435         if (data[IFLA_IPVLAN_MODE]) {
 436                 u16 nmode = nla_get_u16(data[IFLA_IPVLAN_MODE]);
 437
 438                 err = ipvlan_set_port_mode(port, nmode, extack);
 439         }
 440
 441         if (!err && data[IFLA_IPVLAN_FLAGS]) {
 442                 u16 flags = nla_get_u16(data[IFLA_IPVLAN_FLAGS]);
 443
 444                 if (flags & IPVLAN_F_PRIVATE)
 445                         ipvlan_mark_private(port);
 446                 else
 447                         ipvlan_clear_private(port);
 448
 449                 if (flags & IPVLAN_F_VEPA)
 450                         ipvlan_mark_vepa(port);
 451                 else
 452                         ipvlan_clear_vepa(port);
 453         }
 454
 455         return err;
 456 }
 457
 458 static size_t ipvlan_nl_getsize(const struct net_device *dev)
 459 {
 460         return (0
 461                 + nla_total_size(2) /* IFLA_IPVLAN_MODE */
 462                 + nla_total_size(2) /* IFLA_IPVLAN_FLAGS */
 463                 );
 464 }
 465
 466 static int ipvlan_nl_validate(struct nlattr *tb[], struct nlattr *data[],
 467                               struct netlink_ext_ack *extack)
 468 {
 469         if (!data)
 470                 return 0;
 471
 472         if (data[IFLA_IPVLAN_MODE]) {
 473                 u16 mode = nla_get_u16(data[IFLA_IPVLAN_MODE]);
 474
 475                 if (mode >= IPVLAN_MODE_MAX)
 476                         return -EINVAL;
 477         }
 478         if (data[IFLA_IPVLAN_FLAGS]) {
 479                 u16 flags = nla_get_u16(data[IFLA_IPVLAN_FLAGS]);
 480
 481                 /* Only two bits are used at this moment. */
 482                 if (flags & ~(IPVLAN_F_PRIVATE | IPVLAN_F_VEPA))
 483                         return -EINVAL;
 484                 /* Also both flags can't be active at the same time. */
 485                 if ((flags & (IPVLAN_F_PRIVATE | IPVLAN_F_VEPA)) ==
 486                     (IPVLAN_F_PRIVATE | IPVLAN_F_VEPA))
 487                         return -EINVAL;
 488         }
 489
 490         return 0;
 491 }
 492
 493 static int ipvlan_nl_fillinfo(struct sk_buff *skb,
 494                               const struct net_device *dev)
 495 {
 496         struct ipvl_dev *ipvlan = netdev_priv(dev);
 497         struct ipvl_port *port = ipvlan_port_get_rtnl(ipvlan->phy_dev);
 498         int ret = -EINVAL;
 499
 500         if (!port)
 501                 goto err;
 502
 503         ret = -EMSGSIZE;
 504         if (nla_put_u16(skb, IFLA_IPVLAN_MODE, port->mode))
 505                 goto err;
 506         if (nla_put_u16(skb, IFLA_IPVLAN_FLAGS, port->flags))
 507                 goto err;
 508
 509         return 0;
 510
 511 err:
 512         return ret;
 513 }
 514
 515 int ipvlan_link_new(struct net *src_net, struct net_device *dev,
 516                     struct nlattr *tb[], struct nlattr *data[],
 517                     struct netlink_ext_ack *extack)
 518 {
 519         struct ipvl_dev *ipvlan = netdev_priv(dev);
 520         struct ipvl_port *port;
 521         struct net_device *phy_dev;
 522         int err;
 523         u16 mode = IPVLAN_MODE_L3;
 524
 525         if (!tb[IFLA_LINK])
 526                 return -EINVAL;
 527
 528         phy_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
 529         if (!phy_dev)
 530                 return -ENODEV;
 531
 532         if (netif_is_ipvlan(phy_dev)) {
 533                 struct ipvl_dev *tmp = netdev_priv(phy_dev);
 534
 535                 phy_dev = tmp->phy_dev;
 536                 if (!ns_capable(dev_net(phy_dev)->user_ns, CAP_NET_ADMIN))
 537                         return -EPERM;
 538         } else if (!netif_is_ipvlan_port(phy_dev)) {
 539                 /* Exit early if the underlying link is invalid or busy */
 540                 if (phy_dev->type != ARPHRD_ETHER ||
 541                     phy_dev->flags & IFF_LOOPBACK) {
 542                         netdev_err(phy_dev,
 543                                    "Master is either lo or non-ether device\n");
 544                         return -EINVAL;
 545                 }
 546
 547                 if (netdev_is_rx_handler_busy(phy_dev)) {
 548                         netdev_err(phy_dev, "Device is already in use.\n");
 549                         return -EBUSY;
 550                 }
 551         }
 552
 553         ipvlan->phy_dev = phy_dev;
 554         ipvlan->dev = dev;
 555         ipvlan->sfeatures = IPVLAN_FEATURES;
 556         if (!tb[IFLA_MTU])
 557                 ipvlan_adjust_mtu(ipvlan, phy_dev);
 558         INIT_LIST_HEAD(&ipvlan->addrs);
 559         spin_lock_init(&ipvlan->addrs_lock);
 560
 561         /* TODO Probably put random address here to be presented to the
 562          * world but keep using the physical-dev address for the outgoing
 563          * packets.
 564          */
 565         memcpy(dev->dev_addr, phy_dev->dev_addr, ETH_ALEN);
 566
 567         dev->priv_flags |= IFF_NO_RX_HANDLER;
 568
 569         err = register_netdevice(dev);
 570         if (err < 0)
 571                 return err;
 572
 573         /* ipvlan_init() would have created the port, if required */
 574         port = ipvlan_port_get_rtnl(phy_dev);
 575         ipvlan->port = port;
 576
 577         /* If the port-id base is at the MAX value, then wrap it around and
 578          * begin from 0x1 again. This may be due to a busy system where lots
 579          * of slaves are getting created and deleted.
 580          */
 581         if (port->dev_id_start == 0xFFFE)
 582                 port->dev_id_start = 0x1;
 583
 584         /* Since L2 address is shared among all IPvlan slaves including
 585          * master, use unique 16 bit dev-ids to diffentiate among them.
 586          * Assign IDs between 0x1 and 0xFFFE (used by the master) to each
 587          * slave link [see addrconf_ifid_eui48()].
 588          */
 589         err = ida_simple_get(&port->ida, port->dev_id_start, 0xFFFE,
 590                              GFP_KERNEL);
 591         if (err < 0)
 592                 err = ida_simple_get(&port->ida, 0x1, port->dev_id_start,
 593                                      GFP_KERNEL);
 594         if (err < 0)
 595                 goto unregister_netdev;
 596         dev->dev_id = err;
 597
 598         /* Increment id-base to the next slot for the future assignment */
 599         port->dev_id_start = err + 1;
 600
 601         err = netdev_upper_dev_link(phy_dev, dev, extack);
 602         if (err)
 603                 goto remove_ida;
 604
 605         /* Flags are per port and latest update overrides. User has
 606          * to be consistent in setting it just like the mode attribute.
 607          */
 608         if (data && data[IFLA_IPVLAN_FLAGS])
 609                 port->flags = nla_get_u16(data[IFLA_IPVLAN_FLAGS]);
 610
 611         if (data && data[IFLA_IPVLAN_MODE])
 612                 mode = nla_get_u16(data[IFLA_IPVLAN_MODE]);
 613
 614         err = ipvlan_set_port_mode(port, mode, extack);
 615         if (err)
 616                 goto unlink_netdev;
 617
 618         list_add_tail_rcu(&ipvlan->pnode, &port->ipvlans);
 619         netif_stacked_transfer_operstate(phy_dev, dev);
 620         return 0;
 621
 622 unlink_netdev:
 623         netdev_upper_dev_unlink(phy_dev, dev);
 624 remove_ida:
 625         ida_simple_remove(&port->ida, dev->dev_id);
 626 unregister_netdev:
 627         unregister_netdevice(dev);
 628         return err;
 629 }
 630 EXPORT_SYMBOL_GPL(ipvlan_link_new);
 631
 632 void ipvlan_link_delete(struct net_device *dev, struct list_head *head)
 633 {
 634         struct ipvl_dev *ipvlan = netdev_priv(dev);
 635         struct ipvl_addr *addr, *next;
 636
 637         spin_lock_bh(&ipvlan->addrs_lock);
 638         list_for_each_entry_safe(addr, next, &ipvlan->addrs, anode) {
 639                 ipvlan_ht_addr_del(addr);
 640                 list_del_rcu(&addr->anode);
 641                 kfree_rcu(addr, rcu);
 642         }
 643         spin_unlock_bh(&ipvlan->addrs_lock);
 644
 645         ida_simple_remove(&ipvlan->port->ida, dev->dev_id);
 646         list_del_rcu(&ipvlan->pnode);
 647         unregister_netdevice_queue(dev, head);
 648         netdev_upper_dev_unlink(ipvlan->phy_dev, dev);
 649 }
 650 EXPORT_SYMBOL_GPL(ipvlan_link_delete);
 651
 652 void ipvlan_link_setup(struct net_device *dev)
 653 {
 654         ether_setup(dev);
 655
 656         dev->max_mtu = ETH_MAX_MTU;
 657         dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
 658         dev->priv_flags |= IFF_UNICAST_FLT | IFF_NO_QUEUE;
 659         dev->netdev_ops = &ipvlan_netdev_ops;
 660         dev->needs_free_netdev = true;
 661         dev->header_ops = &ipvlan_header_ops;
 662         dev->ethtool_ops = &ipvlan_ethtool_ops;
 663 }
 664 EXPORT_SYMBOL_GPL(ipvlan_link_setup);
 665
 666 static const struct nla_policy ipvlan_nl_policy[IFLA_IPVLAN_MAX + 1] =
 667 {
 668         [IFLA_IPVLAN_MODE] = { .type = NLA_U16 },
 669         [IFLA_IPVLAN_FLAGS] = { .type = NLA_U16 },
 670 };
 671
 672 static struct rtnl_link_ops ipvlan_link_ops = {
 673         .kind           = "ipvlan",
 674         .priv_size      = sizeof(struct ipvl_dev),
 675
 676         .setup          = ipvlan_link_setup,
 677         .newlink        = ipvlan_link_new,
 678         .dellink        = ipvlan_link_delete,
 679 };
 680
 681 int ipvlan_link_register(struct rtnl_link_ops *ops)
 682 {
 683         ops->get_size   = ipvlan_nl_getsize;
 684         ops->policy     = ipvlan_nl_policy;
 685         ops->validate   = ipvlan_nl_validate;
 686         ops->fill_info  = ipvlan_nl_fillinfo;
 687         ops->changelink = ipvlan_nl_changelink;
 688         ops->maxtype    = IFLA_IPVLAN_MAX;
 689         return rtnl_link_register(ops);
 690 }
 691 EXPORT_SYMBOL_GPL(ipvlan_link_register);
 692
 693 static int ipvlan_device_event(struct notifier_block *unused,
 694                                unsigned long event, void *ptr)
 695 {
 696         struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr);
 697         struct netdev_notifier_pre_changeaddr_info *prechaddr_info;
 698         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 699         struct ipvl_dev *ipvlan, *next;
 700         struct ipvl_port *port;
 701         LIST_HEAD(lst_kill);
 702         int err;
 703
 704         if (!netif_is_ipvlan_port(dev))
 705                 return NOTIFY_DONE;
 706
 707         port = ipvlan_port_get_rtnl(dev);
 708
 709         switch (event) {
 710         case NETDEV_CHANGE:
 711                 list_for_each_entry(ipvlan, &port->ipvlans, pnode)
 712                         netif_stacked_transfer_operstate(ipvlan->phy_dev,
 713                                                          ipvlan->dev);
 714                 break;
 715
 716         case NETDEV_REGISTER: {
 717                 struct net *oldnet, *newnet = dev_net(dev);
 718
 719                 oldnet = read_pnet(&port->pnet);
 720                 if (net_eq(newnet, oldnet))
 721                         break;
 722
 723                 write_pnet(&port->pnet, newnet);
 724
 725                 ipvlan_migrate_l3s_hook(oldnet, newnet);
 726                 break;
 727         }
 728         case NETDEV_UNREGISTER:
 729                 if (dev->reg_state != NETREG_UNREGISTERING)
 730                         break;
 731
 732                 list_for_each_entry_safe(ipvlan, next, &port->ipvlans, pnode)
 733                         ipvlan->dev->rtnl_link_ops->dellink(ipvlan->dev,
 734                                                             &lst_kill);
 735                 unregister_netdevice_many(&lst_kill);
 736                 break;
 737
 738         case NETDEV_FEAT_CHANGE:
 739                 list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
 740                         ipvlan->dev->features = dev->features & IPVLAN_FEATURES;
 741                         ipvlan->dev->gso_max_size = dev->gso_max_size;
 742                         ipvlan->dev->gso_max_segs = dev->gso_max_segs;
 743                         netdev_features_change(ipvlan->dev);
 744                 }
 745                 break;
 746
 747         case NETDEV_CHANGEMTU:
 748                 list_for_each_entry(ipvlan, &port->ipvlans, pnode)
 749                         ipvlan_adjust_mtu(ipvlan, dev);
 750                 break;
 751
 752         case NETDEV_PRE_CHANGEADDR:
 753                 prechaddr_info = ptr;
 754                 list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
 755                         err = dev_pre_changeaddr_notify(ipvlan->dev,
 756                                                     prechaddr_info->dev_addr,
 757                                                     extack);
 758                         if (err)
 759                                 return notifier_from_errno(err);
 760                 }
 761                 break;
 762
 763         case NETDEV_CHANGEADDR:
 764                 list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
 765                         ether_addr_copy(ipvlan->dev->dev_addr, dev->dev_addr);
 766                         call_netdevice_notifiers(NETDEV_CHANGEADDR, ipvlan->dev);
 767                 }
 768                 break;
 769
 770         case NETDEV_PRE_TYPE_CHANGE:
 771                 /* Forbid underlying device to change its type. */
 772                 return NOTIFY_BAD;
 773         }
 774         return NOTIFY_DONE;
 775 }
 776
 777 /* the caller must held the addrs lock */
 778 static int ipvlan_add_addr(struct ipvl_dev *ipvlan, void *iaddr, bool is_v6)
 779 {
 780         struct ipvl_addr *addr;
 781
 782         addr = kzalloc(sizeof(struct ipvl_addr), GFP_ATOMIC);
 783         if (!addr)
 784                 return -ENOMEM;
 785
 786         addr->master = ipvlan;
 787         if (!is_v6) {
 788                 memcpy(&addr->ip4addr, iaddr, sizeof(struct in_addr));
 789                 addr->atype = IPVL_IPV4;
 790 #if IS_ENABLED(CONFIG_IPV6)
 791         } else {
 792                 memcpy(&addr->ip6addr, iaddr, sizeof(struct in6_addr));
 793                 addr->atype = IPVL_IPV6;
 794 #endif
 795         }
 796
 797         list_add_tail_rcu(&addr->anode, &ipvlan->addrs);
 798
 799         /* If the interface is not up, the address will be added to the hash
 800          * list by ipvlan_open.
 801          */
 802         if (netif_running(ipvlan->dev))
 803                 ipvlan_ht_addr_add(ipvlan, addr);
 804
 805         return 0;
 806 }
 807
 808 static void ipvlan_del_addr(struct ipvl_dev *ipvlan, void *iaddr, bool is_v6)
 809 {
 810         struct ipvl_addr *addr;
 811
 812         spin_lock_bh(&ipvlan->addrs_lock);
 813         addr = ipvlan_find_addr(ipvlan, iaddr, is_v6);
 814         if (!addr) {
 815                 spin_unlock_bh(&ipvlan->addrs_lock);
 816                 return;
 817         }
 818
 819         ipvlan_ht_addr_del(addr);
 820         list_del_rcu(&addr->anode);
 821         spin_unlock_bh(&ipvlan->addrs_lock);
 822         kfree_rcu(addr, rcu);
 823 }
 824
 825 static bool ipvlan_is_valid_dev(const struct net_device *dev)
 826 {
 827         struct ipvl_dev *ipvlan = netdev_priv(dev);
 828
 829         if (!netif_is_ipvlan(dev))
 830                 return false;
 831
 832         if (!ipvlan || !ipvlan->port)
 833                 return false;
 834
 835         return true;
 836 }
 837
 838 #if IS_ENABLED(CONFIG_IPV6)
 839 static int ipvlan_add_addr6(struct ipvl_dev *ipvlan, struct in6_addr *ip6_addr)
 840 {
 841         int ret = -EINVAL;
 842
 843         spin_lock_bh(&ipvlan->addrs_lock);
 844         if (ipvlan_addr_busy(ipvlan->port, ip6_addr, true))
 845                 netif_err(ipvlan, ifup, ipvlan->dev,
 846                           "Failed to add IPv6=%pI6c addr for %s intf\n",
 847                           ip6_addr, ipvlan->dev->name);
 848         else
 849                 ret = ipvlan_add_addr(ipvlan, ip6_addr, true);
 850         spin_unlock_bh(&ipvlan->addrs_lock);
 851         return ret;
 852 }
 853
 854 static void ipvlan_del_addr6(struct ipvl_dev *ipvlan, struct in6_addr *ip6_addr)
 855 {
 856         return ipvlan_del_addr(ipvlan, ip6_addr, true);
 857 }
 858
 859 static int ipvlan_addr6_event(struct notifier_block *unused,
 860                               unsigned long event, void *ptr)
 861 {
 862         struct inet6_ifaddr *if6 = (struct inet6_ifaddr *)ptr;
 863         struct net_device *dev = (struct net_device *)if6->idev->dev;
 864         struct ipvl_dev *ipvlan = netdev_priv(dev);
 865
 866         if (!ipvlan_is_valid_dev(dev))
 867                 return NOTIFY_DONE;
 868
 869         switch (event) {
 870         case NETDEV_UP:
 871                 if (ipvlan_add_addr6(ipvlan, &if6->addr))
 872                         return NOTIFY_BAD;
 873                 break;
 874
 875         case NETDEV_DOWN:
 876                 ipvlan_del_addr6(ipvlan, &if6->addr);
 877                 break;
 878         }
 879
 880         return NOTIFY_OK;
 881 }
 882
 883 static int ipvlan_addr6_validator_event(struct notifier_block *unused,
 884                                         unsigned long event, void *ptr)
 885 {
 886         struct in6_validator_info *i6vi = (struct in6_validator_info *)ptr;
 887         struct net_device *dev = (struct net_device *)i6vi->i6vi_dev->dev;
 888         struct ipvl_dev *ipvlan = netdev_priv(dev);
 889
 890         if (!ipvlan_is_valid_dev(dev))
 891                 return NOTIFY_DONE;
 892
 893         switch (event) {
 894         case NETDEV_UP:
 895                 if (ipvlan_addr_busy(ipvlan->port, &i6vi->i6vi_addr, true)) {
 896                         NL_SET_ERR_MSG(i6vi->extack,
 897                                        "Address already assigned to an ipvlan device");
 898                         return notifier_from_errno(-EADDRINUSE);
 899                 }
 900                 break;
 901         }
 902
 903         return NOTIFY_OK;
 904 }
 905 #endif
 906
 907 static int ipvlan_add_addr4(struct ipvl_dev *ipvlan, struct in_addr *ip4_addr)
 908 {
 909         int ret = -EINVAL;
 910
 911         spin_lock_bh(&ipvlan->addrs_lock);
 912         if (ipvlan_addr_busy(ipvlan->port, ip4_addr, false))
 913                 netif_err(ipvlan, ifup, ipvlan->dev,
 914                           "Failed to add IPv4=%pI4 on %s intf.\n",
 915                           ip4_addr, ipvlan->dev->name);
 916         else
 917                 ret = ipvlan_add_addr(ipvlan, ip4_addr, false);
 918         spin_unlock_bh(&ipvlan->addrs_lock);
 919         return ret;
 920 }
 921
 922 static void ipvlan_del_addr4(struct ipvl_dev *ipvlan, struct in_addr *ip4_addr)
 923 {
 924         return ipvlan_del_addr(ipvlan, ip4_addr, false);
 925 }
 926
 927 static int ipvlan_addr4_event(struct notifier_block *unused,
 928                               unsigned long event, void *ptr)
 929 {
 930         struct in_ifaddr *if4 = (struct in_ifaddr *)ptr;
 931         struct net_device *dev = (struct net_device *)if4->ifa_dev->dev;
 932         struct ipvl_dev *ipvlan = netdev_priv(dev);
 933         struct in_addr ip4_addr;
 934
 935         if (!ipvlan_is_valid_dev(dev))
 936                 return NOTIFY_DONE;
 937
 938         switch (event) {
 939         case NETDEV_UP:
 940                 ip4_addr.s_addr = if4->ifa_address;
 941                 if (ipvlan_add_addr4(ipvlan, &ip4_addr))
 942                         return NOTIFY_BAD;
 943                 break;
 944
 945         case NETDEV_DOWN:
 946                 ip4_addr.s_addr = if4->ifa_address;
 947                 ipvlan_del_addr4(ipvlan, &ip4_addr);
 948                 break;
 949         }
 950
 951         return NOTIFY_OK;
 952 }
 953
 954 static int ipvlan_addr4_validator_event(struct notifier_block *unused,
 955                                         unsigned long event, void *ptr)
 956 {
 957         struct in_validator_info *ivi = (struct in_validator_info *)ptr;
 958         struct net_device *dev = (struct net_device *)ivi->ivi_dev->dev;
 959         struct ipvl_dev *ipvlan = netdev_priv(dev);
 960
 961         if (!ipvlan_is_valid_dev(dev))
 962                 return NOTIFY_DONE;
 963
 964         switch (event) {
 965         case NETDEV_UP:
 966                 if (ipvlan_addr_busy(ipvlan->port, &ivi->ivi_addr, false)) {
 967                         NL_SET_ERR_MSG(ivi->extack,
 968                                        "Address already assigned to an ipvlan device");
 969                         return notifier_from_errno(-EADDRINUSE);
 970                 }
 971                 break;
 972         }
 973
 974         return NOTIFY_OK;
 975 }
 976
 977 static struct notifier_block ipvlan_addr4_notifier_block __read_mostly = {
 978         .notifier_call = ipvlan_addr4_event,
 979 };
 980
 981 static struct notifier_block ipvlan_addr4_vtor_notifier_block __read_mostly = {
 982         .notifier_call = ipvlan_addr4_validator_event,
 983 };
 984
 985 static struct notifier_block ipvlan_notifier_block __read_mostly = {
 986         .notifier_call = ipvlan_device_event,
 987 };
 988
 989 #if IS_ENABLED(CONFIG_IPV6)
 990 static struct notifier_block ipvlan_addr6_notifier_block __read_mostly = {
 991         .notifier_call = ipvlan_addr6_event,
 992 };
 993
 994 static struct notifier_block ipvlan_addr6_vtor_notifier_block __read_mostly = {
 995         .notifier_call = ipvlan_addr6_validator_event,
 996 };
 997 #endif
 998
 999 static int __init ipvlan_init_module(void)
1000 {
1001         int err;
1002
1003         ipvlan_init_secret();
1004         register_netdevice_notifier(&ipvlan_notifier_block);
1005 #if IS_ENABLED(CONFIG_IPV6)
1006         register_inet6addr_notifier(&ipvlan_addr6_notifier_block);
1007         register_inet6addr_validator_notifier(
1008             &ipvlan_addr6_vtor_notifier_block);
1009 #endif
1010         register_inetaddr_notifier(&ipvlan_addr4_notifier_block);
1011         register_inetaddr_validator_notifier(&ipvlan_addr4_vtor_notifier_block);
1012
1013         err = ipvlan_l3s_init();
1014         if (err < 0)
1015                 goto error;
1016
1017         err = ipvlan_link_register(&ipvlan_link_ops);
1018         if (err < 0) {
1019                 ipvlan_l3s_cleanup();
1020                 goto error;
1021         }
1022
1023         return 0;
1024 error:
1025         unregister_inetaddr_notifier(&ipvlan_addr4_notifier_block);
1026         unregister_inetaddr_validator_notifier(
1027             &ipvlan_addr4_vtor_notifier_block);
1028 #if IS_ENABLED(CONFIG_IPV6)
1029         unregister_inet6addr_notifier(&ipvlan_addr6_notifier_block);
1030         unregister_inet6addr_validator_notifier(
1031             &ipvlan_addr6_vtor_notifier_block);
1032 #endif
1033         unregister_netdevice_notifier(&ipvlan_notifier_block);
1034         return err;
1035 }
1036
1037 static void __exit ipvlan_cleanup_module(void)
1038 {
1039         rtnl_link_unregister(&ipvlan_link_ops);
1040         ipvlan_l3s_cleanup();
1041         unregister_netdevice_notifier(&ipvlan_notifier_block);
1042         unregister_inetaddr_notifier(&ipvlan_addr4_notifier_block);
1043         unregister_inetaddr_validator_notifier(
1044             &ipvlan_addr4_vtor_notifier_block);
1045 #if IS_ENABLED(CONFIG_IPV6)
1046         unregister_inet6addr_notifier(&ipvlan_addr6_notifier_block);
1047         unregister_inet6addr_validator_notifier(
1048             &ipvlan_addr6_vtor_notifier_block);
1049 #endif
1050 }
1051
1052 module_init(ipvlan_init_module);
1053 module_exit(ipvlan_cleanup_module);
1054
1055 MODULE_LICENSE("GPL");
1056 MODULE_AUTHOR("Mahesh Bandewar <maheshb@google.com>");
1057 MODULE_DESCRIPTION("Driver for L3 (IPv6/IPv4) based VLANs");
1058 MODULE_ALIAS_RTNL_LINK("ipvlan");