drivers/net/bareudp.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Bareudp: UDP  tunnel encasulation for different Payload types like
   3  * MPLS, NSH, IP, etc.
   4  * Copyright (c) 2019 Nokia, Inc.
   5  * Authors:  Martin Varghese, <martin.varghese@nokia.com>
   6  */
   7
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/etherdevice.h>
  13 #include <linux/hash.h>
  14 #include <net/dst_metadata.h>
  15 #include <net/gro_cells.h>
  16 #include <net/rtnetlink.h>
  17 #include <net/protocol.h>
  18 #include <net/ip6_tunnel.h>
  19 #include <net/ip_tunnels.h>
  20 #include <net/udp_tunnel.h>
  21 #include <net/bareudp.h>
  22
  23 #define BAREUDP_BASE_HLEN sizeof(struct udphdr)
  24 #define BAREUDP_IPV4_HLEN (sizeof(struct iphdr) + \
  25                            sizeof(struct udphdr))
  26 #define BAREUDP_IPV6_HLEN (sizeof(struct ipv6hdr) + \
  27                            sizeof(struct udphdr))
  28
  29 static bool log_ecn_error = true;
  30 module_param(log_ecn_error, bool, 0644);
  31 MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
  32
  33 /* per-network namespace private data for this module */
  34
  35 static unsigned int bareudp_net_id;
  36
  37 struct bareudp_net {
  38         struct list_head        bareudp_list;
  39 };
  40
  41 /* Pseudo network device */
  42 struct bareudp_dev {
  43         struct net         *net;        /* netns for packet i/o */
  44         struct net_device  *dev;        /* netdev for bareudp tunnel */
  45         __be16             ethertype;
  46         __be16             port;
  47         u16                sport_min;
  48         bool               multi_proto_mode;
  49         struct socket      __rcu *sock;
  50         struct list_head   next;        /* bareudp node  on namespace list */
  51         struct gro_cells   gro_cells;
  52 };
  53
  54 static int bareudp_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
  55 {
  56         struct metadata_dst *tun_dst = NULL;
  57         struct bareudp_dev *bareudp;
  58         unsigned short family;
  59         unsigned int len;
  60         __be16 proto;
  61         void *oiph;
  62         int err;
  63
  64         bareudp = rcu_dereference_sk_user_data(sk);
  65         if (!bareudp)
  66                 goto drop;
  67
  68         if (skb->protocol ==  htons(ETH_P_IP))
  69                 family = AF_INET;
  70         else
  71                 family = AF_INET6;
  72
  73         if (bareudp->ethertype == htons(ETH_P_IP)) {
  74                 struct iphdr *iphdr;
  75
  76                 iphdr = (struct iphdr *)(skb->data + BAREUDP_BASE_HLEN);
  77                 if (iphdr->version == 4) {
  78                         proto = bareudp->ethertype;
  79                 } else if (bareudp->multi_proto_mode && (iphdr->version == 6)) {
  80                         proto = htons(ETH_P_IPV6);
  81                 } else {
  82                         bareudp->dev->stats.rx_dropped++;
  83                         goto drop;
  84                 }
  85         } else if (bareudp->ethertype == htons(ETH_P_MPLS_UC)) {
  86                 struct iphdr *tunnel_hdr;
  87
  88                 tunnel_hdr = (struct iphdr *)skb_network_header(skb);
  89                 if (tunnel_hdr->version == 4) {
  90                         if (!ipv4_is_multicast(tunnel_hdr->daddr)) {
  91                                 proto = bareudp->ethertype;
  92                         } else if (bareudp->multi_proto_mode &&
  93                                    ipv4_is_multicast(tunnel_hdr->daddr)) {
  94                                 proto = htons(ETH_P_MPLS_MC);
  95                         } else {
  96                                 bareudp->dev->stats.rx_dropped++;
  97                                 goto drop;
  98                         }
  99                 } else {
 100                         int addr_type;
 101                         struct ipv6hdr *tunnel_hdr_v6;
 102
 103                         tunnel_hdr_v6 = (struct ipv6hdr *)skb_network_header(skb);
 104                         addr_type =
 105                         ipv6_addr_type((struct in6_addr *)&tunnel_hdr_v6->daddr);
 106                         if (!(addr_type & IPV6_ADDR_MULTICAST)) {
 107                                 proto = bareudp->ethertype;
 108                         } else if (bareudp->multi_proto_mode &&
 109                                    (addr_type & IPV6_ADDR_MULTICAST)) {
 110                                 proto = htons(ETH_P_MPLS_MC);
 111                         } else {
 112                                 bareudp->dev->stats.rx_dropped++;
 113                                 goto drop;
 114                         }
 115                 }
 116         } else {
 117                 proto = bareudp->ethertype;
 118         }
 119
 120         if (iptunnel_pull_header(skb, BAREUDP_BASE_HLEN,
 121                                  proto,
 122                                  !net_eq(bareudp->net,
 123                                  dev_net(bareudp->dev)))) {
 124                 bareudp->dev->stats.rx_dropped++;
 125                 goto drop;
 126         }
 127         tun_dst = udp_tun_rx_dst(skb, family, TUNNEL_KEY, 0, 0);
 128         if (!tun_dst) {
 129                 bareudp->dev->stats.rx_dropped++;
 130                 goto drop;
 131         }
 132         skb_dst_set(skb, &tun_dst->dst);
 133         skb->dev = bareudp->dev;
 134         oiph = skb_network_header(skb);
 135         skb_reset_network_header(skb);
 136
 137         if (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET)
 138                 err = IP_ECN_decapsulate(oiph, skb);
 139         else
 140                 err = IP6_ECN_decapsulate(oiph, skb);
 141
 142         if (unlikely(err)) {
 143                 if (log_ecn_error) {
 144                         if  (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET)
 145                                 net_info_ratelimited("non-ECT from %pI4 "
 146                                                      "with TOS=%#x\n",
 147                                                      &((struct iphdr *)oiph)->saddr,
 148                                                      ((struct iphdr *)oiph)->tos);
 149                         else
 150                                 net_info_ratelimited("non-ECT from %pI6\n",
 151                                                      &((struct ipv6hdr *)oiph)->saddr);
 152                 }
 153                 if (err > 1) {
 154                         ++bareudp->dev->stats.rx_frame_errors;
 155                         ++bareudp->dev->stats.rx_errors;
 156                         goto drop;
 157                 }
 158         }
 159
 160         len = skb->len;
 161         err = gro_cells_receive(&bareudp->gro_cells, skb);
 162         if (likely(err == NET_RX_SUCCESS))
 163                 dev_sw_netstats_rx_add(bareudp->dev, len);
 164
 165         return 0;
 166 drop:
 167         /* Consume bad packet */
 168         kfree_skb(skb);
 169
 170         return 0;
 171 }
 172
 173 static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
 174 {
 175         return 0;
 176 }
 177
 178 static int bareudp_init(struct net_device *dev)
 179 {
 180         struct bareudp_dev *bareudp = netdev_priv(dev);
 181         int err;
 182
 183         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 184         if (!dev->tstats)
 185                 return -ENOMEM;
 186
 187         err = gro_cells_init(&bareudp->gro_cells, dev);
 188         if (err) {
 189                 free_percpu(dev->tstats);
 190                 return err;
 191         }
 192         return 0;
 193 }
 194
 195 static void bareudp_uninit(struct net_device *dev)
 196 {
 197         struct bareudp_dev *bareudp = netdev_priv(dev);
 198
 199         gro_cells_destroy(&bareudp->gro_cells);
 200         free_percpu(dev->tstats);
 201 }
 202
 203 static struct socket *bareudp_create_sock(struct net *net, __be16 port)
 204 {
 205         struct udp_port_cfg udp_conf;
 206         struct socket *sock;
 207         int err;
 208
 209         memset(&udp_conf, 0, sizeof(udp_conf));
 210 #if IS_ENABLED(CONFIG_IPV6)
 211         udp_conf.family = AF_INET6;
 212 #else
 213         udp_conf.family = AF_INET;
 214 #endif
 215         udp_conf.local_udp_port = port;
 216         /* Open UDP socket */
 217         err = udp_sock_create(net, &udp_conf, &sock);
 218         if (err < 0)
 219                 return ERR_PTR(err);
 220
 221         return sock;
 222 }
 223
 224 /* Create new listen socket if needed */
 225 static int bareudp_socket_create(struct bareudp_dev *bareudp, __be16 port)
 226 {
 227         struct udp_tunnel_sock_cfg tunnel_cfg;
 228         struct socket *sock;
 229
 230         sock = bareudp_create_sock(bareudp->net, port);
 231         if (IS_ERR(sock))
 232                 return PTR_ERR(sock);
 233
 234         /* Mark socket as an encapsulation socket */
 235         memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
 236         tunnel_cfg.sk_user_data = bareudp;
 237         tunnel_cfg.encap_type = 1;
 238         tunnel_cfg.encap_rcv = bareudp_udp_encap_recv;
 239         tunnel_cfg.encap_err_lookup = bareudp_err_lookup;
 240         tunnel_cfg.encap_destroy = NULL;
 241         setup_udp_tunnel_sock(bareudp->net, sock, &tunnel_cfg);
 242
 243         /* As the setup_udp_tunnel_sock does not call udp_encap_enable if the
 244          * socket type is v6 an explicit call to udp_encap_enable is needed.
 245          */
 246         if (sock->sk->sk_family == AF_INET6)
 247                 udp_encap_enable();
 248
 249         rcu_assign_pointer(bareudp->sock, sock);
 250         return 0;
 251 }
 252
 253 static int bareudp_open(struct net_device *dev)
 254 {
 255         struct bareudp_dev *bareudp = netdev_priv(dev);
 256         int ret = 0;
 257
 258         ret =  bareudp_socket_create(bareudp, bareudp->port);
 259         return ret;
 260 }
 261
 262 static void bareudp_sock_release(struct bareudp_dev *bareudp)
 263 {
 264         struct socket *sock;
 265
 266         sock = bareudp->sock;
 267         rcu_assign_pointer(bareudp->sock, NULL);
 268         synchronize_net();
 269         udp_tunnel_sock_release(sock);
 270 }
 271
 272 static int bareudp_stop(struct net_device *dev)
 273 {
 274         struct bareudp_dev *bareudp = netdev_priv(dev);
 275
 276         bareudp_sock_release(bareudp);
 277         return 0;
 278 }
 279
 280 static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 281                             struct bareudp_dev *bareudp,
 282                             const struct ip_tunnel_info *info)
 283 {
 284         bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
 285         bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
 286         struct socket *sock = rcu_dereference(bareudp->sock);
 287         bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
 288         const struct ip_tunnel_key *key = &info->key;
 289         struct rtable *rt;
 290         __be16 sport, df;
 291         int min_headroom;
 292         __u8 tos, ttl;
 293         __be32 saddr;
 294         int err;
 295
 296         if (!sock)
 297                 return -ESHUTDOWN;
 298
 299         rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr, info,
 300                                     IPPROTO_UDP, use_cache);
 301
 302         if (IS_ERR(rt))
 303                 return PTR_ERR(rt);
 304
 305         skb_tunnel_check_pmtu(skb, &rt->dst,
 306                               BAREUDP_IPV4_HLEN + info->options_len, false);
 307
 308         sport = udp_flow_src_port(bareudp->net, skb,
 309                                   bareudp->sport_min, USHRT_MAX,
 310                                   true);
 311         tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
 312         ttl = key->ttl;
 313         df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
 314         skb_scrub_packet(skb, xnet);
 315
 316         err = -ENOSPC;
 317         if (!skb_pull(skb, skb_network_offset(skb)))
 318                 goto free_dst;
 319
 320         min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len +
 321                 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
 322
 323         err = skb_cow_head(skb, min_headroom);
 324         if (unlikely(err))
 325                 goto free_dst;
 326
 327         err = udp_tunnel_handle_offloads(skb, udp_sum);
 328         if (err)
 329                 goto free_dst;
 330
 331         skb_set_inner_protocol(skb, bareudp->ethertype);
 332         udp_tunnel_xmit_skb(rt, sock->sk, skb, saddr, info->key.u.ipv4.dst,
 333                             tos, ttl, df, sport, bareudp->port,
 334                             !net_eq(bareudp->net, dev_net(bareudp->dev)),
 335                             !(info->key.tun_flags & TUNNEL_CSUM));
 336         return 0;
 337
 338 free_dst:
 339         dst_release(&rt->dst);
 340         return err;
 341 }
 342
 343 static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 344                              struct bareudp_dev *bareudp,
 345                              const struct ip_tunnel_info *info)
 346 {
 347         bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
 348         bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
 349         struct socket *sock  = rcu_dereference(bareudp->sock);
 350         bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
 351         const struct ip_tunnel_key *key = &info->key;
 352         struct dst_entry *dst = NULL;
 353         struct in6_addr saddr, daddr;
 354         int min_headroom;
 355         __u8 prio, ttl;
 356         __be16 sport;
 357         int err;
 358
 359         if (!sock)
 360                 return -ESHUTDOWN;
 361
 362         dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock, &saddr, info,
 363                                     IPPROTO_UDP, use_cache);
 364         if (IS_ERR(dst))
 365                 return PTR_ERR(dst);
 366
 367         skb_tunnel_check_pmtu(skb, dst, BAREUDP_IPV6_HLEN + info->options_len,
 368                               false);
 369
 370         sport = udp_flow_src_port(bareudp->net, skb,
 371                                   bareudp->sport_min, USHRT_MAX,
 372                                   true);
 373         prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
 374         ttl = key->ttl;
 375
 376         skb_scrub_packet(skb, xnet);
 377
 378         err = -ENOSPC;
 379         if (!skb_pull(skb, skb_network_offset(skb)))
 380                 goto free_dst;
 381
 382         min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len +
 383                 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
 384
 385         err = skb_cow_head(skb, min_headroom);
 386         if (unlikely(err))
 387                 goto free_dst;
 388
 389         err = udp_tunnel_handle_offloads(skb, udp_sum);
 390         if (err)
 391                 goto free_dst;
 392
 393         daddr = info->key.u.ipv6.dst;
 394         udp_tunnel6_xmit_skb(dst, sock->sk, skb, dev,
 395                              &saddr, &daddr, prio, ttl,
 396                              info->key.label, sport, bareudp->port,
 397                              !(info->key.tun_flags & TUNNEL_CSUM));
 398         return 0;
 399
 400 free_dst:
 401         dst_release(dst);
 402         return err;
 403 }
 404
 405 static bool bareudp_proto_valid(struct bareudp_dev *bareudp, __be16 proto)
 406 {
 407         if (bareudp->ethertype == proto)
 408                 return true;
 409
 410         if (!bareudp->multi_proto_mode)
 411                 return false;
 412
 413         if (bareudp->ethertype == htons(ETH_P_MPLS_UC) &&
 414             proto == htons(ETH_P_MPLS_MC))
 415                 return true;
 416
 417         if (bareudp->ethertype == htons(ETH_P_IP) &&
 418             proto == htons(ETH_P_IPV6))
 419                 return true;
 420
 421         return false;
 422 }
 423
 424 static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
 425 {
 426         struct bareudp_dev *bareudp = netdev_priv(dev);
 427         struct ip_tunnel_info *info = NULL;
 428         int err;
 429
 430         if (!bareudp_proto_valid(bareudp, skb->protocol)) {
 431                 err = -EINVAL;
 432                 goto tx_error;
 433         }
 434
 435         info = skb_tunnel_info(skb);
 436         if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
 437                 err = -EINVAL;
 438                 goto tx_error;
 439         }
 440
 441         rcu_read_lock();
 442         if (IS_ENABLED(CONFIG_IPV6) && info->mode & IP_TUNNEL_INFO_IPV6)
 443                 err = bareudp6_xmit_skb(skb, dev, bareudp, info);
 444         else
 445                 err = bareudp_xmit_skb(skb, dev, bareudp, info);
 446
 447         rcu_read_unlock();
 448
 449         if (likely(!err))
 450                 return NETDEV_TX_OK;
 451 tx_error:
 452         dev_kfree_skb(skb);
 453
 454         if (err == -ELOOP)
 455                 dev->stats.collisions++;
 456         else if (err == -ENETUNREACH)
 457                 dev->stats.tx_carrier_errors++;
 458
 459         dev->stats.tx_errors++;
 460         return NETDEV_TX_OK;
 461 }
 462
 463 static int bareudp_fill_metadata_dst(struct net_device *dev,
 464                                      struct sk_buff *skb)
 465 {
 466         struct ip_tunnel_info *info = skb_tunnel_info(skb);
 467         struct bareudp_dev *bareudp = netdev_priv(dev);
 468         bool use_cache;
 469
 470         use_cache = ip_tunnel_dst_cache_usable(skb, info);
 471
 472         if (!IS_ENABLED(CONFIG_IPV6) || ip_tunnel_info_af(info) == AF_INET) {
 473                 struct rtable *rt;
 474                 __be32 saddr;
 475
 476                 rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr,
 477                                             info, IPPROTO_UDP, use_cache);
 478                 if (IS_ERR(rt))
 479                         return PTR_ERR(rt);
 480
 481                 ip_rt_put(rt);
 482                 info->key.u.ipv4.src = saddr;
 483         } else if (ip_tunnel_info_af(info) == AF_INET6) {
 484                 struct dst_entry *dst;
 485                 struct in6_addr saddr;
 486                 struct socket *sock = rcu_dereference(bareudp->sock);
 487
 488                 dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock,
 489                                             &saddr, info, IPPROTO_UDP,
 490                                             use_cache);
 491                 if (IS_ERR(dst))
 492                         return PTR_ERR(dst);
 493
 494                 dst_release(dst);
 495                 info->key.u.ipv6.src = saddr;
 496         } else {
 497                 return -EINVAL;
 498         }
 499
 500         info->key.tp_src = udp_flow_src_port(bareudp->net, skb,
 501                                              bareudp->sport_min,
 502                         USHRT_MAX, true);
 503         info->key.tp_dst = bareudp->port;
 504         return 0;
 505 }
 506
 507 static const struct net_device_ops bareudp_netdev_ops = {
 508         .ndo_init               = bareudp_init,
 509         .ndo_uninit             = bareudp_uninit,
 510         .ndo_open               = bareudp_open,
 511         .ndo_stop               = bareudp_stop,
 512         .ndo_start_xmit         = bareudp_xmit,
 513         .ndo_get_stats64        = dev_get_tstats64,
 514         .ndo_fill_metadata_dst  = bareudp_fill_metadata_dst,
 515 };
 516
 517 static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
 518         [IFLA_BAREUDP_PORT]                = { .type = NLA_U16 },
 519         [IFLA_BAREUDP_ETHERTYPE]           = { .type = NLA_U16 },
 520         [IFLA_BAREUDP_SRCPORT_MIN]         = { .type = NLA_U16 },
 521         [IFLA_BAREUDP_MULTIPROTO_MODE]     = { .type = NLA_FLAG },
 522 };
 523
 524 /* Info for udev, that this is a virtual tunnel endpoint */
 525 static const struct device_type bareudp_type = {
 526         .name = "bareudp",
 527 };
 528
 529 /* Initialize the device structure. */
 530 static void bareudp_setup(struct net_device *dev)
 531 {
 532         dev->netdev_ops = &bareudp_netdev_ops;
 533         dev->needs_free_netdev = true;
 534         SET_NETDEV_DEVTYPE(dev, &bareudp_type);
 535         dev->features    |= NETIF_F_SG | NETIF_F_HW_CSUM;
 536         dev->features    |= NETIF_F_RXCSUM;
 537         dev->features    |= NETIF_F_GSO_SOFTWARE;
 538         dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
 539         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
 540         dev->hard_header_len = 0;
 541         dev->addr_len = 0;
 542         dev->mtu = ETH_DATA_LEN;
 543         dev->min_mtu = IPV4_MIN_MTU;
 544         dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
 545         dev->type = ARPHRD_NONE;
 546         netif_keep_dst(dev);
 547         dev->priv_flags |= IFF_NO_QUEUE;
 548         dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 549 }
 550
 551 static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
 552                             struct netlink_ext_ack *extack)
 553 {
 554         if (!data) {
 555                 NL_SET_ERR_MSG(extack,
 556                                "Not enough attributes provided to perform the operation");
 557                 return -EINVAL;
 558         }
 559         return 0;
 560 }
 561
 562 static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf,
 563                         struct netlink_ext_ack *extack)
 564 {
 565         memset(conf, 0, sizeof(*conf));
 566
 567         if (!data[IFLA_BAREUDP_PORT]) {
 568                 NL_SET_ERR_MSG(extack, "port not specified");
 569                 return -EINVAL;
 570         }
 571         if (!data[IFLA_BAREUDP_ETHERTYPE]) {
 572                 NL_SET_ERR_MSG(extack, "ethertype not specified");
 573                 return -EINVAL;
 574         }
 575
 576         if (data[IFLA_BAREUDP_PORT])
 577                 conf->port =  nla_get_u16(data[IFLA_BAREUDP_PORT]);
 578
 579         if (data[IFLA_BAREUDP_ETHERTYPE])
 580                 conf->ethertype =  nla_get_u16(data[IFLA_BAREUDP_ETHERTYPE]);
 581
 582         if (data[IFLA_BAREUDP_SRCPORT_MIN])
 583                 conf->sport_min =  nla_get_u16(data[IFLA_BAREUDP_SRCPORT_MIN]);
 584
 585         if (data[IFLA_BAREUDP_MULTIPROTO_MODE])
 586                 conf->multi_proto_mode = true;
 587
 588         return 0;
 589 }
 590
 591 static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
 592                                             const struct bareudp_conf *conf)
 593 {
 594         struct bareudp_dev *bareudp, *t = NULL;
 595
 596         list_for_each_entry(bareudp, &bn->bareudp_list, next) {
 597                 if (conf->port == bareudp->port)
 598                         t = bareudp;
 599         }
 600         return t;
 601 }
 602
 603 static int bareudp_configure(struct net *net, struct net_device *dev,
 604                              struct bareudp_conf *conf)
 605 {
 606         struct bareudp_net *bn = net_generic(net, bareudp_net_id);
 607         struct bareudp_dev *t, *bareudp = netdev_priv(dev);
 608         int err;
 609
 610         bareudp->net = net;
 611         bareudp->dev = dev;
 612         t = bareudp_find_dev(bn, conf);
 613         if (t)
 614                 return -EBUSY;
 615
 616         if (conf->multi_proto_mode &&
 617             (conf->ethertype != htons(ETH_P_MPLS_UC) &&
 618              conf->ethertype != htons(ETH_P_IP)))
 619                 return -EINVAL;
 620
 621         bareudp->port = conf->port;
 622         bareudp->ethertype = conf->ethertype;
 623         bareudp->sport_min = conf->sport_min;
 624         bareudp->multi_proto_mode = conf->multi_proto_mode;
 625
 626         err = register_netdevice(dev);
 627         if (err)
 628                 return err;
 629
 630         list_add(&bareudp->next, &bn->bareudp_list);
 631         return 0;
 632 }
 633
 634 static int bareudp_link_config(struct net_device *dev,
 635                                struct nlattr *tb[])
 636 {
 637         int err;
 638
 639         if (tb[IFLA_MTU]) {
 640                 err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
 641                 if (err)
 642                         return err;
 643         }
 644         return 0;
 645 }
 646
 647 static int bareudp_newlink(struct net *net, struct net_device *dev,
 648                            struct nlattr *tb[], struct nlattr *data[],
 649                            struct netlink_ext_ack *extack)
 650 {
 651         struct bareudp_conf conf;
 652         int err;
 653
 654         err = bareudp2info(data, &conf, extack);
 655         if (err)
 656                 return err;
 657
 658         err = bareudp_configure(net, dev, &conf);
 659         if (err)
 660                 return err;
 661
 662         err = bareudp_link_config(dev, tb);
 663         if (err)
 664                 return err;
 665
 666         return 0;
 667 }
 668
 669 static void bareudp_dellink(struct net_device *dev, struct list_head *head)
 670 {
 671         struct bareudp_dev *bareudp = netdev_priv(dev);
 672
 673         list_del(&bareudp->next);
 674         unregister_netdevice_queue(dev, head);
 675 }
 676
 677 static size_t bareudp_get_size(const struct net_device *dev)
 678 {
 679         return  nla_total_size(sizeof(__be16)) +  /* IFLA_BAREUDP_PORT */
 680                 nla_total_size(sizeof(__be16)) +  /* IFLA_BAREUDP_ETHERTYPE */
 681                 nla_total_size(sizeof(__u16))  +  /* IFLA_BAREUDP_SRCPORT_MIN */
 682                 nla_total_size(0)              +  /* IFLA_BAREUDP_MULTIPROTO_MODE */
 683                 0;
 684 }
 685
 686 static int bareudp_fill_info(struct sk_buff *skb, const struct net_device *dev)
 687 {
 688         struct bareudp_dev *bareudp = netdev_priv(dev);
 689
 690         if (nla_put_be16(skb, IFLA_BAREUDP_PORT, bareudp->port))
 691                 goto nla_put_failure;
 692         if (nla_put_be16(skb, IFLA_BAREUDP_ETHERTYPE, bareudp->ethertype))
 693                 goto nla_put_failure;
 694         if (nla_put_u16(skb, IFLA_BAREUDP_SRCPORT_MIN, bareudp->sport_min))
 695                 goto nla_put_failure;
 696         if (bareudp->multi_proto_mode &&
 697             nla_put_flag(skb, IFLA_BAREUDP_MULTIPROTO_MODE))
 698                 goto nla_put_failure;
 699
 700         return 0;
 701
 702 nla_put_failure:
 703         return -EMSGSIZE;
 704 }
 705
 706 static struct rtnl_link_ops bareudp_link_ops __read_mostly = {
 707         .kind           = "bareudp",
 708         .maxtype        = IFLA_BAREUDP_MAX,
 709         .policy         = bareudp_policy,
 710         .priv_size      = sizeof(struct bareudp_dev),
 711         .setup          = bareudp_setup,
 712         .validate       = bareudp_validate,
 713         .newlink        = bareudp_newlink,
 714         .dellink        = bareudp_dellink,
 715         .get_size       = bareudp_get_size,
 716         .fill_info      = bareudp_fill_info,
 717 };
 718
 719 struct net_device *bareudp_dev_create(struct net *net, const char *name,
 720                                       u8 name_assign_type,
 721                                       struct bareudp_conf *conf)
 722 {
 723         struct nlattr *tb[IFLA_MAX + 1];
 724         struct net_device *dev;
 725         LIST_HEAD(list_kill);
 726         int err;
 727
 728         memset(tb, 0, sizeof(tb));
 729         dev = rtnl_create_link(net, name, name_assign_type,
 730                                &bareudp_link_ops, tb, NULL);
 731         if (IS_ERR(dev))
 732                 return dev;
 733
 734         err = bareudp_configure(net, dev, conf);
 735         if (err) {
 736                 free_netdev(dev);
 737                 return ERR_PTR(err);
 738         }
 739         err = dev_set_mtu(dev, IP_MAX_MTU - BAREUDP_BASE_HLEN);
 740         if (err)
 741                 goto err;
 742
 743         err = rtnl_configure_link(dev, NULL);
 744         if (err < 0)
 745                 goto err;
 746
 747         return dev;
 748 err:
 749         bareudp_dellink(dev, &list_kill);
 750         unregister_netdevice_many(&list_kill);
 751         return ERR_PTR(err);
 752 }
 753 EXPORT_SYMBOL_GPL(bareudp_dev_create);
 754
 755 static __net_init int bareudp_init_net(struct net *net)
 756 {
 757         struct bareudp_net *bn = net_generic(net, bareudp_net_id);
 758
 759         INIT_LIST_HEAD(&bn->bareudp_list);
 760         return 0;
 761 }
 762
 763 static void bareudp_destroy_tunnels(struct net *net, struct list_head *head)
 764 {
 765         struct bareudp_net *bn = net_generic(net, bareudp_net_id);
 766         struct bareudp_dev *bareudp, *next;
 767
 768         list_for_each_entry_safe(bareudp, next, &bn->bareudp_list, next)
 769                 unregister_netdevice_queue(bareudp->dev, head);
 770 }
 771
 772 static void __net_exit bareudp_exit_batch_net(struct list_head *net_list)
 773 {
 774         struct net *net;
 775         LIST_HEAD(list);
 776
 777         rtnl_lock();
 778         list_for_each_entry(net, net_list, exit_list)
 779                 bareudp_destroy_tunnels(net, &list);
 780
 781         /* unregister the devices gathered above */
 782         unregister_netdevice_many(&list);
 783         rtnl_unlock();
 784 }
 785
 786 static struct pernet_operations bareudp_net_ops = {
 787         .init = bareudp_init_net,
 788         .exit_batch = bareudp_exit_batch_net,
 789         .id   = &bareudp_net_id,
 790         .size = sizeof(struct bareudp_net),
 791 };
 792
 793 static int __init bareudp_init_module(void)
 794 {
 795         int rc;
 796
 797         rc = register_pernet_subsys(&bareudp_net_ops);
 798         if (rc)
 799                 goto out1;
 800
 801         rc = rtnl_link_register(&bareudp_link_ops);
 802         if (rc)
 803                 goto out2;
 804
 805         return 0;
 806 out2:
 807         unregister_pernet_subsys(&bareudp_net_ops);
 808 out1:
 809         return rc;
 810 }
 811 late_initcall(bareudp_init_module);
 812
 813 static void __exit bareudp_cleanup_module(void)
 814 {
 815         rtnl_link_unregister(&bareudp_link_ops);
 816         unregister_pernet_subsys(&bareudp_net_ops);
 817 }
 818 module_exit(bareudp_cleanup_module);
 819
 820 MODULE_ALIAS_RTNL_LINK("bareudp");
 821 MODULE_LICENSE("GPL");
 822 MODULE_AUTHOR("Martin Varghese <martin.varghese@nokia.com>");
 823 MODULE_DESCRIPTION("Interface driver for UDP encapsulated traffic");