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                 __u8 ipversion;
  75
  76                 if (skb_copy_bits(skb, BAREUDP_BASE_HLEN, &ipversion,
  77                                   sizeof(ipversion))) {
  78                         bareudp->dev->stats.rx_dropped++;
  79                         goto drop;
  80                 }
  81                 ipversion >>= 4;
  82
  83                 if (ipversion == 4) {
  84                         proto = htons(ETH_P_IP);
  85                 } else if (ipversion == 6 && bareudp->multi_proto_mode) {
  86                         proto = htons(ETH_P_IPV6);
  87                 } else {
  88                         bareudp->dev->stats.rx_dropped++;
  89                         goto drop;
  90                 }
  91         } else if (bareudp->ethertype == htons(ETH_P_MPLS_UC)) {
  92                 struct iphdr *tunnel_hdr;
  93
  94                 tunnel_hdr = (struct iphdr *)skb_network_header(skb);
  95                 if (tunnel_hdr->version == 4) {
  96                         if (!ipv4_is_multicast(tunnel_hdr->daddr)) {
  97                                 proto = bareudp->ethertype;
  98                         } else if (bareudp->multi_proto_mode &&
  99                                    ipv4_is_multicast(tunnel_hdr->daddr)) {
 100                                 proto = htons(ETH_P_MPLS_MC);
 101                         } else {
 102                                 bareudp->dev->stats.rx_dropped++;
 103                                 goto drop;
 104                         }
 105                 } else {
 106                         int addr_type;
 107                         struct ipv6hdr *tunnel_hdr_v6;
 108
 109                         tunnel_hdr_v6 = (struct ipv6hdr *)skb_network_header(skb);
 110                         addr_type =
 111                         ipv6_addr_type((struct in6_addr *)&tunnel_hdr_v6->daddr);
 112                         if (!(addr_type & IPV6_ADDR_MULTICAST)) {
 113                                 proto = bareudp->ethertype;
 114                         } else if (bareudp->multi_proto_mode &&
 115                                    (addr_type & IPV6_ADDR_MULTICAST)) {
 116                                 proto = htons(ETH_P_MPLS_MC);
 117                         } else {
 118                                 bareudp->dev->stats.rx_dropped++;
 119                                 goto drop;
 120                         }
 121                 }
 122         } else {
 123                 proto = bareudp->ethertype;
 124         }
 125
 126         if (iptunnel_pull_header(skb, BAREUDP_BASE_HLEN,
 127                                  proto,
 128                                  !net_eq(bareudp->net,
 129                                  dev_net(bareudp->dev)))) {
 130                 bareudp->dev->stats.rx_dropped++;
 131                 goto drop;
 132         }
 133         tun_dst = udp_tun_rx_dst(skb, family, TUNNEL_KEY, 0, 0);
 134         if (!tun_dst) {
 135                 bareudp->dev->stats.rx_dropped++;
 136                 goto drop;
 137         }
 138         skb_dst_set(skb, &tun_dst->dst);
 139         skb->dev = bareudp->dev;
 140         oiph = skb_network_header(skb);
 141         skb_reset_network_header(skb);
 142
 143         if (!ipv6_mod_enabled() || family == AF_INET)
 144                 err = IP_ECN_decapsulate(oiph, skb);
 145         else
 146                 err = IP6_ECN_decapsulate(oiph, skb);
 147
 148         if (unlikely(err)) {
 149                 if (log_ecn_error) {
 150                         if  (!ipv6_mod_enabled() || family == AF_INET)
 151                                 net_info_ratelimited("non-ECT from %pI4 "
 152                                                      "with TOS=%#x\n",
 153                                                      &((struct iphdr *)oiph)->saddr,
 154                                                      ((struct iphdr *)oiph)->tos);
 155                         else
 156                                 net_info_ratelimited("non-ECT from %pI6\n",
 157                                                      &((struct ipv6hdr *)oiph)->saddr);
 158                 }
 159                 if (err > 1) {
 160                         ++bareudp->dev->stats.rx_frame_errors;
 161                         ++bareudp->dev->stats.rx_errors;
 162                         goto drop;
 163                 }
 164         }
 165
 166         len = skb->len;
 167         err = gro_cells_receive(&bareudp->gro_cells, skb);
 168         if (likely(err == NET_RX_SUCCESS))
 169                 dev_sw_netstats_rx_add(bareudp->dev, len);
 170
 171         return 0;
 172 drop:
 173         /* Consume bad packet */
 174         kfree_skb(skb);
 175
 176         return 0;
 177 }
 178
 179 static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
 180 {
 181         return 0;
 182 }
 183
 184 static int bareudp_init(struct net_device *dev)
 185 {
 186         struct bareudp_dev *bareudp = netdev_priv(dev);
 187         int err;
 188
 189         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 190         if (!dev->tstats)
 191                 return -ENOMEM;
 192
 193         err = gro_cells_init(&bareudp->gro_cells, dev);
 194         if (err) {
 195                 free_percpu(dev->tstats);
 196                 return err;
 197         }
 198         return 0;
 199 }
 200
 201 static void bareudp_uninit(struct net_device *dev)
 202 {
 203         struct bareudp_dev *bareudp = netdev_priv(dev);
 204
 205         gro_cells_destroy(&bareudp->gro_cells);
 206         free_percpu(dev->tstats);
 207 }
 208
 209 static struct socket *bareudp_create_sock(struct net *net, __be16 port)
 210 {
 211         struct udp_port_cfg udp_conf;
 212         struct socket *sock;
 213         int err;
 214
 215         memset(&udp_conf, 0, sizeof(udp_conf));
 216
 217         if (ipv6_mod_enabled())
 218                 udp_conf.family = AF_INET6;
 219         else
 220                 udp_conf.family = AF_INET;
 221
 222         udp_conf.local_udp_port = port;
 223         /* Open UDP socket */
 224         err = udp_sock_create(net, &udp_conf, &sock);
 225         if (err < 0)
 226                 return ERR_PTR(err);
 227
 228         return sock;
 229 }
 230
 231 /* Create new listen socket if needed */
 232 static int bareudp_socket_create(struct bareudp_dev *bareudp, __be16 port)
 233 {
 234         struct udp_tunnel_sock_cfg tunnel_cfg;
 235         struct socket *sock;
 236
 237         sock = bareudp_create_sock(bareudp->net, port);
 238         if (IS_ERR(sock))
 239                 return PTR_ERR(sock);
 240
 241         /* Mark socket as an encapsulation socket */
 242         memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
 243         tunnel_cfg.sk_user_data = bareudp;
 244         tunnel_cfg.encap_type = 1;
 245         tunnel_cfg.encap_rcv = bareudp_udp_encap_recv;
 246         tunnel_cfg.encap_err_lookup = bareudp_err_lookup;
 247         tunnel_cfg.encap_destroy = NULL;
 248         setup_udp_tunnel_sock(bareudp->net, sock, &tunnel_cfg);
 249
 250         rcu_assign_pointer(bareudp->sock, sock);
 251         return 0;
 252 }
 253
 254 static int bareudp_open(struct net_device *dev)
 255 {
 256         struct bareudp_dev *bareudp = netdev_priv(dev);
 257         int ret = 0;
 258
 259         ret =  bareudp_socket_create(bareudp, bareudp->port);
 260         return ret;
 261 }
 262
 263 static void bareudp_sock_release(struct bareudp_dev *bareudp)
 264 {
 265         struct socket *sock;
 266
 267         sock = bareudp->sock;
 268         rcu_assign_pointer(bareudp->sock, NULL);
 269         synchronize_net();
 270         udp_tunnel_sock_release(sock);
 271 }
 272
 273 static int bareudp_stop(struct net_device *dev)
 274 {
 275         struct bareudp_dev *bareudp = netdev_priv(dev);
 276
 277         bareudp_sock_release(bareudp);
 278         return 0;
 279 }
 280
 281 static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 282                             struct bareudp_dev *bareudp,
 283                             const struct ip_tunnel_info *info)
 284 {
 285         bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
 286         bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
 287         struct socket *sock = rcu_dereference(bareudp->sock);
 288         bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
 289         const struct ip_tunnel_key *key = &info->key;
 290         struct rtable *rt;
 291         __be16 sport, df;
 292         int min_headroom;
 293         __u8 tos, ttl;
 294         __be32 saddr;
 295         int err;
 296
 297         if (!sock)
 298                 return -ESHUTDOWN;
 299
 300         rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr, info,
 301                                     IPPROTO_UDP, use_cache);
 302
 303         if (IS_ERR(rt))
 304                 return PTR_ERR(rt);
 305
 306         skb_tunnel_check_pmtu(skb, &rt->dst,
 307                               BAREUDP_IPV4_HLEN + info->options_len, false);
 308
 309         sport = udp_flow_src_port(bareudp->net, skb,
 310                                   bareudp->sport_min, USHRT_MAX,
 311                                   true);
 312         tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
 313         ttl = key->ttl;
 314         df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
 315         skb_scrub_packet(skb, xnet);
 316
 317         err = -ENOSPC;
 318         if (!skb_pull(skb, skb_network_offset(skb)))
 319                 goto free_dst;
 320
 321         min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len +
 322                 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
 323
 324         err = skb_cow_head(skb, min_headroom);
 325         if (unlikely(err))
 326                 goto free_dst;
 327
 328         err = udp_tunnel_handle_offloads(skb, udp_sum);
 329         if (err)
 330                 goto free_dst;
 331
 332         skb_set_inner_protocol(skb, bareudp->ethertype);
 333         udp_tunnel_xmit_skb(rt, sock->sk, skb, saddr, info->key.u.ipv4.dst,
 334                             tos, ttl, df, sport, bareudp->port,
 335                             !net_eq(bareudp->net, dev_net(bareudp->dev)),
 336                             !(info->key.tun_flags & TUNNEL_CSUM));
 337         return 0;
 338
 339 free_dst:
 340         dst_release(&rt->dst);
 341         return err;
 342 }
 343
 344 static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 345                              struct bareudp_dev *bareudp,
 346                              const struct ip_tunnel_info *info)
 347 {
 348         bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
 349         bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
 350         struct socket *sock  = rcu_dereference(bareudp->sock);
 351         bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
 352         const struct ip_tunnel_key *key = &info->key;
 353         struct dst_entry *dst = NULL;
 354         struct in6_addr saddr, daddr;
 355         int min_headroom;
 356         __u8 prio, ttl;
 357         __be16 sport;
 358         int err;
 359
 360         if (!sock)
 361                 return -ESHUTDOWN;
 362
 363         dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock, &saddr, info,
 364                                     IPPROTO_UDP, use_cache);
 365         if (IS_ERR(dst))
 366                 return PTR_ERR(dst);
 367
 368         skb_tunnel_check_pmtu(skb, dst, BAREUDP_IPV6_HLEN + info->options_len,
 369                               false);
 370
 371         sport = udp_flow_src_port(bareudp->net, skb,
 372                                   bareudp->sport_min, USHRT_MAX,
 373                                   true);
 374         prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
 375         ttl = key->ttl;
 376
 377         skb_scrub_packet(skb, xnet);
 378
 379         err = -ENOSPC;
 380         if (!skb_pull(skb, skb_network_offset(skb)))
 381                 goto free_dst;
 382
 383         min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len +
 384                 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct ipv6hdr);
 385
 386         err = skb_cow_head(skb, min_headroom);
 387         if (unlikely(err))
 388                 goto free_dst;
 389
 390         err = udp_tunnel_handle_offloads(skb, udp_sum);
 391         if (err)
 392                 goto free_dst;
 393
 394         daddr = info->key.u.ipv6.dst;
 395         udp_tunnel6_xmit_skb(dst, sock->sk, skb, dev,
 396                              &saddr, &daddr, prio, ttl,
 397                              info->key.label, sport, bareudp->port,
 398                              !(info->key.tun_flags & TUNNEL_CSUM));
 399         return 0;
 400
 401 free_dst:
 402         dst_release(dst);
 403         return err;
 404 }
 405
 406 static bool bareudp_proto_valid(struct bareudp_dev *bareudp, __be16 proto)
 407 {
 408         if (bareudp->ethertype == proto)
 409                 return true;
 410
 411         if (!bareudp->multi_proto_mode)
 412                 return false;
 413
 414         if (bareudp->ethertype == htons(ETH_P_MPLS_UC) &&
 415             proto == htons(ETH_P_MPLS_MC))
 416                 return true;
 417
 418         if (bareudp->ethertype == htons(ETH_P_IP) &&
 419             proto == htons(ETH_P_IPV6))
 420                 return true;
 421
 422         return false;
 423 }
 424
 425 static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
 426 {
 427         struct bareudp_dev *bareudp = netdev_priv(dev);
 428         struct ip_tunnel_info *info = NULL;
 429         int err;
 430
 431         if (!bareudp_proto_valid(bareudp, skb->protocol)) {
 432                 err = -EINVAL;
 433                 goto tx_error;
 434         }
 435
 436         info = skb_tunnel_info(skb);
 437         if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
 438                 err = -EINVAL;
 439                 goto tx_error;
 440         }
 441
 442         rcu_read_lock();
 443         if (ipv6_mod_enabled() && info->mode & IP_TUNNEL_INFO_IPV6)
 444                 err = bareudp6_xmit_skb(skb, dev, bareudp, info);
 445         else
 446                 err = bareudp_xmit_skb(skb, dev, bareudp, info);
 447
 448         rcu_read_unlock();
 449
 450         if (likely(!err))
 451                 return NETDEV_TX_OK;
 452 tx_error:
 453         dev_kfree_skb(skb);
 454
 455         if (err == -ELOOP)
 456                 dev->stats.collisions++;
 457         else if (err == -ENETUNREACH)
 458                 dev->stats.tx_carrier_errors++;
 459
 460         dev->stats.tx_errors++;
 461         return NETDEV_TX_OK;
 462 }
 463
 464 static int bareudp_fill_metadata_dst(struct net_device *dev,
 465                                      struct sk_buff *skb)
 466 {
 467         struct ip_tunnel_info *info = skb_tunnel_info(skb);
 468         struct bareudp_dev *bareudp = netdev_priv(dev);
 469         bool use_cache;
 470
 471         use_cache = ip_tunnel_dst_cache_usable(skb, info);
 472
 473         if (!ipv6_mod_enabled() || ip_tunnel_info_af(info) == AF_INET) {
 474                 struct rtable *rt;
 475                 __be32 saddr;
 476
 477                 rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr,
 478                                             info, IPPROTO_UDP, use_cache);
 479                 if (IS_ERR(rt))
 480                         return PTR_ERR(rt);
 481
 482                 ip_rt_put(rt);
 483                 info->key.u.ipv4.src = saddr;
 484         } else if (ip_tunnel_info_af(info) == AF_INET6) {
 485                 struct dst_entry *dst;
 486                 struct in6_addr saddr;
 487                 struct socket *sock = rcu_dereference(bareudp->sock);
 488
 489                 dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock,
 490                                             &saddr, info, IPPROTO_UDP,
 491                                             use_cache);
 492                 if (IS_ERR(dst))
 493                         return PTR_ERR(dst);
 494
 495                 dst_release(dst);
 496                 info->key.u.ipv6.src = saddr;
 497         } else {
 498                 return -EINVAL;
 499         }
 500
 501         info->key.tp_src = udp_flow_src_port(bareudp->net, skb,
 502                                              bareudp->sport_min,
 503                         USHRT_MAX, true);
 504         info->key.tp_dst = bareudp->port;
 505         return 0;
 506 }
 507
 508 static const struct net_device_ops bareudp_netdev_ops = {
 509         .ndo_init               = bareudp_init,
 510         .ndo_uninit             = bareudp_uninit,
 511         .ndo_open               = bareudp_open,
 512         .ndo_stop               = bareudp_stop,
 513         .ndo_start_xmit         = bareudp_xmit,
 514         .ndo_get_stats64        = ip_tunnel_get_stats64,
 515         .ndo_fill_metadata_dst  = bareudp_fill_metadata_dst,
 516 };
 517
 518 static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
 519         [IFLA_BAREUDP_PORT]                = { .type = NLA_U16 },
 520         [IFLA_BAREUDP_ETHERTYPE]           = { .type = NLA_U16 },
 521         [IFLA_BAREUDP_SRCPORT_MIN]         = { .type = NLA_U16 },
 522         [IFLA_BAREUDP_MULTIPROTO_MODE]     = { .type = NLA_FLAG },
 523 };
 524
 525 /* Info for udev, that this is a virtual tunnel endpoint */
 526 static struct device_type bareudp_type = {
 527         .name = "bareudp",
 528 };
 529
 530 /* Initialize the device structure. */
 531 static void bareudp_setup(struct net_device *dev)
 532 {
 533         dev->netdev_ops = &bareudp_netdev_ops;
 534         dev->needs_free_netdev = true;
 535         SET_NETDEV_DEVTYPE(dev, &bareudp_type);
 536         dev->features    |= NETIF_F_SG | NETIF_F_HW_CSUM;
 537         dev->features    |= NETIF_F_RXCSUM;
 538         dev->features    |= NETIF_F_LLTX;
 539         dev->features    |= NETIF_F_GSO_SOFTWARE;
 540         dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_RXCSUM;
 541         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
 542         dev->hard_header_len = 0;
 543         dev->addr_len = 0;
 544         dev->mtu = ETH_DATA_LEN;
 545         dev->min_mtu = IPV4_MIN_MTU;
 546         dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
 547         dev->type = ARPHRD_NONE;
 548         netif_keep_dst(dev);
 549         dev->priv_flags |= IFF_NO_QUEUE;
 550         dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 551 }
 552
 553 static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
 554                             struct netlink_ext_ack *extack)
 555 {
 556         if (!data) {
 557                 NL_SET_ERR_MSG(extack,
 558                                "Not enough attributes provided to perform the operation");
 559                 return -EINVAL;
 560         }
 561         return 0;
 562 }
 563
 564 static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf,
 565                         struct netlink_ext_ack *extack)
 566 {
 567         memset(conf, 0, sizeof(*conf));
 568
 569         if (!data[IFLA_BAREUDP_PORT]) {
 570                 NL_SET_ERR_MSG(extack, "port not specified");
 571                 return -EINVAL;
 572         }
 573         if (!data[IFLA_BAREUDP_ETHERTYPE]) {
 574                 NL_SET_ERR_MSG(extack, "ethertype not specified");
 575                 return -EINVAL;
 576         }
 577
 578         if (data[IFLA_BAREUDP_PORT])
 579                 conf->port =  nla_get_u16(data[IFLA_BAREUDP_PORT]);
 580
 581         if (data[IFLA_BAREUDP_ETHERTYPE])
 582                 conf->ethertype =  nla_get_u16(data[IFLA_BAREUDP_ETHERTYPE]);
 583
 584         if (data[IFLA_BAREUDP_SRCPORT_MIN])
 585                 conf->sport_min =  nla_get_u16(data[IFLA_BAREUDP_SRCPORT_MIN]);
 586
 587         if (data[IFLA_BAREUDP_MULTIPROTO_MODE])
 588                 conf->multi_proto_mode = true;
 589
 590         return 0;
 591 }
 592
 593 static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
 594                                             const struct bareudp_conf *conf)
 595 {
 596         struct bareudp_dev *bareudp, *t = NULL;
 597
 598         list_for_each_entry(bareudp, &bn->bareudp_list, next) {
 599                 if (conf->port == bareudp->port)
 600                         t = bareudp;
 601         }
 602         return t;
 603 }
 604
 605 static int bareudp_configure(struct net *net, struct net_device *dev,
 606                              struct bareudp_conf *conf)
 607 {
 608         struct bareudp_net *bn = net_generic(net, bareudp_net_id);
 609         struct bareudp_dev *t, *bareudp = netdev_priv(dev);
 610         int err;
 611
 612         bareudp->net = net;
 613         bareudp->dev = dev;
 614         t = bareudp_find_dev(bn, conf);
 615         if (t)
 616                 return -EBUSY;
 617
 618         if (conf->multi_proto_mode &&
 619             (conf->ethertype != htons(ETH_P_MPLS_UC) &&
 620              conf->ethertype != htons(ETH_P_IP)))
 621                 return -EINVAL;
 622
 623         bareudp->port = conf->port;
 624         bareudp->ethertype = conf->ethertype;
 625         bareudp->sport_min = conf->sport_min;
 626         bareudp->multi_proto_mode = conf->multi_proto_mode;
 627
 628         err = register_netdevice(dev);
 629         if (err)
 630                 return err;
 631
 632         list_add(&bareudp->next, &bn->bareudp_list);
 633         return 0;
 634 }
 635
 636 static int bareudp_link_config(struct net_device *dev,
 637                                struct nlattr *tb[])
 638 {
 639         int err;
 640
 641         if (tb[IFLA_MTU]) {
 642                 err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
 643                 if (err)
 644                         return err;
 645         }
 646         return 0;
 647 }
 648
 649 static void bareudp_dellink(struct net_device *dev, struct list_head *head)
 650 {
 651         struct bareudp_dev *bareudp = netdev_priv(dev);
 652
 653         list_del(&bareudp->next);
 654         unregister_netdevice_queue(dev, head);
 655 }
 656
 657 static int bareudp_newlink(struct net *net, struct net_device *dev,
 658                            struct nlattr *tb[], struct nlattr *data[],
 659                            struct netlink_ext_ack *extack)
 660 {
 661         struct bareudp_conf conf;
 662         LIST_HEAD(list_kill);
 663         int err;
 664
 665         err = bareudp2info(data, &conf, extack);
 666         if (err)
 667                 return err;
 668
 669         err = bareudp_configure(net, dev, &conf);
 670         if (err)
 671                 return err;
 672
 673         err = bareudp_link_config(dev, tb);
 674         if (err)
 675                 goto err_unconfig;
 676
 677         return 0;
 678
 679 err_unconfig:
 680         bareudp_dellink(dev, &list_kill);
 681         unregister_netdevice_many(&list_kill);
 682         return err;
 683 }
 684
 685 static size_t bareudp_get_size(const struct net_device *dev)
 686 {
 687         return  nla_total_size(sizeof(__be16)) +  /* IFLA_BAREUDP_PORT */
 688                 nla_total_size(sizeof(__be16)) +  /* IFLA_BAREUDP_ETHERTYPE */
 689                 nla_total_size(sizeof(__u16))  +  /* IFLA_BAREUDP_SRCPORT_MIN */
 690                 nla_total_size(0)              +  /* IFLA_BAREUDP_MULTIPROTO_MODE */
 691                 0;
 692 }
 693
 694 static int bareudp_fill_info(struct sk_buff *skb, const struct net_device *dev)
 695 {
 696         struct bareudp_dev *bareudp = netdev_priv(dev);
 697
 698         if (nla_put_be16(skb, IFLA_BAREUDP_PORT, bareudp->port))
 699                 goto nla_put_failure;
 700         if (nla_put_be16(skb, IFLA_BAREUDP_ETHERTYPE, bareudp->ethertype))
 701                 goto nla_put_failure;
 702         if (nla_put_u16(skb, IFLA_BAREUDP_SRCPORT_MIN, bareudp->sport_min))
 703                 goto nla_put_failure;
 704         if (bareudp->multi_proto_mode &&
 705             nla_put_flag(skb, IFLA_BAREUDP_MULTIPROTO_MODE))
 706                 goto nla_put_failure;
 707
 708         return 0;
 709
 710 nla_put_failure:
 711         return -EMSGSIZE;
 712 }
 713
 714 static struct rtnl_link_ops bareudp_link_ops __read_mostly = {
 715         .kind           = "bareudp",
 716         .maxtype        = IFLA_BAREUDP_MAX,
 717         .policy         = bareudp_policy,
 718         .priv_size      = sizeof(struct bareudp_dev),
 719         .setup          = bareudp_setup,
 720         .validate       = bareudp_validate,
 721         .newlink        = bareudp_newlink,
 722         .dellink        = bareudp_dellink,
 723         .get_size       = bareudp_get_size,
 724         .fill_info      = bareudp_fill_info,
 725 };
 726
 727 struct net_device *bareudp_dev_create(struct net *net, const char *name,
 728                                       u8 name_assign_type,
 729                                       struct bareudp_conf *conf)
 730 {
 731         struct nlattr *tb[IFLA_MAX + 1];
 732         struct net_device *dev;
 733         LIST_HEAD(list_kill);
 734         int err;
 735
 736         memset(tb, 0, sizeof(tb));
 737         dev = rtnl_create_link(net, name, name_assign_type,
 738                                &bareudp_link_ops, tb, NULL);
 739         if (IS_ERR(dev))
 740                 return dev;
 741
 742         err = bareudp_configure(net, dev, conf);
 743         if (err) {
 744                 free_netdev(dev);
 745                 return ERR_PTR(err);
 746         }
 747         err = dev_set_mtu(dev, IP_MAX_MTU - BAREUDP_BASE_HLEN);
 748         if (err)
 749                 goto err;
 750
 751         err = rtnl_configure_link(dev, NULL);
 752         if (err < 0)
 753                 goto err;
 754
 755         return dev;
 756 err:
 757         bareudp_dellink(dev, &list_kill);
 758         unregister_netdevice_many(&list_kill);
 759         return ERR_PTR(err);
 760 }
 761 EXPORT_SYMBOL_GPL(bareudp_dev_create);
 762
 763 static __net_init int bareudp_init_net(struct net *net)
 764 {
 765         struct bareudp_net *bn = net_generic(net, bareudp_net_id);
 766
 767         INIT_LIST_HEAD(&bn->bareudp_list);
 768         return 0;
 769 }
 770
 771 static void bareudp_destroy_tunnels(struct net *net, struct list_head *head)
 772 {
 773         struct bareudp_net *bn = net_generic(net, bareudp_net_id);
 774         struct bareudp_dev *bareudp, *next;
 775
 776         list_for_each_entry_safe(bareudp, next, &bn->bareudp_list, next)
 777                 unregister_netdevice_queue(bareudp->dev, head);
 778 }
 779
 780 static void __net_exit bareudp_exit_batch_net(struct list_head *net_list)
 781 {
 782         struct net *net;
 783         LIST_HEAD(list);
 784
 785         rtnl_lock();
 786         list_for_each_entry(net, net_list, exit_list)
 787                 bareudp_destroy_tunnels(net, &list);
 788
 789         /* unregister the devices gathered above */
 790         unregister_netdevice_many(&list);
 791         rtnl_unlock();
 792 }
 793
 794 static struct pernet_operations bareudp_net_ops = {
 795         .init = bareudp_init_net,
 796         .exit_batch = bareudp_exit_batch_net,
 797         .id   = &bareudp_net_id,
 798         .size = sizeof(struct bareudp_net),
 799 };
 800
 801 static int __init bareudp_init_module(void)
 802 {
 803         int rc;
 804
 805         rc = register_pernet_subsys(&bareudp_net_ops);
 806         if (rc)
 807                 goto out1;
 808
 809         rc = rtnl_link_register(&bareudp_link_ops);
 810         if (rc)
 811                 goto out2;
 812
 813         return 0;
 814 out2:
 815         unregister_pernet_subsys(&bareudp_net_ops);
 816 out1:
 817         return rc;
 818 }
 819 late_initcall(bareudp_init_module);
 820
 821 static void __exit bareudp_cleanup_module(void)
 822 {
 823         rtnl_link_unregister(&bareudp_link_ops);
 824         unregister_pernet_subsys(&bareudp_net_ops);
 825 }
 826 module_exit(bareudp_cleanup_module);
 827
 828 MODULE_ALIAS_RTNL_LINK("bareudp");
 829 MODULE_LICENSE("GPL");
 830 MODULE_AUTHOR("Martin Varghese <martin.varghese@nokia.com>");
 831 MODULE_DESCRIPTION("Interface driver for UDP encapsulated traffic");