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         skb_reset_mac_header(skb);
 137
 138         if (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET)
 139                 err = IP_ECN_decapsulate(oiph, skb);
 140         else
 141                 err = IP6_ECN_decapsulate(oiph, skb);
 142
 143         if (unlikely(err)) {
 144                 if (log_ecn_error) {
 145                         if  (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET)
 146                                 net_info_ratelimited("non-ECT from %pI4 "
 147                                                      "with TOS=%#x\n",
 148                                                      &((struct iphdr *)oiph)->saddr,
 149                                                      ((struct iphdr *)oiph)->tos);
 150                         else
 151                                 net_info_ratelimited("non-ECT from %pI6\n",
 152                                                      &((struct ipv6hdr *)oiph)->saddr);
 153                 }
 154                 if (err > 1) {
 155                         ++bareudp->dev->stats.rx_frame_errors;
 156                         ++bareudp->dev->stats.rx_errors;
 157                         goto drop;
 158                 }
 159         }
 160
 161         len = skb->len;
 162         err = gro_cells_receive(&bareudp->gro_cells, skb);
 163         if (likely(err == NET_RX_SUCCESS))
 164                 dev_sw_netstats_rx_add(bareudp->dev, len);
 165
 166         return 0;
 167 drop:
 168         /* Consume bad packet */
 169         kfree_skb(skb);
 170
 171         return 0;
 172 }
 173
 174 static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
 175 {
 176         return 0;
 177 }
 178
 179 static int bareudp_init(struct net_device *dev)
 180 {
 181         struct bareudp_dev *bareudp = netdev_priv(dev);
 182         int err;
 183
 184         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 185         if (!dev->tstats)
 186                 return -ENOMEM;
 187
 188         err = gro_cells_init(&bareudp->gro_cells, dev);
 189         if (err) {
 190                 free_percpu(dev->tstats);
 191                 return err;
 192         }
 193         return 0;
 194 }
 195
 196 static void bareudp_uninit(struct net_device *dev)
 197 {
 198         struct bareudp_dev *bareudp = netdev_priv(dev);
 199
 200         gro_cells_destroy(&bareudp->gro_cells);
 201         free_percpu(dev->tstats);
 202 }
 203
 204 static struct socket *bareudp_create_sock(struct net *net, __be16 port)
 205 {
 206         struct udp_port_cfg udp_conf;
 207         struct socket *sock;
 208         int err;
 209
 210         memset(&udp_conf, 0, sizeof(udp_conf));
 211 #if IS_ENABLED(CONFIG_IPV6)
 212         udp_conf.family = AF_INET6;
 213 #else
 214         udp_conf.family = AF_INET;
 215 #endif
 216         udp_conf.local_udp_port = port;
 217         /* Open UDP socket */
 218         err = udp_sock_create(net, &udp_conf, &sock);
 219         if (err < 0)
 220                 return ERR_PTR(err);
 221
 222         udp_allow_gso(sock->sk);
 223         return sock;
 224 }
 225
 226 /* Create new listen socket if needed */
 227 static int bareudp_socket_create(struct bareudp_dev *bareudp, __be16 port)
 228 {
 229         struct udp_tunnel_sock_cfg tunnel_cfg;
 230         struct socket *sock;
 231
 232         sock = bareudp_create_sock(bareudp->net, port);
 233         if (IS_ERR(sock))
 234                 return PTR_ERR(sock);
 235
 236         /* Mark socket as an encapsulation socket */
 237         memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
 238         tunnel_cfg.sk_user_data = bareudp;
 239         tunnel_cfg.encap_type = 1;
 240         tunnel_cfg.encap_rcv = bareudp_udp_encap_recv;
 241         tunnel_cfg.encap_err_lookup = bareudp_err_lookup;
 242         tunnel_cfg.encap_destroy = NULL;
 243         setup_udp_tunnel_sock(bareudp->net, sock, &tunnel_cfg);
 244
 245         rcu_assign_pointer(bareudp->sock, sock);
 246         return 0;
 247 }
 248
 249 static int bareudp_open(struct net_device *dev)
 250 {
 251         struct bareudp_dev *bareudp = netdev_priv(dev);
 252         int ret = 0;
 253
 254         ret =  bareudp_socket_create(bareudp, bareudp->port);
 255         return ret;
 256 }
 257
 258 static void bareudp_sock_release(struct bareudp_dev *bareudp)
 259 {
 260         struct socket *sock;
 261
 262         sock = bareudp->sock;
 263         rcu_assign_pointer(bareudp->sock, NULL);
 264         synchronize_net();
 265         udp_tunnel_sock_release(sock);
 266 }
 267
 268 static int bareudp_stop(struct net_device *dev)
 269 {
 270         struct bareudp_dev *bareudp = netdev_priv(dev);
 271
 272         bareudp_sock_release(bareudp);
 273         return 0;
 274 }
 275
 276 static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 277                             struct bareudp_dev *bareudp,
 278                             const struct ip_tunnel_info *info)
 279 {
 280         bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
 281         bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
 282         struct socket *sock = rcu_dereference(bareudp->sock);
 283         bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
 284         const struct ip_tunnel_key *key = &info->key;
 285         struct rtable *rt;
 286         __be16 sport, df;
 287         int min_headroom;
 288         __u8 tos, ttl;
 289         __be32 saddr;
 290         int err;
 291
 292         if (!sock)
 293                 return -ESHUTDOWN;
 294
 295         rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr, info,
 296                                     IPPROTO_UDP, use_cache);
 297
 298         if (IS_ERR(rt))
 299                 return PTR_ERR(rt);
 300
 301         skb_tunnel_check_pmtu(skb, &rt->dst,
 302                               BAREUDP_IPV4_HLEN + info->options_len, false);
 303
 304         sport = udp_flow_src_port(bareudp->net, skb,
 305                                   bareudp->sport_min, USHRT_MAX,
 306                                   true);
 307         tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
 308         ttl = key->ttl;
 309         df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
 310         skb_scrub_packet(skb, xnet);
 311
 312         err = -ENOSPC;
 313         if (!skb_pull(skb, skb_network_offset(skb)))
 314                 goto free_dst;
 315
 316         min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len +
 317                 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
 318
 319         err = skb_cow_head(skb, min_headroom);
 320         if (unlikely(err))
 321                 goto free_dst;
 322
 323         err = udp_tunnel_handle_offloads(skb, udp_sum);
 324         if (err)
 325                 goto free_dst;
 326
 327         skb_set_inner_protocol(skb, bareudp->ethertype);
 328         udp_tunnel_xmit_skb(rt, sock->sk, skb, saddr, info->key.u.ipv4.dst,
 329                             tos, ttl, df, sport, bareudp->port,
 330                             !net_eq(bareudp->net, dev_net(bareudp->dev)),
 331                             !(info->key.tun_flags & TUNNEL_CSUM));
 332         return 0;
 333
 334 free_dst:
 335         dst_release(&rt->dst);
 336         return err;
 337 }
 338
 339 static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 340                              struct bareudp_dev *bareudp,
 341                              const struct ip_tunnel_info *info)
 342 {
 343         bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
 344         bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
 345         struct socket *sock  = rcu_dereference(bareudp->sock);
 346         bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
 347         const struct ip_tunnel_key *key = &info->key;
 348         struct dst_entry *dst = NULL;
 349         struct in6_addr saddr, daddr;
 350         int min_headroom;
 351         __u8 prio, ttl;
 352         __be16 sport;
 353         int err;
 354
 355         if (!sock)
 356                 return -ESHUTDOWN;
 357
 358         dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock, &saddr, info,
 359                                     IPPROTO_UDP, use_cache);
 360         if (IS_ERR(dst))
 361                 return PTR_ERR(dst);
 362
 363         skb_tunnel_check_pmtu(skb, dst, BAREUDP_IPV6_HLEN + info->options_len,
 364                               false);
 365
 366         sport = udp_flow_src_port(bareudp->net, skb,
 367                                   bareudp->sport_min, USHRT_MAX,
 368                                   true);
 369         prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
 370         ttl = key->ttl;
 371
 372         skb_scrub_packet(skb, xnet);
 373
 374         err = -ENOSPC;
 375         if (!skb_pull(skb, skb_network_offset(skb)))
 376                 goto free_dst;
 377
 378         min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len +
 379                 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct ipv6hdr);
 380
 381         err = skb_cow_head(skb, min_headroom);
 382         if (unlikely(err))
 383                 goto free_dst;
 384
 385         err = udp_tunnel_handle_offloads(skb, udp_sum);
 386         if (err)
 387                 goto free_dst;
 388
 389         daddr = info->key.u.ipv6.dst;
 390         udp_tunnel6_xmit_skb(dst, sock->sk, skb, dev,
 391                              &saddr, &daddr, prio, ttl,
 392                              info->key.label, sport, bareudp->port,
 393                              !(info->key.tun_flags & TUNNEL_CSUM));
 394         return 0;
 395
 396 free_dst:
 397         dst_release(dst);
 398         return err;
 399 }
 400
 401 static bool bareudp_proto_valid(struct bareudp_dev *bareudp, __be16 proto)
 402 {
 403         if (bareudp->ethertype == proto)
 404                 return true;
 405
 406         if (!bareudp->multi_proto_mode)
 407                 return false;
 408
 409         if (bareudp->ethertype == htons(ETH_P_MPLS_UC) &&
 410             proto == htons(ETH_P_MPLS_MC))
 411                 return true;
 412
 413         if (bareudp->ethertype == htons(ETH_P_IP) &&
 414             proto == htons(ETH_P_IPV6))
 415                 return true;
 416
 417         return false;
 418 }
 419
 420 static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
 421 {
 422         struct bareudp_dev *bareudp = netdev_priv(dev);
 423         struct ip_tunnel_info *info = NULL;
 424         int err;
 425
 426         if (!bareudp_proto_valid(bareudp, skb->protocol)) {
 427                 err = -EINVAL;
 428                 goto tx_error;
 429         }
 430
 431         info = skb_tunnel_info(skb);
 432         if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
 433                 err = -EINVAL;
 434                 goto tx_error;
 435         }
 436
 437         rcu_read_lock();
 438         if (IS_ENABLED(CONFIG_IPV6) && info->mode & IP_TUNNEL_INFO_IPV6)
 439                 err = bareudp6_xmit_skb(skb, dev, bareudp, info);
 440         else
 441                 err = bareudp_xmit_skb(skb, dev, bareudp, info);
 442
 443         rcu_read_unlock();
 444
 445         if (likely(!err))
 446                 return NETDEV_TX_OK;
 447 tx_error:
 448         dev_kfree_skb(skb);
 449
 450         if (err == -ELOOP)
 451                 dev->stats.collisions++;
 452         else if (err == -ENETUNREACH)
 453                 dev->stats.tx_carrier_errors++;
 454
 455         dev->stats.tx_errors++;
 456         return NETDEV_TX_OK;
 457 }
 458
 459 static int bareudp_fill_metadata_dst(struct net_device *dev,
 460                                      struct sk_buff *skb)
 461 {
 462         struct ip_tunnel_info *info = skb_tunnel_info(skb);
 463         struct bareudp_dev *bareudp = netdev_priv(dev);
 464         bool use_cache;
 465
 466         use_cache = ip_tunnel_dst_cache_usable(skb, info);
 467
 468         if (!IS_ENABLED(CONFIG_IPV6) || ip_tunnel_info_af(info) == AF_INET) {
 469                 struct rtable *rt;
 470                 __be32 saddr;
 471
 472                 rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr,
 473                                             info, IPPROTO_UDP, use_cache);
 474                 if (IS_ERR(rt))
 475                         return PTR_ERR(rt);
 476
 477                 ip_rt_put(rt);
 478                 info->key.u.ipv4.src = saddr;
 479         } else if (ip_tunnel_info_af(info) == AF_INET6) {
 480                 struct dst_entry *dst;
 481                 struct in6_addr saddr;
 482                 struct socket *sock = rcu_dereference(bareudp->sock);
 483
 484                 dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock,
 485                                             &saddr, info, IPPROTO_UDP,
 486                                             use_cache);
 487                 if (IS_ERR(dst))
 488                         return PTR_ERR(dst);
 489
 490                 dst_release(dst);
 491                 info->key.u.ipv6.src = saddr;
 492         } else {
 493                 return -EINVAL;
 494         }
 495
 496         info->key.tp_src = udp_flow_src_port(bareudp->net, skb,
 497                                              bareudp->sport_min,
 498                         USHRT_MAX, true);
 499         info->key.tp_dst = bareudp->port;
 500         return 0;
 501 }
 502
 503 static const struct net_device_ops bareudp_netdev_ops = {
 504         .ndo_init               = bareudp_init,
 505         .ndo_uninit             = bareudp_uninit,
 506         .ndo_open               = bareudp_open,
 507         .ndo_stop               = bareudp_stop,
 508         .ndo_start_xmit         = bareudp_xmit,
 509         .ndo_get_stats64        = dev_get_tstats64,
 510         .ndo_fill_metadata_dst  = bareudp_fill_metadata_dst,
 511 };
 512
 513 static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
 514         [IFLA_BAREUDP_PORT]                = { .type = NLA_U16 },
 515         [IFLA_BAREUDP_ETHERTYPE]           = { .type = NLA_U16 },
 516         [IFLA_BAREUDP_SRCPORT_MIN]         = { .type = NLA_U16 },
 517         [IFLA_BAREUDP_MULTIPROTO_MODE]     = { .type = NLA_FLAG },
 518 };
 519
 520 /* Info for udev, that this is a virtual tunnel endpoint */
 521 static const struct device_type bareudp_type = {
 522         .name = "bareudp",
 523 };
 524
 525 /* Initialize the device structure. */
 526 static void bareudp_setup(struct net_device *dev)
 527 {
 528         dev->netdev_ops = &bareudp_netdev_ops;
 529         dev->needs_free_netdev = true;
 530         SET_NETDEV_DEVTYPE(dev, &bareudp_type);
 531         dev->features    |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
 532         dev->features    |= NETIF_F_RXCSUM;
 533         dev->features    |= NETIF_F_LLTX;
 534         dev->features    |= NETIF_F_GSO_SOFTWARE;
 535         dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
 536         dev->hw_features |= NETIF_F_RXCSUM;
 537         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
 538         dev->hard_header_len = 0;
 539         dev->addr_len = 0;
 540         dev->mtu = ETH_DATA_LEN;
 541         dev->min_mtu = IPV4_MIN_MTU;
 542         dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
 543         dev->type = ARPHRD_NONE;
 544         netif_keep_dst(dev);
 545         dev->priv_flags |= IFF_NO_QUEUE;
 546         dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 547 }
 548
 549 static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
 550                             struct netlink_ext_ack *extack)
 551 {
 552         if (!data) {
 553                 NL_SET_ERR_MSG(extack,
 554                                "Not enough attributes provided to perform the operation");
 555                 return -EINVAL;
 556         }
 557         return 0;
 558 }
 559
 560 static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf,
 561                         struct netlink_ext_ack *extack)
 562 {
 563         memset(conf, 0, sizeof(*conf));
 564
 565         if (!data[IFLA_BAREUDP_PORT]) {
 566                 NL_SET_ERR_MSG(extack, "port not specified");
 567                 return -EINVAL;
 568         }
 569         if (!data[IFLA_BAREUDP_ETHERTYPE]) {
 570                 NL_SET_ERR_MSG(extack, "ethertype not specified");
 571                 return -EINVAL;
 572         }
 573
 574         if (data[IFLA_BAREUDP_PORT])
 575                 conf->port =  nla_get_u16(data[IFLA_BAREUDP_PORT]);
 576
 577         if (data[IFLA_BAREUDP_ETHERTYPE])
 578                 conf->ethertype =  nla_get_u16(data[IFLA_BAREUDP_ETHERTYPE]);
 579
 580         if (data[IFLA_BAREUDP_SRCPORT_MIN])
 581                 conf->sport_min =  nla_get_u16(data[IFLA_BAREUDP_SRCPORT_MIN]);
 582
 583         if (data[IFLA_BAREUDP_MULTIPROTO_MODE])
 584                 conf->multi_proto_mode = true;
 585
 586         return 0;
 587 }
 588
 589 static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
 590                                             const struct bareudp_conf *conf)
 591 {
 592         struct bareudp_dev *bareudp, *t = NULL;
 593
 594         list_for_each_entry(bareudp, &bn->bareudp_list, next) {
 595                 if (conf->port == bareudp->port)
 596                         t = bareudp;
 597         }
 598         return t;
 599 }
 600
 601 static int bareudp_configure(struct net *net, struct net_device *dev,
 602                              struct bareudp_conf *conf)
 603 {
 604         struct bareudp_net *bn = net_generic(net, bareudp_net_id);
 605         struct bareudp_dev *t, *bareudp = netdev_priv(dev);
 606         int err;
 607
 608         bareudp->net = net;
 609         bareudp->dev = dev;
 610         t = bareudp_find_dev(bn, conf);
 611         if (t)
 612                 return -EBUSY;
 613
 614         if (conf->multi_proto_mode &&
 615             (conf->ethertype != htons(ETH_P_MPLS_UC) &&
 616              conf->ethertype != htons(ETH_P_IP)))
 617                 return -EINVAL;
 618
 619         bareudp->port = conf->port;
 620         bareudp->ethertype = conf->ethertype;
 621         bareudp->sport_min = conf->sport_min;
 622         bareudp->multi_proto_mode = conf->multi_proto_mode;
 623
 624         err = register_netdevice(dev);
 625         if (err)
 626                 return err;
 627
 628         list_add(&bareudp->next, &bn->bareudp_list);
 629         return 0;
 630 }
 631
 632 static int bareudp_link_config(struct net_device *dev,
 633                                struct nlattr *tb[])
 634 {
 635         int err;
 636
 637         if (tb[IFLA_MTU]) {
 638                 err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
 639                 if (err)
 640                         return err;
 641         }
 642         return 0;
 643 }
 644
 645 static void bareudp_dellink(struct net_device *dev, struct list_head *head)
 646 {
 647         struct bareudp_dev *bareudp = netdev_priv(dev);
 648
 649         list_del(&bareudp->next);
 650         unregister_netdevice_queue(dev, head);
 651 }
 652
 653 static int bareudp_newlink(struct net *net, struct net_device *dev,
 654                            struct nlattr *tb[], struct nlattr *data[],
 655                            struct netlink_ext_ack *extack)
 656 {
 657         struct bareudp_conf conf;
 658         int err;
 659
 660         err = bareudp2info(data, &conf, extack);
 661         if (err)
 662                 return err;
 663
 664         err = bareudp_configure(net, dev, &conf);
 665         if (err)
 666                 return err;
 667
 668         err = bareudp_link_config(dev, tb);
 669         if (err)
 670                 goto err_unconfig;
 671
 672         return 0;
 673
 674 err_unconfig:
 675         bareudp_dellink(dev, NULL);
 676         return err;
 677 }
 678
 679 static size_t bareudp_get_size(const struct net_device *dev)
 680 {
 681         return  nla_total_size(sizeof(__be16)) +  /* IFLA_BAREUDP_PORT */
 682                 nla_total_size(sizeof(__be16)) +  /* IFLA_BAREUDP_ETHERTYPE */
 683                 nla_total_size(sizeof(__u16))  +  /* IFLA_BAREUDP_SRCPORT_MIN */
 684                 nla_total_size(0)              +  /* IFLA_BAREUDP_MULTIPROTO_MODE */
 685                 0;
 686 }
 687
 688 static int bareudp_fill_info(struct sk_buff *skb, const struct net_device *dev)
 689 {
 690         struct bareudp_dev *bareudp = netdev_priv(dev);
 691
 692         if (nla_put_be16(skb, IFLA_BAREUDP_PORT, bareudp->port))
 693                 goto nla_put_failure;
 694         if (nla_put_be16(skb, IFLA_BAREUDP_ETHERTYPE, bareudp->ethertype))
 695                 goto nla_put_failure;
 696         if (nla_put_u16(skb, IFLA_BAREUDP_SRCPORT_MIN, bareudp->sport_min))
 697                 goto nla_put_failure;
 698         if (bareudp->multi_proto_mode &&
 699             nla_put_flag(skb, IFLA_BAREUDP_MULTIPROTO_MODE))
 700                 goto nla_put_failure;
 701
 702         return 0;
 703
 704 nla_put_failure:
 705         return -EMSGSIZE;
 706 }
 707
 708 static struct rtnl_link_ops bareudp_link_ops __read_mostly = {
 709         .kind           = "bareudp",
 710         .maxtype        = IFLA_BAREUDP_MAX,
 711         .policy         = bareudp_policy,
 712         .priv_size      = sizeof(struct bareudp_dev),
 713         .setup          = bareudp_setup,
 714         .validate       = bareudp_validate,
 715         .newlink        = bareudp_newlink,
 716         .dellink        = bareudp_dellink,
 717         .get_size       = bareudp_get_size,
 718         .fill_info      = bareudp_fill_info,
 719 };
 720
 721 struct net_device *bareudp_dev_create(struct net *net, const char *name,
 722                                       u8 name_assign_type,
 723                                       struct bareudp_conf *conf)
 724 {
 725         struct nlattr *tb[IFLA_MAX + 1];
 726         struct net_device *dev;
 727         int err;
 728
 729         memset(tb, 0, sizeof(tb));
 730         dev = rtnl_create_link(net, name, name_assign_type,
 731                                &bareudp_link_ops, tb, NULL);
 732         if (IS_ERR(dev))
 733                 return dev;
 734
 735         err = bareudp_configure(net, dev, conf);
 736         if (err) {
 737                 free_netdev(dev);
 738                 return ERR_PTR(err);
 739         }
 740         err = dev_set_mtu(dev, IP_MAX_MTU - BAREUDP_BASE_HLEN);
 741         if (err)
 742                 goto err;
 743
 744         err = rtnl_configure_link(dev, NULL);
 745         if (err < 0)
 746                 goto err;
 747
 748         return dev;
 749 err:
 750         bareudp_dellink(dev, NULL);
 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");