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         skb_reset_mac_header(skb);
 143
 144         if (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET)
 145                 err = IP_ECN_decapsulate(oiph, skb);
 146         else
 147                 err = IP6_ECN_decapsulate(oiph, skb);
 148
 149         if (unlikely(err)) {
 150                 if (log_ecn_error) {
 151                         if  (!IS_ENABLED(CONFIG_IPV6) || family == AF_INET)
 152                                 net_info_ratelimited("non-ECT from %pI4 "
 153                                                      "with TOS=%#x\n",
 154                                                      &((struct iphdr *)oiph)->saddr,
 155                                                      ((struct iphdr *)oiph)->tos);
 156                         else
 157                                 net_info_ratelimited("non-ECT from %pI6\n",
 158                                                      &((struct ipv6hdr *)oiph)->saddr);
 159                 }
 160                 if (err > 1) {
 161                         ++bareudp->dev->stats.rx_frame_errors;
 162                         ++bareudp->dev->stats.rx_errors;
 163                         goto drop;
 164                 }
 165         }
 166
 167         len = skb->len;
 168         err = gro_cells_receive(&bareudp->gro_cells, skb);
 169         if (likely(err == NET_RX_SUCCESS))
 170                 dev_sw_netstats_rx_add(bareudp->dev, len);
 171
 172         return 0;
 173 drop:
 174         /* Consume bad packet */
 175         kfree_skb(skb);
 176
 177         return 0;
 178 }
 179
 180 static int bareudp_err_lookup(struct sock *sk, struct sk_buff *skb)
 181 {
 182         return 0;
 183 }
 184
 185 static int bareudp_init(struct net_device *dev)
 186 {
 187         struct bareudp_dev *bareudp = netdev_priv(dev);
 188         int err;
 189
 190         dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
 191         if (!dev->tstats)
 192                 return -ENOMEM;
 193
 194         err = gro_cells_init(&bareudp->gro_cells, dev);
 195         if (err) {
 196                 free_percpu(dev->tstats);
 197                 return err;
 198         }
 199         return 0;
 200 }
 201
 202 static void bareudp_uninit(struct net_device *dev)
 203 {
 204         struct bareudp_dev *bareudp = netdev_priv(dev);
 205
 206         gro_cells_destroy(&bareudp->gro_cells);
 207         free_percpu(dev->tstats);
 208 }
 209
 210 static struct socket *bareudp_create_sock(struct net *net, __be16 port)
 211 {
 212         struct udp_port_cfg udp_conf;
 213         struct socket *sock;
 214         int err;
 215
 216         memset(&udp_conf, 0, sizeof(udp_conf));
 217 #if IS_ENABLED(CONFIG_IPV6)
 218         udp_conf.family = AF_INET6;
 219 #else
 220         udp_conf.family = AF_INET;
 221 #endif
 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         udp_allow_gso(sock->sk);
 229         return sock;
 230 }
 231
 232 /* Create new listen socket if needed */
 233 static int bareudp_socket_create(struct bareudp_dev *bareudp, __be16 port)
 234 {
 235         struct udp_tunnel_sock_cfg tunnel_cfg;
 236         struct socket *sock;
 237
 238         sock = bareudp_create_sock(bareudp->net, port);
 239         if (IS_ERR(sock))
 240                 return PTR_ERR(sock);
 241
 242         /* Mark socket as an encapsulation socket */
 243         memset(&tunnel_cfg, 0, sizeof(tunnel_cfg));
 244         tunnel_cfg.sk_user_data = bareudp;
 245         tunnel_cfg.encap_type = 1;
 246         tunnel_cfg.encap_rcv = bareudp_udp_encap_recv;
 247         tunnel_cfg.encap_err_lookup = bareudp_err_lookup;
 248         tunnel_cfg.encap_destroy = NULL;
 249         setup_udp_tunnel_sock(bareudp->net, sock, &tunnel_cfg);
 250
 251         rcu_assign_pointer(bareudp->sock, sock);
 252         return 0;
 253 }
 254
 255 static int bareudp_open(struct net_device *dev)
 256 {
 257         struct bareudp_dev *bareudp = netdev_priv(dev);
 258         int ret = 0;
 259
 260         ret =  bareudp_socket_create(bareudp, bareudp->port);
 261         return ret;
 262 }
 263
 264 static void bareudp_sock_release(struct bareudp_dev *bareudp)
 265 {
 266         struct socket *sock;
 267
 268         sock = bareudp->sock;
 269         rcu_assign_pointer(bareudp->sock, NULL);
 270         synchronize_net();
 271         udp_tunnel_sock_release(sock);
 272 }
 273
 274 static int bareudp_stop(struct net_device *dev)
 275 {
 276         struct bareudp_dev *bareudp = netdev_priv(dev);
 277
 278         bareudp_sock_release(bareudp);
 279         return 0;
 280 }
 281
 282 static int bareudp_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 283                             struct bareudp_dev *bareudp,
 284                             const struct ip_tunnel_info *info)
 285 {
 286         bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
 287         bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
 288         struct socket *sock = rcu_dereference(bareudp->sock);
 289         bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
 290         const struct ip_tunnel_key *key = &info->key;
 291         struct rtable *rt;
 292         __be16 sport, df;
 293         int min_headroom;
 294         __u8 tos, ttl;
 295         __be32 saddr;
 296         int err;
 297
 298         if (!sock)
 299                 return -ESHUTDOWN;
 300
 301         rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr, info,
 302                                     IPPROTO_UDP, use_cache);
 303
 304         if (IS_ERR(rt))
 305                 return PTR_ERR(rt);
 306
 307         skb_tunnel_check_pmtu(skb, &rt->dst,
 308                               BAREUDP_IPV4_HLEN + info->options_len, false);
 309
 310         sport = udp_flow_src_port(bareudp->net, skb,
 311                                   bareudp->sport_min, USHRT_MAX,
 312                                   true);
 313         tos = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
 314         ttl = key->ttl;
 315         df = key->tun_flags & TUNNEL_DONT_FRAGMENT ? htons(IP_DF) : 0;
 316         skb_scrub_packet(skb, xnet);
 317
 318         err = -ENOSPC;
 319         if (!skb_pull(skb, skb_network_offset(skb)))
 320                 goto free_dst;
 321
 322         min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len +
 323                 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct iphdr);
 324
 325         err = skb_cow_head(skb, min_headroom);
 326         if (unlikely(err))
 327                 goto free_dst;
 328
 329         err = udp_tunnel_handle_offloads(skb, udp_sum);
 330         if (err)
 331                 goto free_dst;
 332
 333         skb_set_inner_protocol(skb, bareudp->ethertype);
 334         udp_tunnel_xmit_skb(rt, sock->sk, skb, saddr, info->key.u.ipv4.dst,
 335                             tos, ttl, df, sport, bareudp->port,
 336                             !net_eq(bareudp->net, dev_net(bareudp->dev)),
 337                             !(info->key.tun_flags & TUNNEL_CSUM));
 338         return 0;
 339
 340 free_dst:
 341         dst_release(&rt->dst);
 342         return err;
 343 }
 344
 345 static int bareudp6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
 346                              struct bareudp_dev *bareudp,
 347                              const struct ip_tunnel_info *info)
 348 {
 349         bool xnet = !net_eq(bareudp->net, dev_net(bareudp->dev));
 350         bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
 351         struct socket *sock  = rcu_dereference(bareudp->sock);
 352         bool udp_sum = !!(info->key.tun_flags & TUNNEL_CSUM);
 353         const struct ip_tunnel_key *key = &info->key;
 354         struct dst_entry *dst = NULL;
 355         struct in6_addr saddr, daddr;
 356         int min_headroom;
 357         __u8 prio, ttl;
 358         __be16 sport;
 359         int err;
 360
 361         if (!sock)
 362                 return -ESHUTDOWN;
 363
 364         dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock, &saddr, info,
 365                                     IPPROTO_UDP, use_cache);
 366         if (IS_ERR(dst))
 367                 return PTR_ERR(dst);
 368
 369         skb_tunnel_check_pmtu(skb, dst, BAREUDP_IPV6_HLEN + info->options_len,
 370                               false);
 371
 372         sport = udp_flow_src_port(bareudp->net, skb,
 373                                   bareudp->sport_min, USHRT_MAX,
 374                                   true);
 375         prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
 376         ttl = key->ttl;
 377
 378         skb_scrub_packet(skb, xnet);
 379
 380         err = -ENOSPC;
 381         if (!skb_pull(skb, skb_network_offset(skb)))
 382                 goto free_dst;
 383
 384         min_headroom = LL_RESERVED_SPACE(dst->dev) + dst->header_len +
 385                 BAREUDP_BASE_HLEN + info->options_len + sizeof(struct ipv6hdr);
 386
 387         err = skb_cow_head(skb, min_headroom);
 388         if (unlikely(err))
 389                 goto free_dst;
 390
 391         err = udp_tunnel_handle_offloads(skb, udp_sum);
 392         if (err)
 393                 goto free_dst;
 394
 395         daddr = info->key.u.ipv6.dst;
 396         udp_tunnel6_xmit_skb(dst, sock->sk, skb, dev,
 397                              &saddr, &daddr, prio, ttl,
 398                              info->key.label, sport, bareudp->port,
 399                              !(info->key.tun_flags & TUNNEL_CSUM));
 400         return 0;
 401
 402 free_dst:
 403         dst_release(dst);
 404         return err;
 405 }
 406
 407 static bool bareudp_proto_valid(struct bareudp_dev *bareudp, __be16 proto)
 408 {
 409         if (bareudp->ethertype == proto)
 410                 return true;
 411
 412         if (!bareudp->multi_proto_mode)
 413                 return false;
 414
 415         if (bareudp->ethertype == htons(ETH_P_MPLS_UC) &&
 416             proto == htons(ETH_P_MPLS_MC))
 417                 return true;
 418
 419         if (bareudp->ethertype == htons(ETH_P_IP) &&
 420             proto == htons(ETH_P_IPV6))
 421                 return true;
 422
 423         return false;
 424 }
 425
 426 static netdev_tx_t bareudp_xmit(struct sk_buff *skb, struct net_device *dev)
 427 {
 428         struct bareudp_dev *bareudp = netdev_priv(dev);
 429         struct ip_tunnel_info *info = NULL;
 430         int err;
 431
 432         if (!bareudp_proto_valid(bareudp, skb->protocol)) {
 433                 err = -EINVAL;
 434                 goto tx_error;
 435         }
 436
 437         info = skb_tunnel_info(skb);
 438         if (unlikely(!info || !(info->mode & IP_TUNNEL_INFO_TX))) {
 439                 err = -EINVAL;
 440                 goto tx_error;
 441         }
 442
 443         rcu_read_lock();
 444         if (IS_ENABLED(CONFIG_IPV6) && info->mode & IP_TUNNEL_INFO_IPV6)
 445                 err = bareudp6_xmit_skb(skb, dev, bareudp, info);
 446         else
 447                 err = bareudp_xmit_skb(skb, dev, bareudp, info);
 448
 449         rcu_read_unlock();
 450
 451         if (likely(!err))
 452                 return NETDEV_TX_OK;
 453 tx_error:
 454         dev_kfree_skb(skb);
 455
 456         if (err == -ELOOP)
 457                 dev->stats.collisions++;
 458         else if (err == -ENETUNREACH)
 459                 dev->stats.tx_carrier_errors++;
 460
 461         dev->stats.tx_errors++;
 462         return NETDEV_TX_OK;
 463 }
 464
 465 static int bareudp_fill_metadata_dst(struct net_device *dev,
 466                                      struct sk_buff *skb)
 467 {
 468         struct ip_tunnel_info *info = skb_tunnel_info(skb);
 469         struct bareudp_dev *bareudp = netdev_priv(dev);
 470         bool use_cache;
 471
 472         use_cache = ip_tunnel_dst_cache_usable(skb, info);
 473
 474         if (!IS_ENABLED(CONFIG_IPV6) || ip_tunnel_info_af(info) == AF_INET) {
 475                 struct rtable *rt;
 476                 __be32 saddr;
 477
 478                 rt = ip_route_output_tunnel(skb, dev, bareudp->net, &saddr,
 479                                             info, IPPROTO_UDP, use_cache);
 480                 if (IS_ERR(rt))
 481                         return PTR_ERR(rt);
 482
 483                 ip_rt_put(rt);
 484                 info->key.u.ipv4.src = saddr;
 485         } else if (ip_tunnel_info_af(info) == AF_INET6) {
 486                 struct dst_entry *dst;
 487                 struct in6_addr saddr;
 488                 struct socket *sock = rcu_dereference(bareudp->sock);
 489
 490                 dst = ip6_dst_lookup_tunnel(skb, dev, bareudp->net, sock,
 491                                             &saddr, info, IPPROTO_UDP,
 492                                             use_cache);
 493                 if (IS_ERR(dst))
 494                         return PTR_ERR(dst);
 495
 496                 dst_release(dst);
 497                 info->key.u.ipv6.src = saddr;
 498         } else {
 499                 return -EINVAL;
 500         }
 501
 502         info->key.tp_src = udp_flow_src_port(bareudp->net, skb,
 503                                              bareudp->sport_min,
 504                         USHRT_MAX, true);
 505         info->key.tp_dst = bareudp->port;
 506         return 0;
 507 }
 508
 509 static const struct net_device_ops bareudp_netdev_ops = {
 510         .ndo_init               = bareudp_init,
 511         .ndo_uninit             = bareudp_uninit,
 512         .ndo_open               = bareudp_open,
 513         .ndo_stop               = bareudp_stop,
 514         .ndo_start_xmit         = bareudp_xmit,
 515         .ndo_get_stats64        = dev_get_tstats64,
 516         .ndo_fill_metadata_dst  = bareudp_fill_metadata_dst,
 517 };
 518
 519 static const struct nla_policy bareudp_policy[IFLA_BAREUDP_MAX + 1] = {
 520         [IFLA_BAREUDP_PORT]                = { .type = NLA_U16 },
 521         [IFLA_BAREUDP_ETHERTYPE]           = { .type = NLA_U16 },
 522         [IFLA_BAREUDP_SRCPORT_MIN]         = { .type = NLA_U16 },
 523         [IFLA_BAREUDP_MULTIPROTO_MODE]     = { .type = NLA_FLAG },
 524 };
 525
 526 /* Info for udev, that this is a virtual tunnel endpoint */
 527 static const struct device_type bareudp_type = {
 528         .name = "bareudp",
 529 };
 530
 531 /* Initialize the device structure. */
 532 static void bareudp_setup(struct net_device *dev)
 533 {
 534         dev->netdev_ops = &bareudp_netdev_ops;
 535         dev->needs_free_netdev = true;
 536         SET_NETDEV_DEVTYPE(dev, &bareudp_type);
 537         dev->features    |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
 538         dev->features    |= NETIF_F_RXCSUM;
 539         dev->features    |= NETIF_F_LLTX;
 540         dev->features    |= NETIF_F_GSO_SOFTWARE;
 541         dev->hw_features |= NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_FRAGLIST;
 542         dev->hw_features |= NETIF_F_RXCSUM;
 543         dev->hw_features |= NETIF_F_GSO_SOFTWARE;
 544         dev->hard_header_len = 0;
 545         dev->addr_len = 0;
 546         dev->mtu = ETH_DATA_LEN;
 547         dev->min_mtu = IPV4_MIN_MTU;
 548         dev->max_mtu = IP_MAX_MTU - BAREUDP_BASE_HLEN;
 549         dev->type = ARPHRD_NONE;
 550         netif_keep_dst(dev);
 551         dev->priv_flags |= IFF_NO_QUEUE;
 552         dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
 553 }
 554
 555 static int bareudp_validate(struct nlattr *tb[], struct nlattr *data[],
 556                             struct netlink_ext_ack *extack)
 557 {
 558         if (!data) {
 559                 NL_SET_ERR_MSG(extack,
 560                                "Not enough attributes provided to perform the operation");
 561                 return -EINVAL;
 562         }
 563         return 0;
 564 }
 565
 566 static int bareudp2info(struct nlattr *data[], struct bareudp_conf *conf,
 567                         struct netlink_ext_ack *extack)
 568 {
 569         memset(conf, 0, sizeof(*conf));
 570
 571         if (!data[IFLA_BAREUDP_PORT]) {
 572                 NL_SET_ERR_MSG(extack, "port not specified");
 573                 return -EINVAL;
 574         }
 575         if (!data[IFLA_BAREUDP_ETHERTYPE]) {
 576                 NL_SET_ERR_MSG(extack, "ethertype not specified");
 577                 return -EINVAL;
 578         }
 579
 580         if (data[IFLA_BAREUDP_PORT])
 581                 conf->port =  nla_get_u16(data[IFLA_BAREUDP_PORT]);
 582
 583         if (data[IFLA_BAREUDP_ETHERTYPE])
 584                 conf->ethertype =  nla_get_u16(data[IFLA_BAREUDP_ETHERTYPE]);
 585
 586         if (data[IFLA_BAREUDP_SRCPORT_MIN])
 587                 conf->sport_min =  nla_get_u16(data[IFLA_BAREUDP_SRCPORT_MIN]);
 588
 589         if (data[IFLA_BAREUDP_MULTIPROTO_MODE])
 590                 conf->multi_proto_mode = true;
 591
 592         return 0;
 593 }
 594
 595 static struct bareudp_dev *bareudp_find_dev(struct bareudp_net *bn,
 596                                             const struct bareudp_conf *conf)
 597 {
 598         struct bareudp_dev *bareudp, *t = NULL;
 599
 600         list_for_each_entry(bareudp, &bn->bareudp_list, next) {
 601                 if (conf->port == bareudp->port)
 602                         t = bareudp;
 603         }
 604         return t;
 605 }
 606
 607 static int bareudp_configure(struct net *net, struct net_device *dev,
 608                              struct bareudp_conf *conf)
 609 {
 610         struct bareudp_net *bn = net_generic(net, bareudp_net_id);
 611         struct bareudp_dev *t, *bareudp = netdev_priv(dev);
 612         int err;
 613
 614         bareudp->net = net;
 615         bareudp->dev = dev;
 616         t = bareudp_find_dev(bn, conf);
 617         if (t)
 618                 return -EBUSY;
 619
 620         if (conf->multi_proto_mode &&
 621             (conf->ethertype != htons(ETH_P_MPLS_UC) &&
 622              conf->ethertype != htons(ETH_P_IP)))
 623                 return -EINVAL;
 624
 625         bareudp->port = conf->port;
 626         bareudp->ethertype = conf->ethertype;
 627         bareudp->sport_min = conf->sport_min;
 628         bareudp->multi_proto_mode = conf->multi_proto_mode;
 629
 630         err = register_netdevice(dev);
 631         if (err)
 632                 return err;
 633
 634         list_add(&bareudp->next, &bn->bareudp_list);
 635         return 0;
 636 }
 637
 638 static int bareudp_link_config(struct net_device *dev,
 639                                struct nlattr *tb[])
 640 {
 641         int err;
 642
 643         if (tb[IFLA_MTU]) {
 644                 err = dev_set_mtu(dev, nla_get_u32(tb[IFLA_MTU]));
 645                 if (err)
 646                         return err;
 647         }
 648         return 0;
 649 }
 650
 651 static void bareudp_dellink(struct net_device *dev, struct list_head *head)
 652 {
 653         struct bareudp_dev *bareudp = netdev_priv(dev);
 654
 655         list_del(&bareudp->next);
 656         unregister_netdevice_queue(dev, head);
 657 }
 658
 659 static int bareudp_newlink(struct net *net, struct net_device *dev,
 660                            struct nlattr *tb[], struct nlattr *data[],
 661                            struct netlink_ext_ack *extack)
 662 {
 663         struct bareudp_conf conf;
 664         int err;
 665
 666         err = bareudp2info(data, &conf, extack);
 667         if (err)
 668                 return err;
 669
 670         err = bareudp_configure(net, dev, &conf);
 671         if (err)
 672                 return err;
 673
 674         err = bareudp_link_config(dev, tb);
 675         if (err)
 676                 goto err_unconfig;
 677
 678         return 0;
 679
 680 err_unconfig:
 681         bareudp_dellink(dev, NULL);
 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         int err;
 734
 735         memset(tb, 0, sizeof(tb));
 736         dev = rtnl_create_link(net, name, name_assign_type,
 737                                &bareudp_link_ops, tb, NULL);
 738         if (IS_ERR(dev))
 739                 return dev;
 740
 741         err = bareudp_configure(net, dev, conf);
 742         if (err) {
 743                 free_netdev(dev);
 744                 return ERR_PTR(err);
 745         }
 746         err = dev_set_mtu(dev, IP_MAX_MTU - BAREUDP_BASE_HLEN);
 747         if (err)
 748                 goto err;
 749
 750         err = rtnl_configure_link(dev, NULL);
 751         if (err < 0)
 752                 goto err;
 753
 754         return dev;
 755 err:
 756         bareudp_dellink(dev, NULL);
 757         return ERR_PTR(err);
 758 }
 759 EXPORT_SYMBOL_GPL(bareudp_dev_create);
 760
 761 static __net_init int bareudp_init_net(struct net *net)
 762 {
 763         struct bareudp_net *bn = net_generic(net, bareudp_net_id);
 764
 765         INIT_LIST_HEAD(&bn->bareudp_list);
 766         return 0;
 767 }
 768
 769 static void bareudp_destroy_tunnels(struct net *net, struct list_head *head)
 770 {
 771         struct bareudp_net *bn = net_generic(net, bareudp_net_id);
 772         struct bareudp_dev *bareudp, *next;
 773
 774         list_for_each_entry_safe(bareudp, next, &bn->bareudp_list, next)
 775                 unregister_netdevice_queue(bareudp->dev, head);
 776 }
 777
 778 static void __net_exit bareudp_exit_batch_net(struct list_head *net_list)
 779 {
 780         struct net *net;
 781         LIST_HEAD(list);
 782
 783         rtnl_lock();
 784         list_for_each_entry(net, net_list, exit_list)
 785                 bareudp_destroy_tunnels(net, &list);
 786
 787         /* unregister the devices gathered above */
 788         unregister_netdevice_many(&list);
 789         rtnl_unlock();
 790 }
 791
 792 static struct pernet_operations bareudp_net_ops = {
 793         .init = bareudp_init_net,
 794         .exit_batch = bareudp_exit_batch_net,
 795         .id   = &bareudp_net_id,
 796         .size = sizeof(struct bareudp_net),
 797 };
 798
 799 static int __init bareudp_init_module(void)
 800 {
 801         int rc;
 802
 803         rc = register_pernet_subsys(&bareudp_net_ops);
 804         if (rc)
 805                 goto out1;
 806
 807         rc = rtnl_link_register(&bareudp_link_ops);
 808         if (rc)
 809                 goto out2;
 810
 811         return 0;
 812 out2:
 813         unregister_pernet_subsys(&bareudp_net_ops);
 814 out1:
 815         return rc;
 816 }
 817 late_initcall(bareudp_init_module);
 818
 819 static void __exit bareudp_cleanup_module(void)
 820 {
 821         rtnl_link_unregister(&bareudp_link_ops);
 822         unregister_pernet_subsys(&bareudp_net_ops);
 823 }
 824 module_exit(bareudp_cleanup_module);
 825
 826 MODULE_ALIAS_RTNL_LINK("bareudp");
 827 MODULE_LICENSE("GPL");
 828 MODULE_AUTHOR("Martin Varghese <martin.varghese@nokia.com>");
 829 MODULE_DESCRIPTION("Interface driver for UDP encapsulated traffic");