net/tipc/udp_media.c

   1 /* net/tipc/udp_media.c: IP bearer support for TIPC
   2  *
   3  * Copyright (c) 2015, Ericsson AB
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  * 3. Neither the names of the copyright holders nor the names of its
  15  *    contributors may be used to endorse or promote products derived from
  16  *    this software without specific prior written permission.
  17  *
  18  * Alternatively, this software may be distributed under the terms of the
  19  * GNU General Public License ("GPL") version 2 as published by the Free
  20  * Software Foundation.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  23  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  26  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  32  * POSSIBILITY OF SUCH DAMAGE.
  33  */
  34
  35 #include <linux/socket.h>
  36 #include <linux/ip.h>
  37 #include <linux/udp.h>
  38 #include <linux/inet.h>
  39 #include <linux/inetdevice.h>
  40 #include <linux/igmp.h>
  41 #include <linux/kernel.h>
  42 #include <linux/workqueue.h>
  43 #include <linux/list.h>
  44 #include <net/sock.h>
  45 #include <net/ip.h>
  46 #include <net/udp_tunnel.h>
  47 #include <net/ipv6_stubs.h>
  48 #include <linux/tipc_netlink.h>
  49 #include "core.h"
  50 #include "addr.h"
  51 #include "net.h"
  52 #include "bearer.h"
  53 #include "netlink.h"
  54 #include "msg.h"
  55
  56 /* IANA assigned UDP port */
  57 #define UDP_PORT_DEFAULT        6118
  58
  59 #define UDP_MIN_HEADROOM        48
  60
  61 /**
  62  * struct udp_media_addr - IP/UDP addressing information
  63  *
  64  * This is the bearer level originating address used in neighbor discovery
  65  * messages, and all fields should be in network byte order
  66  */
  67 struct udp_media_addr {
  68         __be16  proto;
  69         __be16  port;
  70         union {
  71                 struct in_addr ipv4;
  72                 struct in6_addr ipv6;
  73         };
  74 };
  75
  76 /* struct udp_replicast - container for UDP remote addresses */
  77 struct udp_replicast {
  78         struct udp_media_addr addr;
  79         struct rcu_head rcu;
  80         struct list_head list;
  81 };
  82
  83 /**
  84  * struct udp_bearer - ip/udp bearer data structure
  85  * @bearer:     associated generic tipc bearer
  86  * @ubsock:     bearer associated socket
  87  * @ifindex:    local address scope
  88  * @work:       used to schedule deferred work on a bearer
  89  */
  90 struct udp_bearer {
  91         struct tipc_bearer __rcu *bearer;
  92         struct socket *ubsock;
  93         u32 ifindex;
  94         struct work_struct work;
  95         struct udp_replicast rcast;
  96 };
  97
  98 static int tipc_udp_is_mcast_addr(struct udp_media_addr *addr)
  99 {
 100         if (ntohs(addr->proto) == ETH_P_IP)
 101                 return ipv4_is_multicast(addr->ipv4.s_addr);
 102 #if IS_ENABLED(CONFIG_IPV6)
 103         else
 104                 return ipv6_addr_is_multicast(&addr->ipv6);
 105 #endif
 106         return 0;
 107 }
 108
 109 /* udp_media_addr_set - convert a ip/udp address to a TIPC media address */
 110 static void tipc_udp_media_addr_set(struct tipc_media_addr *addr,
 111                                     struct udp_media_addr *ua)
 112 {
 113         memset(addr, 0, sizeof(struct tipc_media_addr));
 114         addr->media_id = TIPC_MEDIA_TYPE_UDP;
 115         memcpy(addr->value, ua, sizeof(struct udp_media_addr));
 116
 117         if (tipc_udp_is_mcast_addr(ua))
 118                 addr->broadcast = TIPC_BROADCAST_SUPPORT;
 119 }
 120
 121 /* tipc_udp_addr2str - convert ip/udp address to string */
 122 static int tipc_udp_addr2str(struct tipc_media_addr *a, char *buf, int size)
 123 {
 124         struct udp_media_addr *ua = (struct udp_media_addr *)&a->value;
 125
 126         if (ntohs(ua->proto) == ETH_P_IP)
 127                 snprintf(buf, size, "%pI4:%u", &ua->ipv4, ntohs(ua->port));
 128         else if (ntohs(ua->proto) == ETH_P_IPV6)
 129                 snprintf(buf, size, "%pI6:%u", &ua->ipv6, ntohs(ua->port));
 130         else
 131                 pr_err("Invalid UDP media address\n");
 132         return 0;
 133 }
 134
 135 /* tipc_udp_msg2addr - extract an ip/udp address from a TIPC ndisc message */
 136 static int tipc_udp_msg2addr(struct tipc_bearer *b, struct tipc_media_addr *a,
 137                              char *msg)
 138 {
 139         struct udp_media_addr *ua;
 140
 141         ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
 142         if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
 143                 return -EINVAL;
 144         tipc_udp_media_addr_set(a, ua);
 145         return 0;
 146 }
 147
 148 /* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
 149 static int tipc_udp_addr2msg(char *msg, struct tipc_media_addr *a)
 150 {
 151         memset(msg, 0, TIPC_MEDIA_INFO_SIZE);
 152         msg[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_UDP;
 153         memcpy(msg + TIPC_MEDIA_ADDR_OFFSET, a->value,
 154                sizeof(struct udp_media_addr));
 155         return 0;
 156 }
 157
 158 /* tipc_send_msg - enqueue a send request */
 159 static int tipc_udp_xmit(struct net *net, struct sk_buff *skb,
 160                          struct udp_bearer *ub, struct udp_media_addr *src,
 161                          struct udp_media_addr *dst)
 162 {
 163         int ttl, err = 0;
 164         struct rtable *rt;
 165
 166         if (dst->proto == htons(ETH_P_IP)) {
 167                 struct flowi4 fl = {
 168                         .daddr = dst->ipv4.s_addr,
 169                         .saddr = src->ipv4.s_addr,
 170                         .flowi4_mark = skb->mark,
 171                         .flowi4_proto = IPPROTO_UDP
 172                 };
 173                 rt = ip_route_output_key(net, &fl);
 174                 if (IS_ERR(rt)) {
 175                         err = PTR_ERR(rt);
 176                         goto tx_error;
 177                 }
 178
 179                 ttl = ip4_dst_hoplimit(&rt->dst);
 180                 udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
 181                                     dst->ipv4.s_addr, 0, ttl, 0, src->port,
 182                                     dst->port, false, true);
 183 #if IS_ENABLED(CONFIG_IPV6)
 184         } else {
 185                 struct dst_entry *ndst;
 186                 struct flowi6 fl6 = {
 187                         .flowi6_oif = ub->ifindex,
 188                         .daddr = dst->ipv6,
 189                         .saddr = src->ipv6,
 190                         .flowi6_proto = IPPROTO_UDP
 191                 };
 192                 err = ipv6_stub->ipv6_dst_lookup(net, ub->ubsock->sk, &ndst,
 193                                                  &fl6);
 194                 if (err)
 195                         goto tx_error;
 196                 ttl = ip6_dst_hoplimit(ndst);
 197                 err = udp_tunnel6_xmit_skb(ndst, ub->ubsock->sk, skb, NULL,
 198                                            &src->ipv6, &dst->ipv6, 0, ttl, 0,
 199                                            src->port, dst->port, false);
 200 #endif
 201         }
 202         return err;
 203
 204 tx_error:
 205         kfree_skb(skb);
 206         return err;
 207 }
 208
 209 static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
 210                              struct tipc_bearer *b,
 211                              struct tipc_media_addr *addr)
 212 {
 213         struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
 214         struct udp_media_addr *dst = (struct udp_media_addr *)&addr->value;
 215         struct udp_replicast *rcast;
 216         struct udp_bearer *ub;
 217         int err = 0;
 218
 219         if (skb_headroom(skb) < UDP_MIN_HEADROOM) {
 220                 err = pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC);
 221                 if (err)
 222                         goto out;
 223         }
 224
 225         skb_set_inner_protocol(skb, htons(ETH_P_TIPC));
 226         ub = rcu_dereference_rtnl(b->media_ptr);
 227         if (!ub) {
 228                 err = -ENODEV;
 229                 goto out;
 230         }
 231
 232         if (addr->broadcast != TIPC_REPLICAST_SUPPORT)
 233                 return tipc_udp_xmit(net, skb, ub, src, dst);
 234
 235         /* Replicast, send an skb to each configured IP address */
 236         list_for_each_entry_rcu(rcast, &ub->rcast.list, list) {
 237                 struct sk_buff *_skb;
 238
 239                 _skb = pskb_copy(skb, GFP_ATOMIC);
 240                 if (!_skb) {
 241                         err = -ENOMEM;
 242                         goto out;
 243                 }
 244
 245                 err = tipc_udp_xmit(net, _skb, ub, src, &rcast->addr);
 246                 if (err)
 247                         goto out;
 248         }
 249         err = 0;
 250 out:
 251         kfree_skb(skb);
 252         return err;
 253 }
 254
 255 static bool tipc_udp_is_known_peer(struct tipc_bearer *b,
 256                                    struct udp_media_addr *addr)
 257 {
 258         struct udp_replicast *rcast, *tmp;
 259         struct udp_bearer *ub;
 260
 261         ub = rcu_dereference_rtnl(b->media_ptr);
 262         if (!ub) {
 263                 pr_err_ratelimited("UDP bearer instance not found\n");
 264                 return false;
 265         }
 266
 267         list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
 268                 if (!memcmp(&rcast->addr, addr, sizeof(struct udp_media_addr)))
 269                         return true;
 270         }
 271
 272         return false;
 273 }
 274
 275 static int tipc_udp_rcast_add(struct tipc_bearer *b,
 276                               struct udp_media_addr *addr)
 277 {
 278         struct udp_replicast *rcast;
 279         struct udp_bearer *ub;
 280
 281         ub = rcu_dereference_rtnl(b->media_ptr);
 282         if (!ub)
 283                 return -ENODEV;
 284
 285         rcast = kmalloc(sizeof(*rcast), GFP_ATOMIC);
 286         if (!rcast)
 287                 return -ENOMEM;
 288
 289         memcpy(&rcast->addr, addr, sizeof(struct udp_media_addr));
 290
 291         if (ntohs(addr->proto) == ETH_P_IP)
 292                 pr_info("New replicast peer: %pI4\n", &rcast->addr.ipv4);
 293 #if IS_ENABLED(CONFIG_IPV6)
 294         else if (ntohs(addr->proto) == ETH_P_IPV6)
 295                 pr_info("New replicast peer: %pI6\n", &rcast->addr.ipv6);
 296 #endif
 297         b->bcast_addr.broadcast = TIPC_REPLICAST_SUPPORT;
 298         list_add_rcu(&rcast->list, &ub->rcast.list);
 299         return 0;
 300 }
 301
 302 static int tipc_udp_rcast_disc(struct tipc_bearer *b, struct sk_buff *skb)
 303 {
 304         struct udp_media_addr src = {0};
 305         struct udp_media_addr *dst;
 306
 307         dst = (struct udp_media_addr *)&b->bcast_addr.value;
 308         if (tipc_udp_is_mcast_addr(dst))
 309                 return 0;
 310
 311         src.port = udp_hdr(skb)->source;
 312
 313         if (ip_hdr(skb)->version == 4) {
 314                 struct iphdr *iphdr = ip_hdr(skb);
 315
 316                 src.proto = htons(ETH_P_IP);
 317                 src.ipv4.s_addr = iphdr->saddr;
 318                 if (ipv4_is_multicast(iphdr->daddr))
 319                         return 0;
 320 #if IS_ENABLED(CONFIG_IPV6)
 321         } else if (ip_hdr(skb)->version == 6) {
 322                 struct ipv6hdr *iphdr = ipv6_hdr(skb);
 323
 324                 src.proto = htons(ETH_P_IPV6);
 325                 src.ipv6 = iphdr->saddr;
 326                 if (ipv6_addr_is_multicast(&iphdr->daddr))
 327                         return 0;
 328 #endif
 329         } else {
 330                 return 0;
 331         }
 332
 333         if (likely(tipc_udp_is_known_peer(b, &src)))
 334                 return 0;
 335
 336         return tipc_udp_rcast_add(b, &src);
 337 }
 338
 339 /* tipc_udp_recv - read data from bearer socket */
 340 static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
 341 {
 342         struct udp_bearer *ub;
 343         struct tipc_bearer *b;
 344         struct tipc_msg *hdr;
 345         int err;
 346
 347         ub = rcu_dereference_sk_user_data(sk);
 348         if (!ub) {
 349                 pr_err_ratelimited("Failed to get UDP bearer reference");
 350                 goto out;
 351         }
 352         skb_pull(skb, sizeof(struct udphdr));
 353         hdr = buf_msg(skb);
 354
 355         b = rcu_dereference(ub->bearer);
 356         if (!b)
 357                 goto out;
 358
 359         if (b && test_bit(0, &b->up)) {
 360                 tipc_rcv(sock_net(sk), skb, b);
 361                 return 0;
 362         }
 363
 364         if (unlikely(msg_user(hdr) == LINK_CONFIG)) {
 365                 err = tipc_udp_rcast_disc(b, skb);
 366                 if (err)
 367                         goto out;
 368         }
 369
 370 out:
 371         kfree_skb(skb);
 372         return 0;
 373 }
 374
 375 static int enable_mcast(struct udp_bearer *ub, struct udp_media_addr *remote)
 376 {
 377         int err = 0;
 378         struct ip_mreqn mreqn;
 379         struct sock *sk = ub->ubsock->sk;
 380
 381         if (ntohs(remote->proto) == ETH_P_IP) {
 382                 mreqn.imr_multiaddr = remote->ipv4;
 383                 mreqn.imr_ifindex = ub->ifindex;
 384                 err = ip_mc_join_group(sk, &mreqn);
 385 #if IS_ENABLED(CONFIG_IPV6)
 386         } else {
 387                 err = ipv6_stub->ipv6_sock_mc_join(sk, ub->ifindex,
 388                                                    &remote->ipv6);
 389 #endif
 390         }
 391         return err;
 392 }
 393
 394 static int __tipc_nl_add_udp_addr(struct sk_buff *skb,
 395                                   struct udp_media_addr *addr, int nla_t)
 396 {
 397         if (ntohs(addr->proto) == ETH_P_IP) {
 398                 struct sockaddr_in ip4;
 399
 400                 memset(&ip4, 0, sizeof(ip4));
 401                 ip4.sin_family = AF_INET;
 402                 ip4.sin_port = addr->port;
 403                 ip4.sin_addr.s_addr = addr->ipv4.s_addr;
 404                 if (nla_put(skb, nla_t, sizeof(ip4), &ip4))
 405                         return -EMSGSIZE;
 406
 407 #if IS_ENABLED(CONFIG_IPV6)
 408         } else if (ntohs(addr->proto) == ETH_P_IPV6) {
 409                 struct sockaddr_in6 ip6;
 410
 411                 memset(&ip6, 0, sizeof(ip6));
 412                 ip6.sin6_family = AF_INET6;
 413                 ip6.sin6_port  = addr->port;
 414                 memcpy(&ip6.sin6_addr, &addr->ipv6, sizeof(struct in6_addr));
 415                 if (nla_put(skb, nla_t, sizeof(ip6), &ip6))
 416                         return -EMSGSIZE;
 417 #endif
 418         }
 419
 420         return 0;
 421 }
 422
 423 int tipc_udp_nl_dump_remoteip(struct sk_buff *skb, struct netlink_callback *cb)
 424 {
 425         u32 bid = cb->args[0];
 426         u32 skip_cnt = cb->args[1];
 427         u32 portid = NETLINK_CB(cb->skb).portid;
 428         struct udp_replicast *rcast, *tmp;
 429         struct tipc_bearer *b;
 430         struct udp_bearer *ub;
 431         void *hdr;
 432         int err;
 433         int i;
 434
 435         if (!bid && !skip_cnt) {
 436                 struct net *net = sock_net(skb->sk);
 437                 struct nlattr *battrs[TIPC_NLA_BEARER_MAX + 1];
 438                 struct nlattr **attrs;
 439                 char *bname;
 440
 441                 err = tipc_nlmsg_parse(cb->nlh, &attrs);
 442                 if (err)
 443                         return err;
 444
 445                 if (!attrs[TIPC_NLA_BEARER])
 446                         return -EINVAL;
 447
 448                 err = nla_parse_nested_deprecated(battrs, TIPC_NLA_BEARER_MAX,
 449                                                   attrs[TIPC_NLA_BEARER],
 450                                                   tipc_nl_bearer_policy, NULL);
 451                 if (err)
 452                         return err;
 453
 454                 if (!battrs[TIPC_NLA_BEARER_NAME])
 455                         return -EINVAL;
 456
 457                 bname = nla_data(battrs[TIPC_NLA_BEARER_NAME]);
 458
 459                 rtnl_lock();
 460                 b = tipc_bearer_find(net, bname);
 461                 if (!b) {
 462                         rtnl_unlock();
 463                         return -EINVAL;
 464                 }
 465                 bid = b->identity;
 466         } else {
 467                 struct net *net = sock_net(skb->sk);
 468                 struct tipc_net *tn = net_generic(net, tipc_net_id);
 469
 470                 rtnl_lock();
 471                 b = rtnl_dereference(tn->bearer_list[bid]);
 472                 if (!b) {
 473                         rtnl_unlock();
 474                         return -EINVAL;
 475                 }
 476         }
 477
 478         ub = rcu_dereference_rtnl(b->media_ptr);
 479         if (!ub) {
 480                 rtnl_unlock();
 481                 return -EINVAL;
 482         }
 483
 484         i = 0;
 485         list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
 486                 if (i < skip_cnt)
 487                         goto count;
 488
 489                 hdr = genlmsg_put(skb, portid, cb->nlh->nlmsg_seq,
 490                                   &tipc_genl_family, NLM_F_MULTI,
 491                                   TIPC_NL_BEARER_GET);
 492                 if (!hdr)
 493                         goto done;
 494
 495                 err = __tipc_nl_add_udp_addr(skb, &rcast->addr,
 496                                              TIPC_NLA_UDP_REMOTE);
 497                 if (err) {
 498                         genlmsg_cancel(skb, hdr);
 499                         goto done;
 500                 }
 501                 genlmsg_end(skb, hdr);
 502 count:
 503                 i++;
 504         }
 505 done:
 506         rtnl_unlock();
 507         cb->args[0] = bid;
 508         cb->args[1] = i;
 509
 510         return skb->len;
 511 }
 512
 513 int tipc_udp_nl_add_bearer_data(struct tipc_nl_msg *msg, struct tipc_bearer *b)
 514 {
 515         struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
 516         struct udp_media_addr *dst;
 517         struct udp_bearer *ub;
 518         struct nlattr *nest;
 519
 520         ub = rcu_dereference_rtnl(b->media_ptr);
 521         if (!ub)
 522                 return -ENODEV;
 523
 524         nest = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER_UDP_OPTS);
 525         if (!nest)
 526                 goto msg_full;
 527
 528         if (__tipc_nl_add_udp_addr(msg->skb, src, TIPC_NLA_UDP_LOCAL))
 529                 goto msg_full;
 530
 531         dst = (struct udp_media_addr *)&b->bcast_addr.value;
 532         if (__tipc_nl_add_udp_addr(msg->skb, dst, TIPC_NLA_UDP_REMOTE))
 533                 goto msg_full;
 534
 535         if (!list_empty(&ub->rcast.list)) {
 536                 if (nla_put_flag(msg->skb, TIPC_NLA_UDP_MULTI_REMOTEIP))
 537                         goto msg_full;
 538         }
 539
 540         nla_nest_end(msg->skb, nest);
 541         return 0;
 542 msg_full:
 543         nla_nest_cancel(msg->skb, nest);
 544         return -EMSGSIZE;
 545 }
 546
 547 /**
 548  * tipc_parse_udp_addr - build udp media address from netlink data
 549  * @nlattr:     netlink attribute containing sockaddr storage aligned address
 550  * @addr:       tipc media address to fill with address, port and protocol type
 551  * @scope_id:   IPv6 scope id pointer, not NULL indicates it's required
 552  */
 553
 554 static int tipc_parse_udp_addr(struct nlattr *nla, struct udp_media_addr *addr,
 555                                u32 *scope_id)
 556 {
 557         struct sockaddr_storage sa;
 558
 559         nla_memcpy(&sa, nla, sizeof(sa));
 560         if (sa.ss_family == AF_INET) {
 561                 struct sockaddr_in *ip4 = (struct sockaddr_in *)&sa;
 562
 563                 addr->proto = htons(ETH_P_IP);
 564                 addr->port = ip4->sin_port;
 565                 addr->ipv4.s_addr = ip4->sin_addr.s_addr;
 566                 return 0;
 567
 568 #if IS_ENABLED(CONFIG_IPV6)
 569         } else if (sa.ss_family == AF_INET6) {
 570                 struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)&sa;
 571
 572                 addr->proto = htons(ETH_P_IPV6);
 573                 addr->port = ip6->sin6_port;
 574                 memcpy(&addr->ipv6, &ip6->sin6_addr, sizeof(struct in6_addr));
 575
 576                 /* Scope ID is only interesting for local addresses */
 577                 if (scope_id) {
 578                         int atype;
 579
 580                         atype = ipv6_addr_type(&ip6->sin6_addr);
 581                         if (__ipv6_addr_needs_scope_id(atype) &&
 582                             !ip6->sin6_scope_id) {
 583                                 return -EINVAL;
 584                         }
 585
 586                         *scope_id = ip6->sin6_scope_id ? : 0;
 587                 }
 588
 589                 return 0;
 590 #endif
 591         }
 592         return -EADDRNOTAVAIL;
 593 }
 594
 595 int tipc_udp_nl_bearer_add(struct tipc_bearer *b, struct nlattr *attr)
 596 {
 597         int err;
 598         struct udp_media_addr addr = {0};
 599         struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
 600         struct udp_media_addr *dst;
 601
 602         if (nla_parse_nested_deprecated(opts, TIPC_NLA_UDP_MAX, attr, tipc_nl_udp_policy, NULL))
 603                 return -EINVAL;
 604
 605         if (!opts[TIPC_NLA_UDP_REMOTE])
 606                 return -EINVAL;
 607
 608         err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &addr, NULL);
 609         if (err)
 610                 return err;
 611
 612         dst = (struct udp_media_addr *)&b->bcast_addr.value;
 613         if (tipc_udp_is_mcast_addr(dst)) {
 614                 pr_err("Can't add remote ip to TIPC UDP multicast bearer\n");
 615                 return -EINVAL;
 616         }
 617
 618         if (tipc_udp_is_known_peer(b, &addr))
 619                 return 0;
 620
 621         return tipc_udp_rcast_add(b, &addr);
 622 }
 623
 624 /**
 625  * tipc_udp_enable - callback to create a new udp bearer instance
 626  * @net:        network namespace
 627  * @b:          pointer to generic tipc_bearer
 628  * @attrs:      netlink bearer configuration
 629  *
 630  * validate the bearer parameters and initialize the udp bearer
 631  * rtnl_lock should be held
 632  */
 633 static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
 634                            struct nlattr *attrs[])
 635 {
 636         int err = -EINVAL;
 637         struct udp_bearer *ub;
 638         struct udp_media_addr remote = {0};
 639         struct udp_media_addr local = {0};
 640         struct udp_port_cfg udp_conf = {0};
 641         struct udp_tunnel_sock_cfg tuncfg = {NULL};
 642         struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
 643         u8 node_id[NODE_ID_LEN] = {0,};
 644         int rmcast = 0;
 645
 646         ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
 647         if (!ub)
 648                 return -ENOMEM;
 649
 650         INIT_LIST_HEAD(&ub->rcast.list);
 651
 652         if (!attrs[TIPC_NLA_BEARER_UDP_OPTS])
 653                 goto err;
 654
 655         if (nla_parse_nested_deprecated(opts, TIPC_NLA_UDP_MAX, attrs[TIPC_NLA_BEARER_UDP_OPTS], tipc_nl_udp_policy, NULL))
 656                 goto err;
 657
 658         if (!opts[TIPC_NLA_UDP_LOCAL] || !opts[TIPC_NLA_UDP_REMOTE]) {
 659                 pr_err("Invalid UDP bearer configuration");
 660                 err = -EINVAL;
 661                 goto err;
 662         }
 663
 664         err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_LOCAL], &local,
 665                                   &ub->ifindex);
 666         if (err)
 667                 goto err;
 668
 669         err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &remote, NULL);
 670         if (err)
 671                 goto err;
 672
 673         if (remote.proto != local.proto) {
 674                 err = -EINVAL;
 675                 goto err;
 676         }
 677
 678         /* Checking remote ip address */
 679         rmcast = tipc_udp_is_mcast_addr(&remote);
 680
 681         /* Autoconfigure own node identity if needed */
 682         if (!tipc_own_id(net)) {
 683                 memcpy(node_id, local.ipv6.in6_u.u6_addr8, 16);
 684                 tipc_net_init(net, node_id, 0);
 685         }
 686         if (!tipc_own_id(net)) {
 687                 pr_warn("Failed to set node id, please configure manually\n");
 688                 err = -EINVAL;
 689                 goto err;
 690         }
 691
 692         b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
 693         b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
 694         rcu_assign_pointer(b->media_ptr, ub);
 695         rcu_assign_pointer(ub->bearer, b);
 696         tipc_udp_media_addr_set(&b->addr, &local);
 697         if (local.proto == htons(ETH_P_IP)) {
 698                 struct net_device *dev;
 699
 700                 dev = __ip_dev_find(net, local.ipv4.s_addr, false);
 701                 if (!dev) {
 702                         err = -ENODEV;
 703                         goto err;
 704                 }
 705                 udp_conf.family = AF_INET;
 706
 707                 /* Switch to use ANY to receive packets from group */
 708                 if (rmcast)
 709                         udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
 710                 else
 711                         udp_conf.local_ip.s_addr = local.ipv4.s_addr;
 712                 udp_conf.use_udp_checksums = false;
 713                 ub->ifindex = dev->ifindex;
 714                 if (tipc_mtu_bad(dev, sizeof(struct iphdr) +
 715                                       sizeof(struct udphdr))) {
 716                         err = -EINVAL;
 717                         goto err;
 718                 }
 719                 b->mtu = b->media->mtu;
 720 #if IS_ENABLED(CONFIG_IPV6)
 721         } else if (local.proto == htons(ETH_P_IPV6)) {
 722                 udp_conf.family = AF_INET6;
 723                 udp_conf.use_udp6_tx_checksums = true;
 724                 udp_conf.use_udp6_rx_checksums = true;
 725                 if (rmcast)
 726                         udp_conf.local_ip6 = in6addr_any;
 727                 else
 728                         udp_conf.local_ip6 = local.ipv6;
 729                 b->mtu = 1280;
 730 #endif
 731         } else {
 732                 err = -EAFNOSUPPORT;
 733                 goto err;
 734         }
 735         udp_conf.local_udp_port = local.port;
 736         err = udp_sock_create(net, &udp_conf, &ub->ubsock);
 737         if (err)
 738                 goto err;
 739         tuncfg.sk_user_data = ub;
 740         tuncfg.encap_type = 1;
 741         tuncfg.encap_rcv = tipc_udp_recv;
 742         tuncfg.encap_destroy = NULL;
 743         setup_udp_tunnel_sock(net, ub->ubsock, &tuncfg);
 744
 745         /**
 746          * The bcast media address port is used for all peers and the ip
 747          * is used if it's a multicast address.
 748          */
 749         memcpy(&b->bcast_addr.value, &remote, sizeof(remote));
 750         if (rmcast)
 751                 err = enable_mcast(ub, &remote);
 752         else
 753                 err = tipc_udp_rcast_add(b, &remote);
 754         if (err)
 755                 goto err;
 756
 757         return 0;
 758 err:
 759         if (ub->ubsock)
 760                 udp_tunnel_sock_release(ub->ubsock);
 761         kfree(ub);
 762         return err;
 763 }
 764
 765 /* cleanup_bearer - break the socket/bearer association */
 766 static void cleanup_bearer(struct work_struct *work)
 767 {
 768         struct udp_bearer *ub = container_of(work, struct udp_bearer, work);
 769         struct udp_replicast *rcast, *tmp;
 770
 771         list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
 772                 list_del_rcu(&rcast->list);
 773                 kfree_rcu(rcast, rcu);
 774         }
 775
 776         if (ub->ubsock)
 777                 udp_tunnel_sock_release(ub->ubsock);
 778         synchronize_net();
 779         kfree(ub);
 780 }
 781
 782 /* tipc_udp_disable - detach bearer from socket */
 783 static void tipc_udp_disable(struct tipc_bearer *b)
 784 {
 785         struct udp_bearer *ub;
 786
 787         ub = rcu_dereference_rtnl(b->media_ptr);
 788         if (!ub) {
 789                 pr_err("UDP bearer instance not found\n");
 790                 return;
 791         }
 792         if (ub->ubsock)
 793                 sock_set_flag(ub->ubsock->sk, SOCK_DEAD);
 794         RCU_INIT_POINTER(ub->bearer, NULL);
 795
 796         /* sock_release need to be done outside of rtnl lock */
 797         INIT_WORK(&ub->work, cleanup_bearer);
 798         schedule_work(&ub->work);
 799 }
 800
 801 struct tipc_media udp_media_info = {
 802         .send_msg       = tipc_udp_send_msg,
 803         .enable_media   = tipc_udp_enable,
 804         .disable_media  = tipc_udp_disable,
 805         .addr2str       = tipc_udp_addr2str,
 806         .addr2msg       = tipc_udp_addr2msg,
 807         .msg2addr       = tipc_udp_msg2addr,
 808         .priority       = TIPC_DEF_LINK_PRI,
 809         .tolerance      = TIPC_DEF_LINK_TOL,
 810         .window         = TIPC_DEF_LINK_WIN,
 811         .mtu            = TIPC_DEF_LINK_UDP_MTU,
 812         .type_id        = TIPC_MEDIA_TYPE_UDP,
 813         .hwaddr_len     = 0,
 814         .name           = "udp"
 815 };