linux/net/tipc/udp_media.c
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   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#include "udp_media.h"
  56
  57/* IANA assigned UDP port */
  58#define UDP_PORT_DEFAULT        6118
  59
  60#define UDP_MIN_HEADROOM        48
  61
  62/**
  63 * struct udp_media_addr - IP/UDP addressing information
  64 *
  65 * This is the bearer level originating address used in neighbor discovery
  66 * messages, and all fields should be in network byte order
  67 *
  68 * @proto: Ethernet protocol in use
  69 * @port: port being used
  70 * @ipv4: IPv4 address of neighbor
  71 * @ipv6: IPv6 address of neighbor
  72 */
  73struct udp_media_addr {
  74        __be16  proto;
  75        __be16  port;
  76        union {
  77                struct in_addr ipv4;
  78                struct in6_addr ipv6;
  79        };
  80};
  81
  82/* struct udp_replicast - container for UDP remote addresses */
  83struct udp_replicast {
  84        struct udp_media_addr addr;
  85        struct dst_cache dst_cache;
  86        struct rcu_head rcu;
  87        struct list_head list;
  88};
  89
  90/**
  91 * struct udp_bearer - ip/udp bearer data structure
  92 * @bearer:     associated generic tipc bearer
  93 * @ubsock:     bearer associated socket
  94 * @ifindex:    local address scope
  95 * @work:       used to schedule deferred work on a bearer
  96 * @rcast:      associated udp_replicast container
  97 */
  98struct udp_bearer {
  99        struct tipc_bearer __rcu *bearer;
 100        struct socket *ubsock;
 101        u32 ifindex;
 102        struct work_struct work;
 103        struct udp_replicast rcast;
 104};
 105
 106static int tipc_udp_is_mcast_addr(struct udp_media_addr *addr)
 107{
 108        if (ntohs(addr->proto) == ETH_P_IP)
 109                return ipv4_is_multicast(addr->ipv4.s_addr);
 110#if IS_ENABLED(CONFIG_IPV6)
 111        else
 112                return ipv6_addr_is_multicast(&addr->ipv6);
 113#endif
 114        return 0;
 115}
 116
 117/* udp_media_addr_set - convert a ip/udp address to a TIPC media address */
 118static void tipc_udp_media_addr_set(struct tipc_media_addr *addr,
 119                                    struct udp_media_addr *ua)
 120{
 121        memset(addr, 0, sizeof(struct tipc_media_addr));
 122        addr->media_id = TIPC_MEDIA_TYPE_UDP;
 123        memcpy(addr->value, ua, sizeof(struct udp_media_addr));
 124
 125        if (tipc_udp_is_mcast_addr(ua))
 126                addr->broadcast = TIPC_BROADCAST_SUPPORT;
 127}
 128
 129/* tipc_udp_addr2str - convert ip/udp address to string */
 130static int tipc_udp_addr2str(struct tipc_media_addr *a, char *buf, int size)
 131{
 132        struct udp_media_addr *ua = (struct udp_media_addr *)&a->value;
 133
 134        if (ntohs(ua->proto) == ETH_P_IP)
 135                snprintf(buf, size, "%pI4:%u", &ua->ipv4, ntohs(ua->port));
 136        else if (ntohs(ua->proto) == ETH_P_IPV6)
 137                snprintf(buf, size, "%pI6:%u", &ua->ipv6, ntohs(ua->port));
 138        else
 139                pr_err("Invalid UDP media address\n");
 140        return 0;
 141}
 142
 143/* tipc_udp_msg2addr - extract an ip/udp address from a TIPC ndisc message */
 144static int tipc_udp_msg2addr(struct tipc_bearer *b, struct tipc_media_addr *a,
 145                             char *msg)
 146{
 147        struct udp_media_addr *ua;
 148
 149        ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
 150        if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
 151                return -EINVAL;
 152        tipc_udp_media_addr_set(a, ua);
 153        return 0;
 154}
 155
 156/* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
 157static int tipc_udp_addr2msg(char *msg, struct tipc_media_addr *a)
 158{
 159        memset(msg, 0, TIPC_MEDIA_INFO_SIZE);
 160        msg[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_UDP;
 161        memcpy(msg + TIPC_MEDIA_ADDR_OFFSET, a->value,
 162               sizeof(struct udp_media_addr));
 163        return 0;
 164}
 165
 166/* tipc_send_msg - enqueue a send request */
 167static int tipc_udp_xmit(struct net *net, struct sk_buff *skb,
 168                         struct udp_bearer *ub, struct udp_media_addr *src,
 169                         struct udp_media_addr *dst, struct dst_cache *cache)
 170{
 171        struct dst_entry *ndst;
 172        int ttl, err = 0;
 173
 174        local_bh_disable();
 175        ndst = dst_cache_get(cache);
 176        if (dst->proto == htons(ETH_P_IP)) {
 177                struct rtable *rt = (struct rtable *)ndst;
 178
 179                if (!rt) {
 180                        struct flowi4 fl = {
 181                                .daddr = dst->ipv4.s_addr,
 182                                .saddr = src->ipv4.s_addr,
 183                                .flowi4_mark = skb->mark,
 184                                .flowi4_proto = IPPROTO_UDP
 185                        };
 186                        rt = ip_route_output_key(net, &fl);
 187                        if (IS_ERR(rt)) {
 188                                err = PTR_ERR(rt);
 189                                goto tx_error;
 190                        }
 191                        dst_cache_set_ip4(cache, &rt->dst, fl.saddr);
 192                }
 193
 194                ttl = ip4_dst_hoplimit(&rt->dst);
 195                udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
 196                                    dst->ipv4.s_addr, 0, ttl, 0, src->port,
 197                                    dst->port, false, true);
 198#if IS_ENABLED(CONFIG_IPV6)
 199        } else {
 200                if (!ndst) {
 201                        struct flowi6 fl6 = {
 202                                .flowi6_oif = ub->ifindex,
 203                                .daddr = dst->ipv6,
 204                                .saddr = src->ipv6,
 205                                .flowi6_proto = IPPROTO_UDP
 206                        };
 207                        ndst = ipv6_stub->ipv6_dst_lookup_flow(net,
 208                                                               ub->ubsock->sk,
 209                                                               &fl6, NULL);
 210                        if (IS_ERR(ndst)) {
 211                                err = PTR_ERR(ndst);
 212                                goto tx_error;
 213                        }
 214                        dst_cache_set_ip6(cache, ndst, &fl6.saddr);
 215                }
 216                ttl = ip6_dst_hoplimit(ndst);
 217                err = udp_tunnel6_xmit_skb(ndst, ub->ubsock->sk, skb, NULL,
 218                                           &src->ipv6, &dst->ipv6, 0, ttl, 0,
 219                                           src->port, dst->port, false);
 220#endif
 221        }
 222        local_bh_enable();
 223        return err;
 224
 225tx_error:
 226        local_bh_enable();
 227        kfree_skb(skb);
 228        return err;
 229}
 230
 231static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
 232                             struct tipc_bearer *b,
 233                             struct tipc_media_addr *addr)
 234{
 235        struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
 236        struct udp_media_addr *dst = (struct udp_media_addr *)&addr->value;
 237        struct udp_replicast *rcast;
 238        struct udp_bearer *ub;
 239        int err = 0;
 240
 241        if (skb_headroom(skb) < UDP_MIN_HEADROOM) {
 242                err = pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC);
 243                if (err)
 244                        goto out;
 245        }
 246
 247        skb_set_inner_protocol(skb, htons(ETH_P_TIPC));
 248        ub = rcu_dereference(b->media_ptr);
 249        if (!ub) {
 250                err = -ENODEV;
 251                goto out;
 252        }
 253
 254        if (addr->broadcast != TIPC_REPLICAST_SUPPORT)
 255                return tipc_udp_xmit(net, skb, ub, src, dst,
 256                                     &ub->rcast.dst_cache);
 257
 258        /* Replicast, send an skb to each configured IP address */
 259        list_for_each_entry_rcu(rcast, &ub->rcast.list, list) {
 260                struct sk_buff *_skb;
 261
 262                _skb = pskb_copy(skb, GFP_ATOMIC);
 263                if (!_skb) {
 264                        err = -ENOMEM;
 265                        goto out;
 266                }
 267
 268                err = tipc_udp_xmit(net, _skb, ub, src, &rcast->addr,
 269                                    &rcast->dst_cache);
 270                if (err)
 271                        goto out;
 272        }
 273        err = 0;
 274out:
 275        kfree_skb(skb);
 276        return err;
 277}
 278
 279static bool tipc_udp_is_known_peer(struct tipc_bearer *b,
 280                                   struct udp_media_addr *addr)
 281{
 282        struct udp_replicast *rcast, *tmp;
 283        struct udp_bearer *ub;
 284
 285        ub = rcu_dereference_rtnl(b->media_ptr);
 286        if (!ub) {
 287                pr_err_ratelimited("UDP bearer instance not found\n");
 288                return false;
 289        }
 290
 291        list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
 292                if (!memcmp(&rcast->addr, addr, sizeof(struct udp_media_addr)))
 293                        return true;
 294        }
 295
 296        return false;
 297}
 298
 299static int tipc_udp_rcast_add(struct tipc_bearer *b,
 300                              struct udp_media_addr *addr)
 301{
 302        struct udp_replicast *rcast;
 303        struct udp_bearer *ub;
 304
 305        ub = rcu_dereference_rtnl(b->media_ptr);
 306        if (!ub)
 307                return -ENODEV;
 308
 309        rcast = kmalloc(sizeof(*rcast), GFP_ATOMIC);
 310        if (!rcast)
 311                return -ENOMEM;
 312
 313        if (dst_cache_init(&rcast->dst_cache, GFP_ATOMIC)) {
 314                kfree(rcast);
 315                return -ENOMEM;
 316        }
 317
 318        memcpy(&rcast->addr, addr, sizeof(struct udp_media_addr));
 319
 320        if (ntohs(addr->proto) == ETH_P_IP)
 321                pr_info("New replicast peer: %pI4\n", &rcast->addr.ipv4);
 322#if IS_ENABLED(CONFIG_IPV6)
 323        else if (ntohs(addr->proto) == ETH_P_IPV6)
 324                pr_info("New replicast peer: %pI6\n", &rcast->addr.ipv6);
 325#endif
 326        b->bcast_addr.broadcast = TIPC_REPLICAST_SUPPORT;
 327        list_add_rcu(&rcast->list, &ub->rcast.list);
 328        return 0;
 329}
 330
 331static int tipc_udp_rcast_disc(struct tipc_bearer *b, struct sk_buff *skb)
 332{
 333        struct udp_media_addr src = {0};
 334        struct udp_media_addr *dst;
 335
 336        dst = (struct udp_media_addr *)&b->bcast_addr.value;
 337        if (tipc_udp_is_mcast_addr(dst))
 338                return 0;
 339
 340        src.port = udp_hdr(skb)->source;
 341
 342        if (ip_hdr(skb)->version == 4) {
 343                struct iphdr *iphdr = ip_hdr(skb);
 344
 345                src.proto = htons(ETH_P_IP);
 346                src.ipv4.s_addr = iphdr->saddr;
 347                if (ipv4_is_multicast(iphdr->daddr))
 348                        return 0;
 349#if IS_ENABLED(CONFIG_IPV6)
 350        } else if (ip_hdr(skb)->version == 6) {
 351                struct ipv6hdr *iphdr = ipv6_hdr(skb);
 352
 353                src.proto = htons(ETH_P_IPV6);
 354                src.ipv6 = iphdr->saddr;
 355                if (ipv6_addr_is_multicast(&iphdr->daddr))
 356                        return 0;
 357#endif
 358        } else {
 359                return 0;
 360        }
 361
 362        if (likely(tipc_udp_is_known_peer(b, &src)))
 363                return 0;
 364
 365        return tipc_udp_rcast_add(b, &src);
 366}
 367
 368/* tipc_udp_recv - read data from bearer socket */
 369static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
 370{
 371        struct udp_bearer *ub;
 372        struct tipc_bearer *b;
 373        struct tipc_msg *hdr;
 374        int err;
 375
 376        ub = rcu_dereference_sk_user_data(sk);
 377        if (!ub) {
 378                pr_err_ratelimited("Failed to get UDP bearer reference");
 379                goto out;
 380        }
 381        skb_pull(skb, sizeof(struct udphdr));
 382        hdr = buf_msg(skb);
 383
 384        b = rcu_dereference(ub->bearer);
 385        if (!b)
 386                goto out;
 387
 388        if (b && test_bit(0, &b->up)) {
 389                TIPC_SKB_CB(skb)->flags = 0;
 390                tipc_rcv(sock_net(sk), skb, b);
 391                return 0;
 392        }
 393
 394        if (unlikely(msg_user(hdr) == LINK_CONFIG)) {
 395                err = tipc_udp_rcast_disc(b, skb);
 396                if (err)
 397                        goto out;
 398        }
 399
 400out:
 401        kfree_skb(skb);
 402        return 0;
 403}
 404
 405static int enable_mcast(struct udp_bearer *ub, struct udp_media_addr *remote)
 406{
 407        int err = 0;
 408        struct ip_mreqn mreqn;
 409        struct sock *sk = ub->ubsock->sk;
 410
 411        if (ntohs(remote->proto) == ETH_P_IP) {
 412                mreqn.imr_multiaddr = remote->ipv4;
 413                mreqn.imr_ifindex = ub->ifindex;
 414                err = ip_mc_join_group(sk, &mreqn);
 415#if IS_ENABLED(CONFIG_IPV6)
 416        } else {
 417                lock_sock(sk);
 418                err = ipv6_stub->ipv6_sock_mc_join(sk, ub->ifindex,
 419                                                   &remote->ipv6);
 420                release_sock(sk);
 421#endif
 422        }
 423        return err;
 424}
 425
 426static int __tipc_nl_add_udp_addr(struct sk_buff *skb,
 427                                  struct udp_media_addr *addr, int nla_t)
 428{
 429        if (ntohs(addr->proto) == ETH_P_IP) {
 430                struct sockaddr_in ip4;
 431
 432                memset(&ip4, 0, sizeof(ip4));
 433                ip4.sin_family = AF_INET;
 434                ip4.sin_port = addr->port;
 435                ip4.sin_addr.s_addr = addr->ipv4.s_addr;
 436                if (nla_put(skb, nla_t, sizeof(ip4), &ip4))
 437                        return -EMSGSIZE;
 438
 439#if IS_ENABLED(CONFIG_IPV6)
 440        } else if (ntohs(addr->proto) == ETH_P_IPV6) {
 441                struct sockaddr_in6 ip6;
 442
 443                memset(&ip6, 0, sizeof(ip6));
 444                ip6.sin6_family = AF_INET6;
 445                ip6.sin6_port  = addr->port;
 446                memcpy(&ip6.sin6_addr, &addr->ipv6, sizeof(struct in6_addr));
 447                if (nla_put(skb, nla_t, sizeof(ip6), &ip6))
 448                        return -EMSGSIZE;
 449#endif
 450        }
 451
 452        return 0;
 453}
 454
 455int tipc_udp_nl_dump_remoteip(struct sk_buff *skb, struct netlink_callback *cb)
 456{
 457        u32 bid = cb->args[0];
 458        u32 skip_cnt = cb->args[1];
 459        u32 portid = NETLINK_CB(cb->skb).portid;
 460        struct udp_replicast *rcast, *tmp;
 461        struct tipc_bearer *b;
 462        struct udp_bearer *ub;
 463        void *hdr;
 464        int err;
 465        int i;
 466
 467        if (!bid && !skip_cnt) {
 468                struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
 469                struct net *net = sock_net(skb->sk);
 470                struct nlattr *battrs[TIPC_NLA_BEARER_MAX + 1];
 471                char *bname;
 472
 473                if (!attrs[TIPC_NLA_BEARER])
 474                        return -EINVAL;
 475
 476                err = nla_parse_nested_deprecated(battrs, TIPC_NLA_BEARER_MAX,
 477                                                  attrs[TIPC_NLA_BEARER],
 478                                                  tipc_nl_bearer_policy, NULL);
 479                if (err)
 480                        return err;
 481
 482                if (!battrs[TIPC_NLA_BEARER_NAME])
 483                        return -EINVAL;
 484
 485                bname = nla_data(battrs[TIPC_NLA_BEARER_NAME]);
 486
 487                rtnl_lock();
 488                b = tipc_bearer_find(net, bname);
 489                if (!b) {
 490                        rtnl_unlock();
 491                        return -EINVAL;
 492                }
 493                bid = b->identity;
 494        } else {
 495                struct net *net = sock_net(skb->sk);
 496                struct tipc_net *tn = net_generic(net, tipc_net_id);
 497
 498                rtnl_lock();
 499                b = rtnl_dereference(tn->bearer_list[bid]);
 500                if (!b) {
 501                        rtnl_unlock();
 502                        return -EINVAL;
 503                }
 504        }
 505
 506        ub = rtnl_dereference(b->media_ptr);
 507        if (!ub) {
 508                rtnl_unlock();
 509                return -EINVAL;
 510        }
 511
 512        i = 0;
 513        list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
 514                if (i < skip_cnt)
 515                        goto count;
 516
 517                hdr = genlmsg_put(skb, portid, cb->nlh->nlmsg_seq,
 518                                  &tipc_genl_family, NLM_F_MULTI,
 519                                  TIPC_NL_BEARER_GET);
 520                if (!hdr)
 521                        goto done;
 522
 523                err = __tipc_nl_add_udp_addr(skb, &rcast->addr,
 524                                             TIPC_NLA_UDP_REMOTE);
 525                if (err) {
 526                        genlmsg_cancel(skb, hdr);
 527                        goto done;
 528                }
 529                genlmsg_end(skb, hdr);
 530count:
 531                i++;
 532        }
 533done:
 534        rtnl_unlock();
 535        cb->args[0] = bid;
 536        cb->args[1] = i;
 537
 538        return skb->len;
 539}
 540
 541int tipc_udp_nl_add_bearer_data(struct tipc_nl_msg *msg, struct tipc_bearer *b)
 542{
 543        struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
 544        struct udp_media_addr *dst;
 545        struct udp_bearer *ub;
 546        struct nlattr *nest;
 547
 548        ub = rtnl_dereference(b->media_ptr);
 549        if (!ub)
 550                return -ENODEV;
 551
 552        nest = nla_nest_start_noflag(msg->skb, TIPC_NLA_BEARER_UDP_OPTS);
 553        if (!nest)
 554                goto msg_full;
 555
 556        if (__tipc_nl_add_udp_addr(msg->skb, src, TIPC_NLA_UDP_LOCAL))
 557                goto msg_full;
 558
 559        dst = (struct udp_media_addr *)&b->bcast_addr.value;
 560        if (__tipc_nl_add_udp_addr(msg->skb, dst, TIPC_NLA_UDP_REMOTE))
 561                goto msg_full;
 562
 563        if (!list_empty(&ub->rcast.list)) {
 564                if (nla_put_flag(msg->skb, TIPC_NLA_UDP_MULTI_REMOTEIP))
 565                        goto msg_full;
 566        }
 567
 568        nla_nest_end(msg->skb, nest);
 569        return 0;
 570msg_full:
 571        nla_nest_cancel(msg->skb, nest);
 572        return -EMSGSIZE;
 573}
 574
 575/**
 576 * tipc_parse_udp_addr - build udp media address from netlink data
 577 * @nla:        netlink attribute containing sockaddr storage aligned address
 578 * @addr:       tipc media address to fill with address, port and protocol type
 579 * @scope_id:   IPv6 scope id pointer, not NULL indicates it's required
 580 */
 581
 582static int tipc_parse_udp_addr(struct nlattr *nla, struct udp_media_addr *addr,
 583                               u32 *scope_id)
 584{
 585        struct sockaddr_storage sa;
 586
 587        nla_memcpy(&sa, nla, sizeof(sa));
 588        if (sa.ss_family == AF_INET) {
 589                struct sockaddr_in *ip4 = (struct sockaddr_in *)&sa;
 590
 591                addr->proto = htons(ETH_P_IP);
 592                addr->port = ip4->sin_port;
 593                addr->ipv4.s_addr = ip4->sin_addr.s_addr;
 594                return 0;
 595
 596#if IS_ENABLED(CONFIG_IPV6)
 597        } else if (sa.ss_family == AF_INET6) {
 598                struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)&sa;
 599
 600                addr->proto = htons(ETH_P_IPV6);
 601                addr->port = ip6->sin6_port;
 602                memcpy(&addr->ipv6, &ip6->sin6_addr, sizeof(struct in6_addr));
 603
 604                /* Scope ID is only interesting for local addresses */
 605                if (scope_id) {
 606                        int atype;
 607
 608                        atype = ipv6_addr_type(&ip6->sin6_addr);
 609                        if (__ipv6_addr_needs_scope_id(atype) &&
 610                            !ip6->sin6_scope_id) {
 611                                return -EINVAL;
 612                        }
 613
 614                        *scope_id = ip6->sin6_scope_id ? : 0;
 615                }
 616
 617                return 0;
 618#endif
 619        }
 620        return -EADDRNOTAVAIL;
 621}
 622
 623int tipc_udp_nl_bearer_add(struct tipc_bearer *b, struct nlattr *attr)
 624{
 625        int err;
 626        struct udp_media_addr addr = {0};
 627        struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
 628        struct udp_media_addr *dst;
 629
 630        if (nla_parse_nested_deprecated(opts, TIPC_NLA_UDP_MAX, attr, tipc_nl_udp_policy, NULL))
 631                return -EINVAL;
 632
 633        if (!opts[TIPC_NLA_UDP_REMOTE])
 634                return -EINVAL;
 635
 636        err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &addr, NULL);
 637        if (err)
 638                return err;
 639
 640        dst = (struct udp_media_addr *)&b->bcast_addr.value;
 641        if (tipc_udp_is_mcast_addr(dst)) {
 642                pr_err("Can't add remote ip to TIPC UDP multicast bearer\n");
 643                return -EINVAL;
 644        }
 645
 646        if (tipc_udp_is_known_peer(b, &addr))
 647                return 0;
 648
 649        return tipc_udp_rcast_add(b, &addr);
 650}
 651
 652/**
 653 * tipc_udp_enable - callback to create a new udp bearer instance
 654 * @net:        network namespace
 655 * @b:          pointer to generic tipc_bearer
 656 * @attrs:      netlink bearer configuration
 657 *
 658 * validate the bearer parameters and initialize the udp bearer
 659 * rtnl_lock should be held
 660 */
 661static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
 662                           struct nlattr *attrs[])
 663{
 664        int err = -EINVAL;
 665        struct udp_bearer *ub;
 666        struct udp_media_addr remote = {0};
 667        struct udp_media_addr local = {0};
 668        struct udp_port_cfg udp_conf = {0};
 669        struct udp_tunnel_sock_cfg tuncfg = {NULL};
 670        struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
 671        u8 node_id[NODE_ID_LEN] = {0,};
 672        struct net_device *dev;
 673        int rmcast = 0;
 674
 675        ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
 676        if (!ub)
 677                return -ENOMEM;
 678
 679        INIT_LIST_HEAD(&ub->rcast.list);
 680
 681        if (!attrs[TIPC_NLA_BEARER_UDP_OPTS])
 682                goto err;
 683
 684        if (nla_parse_nested_deprecated(opts, TIPC_NLA_UDP_MAX, attrs[TIPC_NLA_BEARER_UDP_OPTS], tipc_nl_udp_policy, NULL))
 685                goto err;
 686
 687        if (!opts[TIPC_NLA_UDP_LOCAL] || !opts[TIPC_NLA_UDP_REMOTE]) {
 688                pr_err("Invalid UDP bearer configuration");
 689                err = -EINVAL;
 690                goto err;
 691        }
 692
 693        err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_LOCAL], &local,
 694                                  &ub->ifindex);
 695        if (err)
 696                goto err;
 697
 698        err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &remote, NULL);
 699        if (err)
 700                goto err;
 701
 702        if (remote.proto != local.proto) {
 703                err = -EINVAL;
 704                goto err;
 705        }
 706
 707        /* Checking remote ip address */
 708        rmcast = tipc_udp_is_mcast_addr(&remote);
 709
 710        /* Autoconfigure own node identity if needed */
 711        if (!tipc_own_id(net)) {
 712                memcpy(node_id, local.ipv6.in6_u.u6_addr8, 16);
 713                tipc_net_init(net, node_id, 0);
 714        }
 715        if (!tipc_own_id(net)) {
 716                pr_warn("Failed to set node id, please configure manually\n");
 717                err = -EINVAL;
 718                goto err;
 719        }
 720
 721        b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
 722        b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
 723        rcu_assign_pointer(b->media_ptr, ub);
 724        rcu_assign_pointer(ub->bearer, b);
 725        tipc_udp_media_addr_set(&b->addr, &local);
 726        if (local.proto == htons(ETH_P_IP)) {
 727                dev = __ip_dev_find(net, local.ipv4.s_addr, false);
 728                if (!dev) {
 729                        err = -ENODEV;
 730                        goto err;
 731                }
 732                udp_conf.family = AF_INET;
 733
 734                /* Switch to use ANY to receive packets from group */
 735                if (rmcast)
 736                        udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
 737                else
 738                        udp_conf.local_ip.s_addr = local.ipv4.s_addr;
 739                udp_conf.use_udp_checksums = false;
 740                ub->ifindex = dev->ifindex;
 741                if (tipc_mtu_bad(dev, sizeof(struct iphdr) +
 742                                      sizeof(struct udphdr))) {
 743                        err = -EINVAL;
 744                        goto err;
 745                }
 746                b->mtu = b->media->mtu;
 747#if IS_ENABLED(CONFIG_IPV6)
 748        } else if (local.proto == htons(ETH_P_IPV6)) {
 749                dev = ub->ifindex ? __dev_get_by_index(net, ub->ifindex) : NULL;
 750                dev = ipv6_dev_find(net, &local.ipv6, dev);
 751                if (!dev) {
 752                        err = -ENODEV;
 753                        goto err;
 754                }
 755                udp_conf.family = AF_INET6;
 756                udp_conf.use_udp6_tx_checksums = true;
 757                udp_conf.use_udp6_rx_checksums = true;
 758                if (rmcast)
 759                        udp_conf.local_ip6 = in6addr_any;
 760                else
 761                        udp_conf.local_ip6 = local.ipv6;
 762                ub->ifindex = dev->ifindex;
 763                b->mtu = 1280;
 764#endif
 765        } else {
 766                err = -EAFNOSUPPORT;
 767                goto err;
 768        }
 769        udp_conf.local_udp_port = local.port;
 770        err = udp_sock_create(net, &udp_conf, &ub->ubsock);
 771        if (err)
 772                goto err;
 773        tuncfg.sk_user_data = ub;
 774        tuncfg.encap_type = 1;
 775        tuncfg.encap_rcv = tipc_udp_recv;
 776        tuncfg.encap_destroy = NULL;
 777        setup_udp_tunnel_sock(net, ub->ubsock, &tuncfg);
 778
 779        err = dst_cache_init(&ub->rcast.dst_cache, GFP_ATOMIC);
 780        if (err)
 781                goto free;
 782
 783        /*
 784         * The bcast media address port is used for all peers and the ip
 785         * is used if it's a multicast address.
 786         */
 787        memcpy(&b->bcast_addr.value, &remote, sizeof(remote));
 788        if (rmcast)
 789                err = enable_mcast(ub, &remote);
 790        else
 791                err = tipc_udp_rcast_add(b, &remote);
 792        if (err)
 793                goto free;
 794
 795        return 0;
 796
 797free:
 798        dst_cache_destroy(&ub->rcast.dst_cache);
 799        udp_tunnel_sock_release(ub->ubsock);
 800err:
 801        kfree(ub);
 802        return err;
 803}
 804
 805/* cleanup_bearer - break the socket/bearer association */
 806static void cleanup_bearer(struct work_struct *work)
 807{
 808        struct udp_bearer *ub = container_of(work, struct udp_bearer, work);
 809        struct udp_replicast *rcast, *tmp;
 810
 811        list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
 812                dst_cache_destroy(&rcast->dst_cache);
 813                list_del_rcu(&rcast->list);
 814                kfree_rcu(rcast, rcu);
 815        }
 816
 817        atomic_dec(&tipc_net(sock_net(ub->ubsock->sk))->wq_count);
 818        dst_cache_destroy(&ub->rcast.dst_cache);
 819        udp_tunnel_sock_release(ub->ubsock);
 820        synchronize_net();
 821        kfree(ub);
 822}
 823
 824/* tipc_udp_disable - detach bearer from socket */
 825static void tipc_udp_disable(struct tipc_bearer *b)
 826{
 827        struct udp_bearer *ub;
 828
 829        ub = rtnl_dereference(b->media_ptr);
 830        if (!ub) {
 831                pr_err("UDP bearer instance not found\n");
 832                return;
 833        }
 834        sock_set_flag(ub->ubsock->sk, SOCK_DEAD);
 835        RCU_INIT_POINTER(ub->bearer, NULL);
 836
 837        /* sock_release need to be done outside of rtnl lock */
 838        atomic_inc(&tipc_net(sock_net(ub->ubsock->sk))->wq_count);
 839        INIT_WORK(&ub->work, cleanup_bearer);
 840        schedule_work(&ub->work);
 841}
 842
 843struct tipc_media udp_media_info = {
 844        .send_msg       = tipc_udp_send_msg,
 845        .enable_media   = tipc_udp_enable,
 846        .disable_media  = tipc_udp_disable,
 847        .addr2str       = tipc_udp_addr2str,
 848        .addr2msg       = tipc_udp_addr2msg,
 849        .msg2addr       = tipc_udp_msg2addr,
 850        .priority       = TIPC_DEF_LINK_PRI,
 851        .tolerance      = TIPC_DEF_LINK_TOL,
 852        .min_win        = TIPC_DEF_LINK_WIN,
 853        .max_win        = TIPC_DEF_LINK_WIN,
 854        .mtu            = TIPC_DEF_LINK_UDP_MTU,
 855        .type_id        = TIPC_MEDIA_TYPE_UDP,
 856        .hwaddr_len     = 0,
 857        .name           = "udp"
 858};
 859