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