1 /* SCTP kernel implementation 2 * (C) Copyright IBM Corp. 2002, 2004 3 * Copyright (c) 2001 Nokia, Inc. 4 * Copyright (c) 2001 La Monte H.P. Yarroll 5 * Copyright (c) 2002-2003 Intel Corp. 6 * 7 * This file is part of the SCTP kernel implementation 8 * 9 * SCTP over IPv6. 10 * 11 * This SCTP implementation is free software; 12 * you can redistribute it and/or modify it under the terms of 13 * the GNU General Public License as published by 14 * the Free Software Foundation; either version 2, or (at your option) 15 * any later version. 16 * 17 * This SCTP implementation is distributed in the hope that it 18 * will be useful, but WITHOUT ANY WARRANTY; without even the implied 19 * ************************ 20 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 21 * See the GNU General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License 24 * along with GNU CC; see the file COPYING. If not, see 25 * <http://www.gnu.org/licenses/>. 26 * 27 * Please send any bug reports or fixes you make to the 28 * email address(es): 29 * lksctp developers <linux-sctp@vger.kernel.org> 30 * 31 * Written or modified by: 32 * Le Yanqun <yanqun.le@nokia.com> 33 * Hui Huang <hui.huang@nokia.com> 34 * La Monte H.P. Yarroll <piggy@acm.org> 35 * Sridhar Samudrala <sri@us.ibm.com> 36 * Jon Grimm <jgrimm@us.ibm.com> 37 * Ardelle Fan <ardelle.fan@intel.com> 38 * 39 * Based on: 40 * linux/net/ipv6/tcp_ipv6.c 41 */ 42 43 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 44 45 #include <linux/module.h> 46 #include <linux/errno.h> 47 #include <linux/types.h> 48 #include <linux/socket.h> 49 #include <linux/sockios.h> 50 #include <linux/net.h> 51 #include <linux/in.h> 52 #include <linux/in6.h> 53 #include <linux/netdevice.h> 54 #include <linux/init.h> 55 #include <linux/ipsec.h> 56 #include <linux/slab.h> 57 58 #include <linux/ipv6.h> 59 #include <linux/icmpv6.h> 60 #include <linux/random.h> 61 #include <linux/seq_file.h> 62 63 #include <net/protocol.h> 64 #include <net/ndisc.h> 65 #include <net/ip.h> 66 #include <net/ipv6.h> 67 #include <net/transp_v6.h> 68 #include <net/addrconf.h> 69 #include <net/ip6_route.h> 70 #include <net/inet_common.h> 71 #include <net/inet_ecn.h> 72 #include <net/sctp/sctp.h> 73 74 #include <linux/uaccess.h> 75 76 static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 77 union sctp_addr *s2); 78 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 79 __be16 port); 80 static int sctp_v6_cmp_addr(const union sctp_addr *addr1, 81 const union sctp_addr *addr2); 82 83 /* Event handler for inet6 address addition/deletion events. 84 * The sctp_local_addr_list needs to be protocted by a spin lock since 85 * multiple notifiers (say IPv4 and IPv6) may be running at the same 86 * time and thus corrupt the list. 87 * The reader side is protected with RCU. 88 */ 89 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev, 90 void *ptr) 91 { 92 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr; 93 struct sctp_sockaddr_entry *addr = NULL; 94 struct sctp_sockaddr_entry *temp; 95 struct net *net = dev_net(ifa->idev->dev); 96 int found = 0; 97 98 switch (ev) { 99 case NETDEV_UP: 100 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC); 101 if (addr) { 102 addr->a.v6.sin6_family = AF_INET6; 103 addr->a.v6.sin6_port = 0; 104 addr->a.v6.sin6_addr = ifa->addr; 105 addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex; 106 addr->valid = 1; 107 spin_lock_bh(&net->sctp.local_addr_lock); 108 list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list); 109 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW); 110 spin_unlock_bh(&net->sctp.local_addr_lock); 111 } 112 break; 113 case NETDEV_DOWN: 114 spin_lock_bh(&net->sctp.local_addr_lock); 115 list_for_each_entry_safe(addr, temp, 116 &net->sctp.local_addr_list, list) { 117 if (addr->a.sa.sa_family == AF_INET6 && 118 ipv6_addr_equal(&addr->a.v6.sin6_addr, 119 &ifa->addr)) { 120 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL); 121 found = 1; 122 addr->valid = 0; 123 list_del_rcu(&addr->list); 124 break; 125 } 126 } 127 spin_unlock_bh(&net->sctp.local_addr_lock); 128 if (found) 129 kfree_rcu(addr, rcu); 130 break; 131 } 132 133 return NOTIFY_DONE; 134 } 135 136 static struct notifier_block sctp_inet6addr_notifier = { 137 .notifier_call = sctp_inet6addr_event, 138 }; 139 140 /* ICMP error handler. */ 141 static void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 142 u8 type, u8 code, int offset, __be32 info) 143 { 144 struct inet6_dev *idev; 145 struct sock *sk; 146 struct sctp_association *asoc; 147 struct sctp_transport *transport; 148 struct ipv6_pinfo *np; 149 __u16 saveip, savesctp; 150 int err; 151 struct net *net = dev_net(skb->dev); 152 153 idev = in6_dev_get(skb->dev); 154 155 /* Fix up skb to look at the embedded net header. */ 156 saveip = skb->network_header; 157 savesctp = skb->transport_header; 158 skb_reset_network_header(skb); 159 skb_set_transport_header(skb, offset); 160 sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &transport); 161 /* Put back, the original pointers. */ 162 skb->network_header = saveip; 163 skb->transport_header = savesctp; 164 if (!sk) { 165 __ICMP6_INC_STATS(net, idev, ICMP6_MIB_INERRORS); 166 goto out; 167 } 168 169 /* Warning: The sock lock is held. Remember to call 170 * sctp_err_finish! 171 */ 172 173 switch (type) { 174 case ICMPV6_PKT_TOOBIG: 175 if (ip6_sk_accept_pmtu(sk)) 176 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info)); 177 goto out_unlock; 178 case ICMPV6_PARAMPROB: 179 if (ICMPV6_UNK_NEXTHDR == code) { 180 sctp_icmp_proto_unreachable(sk, asoc, transport); 181 goto out_unlock; 182 } 183 break; 184 case NDISC_REDIRECT: 185 sctp_icmp_redirect(sk, transport, skb); 186 goto out_unlock; 187 default: 188 break; 189 } 190 191 np = inet6_sk(sk); 192 icmpv6_err_convert(type, code, &err); 193 if (!sock_owned_by_user(sk) && np->recverr) { 194 sk->sk_err = err; 195 sk->sk_error_report(sk); 196 } else { /* Only an error on timeout */ 197 sk->sk_err_soft = err; 198 } 199 200 out_unlock: 201 sctp_err_finish(sk, transport); 202 out: 203 if (likely(idev != NULL)) 204 in6_dev_put(idev); 205 } 206 207 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport) 208 { 209 struct sock *sk = skb->sk; 210 struct ipv6_pinfo *np = inet6_sk(sk); 211 struct flowi6 *fl6 = &transport->fl.u.ip6; 212 int res; 213 214 pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb, 215 skb->len, &fl6->saddr, &fl6->daddr); 216 217 IP6_ECN_flow_xmit(sk, fl6->flowlabel); 218 219 if (!(transport->param_flags & SPP_PMTUD_ENABLE)) 220 skb->ignore_df = 1; 221 222 SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS); 223 224 rcu_read_lock(); 225 res = ip6_xmit(sk, skb, fl6, sk->sk_mark, rcu_dereference(np->opt), 226 np->tclass); 227 rcu_read_unlock(); 228 return res; 229 } 230 231 /* Returns the dst cache entry for the given source and destination ip 232 * addresses. 233 */ 234 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr, 235 struct flowi *fl, struct sock *sk) 236 { 237 struct sctp_association *asoc = t->asoc; 238 struct dst_entry *dst = NULL; 239 struct flowi6 *fl6 = &fl->u.ip6; 240 struct sctp_bind_addr *bp; 241 struct ipv6_pinfo *np = inet6_sk(sk); 242 struct sctp_sockaddr_entry *laddr; 243 union sctp_addr *baddr = NULL; 244 union sctp_addr *daddr = &t->ipaddr; 245 union sctp_addr dst_saddr; 246 struct in6_addr *final_p, final; 247 __u8 matchlen = 0; 248 __u8 bmatchlen; 249 sctp_scope_t scope; 250 251 memset(fl6, 0, sizeof(struct flowi6)); 252 fl6->daddr = daddr->v6.sin6_addr; 253 fl6->fl6_dport = daddr->v6.sin6_port; 254 fl6->flowi6_proto = IPPROTO_SCTP; 255 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 256 fl6->flowi6_oif = daddr->v6.sin6_scope_id; 257 258 pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr); 259 260 if (asoc) 261 fl6->fl6_sport = htons(asoc->base.bind_addr.port); 262 263 if (saddr) { 264 fl6->saddr = saddr->v6.sin6_addr; 265 fl6->fl6_sport = saddr->v6.sin6_port; 266 267 pr_debug("src=%pI6 - ", &fl6->saddr); 268 } 269 270 rcu_read_lock(); 271 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 272 rcu_read_unlock(); 273 274 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 275 if (!asoc || saddr) 276 goto out; 277 278 bp = &asoc->base.bind_addr; 279 scope = sctp_scope(daddr); 280 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check 281 * to see if we can use it. 282 */ 283 if (!IS_ERR(dst)) { 284 /* Walk through the bind address list and look for a bind 285 * address that matches the source address of the returned dst. 286 */ 287 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port)); 288 rcu_read_lock(); 289 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 290 if (!laddr->valid || laddr->state == SCTP_ADDR_DEL || 291 (laddr->state != SCTP_ADDR_SRC && 292 !asoc->src_out_of_asoc_ok)) 293 continue; 294 295 /* Do not compare against v4 addrs */ 296 if ((laddr->a.sa.sa_family == AF_INET6) && 297 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) { 298 rcu_read_unlock(); 299 goto out; 300 } 301 } 302 rcu_read_unlock(); 303 /* None of the bound addresses match the source address of the 304 * dst. So release it. 305 */ 306 dst_release(dst); 307 dst = NULL; 308 } 309 310 /* Walk through the bind address list and try to get the 311 * best source address for a given destination. 312 */ 313 rcu_read_lock(); 314 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 315 if (!laddr->valid) 316 continue; 317 if ((laddr->state == SCTP_ADDR_SRC) && 318 (laddr->a.sa.sa_family == AF_INET6) && 319 (scope <= sctp_scope(&laddr->a))) { 320 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a); 321 if (!baddr || (matchlen < bmatchlen)) { 322 baddr = &laddr->a; 323 matchlen = bmatchlen; 324 } 325 } 326 } 327 if (baddr) { 328 fl6->saddr = baddr->v6.sin6_addr; 329 fl6->fl6_sport = baddr->v6.sin6_port; 330 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 331 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 332 } 333 rcu_read_unlock(); 334 335 out: 336 if (!IS_ERR_OR_NULL(dst)) { 337 struct rt6_info *rt; 338 339 rt = (struct rt6_info *)dst; 340 t->dst = dst; 341 t->dst_cookie = rt6_get_cookie(rt); 342 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n", 343 &rt->rt6i_dst.addr, rt->rt6i_dst.plen, 344 &fl6->saddr); 345 } else { 346 t->dst = NULL; 347 348 pr_debug("no route\n"); 349 } 350 } 351 352 /* Returns the number of consecutive initial bits that match in the 2 ipv6 353 * addresses. 354 */ 355 static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 356 union sctp_addr *s2) 357 { 358 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr); 359 } 360 361 /* Fills in the source address(saddr) based on the destination address(daddr) 362 * and asoc's bind address list. 363 */ 364 static void sctp_v6_get_saddr(struct sctp_sock *sk, 365 struct sctp_transport *t, 366 struct flowi *fl) 367 { 368 struct flowi6 *fl6 = &fl->u.ip6; 369 union sctp_addr *saddr = &t->saddr; 370 371 pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst); 372 373 if (t->dst) { 374 saddr->v6.sin6_family = AF_INET6; 375 saddr->v6.sin6_addr = fl6->saddr; 376 } 377 } 378 379 /* Make a copy of all potential local addresses. */ 380 static void sctp_v6_copy_addrlist(struct list_head *addrlist, 381 struct net_device *dev) 382 { 383 struct inet6_dev *in6_dev; 384 struct inet6_ifaddr *ifp; 385 struct sctp_sockaddr_entry *addr; 386 387 rcu_read_lock(); 388 if ((in6_dev = __in6_dev_get(dev)) == NULL) { 389 rcu_read_unlock(); 390 return; 391 } 392 393 read_lock_bh(&in6_dev->lock); 394 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) { 395 /* Add the address to the local list. */ 396 addr = kzalloc(sizeof(*addr), GFP_ATOMIC); 397 if (addr) { 398 addr->a.v6.sin6_family = AF_INET6; 399 addr->a.v6.sin6_port = 0; 400 addr->a.v6.sin6_addr = ifp->addr; 401 addr->a.v6.sin6_scope_id = dev->ifindex; 402 addr->valid = 1; 403 INIT_LIST_HEAD(&addr->list); 404 list_add_tail(&addr->list, addrlist); 405 } 406 } 407 408 read_unlock_bh(&in6_dev->lock); 409 rcu_read_unlock(); 410 } 411 412 /* Initialize a sockaddr_storage from in incoming skb. */ 413 static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb, 414 int is_saddr) 415 { 416 __be16 *port; 417 struct sctphdr *sh; 418 419 port = &addr->v6.sin6_port; 420 addr->v6.sin6_family = AF_INET6; 421 addr->v6.sin6_flowinfo = 0; /* FIXME */ 422 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif; 423 424 /* Always called on head skb, so this is safe */ 425 sh = sctp_hdr(skb); 426 if (is_saddr) { 427 *port = sh->source; 428 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 429 } else { 430 *port = sh->dest; 431 addr->v6.sin6_addr = ipv6_hdr(skb)->daddr; 432 } 433 } 434 435 /* Initialize an sctp_addr from a socket. */ 436 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk) 437 { 438 addr->v6.sin6_family = AF_INET6; 439 addr->v6.sin6_port = 0; 440 addr->v6.sin6_addr = sk->sk_v6_rcv_saddr; 441 } 442 443 /* Initialize sk->sk_rcv_saddr from sctp_addr. */ 444 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk) 445 { 446 if (addr->sa.sa_family == AF_INET) { 447 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0; 448 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0; 449 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff); 450 sk->sk_v6_rcv_saddr.s6_addr32[3] = 451 addr->v4.sin_addr.s_addr; 452 } else { 453 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr; 454 } 455 } 456 457 /* Initialize sk->sk_daddr from sctp_addr. */ 458 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk) 459 { 460 if (addr->sa.sa_family == AF_INET) { 461 sk->sk_v6_daddr.s6_addr32[0] = 0; 462 sk->sk_v6_daddr.s6_addr32[1] = 0; 463 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff); 464 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr; 465 } else { 466 sk->sk_v6_daddr = addr->v6.sin6_addr; 467 } 468 } 469 470 /* Initialize a sctp_addr from an address parameter. */ 471 static void sctp_v6_from_addr_param(union sctp_addr *addr, 472 union sctp_addr_param *param, 473 __be16 port, int iif) 474 { 475 addr->v6.sin6_family = AF_INET6; 476 addr->v6.sin6_port = port; 477 addr->v6.sin6_flowinfo = 0; /* BUG */ 478 addr->v6.sin6_addr = param->v6.addr; 479 addr->v6.sin6_scope_id = iif; 480 } 481 482 /* Initialize an address parameter from a sctp_addr and return the length 483 * of the address parameter. 484 */ 485 static int sctp_v6_to_addr_param(const union sctp_addr *addr, 486 union sctp_addr_param *param) 487 { 488 int length = sizeof(sctp_ipv6addr_param_t); 489 490 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS; 491 param->v6.param_hdr.length = htons(length); 492 param->v6.addr = addr->v6.sin6_addr; 493 494 return length; 495 } 496 497 /* Initialize a sctp_addr from struct in6_addr. */ 498 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 499 __be16 port) 500 { 501 addr->sa.sa_family = AF_INET6; 502 addr->v6.sin6_port = port; 503 addr->v6.sin6_addr = *saddr; 504 } 505 506 /* Compare addresses exactly. 507 * v4-mapped-v6 is also in consideration. 508 */ 509 static int sctp_v6_cmp_addr(const union sctp_addr *addr1, 510 const union sctp_addr *addr2) 511 { 512 if (addr1->sa.sa_family != addr2->sa.sa_family) { 513 if (addr1->sa.sa_family == AF_INET && 514 addr2->sa.sa_family == AF_INET6 && 515 ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) { 516 if (addr2->v6.sin6_port == addr1->v4.sin_port && 517 addr2->v6.sin6_addr.s6_addr32[3] == 518 addr1->v4.sin_addr.s_addr) 519 return 1; 520 } 521 if (addr2->sa.sa_family == AF_INET && 522 addr1->sa.sa_family == AF_INET6 && 523 ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) { 524 if (addr1->v6.sin6_port == addr2->v4.sin_port && 525 addr1->v6.sin6_addr.s6_addr32[3] == 526 addr2->v4.sin_addr.s_addr) 527 return 1; 528 } 529 return 0; 530 } 531 if (addr1->v6.sin6_port != addr2->v6.sin6_port) 532 return 0; 533 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr)) 534 return 0; 535 /* If this is a linklocal address, compare the scope_id. */ 536 if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) { 537 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id && 538 (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) { 539 return 0; 540 } 541 } 542 543 return 1; 544 } 545 546 /* Initialize addr struct to INADDR_ANY. */ 547 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port) 548 { 549 memset(addr, 0x00, sizeof(union sctp_addr)); 550 addr->v6.sin6_family = AF_INET6; 551 addr->v6.sin6_port = port; 552 } 553 554 /* Is this a wildcard address? */ 555 static int sctp_v6_is_any(const union sctp_addr *addr) 556 { 557 return ipv6_addr_any(&addr->v6.sin6_addr); 558 } 559 560 /* Should this be available for binding? */ 561 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp) 562 { 563 int type; 564 struct net *net = sock_net(&sp->inet.sk); 565 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr; 566 567 type = ipv6_addr_type(in6); 568 if (IPV6_ADDR_ANY == type) 569 return 1; 570 if (type == IPV6_ADDR_MAPPED) { 571 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 572 return 0; 573 sctp_v6_map_v4(addr); 574 return sctp_get_af_specific(AF_INET)->available(addr, sp); 575 } 576 if (!(type & IPV6_ADDR_UNICAST)) 577 return 0; 578 579 return sp->inet.freebind || net->ipv6.sysctl.ip_nonlocal_bind || 580 ipv6_chk_addr(net, in6, NULL, 0); 581 } 582 583 /* This function checks if the address is a valid address to be used for 584 * SCTP. 585 * 586 * Output: 587 * Return 0 - If the address is a non-unicast or an illegal address. 588 * Return 1 - If the address is a unicast. 589 */ 590 static int sctp_v6_addr_valid(union sctp_addr *addr, 591 struct sctp_sock *sp, 592 const struct sk_buff *skb) 593 { 594 int ret = ipv6_addr_type(&addr->v6.sin6_addr); 595 596 /* Support v4-mapped-v6 address. */ 597 if (ret == IPV6_ADDR_MAPPED) { 598 /* Note: This routine is used in input, so v4-mapped-v6 599 * are disallowed here when there is no sctp_sock. 600 */ 601 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 602 return 0; 603 sctp_v6_map_v4(addr); 604 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb); 605 } 606 607 /* Is this a non-unicast address */ 608 if (!(ret & IPV6_ADDR_UNICAST)) 609 return 0; 610 611 return 1; 612 } 613 614 /* What is the scope of 'addr'? */ 615 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr) 616 { 617 int v6scope; 618 sctp_scope_t retval; 619 620 /* The IPv6 scope is really a set of bit fields. 621 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope. 622 */ 623 624 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr); 625 switch (v6scope) { 626 case IFA_HOST: 627 retval = SCTP_SCOPE_LOOPBACK; 628 break; 629 case IFA_LINK: 630 retval = SCTP_SCOPE_LINK; 631 break; 632 case IFA_SITE: 633 retval = SCTP_SCOPE_PRIVATE; 634 break; 635 default: 636 retval = SCTP_SCOPE_GLOBAL; 637 break; 638 } 639 640 return retval; 641 } 642 643 /* Create and initialize a new sk for the socket to be returned by accept(). */ 644 static struct sock *sctp_v6_create_accept_sk(struct sock *sk, 645 struct sctp_association *asoc) 646 { 647 struct sock *newsk; 648 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 649 struct sctp6_sock *newsctp6sk; 650 struct ipv6_txoptions *opt; 651 652 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, 0); 653 if (!newsk) 654 goto out; 655 656 sock_init_data(NULL, newsk); 657 658 sctp_copy_sock(newsk, sk, asoc); 659 sock_reset_flag(sk, SOCK_ZAPPED); 660 661 newsctp6sk = (struct sctp6_sock *)newsk; 662 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6; 663 664 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped; 665 666 newnp = inet6_sk(newsk); 667 668 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 669 670 rcu_read_lock(); 671 opt = rcu_dereference(np->opt); 672 if (opt) 673 opt = ipv6_dup_options(newsk, opt); 674 RCU_INIT_POINTER(newnp->opt, opt); 675 rcu_read_unlock(); 676 677 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() 678 * and getpeername(). 679 */ 680 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk); 681 682 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr; 683 684 sk_refcnt_debug_inc(newsk); 685 686 if (newsk->sk_prot->init(newsk)) { 687 sk_common_release(newsk); 688 newsk = NULL; 689 } 690 691 out: 692 return newsk; 693 } 694 695 /* Format a sockaddr for return to user space. This makes sure the return is 696 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. 697 */ 698 static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr) 699 { 700 if (sp->v4mapped) { 701 if (addr->sa.sa_family == AF_INET) 702 sctp_v4_map_v6(addr); 703 } else { 704 if (addr->sa.sa_family == AF_INET6 && 705 ipv6_addr_v4mapped(&addr->v6.sin6_addr)) 706 sctp_v6_map_v4(addr); 707 } 708 709 if (addr->sa.sa_family == AF_INET) 710 return sizeof(struct sockaddr_in); 711 return sizeof(struct sockaddr_in6); 712 } 713 714 /* Where did this skb come from? */ 715 static int sctp_v6_skb_iif(const struct sk_buff *skb) 716 { 717 return IP6CB(skb)->iif; 718 } 719 720 /* Was this packet marked by Explicit Congestion Notification? */ 721 static int sctp_v6_is_ce(const struct sk_buff *skb) 722 { 723 return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20); 724 } 725 726 /* Dump the v6 addr to the seq file. */ 727 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr) 728 { 729 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr); 730 } 731 732 static void sctp_v6_ecn_capable(struct sock *sk) 733 { 734 inet6_sk(sk)->tclass |= INET_ECN_ECT_0; 735 } 736 737 /* Initialize a PF_INET msgname from a ulpevent. */ 738 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event, 739 char *msgname, int *addrlen) 740 { 741 union sctp_addr *addr; 742 struct sctp_association *asoc; 743 union sctp_addr *paddr; 744 745 if (!msgname) 746 return; 747 748 addr = (union sctp_addr *)msgname; 749 asoc = event->asoc; 750 paddr = &asoc->peer.primary_addr; 751 752 if (paddr->sa.sa_family == AF_INET) { 753 addr->v4.sin_family = AF_INET; 754 addr->v4.sin_port = htons(asoc->peer.port); 755 addr->v4.sin_addr = paddr->v4.sin_addr; 756 } else { 757 addr->v6.sin6_family = AF_INET6; 758 addr->v6.sin6_flowinfo = 0; 759 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 760 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id; 761 else 762 addr->v6.sin6_scope_id = 0; 763 addr->v6.sin6_port = htons(asoc->peer.port); 764 addr->v6.sin6_addr = paddr->v6.sin6_addr; 765 } 766 767 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr); 768 } 769 770 /* Initialize a msg_name from an inbound skb. */ 771 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname, 772 int *addr_len) 773 { 774 union sctp_addr *addr; 775 struct sctphdr *sh; 776 777 if (!msgname) 778 return; 779 780 addr = (union sctp_addr *)msgname; 781 sh = sctp_hdr(skb); 782 783 if (ip_hdr(skb)->version == 4) { 784 addr->v4.sin_family = AF_INET; 785 addr->v4.sin_port = sh->source; 786 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr; 787 } else { 788 addr->v6.sin6_family = AF_INET6; 789 addr->v6.sin6_flowinfo = 0; 790 addr->v6.sin6_port = sh->source; 791 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 792 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) { 793 addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb); 794 } 795 } 796 797 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr); 798 } 799 800 /* Do we support this AF? */ 801 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp) 802 { 803 switch (family) { 804 case AF_INET6: 805 return 1; 806 /* v4-mapped-v6 addresses */ 807 case AF_INET: 808 if (!__ipv6_only_sock(sctp_opt2sk(sp))) 809 return 1; 810 default: 811 return 0; 812 } 813 } 814 815 /* Address matching with wildcards allowed. This extra level 816 * of indirection lets us choose whether a PF_INET6 should 817 * disallow any v4 addresses if we so choose. 818 */ 819 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, 820 const union sctp_addr *addr2, 821 struct sctp_sock *opt) 822 { 823 struct sctp_af *af1, *af2; 824 struct sock *sk = sctp_opt2sk(opt); 825 826 af1 = sctp_get_af_specific(addr1->sa.sa_family); 827 af2 = sctp_get_af_specific(addr2->sa.sa_family); 828 829 if (!af1 || !af2) 830 return 0; 831 832 /* If the socket is IPv6 only, v4 addrs will not match */ 833 if (__ipv6_only_sock(sk) && af1 != af2) 834 return 0; 835 836 /* Today, wildcard AF_INET/AF_INET6. */ 837 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2)) 838 return 1; 839 840 if (addr1->sa.sa_family != addr2->sa.sa_family) 841 return 0; 842 843 return af1->cmp_addr(addr1, addr2); 844 } 845 846 /* Verify that the provided sockaddr looks bindable. Common verification, 847 * has already been taken care of. 848 */ 849 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr) 850 { 851 struct sctp_af *af; 852 853 /* ASSERT: address family has already been verified. */ 854 if (addr->sa.sa_family != AF_INET6) 855 af = sctp_get_af_specific(addr->sa.sa_family); 856 else { 857 int type = ipv6_addr_type(&addr->v6.sin6_addr); 858 struct net_device *dev; 859 860 if (type & IPV6_ADDR_LINKLOCAL) { 861 struct net *net; 862 if (!addr->v6.sin6_scope_id) 863 return 0; 864 net = sock_net(&opt->inet.sk); 865 rcu_read_lock(); 866 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id); 867 if (!dev || 868 !ipv6_chk_addr(net, &addr->v6.sin6_addr, dev, 0)) { 869 rcu_read_unlock(); 870 return 0; 871 } 872 rcu_read_unlock(); 873 } 874 875 af = opt->pf->af; 876 } 877 return af->available(addr, opt); 878 } 879 880 /* Verify that the provided sockaddr looks sendable. Common verification, 881 * has already been taken care of. 882 */ 883 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr) 884 { 885 struct sctp_af *af = NULL; 886 887 /* ASSERT: address family has already been verified. */ 888 if (addr->sa.sa_family != AF_INET6) 889 af = sctp_get_af_specific(addr->sa.sa_family); 890 else { 891 int type = ipv6_addr_type(&addr->v6.sin6_addr); 892 struct net_device *dev; 893 894 if (type & IPV6_ADDR_LINKLOCAL) { 895 if (!addr->v6.sin6_scope_id) 896 return 0; 897 rcu_read_lock(); 898 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk), 899 addr->v6.sin6_scope_id); 900 rcu_read_unlock(); 901 if (!dev) 902 return 0; 903 } 904 af = opt->pf->af; 905 } 906 907 return af != NULL; 908 } 909 910 /* Fill in Supported Address Type information for INIT and INIT-ACK 911 * chunks. Note: In the future, we may want to look at sock options 912 * to determine whether a PF_INET6 socket really wants to have IPV4 913 * addresses. 914 * Returns number of addresses supported. 915 */ 916 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt, 917 __be16 *types) 918 { 919 types[0] = SCTP_PARAM_IPV6_ADDRESS; 920 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) { 921 types[1] = SCTP_PARAM_IPV4_ADDRESS; 922 return 2; 923 } 924 return 1; 925 } 926 927 /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */ 928 static int sctp_getname(struct socket *sock, struct sockaddr *uaddr, 929 int *uaddr_len, int peer) 930 { 931 int rc; 932 933 rc = inet6_getname(sock, uaddr, uaddr_len, peer); 934 935 if (rc != 0) 936 return rc; 937 938 *uaddr_len = sctp_v6_addr_to_user(sctp_sk(sock->sk), 939 (union sctp_addr *)uaddr); 940 941 return rc; 942 } 943 944 static const struct proto_ops inet6_seqpacket_ops = { 945 .family = PF_INET6, 946 .owner = THIS_MODULE, 947 .release = inet6_release, 948 .bind = inet6_bind, 949 .connect = inet_dgram_connect, 950 .socketpair = sock_no_socketpair, 951 .accept = inet_accept, 952 .getname = sctp_getname, 953 .poll = sctp_poll, 954 .ioctl = inet6_ioctl, 955 .listen = sctp_inet_listen, 956 .shutdown = inet_shutdown, 957 .setsockopt = sock_common_setsockopt, 958 .getsockopt = sock_common_getsockopt, 959 .sendmsg = inet_sendmsg, 960 .recvmsg = inet_recvmsg, 961 .mmap = sock_no_mmap, 962 #ifdef CONFIG_COMPAT 963 .compat_setsockopt = compat_sock_common_setsockopt, 964 .compat_getsockopt = compat_sock_common_getsockopt, 965 #endif 966 }; 967 968 static struct inet_protosw sctpv6_seqpacket_protosw = { 969 .type = SOCK_SEQPACKET, 970 .protocol = IPPROTO_SCTP, 971 .prot = &sctpv6_prot, 972 .ops = &inet6_seqpacket_ops, 973 .flags = SCTP_PROTOSW_FLAG 974 }; 975 static struct inet_protosw sctpv6_stream_protosw = { 976 .type = SOCK_STREAM, 977 .protocol = IPPROTO_SCTP, 978 .prot = &sctpv6_prot, 979 .ops = &inet6_seqpacket_ops, 980 .flags = SCTP_PROTOSW_FLAG, 981 }; 982 983 static int sctp6_rcv(struct sk_buff *skb) 984 { 985 return sctp_rcv(skb) ? -1 : 0; 986 } 987 988 static const struct inet6_protocol sctpv6_protocol = { 989 .handler = sctp6_rcv, 990 .err_handler = sctp_v6_err, 991 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, 992 }; 993 994 static struct sctp_af sctp_af_inet6 = { 995 .sa_family = AF_INET6, 996 .sctp_xmit = sctp_v6_xmit, 997 .setsockopt = ipv6_setsockopt, 998 .getsockopt = ipv6_getsockopt, 999 .get_dst = sctp_v6_get_dst, 1000 .get_saddr = sctp_v6_get_saddr, 1001 .copy_addrlist = sctp_v6_copy_addrlist, 1002 .from_skb = sctp_v6_from_skb, 1003 .from_sk = sctp_v6_from_sk, 1004 .from_addr_param = sctp_v6_from_addr_param, 1005 .to_addr_param = sctp_v6_to_addr_param, 1006 .cmp_addr = sctp_v6_cmp_addr, 1007 .scope = sctp_v6_scope, 1008 .addr_valid = sctp_v6_addr_valid, 1009 .inaddr_any = sctp_v6_inaddr_any, 1010 .is_any = sctp_v6_is_any, 1011 .available = sctp_v6_available, 1012 .skb_iif = sctp_v6_skb_iif, 1013 .is_ce = sctp_v6_is_ce, 1014 .seq_dump_addr = sctp_v6_seq_dump_addr, 1015 .ecn_capable = sctp_v6_ecn_capable, 1016 .net_header_len = sizeof(struct ipv6hdr), 1017 .sockaddr_len = sizeof(struct sockaddr_in6), 1018 #ifdef CONFIG_COMPAT 1019 .compat_setsockopt = compat_ipv6_setsockopt, 1020 .compat_getsockopt = compat_ipv6_getsockopt, 1021 #endif 1022 }; 1023 1024 static struct sctp_pf sctp_pf_inet6 = { 1025 .event_msgname = sctp_inet6_event_msgname, 1026 .skb_msgname = sctp_inet6_skb_msgname, 1027 .af_supported = sctp_inet6_af_supported, 1028 .cmp_addr = sctp_inet6_cmp_addr, 1029 .bind_verify = sctp_inet6_bind_verify, 1030 .send_verify = sctp_inet6_send_verify, 1031 .supported_addrs = sctp_inet6_supported_addrs, 1032 .create_accept_sk = sctp_v6_create_accept_sk, 1033 .addr_to_user = sctp_v6_addr_to_user, 1034 .to_sk_saddr = sctp_v6_to_sk_saddr, 1035 .to_sk_daddr = sctp_v6_to_sk_daddr, 1036 .af = &sctp_af_inet6, 1037 }; 1038 1039 /* Initialize IPv6 support and register with socket layer. */ 1040 void sctp_v6_pf_init(void) 1041 { 1042 /* Register the SCTP specific PF_INET6 functions. */ 1043 sctp_register_pf(&sctp_pf_inet6, PF_INET6); 1044 1045 /* Register the SCTP specific AF_INET6 functions. */ 1046 sctp_register_af(&sctp_af_inet6); 1047 } 1048 1049 void sctp_v6_pf_exit(void) 1050 { 1051 list_del(&sctp_af_inet6.list); 1052 } 1053 1054 /* Initialize IPv6 support and register with socket layer. */ 1055 int sctp_v6_protosw_init(void) 1056 { 1057 int rc; 1058 1059 rc = proto_register(&sctpv6_prot, 1); 1060 if (rc) 1061 return rc; 1062 1063 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */ 1064 inet6_register_protosw(&sctpv6_seqpacket_protosw); 1065 inet6_register_protosw(&sctpv6_stream_protosw); 1066 1067 return 0; 1068 } 1069 1070 void sctp_v6_protosw_exit(void) 1071 { 1072 inet6_unregister_protosw(&sctpv6_seqpacket_protosw); 1073 inet6_unregister_protosw(&sctpv6_stream_protosw); 1074 proto_unregister(&sctpv6_prot); 1075 } 1076 1077 1078 /* Register with inet6 layer. */ 1079 int sctp_v6_add_protocol(void) 1080 { 1081 /* Register notifier for inet6 address additions/deletions. */ 1082 register_inet6addr_notifier(&sctp_inet6addr_notifier); 1083 1084 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0) 1085 return -EAGAIN; 1086 1087 return 0; 1088 } 1089 1090 /* Unregister with inet6 layer. */ 1091 void sctp_v6_del_protocol(void) 1092 { 1093 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP); 1094 unregister_inet6addr_notifier(&sctp_inet6addr_notifier); 1095 } 1096