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 <asm/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, asoc); 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, rcu_dereference(np->opt), np->tclass); 226 rcu_read_unlock(); 227 return res; 228 } 229 230 /* Returns the dst cache entry for the given source and destination ip 231 * addresses. 232 */ 233 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr, 234 struct flowi *fl, struct sock *sk) 235 { 236 struct sctp_association *asoc = t->asoc; 237 struct dst_entry *dst = NULL; 238 struct flowi6 *fl6 = &fl->u.ip6; 239 struct sctp_bind_addr *bp; 240 struct ipv6_pinfo *np = inet6_sk(sk); 241 struct sctp_sockaddr_entry *laddr; 242 union sctp_addr *baddr = NULL; 243 union sctp_addr *daddr = &t->ipaddr; 244 union sctp_addr dst_saddr; 245 struct in6_addr *final_p, final; 246 __u8 matchlen = 0; 247 __u8 bmatchlen; 248 sctp_scope_t scope; 249 250 memset(fl6, 0, sizeof(struct flowi6)); 251 fl6->daddr = daddr->v6.sin6_addr; 252 fl6->fl6_dport = daddr->v6.sin6_port; 253 fl6->flowi6_proto = IPPROTO_SCTP; 254 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 255 fl6->flowi6_oif = daddr->v6.sin6_scope_id; 256 257 pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr); 258 259 if (asoc) 260 fl6->fl6_sport = htons(asoc->base.bind_addr.port); 261 262 if (saddr) { 263 fl6->saddr = saddr->v6.sin6_addr; 264 fl6->fl6_sport = saddr->v6.sin6_port; 265 266 pr_debug("src=%pI6 - ", &fl6->saddr); 267 } 268 269 rcu_read_lock(); 270 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 271 rcu_read_unlock(); 272 273 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 274 if (!asoc || saddr) 275 goto out; 276 277 bp = &asoc->base.bind_addr; 278 scope = sctp_scope(daddr); 279 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check 280 * to see if we can use it. 281 */ 282 if (!IS_ERR(dst)) { 283 /* Walk through the bind address list and look for a bind 284 * address that matches the source address of the returned dst. 285 */ 286 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port)); 287 rcu_read_lock(); 288 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 289 if (!laddr->valid || laddr->state == SCTP_ADDR_DEL || 290 (laddr->state != SCTP_ADDR_SRC && 291 !asoc->src_out_of_asoc_ok)) 292 continue; 293 294 /* Do not compare against v4 addrs */ 295 if ((laddr->a.sa.sa_family == AF_INET6) && 296 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) { 297 rcu_read_unlock(); 298 goto out; 299 } 300 } 301 rcu_read_unlock(); 302 /* None of the bound addresses match the source address of the 303 * dst. So release it. 304 */ 305 dst_release(dst); 306 dst = NULL; 307 } 308 309 /* Walk through the bind address list and try to get the 310 * best source address for a given destination. 311 */ 312 rcu_read_lock(); 313 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 314 if (!laddr->valid) 315 continue; 316 if ((laddr->state == SCTP_ADDR_SRC) && 317 (laddr->a.sa.sa_family == AF_INET6) && 318 (scope <= sctp_scope(&laddr->a))) { 319 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a); 320 if (!baddr || (matchlen < bmatchlen)) { 321 baddr = &laddr->a; 322 matchlen = bmatchlen; 323 } 324 } 325 } 326 if (baddr) { 327 fl6->saddr = baddr->v6.sin6_addr; 328 fl6->fl6_sport = baddr->v6.sin6_port; 329 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 330 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 331 } 332 rcu_read_unlock(); 333 334 out: 335 if (!IS_ERR_OR_NULL(dst)) { 336 struct rt6_info *rt; 337 338 rt = (struct rt6_info *)dst; 339 t->dst = dst; 340 t->dst_cookie = rt6_get_cookie(rt); 341 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n", 342 &rt->rt6i_dst.addr, rt->rt6i_dst.plen, 343 &fl6->saddr); 344 } else { 345 t->dst = NULL; 346 347 pr_debug("no route\n"); 348 } 349 } 350 351 /* Returns the number of consecutive initial bits that match in the 2 ipv6 352 * addresses. 353 */ 354 static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 355 union sctp_addr *s2) 356 { 357 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr); 358 } 359 360 /* Fills in the source address(saddr) based on the destination address(daddr) 361 * and asoc's bind address list. 362 */ 363 static void sctp_v6_get_saddr(struct sctp_sock *sk, 364 struct sctp_transport *t, 365 struct flowi *fl) 366 { 367 struct flowi6 *fl6 = &fl->u.ip6; 368 union sctp_addr *saddr = &t->saddr; 369 370 pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst); 371 372 if (t->dst) { 373 saddr->v6.sin6_family = AF_INET6; 374 saddr->v6.sin6_addr = fl6->saddr; 375 } 376 } 377 378 /* Make a copy of all potential local addresses. */ 379 static void sctp_v6_copy_addrlist(struct list_head *addrlist, 380 struct net_device *dev) 381 { 382 struct inet6_dev *in6_dev; 383 struct inet6_ifaddr *ifp; 384 struct sctp_sockaddr_entry *addr; 385 386 rcu_read_lock(); 387 if ((in6_dev = __in6_dev_get(dev)) == NULL) { 388 rcu_read_unlock(); 389 return; 390 } 391 392 read_lock_bh(&in6_dev->lock); 393 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) { 394 /* Add the address to the local list. */ 395 addr = kzalloc(sizeof(*addr), GFP_ATOMIC); 396 if (addr) { 397 addr->a.v6.sin6_family = AF_INET6; 398 addr->a.v6.sin6_port = 0; 399 addr->a.v6.sin6_addr = ifp->addr; 400 addr->a.v6.sin6_scope_id = dev->ifindex; 401 addr->valid = 1; 402 INIT_LIST_HEAD(&addr->list); 403 list_add_tail(&addr->list, addrlist); 404 } 405 } 406 407 read_unlock_bh(&in6_dev->lock); 408 rcu_read_unlock(); 409 } 410 411 /* Initialize a sockaddr_storage from in incoming skb. */ 412 static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb, 413 int is_saddr) 414 { 415 __be16 *port; 416 struct sctphdr *sh; 417 418 port = &addr->v6.sin6_port; 419 addr->v6.sin6_family = AF_INET6; 420 addr->v6.sin6_flowinfo = 0; /* FIXME */ 421 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif; 422 423 /* Always called on head skb, so this is safe */ 424 sh = sctp_hdr(skb); 425 if (is_saddr) { 426 *port = sh->source; 427 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 428 } else { 429 *port = sh->dest; 430 addr->v6.sin6_addr = ipv6_hdr(skb)->daddr; 431 } 432 } 433 434 /* Initialize an sctp_addr from a socket. */ 435 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk) 436 { 437 addr->v6.sin6_family = AF_INET6; 438 addr->v6.sin6_port = 0; 439 addr->v6.sin6_addr = sk->sk_v6_rcv_saddr; 440 } 441 442 /* Initialize sk->sk_rcv_saddr from sctp_addr. */ 443 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk) 444 { 445 if (addr->sa.sa_family == AF_INET) { 446 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0; 447 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0; 448 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff); 449 sk->sk_v6_rcv_saddr.s6_addr32[3] = 450 addr->v4.sin_addr.s_addr; 451 } else { 452 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr; 453 } 454 } 455 456 /* Initialize sk->sk_daddr from sctp_addr. */ 457 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk) 458 { 459 if (addr->sa.sa_family == AF_INET) { 460 sk->sk_v6_daddr.s6_addr32[0] = 0; 461 sk->sk_v6_daddr.s6_addr32[1] = 0; 462 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff); 463 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr; 464 } else { 465 sk->sk_v6_daddr = addr->v6.sin6_addr; 466 } 467 } 468 469 /* Initialize a sctp_addr from an address parameter. */ 470 static void sctp_v6_from_addr_param(union sctp_addr *addr, 471 union sctp_addr_param *param, 472 __be16 port, int iif) 473 { 474 addr->v6.sin6_family = AF_INET6; 475 addr->v6.sin6_port = port; 476 addr->v6.sin6_flowinfo = 0; /* BUG */ 477 addr->v6.sin6_addr = param->v6.addr; 478 addr->v6.sin6_scope_id = iif; 479 } 480 481 /* Initialize an address parameter from a sctp_addr and return the length 482 * of the address parameter. 483 */ 484 static int sctp_v6_to_addr_param(const union sctp_addr *addr, 485 union sctp_addr_param *param) 486 { 487 int length = sizeof(sctp_ipv6addr_param_t); 488 489 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS; 490 param->v6.param_hdr.length = htons(length); 491 param->v6.addr = addr->v6.sin6_addr; 492 493 return length; 494 } 495 496 /* Initialize a sctp_addr from struct in6_addr. */ 497 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 498 __be16 port) 499 { 500 addr->sa.sa_family = AF_INET6; 501 addr->v6.sin6_port = port; 502 addr->v6.sin6_addr = *saddr; 503 } 504 505 /* Compare addresses exactly. 506 * v4-mapped-v6 is also in consideration. 507 */ 508 static int sctp_v6_cmp_addr(const union sctp_addr *addr1, 509 const union sctp_addr *addr2) 510 { 511 if (addr1->sa.sa_family != addr2->sa.sa_family) { 512 if (addr1->sa.sa_family == AF_INET && 513 addr2->sa.sa_family == AF_INET6 && 514 ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) { 515 if (addr2->v6.sin6_port == addr1->v4.sin_port && 516 addr2->v6.sin6_addr.s6_addr32[3] == 517 addr1->v4.sin_addr.s_addr) 518 return 1; 519 } 520 if (addr2->sa.sa_family == AF_INET && 521 addr1->sa.sa_family == AF_INET6 && 522 ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) { 523 if (addr1->v6.sin6_port == addr2->v4.sin_port && 524 addr1->v6.sin6_addr.s6_addr32[3] == 525 addr2->v4.sin_addr.s_addr) 526 return 1; 527 } 528 return 0; 529 } 530 if (addr1->v6.sin6_port != addr2->v6.sin6_port) 531 return 0; 532 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr)) 533 return 0; 534 /* If this is a linklocal address, compare the scope_id. */ 535 if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) { 536 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id && 537 (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) { 538 return 0; 539 } 540 } 541 542 return 1; 543 } 544 545 /* Initialize addr struct to INADDR_ANY. */ 546 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port) 547 { 548 memset(addr, 0x00, sizeof(union sctp_addr)); 549 addr->v6.sin6_family = AF_INET6; 550 addr->v6.sin6_port = port; 551 } 552 553 /* Is this a wildcard address? */ 554 static int sctp_v6_is_any(const union sctp_addr *addr) 555 { 556 return ipv6_addr_any(&addr->v6.sin6_addr); 557 } 558 559 /* Should this be available for binding? */ 560 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp) 561 { 562 int type; 563 struct net *net = sock_net(&sp->inet.sk); 564 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr; 565 566 type = ipv6_addr_type(in6); 567 if (IPV6_ADDR_ANY == type) 568 return 1; 569 if (type == IPV6_ADDR_MAPPED) { 570 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 571 return 0; 572 sctp_v6_map_v4(addr); 573 return sctp_get_af_specific(AF_INET)->available(addr, sp); 574 } 575 if (!(type & IPV6_ADDR_UNICAST)) 576 return 0; 577 578 return sp->inet.freebind || net->ipv6.sysctl.ip_nonlocal_bind || 579 ipv6_chk_addr(net, in6, NULL, 0); 580 } 581 582 /* This function checks if the address is a valid address to be used for 583 * SCTP. 584 * 585 * Output: 586 * Return 0 - If the address is a non-unicast or an illegal address. 587 * Return 1 - If the address is a unicast. 588 */ 589 static int sctp_v6_addr_valid(union sctp_addr *addr, 590 struct sctp_sock *sp, 591 const struct sk_buff *skb) 592 { 593 int ret = ipv6_addr_type(&addr->v6.sin6_addr); 594 595 /* Support v4-mapped-v6 address. */ 596 if (ret == IPV6_ADDR_MAPPED) { 597 /* Note: This routine is used in input, so v4-mapped-v6 598 * are disallowed here when there is no sctp_sock. 599 */ 600 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 601 return 0; 602 sctp_v6_map_v4(addr); 603 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb); 604 } 605 606 /* Is this a non-unicast address */ 607 if (!(ret & IPV6_ADDR_UNICAST)) 608 return 0; 609 610 return 1; 611 } 612 613 /* What is the scope of 'addr'? */ 614 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr) 615 { 616 int v6scope; 617 sctp_scope_t retval; 618 619 /* The IPv6 scope is really a set of bit fields. 620 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope. 621 */ 622 623 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr); 624 switch (v6scope) { 625 case IFA_HOST: 626 retval = SCTP_SCOPE_LOOPBACK; 627 break; 628 case IFA_LINK: 629 retval = SCTP_SCOPE_LINK; 630 break; 631 case IFA_SITE: 632 retval = SCTP_SCOPE_PRIVATE; 633 break; 634 default: 635 retval = SCTP_SCOPE_GLOBAL; 636 break; 637 } 638 639 return retval; 640 } 641 642 /* Create and initialize a new sk for the socket to be returned by accept(). */ 643 static struct sock *sctp_v6_create_accept_sk(struct sock *sk, 644 struct sctp_association *asoc) 645 { 646 struct sock *newsk; 647 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 648 struct sctp6_sock *newsctp6sk; 649 struct ipv6_txoptions *opt; 650 651 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, 0); 652 if (!newsk) 653 goto out; 654 655 sock_init_data(NULL, newsk); 656 657 sctp_copy_sock(newsk, sk, asoc); 658 sock_reset_flag(sk, SOCK_ZAPPED); 659 660 newsctp6sk = (struct sctp6_sock *)newsk; 661 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6; 662 663 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped; 664 665 newnp = inet6_sk(newsk); 666 667 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 668 669 rcu_read_lock(); 670 opt = rcu_dereference(np->opt); 671 if (opt) 672 opt = ipv6_dup_options(newsk, opt); 673 RCU_INIT_POINTER(newnp->opt, opt); 674 rcu_read_unlock(); 675 676 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() 677 * and getpeername(). 678 */ 679 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk); 680 681 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr; 682 683 sk_refcnt_debug_inc(newsk); 684 685 if (newsk->sk_prot->init(newsk)) { 686 sk_common_release(newsk); 687 newsk = NULL; 688 } 689 690 out: 691 return newsk; 692 } 693 694 /* Format a sockaddr for return to user space. This makes sure the return is 695 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. 696 */ 697 static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr) 698 { 699 if (sp->v4mapped) { 700 if (addr->sa.sa_family == AF_INET) 701 sctp_v4_map_v6(addr); 702 } else { 703 if (addr->sa.sa_family == AF_INET6 && 704 ipv6_addr_v4mapped(&addr->v6.sin6_addr)) 705 sctp_v6_map_v4(addr); 706 } 707 708 if (addr->sa.sa_family == AF_INET) 709 return sizeof(struct sockaddr_in); 710 return sizeof(struct sockaddr_in6); 711 } 712 713 /* Where did this skb come from? */ 714 static int sctp_v6_skb_iif(const struct sk_buff *skb) 715 { 716 return IP6CB(skb)->iif; 717 } 718 719 /* Was this packet marked by Explicit Congestion Notification? */ 720 static int sctp_v6_is_ce(const struct sk_buff *skb) 721 { 722 return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20); 723 } 724 725 /* Dump the v6 addr to the seq file. */ 726 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr) 727 { 728 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr); 729 } 730 731 static void sctp_v6_ecn_capable(struct sock *sk) 732 { 733 inet6_sk(sk)->tclass |= INET_ECN_ECT_0; 734 } 735 736 /* Initialize a PF_INET msgname from a ulpevent. */ 737 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event, 738 char *msgname, int *addrlen) 739 { 740 union sctp_addr *addr; 741 struct sctp_association *asoc; 742 union sctp_addr *paddr; 743 744 if (!msgname) 745 return; 746 747 addr = (union sctp_addr *)msgname; 748 asoc = event->asoc; 749 paddr = &asoc->peer.primary_addr; 750 751 if (paddr->sa.sa_family == AF_INET) { 752 addr->v4.sin_family = AF_INET; 753 addr->v4.sin_port = htons(asoc->peer.port); 754 addr->v4.sin_addr = paddr->v4.sin_addr; 755 } else { 756 addr->v6.sin6_family = AF_INET6; 757 addr->v6.sin6_flowinfo = 0; 758 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 759 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id; 760 else 761 addr->v6.sin6_scope_id = 0; 762 addr->v6.sin6_port = htons(asoc->peer.port); 763 addr->v6.sin6_addr = paddr->v6.sin6_addr; 764 } 765 766 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr); 767 } 768 769 /* Initialize a msg_name from an inbound skb. */ 770 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname, 771 int *addr_len) 772 { 773 union sctp_addr *addr; 774 struct sctphdr *sh; 775 776 if (!msgname) 777 return; 778 779 addr = (union sctp_addr *)msgname; 780 sh = sctp_hdr(skb); 781 782 if (ip_hdr(skb)->version == 4) { 783 addr->v4.sin_family = AF_INET; 784 addr->v4.sin_port = sh->source; 785 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr; 786 } else { 787 addr->v6.sin6_family = AF_INET6; 788 addr->v6.sin6_flowinfo = 0; 789 addr->v6.sin6_port = sh->source; 790 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 791 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) { 792 addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb); 793 } 794 } 795 796 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr); 797 } 798 799 /* Do we support this AF? */ 800 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp) 801 { 802 switch (family) { 803 case AF_INET6: 804 return 1; 805 /* v4-mapped-v6 addresses */ 806 case AF_INET: 807 if (!__ipv6_only_sock(sctp_opt2sk(sp))) 808 return 1; 809 default: 810 return 0; 811 } 812 } 813 814 /* Address matching with wildcards allowed. This extra level 815 * of indirection lets us choose whether a PF_INET6 should 816 * disallow any v4 addresses if we so choose. 817 */ 818 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, 819 const union sctp_addr *addr2, 820 struct sctp_sock *opt) 821 { 822 struct sctp_af *af1, *af2; 823 struct sock *sk = sctp_opt2sk(opt); 824 825 af1 = sctp_get_af_specific(addr1->sa.sa_family); 826 af2 = sctp_get_af_specific(addr2->sa.sa_family); 827 828 if (!af1 || !af2) 829 return 0; 830 831 /* If the socket is IPv6 only, v4 addrs will not match */ 832 if (__ipv6_only_sock(sk) && af1 != af2) 833 return 0; 834 835 /* Today, wildcard AF_INET/AF_INET6. */ 836 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2)) 837 return 1; 838 839 if (addr1->sa.sa_family != addr2->sa.sa_family) 840 return 0; 841 842 return af1->cmp_addr(addr1, addr2); 843 } 844 845 /* Verify that the provided sockaddr looks bindable. Common verification, 846 * has already been taken care of. 847 */ 848 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr) 849 { 850 struct sctp_af *af; 851 852 /* ASSERT: address family has already been verified. */ 853 if (addr->sa.sa_family != AF_INET6) 854 af = sctp_get_af_specific(addr->sa.sa_family); 855 else { 856 int type = ipv6_addr_type(&addr->v6.sin6_addr); 857 struct net_device *dev; 858 859 if (type & IPV6_ADDR_LINKLOCAL) { 860 struct net *net; 861 if (!addr->v6.sin6_scope_id) 862 return 0; 863 net = sock_net(&opt->inet.sk); 864 rcu_read_lock(); 865 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id); 866 if (!dev || 867 !ipv6_chk_addr(net, &addr->v6.sin6_addr, dev, 0)) { 868 rcu_read_unlock(); 869 return 0; 870 } 871 rcu_read_unlock(); 872 } 873 874 af = opt->pf->af; 875 } 876 return af->available(addr, opt); 877 } 878 879 /* Verify that the provided sockaddr looks sendable. Common verification, 880 * has already been taken care of. 881 */ 882 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr) 883 { 884 struct sctp_af *af = NULL; 885 886 /* ASSERT: address family has already been verified. */ 887 if (addr->sa.sa_family != AF_INET6) 888 af = sctp_get_af_specific(addr->sa.sa_family); 889 else { 890 int type = ipv6_addr_type(&addr->v6.sin6_addr); 891 struct net_device *dev; 892 893 if (type & IPV6_ADDR_LINKLOCAL) { 894 if (!addr->v6.sin6_scope_id) 895 return 0; 896 rcu_read_lock(); 897 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk), 898 addr->v6.sin6_scope_id); 899 rcu_read_unlock(); 900 if (!dev) 901 return 0; 902 } 903 af = opt->pf->af; 904 } 905 906 return af != NULL; 907 } 908 909 /* Fill in Supported Address Type information for INIT and INIT-ACK 910 * chunks. Note: In the future, we may want to look at sock options 911 * to determine whether a PF_INET6 socket really wants to have IPV4 912 * addresses. 913 * Returns number of addresses supported. 914 */ 915 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt, 916 __be16 *types) 917 { 918 types[0] = SCTP_PARAM_IPV6_ADDRESS; 919 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) { 920 types[1] = SCTP_PARAM_IPV4_ADDRESS; 921 return 2; 922 } 923 return 1; 924 } 925 926 /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */ 927 static int sctp_getname(struct socket *sock, struct sockaddr *uaddr, 928 int *uaddr_len, int peer) 929 { 930 int rc; 931 932 rc = inet6_getname(sock, uaddr, uaddr_len, peer); 933 934 if (rc != 0) 935 return rc; 936 937 *uaddr_len = sctp_v6_addr_to_user(sctp_sk(sock->sk), 938 (union sctp_addr *)uaddr); 939 940 return rc; 941 } 942 943 static const struct proto_ops inet6_seqpacket_ops = { 944 .family = PF_INET6, 945 .owner = THIS_MODULE, 946 .release = inet6_release, 947 .bind = inet6_bind, 948 .connect = inet_dgram_connect, 949 .socketpair = sock_no_socketpair, 950 .accept = inet_accept, 951 .getname = sctp_getname, 952 .poll = sctp_poll, 953 .ioctl = inet6_ioctl, 954 .listen = sctp_inet_listen, 955 .shutdown = inet_shutdown, 956 .setsockopt = sock_common_setsockopt, 957 .getsockopt = sock_common_getsockopt, 958 .sendmsg = inet_sendmsg, 959 .recvmsg = inet_recvmsg, 960 .mmap = sock_no_mmap, 961 #ifdef CONFIG_COMPAT 962 .compat_setsockopt = compat_sock_common_setsockopt, 963 .compat_getsockopt = compat_sock_common_getsockopt, 964 #endif 965 }; 966 967 static struct inet_protosw sctpv6_seqpacket_protosw = { 968 .type = SOCK_SEQPACKET, 969 .protocol = IPPROTO_SCTP, 970 .prot = &sctpv6_prot, 971 .ops = &inet6_seqpacket_ops, 972 .flags = SCTP_PROTOSW_FLAG 973 }; 974 static struct inet_protosw sctpv6_stream_protosw = { 975 .type = SOCK_STREAM, 976 .protocol = IPPROTO_SCTP, 977 .prot = &sctpv6_prot, 978 .ops = &inet6_seqpacket_ops, 979 .flags = SCTP_PROTOSW_FLAG, 980 }; 981 982 static int sctp6_rcv(struct sk_buff *skb) 983 { 984 return sctp_rcv(skb) ? -1 : 0; 985 } 986 987 static const struct inet6_protocol sctpv6_protocol = { 988 .handler = sctp6_rcv, 989 .err_handler = sctp_v6_err, 990 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, 991 }; 992 993 static struct sctp_af sctp_af_inet6 = { 994 .sa_family = AF_INET6, 995 .sctp_xmit = sctp_v6_xmit, 996 .setsockopt = ipv6_setsockopt, 997 .getsockopt = ipv6_getsockopt, 998 .get_dst = sctp_v6_get_dst, 999 .get_saddr = sctp_v6_get_saddr, 1000 .copy_addrlist = sctp_v6_copy_addrlist, 1001 .from_skb = sctp_v6_from_skb, 1002 .from_sk = sctp_v6_from_sk, 1003 .from_addr_param = sctp_v6_from_addr_param, 1004 .to_addr_param = sctp_v6_to_addr_param, 1005 .cmp_addr = sctp_v6_cmp_addr, 1006 .scope = sctp_v6_scope, 1007 .addr_valid = sctp_v6_addr_valid, 1008 .inaddr_any = sctp_v6_inaddr_any, 1009 .is_any = sctp_v6_is_any, 1010 .available = sctp_v6_available, 1011 .skb_iif = sctp_v6_skb_iif, 1012 .is_ce = sctp_v6_is_ce, 1013 .seq_dump_addr = sctp_v6_seq_dump_addr, 1014 .ecn_capable = sctp_v6_ecn_capable, 1015 .net_header_len = sizeof(struct ipv6hdr), 1016 .sockaddr_len = sizeof(struct sockaddr_in6), 1017 #ifdef CONFIG_COMPAT 1018 .compat_setsockopt = compat_ipv6_setsockopt, 1019 .compat_getsockopt = compat_ipv6_getsockopt, 1020 #endif 1021 }; 1022 1023 static struct sctp_pf sctp_pf_inet6 = { 1024 .event_msgname = sctp_inet6_event_msgname, 1025 .skb_msgname = sctp_inet6_skb_msgname, 1026 .af_supported = sctp_inet6_af_supported, 1027 .cmp_addr = sctp_inet6_cmp_addr, 1028 .bind_verify = sctp_inet6_bind_verify, 1029 .send_verify = sctp_inet6_send_verify, 1030 .supported_addrs = sctp_inet6_supported_addrs, 1031 .create_accept_sk = sctp_v6_create_accept_sk, 1032 .addr_to_user = sctp_v6_addr_to_user, 1033 .to_sk_saddr = sctp_v6_to_sk_saddr, 1034 .to_sk_daddr = sctp_v6_to_sk_daddr, 1035 .af = &sctp_af_inet6, 1036 }; 1037 1038 /* Initialize IPv6 support and register with socket layer. */ 1039 void sctp_v6_pf_init(void) 1040 { 1041 /* Register the SCTP specific PF_INET6 functions. */ 1042 sctp_register_pf(&sctp_pf_inet6, PF_INET6); 1043 1044 /* Register the SCTP specific AF_INET6 functions. */ 1045 sctp_register_af(&sctp_af_inet6); 1046 } 1047 1048 void sctp_v6_pf_exit(void) 1049 { 1050 list_del(&sctp_af_inet6.list); 1051 } 1052 1053 /* Initialize IPv6 support and register with socket layer. */ 1054 int sctp_v6_protosw_init(void) 1055 { 1056 int rc; 1057 1058 rc = proto_register(&sctpv6_prot, 1); 1059 if (rc) 1060 return rc; 1061 1062 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */ 1063 inet6_register_protosw(&sctpv6_seqpacket_protosw); 1064 inet6_register_protosw(&sctpv6_stream_protosw); 1065 1066 return 0; 1067 } 1068 1069 void sctp_v6_protosw_exit(void) 1070 { 1071 inet6_unregister_protosw(&sctpv6_seqpacket_protosw); 1072 inet6_unregister_protosw(&sctpv6_stream_protosw); 1073 proto_unregister(&sctpv6_prot); 1074 } 1075 1076 1077 /* Register with inet6 layer. */ 1078 int sctp_v6_add_protocol(void) 1079 { 1080 /* Register notifier for inet6 address additions/deletions. */ 1081 register_inet6addr_notifier(&sctp_inet6addr_notifier); 1082 1083 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0) 1084 return -EAGAIN; 1085 1086 return 0; 1087 } 1088 1089 /* Unregister with inet6 layer. */ 1090 void sctp_v6_del_protocol(void) 1091 { 1092 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP); 1093 unregister_inet6addr_notifier(&sctp_inet6addr_notifier); 1094 } 1095