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 *daddr = &t->ipaddr; 244 union sctp_addr dst_saddr; 245 struct in6_addr *final_p, final; 246 enum sctp_scope scope; 247 __u8 matchlen = 0; 248 249 memset(fl6, 0, sizeof(struct flowi6)); 250 fl6->daddr = daddr->v6.sin6_addr; 251 fl6->fl6_dport = daddr->v6.sin6_port; 252 fl6->flowi6_proto = IPPROTO_SCTP; 253 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 254 fl6->flowi6_oif = daddr->v6.sin6_scope_id; 255 else if (asoc) 256 fl6->flowi6_oif = asoc->base.sk->sk_bound_dev_if; 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 struct dst_entry *bdst; 316 __u8 bmatchlen; 317 318 if (!laddr->valid || 319 laddr->state != SCTP_ADDR_SRC || 320 laddr->a.sa.sa_family != AF_INET6 || 321 scope > sctp_scope(&laddr->a)) 322 continue; 323 324 fl6->saddr = laddr->a.v6.sin6_addr; 325 fl6->fl6_sport = laddr->a.v6.sin6_port; 326 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 327 bdst = ip6_dst_lookup_flow(sk, fl6, final_p); 328 329 if (IS_ERR(bdst)) 330 continue; 331 332 if (ipv6_chk_addr(dev_net(bdst->dev), 333 &laddr->a.v6.sin6_addr, bdst->dev, 1)) { 334 if (!IS_ERR_OR_NULL(dst)) 335 dst_release(dst); 336 dst = bdst; 337 break; 338 } 339 340 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a); 341 if (matchlen > bmatchlen) { 342 dst_release(bdst); 343 continue; 344 } 345 346 if (!IS_ERR_OR_NULL(dst)) 347 dst_release(dst); 348 dst = bdst; 349 matchlen = bmatchlen; 350 } 351 rcu_read_unlock(); 352 353 out: 354 if (!IS_ERR_OR_NULL(dst)) { 355 struct rt6_info *rt; 356 357 rt = (struct rt6_info *)dst; 358 t->dst = dst; 359 t->dst_cookie = rt6_get_cookie(rt); 360 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n", 361 &rt->rt6i_dst.addr, rt->rt6i_dst.plen, 362 &fl6->saddr); 363 } else { 364 t->dst = NULL; 365 366 pr_debug("no route\n"); 367 } 368 } 369 370 /* Returns the number of consecutive initial bits that match in the 2 ipv6 371 * addresses. 372 */ 373 static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 374 union sctp_addr *s2) 375 { 376 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr); 377 } 378 379 /* Fills in the source address(saddr) based on the destination address(daddr) 380 * and asoc's bind address list. 381 */ 382 static void sctp_v6_get_saddr(struct sctp_sock *sk, 383 struct sctp_transport *t, 384 struct flowi *fl) 385 { 386 struct flowi6 *fl6 = &fl->u.ip6; 387 union sctp_addr *saddr = &t->saddr; 388 389 pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst); 390 391 if (t->dst) { 392 saddr->v6.sin6_family = AF_INET6; 393 saddr->v6.sin6_addr = fl6->saddr; 394 } 395 } 396 397 /* Make a copy of all potential local addresses. */ 398 static void sctp_v6_copy_addrlist(struct list_head *addrlist, 399 struct net_device *dev) 400 { 401 struct inet6_dev *in6_dev; 402 struct inet6_ifaddr *ifp; 403 struct sctp_sockaddr_entry *addr; 404 405 rcu_read_lock(); 406 if ((in6_dev = __in6_dev_get(dev)) == NULL) { 407 rcu_read_unlock(); 408 return; 409 } 410 411 read_lock_bh(&in6_dev->lock); 412 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) { 413 /* Add the address to the local list. */ 414 addr = kzalloc(sizeof(*addr), GFP_ATOMIC); 415 if (addr) { 416 addr->a.v6.sin6_family = AF_INET6; 417 addr->a.v6.sin6_port = 0; 418 addr->a.v6.sin6_addr = ifp->addr; 419 addr->a.v6.sin6_scope_id = dev->ifindex; 420 addr->valid = 1; 421 INIT_LIST_HEAD(&addr->list); 422 list_add_tail(&addr->list, addrlist); 423 } 424 } 425 426 read_unlock_bh(&in6_dev->lock); 427 rcu_read_unlock(); 428 } 429 430 /* Initialize a sockaddr_storage from in incoming skb. */ 431 static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb, 432 int is_saddr) 433 { 434 /* Always called on head skb, so this is safe */ 435 struct sctphdr *sh = sctp_hdr(skb); 436 struct sockaddr_in6 *sa = &addr->v6; 437 438 addr->v6.sin6_family = AF_INET6; 439 addr->v6.sin6_flowinfo = 0; /* FIXME */ 440 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif; 441 442 if (is_saddr) { 443 sa->sin6_port = sh->source; 444 sa->sin6_addr = ipv6_hdr(skb)->saddr; 445 } else { 446 sa->sin6_port = sh->dest; 447 sa->sin6_addr = ipv6_hdr(skb)->daddr; 448 } 449 } 450 451 /* Initialize an sctp_addr from a socket. */ 452 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk) 453 { 454 addr->v6.sin6_family = AF_INET6; 455 addr->v6.sin6_port = 0; 456 addr->v6.sin6_addr = sk->sk_v6_rcv_saddr; 457 } 458 459 /* Initialize sk->sk_rcv_saddr from sctp_addr. */ 460 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk) 461 { 462 if (addr->sa.sa_family == AF_INET) { 463 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0; 464 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0; 465 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff); 466 sk->sk_v6_rcv_saddr.s6_addr32[3] = 467 addr->v4.sin_addr.s_addr; 468 } else { 469 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr; 470 } 471 } 472 473 /* Initialize sk->sk_daddr from sctp_addr. */ 474 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk) 475 { 476 if (addr->sa.sa_family == AF_INET) { 477 sk->sk_v6_daddr.s6_addr32[0] = 0; 478 sk->sk_v6_daddr.s6_addr32[1] = 0; 479 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff); 480 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr; 481 } else { 482 sk->sk_v6_daddr = addr->v6.sin6_addr; 483 } 484 } 485 486 /* Initialize a sctp_addr from an address parameter. */ 487 static void sctp_v6_from_addr_param(union sctp_addr *addr, 488 union sctp_addr_param *param, 489 __be16 port, int iif) 490 { 491 addr->v6.sin6_family = AF_INET6; 492 addr->v6.sin6_port = port; 493 addr->v6.sin6_flowinfo = 0; /* BUG */ 494 addr->v6.sin6_addr = param->v6.addr; 495 addr->v6.sin6_scope_id = iif; 496 } 497 498 /* Initialize an address parameter from a sctp_addr and return the length 499 * of the address parameter. 500 */ 501 static int sctp_v6_to_addr_param(const union sctp_addr *addr, 502 union sctp_addr_param *param) 503 { 504 int length = sizeof(struct sctp_ipv6addr_param); 505 506 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS; 507 param->v6.param_hdr.length = htons(length); 508 param->v6.addr = addr->v6.sin6_addr; 509 510 return length; 511 } 512 513 /* Initialize a sctp_addr from struct in6_addr. */ 514 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 515 __be16 port) 516 { 517 addr->sa.sa_family = AF_INET6; 518 addr->v6.sin6_port = port; 519 addr->v6.sin6_flowinfo = 0; 520 addr->v6.sin6_addr = *saddr; 521 addr->v6.sin6_scope_id = 0; 522 } 523 524 /* Compare addresses exactly. 525 * v4-mapped-v6 is also in consideration. 526 */ 527 static int sctp_v6_cmp_addr(const union sctp_addr *addr1, 528 const union sctp_addr *addr2) 529 { 530 if (addr1->sa.sa_family != addr2->sa.sa_family) { 531 if (addr1->sa.sa_family == AF_INET && 532 addr2->sa.sa_family == AF_INET6 && 533 ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) { 534 if (addr2->v6.sin6_port == addr1->v4.sin_port && 535 addr2->v6.sin6_addr.s6_addr32[3] == 536 addr1->v4.sin_addr.s_addr) 537 return 1; 538 } 539 if (addr2->sa.sa_family == AF_INET && 540 addr1->sa.sa_family == AF_INET6 && 541 ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) { 542 if (addr1->v6.sin6_port == addr2->v4.sin_port && 543 addr1->v6.sin6_addr.s6_addr32[3] == 544 addr2->v4.sin_addr.s_addr) 545 return 1; 546 } 547 return 0; 548 } 549 if (addr1->v6.sin6_port != addr2->v6.sin6_port) 550 return 0; 551 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr)) 552 return 0; 553 /* If this is a linklocal address, compare the scope_id. */ 554 if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) { 555 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id && 556 (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) { 557 return 0; 558 } 559 } 560 561 return 1; 562 } 563 564 /* Initialize addr struct to INADDR_ANY. */ 565 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port) 566 { 567 memset(addr, 0x00, sizeof(union sctp_addr)); 568 addr->v6.sin6_family = AF_INET6; 569 addr->v6.sin6_port = port; 570 } 571 572 /* Is this a wildcard address? */ 573 static int sctp_v6_is_any(const union sctp_addr *addr) 574 { 575 return ipv6_addr_any(&addr->v6.sin6_addr); 576 } 577 578 /* Should this be available for binding? */ 579 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp) 580 { 581 int type; 582 struct net *net = sock_net(&sp->inet.sk); 583 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr; 584 585 type = ipv6_addr_type(in6); 586 if (IPV6_ADDR_ANY == type) 587 return 1; 588 if (type == IPV6_ADDR_MAPPED) { 589 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 590 return 0; 591 sctp_v6_map_v4(addr); 592 return sctp_get_af_specific(AF_INET)->available(addr, sp); 593 } 594 if (!(type & IPV6_ADDR_UNICAST)) 595 return 0; 596 597 return sp->inet.freebind || net->ipv6.sysctl.ip_nonlocal_bind || 598 ipv6_chk_addr(net, in6, NULL, 0); 599 } 600 601 /* This function checks if the address is a valid address to be used for 602 * SCTP. 603 * 604 * Output: 605 * Return 0 - If the address is a non-unicast or an illegal address. 606 * Return 1 - If the address is a unicast. 607 */ 608 static int sctp_v6_addr_valid(union sctp_addr *addr, 609 struct sctp_sock *sp, 610 const struct sk_buff *skb) 611 { 612 int ret = ipv6_addr_type(&addr->v6.sin6_addr); 613 614 /* Support v4-mapped-v6 address. */ 615 if (ret == IPV6_ADDR_MAPPED) { 616 /* Note: This routine is used in input, so v4-mapped-v6 617 * are disallowed here when there is no sctp_sock. 618 */ 619 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 620 return 0; 621 sctp_v6_map_v4(addr); 622 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb); 623 } 624 625 /* Is this a non-unicast address */ 626 if (!(ret & IPV6_ADDR_UNICAST)) 627 return 0; 628 629 return 1; 630 } 631 632 /* What is the scope of 'addr'? */ 633 static enum sctp_scope sctp_v6_scope(union sctp_addr *addr) 634 { 635 enum sctp_scope retval; 636 int v6scope; 637 638 /* The IPv6 scope is really a set of bit fields. 639 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope. 640 */ 641 642 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr); 643 switch (v6scope) { 644 case IFA_HOST: 645 retval = SCTP_SCOPE_LOOPBACK; 646 break; 647 case IFA_LINK: 648 retval = SCTP_SCOPE_LINK; 649 break; 650 case IFA_SITE: 651 retval = SCTP_SCOPE_PRIVATE; 652 break; 653 default: 654 retval = SCTP_SCOPE_GLOBAL; 655 break; 656 } 657 658 return retval; 659 } 660 661 /* Create and initialize a new sk for the socket to be returned by accept(). */ 662 static struct sock *sctp_v6_create_accept_sk(struct sock *sk, 663 struct sctp_association *asoc, 664 bool kern) 665 { 666 struct sock *newsk; 667 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 668 struct sctp6_sock *newsctp6sk; 669 struct ipv6_txoptions *opt; 670 671 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern); 672 if (!newsk) 673 goto out; 674 675 sock_init_data(NULL, newsk); 676 677 sctp_copy_sock(newsk, sk, asoc); 678 sock_reset_flag(sk, SOCK_ZAPPED); 679 680 newsctp6sk = (struct sctp6_sock *)newsk; 681 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6; 682 683 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped; 684 685 newnp = inet6_sk(newsk); 686 687 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 688 newnp->ipv6_mc_list = NULL; 689 newnp->ipv6_ac_list = NULL; 690 newnp->ipv6_fl_list = NULL; 691 692 rcu_read_lock(); 693 opt = rcu_dereference(np->opt); 694 if (opt) 695 opt = ipv6_dup_options(newsk, opt); 696 RCU_INIT_POINTER(newnp->opt, opt); 697 rcu_read_unlock(); 698 699 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() 700 * and getpeername(). 701 */ 702 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk); 703 704 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr; 705 706 sk_refcnt_debug_inc(newsk); 707 708 if (newsk->sk_prot->init(newsk)) { 709 sk_common_release(newsk); 710 newsk = NULL; 711 } 712 713 out: 714 return newsk; 715 } 716 717 /* Format a sockaddr for return to user space. This makes sure the return is 718 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. 719 */ 720 static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr) 721 { 722 if (sp->v4mapped) { 723 if (addr->sa.sa_family == AF_INET) 724 sctp_v4_map_v6(addr); 725 } else { 726 if (addr->sa.sa_family == AF_INET6 && 727 ipv6_addr_v4mapped(&addr->v6.sin6_addr)) 728 sctp_v6_map_v4(addr); 729 } 730 731 if (addr->sa.sa_family == AF_INET) 732 return sizeof(struct sockaddr_in); 733 return sizeof(struct sockaddr_in6); 734 } 735 736 /* Where did this skb come from? */ 737 static int sctp_v6_skb_iif(const struct sk_buff *skb) 738 { 739 return IP6CB(skb)->iif; 740 } 741 742 /* Was this packet marked by Explicit Congestion Notification? */ 743 static int sctp_v6_is_ce(const struct sk_buff *skb) 744 { 745 return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20); 746 } 747 748 /* Dump the v6 addr to the seq file. */ 749 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr) 750 { 751 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr); 752 } 753 754 static void sctp_v6_ecn_capable(struct sock *sk) 755 { 756 inet6_sk(sk)->tclass |= INET_ECN_ECT_0; 757 } 758 759 /* Initialize a PF_INET msgname from a ulpevent. */ 760 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event, 761 char *msgname, int *addrlen) 762 { 763 union sctp_addr *addr; 764 struct sctp_association *asoc; 765 union sctp_addr *paddr; 766 767 if (!msgname) 768 return; 769 770 addr = (union sctp_addr *)msgname; 771 asoc = event->asoc; 772 paddr = &asoc->peer.primary_addr; 773 774 if (paddr->sa.sa_family == AF_INET) { 775 addr->v4.sin_family = AF_INET; 776 addr->v4.sin_port = htons(asoc->peer.port); 777 addr->v4.sin_addr = paddr->v4.sin_addr; 778 } else { 779 addr->v6.sin6_family = AF_INET6; 780 addr->v6.sin6_flowinfo = 0; 781 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 782 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id; 783 else 784 addr->v6.sin6_scope_id = 0; 785 addr->v6.sin6_port = htons(asoc->peer.port); 786 addr->v6.sin6_addr = paddr->v6.sin6_addr; 787 } 788 789 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr); 790 } 791 792 /* Initialize a msg_name from an inbound skb. */ 793 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname, 794 int *addr_len) 795 { 796 union sctp_addr *addr; 797 struct sctphdr *sh; 798 799 if (!msgname) 800 return; 801 802 addr = (union sctp_addr *)msgname; 803 sh = sctp_hdr(skb); 804 805 if (ip_hdr(skb)->version == 4) { 806 addr->v4.sin_family = AF_INET; 807 addr->v4.sin_port = sh->source; 808 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr; 809 } else { 810 addr->v6.sin6_family = AF_INET6; 811 addr->v6.sin6_flowinfo = 0; 812 addr->v6.sin6_port = sh->source; 813 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 814 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 815 addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb); 816 else 817 addr->v6.sin6_scope_id = 0; 818 } 819 820 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr); 821 } 822 823 /* Do we support this AF? */ 824 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp) 825 { 826 switch (family) { 827 case AF_INET6: 828 return 1; 829 /* v4-mapped-v6 addresses */ 830 case AF_INET: 831 if (!__ipv6_only_sock(sctp_opt2sk(sp))) 832 return 1; 833 /* fallthru */ 834 default: 835 return 0; 836 } 837 } 838 839 /* Address matching with wildcards allowed. This extra level 840 * of indirection lets us choose whether a PF_INET6 should 841 * disallow any v4 addresses if we so choose. 842 */ 843 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, 844 const union sctp_addr *addr2, 845 struct sctp_sock *opt) 846 { 847 struct sctp_af *af1, *af2; 848 struct sock *sk = sctp_opt2sk(opt); 849 850 af1 = sctp_get_af_specific(addr1->sa.sa_family); 851 af2 = sctp_get_af_specific(addr2->sa.sa_family); 852 853 if (!af1 || !af2) 854 return 0; 855 856 /* If the socket is IPv6 only, v4 addrs will not match */ 857 if (__ipv6_only_sock(sk) && af1 != af2) 858 return 0; 859 860 /* Today, wildcard AF_INET/AF_INET6. */ 861 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2)) 862 return 1; 863 864 if (addr1->sa.sa_family != addr2->sa.sa_family) 865 return 0; 866 867 return af1->cmp_addr(addr1, addr2); 868 } 869 870 /* Verify that the provided sockaddr looks bindable. Common verification, 871 * has already been taken care of. 872 */ 873 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr) 874 { 875 struct sctp_af *af; 876 877 /* ASSERT: address family has already been verified. */ 878 if (addr->sa.sa_family != AF_INET6) 879 af = sctp_get_af_specific(addr->sa.sa_family); 880 else { 881 int type = ipv6_addr_type(&addr->v6.sin6_addr); 882 struct net_device *dev; 883 884 if (type & IPV6_ADDR_LINKLOCAL) { 885 struct net *net; 886 if (!addr->v6.sin6_scope_id) 887 return 0; 888 net = sock_net(&opt->inet.sk); 889 rcu_read_lock(); 890 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id); 891 if (!dev || !(opt->inet.freebind || 892 net->ipv6.sysctl.ip_nonlocal_bind || 893 ipv6_chk_addr(net, &addr->v6.sin6_addr, 894 dev, 0))) { 895 rcu_read_unlock(); 896 return 0; 897 } 898 rcu_read_unlock(); 899 } 900 901 af = opt->pf->af; 902 } 903 return af->available(addr, opt); 904 } 905 906 /* Verify that the provided sockaddr looks sendable. Common verification, 907 * has already been taken care of. 908 */ 909 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr) 910 { 911 struct sctp_af *af = NULL; 912 913 /* ASSERT: address family has already been verified. */ 914 if (addr->sa.sa_family != AF_INET6) 915 af = sctp_get_af_specific(addr->sa.sa_family); 916 else { 917 int type = ipv6_addr_type(&addr->v6.sin6_addr); 918 struct net_device *dev; 919 920 if (type & IPV6_ADDR_LINKLOCAL) { 921 if (!addr->v6.sin6_scope_id) 922 return 0; 923 rcu_read_lock(); 924 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk), 925 addr->v6.sin6_scope_id); 926 rcu_read_unlock(); 927 if (!dev) 928 return 0; 929 } 930 af = opt->pf->af; 931 } 932 933 return af != NULL; 934 } 935 936 /* Fill in Supported Address Type information for INIT and INIT-ACK 937 * chunks. Note: In the future, we may want to look at sock options 938 * to determine whether a PF_INET6 socket really wants to have IPV4 939 * addresses. 940 * Returns number of addresses supported. 941 */ 942 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt, 943 __be16 *types) 944 { 945 types[0] = SCTP_PARAM_IPV6_ADDRESS; 946 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) { 947 types[1] = SCTP_PARAM_IPV4_ADDRESS; 948 return 2; 949 } 950 return 1; 951 } 952 953 /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */ 954 static int sctp_getname(struct socket *sock, struct sockaddr *uaddr, 955 int *uaddr_len, int peer) 956 { 957 int rc; 958 959 rc = inet6_getname(sock, uaddr, uaddr_len, peer); 960 961 if (rc != 0) 962 return rc; 963 964 *uaddr_len = sctp_v6_addr_to_user(sctp_sk(sock->sk), 965 (union sctp_addr *)uaddr); 966 967 return rc; 968 } 969 970 static const struct proto_ops inet6_seqpacket_ops = { 971 .family = PF_INET6, 972 .owner = THIS_MODULE, 973 .release = inet6_release, 974 .bind = inet6_bind, 975 .connect = inet_dgram_connect, 976 .socketpair = sock_no_socketpair, 977 .accept = inet_accept, 978 .getname = sctp_getname, 979 .poll = sctp_poll, 980 .ioctl = inet6_ioctl, 981 .listen = sctp_inet_listen, 982 .shutdown = inet_shutdown, 983 .setsockopt = sock_common_setsockopt, 984 .getsockopt = sock_common_getsockopt, 985 .sendmsg = inet_sendmsg, 986 .recvmsg = inet_recvmsg, 987 .mmap = sock_no_mmap, 988 #ifdef CONFIG_COMPAT 989 .compat_setsockopt = compat_sock_common_setsockopt, 990 .compat_getsockopt = compat_sock_common_getsockopt, 991 #endif 992 }; 993 994 static struct inet_protosw sctpv6_seqpacket_protosw = { 995 .type = SOCK_SEQPACKET, 996 .protocol = IPPROTO_SCTP, 997 .prot = &sctpv6_prot, 998 .ops = &inet6_seqpacket_ops, 999 .flags = SCTP_PROTOSW_FLAG 1000 }; 1001 static struct inet_protosw sctpv6_stream_protosw = { 1002 .type = SOCK_STREAM, 1003 .protocol = IPPROTO_SCTP, 1004 .prot = &sctpv6_prot, 1005 .ops = &inet6_seqpacket_ops, 1006 .flags = SCTP_PROTOSW_FLAG, 1007 }; 1008 1009 static int sctp6_rcv(struct sk_buff *skb) 1010 { 1011 return sctp_rcv(skb) ? -1 : 0; 1012 } 1013 1014 static const struct inet6_protocol sctpv6_protocol = { 1015 .handler = sctp6_rcv, 1016 .err_handler = sctp_v6_err, 1017 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, 1018 }; 1019 1020 static struct sctp_af sctp_af_inet6 = { 1021 .sa_family = AF_INET6, 1022 .sctp_xmit = sctp_v6_xmit, 1023 .setsockopt = ipv6_setsockopt, 1024 .getsockopt = ipv6_getsockopt, 1025 .get_dst = sctp_v6_get_dst, 1026 .get_saddr = sctp_v6_get_saddr, 1027 .copy_addrlist = sctp_v6_copy_addrlist, 1028 .from_skb = sctp_v6_from_skb, 1029 .from_sk = sctp_v6_from_sk, 1030 .from_addr_param = sctp_v6_from_addr_param, 1031 .to_addr_param = sctp_v6_to_addr_param, 1032 .cmp_addr = sctp_v6_cmp_addr, 1033 .scope = sctp_v6_scope, 1034 .addr_valid = sctp_v6_addr_valid, 1035 .inaddr_any = sctp_v6_inaddr_any, 1036 .is_any = sctp_v6_is_any, 1037 .available = sctp_v6_available, 1038 .skb_iif = sctp_v6_skb_iif, 1039 .is_ce = sctp_v6_is_ce, 1040 .seq_dump_addr = sctp_v6_seq_dump_addr, 1041 .ecn_capable = sctp_v6_ecn_capable, 1042 .net_header_len = sizeof(struct ipv6hdr), 1043 .sockaddr_len = sizeof(struct sockaddr_in6), 1044 #ifdef CONFIG_COMPAT 1045 .compat_setsockopt = compat_ipv6_setsockopt, 1046 .compat_getsockopt = compat_ipv6_getsockopt, 1047 #endif 1048 }; 1049 1050 static struct sctp_pf sctp_pf_inet6 = { 1051 .event_msgname = sctp_inet6_event_msgname, 1052 .skb_msgname = sctp_inet6_skb_msgname, 1053 .af_supported = sctp_inet6_af_supported, 1054 .cmp_addr = sctp_inet6_cmp_addr, 1055 .bind_verify = sctp_inet6_bind_verify, 1056 .send_verify = sctp_inet6_send_verify, 1057 .supported_addrs = sctp_inet6_supported_addrs, 1058 .create_accept_sk = sctp_v6_create_accept_sk, 1059 .addr_to_user = sctp_v6_addr_to_user, 1060 .to_sk_saddr = sctp_v6_to_sk_saddr, 1061 .to_sk_daddr = sctp_v6_to_sk_daddr, 1062 .af = &sctp_af_inet6, 1063 }; 1064 1065 /* Initialize IPv6 support and register with socket layer. */ 1066 void sctp_v6_pf_init(void) 1067 { 1068 /* Register the SCTP specific PF_INET6 functions. */ 1069 sctp_register_pf(&sctp_pf_inet6, PF_INET6); 1070 1071 /* Register the SCTP specific AF_INET6 functions. */ 1072 sctp_register_af(&sctp_af_inet6); 1073 } 1074 1075 void sctp_v6_pf_exit(void) 1076 { 1077 list_del(&sctp_af_inet6.list); 1078 } 1079 1080 /* Initialize IPv6 support and register with socket layer. */ 1081 int sctp_v6_protosw_init(void) 1082 { 1083 int rc; 1084 1085 rc = proto_register(&sctpv6_prot, 1); 1086 if (rc) 1087 return rc; 1088 1089 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */ 1090 inet6_register_protosw(&sctpv6_seqpacket_protosw); 1091 inet6_register_protosw(&sctpv6_stream_protosw); 1092 1093 return 0; 1094 } 1095 1096 void sctp_v6_protosw_exit(void) 1097 { 1098 inet6_unregister_protosw(&sctpv6_seqpacket_protosw); 1099 inet6_unregister_protosw(&sctpv6_stream_protosw); 1100 proto_unregister(&sctpv6_prot); 1101 } 1102 1103 1104 /* Register with inet6 layer. */ 1105 int sctp_v6_add_protocol(void) 1106 { 1107 /* Register notifier for inet6 address additions/deletions. */ 1108 register_inet6addr_notifier(&sctp_inet6addr_notifier); 1109 1110 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0) 1111 return -EAGAIN; 1112 1113 return 0; 1114 } 1115 1116 /* Unregister with inet6 layer. */ 1117 void sctp_v6_del_protocol(void) 1118 { 1119 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP); 1120 unregister_inet6addr_notifier(&sctp_inet6addr_notifier); 1121 } 1122