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_BH(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 rcu_read_unlock(); 327 328 if (baddr) { 329 fl6->saddr = baddr->v6.sin6_addr; 330 fl6->fl6_sport = baddr->v6.sin6_port; 331 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 332 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 333 } 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 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 (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr)) 531 return 0; 532 /* If this is a linklocal address, compare the scope_id. */ 533 if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) { 534 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id && 535 (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) { 536 return 0; 537 } 538 } 539 540 return 1; 541 } 542 543 /* Initialize addr struct to INADDR_ANY. */ 544 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port) 545 { 546 memset(addr, 0x00, sizeof(union sctp_addr)); 547 addr->v6.sin6_family = AF_INET6; 548 addr->v6.sin6_port = port; 549 } 550 551 /* Is this a wildcard address? */ 552 static int sctp_v6_is_any(const union sctp_addr *addr) 553 { 554 return ipv6_addr_any(&addr->v6.sin6_addr); 555 } 556 557 /* Should this be available for binding? */ 558 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp) 559 { 560 int type; 561 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr; 562 563 type = ipv6_addr_type(in6); 564 if (IPV6_ADDR_ANY == type) 565 return 1; 566 if (type == IPV6_ADDR_MAPPED) { 567 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 568 return 0; 569 sctp_v6_map_v4(addr); 570 return sctp_get_af_specific(AF_INET)->available(addr, sp); 571 } 572 if (!(type & IPV6_ADDR_UNICAST)) 573 return 0; 574 575 return ipv6_chk_addr(sock_net(&sp->inet.sk), in6, NULL, 0); 576 } 577 578 /* This function checks if the address is a valid address to be used for 579 * SCTP. 580 * 581 * Output: 582 * Return 0 - If the address is a non-unicast or an illegal address. 583 * Return 1 - If the address is a unicast. 584 */ 585 static int sctp_v6_addr_valid(union sctp_addr *addr, 586 struct sctp_sock *sp, 587 const struct sk_buff *skb) 588 { 589 int ret = ipv6_addr_type(&addr->v6.sin6_addr); 590 591 /* Support v4-mapped-v6 address. */ 592 if (ret == IPV6_ADDR_MAPPED) { 593 /* Note: This routine is used in input, so v4-mapped-v6 594 * are disallowed here when there is no sctp_sock. 595 */ 596 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 597 return 0; 598 sctp_v6_map_v4(addr); 599 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb); 600 } 601 602 /* Is this a non-unicast address */ 603 if (!(ret & IPV6_ADDR_UNICAST)) 604 return 0; 605 606 return 1; 607 } 608 609 /* What is the scope of 'addr'? */ 610 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr) 611 { 612 int v6scope; 613 sctp_scope_t retval; 614 615 /* The IPv6 scope is really a set of bit fields. 616 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope. 617 */ 618 619 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr); 620 switch (v6scope) { 621 case IFA_HOST: 622 retval = SCTP_SCOPE_LOOPBACK; 623 break; 624 case IFA_LINK: 625 retval = SCTP_SCOPE_LINK; 626 break; 627 case IFA_SITE: 628 retval = SCTP_SCOPE_PRIVATE; 629 break; 630 default: 631 retval = SCTP_SCOPE_GLOBAL; 632 break; 633 } 634 635 return retval; 636 } 637 638 /* Create and initialize a new sk for the socket to be returned by accept(). */ 639 static struct sock *sctp_v6_create_accept_sk(struct sock *sk, 640 struct sctp_association *asoc) 641 { 642 struct sock *newsk; 643 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 644 struct sctp6_sock *newsctp6sk; 645 646 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, 0); 647 if (!newsk) 648 goto out; 649 650 sock_init_data(NULL, newsk); 651 652 sctp_copy_sock(newsk, sk, asoc); 653 sock_reset_flag(sk, SOCK_ZAPPED); 654 655 newsctp6sk = (struct sctp6_sock *)newsk; 656 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6; 657 658 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped; 659 660 newnp = inet6_sk(newsk); 661 662 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 663 664 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() 665 * and getpeername(). 666 */ 667 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk); 668 669 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr; 670 671 sk_refcnt_debug_inc(newsk); 672 673 if (newsk->sk_prot->init(newsk)) { 674 sk_common_release(newsk); 675 newsk = NULL; 676 } 677 678 out: 679 return newsk; 680 } 681 682 /* Format a sockaddr for return to user space. This makes sure the return is 683 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. 684 */ 685 static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr) 686 { 687 if (sp->v4mapped) { 688 if (addr->sa.sa_family == AF_INET) 689 sctp_v4_map_v6(addr); 690 } else { 691 if (addr->sa.sa_family == AF_INET6 && 692 ipv6_addr_v4mapped(&addr->v6.sin6_addr)) 693 sctp_v6_map_v4(addr); 694 } 695 696 if (addr->sa.sa_family == AF_INET) 697 return sizeof(struct sockaddr_in); 698 return sizeof(struct sockaddr_in6); 699 } 700 701 /* Where did this skb come from? */ 702 static int sctp_v6_skb_iif(const struct sk_buff *skb) 703 { 704 struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb; 705 return opt->iif; 706 } 707 708 /* Was this packet marked by Explicit Congestion Notification? */ 709 static int sctp_v6_is_ce(const struct sk_buff *skb) 710 { 711 return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20); 712 } 713 714 /* Dump the v6 addr to the seq file. */ 715 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr) 716 { 717 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr); 718 } 719 720 static void sctp_v6_ecn_capable(struct sock *sk) 721 { 722 inet6_sk(sk)->tclass |= INET_ECN_ECT_0; 723 } 724 725 /* Initialize a PF_INET msgname from a ulpevent. */ 726 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event, 727 char *msgname, int *addrlen) 728 { 729 union sctp_addr *addr; 730 struct sctp_association *asoc; 731 union sctp_addr *paddr; 732 733 if (!msgname) 734 return; 735 736 addr = (union sctp_addr *)msgname; 737 asoc = event->asoc; 738 paddr = &asoc->peer.primary_addr; 739 740 if (paddr->sa.sa_family == AF_INET) { 741 addr->v4.sin_family = AF_INET; 742 addr->v4.sin_port = htons(asoc->peer.port); 743 addr->v4.sin_addr = paddr->v4.sin_addr; 744 } else { 745 addr->v6.sin6_family = AF_INET6; 746 addr->v6.sin6_flowinfo = 0; 747 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 748 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id; 749 else 750 addr->v6.sin6_scope_id = 0; 751 addr->v6.sin6_port = htons(asoc->peer.port); 752 addr->v6.sin6_addr = paddr->v6.sin6_addr; 753 } 754 755 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr); 756 } 757 758 /* Initialize a msg_name from an inbound skb. */ 759 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname, 760 int *addr_len) 761 { 762 union sctp_addr *addr; 763 struct sctphdr *sh; 764 765 if (!msgname) 766 return; 767 768 addr = (union sctp_addr *)msgname; 769 sh = sctp_hdr(skb); 770 771 if (ip_hdr(skb)->version == 4) { 772 addr->v4.sin_family = AF_INET; 773 addr->v4.sin_port = sh->source; 774 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr; 775 } else { 776 addr->v6.sin6_family = AF_INET6; 777 addr->v6.sin6_flowinfo = 0; 778 addr->v6.sin6_port = sh->source; 779 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 780 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) { 781 struct sctp_ulpevent *ev = sctp_skb2event(skb); 782 addr->v6.sin6_scope_id = ev->iif; 783 } 784 } 785 786 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr); 787 } 788 789 /* Do we support this AF? */ 790 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp) 791 { 792 switch (family) { 793 case AF_INET6: 794 return 1; 795 /* v4-mapped-v6 addresses */ 796 case AF_INET: 797 if (!__ipv6_only_sock(sctp_opt2sk(sp))) 798 return 1; 799 default: 800 return 0; 801 } 802 } 803 804 /* Address matching with wildcards allowed. This extra level 805 * of indirection lets us choose whether a PF_INET6 should 806 * disallow any v4 addresses if we so choose. 807 */ 808 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, 809 const union sctp_addr *addr2, 810 struct sctp_sock *opt) 811 { 812 struct sctp_af *af1, *af2; 813 struct sock *sk = sctp_opt2sk(opt); 814 815 af1 = sctp_get_af_specific(addr1->sa.sa_family); 816 af2 = sctp_get_af_specific(addr2->sa.sa_family); 817 818 if (!af1 || !af2) 819 return 0; 820 821 /* If the socket is IPv6 only, v4 addrs will not match */ 822 if (__ipv6_only_sock(sk) && af1 != af2) 823 return 0; 824 825 /* Today, wildcard AF_INET/AF_INET6. */ 826 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2)) 827 return 1; 828 829 if (addr1->sa.sa_family != addr2->sa.sa_family) 830 return 0; 831 832 return af1->cmp_addr(addr1, addr2); 833 } 834 835 /* Verify that the provided sockaddr looks bindable. Common verification, 836 * has already been taken care of. 837 */ 838 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr) 839 { 840 struct sctp_af *af; 841 842 /* ASSERT: address family has already been verified. */ 843 if (addr->sa.sa_family != AF_INET6) 844 af = sctp_get_af_specific(addr->sa.sa_family); 845 else { 846 int type = ipv6_addr_type(&addr->v6.sin6_addr); 847 struct net_device *dev; 848 849 if (type & IPV6_ADDR_LINKLOCAL) { 850 struct net *net; 851 if (!addr->v6.sin6_scope_id) 852 return 0; 853 net = sock_net(&opt->inet.sk); 854 rcu_read_lock(); 855 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id); 856 if (!dev || 857 !ipv6_chk_addr(net, &addr->v6.sin6_addr, dev, 0)) { 858 rcu_read_unlock(); 859 return 0; 860 } 861 rcu_read_unlock(); 862 } 863 864 af = opt->pf->af; 865 } 866 return af->available(addr, opt); 867 } 868 869 /* Verify that the provided sockaddr looks sendable. Common verification, 870 * has already been taken care of. 871 */ 872 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr) 873 { 874 struct sctp_af *af = NULL; 875 876 /* ASSERT: address family has already been verified. */ 877 if (addr->sa.sa_family != AF_INET6) 878 af = sctp_get_af_specific(addr->sa.sa_family); 879 else { 880 int type = ipv6_addr_type(&addr->v6.sin6_addr); 881 struct net_device *dev; 882 883 if (type & IPV6_ADDR_LINKLOCAL) { 884 if (!addr->v6.sin6_scope_id) 885 return 0; 886 rcu_read_lock(); 887 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk), 888 addr->v6.sin6_scope_id); 889 rcu_read_unlock(); 890 if (!dev) 891 return 0; 892 } 893 af = opt->pf->af; 894 } 895 896 return af != NULL; 897 } 898 899 /* Fill in Supported Address Type information for INIT and INIT-ACK 900 * chunks. Note: In the future, we may want to look at sock options 901 * to determine whether a PF_INET6 socket really wants to have IPV4 902 * addresses. 903 * Returns number of addresses supported. 904 */ 905 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt, 906 __be16 *types) 907 { 908 types[0] = SCTP_PARAM_IPV6_ADDRESS; 909 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) { 910 types[1] = SCTP_PARAM_IPV4_ADDRESS; 911 return 2; 912 } 913 return 1; 914 } 915 916 /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */ 917 static int sctp_getname(struct socket *sock, struct sockaddr *uaddr, 918 int *uaddr_len, int peer) 919 { 920 int rc; 921 922 rc = inet6_getname(sock, uaddr, uaddr_len, peer); 923 924 if (rc != 0) 925 return rc; 926 927 *uaddr_len = sctp_v6_addr_to_user(sctp_sk(sock->sk), 928 (union sctp_addr *)uaddr); 929 930 return rc; 931 } 932 933 static const struct proto_ops inet6_seqpacket_ops = { 934 .family = PF_INET6, 935 .owner = THIS_MODULE, 936 .release = inet6_release, 937 .bind = inet6_bind, 938 .connect = inet_dgram_connect, 939 .socketpair = sock_no_socketpair, 940 .accept = inet_accept, 941 .getname = sctp_getname, 942 .poll = sctp_poll, 943 .ioctl = inet6_ioctl, 944 .listen = sctp_inet_listen, 945 .shutdown = inet_shutdown, 946 .setsockopt = sock_common_setsockopt, 947 .getsockopt = sock_common_getsockopt, 948 .sendmsg = inet_sendmsg, 949 .recvmsg = sock_common_recvmsg, 950 .mmap = sock_no_mmap, 951 #ifdef CONFIG_COMPAT 952 .compat_setsockopt = compat_sock_common_setsockopt, 953 .compat_getsockopt = compat_sock_common_getsockopt, 954 #endif 955 }; 956 957 static struct inet_protosw sctpv6_seqpacket_protosw = { 958 .type = SOCK_SEQPACKET, 959 .protocol = IPPROTO_SCTP, 960 .prot = &sctpv6_prot, 961 .ops = &inet6_seqpacket_ops, 962 .flags = SCTP_PROTOSW_FLAG 963 }; 964 static struct inet_protosw sctpv6_stream_protosw = { 965 .type = SOCK_STREAM, 966 .protocol = IPPROTO_SCTP, 967 .prot = &sctpv6_prot, 968 .ops = &inet6_seqpacket_ops, 969 .flags = SCTP_PROTOSW_FLAG, 970 }; 971 972 static int sctp6_rcv(struct sk_buff *skb) 973 { 974 return sctp_rcv(skb) ? -1 : 0; 975 } 976 977 static const struct inet6_protocol sctpv6_protocol = { 978 .handler = sctp6_rcv, 979 .err_handler = sctp_v6_err, 980 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, 981 }; 982 983 static struct sctp_af sctp_af_inet6 = { 984 .sa_family = AF_INET6, 985 .sctp_xmit = sctp_v6_xmit, 986 .setsockopt = ipv6_setsockopt, 987 .getsockopt = ipv6_getsockopt, 988 .get_dst = sctp_v6_get_dst, 989 .get_saddr = sctp_v6_get_saddr, 990 .copy_addrlist = sctp_v6_copy_addrlist, 991 .from_skb = sctp_v6_from_skb, 992 .from_sk = sctp_v6_from_sk, 993 .from_addr_param = sctp_v6_from_addr_param, 994 .to_addr_param = sctp_v6_to_addr_param, 995 .cmp_addr = sctp_v6_cmp_addr, 996 .scope = sctp_v6_scope, 997 .addr_valid = sctp_v6_addr_valid, 998 .inaddr_any = sctp_v6_inaddr_any, 999 .is_any = sctp_v6_is_any, 1000 .available = sctp_v6_available, 1001 .skb_iif = sctp_v6_skb_iif, 1002 .is_ce = sctp_v6_is_ce, 1003 .seq_dump_addr = sctp_v6_seq_dump_addr, 1004 .ecn_capable = sctp_v6_ecn_capable, 1005 .net_header_len = sizeof(struct ipv6hdr), 1006 .sockaddr_len = sizeof(struct sockaddr_in6), 1007 #ifdef CONFIG_COMPAT 1008 .compat_setsockopt = compat_ipv6_setsockopt, 1009 .compat_getsockopt = compat_ipv6_getsockopt, 1010 #endif 1011 }; 1012 1013 static struct sctp_pf sctp_pf_inet6 = { 1014 .event_msgname = sctp_inet6_event_msgname, 1015 .skb_msgname = sctp_inet6_skb_msgname, 1016 .af_supported = sctp_inet6_af_supported, 1017 .cmp_addr = sctp_inet6_cmp_addr, 1018 .bind_verify = sctp_inet6_bind_verify, 1019 .send_verify = sctp_inet6_send_verify, 1020 .supported_addrs = sctp_inet6_supported_addrs, 1021 .create_accept_sk = sctp_v6_create_accept_sk, 1022 .addr_to_user = sctp_v6_addr_to_user, 1023 .to_sk_saddr = sctp_v6_to_sk_saddr, 1024 .to_sk_daddr = sctp_v6_to_sk_daddr, 1025 .af = &sctp_af_inet6, 1026 }; 1027 1028 /* Initialize IPv6 support and register with socket layer. */ 1029 void sctp_v6_pf_init(void) 1030 { 1031 /* Register the SCTP specific PF_INET6 functions. */ 1032 sctp_register_pf(&sctp_pf_inet6, PF_INET6); 1033 1034 /* Register the SCTP specific AF_INET6 functions. */ 1035 sctp_register_af(&sctp_af_inet6); 1036 } 1037 1038 void sctp_v6_pf_exit(void) 1039 { 1040 list_del(&sctp_af_inet6.list); 1041 } 1042 1043 /* Initialize IPv6 support and register with socket layer. */ 1044 int sctp_v6_protosw_init(void) 1045 { 1046 int rc; 1047 1048 rc = proto_register(&sctpv6_prot, 1); 1049 if (rc) 1050 return rc; 1051 1052 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */ 1053 inet6_register_protosw(&sctpv6_seqpacket_protosw); 1054 inet6_register_protosw(&sctpv6_stream_protosw); 1055 1056 return 0; 1057 } 1058 1059 void sctp_v6_protosw_exit(void) 1060 { 1061 inet6_unregister_protosw(&sctpv6_seqpacket_protosw); 1062 inet6_unregister_protosw(&sctpv6_stream_protosw); 1063 proto_unregister(&sctpv6_prot); 1064 } 1065 1066 1067 /* Register with inet6 layer. */ 1068 int sctp_v6_add_protocol(void) 1069 { 1070 /* Register notifier for inet6 address additions/deletions. */ 1071 register_inet6addr_notifier(&sctp_inet6addr_notifier); 1072 1073 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0) 1074 return -EAGAIN; 1075 1076 return 0; 1077 } 1078 1079 /* Unregister with inet6 layer. */ 1080 void sctp_v6_del_protocol(void) 1081 { 1082 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP); 1083 unregister_inet6addr_notifier(&sctp_inet6addr_notifier); 1084 } 1085