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; 212 213 pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb, 214 skb->len, &fl6->saddr, &fl6->daddr); 215 216 IP6_ECN_flow_xmit(sk, fl6->flowlabel); 217 218 if (!(transport->param_flags & SPP_PMTUD_ENABLE)) 219 skb->ignore_df = 1; 220 221 SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS); 222 223 return ip6_xmit(sk, skb, fl6, np->opt, np->tclass); 224 } 225 226 /* Returns the dst cache entry for the given source and destination ip 227 * addresses. 228 */ 229 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr, 230 struct flowi *fl, struct sock *sk) 231 { 232 struct sctp_association *asoc = t->asoc; 233 struct dst_entry *dst = NULL; 234 struct flowi6 *fl6 = &fl->u.ip6; 235 struct sctp_bind_addr *bp; 236 struct ipv6_pinfo *np = inet6_sk(sk); 237 struct sctp_sockaddr_entry *laddr; 238 union sctp_addr *baddr = NULL; 239 union sctp_addr *daddr = &t->ipaddr; 240 union sctp_addr dst_saddr; 241 struct in6_addr *final_p, final; 242 __u8 matchlen = 0; 243 __u8 bmatchlen; 244 sctp_scope_t scope; 245 246 memset(fl6, 0, sizeof(struct flowi6)); 247 fl6->daddr = daddr->v6.sin6_addr; 248 fl6->fl6_dport = daddr->v6.sin6_port; 249 fl6->flowi6_proto = IPPROTO_SCTP; 250 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 251 fl6->flowi6_oif = daddr->v6.sin6_scope_id; 252 253 pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr); 254 255 if (asoc) 256 fl6->fl6_sport = htons(asoc->base.bind_addr.port); 257 258 if (saddr) { 259 fl6->saddr = saddr->v6.sin6_addr; 260 fl6->fl6_sport = saddr->v6.sin6_port; 261 262 pr_debug("src=%pI6 - ", &fl6->saddr); 263 } 264 265 final_p = fl6_update_dst(fl6, np->opt, &final); 266 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 267 if (!asoc || saddr) 268 goto out; 269 270 bp = &asoc->base.bind_addr; 271 scope = sctp_scope(daddr); 272 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check 273 * to see if we can use it. 274 */ 275 if (!IS_ERR(dst)) { 276 /* Walk through the bind address list and look for a bind 277 * address that matches the source address of the returned dst. 278 */ 279 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port)); 280 rcu_read_lock(); 281 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 282 if (!laddr->valid || laddr->state == SCTP_ADDR_DEL || 283 (laddr->state != SCTP_ADDR_SRC && 284 !asoc->src_out_of_asoc_ok)) 285 continue; 286 287 /* Do not compare against v4 addrs */ 288 if ((laddr->a.sa.sa_family == AF_INET6) && 289 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) { 290 rcu_read_unlock(); 291 goto out; 292 } 293 } 294 rcu_read_unlock(); 295 /* None of the bound addresses match the source address of the 296 * dst. So release it. 297 */ 298 dst_release(dst); 299 dst = NULL; 300 } 301 302 /* Walk through the bind address list and try to get the 303 * best source address for a given destination. 304 */ 305 rcu_read_lock(); 306 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 307 if (!laddr->valid) 308 continue; 309 if ((laddr->state == SCTP_ADDR_SRC) && 310 (laddr->a.sa.sa_family == AF_INET6) && 311 (scope <= sctp_scope(&laddr->a))) { 312 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a); 313 if (!baddr || (matchlen < bmatchlen)) { 314 baddr = &laddr->a; 315 matchlen = bmatchlen; 316 } 317 } 318 } 319 rcu_read_unlock(); 320 321 if (baddr) { 322 fl6->saddr = baddr->v6.sin6_addr; 323 fl6->fl6_sport = baddr->v6.sin6_port; 324 final_p = fl6_update_dst(fl6, np->opt, &final); 325 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 326 } 327 328 out: 329 if (!IS_ERR_OR_NULL(dst)) { 330 struct rt6_info *rt; 331 332 rt = (struct rt6_info *)dst; 333 t->dst = dst; 334 t->dst_cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0; 335 pr_debug("rt6_dst:%pI6 rt6_src:%pI6\n", &rt->rt6i_dst.addr, 336 &fl6->saddr); 337 } else { 338 t->dst = NULL; 339 340 pr_debug("no route\n"); 341 } 342 } 343 344 /* Returns the number of consecutive initial bits that match in the 2 ipv6 345 * addresses. 346 */ 347 static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 348 union sctp_addr *s2) 349 { 350 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr); 351 } 352 353 /* Fills in the source address(saddr) based on the destination address(daddr) 354 * and asoc's bind address list. 355 */ 356 static void sctp_v6_get_saddr(struct sctp_sock *sk, 357 struct sctp_transport *t, 358 struct flowi *fl) 359 { 360 struct flowi6 *fl6 = &fl->u.ip6; 361 union sctp_addr *saddr = &t->saddr; 362 363 pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst); 364 365 if (t->dst) { 366 saddr->v6.sin6_family = AF_INET6; 367 saddr->v6.sin6_addr = fl6->saddr; 368 } 369 } 370 371 /* Make a copy of all potential local addresses. */ 372 static void sctp_v6_copy_addrlist(struct list_head *addrlist, 373 struct net_device *dev) 374 { 375 struct inet6_dev *in6_dev; 376 struct inet6_ifaddr *ifp; 377 struct sctp_sockaddr_entry *addr; 378 379 rcu_read_lock(); 380 if ((in6_dev = __in6_dev_get(dev)) == NULL) { 381 rcu_read_unlock(); 382 return; 383 } 384 385 read_lock_bh(&in6_dev->lock); 386 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) { 387 /* Add the address to the local list. */ 388 addr = kzalloc(sizeof(*addr), GFP_ATOMIC); 389 if (addr) { 390 addr->a.v6.sin6_family = AF_INET6; 391 addr->a.v6.sin6_port = 0; 392 addr->a.v6.sin6_addr = ifp->addr; 393 addr->a.v6.sin6_scope_id = dev->ifindex; 394 addr->valid = 1; 395 INIT_LIST_HEAD(&addr->list); 396 list_add_tail(&addr->list, addrlist); 397 } 398 } 399 400 read_unlock_bh(&in6_dev->lock); 401 rcu_read_unlock(); 402 } 403 404 /* Initialize a sockaddr_storage from in incoming skb. */ 405 static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb, 406 int is_saddr) 407 { 408 __be16 *port; 409 struct sctphdr *sh; 410 411 port = &addr->v6.sin6_port; 412 addr->v6.sin6_family = AF_INET6; 413 addr->v6.sin6_flowinfo = 0; /* FIXME */ 414 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif; 415 416 sh = sctp_hdr(skb); 417 if (is_saddr) { 418 *port = sh->source; 419 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 420 } else { 421 *port = sh->dest; 422 addr->v6.sin6_addr = ipv6_hdr(skb)->daddr; 423 } 424 } 425 426 /* Initialize an sctp_addr from a socket. */ 427 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk) 428 { 429 addr->v6.sin6_family = AF_INET6; 430 addr->v6.sin6_port = 0; 431 addr->v6.sin6_addr = sk->sk_v6_rcv_saddr; 432 } 433 434 /* Initialize sk->sk_rcv_saddr from sctp_addr. */ 435 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk) 436 { 437 if (addr->sa.sa_family == AF_INET) { 438 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0; 439 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0; 440 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff); 441 sk->sk_v6_rcv_saddr.s6_addr32[3] = 442 addr->v4.sin_addr.s_addr; 443 } else { 444 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr; 445 } 446 } 447 448 /* Initialize sk->sk_daddr from sctp_addr. */ 449 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk) 450 { 451 if (addr->sa.sa_family == AF_INET) { 452 sk->sk_v6_daddr.s6_addr32[0] = 0; 453 sk->sk_v6_daddr.s6_addr32[1] = 0; 454 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff); 455 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr; 456 } else { 457 sk->sk_v6_daddr = addr->v6.sin6_addr; 458 } 459 } 460 461 /* Initialize a sctp_addr from an address parameter. */ 462 static void sctp_v6_from_addr_param(union sctp_addr *addr, 463 union sctp_addr_param *param, 464 __be16 port, int iif) 465 { 466 addr->v6.sin6_family = AF_INET6; 467 addr->v6.sin6_port = port; 468 addr->v6.sin6_flowinfo = 0; /* BUG */ 469 addr->v6.sin6_addr = param->v6.addr; 470 addr->v6.sin6_scope_id = iif; 471 } 472 473 /* Initialize an address parameter from a sctp_addr and return the length 474 * of the address parameter. 475 */ 476 static int sctp_v6_to_addr_param(const union sctp_addr *addr, 477 union sctp_addr_param *param) 478 { 479 int length = sizeof(sctp_ipv6addr_param_t); 480 481 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS; 482 param->v6.param_hdr.length = htons(length); 483 param->v6.addr = addr->v6.sin6_addr; 484 485 return length; 486 } 487 488 /* Initialize a sctp_addr from struct in6_addr. */ 489 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 490 __be16 port) 491 { 492 addr->sa.sa_family = AF_INET6; 493 addr->v6.sin6_port = port; 494 addr->v6.sin6_addr = *saddr; 495 } 496 497 /* Compare addresses exactly. 498 * v4-mapped-v6 is also in consideration. 499 */ 500 static int sctp_v6_cmp_addr(const union sctp_addr *addr1, 501 const union sctp_addr *addr2) 502 { 503 if (addr1->sa.sa_family != addr2->sa.sa_family) { 504 if (addr1->sa.sa_family == AF_INET && 505 addr2->sa.sa_family == AF_INET6 && 506 ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) { 507 if (addr2->v6.sin6_port == addr1->v4.sin_port && 508 addr2->v6.sin6_addr.s6_addr32[3] == 509 addr1->v4.sin_addr.s_addr) 510 return 1; 511 } 512 if (addr2->sa.sa_family == AF_INET && 513 addr1->sa.sa_family == AF_INET6 && 514 ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) { 515 if (addr1->v6.sin6_port == addr2->v4.sin_port && 516 addr1->v6.sin6_addr.s6_addr32[3] == 517 addr2->v4.sin_addr.s_addr) 518 return 1; 519 } 520 return 0; 521 } 522 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr)) 523 return 0; 524 /* If this is a linklocal address, compare the scope_id. */ 525 if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) { 526 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id && 527 (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) { 528 return 0; 529 } 530 } 531 532 return 1; 533 } 534 535 /* Initialize addr struct to INADDR_ANY. */ 536 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port) 537 { 538 memset(addr, 0x00, sizeof(union sctp_addr)); 539 addr->v6.sin6_family = AF_INET6; 540 addr->v6.sin6_port = port; 541 } 542 543 /* Is this a wildcard address? */ 544 static int sctp_v6_is_any(const union sctp_addr *addr) 545 { 546 return ipv6_addr_any(&addr->v6.sin6_addr); 547 } 548 549 /* Should this be available for binding? */ 550 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp) 551 { 552 int type; 553 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr; 554 555 type = ipv6_addr_type(in6); 556 if (IPV6_ADDR_ANY == type) 557 return 1; 558 if (type == IPV6_ADDR_MAPPED) { 559 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 560 return 0; 561 sctp_v6_map_v4(addr); 562 return sctp_get_af_specific(AF_INET)->available(addr, sp); 563 } 564 if (!(type & IPV6_ADDR_UNICAST)) 565 return 0; 566 567 return ipv6_chk_addr(sock_net(&sp->inet.sk), in6, NULL, 0); 568 } 569 570 /* This function checks if the address is a valid address to be used for 571 * SCTP. 572 * 573 * Output: 574 * Return 0 - If the address is a non-unicast or an illegal address. 575 * Return 1 - If the address is a unicast. 576 */ 577 static int sctp_v6_addr_valid(union sctp_addr *addr, 578 struct sctp_sock *sp, 579 const struct sk_buff *skb) 580 { 581 int ret = ipv6_addr_type(&addr->v6.sin6_addr); 582 583 /* Support v4-mapped-v6 address. */ 584 if (ret == IPV6_ADDR_MAPPED) { 585 /* Note: This routine is used in input, so v4-mapped-v6 586 * are disallowed here when there is no sctp_sock. 587 */ 588 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 589 return 0; 590 sctp_v6_map_v4(addr); 591 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb); 592 } 593 594 /* Is this a non-unicast address */ 595 if (!(ret & IPV6_ADDR_UNICAST)) 596 return 0; 597 598 return 1; 599 } 600 601 /* What is the scope of 'addr'? */ 602 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr) 603 { 604 int v6scope; 605 sctp_scope_t retval; 606 607 /* The IPv6 scope is really a set of bit fields. 608 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope. 609 */ 610 611 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr); 612 switch (v6scope) { 613 case IFA_HOST: 614 retval = SCTP_SCOPE_LOOPBACK; 615 break; 616 case IFA_LINK: 617 retval = SCTP_SCOPE_LINK; 618 break; 619 case IFA_SITE: 620 retval = SCTP_SCOPE_PRIVATE; 621 break; 622 default: 623 retval = SCTP_SCOPE_GLOBAL; 624 break; 625 } 626 627 return retval; 628 } 629 630 /* Create and initialize a new sk for the socket to be returned by accept(). */ 631 static struct sock *sctp_v6_create_accept_sk(struct sock *sk, 632 struct sctp_association *asoc) 633 { 634 struct sock *newsk; 635 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 636 struct sctp6_sock *newsctp6sk; 637 638 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot); 639 if (!newsk) 640 goto out; 641 642 sock_init_data(NULL, newsk); 643 644 sctp_copy_sock(newsk, sk, asoc); 645 sock_reset_flag(sk, SOCK_ZAPPED); 646 647 newsctp6sk = (struct sctp6_sock *)newsk; 648 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6; 649 650 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped; 651 652 newnp = inet6_sk(newsk); 653 654 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 655 656 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() 657 * and getpeername(). 658 */ 659 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk); 660 661 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr; 662 663 sk_refcnt_debug_inc(newsk); 664 665 if (newsk->sk_prot->init(newsk)) { 666 sk_common_release(newsk); 667 newsk = NULL; 668 } 669 670 out: 671 return newsk; 672 } 673 674 /* Format a sockaddr for return to user space. This makes sure the return is 675 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. 676 */ 677 static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr) 678 { 679 if (sp->v4mapped) { 680 if (addr->sa.sa_family == AF_INET) 681 sctp_v4_map_v6(addr); 682 } else { 683 if (addr->sa.sa_family == AF_INET6 && 684 ipv6_addr_v4mapped(&addr->v6.sin6_addr)) 685 sctp_v6_map_v4(addr); 686 } 687 688 if (addr->sa.sa_family == AF_INET) 689 return sizeof(struct sockaddr_in); 690 return sizeof(struct sockaddr_in6); 691 } 692 693 /* Where did this skb come from? */ 694 static int sctp_v6_skb_iif(const struct sk_buff *skb) 695 { 696 struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb; 697 return opt->iif; 698 } 699 700 /* Was this packet marked by Explicit Congestion Notification? */ 701 static int sctp_v6_is_ce(const struct sk_buff *skb) 702 { 703 return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20); 704 } 705 706 /* Dump the v6 addr to the seq file. */ 707 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr) 708 { 709 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr); 710 } 711 712 static void sctp_v6_ecn_capable(struct sock *sk) 713 { 714 inet6_sk(sk)->tclass |= INET_ECN_ECT_0; 715 } 716 717 /* Initialize a PF_INET msgname from a ulpevent. */ 718 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event, 719 char *msgname, int *addrlen) 720 { 721 union sctp_addr *addr; 722 struct sctp_association *asoc; 723 union sctp_addr *paddr; 724 725 if (!msgname) 726 return; 727 728 addr = (union sctp_addr *)msgname; 729 asoc = event->asoc; 730 paddr = &asoc->peer.primary_addr; 731 732 if (paddr->sa.sa_family == AF_INET) { 733 addr->v4.sin_family = AF_INET; 734 addr->v4.sin_port = htons(asoc->peer.port); 735 addr->v4.sin_addr = paddr->v4.sin_addr; 736 } else { 737 addr->v6.sin6_family = AF_INET6; 738 addr->v6.sin6_flowinfo = 0; 739 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 740 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id; 741 else 742 addr->v6.sin6_scope_id = 0; 743 addr->v6.sin6_port = htons(asoc->peer.port); 744 addr->v6.sin6_addr = paddr->v6.sin6_addr; 745 } 746 747 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr); 748 } 749 750 /* Initialize a msg_name from an inbound skb. */ 751 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname, 752 int *addr_len) 753 { 754 union sctp_addr *addr; 755 struct sctphdr *sh; 756 757 if (!msgname) 758 return; 759 760 addr = (union sctp_addr *)msgname; 761 sh = sctp_hdr(skb); 762 763 if (ip_hdr(skb)->version == 4) { 764 addr->v4.sin_family = AF_INET; 765 addr->v4.sin_port = sh->source; 766 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr; 767 } else { 768 addr->v6.sin6_family = AF_INET6; 769 addr->v6.sin6_flowinfo = 0; 770 addr->v6.sin6_port = sh->source; 771 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 772 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) { 773 struct sctp_ulpevent *ev = sctp_skb2event(skb); 774 addr->v6.sin6_scope_id = ev->iif; 775 } 776 } 777 778 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr); 779 } 780 781 /* Do we support this AF? */ 782 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp) 783 { 784 switch (family) { 785 case AF_INET6: 786 return 1; 787 /* v4-mapped-v6 addresses */ 788 case AF_INET: 789 if (!__ipv6_only_sock(sctp_opt2sk(sp))) 790 return 1; 791 default: 792 return 0; 793 } 794 } 795 796 /* Address matching with wildcards allowed. This extra level 797 * of indirection lets us choose whether a PF_INET6 should 798 * disallow any v4 addresses if we so choose. 799 */ 800 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, 801 const union sctp_addr *addr2, 802 struct sctp_sock *opt) 803 { 804 struct sctp_af *af1, *af2; 805 struct sock *sk = sctp_opt2sk(opt); 806 807 af1 = sctp_get_af_specific(addr1->sa.sa_family); 808 af2 = sctp_get_af_specific(addr2->sa.sa_family); 809 810 if (!af1 || !af2) 811 return 0; 812 813 /* If the socket is IPv6 only, v4 addrs will not match */ 814 if (__ipv6_only_sock(sk) && af1 != af2) 815 return 0; 816 817 /* Today, wildcard AF_INET/AF_INET6. */ 818 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2)) 819 return 1; 820 821 if (addr1->sa.sa_family != addr2->sa.sa_family) 822 return 0; 823 824 return af1->cmp_addr(addr1, addr2); 825 } 826 827 /* Verify that the provided sockaddr looks bindable. Common verification, 828 * has already been taken care of. 829 */ 830 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr) 831 { 832 struct sctp_af *af; 833 834 /* ASSERT: address family has already been verified. */ 835 if (addr->sa.sa_family != AF_INET6) 836 af = sctp_get_af_specific(addr->sa.sa_family); 837 else { 838 int type = ipv6_addr_type(&addr->v6.sin6_addr); 839 struct net_device *dev; 840 841 if (type & IPV6_ADDR_LINKLOCAL) { 842 struct net *net; 843 if (!addr->v6.sin6_scope_id) 844 return 0; 845 net = sock_net(&opt->inet.sk); 846 rcu_read_lock(); 847 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id); 848 if (!dev || 849 !ipv6_chk_addr(net, &addr->v6.sin6_addr, dev, 0)) { 850 rcu_read_unlock(); 851 return 0; 852 } 853 rcu_read_unlock(); 854 } 855 856 af = opt->pf->af; 857 } 858 return af->available(addr, opt); 859 } 860 861 /* Verify that the provided sockaddr looks sendable. Common verification, 862 * has already been taken care of. 863 */ 864 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr) 865 { 866 struct sctp_af *af = NULL; 867 868 /* ASSERT: address family has already been verified. */ 869 if (addr->sa.sa_family != AF_INET6) 870 af = sctp_get_af_specific(addr->sa.sa_family); 871 else { 872 int type = ipv6_addr_type(&addr->v6.sin6_addr); 873 struct net_device *dev; 874 875 if (type & IPV6_ADDR_LINKLOCAL) { 876 if (!addr->v6.sin6_scope_id) 877 return 0; 878 rcu_read_lock(); 879 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk), 880 addr->v6.sin6_scope_id); 881 rcu_read_unlock(); 882 if (!dev) 883 return 0; 884 } 885 af = opt->pf->af; 886 } 887 888 return af != NULL; 889 } 890 891 /* Fill in Supported Address Type information for INIT and INIT-ACK 892 * chunks. Note: In the future, we may want to look at sock options 893 * to determine whether a PF_INET6 socket really wants to have IPV4 894 * addresses. 895 * Returns number of addresses supported. 896 */ 897 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt, 898 __be16 *types) 899 { 900 types[0] = SCTP_PARAM_IPV6_ADDRESS; 901 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) { 902 types[1] = SCTP_PARAM_IPV4_ADDRESS; 903 return 2; 904 } 905 return 1; 906 } 907 908 /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */ 909 static int sctp_getname(struct socket *sock, struct sockaddr *uaddr, 910 int *uaddr_len, int peer) 911 { 912 int rc; 913 914 rc = inet6_getname(sock, uaddr, uaddr_len, peer); 915 916 if (rc != 0) 917 return rc; 918 919 *uaddr_len = sctp_v6_addr_to_user(sctp_sk(sock->sk), 920 (union sctp_addr *)uaddr); 921 922 return rc; 923 } 924 925 static const struct proto_ops inet6_seqpacket_ops = { 926 .family = PF_INET6, 927 .owner = THIS_MODULE, 928 .release = inet6_release, 929 .bind = inet6_bind, 930 .connect = inet_dgram_connect, 931 .socketpair = sock_no_socketpair, 932 .accept = inet_accept, 933 .getname = sctp_getname, 934 .poll = sctp_poll, 935 .ioctl = inet6_ioctl, 936 .listen = sctp_inet_listen, 937 .shutdown = inet_shutdown, 938 .setsockopt = sock_common_setsockopt, 939 .getsockopt = sock_common_getsockopt, 940 .sendmsg = inet_sendmsg, 941 .recvmsg = sock_common_recvmsg, 942 .mmap = sock_no_mmap, 943 #ifdef CONFIG_COMPAT 944 .compat_setsockopt = compat_sock_common_setsockopt, 945 .compat_getsockopt = compat_sock_common_getsockopt, 946 #endif 947 }; 948 949 static struct inet_protosw sctpv6_seqpacket_protosw = { 950 .type = SOCK_SEQPACKET, 951 .protocol = IPPROTO_SCTP, 952 .prot = &sctpv6_prot, 953 .ops = &inet6_seqpacket_ops, 954 .flags = SCTP_PROTOSW_FLAG 955 }; 956 static struct inet_protosw sctpv6_stream_protosw = { 957 .type = SOCK_STREAM, 958 .protocol = IPPROTO_SCTP, 959 .prot = &sctpv6_prot, 960 .ops = &inet6_seqpacket_ops, 961 .flags = SCTP_PROTOSW_FLAG, 962 }; 963 964 static int sctp6_rcv(struct sk_buff *skb) 965 { 966 return sctp_rcv(skb) ? -1 : 0; 967 } 968 969 static const struct inet6_protocol sctpv6_protocol = { 970 .handler = sctp6_rcv, 971 .err_handler = sctp_v6_err, 972 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, 973 }; 974 975 static struct sctp_af sctp_af_inet6 = { 976 .sa_family = AF_INET6, 977 .sctp_xmit = sctp_v6_xmit, 978 .setsockopt = ipv6_setsockopt, 979 .getsockopt = ipv6_getsockopt, 980 .get_dst = sctp_v6_get_dst, 981 .get_saddr = sctp_v6_get_saddr, 982 .copy_addrlist = sctp_v6_copy_addrlist, 983 .from_skb = sctp_v6_from_skb, 984 .from_sk = sctp_v6_from_sk, 985 .from_addr_param = sctp_v6_from_addr_param, 986 .to_addr_param = sctp_v6_to_addr_param, 987 .cmp_addr = sctp_v6_cmp_addr, 988 .scope = sctp_v6_scope, 989 .addr_valid = sctp_v6_addr_valid, 990 .inaddr_any = sctp_v6_inaddr_any, 991 .is_any = sctp_v6_is_any, 992 .available = sctp_v6_available, 993 .skb_iif = sctp_v6_skb_iif, 994 .is_ce = sctp_v6_is_ce, 995 .seq_dump_addr = sctp_v6_seq_dump_addr, 996 .ecn_capable = sctp_v6_ecn_capable, 997 .net_header_len = sizeof(struct ipv6hdr), 998 .sockaddr_len = sizeof(struct sockaddr_in6), 999 #ifdef CONFIG_COMPAT 1000 .compat_setsockopt = compat_ipv6_setsockopt, 1001 .compat_getsockopt = compat_ipv6_getsockopt, 1002 #endif 1003 }; 1004 1005 static struct sctp_pf sctp_pf_inet6 = { 1006 .event_msgname = sctp_inet6_event_msgname, 1007 .skb_msgname = sctp_inet6_skb_msgname, 1008 .af_supported = sctp_inet6_af_supported, 1009 .cmp_addr = sctp_inet6_cmp_addr, 1010 .bind_verify = sctp_inet6_bind_verify, 1011 .send_verify = sctp_inet6_send_verify, 1012 .supported_addrs = sctp_inet6_supported_addrs, 1013 .create_accept_sk = sctp_v6_create_accept_sk, 1014 .addr_to_user = sctp_v6_addr_to_user, 1015 .to_sk_saddr = sctp_v6_to_sk_saddr, 1016 .to_sk_daddr = sctp_v6_to_sk_daddr, 1017 .af = &sctp_af_inet6, 1018 }; 1019 1020 /* Initialize IPv6 support and register with socket layer. */ 1021 void sctp_v6_pf_init(void) 1022 { 1023 /* Register the SCTP specific PF_INET6 functions. */ 1024 sctp_register_pf(&sctp_pf_inet6, PF_INET6); 1025 1026 /* Register the SCTP specific AF_INET6 functions. */ 1027 sctp_register_af(&sctp_af_inet6); 1028 } 1029 1030 void sctp_v6_pf_exit(void) 1031 { 1032 list_del(&sctp_af_inet6.list); 1033 } 1034 1035 /* Initialize IPv6 support and register with socket layer. */ 1036 int sctp_v6_protosw_init(void) 1037 { 1038 int rc; 1039 1040 rc = proto_register(&sctpv6_prot, 1); 1041 if (rc) 1042 return rc; 1043 1044 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */ 1045 inet6_register_protosw(&sctpv6_seqpacket_protosw); 1046 inet6_register_protosw(&sctpv6_stream_protosw); 1047 1048 return 0; 1049 } 1050 1051 void sctp_v6_protosw_exit(void) 1052 { 1053 inet6_unregister_protosw(&sctpv6_seqpacket_protosw); 1054 inet6_unregister_protosw(&sctpv6_stream_protosw); 1055 proto_unregister(&sctpv6_prot); 1056 } 1057 1058 1059 /* Register with inet6 layer. */ 1060 int sctp_v6_add_protocol(void) 1061 { 1062 /* Register notifier for inet6 address additions/deletions. */ 1063 register_inet6addr_notifier(&sctp_inet6addr_notifier); 1064 1065 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0) 1066 return -EAGAIN; 1067 1068 return 0; 1069 } 1070 1071 /* Unregister with inet6 layer. */ 1072 void sctp_v6_del_protocol(void) 1073 { 1074 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP); 1075 unregister_inet6addr_notifier(&sctp_inet6addr_notifier); 1076 } 1077