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, write to 25 * the Free Software Foundation, 59 Temple Place - Suite 330, 26 * Boston, MA 02111-1307, USA. 27 * 28 * Please send any bug reports or fixes you make to the 29 * email address(es): 30 * lksctp developers <lksctp-developers@lists.sourceforge.net> 31 * 32 * Or submit a bug report through the following website: 33 * http://www.sf.net/projects/lksctp 34 * 35 * Written or modified by: 36 * Le Yanqun <yanqun.le@nokia.com> 37 * Hui Huang <hui.huang@nokia.com> 38 * La Monte H.P. Yarroll <piggy@acm.org> 39 * Sridhar Samudrala <sri@us.ibm.com> 40 * Jon Grimm <jgrimm@us.ibm.com> 41 * Ardelle Fan <ardelle.fan@intel.com> 42 * 43 * Based on: 44 * linux/net/ipv6/tcp_ipv6.c 45 * 46 * Any bugs reported given to us we will try to fix... any fixes shared will 47 * be incorporated into the next SCTP release. 48 */ 49 50 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 51 52 #include <linux/module.h> 53 #include <linux/errno.h> 54 #include <linux/types.h> 55 #include <linux/socket.h> 56 #include <linux/sockios.h> 57 #include <linux/net.h> 58 #include <linux/in.h> 59 #include <linux/in6.h> 60 #include <linux/netdevice.h> 61 #include <linux/init.h> 62 #include <linux/ipsec.h> 63 #include <linux/slab.h> 64 65 #include <linux/ipv6.h> 66 #include <linux/icmpv6.h> 67 #include <linux/random.h> 68 #include <linux/seq_file.h> 69 70 #include <net/protocol.h> 71 #include <net/ndisc.h> 72 #include <net/ip.h> 73 #include <net/ipv6.h> 74 #include <net/transp_v6.h> 75 #include <net/addrconf.h> 76 #include <net/ip6_route.h> 77 #include <net/inet_common.h> 78 #include <net/inet_ecn.h> 79 #include <net/sctp/sctp.h> 80 81 #include <asm/uaccess.h> 82 83 static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 84 union sctp_addr *s2); 85 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 86 __be16 port); 87 static int sctp_v6_cmp_addr(const union sctp_addr *addr1, 88 const union sctp_addr *addr2); 89 90 /* Event handler for inet6 address addition/deletion events. 91 * The sctp_local_addr_list needs to be protocted by a spin lock since 92 * multiple notifiers (say IPv4 and IPv6) may be running at the same 93 * time and thus corrupt the list. 94 * The reader side is protected with RCU. 95 */ 96 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev, 97 void *ptr) 98 { 99 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr; 100 struct sctp_sockaddr_entry *addr = NULL; 101 struct sctp_sockaddr_entry *temp; 102 int found = 0; 103 104 switch (ev) { 105 case NETDEV_UP: 106 addr = kmalloc(sizeof(struct sctp_sockaddr_entry), GFP_ATOMIC); 107 if (addr) { 108 addr->a.v6.sin6_family = AF_INET6; 109 addr->a.v6.sin6_port = 0; 110 addr->a.v6.sin6_addr = ifa->addr; 111 addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex; 112 addr->valid = 1; 113 spin_lock_bh(&sctp_local_addr_lock); 114 list_add_tail_rcu(&addr->list, &sctp_local_addr_list); 115 sctp_addr_wq_mgmt(addr, SCTP_ADDR_NEW); 116 spin_unlock_bh(&sctp_local_addr_lock); 117 } 118 break; 119 case NETDEV_DOWN: 120 spin_lock_bh(&sctp_local_addr_lock); 121 list_for_each_entry_safe(addr, temp, 122 &sctp_local_addr_list, list) { 123 if (addr->a.sa.sa_family == AF_INET6 && 124 ipv6_addr_equal(&addr->a.v6.sin6_addr, 125 &ifa->addr)) { 126 sctp_addr_wq_mgmt(addr, SCTP_ADDR_DEL); 127 found = 1; 128 addr->valid = 0; 129 list_del_rcu(&addr->list); 130 break; 131 } 132 } 133 spin_unlock_bh(&sctp_local_addr_lock); 134 if (found) 135 kfree_rcu(addr, rcu); 136 break; 137 } 138 139 return NOTIFY_DONE; 140 } 141 142 static struct notifier_block sctp_inet6addr_notifier = { 143 .notifier_call = sctp_inet6addr_event, 144 }; 145 146 /* ICMP error handler. */ 147 SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 148 u8 type, u8 code, int offset, __be32 info) 149 { 150 struct inet6_dev *idev; 151 struct sock *sk; 152 struct sctp_association *asoc; 153 struct sctp_transport *transport; 154 struct ipv6_pinfo *np; 155 sk_buff_data_t saveip, savesctp; 156 int err; 157 158 idev = in6_dev_get(skb->dev); 159 160 /* Fix up skb to look at the embedded net header. */ 161 saveip = skb->network_header; 162 savesctp = skb->transport_header; 163 skb_reset_network_header(skb); 164 skb_set_transport_header(skb, offset); 165 sk = sctp_err_lookup(AF_INET6, skb, sctp_hdr(skb), &asoc, &transport); 166 /* Put back, the original pointers. */ 167 skb->network_header = saveip; 168 skb->transport_header = savesctp; 169 if (!sk) { 170 ICMP6_INC_STATS_BH(dev_net(skb->dev), idev, ICMP6_MIB_INERRORS); 171 goto out; 172 } 173 174 /* Warning: The sock lock is held. Remember to call 175 * sctp_err_finish! 176 */ 177 178 switch (type) { 179 case ICMPV6_PKT_TOOBIG: 180 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info)); 181 goto out_unlock; 182 case ICMPV6_PARAMPROB: 183 if (ICMPV6_UNK_NEXTHDR == code) { 184 sctp_icmp_proto_unreachable(sk, asoc, transport); 185 goto out_unlock; 186 } 187 break; 188 default: 189 break; 190 } 191 192 np = inet6_sk(sk); 193 icmpv6_err_convert(type, code, &err); 194 if (!sock_owned_by_user(sk) && np->recverr) { 195 sk->sk_err = err; 196 sk->sk_error_report(sk); 197 } else { /* Only an error on timeout */ 198 sk->sk_err_soft = err; 199 } 200 201 out_unlock: 202 sctp_err_finish(sk, asoc); 203 out: 204 if (likely(idev != NULL)) 205 in6_dev_put(idev); 206 } 207 208 /* Based on tcp_v6_xmit() in tcp_ipv6.c. */ 209 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport) 210 { 211 struct sock *sk = skb->sk; 212 struct ipv6_pinfo *np = inet6_sk(sk); 213 struct flowi6 fl6; 214 215 memset(&fl6, 0, sizeof(fl6)); 216 217 fl6.flowi6_proto = sk->sk_protocol; 218 219 /* Fill in the dest address from the route entry passed with the skb 220 * and the source address from the transport. 221 */ 222 fl6.daddr = transport->ipaddr.v6.sin6_addr; 223 fl6.saddr = transport->saddr.v6.sin6_addr; 224 225 fl6.flowlabel = np->flow_label; 226 IP6_ECN_flow_xmit(sk, fl6.flowlabel); 227 if (ipv6_addr_type(&fl6.saddr) & IPV6_ADDR_LINKLOCAL) 228 fl6.flowi6_oif = transport->saddr.v6.sin6_scope_id; 229 else 230 fl6.flowi6_oif = sk->sk_bound_dev_if; 231 232 if (np->opt && np->opt->srcrt) { 233 struct rt0_hdr *rt0 = (struct rt0_hdr *) np->opt->srcrt; 234 fl6.daddr = *rt0->addr; 235 } 236 237 SCTP_DEBUG_PRINTK("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", 238 __func__, skb, skb->len, 239 &fl6.saddr, &fl6.daddr); 240 241 SCTP_INC_STATS(SCTP_MIB_OUTSCTPPACKS); 242 243 if (!(transport->param_flags & SPP_PMTUD_ENABLE)) 244 skb->local_df = 1; 245 246 return ip6_xmit(sk, skb, &fl6, np->opt, np->tclass); 247 } 248 249 /* Returns the dst cache entry for the given source and destination ip 250 * addresses. 251 */ 252 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr, 253 struct flowi *fl, struct sock *sk) 254 { 255 struct sctp_association *asoc = t->asoc; 256 struct dst_entry *dst = NULL; 257 struct flowi6 *fl6 = &fl->u.ip6; 258 struct sctp_bind_addr *bp; 259 struct sctp_sockaddr_entry *laddr; 260 union sctp_addr *baddr = NULL; 261 union sctp_addr *daddr = &t->ipaddr; 262 union sctp_addr dst_saddr; 263 __u8 matchlen = 0; 264 __u8 bmatchlen; 265 sctp_scope_t scope; 266 267 memset(fl6, 0, sizeof(struct flowi6)); 268 fl6->daddr = daddr->v6.sin6_addr; 269 fl6->fl6_dport = daddr->v6.sin6_port; 270 fl6->flowi6_proto = IPPROTO_SCTP; 271 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 272 fl6->flowi6_oif = daddr->v6.sin6_scope_id; 273 274 SCTP_DEBUG_PRINTK("%s: DST=%pI6 ", __func__, &fl6->daddr); 275 276 if (asoc) 277 fl6->fl6_sport = htons(asoc->base.bind_addr.port); 278 279 if (saddr) { 280 fl6->saddr = saddr->v6.sin6_addr; 281 fl6->fl6_sport = saddr->v6.sin6_port; 282 SCTP_DEBUG_PRINTK("SRC=%pI6 - ", &fl6->saddr); 283 } 284 285 dst = ip6_dst_lookup_flow(sk, fl6, NULL, false); 286 if (!asoc || saddr) 287 goto out; 288 289 bp = &asoc->base.bind_addr; 290 scope = sctp_scope(daddr); 291 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check 292 * to see if we can use it. 293 */ 294 if (!IS_ERR(dst)) { 295 /* Walk through the bind address list and look for a bind 296 * address that matches the source address of the returned dst. 297 */ 298 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port)); 299 rcu_read_lock(); 300 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 301 if (!laddr->valid || (laddr->state != SCTP_ADDR_SRC)) 302 continue; 303 304 /* Do not compare against v4 addrs */ 305 if ((laddr->a.sa.sa_family == AF_INET6) && 306 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) { 307 rcu_read_unlock(); 308 goto out; 309 } 310 } 311 rcu_read_unlock(); 312 /* None of the bound addresses match the source address of the 313 * dst. So release it. 314 */ 315 dst_release(dst); 316 dst = NULL; 317 } 318 319 /* Walk through the bind address list and try to get the 320 * best source address for a given destination. 321 */ 322 rcu_read_lock(); 323 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 324 if (!laddr->valid && laddr->state != SCTP_ADDR_SRC) 325 continue; 326 if ((laddr->a.sa.sa_family == AF_INET6) && 327 (scope <= sctp_scope(&laddr->a))) { 328 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a); 329 if (!baddr || (matchlen < bmatchlen)) { 330 baddr = &laddr->a; 331 matchlen = bmatchlen; 332 } 333 } 334 } 335 rcu_read_unlock(); 336 if (baddr) { 337 fl6->saddr = baddr->v6.sin6_addr; 338 fl6->fl6_sport = baddr->v6.sin6_port; 339 dst = ip6_dst_lookup_flow(sk, fl6, NULL, false); 340 } 341 342 out: 343 if (!IS_ERR(dst)) { 344 struct rt6_info *rt; 345 rt = (struct rt6_info *)dst; 346 t->dst = dst; 347 SCTP_DEBUG_PRINTK("rt6_dst:%pI6 rt6_src:%pI6\n", 348 &rt->rt6i_dst.addr, &fl6->saddr); 349 } else { 350 t->dst = NULL; 351 SCTP_DEBUG_PRINTK("NO ROUTE\n"); 352 } 353 } 354 355 /* Returns the number of consecutive initial bits that match in the 2 ipv6 356 * addresses. 357 */ 358 static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 359 union sctp_addr *s2) 360 { 361 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr); 362 } 363 364 /* Fills in the source address(saddr) based on the destination address(daddr) 365 * and asoc's bind address list. 366 */ 367 static void sctp_v6_get_saddr(struct sctp_sock *sk, 368 struct sctp_transport *t, 369 struct flowi *fl) 370 { 371 struct flowi6 *fl6 = &fl->u.ip6; 372 union sctp_addr *saddr = &t->saddr; 373 374 SCTP_DEBUG_PRINTK("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst); 375 376 if (t->dst) { 377 saddr->v6.sin6_family = AF_INET6; 378 saddr->v6.sin6_addr = fl6->saddr; 379 } 380 } 381 382 /* Make a copy of all potential local addresses. */ 383 static void sctp_v6_copy_addrlist(struct list_head *addrlist, 384 struct net_device *dev) 385 { 386 struct inet6_dev *in6_dev; 387 struct inet6_ifaddr *ifp; 388 struct sctp_sockaddr_entry *addr; 389 390 rcu_read_lock(); 391 if ((in6_dev = __in6_dev_get(dev)) == NULL) { 392 rcu_read_unlock(); 393 return; 394 } 395 396 read_lock_bh(&in6_dev->lock); 397 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) { 398 /* Add the address to the local list. */ 399 addr = t_new(struct sctp_sockaddr_entry, GFP_ATOMIC); 400 if (addr) { 401 addr->a.v6.sin6_family = AF_INET6; 402 addr->a.v6.sin6_port = 0; 403 addr->a.v6.sin6_addr = ifp->addr; 404 addr->a.v6.sin6_scope_id = dev->ifindex; 405 addr->valid = 1; 406 INIT_LIST_HEAD(&addr->list); 407 list_add_tail(&addr->list, addrlist); 408 } 409 } 410 411 read_unlock_bh(&in6_dev->lock); 412 rcu_read_unlock(); 413 } 414 415 /* Initialize a sockaddr_storage from in incoming skb. */ 416 static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb, 417 int is_saddr) 418 { 419 __be16 *port; 420 struct sctphdr *sh; 421 422 port = &addr->v6.sin6_port; 423 addr->v6.sin6_family = AF_INET6; 424 addr->v6.sin6_flowinfo = 0; /* FIXME */ 425 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif; 426 427 sh = sctp_hdr(skb); 428 if (is_saddr) { 429 *port = sh->source; 430 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 431 } else { 432 *port = sh->dest; 433 addr->v6.sin6_addr = ipv6_hdr(skb)->daddr; 434 } 435 } 436 437 /* Initialize an sctp_addr from a socket. */ 438 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk) 439 { 440 addr->v6.sin6_family = AF_INET6; 441 addr->v6.sin6_port = 0; 442 addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr; 443 } 444 445 /* Initialize sk->sk_rcv_saddr from sctp_addr. */ 446 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk) 447 { 448 if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) { 449 inet6_sk(sk)->rcv_saddr.s6_addr32[0] = 0; 450 inet6_sk(sk)->rcv_saddr.s6_addr32[1] = 0; 451 inet6_sk(sk)->rcv_saddr.s6_addr32[2] = htonl(0x0000ffff); 452 inet6_sk(sk)->rcv_saddr.s6_addr32[3] = 453 addr->v4.sin_addr.s_addr; 454 } else { 455 inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr; 456 } 457 } 458 459 /* Initialize sk->sk_daddr from sctp_addr. */ 460 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk) 461 { 462 if (addr->sa.sa_family == AF_INET && sctp_sk(sk)->v4mapped) { 463 inet6_sk(sk)->daddr.s6_addr32[0] = 0; 464 inet6_sk(sk)->daddr.s6_addr32[1] = 0; 465 inet6_sk(sk)->daddr.s6_addr32[2] = htonl(0x0000ffff); 466 inet6_sk(sk)->daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr; 467 } else { 468 inet6_sk(sk)->daddr = addr->v6.sin6_addr; 469 } 470 } 471 472 /* Initialize a sctp_addr from an address parameter. */ 473 static void sctp_v6_from_addr_param(union sctp_addr *addr, 474 union sctp_addr_param *param, 475 __be16 port, int iif) 476 { 477 addr->v6.sin6_family = AF_INET6; 478 addr->v6.sin6_port = port; 479 addr->v6.sin6_flowinfo = 0; /* BUG */ 480 addr->v6.sin6_addr = param->v6.addr; 481 addr->v6.sin6_scope_id = iif; 482 } 483 484 /* Initialize an address parameter from a sctp_addr and return the length 485 * of the address parameter. 486 */ 487 static int sctp_v6_to_addr_param(const union sctp_addr *addr, 488 union sctp_addr_param *param) 489 { 490 int length = sizeof(sctp_ipv6addr_param_t); 491 492 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS; 493 param->v6.param_hdr.length = htons(length); 494 param->v6.addr = addr->v6.sin6_addr; 495 496 return length; 497 } 498 499 /* Initialize a sctp_addr from struct in6_addr. */ 500 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 501 __be16 port) 502 { 503 addr->sa.sa_family = AF_INET6; 504 addr->v6.sin6_port = port; 505 addr->v6.sin6_addr = *saddr; 506 } 507 508 /* Compare addresses exactly. 509 * v4-mapped-v6 is also in consideration. 510 */ 511 static int sctp_v6_cmp_addr(const union sctp_addr *addr1, 512 const union sctp_addr *addr2) 513 { 514 if (addr1->sa.sa_family != addr2->sa.sa_family) { 515 if (addr1->sa.sa_family == AF_INET && 516 addr2->sa.sa_family == AF_INET6 && 517 ipv6_addr_v4mapped(&addr2->v6.sin6_addr)) { 518 if (addr2->v6.sin6_port == addr1->v4.sin_port && 519 addr2->v6.sin6_addr.s6_addr32[3] == 520 addr1->v4.sin_addr.s_addr) 521 return 1; 522 } 523 if (addr2->sa.sa_family == AF_INET && 524 addr1->sa.sa_family == AF_INET6 && 525 ipv6_addr_v4mapped(&addr1->v6.sin6_addr)) { 526 if (addr1->v6.sin6_port == addr2->v4.sin_port && 527 addr1->v6.sin6_addr.s6_addr32[3] == 528 addr2->v4.sin_addr.s_addr) 529 return 1; 530 } 531 return 0; 532 } 533 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr)) 534 return 0; 535 /* If this is a linklocal address, compare the scope_id. */ 536 if (ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) { 537 if (addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id && 538 (addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id)) { 539 return 0; 540 } 541 } 542 543 return 1; 544 } 545 546 /* Initialize addr struct to INADDR_ANY. */ 547 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port) 548 { 549 memset(addr, 0x00, sizeof(union sctp_addr)); 550 addr->v6.sin6_family = AF_INET6; 551 addr->v6.sin6_port = port; 552 } 553 554 /* Is this a wildcard address? */ 555 static int sctp_v6_is_any(const union sctp_addr *addr) 556 { 557 return ipv6_addr_any(&addr->v6.sin6_addr); 558 } 559 560 /* Should this be available for binding? */ 561 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp) 562 { 563 int type; 564 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr; 565 566 type = ipv6_addr_type(in6); 567 if (IPV6_ADDR_ANY == type) 568 return 1; 569 if (type == IPV6_ADDR_MAPPED) { 570 if (sp && !sp->v4mapped) 571 return 0; 572 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 573 return 0; 574 sctp_v6_map_v4(addr); 575 return sctp_get_af_specific(AF_INET)->available(addr, sp); 576 } 577 if (!(type & IPV6_ADDR_UNICAST)) 578 return 0; 579 580 return ipv6_chk_addr(&init_net, in6, NULL, 0); 581 } 582 583 /* This function checks if the address is a valid address to be used for 584 * SCTP. 585 * 586 * Output: 587 * Return 0 - If the address is a non-unicast or an illegal address. 588 * Return 1 - If the address is a unicast. 589 */ 590 static int sctp_v6_addr_valid(union sctp_addr *addr, 591 struct sctp_sock *sp, 592 const struct sk_buff *skb) 593 { 594 int ret = ipv6_addr_type(&addr->v6.sin6_addr); 595 596 /* Support v4-mapped-v6 address. */ 597 if (ret == IPV6_ADDR_MAPPED) { 598 /* Note: This routine is used in input, so v4-mapped-v6 599 * are disallowed here when there is no sctp_sock. 600 */ 601 if (!sp || !sp->v4mapped) 602 return 0; 603 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 604 return 0; 605 sctp_v6_map_v4(addr); 606 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb); 607 } 608 609 /* Is this a non-unicast address */ 610 if (!(ret & IPV6_ADDR_UNICAST)) 611 return 0; 612 613 return 1; 614 } 615 616 /* What is the scope of 'addr'? */ 617 static sctp_scope_t sctp_v6_scope(union sctp_addr *addr) 618 { 619 int v6scope; 620 sctp_scope_t retval; 621 622 /* The IPv6 scope is really a set of bit fields. 623 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope. 624 */ 625 626 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr); 627 switch (v6scope) { 628 case IFA_HOST: 629 retval = SCTP_SCOPE_LOOPBACK; 630 break; 631 case IFA_LINK: 632 retval = SCTP_SCOPE_LINK; 633 break; 634 case IFA_SITE: 635 retval = SCTP_SCOPE_PRIVATE; 636 break; 637 default: 638 retval = SCTP_SCOPE_GLOBAL; 639 break; 640 } 641 642 return retval; 643 } 644 645 /* Create and initialize a new sk for the socket to be returned by accept(). */ 646 static struct sock *sctp_v6_create_accept_sk(struct sock *sk, 647 struct sctp_association *asoc) 648 { 649 struct sock *newsk; 650 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 651 struct sctp6_sock *newsctp6sk; 652 653 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot); 654 if (!newsk) 655 goto out; 656 657 sock_init_data(NULL, newsk); 658 659 sctp_copy_sock(newsk, sk, asoc); 660 sock_reset_flag(sk, SOCK_ZAPPED); 661 662 newsctp6sk = (struct sctp6_sock *)newsk; 663 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6; 664 665 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped; 666 667 newnp = inet6_sk(newsk); 668 669 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 670 671 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() 672 * and getpeername(). 673 */ 674 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk); 675 676 sk_refcnt_debug_inc(newsk); 677 678 if (newsk->sk_prot->init(newsk)) { 679 sk_common_release(newsk); 680 newsk = NULL; 681 } 682 683 out: 684 return newsk; 685 } 686 687 /* Map v4 address to mapped v6 address */ 688 static void sctp_v6_addr_v4map(struct sctp_sock *sp, union sctp_addr *addr) 689 { 690 if (sp->v4mapped && AF_INET == addr->sa.sa_family) 691 sctp_v4_map_v6(addr); 692 } 693 694 /* Where did this skb come from? */ 695 static int sctp_v6_skb_iif(const struct sk_buff *skb) 696 { 697 struct inet6_skb_parm *opt = (struct inet6_skb_parm *) skb->cb; 698 return opt->iif; 699 } 700 701 /* Was this packet marked by Explicit Congestion Notification? */ 702 static int sctp_v6_is_ce(const struct sk_buff *skb) 703 { 704 return *((__u32 *)(ipv6_hdr(skb))) & htonl(1 << 20); 705 } 706 707 /* Dump the v6 addr to the seq file. */ 708 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr) 709 { 710 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr); 711 } 712 713 static void sctp_v6_ecn_capable(struct sock *sk) 714 { 715 inet6_sk(sk)->tclass |= INET_ECN_ECT_0; 716 } 717 718 /* Initialize a PF_INET6 socket msg_name. */ 719 static void sctp_inet6_msgname(char *msgname, int *addr_len) 720 { 721 struct sockaddr_in6 *sin6; 722 723 sin6 = (struct sockaddr_in6 *)msgname; 724 sin6->sin6_family = AF_INET6; 725 sin6->sin6_flowinfo = 0; 726 sin6->sin6_scope_id = 0; /*FIXME */ 727 *addr_len = sizeof(struct sockaddr_in6); 728 } 729 730 /* Initialize a PF_INET msgname from a ulpevent. */ 731 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event, 732 char *msgname, int *addrlen) 733 { 734 struct sockaddr_in6 *sin6, *sin6from; 735 736 if (msgname) { 737 union sctp_addr *addr; 738 struct sctp_association *asoc; 739 740 asoc = event->asoc; 741 sctp_inet6_msgname(msgname, addrlen); 742 sin6 = (struct sockaddr_in6 *)msgname; 743 sin6->sin6_port = htons(asoc->peer.port); 744 addr = &asoc->peer.primary_addr; 745 746 /* Note: If we go to a common v6 format, this code 747 * will change. 748 */ 749 750 /* Map ipv4 address into v4-mapped-on-v6 address. */ 751 if (sctp_sk(asoc->base.sk)->v4mapped && 752 AF_INET == addr->sa.sa_family) { 753 sctp_v4_map_v6((union sctp_addr *)sin6); 754 sin6->sin6_addr.s6_addr32[3] = 755 addr->v4.sin_addr.s_addr; 756 return; 757 } 758 759 sin6from = &asoc->peer.primary_addr.v6; 760 sin6->sin6_addr = sin6from->sin6_addr; 761 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) 762 sin6->sin6_scope_id = sin6from->sin6_scope_id; 763 } 764 } 765 766 /* Initialize a msg_name from an inbound skb. */ 767 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname, 768 int *addr_len) 769 { 770 struct sctphdr *sh; 771 struct sockaddr_in6 *sin6; 772 773 if (msgname) { 774 sctp_inet6_msgname(msgname, addr_len); 775 sin6 = (struct sockaddr_in6 *)msgname; 776 sh = sctp_hdr(skb); 777 sin6->sin6_port = sh->source; 778 779 /* Map ipv4 address into v4-mapped-on-v6 address. */ 780 if (sctp_sk(skb->sk)->v4mapped && 781 ip_hdr(skb)->version == 4) { 782 sctp_v4_map_v6((union sctp_addr *)sin6); 783 sin6->sin6_addr.s6_addr32[3] = ip_hdr(skb)->saddr; 784 return; 785 } 786 787 /* Otherwise, just copy the v6 address. */ 788 sin6->sin6_addr = ipv6_hdr(skb)->saddr; 789 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) { 790 struct sctp_ulpevent *ev = sctp_skb2event(skb); 791 sin6->sin6_scope_id = ev->iif; 792 } 793 } 794 } 795 796 /* Do we support this AF? */ 797 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp) 798 { 799 switch (family) { 800 case AF_INET6: 801 return 1; 802 /* v4-mapped-v6 addresses */ 803 case AF_INET: 804 if (!__ipv6_only_sock(sctp_opt2sk(sp))) 805 return 1; 806 default: 807 return 0; 808 } 809 } 810 811 /* Address matching with wildcards allowed. This extra level 812 * of indirection lets us choose whether a PF_INET6 should 813 * disallow any v4 addresses if we so choose. 814 */ 815 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, 816 const union sctp_addr *addr2, 817 struct sctp_sock *opt) 818 { 819 struct sctp_af *af1, *af2; 820 struct sock *sk = sctp_opt2sk(opt); 821 822 af1 = sctp_get_af_specific(addr1->sa.sa_family); 823 af2 = sctp_get_af_specific(addr2->sa.sa_family); 824 825 if (!af1 || !af2) 826 return 0; 827 828 /* If the socket is IPv6 only, v4 addrs will not match */ 829 if (__ipv6_only_sock(sk) && af1 != af2) 830 return 0; 831 832 /* Today, wildcard AF_INET/AF_INET6. */ 833 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2)) 834 return 1; 835 836 if (addr1->sa.sa_family != addr2->sa.sa_family) 837 return 0; 838 839 return af1->cmp_addr(addr1, addr2); 840 } 841 842 /* Verify that the provided sockaddr looks bindable. Common verification, 843 * has already been taken care of. 844 */ 845 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr) 846 { 847 struct sctp_af *af; 848 849 /* ASSERT: address family has already been verified. */ 850 if (addr->sa.sa_family != AF_INET6) 851 af = sctp_get_af_specific(addr->sa.sa_family); 852 else { 853 int type = ipv6_addr_type(&addr->v6.sin6_addr); 854 struct net_device *dev; 855 856 if (type & IPV6_ADDR_LINKLOCAL) { 857 if (!addr->v6.sin6_scope_id) 858 return 0; 859 rcu_read_lock(); 860 dev = dev_get_by_index_rcu(&init_net, 861 addr->v6.sin6_scope_id); 862 if (!dev || 863 !ipv6_chk_addr(&init_net, &addr->v6.sin6_addr, 864 dev, 0)) { 865 rcu_read_unlock(); 866 return 0; 867 } 868 rcu_read_unlock(); 869 } else if (type == IPV6_ADDR_MAPPED) { 870 if (!opt->v4mapped) 871 return 0; 872 } 873 874 af = opt->pf->af; 875 } 876 return af->available(addr, opt); 877 } 878 879 /* Verify that the provided sockaddr looks sendable. Common verification, 880 * has already been taken care of. 881 */ 882 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr) 883 { 884 struct sctp_af *af = NULL; 885 886 /* ASSERT: address family has already been verified. */ 887 if (addr->sa.sa_family != AF_INET6) 888 af = sctp_get_af_specific(addr->sa.sa_family); 889 else { 890 int type = ipv6_addr_type(&addr->v6.sin6_addr); 891 struct net_device *dev; 892 893 if (type & IPV6_ADDR_LINKLOCAL) { 894 if (!addr->v6.sin6_scope_id) 895 return 0; 896 rcu_read_lock(); 897 dev = dev_get_by_index_rcu(&init_net, 898 addr->v6.sin6_scope_id); 899 rcu_read_unlock(); 900 if (!dev) 901 return 0; 902 } 903 af = opt->pf->af; 904 } 905 906 return af != NULL; 907 } 908 909 /* Fill in Supported Address Type information for INIT and INIT-ACK 910 * chunks. Note: In the future, we may want to look at sock options 911 * to determine whether a PF_INET6 socket really wants to have IPV4 912 * addresses. 913 * Returns number of addresses supported. 914 */ 915 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt, 916 __be16 *types) 917 { 918 types[0] = SCTP_PARAM_IPV6_ADDRESS; 919 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) { 920 types[1] = SCTP_PARAM_IPV4_ADDRESS; 921 return 2; 922 } 923 return 1; 924 } 925 926 static const struct proto_ops inet6_seqpacket_ops = { 927 .family = PF_INET6, 928 .owner = THIS_MODULE, 929 .release = inet6_release, 930 .bind = inet6_bind, 931 .connect = inet_dgram_connect, 932 .socketpair = sock_no_socketpair, 933 .accept = inet_accept, 934 .getname = inet6_getname, 935 .poll = sctp_poll, 936 .ioctl = inet6_ioctl, 937 .listen = sctp_inet_listen, 938 .shutdown = inet_shutdown, 939 .setsockopt = sock_common_setsockopt, 940 .getsockopt = sock_common_getsockopt, 941 .sendmsg = inet_sendmsg, 942 .recvmsg = sock_common_recvmsg, 943 .mmap = sock_no_mmap, 944 #ifdef CONFIG_COMPAT 945 .compat_setsockopt = compat_sock_common_setsockopt, 946 .compat_getsockopt = compat_sock_common_getsockopt, 947 #endif 948 }; 949 950 static struct inet_protosw sctpv6_seqpacket_protosw = { 951 .type = SOCK_SEQPACKET, 952 .protocol = IPPROTO_SCTP, 953 .prot = &sctpv6_prot, 954 .ops = &inet6_seqpacket_ops, 955 .no_check = 0, 956 .flags = SCTP_PROTOSW_FLAG 957 }; 958 static struct inet_protosw sctpv6_stream_protosw = { 959 .type = SOCK_STREAM, 960 .protocol = IPPROTO_SCTP, 961 .prot = &sctpv6_prot, 962 .ops = &inet6_seqpacket_ops, 963 .no_check = 0, 964 .flags = SCTP_PROTOSW_FLAG, 965 }; 966 967 static int sctp6_rcv(struct sk_buff *skb) 968 { 969 return sctp_rcv(skb) ? -1 : 0; 970 } 971 972 static const struct inet6_protocol sctpv6_protocol = { 973 .handler = sctp6_rcv, 974 .err_handler = sctp_v6_err, 975 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, 976 }; 977 978 static struct sctp_af sctp_af_inet6 = { 979 .sa_family = AF_INET6, 980 .sctp_xmit = sctp_v6_xmit, 981 .setsockopt = ipv6_setsockopt, 982 .getsockopt = ipv6_getsockopt, 983 .get_dst = sctp_v6_get_dst, 984 .get_saddr = sctp_v6_get_saddr, 985 .copy_addrlist = sctp_v6_copy_addrlist, 986 .from_skb = sctp_v6_from_skb, 987 .from_sk = sctp_v6_from_sk, 988 .to_sk_saddr = sctp_v6_to_sk_saddr, 989 .to_sk_daddr = sctp_v6_to_sk_daddr, 990 .from_addr_param = sctp_v6_from_addr_param, 991 .to_addr_param = sctp_v6_to_addr_param, 992 .cmp_addr = sctp_v6_cmp_addr, 993 .scope = sctp_v6_scope, 994 .addr_valid = sctp_v6_addr_valid, 995 .inaddr_any = sctp_v6_inaddr_any, 996 .is_any = sctp_v6_is_any, 997 .available = sctp_v6_available, 998 .skb_iif = sctp_v6_skb_iif, 999 .is_ce = sctp_v6_is_ce, 1000 .seq_dump_addr = sctp_v6_seq_dump_addr, 1001 .ecn_capable = sctp_v6_ecn_capable, 1002 .net_header_len = sizeof(struct ipv6hdr), 1003 .sockaddr_len = sizeof(struct sockaddr_in6), 1004 #ifdef CONFIG_COMPAT 1005 .compat_setsockopt = compat_ipv6_setsockopt, 1006 .compat_getsockopt = compat_ipv6_getsockopt, 1007 #endif 1008 }; 1009 1010 static struct sctp_pf sctp_pf_inet6 = { 1011 .event_msgname = sctp_inet6_event_msgname, 1012 .skb_msgname = sctp_inet6_skb_msgname, 1013 .af_supported = sctp_inet6_af_supported, 1014 .cmp_addr = sctp_inet6_cmp_addr, 1015 .bind_verify = sctp_inet6_bind_verify, 1016 .send_verify = sctp_inet6_send_verify, 1017 .supported_addrs = sctp_inet6_supported_addrs, 1018 .create_accept_sk = sctp_v6_create_accept_sk, 1019 .addr_v4map = sctp_v6_addr_v4map, 1020 .af = &sctp_af_inet6, 1021 }; 1022 1023 /* Initialize IPv6 support and register with socket layer. */ 1024 void sctp_v6_pf_init(void) 1025 { 1026 /* Register the SCTP specific PF_INET6 functions. */ 1027 sctp_register_pf(&sctp_pf_inet6, PF_INET6); 1028 1029 /* Register the SCTP specific AF_INET6 functions. */ 1030 sctp_register_af(&sctp_af_inet6); 1031 } 1032 1033 void sctp_v6_pf_exit(void) 1034 { 1035 list_del(&sctp_af_inet6.list); 1036 } 1037 1038 /* Initialize IPv6 support and register with socket layer. */ 1039 int sctp_v6_protosw_init(void) 1040 { 1041 int rc; 1042 1043 rc = proto_register(&sctpv6_prot, 1); 1044 if (rc) 1045 return rc; 1046 1047 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */ 1048 inet6_register_protosw(&sctpv6_seqpacket_protosw); 1049 inet6_register_protosw(&sctpv6_stream_protosw); 1050 1051 return 0; 1052 } 1053 1054 void sctp_v6_protosw_exit(void) 1055 { 1056 inet6_unregister_protosw(&sctpv6_seqpacket_protosw); 1057 inet6_unregister_protosw(&sctpv6_stream_protosw); 1058 proto_unregister(&sctpv6_prot); 1059 } 1060 1061 1062 /* Register with inet6 layer. */ 1063 int sctp_v6_add_protocol(void) 1064 { 1065 /* Register notifier for inet6 address additions/deletions. */ 1066 register_inet6addr_notifier(&sctp_inet6addr_notifier); 1067 1068 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0) 1069 return -EAGAIN; 1070 1071 return 0; 1072 } 1073 1074 /* Unregister with inet6 layer. */ 1075 void sctp_v6_del_protocol(void) 1076 { 1077 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP); 1078 unregister_inet6addr_notifier(&sctp_inet6addr_notifier); 1079 } 1080