1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* SCTP kernel implementation 3 * (C) Copyright IBM Corp. 2002, 2004 4 * Copyright (c) 2001 Nokia, Inc. 5 * Copyright (c) 2001 La Monte H.P. Yarroll 6 * Copyright (c) 2002-2003 Intel Corp. 7 * 8 * This file is part of the SCTP kernel implementation 9 * 10 * SCTP over IPv6. 11 * 12 * Please send any bug reports or fixes you make to the 13 * email address(es): 14 * lksctp developers <linux-sctp@vger.kernel.org> 15 * 16 * Written or modified by: 17 * Le Yanqun <yanqun.le@nokia.com> 18 * Hui Huang <hui.huang@nokia.com> 19 * La Monte H.P. Yarroll <piggy@acm.org> 20 * Sridhar Samudrala <sri@us.ibm.com> 21 * Jon Grimm <jgrimm@us.ibm.com> 22 * Ardelle Fan <ardelle.fan@intel.com> 23 * 24 * Based on: 25 * linux/net/ipv6/tcp_ipv6.c 26 */ 27 28 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 29 30 #include <linux/module.h> 31 #include <linux/errno.h> 32 #include <linux/types.h> 33 #include <linux/socket.h> 34 #include <linux/sockios.h> 35 #include <linux/net.h> 36 #include <linux/in.h> 37 #include <linux/in6.h> 38 #include <linux/netdevice.h> 39 #include <linux/init.h> 40 #include <linux/ipsec.h> 41 #include <linux/slab.h> 42 43 #include <linux/ipv6.h> 44 #include <linux/icmpv6.h> 45 #include <linux/random.h> 46 #include <linux/seq_file.h> 47 48 #include <net/protocol.h> 49 #include <net/ndisc.h> 50 #include <net/ip.h> 51 #include <net/ipv6.h> 52 #include <net/transp_v6.h> 53 #include <net/addrconf.h> 54 #include <net/ip6_route.h> 55 #include <net/inet_common.h> 56 #include <net/inet_ecn.h> 57 #include <net/sctp/sctp.h> 58 59 #include <linux/uaccess.h> 60 61 static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 62 union sctp_addr *s2); 63 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 64 __be16 port); 65 static int sctp_v6_cmp_addr(const union sctp_addr *addr1, 66 const union sctp_addr *addr2); 67 68 /* Event handler for inet6 address addition/deletion events. 69 * The sctp_local_addr_list needs to be protocted by a spin lock since 70 * multiple notifiers (say IPv4 and IPv6) may be running at the same 71 * time and thus corrupt the list. 72 * The reader side is protected with RCU. 73 */ 74 static int sctp_inet6addr_event(struct notifier_block *this, unsigned long ev, 75 void *ptr) 76 { 77 struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr; 78 struct sctp_sockaddr_entry *addr = NULL; 79 struct sctp_sockaddr_entry *temp; 80 struct net *net = dev_net(ifa->idev->dev); 81 int found = 0; 82 83 switch (ev) { 84 case NETDEV_UP: 85 addr = kzalloc(sizeof(*addr), GFP_ATOMIC); 86 if (addr) { 87 addr->a.v6.sin6_family = AF_INET6; 88 addr->a.v6.sin6_addr = ifa->addr; 89 addr->a.v6.sin6_scope_id = ifa->idev->dev->ifindex; 90 addr->valid = 1; 91 spin_lock_bh(&net->sctp.local_addr_lock); 92 list_add_tail_rcu(&addr->list, &net->sctp.local_addr_list); 93 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_NEW); 94 spin_unlock_bh(&net->sctp.local_addr_lock); 95 } 96 break; 97 case NETDEV_DOWN: 98 spin_lock_bh(&net->sctp.local_addr_lock); 99 list_for_each_entry_safe(addr, temp, 100 &net->sctp.local_addr_list, list) { 101 if (addr->a.sa.sa_family == AF_INET6 && 102 ipv6_addr_equal(&addr->a.v6.sin6_addr, 103 &ifa->addr)) { 104 sctp_addr_wq_mgmt(net, addr, SCTP_ADDR_DEL); 105 found = 1; 106 addr->valid = 0; 107 list_del_rcu(&addr->list); 108 break; 109 } 110 } 111 spin_unlock_bh(&net->sctp.local_addr_lock); 112 if (found) 113 kfree_rcu(addr, rcu); 114 break; 115 } 116 117 return NOTIFY_DONE; 118 } 119 120 static struct notifier_block sctp_inet6addr_notifier = { 121 .notifier_call = sctp_inet6addr_event, 122 }; 123 124 /* ICMP error handler. */ 125 static int sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt, 126 u8 type, u8 code, int offset, __be32 info) 127 { 128 struct inet6_dev *idev; 129 struct sock *sk; 130 struct sctp_association *asoc; 131 struct sctp_transport *transport; 132 struct ipv6_pinfo *np; 133 __u16 saveip, savesctp; 134 int err, ret = 0; 135 struct net *net = dev_net(skb->dev); 136 137 idev = in6_dev_get(skb->dev); 138 139 /* Fix up skb to look at the embedded net header. */ 140 saveip = skb->network_header; 141 savesctp = skb->transport_header; 142 skb_reset_network_header(skb); 143 skb_set_transport_header(skb, offset); 144 sk = sctp_err_lookup(net, AF_INET6, skb, sctp_hdr(skb), &asoc, &transport); 145 /* Put back, the original pointers. */ 146 skb->network_header = saveip; 147 skb->transport_header = savesctp; 148 if (!sk) { 149 __ICMP6_INC_STATS(net, idev, ICMP6_MIB_INERRORS); 150 ret = -ENOENT; 151 goto out; 152 } 153 154 /* Warning: The sock lock is held. Remember to call 155 * sctp_err_finish! 156 */ 157 158 switch (type) { 159 case ICMPV6_PKT_TOOBIG: 160 if (ip6_sk_accept_pmtu(sk)) 161 sctp_icmp_frag_needed(sk, asoc, transport, ntohl(info)); 162 goto out_unlock; 163 case ICMPV6_PARAMPROB: 164 if (ICMPV6_UNK_NEXTHDR == code) { 165 sctp_icmp_proto_unreachable(sk, asoc, transport); 166 goto out_unlock; 167 } 168 break; 169 case NDISC_REDIRECT: 170 sctp_icmp_redirect(sk, transport, skb); 171 goto out_unlock; 172 default: 173 break; 174 } 175 176 np = inet6_sk(sk); 177 icmpv6_err_convert(type, code, &err); 178 if (!sock_owned_by_user(sk) && np->recverr) { 179 sk->sk_err = err; 180 sk->sk_error_report(sk); 181 } else { /* Only an error on timeout */ 182 sk->sk_err_soft = err; 183 } 184 185 out_unlock: 186 sctp_err_finish(sk, transport); 187 out: 188 if (likely(idev != NULL)) 189 in6_dev_put(idev); 190 191 return ret; 192 } 193 194 static int sctp_v6_xmit(struct sk_buff *skb, struct sctp_transport *transport) 195 { 196 struct sock *sk = skb->sk; 197 struct ipv6_pinfo *np = inet6_sk(sk); 198 struct flowi6 *fl6 = &transport->fl.u.ip6; 199 __u8 tclass = np->tclass; 200 int res; 201 202 pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb, 203 skb->len, &fl6->saddr, &fl6->daddr); 204 205 if (transport->dscp & SCTP_DSCP_SET_MASK) 206 tclass = transport->dscp & SCTP_DSCP_VAL_MASK; 207 208 if (INET_ECN_is_capable(tclass)) 209 IP6_ECN_flow_xmit(sk, fl6->flowlabel); 210 211 if (!(transport->param_flags & SPP_PMTUD_ENABLE)) 212 skb->ignore_df = 1; 213 214 SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS); 215 216 rcu_read_lock(); 217 res = ip6_xmit(sk, skb, fl6, sk->sk_mark, rcu_dereference(np->opt), 218 tclass); 219 rcu_read_unlock(); 220 return res; 221 } 222 223 /* Returns the dst cache entry for the given source and destination ip 224 * addresses. 225 */ 226 static void sctp_v6_get_dst(struct sctp_transport *t, union sctp_addr *saddr, 227 struct flowi *fl, struct sock *sk) 228 { 229 struct sctp_association *asoc = t->asoc; 230 struct dst_entry *dst = NULL; 231 struct flowi6 *fl6 = &fl->u.ip6; 232 struct sctp_bind_addr *bp; 233 struct ipv6_pinfo *np = inet6_sk(sk); 234 struct sctp_sockaddr_entry *laddr; 235 union sctp_addr *daddr = &t->ipaddr; 236 union sctp_addr dst_saddr; 237 struct in6_addr *final_p, final; 238 enum sctp_scope scope; 239 __u8 matchlen = 0; 240 241 memset(fl6, 0, sizeof(struct flowi6)); 242 fl6->daddr = daddr->v6.sin6_addr; 243 fl6->fl6_dport = daddr->v6.sin6_port; 244 fl6->flowi6_proto = IPPROTO_SCTP; 245 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 246 fl6->flowi6_oif = daddr->v6.sin6_scope_id; 247 else if (asoc) 248 fl6->flowi6_oif = asoc->base.sk->sk_bound_dev_if; 249 if (t->flowlabel & SCTP_FLOWLABEL_SET_MASK) 250 fl6->flowlabel = htonl(t->flowlabel & SCTP_FLOWLABEL_VAL_MASK); 251 252 if (np->sndflow && (fl6->flowlabel & IPV6_FLOWLABEL_MASK)) { 253 struct ip6_flowlabel *flowlabel; 254 255 flowlabel = fl6_sock_lookup(sk, fl6->flowlabel); 256 if (IS_ERR(flowlabel)) 257 goto out; 258 fl6_sock_release(flowlabel); 259 } 260 261 pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr); 262 263 if (asoc) 264 fl6->fl6_sport = htons(asoc->base.bind_addr.port); 265 266 if (saddr) { 267 fl6->saddr = saddr->v6.sin6_addr; 268 if (!fl6->fl6_sport) 269 fl6->fl6_sport = saddr->v6.sin6_port; 270 271 pr_debug("src=%pI6 - ", &fl6->saddr); 272 } 273 274 rcu_read_lock(); 275 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 276 rcu_read_unlock(); 277 278 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 279 if (!asoc || saddr) 280 goto out; 281 282 bp = &asoc->base.bind_addr; 283 scope = sctp_scope(daddr); 284 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check 285 * to see if we can use it. 286 */ 287 if (!IS_ERR(dst)) { 288 /* Walk through the bind address list and look for a bind 289 * address that matches the source address of the returned dst. 290 */ 291 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port)); 292 rcu_read_lock(); 293 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 294 if (!laddr->valid || laddr->state == SCTP_ADDR_DEL || 295 (laddr->state != SCTP_ADDR_SRC && 296 !asoc->src_out_of_asoc_ok)) 297 continue; 298 299 /* Do not compare against v4 addrs */ 300 if ((laddr->a.sa.sa_family == AF_INET6) && 301 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) { 302 rcu_read_unlock(); 303 goto out; 304 } 305 } 306 rcu_read_unlock(); 307 /* None of the bound addresses match the source address of the 308 * dst. So release it. 309 */ 310 dst_release(dst); 311 dst = NULL; 312 } 313 314 /* Walk through the bind address list and try to get the 315 * best source address for a given destination. 316 */ 317 rcu_read_lock(); 318 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 319 struct dst_entry *bdst; 320 __u8 bmatchlen; 321 322 if (!laddr->valid || 323 laddr->state != SCTP_ADDR_SRC || 324 laddr->a.sa.sa_family != AF_INET6 || 325 scope > sctp_scope(&laddr->a)) 326 continue; 327 328 fl6->saddr = laddr->a.v6.sin6_addr; 329 fl6->fl6_sport = laddr->a.v6.sin6_port; 330 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 331 bdst = ip6_dst_lookup_flow(sk, fl6, final_p); 332 333 if (IS_ERR(bdst)) 334 continue; 335 336 if (ipv6_chk_addr(dev_net(bdst->dev), 337 &laddr->a.v6.sin6_addr, bdst->dev, 1)) { 338 if (!IS_ERR_OR_NULL(dst)) 339 dst_release(dst); 340 dst = bdst; 341 break; 342 } 343 344 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a); 345 if (matchlen > bmatchlen) { 346 dst_release(bdst); 347 continue; 348 } 349 350 if (!IS_ERR_OR_NULL(dst)) 351 dst_release(dst); 352 dst = bdst; 353 matchlen = bmatchlen; 354 } 355 rcu_read_unlock(); 356 357 out: 358 if (!IS_ERR_OR_NULL(dst)) { 359 struct rt6_info *rt; 360 361 rt = (struct rt6_info *)dst; 362 t->dst = dst; 363 t->dst_cookie = rt6_get_cookie(rt); 364 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n", 365 &rt->rt6i_dst.addr, rt->rt6i_dst.plen, 366 &fl6->saddr); 367 } else { 368 t->dst = NULL; 369 370 pr_debug("no route\n"); 371 } 372 } 373 374 /* Returns the number of consecutive initial bits that match in the 2 ipv6 375 * addresses. 376 */ 377 static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 378 union sctp_addr *s2) 379 { 380 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr); 381 } 382 383 /* Fills in the source address(saddr) based on the destination address(daddr) 384 * and asoc's bind address list. 385 */ 386 static void sctp_v6_get_saddr(struct sctp_sock *sk, 387 struct sctp_transport *t, 388 struct flowi *fl) 389 { 390 struct flowi6 *fl6 = &fl->u.ip6; 391 union sctp_addr *saddr = &t->saddr; 392 393 pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst); 394 395 if (t->dst) { 396 saddr->v6.sin6_family = AF_INET6; 397 saddr->v6.sin6_addr = fl6->saddr; 398 } 399 } 400 401 /* Make a copy of all potential local addresses. */ 402 static void sctp_v6_copy_addrlist(struct list_head *addrlist, 403 struct net_device *dev) 404 { 405 struct inet6_dev *in6_dev; 406 struct inet6_ifaddr *ifp; 407 struct sctp_sockaddr_entry *addr; 408 409 rcu_read_lock(); 410 if ((in6_dev = __in6_dev_get(dev)) == NULL) { 411 rcu_read_unlock(); 412 return; 413 } 414 415 read_lock_bh(&in6_dev->lock); 416 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) { 417 /* Add the address to the local list. */ 418 addr = kzalloc(sizeof(*addr), GFP_ATOMIC); 419 if (addr) { 420 addr->a.v6.sin6_family = AF_INET6; 421 addr->a.v6.sin6_addr = ifp->addr; 422 addr->a.v6.sin6_scope_id = dev->ifindex; 423 addr->valid = 1; 424 INIT_LIST_HEAD(&addr->list); 425 list_add_tail(&addr->list, addrlist); 426 } 427 } 428 429 read_unlock_bh(&in6_dev->lock); 430 rcu_read_unlock(); 431 } 432 433 /* Copy over any ip options */ 434 static void sctp_v6_copy_ip_options(struct sock *sk, struct sock *newsk) 435 { 436 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 437 struct ipv6_txoptions *opt; 438 439 newnp = inet6_sk(newsk); 440 441 rcu_read_lock(); 442 opt = rcu_dereference(np->opt); 443 if (opt) { 444 opt = ipv6_dup_options(newsk, opt); 445 if (!opt) 446 pr_err("%s: Failed to copy ip options\n", __func__); 447 } 448 RCU_INIT_POINTER(newnp->opt, opt); 449 rcu_read_unlock(); 450 } 451 452 /* Account for the IP options */ 453 static int sctp_v6_ip_options_len(struct sock *sk) 454 { 455 struct ipv6_pinfo *np = inet6_sk(sk); 456 struct ipv6_txoptions *opt; 457 int len = 0; 458 459 rcu_read_lock(); 460 opt = rcu_dereference(np->opt); 461 if (opt) 462 len = opt->opt_flen + opt->opt_nflen; 463 464 rcu_read_unlock(); 465 return len; 466 } 467 468 /* Initialize a sockaddr_storage from in incoming skb. */ 469 static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb, 470 int is_saddr) 471 { 472 /* Always called on head skb, so this is safe */ 473 struct sctphdr *sh = sctp_hdr(skb); 474 struct sockaddr_in6 *sa = &addr->v6; 475 476 addr->v6.sin6_family = AF_INET6; 477 addr->v6.sin6_flowinfo = 0; /* FIXME */ 478 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif; 479 480 if (is_saddr) { 481 sa->sin6_port = sh->source; 482 sa->sin6_addr = ipv6_hdr(skb)->saddr; 483 } else { 484 sa->sin6_port = sh->dest; 485 sa->sin6_addr = ipv6_hdr(skb)->daddr; 486 } 487 } 488 489 /* Initialize an sctp_addr from a socket. */ 490 static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk) 491 { 492 addr->v6.sin6_family = AF_INET6; 493 addr->v6.sin6_port = 0; 494 addr->v6.sin6_addr = sk->sk_v6_rcv_saddr; 495 } 496 497 /* Initialize sk->sk_rcv_saddr from sctp_addr. */ 498 static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk) 499 { 500 if (addr->sa.sa_family == AF_INET) { 501 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0; 502 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0; 503 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff); 504 sk->sk_v6_rcv_saddr.s6_addr32[3] = 505 addr->v4.sin_addr.s_addr; 506 } else { 507 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr; 508 } 509 } 510 511 /* Initialize sk->sk_daddr from sctp_addr. */ 512 static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk) 513 { 514 if (addr->sa.sa_family == AF_INET) { 515 sk->sk_v6_daddr.s6_addr32[0] = 0; 516 sk->sk_v6_daddr.s6_addr32[1] = 0; 517 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff); 518 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr; 519 } else { 520 sk->sk_v6_daddr = addr->v6.sin6_addr; 521 } 522 } 523 524 /* Initialize a sctp_addr from an address parameter. */ 525 static void sctp_v6_from_addr_param(union sctp_addr *addr, 526 union sctp_addr_param *param, 527 __be16 port, int iif) 528 { 529 addr->v6.sin6_family = AF_INET6; 530 addr->v6.sin6_port = port; 531 addr->v6.sin6_flowinfo = 0; /* BUG */ 532 addr->v6.sin6_addr = param->v6.addr; 533 addr->v6.sin6_scope_id = iif; 534 } 535 536 /* Initialize an address parameter from a sctp_addr and return the length 537 * of the address parameter. 538 */ 539 static int sctp_v6_to_addr_param(const union sctp_addr *addr, 540 union sctp_addr_param *param) 541 { 542 int length = sizeof(struct sctp_ipv6addr_param); 543 544 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS; 545 param->v6.param_hdr.length = htons(length); 546 param->v6.addr = addr->v6.sin6_addr; 547 548 return length; 549 } 550 551 /* Initialize a sctp_addr from struct in6_addr. */ 552 static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 553 __be16 port) 554 { 555 addr->sa.sa_family = AF_INET6; 556 addr->v6.sin6_port = port; 557 addr->v6.sin6_flowinfo = 0; 558 addr->v6.sin6_addr = *saddr; 559 addr->v6.sin6_scope_id = 0; 560 } 561 562 static int __sctp_v6_cmp_addr(const union sctp_addr *addr1, 563 const union sctp_addr *addr2) 564 { 565 if (addr1->sa.sa_family != addr2->sa.sa_family) { 566 if (addr1->sa.sa_family == AF_INET && 567 addr2->sa.sa_family == AF_INET6 && 568 ipv6_addr_v4mapped(&addr2->v6.sin6_addr) && 569 addr2->v6.sin6_addr.s6_addr32[3] == 570 addr1->v4.sin_addr.s_addr) 571 return 1; 572 573 if (addr2->sa.sa_family == AF_INET && 574 addr1->sa.sa_family == AF_INET6 && 575 ipv6_addr_v4mapped(&addr1->v6.sin6_addr) && 576 addr1->v6.sin6_addr.s6_addr32[3] == 577 addr2->v4.sin_addr.s_addr) 578 return 1; 579 580 return 0; 581 } 582 583 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr)) 584 return 0; 585 586 /* If this is a linklocal address, compare the scope_id. */ 587 if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) && 588 addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id && 589 addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id) 590 return 0; 591 592 return 1; 593 } 594 595 /* Compare addresses exactly. 596 * v4-mapped-v6 is also in consideration. 597 */ 598 static int sctp_v6_cmp_addr(const union sctp_addr *addr1, 599 const union sctp_addr *addr2) 600 { 601 return __sctp_v6_cmp_addr(addr1, addr2) && 602 addr1->v6.sin6_port == addr2->v6.sin6_port; 603 } 604 605 /* Initialize addr struct to INADDR_ANY. */ 606 static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port) 607 { 608 memset(addr, 0x00, sizeof(union sctp_addr)); 609 addr->v6.sin6_family = AF_INET6; 610 addr->v6.sin6_port = port; 611 } 612 613 /* Is this a wildcard address? */ 614 static int sctp_v6_is_any(const union sctp_addr *addr) 615 { 616 return ipv6_addr_any(&addr->v6.sin6_addr); 617 } 618 619 /* Should this be available for binding? */ 620 static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp) 621 { 622 int type; 623 struct net *net = sock_net(&sp->inet.sk); 624 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr; 625 626 type = ipv6_addr_type(in6); 627 if (IPV6_ADDR_ANY == type) 628 return 1; 629 if (type == IPV6_ADDR_MAPPED) { 630 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 631 return 0; 632 sctp_v6_map_v4(addr); 633 return sctp_get_af_specific(AF_INET)->available(addr, sp); 634 } 635 if (!(type & IPV6_ADDR_UNICAST)) 636 return 0; 637 638 return sp->inet.freebind || net->ipv6.sysctl.ip_nonlocal_bind || 639 ipv6_chk_addr(net, in6, NULL, 0); 640 } 641 642 /* This function checks if the address is a valid address to be used for 643 * SCTP. 644 * 645 * Output: 646 * Return 0 - If the address is a non-unicast or an illegal address. 647 * Return 1 - If the address is a unicast. 648 */ 649 static int sctp_v6_addr_valid(union sctp_addr *addr, 650 struct sctp_sock *sp, 651 const struct sk_buff *skb) 652 { 653 int ret = ipv6_addr_type(&addr->v6.sin6_addr); 654 655 /* Support v4-mapped-v6 address. */ 656 if (ret == IPV6_ADDR_MAPPED) { 657 /* Note: This routine is used in input, so v4-mapped-v6 658 * are disallowed here when there is no sctp_sock. 659 */ 660 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 661 return 0; 662 sctp_v6_map_v4(addr); 663 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb); 664 } 665 666 /* Is this a non-unicast address */ 667 if (!(ret & IPV6_ADDR_UNICAST)) 668 return 0; 669 670 return 1; 671 } 672 673 /* What is the scope of 'addr'? */ 674 static enum sctp_scope sctp_v6_scope(union sctp_addr *addr) 675 { 676 enum sctp_scope retval; 677 int v6scope; 678 679 /* The IPv6 scope is really a set of bit fields. 680 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope. 681 */ 682 683 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr); 684 switch (v6scope) { 685 case IFA_HOST: 686 retval = SCTP_SCOPE_LOOPBACK; 687 break; 688 case IFA_LINK: 689 retval = SCTP_SCOPE_LINK; 690 break; 691 case IFA_SITE: 692 retval = SCTP_SCOPE_PRIVATE; 693 break; 694 default: 695 retval = SCTP_SCOPE_GLOBAL; 696 break; 697 } 698 699 return retval; 700 } 701 702 /* Create and initialize a new sk for the socket to be returned by accept(). */ 703 static struct sock *sctp_v6_create_accept_sk(struct sock *sk, 704 struct sctp_association *asoc, 705 bool kern) 706 { 707 struct sock *newsk; 708 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 709 struct sctp6_sock *newsctp6sk; 710 711 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern); 712 if (!newsk) 713 goto out; 714 715 sock_init_data(NULL, newsk); 716 717 sctp_copy_sock(newsk, sk, asoc); 718 sock_reset_flag(sk, SOCK_ZAPPED); 719 720 newsctp6sk = (struct sctp6_sock *)newsk; 721 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6; 722 723 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped; 724 725 newnp = inet6_sk(newsk); 726 727 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 728 newnp->ipv6_mc_list = NULL; 729 newnp->ipv6_ac_list = NULL; 730 newnp->ipv6_fl_list = NULL; 731 732 sctp_v6_copy_ip_options(sk, newsk); 733 734 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() 735 * and getpeername(). 736 */ 737 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk); 738 739 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr; 740 741 sk_refcnt_debug_inc(newsk); 742 743 if (newsk->sk_prot->init(newsk)) { 744 sk_common_release(newsk); 745 newsk = NULL; 746 } 747 748 out: 749 return newsk; 750 } 751 752 /* Format a sockaddr for return to user space. This makes sure the return is 753 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. 754 */ 755 static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr) 756 { 757 if (sp->v4mapped) { 758 if (addr->sa.sa_family == AF_INET) 759 sctp_v4_map_v6(addr); 760 } else { 761 if (addr->sa.sa_family == AF_INET6 && 762 ipv6_addr_v4mapped(&addr->v6.sin6_addr)) 763 sctp_v6_map_v4(addr); 764 } 765 766 if (addr->sa.sa_family == AF_INET) { 767 memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero)); 768 return sizeof(struct sockaddr_in); 769 } 770 return sizeof(struct sockaddr_in6); 771 } 772 773 /* Where did this skb come from? */ 774 static int sctp_v6_skb_iif(const struct sk_buff *skb) 775 { 776 return IP6CB(skb)->iif; 777 } 778 779 /* Was this packet marked by Explicit Congestion Notification? */ 780 static int sctp_v6_is_ce(const struct sk_buff *skb) 781 { 782 return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20); 783 } 784 785 /* Dump the v6 addr to the seq file. */ 786 static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr) 787 { 788 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr); 789 } 790 791 static void sctp_v6_ecn_capable(struct sock *sk) 792 { 793 inet6_sk(sk)->tclass |= INET_ECN_ECT_0; 794 } 795 796 /* Initialize a PF_INET msgname from a ulpevent. */ 797 static void sctp_inet6_event_msgname(struct sctp_ulpevent *event, 798 char *msgname, int *addrlen) 799 { 800 union sctp_addr *addr; 801 struct sctp_association *asoc; 802 union sctp_addr *paddr; 803 804 if (!msgname) 805 return; 806 807 addr = (union sctp_addr *)msgname; 808 asoc = event->asoc; 809 paddr = &asoc->peer.primary_addr; 810 811 if (paddr->sa.sa_family == AF_INET) { 812 addr->v4.sin_family = AF_INET; 813 addr->v4.sin_port = htons(asoc->peer.port); 814 addr->v4.sin_addr = paddr->v4.sin_addr; 815 } else { 816 addr->v6.sin6_family = AF_INET6; 817 addr->v6.sin6_flowinfo = 0; 818 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 819 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id; 820 else 821 addr->v6.sin6_scope_id = 0; 822 addr->v6.sin6_port = htons(asoc->peer.port); 823 addr->v6.sin6_addr = paddr->v6.sin6_addr; 824 } 825 826 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr); 827 } 828 829 /* Initialize a msg_name from an inbound skb. */ 830 static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname, 831 int *addr_len) 832 { 833 union sctp_addr *addr; 834 struct sctphdr *sh; 835 836 if (!msgname) 837 return; 838 839 addr = (union sctp_addr *)msgname; 840 sh = sctp_hdr(skb); 841 842 if (ip_hdr(skb)->version == 4) { 843 addr->v4.sin_family = AF_INET; 844 addr->v4.sin_port = sh->source; 845 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr; 846 } else { 847 addr->v6.sin6_family = AF_INET6; 848 addr->v6.sin6_flowinfo = 0; 849 addr->v6.sin6_port = sh->source; 850 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 851 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 852 addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb); 853 else 854 addr->v6.sin6_scope_id = 0; 855 } 856 857 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr); 858 } 859 860 /* Do we support this AF? */ 861 static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp) 862 { 863 switch (family) { 864 case AF_INET6: 865 return 1; 866 /* v4-mapped-v6 addresses */ 867 case AF_INET: 868 if (!__ipv6_only_sock(sctp_opt2sk(sp))) 869 return 1; 870 /* fallthru */ 871 default: 872 return 0; 873 } 874 } 875 876 /* Address matching with wildcards allowed. This extra level 877 * of indirection lets us choose whether a PF_INET6 should 878 * disallow any v4 addresses if we so choose. 879 */ 880 static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, 881 const union sctp_addr *addr2, 882 struct sctp_sock *opt) 883 { 884 struct sock *sk = sctp_opt2sk(opt); 885 struct sctp_af *af1, *af2; 886 887 af1 = sctp_get_af_specific(addr1->sa.sa_family); 888 af2 = sctp_get_af_specific(addr2->sa.sa_family); 889 890 if (!af1 || !af2) 891 return 0; 892 893 /* If the socket is IPv6 only, v4 addrs will not match */ 894 if (__ipv6_only_sock(sk) && af1 != af2) 895 return 0; 896 897 /* Today, wildcard AF_INET/AF_INET6. */ 898 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2)) 899 return 1; 900 901 if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET) 902 return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr; 903 904 return __sctp_v6_cmp_addr(addr1, addr2); 905 } 906 907 /* Verify that the provided sockaddr looks bindable. Common verification, 908 * has already been taken care of. 909 */ 910 static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr) 911 { 912 struct sctp_af *af; 913 914 /* ASSERT: address family has already been verified. */ 915 if (addr->sa.sa_family != AF_INET6) 916 af = sctp_get_af_specific(addr->sa.sa_family); 917 else { 918 int type = ipv6_addr_type(&addr->v6.sin6_addr); 919 struct net_device *dev; 920 921 if (type & IPV6_ADDR_LINKLOCAL) { 922 struct net *net; 923 if (!addr->v6.sin6_scope_id) 924 return 0; 925 net = sock_net(&opt->inet.sk); 926 rcu_read_lock(); 927 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id); 928 if (!dev || !(opt->inet.freebind || 929 net->ipv6.sysctl.ip_nonlocal_bind || 930 ipv6_chk_addr(net, &addr->v6.sin6_addr, 931 dev, 0))) { 932 rcu_read_unlock(); 933 return 0; 934 } 935 rcu_read_unlock(); 936 } 937 938 af = opt->pf->af; 939 } 940 return af->available(addr, opt); 941 } 942 943 /* Verify that the provided sockaddr looks sendable. Common verification, 944 * has already been taken care of. 945 */ 946 static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr) 947 { 948 struct sctp_af *af = NULL; 949 950 /* ASSERT: address family has already been verified. */ 951 if (addr->sa.sa_family != AF_INET6) 952 af = sctp_get_af_specific(addr->sa.sa_family); 953 else { 954 int type = ipv6_addr_type(&addr->v6.sin6_addr); 955 struct net_device *dev; 956 957 if (type & IPV6_ADDR_LINKLOCAL) { 958 if (!addr->v6.sin6_scope_id) 959 return 0; 960 rcu_read_lock(); 961 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk), 962 addr->v6.sin6_scope_id); 963 rcu_read_unlock(); 964 if (!dev) 965 return 0; 966 } 967 af = opt->pf->af; 968 } 969 970 return af != NULL; 971 } 972 973 /* Fill in Supported Address Type information for INIT and INIT-ACK 974 * chunks. Note: In the future, we may want to look at sock options 975 * to determine whether a PF_INET6 socket really wants to have IPV4 976 * addresses. 977 * Returns number of addresses supported. 978 */ 979 static int sctp_inet6_supported_addrs(const struct sctp_sock *opt, 980 __be16 *types) 981 { 982 types[0] = SCTP_PARAM_IPV6_ADDRESS; 983 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) { 984 types[1] = SCTP_PARAM_IPV4_ADDRESS; 985 return 2; 986 } 987 return 1; 988 } 989 990 /* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */ 991 static int sctp_getname(struct socket *sock, struct sockaddr *uaddr, 992 int peer) 993 { 994 int rc; 995 996 rc = inet6_getname(sock, uaddr, peer); 997 998 if (rc < 0) 999 return rc; 1000 1001 rc = sctp_v6_addr_to_user(sctp_sk(sock->sk), 1002 (union sctp_addr *)uaddr); 1003 1004 return rc; 1005 } 1006 1007 static const struct proto_ops inet6_seqpacket_ops = { 1008 .family = PF_INET6, 1009 .owner = THIS_MODULE, 1010 .release = inet6_release, 1011 .bind = inet6_bind, 1012 .connect = sctp_inet_connect, 1013 .socketpair = sock_no_socketpair, 1014 .accept = inet_accept, 1015 .getname = sctp_getname, 1016 .poll = sctp_poll, 1017 .ioctl = inet6_ioctl, 1018 .gettstamp = sock_gettstamp, 1019 .listen = sctp_inet_listen, 1020 .shutdown = inet_shutdown, 1021 .setsockopt = sock_common_setsockopt, 1022 .getsockopt = sock_common_getsockopt, 1023 .sendmsg = inet_sendmsg, 1024 .recvmsg = inet_recvmsg, 1025 .mmap = sock_no_mmap, 1026 #ifdef CONFIG_COMPAT 1027 .compat_setsockopt = compat_sock_common_setsockopt, 1028 .compat_getsockopt = compat_sock_common_getsockopt, 1029 #endif 1030 }; 1031 1032 static struct inet_protosw sctpv6_seqpacket_protosw = { 1033 .type = SOCK_SEQPACKET, 1034 .protocol = IPPROTO_SCTP, 1035 .prot = &sctpv6_prot, 1036 .ops = &inet6_seqpacket_ops, 1037 .flags = SCTP_PROTOSW_FLAG 1038 }; 1039 static struct inet_protosw sctpv6_stream_protosw = { 1040 .type = SOCK_STREAM, 1041 .protocol = IPPROTO_SCTP, 1042 .prot = &sctpv6_prot, 1043 .ops = &inet6_seqpacket_ops, 1044 .flags = SCTP_PROTOSW_FLAG, 1045 }; 1046 1047 static int sctp6_rcv(struct sk_buff *skb) 1048 { 1049 return sctp_rcv(skb) ? -1 : 0; 1050 } 1051 1052 static const struct inet6_protocol sctpv6_protocol = { 1053 .handler = sctp6_rcv, 1054 .err_handler = sctp_v6_err, 1055 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, 1056 }; 1057 1058 static struct sctp_af sctp_af_inet6 = { 1059 .sa_family = AF_INET6, 1060 .sctp_xmit = sctp_v6_xmit, 1061 .setsockopt = ipv6_setsockopt, 1062 .getsockopt = ipv6_getsockopt, 1063 .get_dst = sctp_v6_get_dst, 1064 .get_saddr = sctp_v6_get_saddr, 1065 .copy_addrlist = sctp_v6_copy_addrlist, 1066 .from_skb = sctp_v6_from_skb, 1067 .from_sk = sctp_v6_from_sk, 1068 .from_addr_param = sctp_v6_from_addr_param, 1069 .to_addr_param = sctp_v6_to_addr_param, 1070 .cmp_addr = sctp_v6_cmp_addr, 1071 .scope = sctp_v6_scope, 1072 .addr_valid = sctp_v6_addr_valid, 1073 .inaddr_any = sctp_v6_inaddr_any, 1074 .is_any = sctp_v6_is_any, 1075 .available = sctp_v6_available, 1076 .skb_iif = sctp_v6_skb_iif, 1077 .is_ce = sctp_v6_is_ce, 1078 .seq_dump_addr = sctp_v6_seq_dump_addr, 1079 .ecn_capable = sctp_v6_ecn_capable, 1080 .net_header_len = sizeof(struct ipv6hdr), 1081 .sockaddr_len = sizeof(struct sockaddr_in6), 1082 .ip_options_len = sctp_v6_ip_options_len, 1083 #ifdef CONFIG_COMPAT 1084 .compat_setsockopt = compat_ipv6_setsockopt, 1085 .compat_getsockopt = compat_ipv6_getsockopt, 1086 #endif 1087 }; 1088 1089 static struct sctp_pf sctp_pf_inet6 = { 1090 .event_msgname = sctp_inet6_event_msgname, 1091 .skb_msgname = sctp_inet6_skb_msgname, 1092 .af_supported = sctp_inet6_af_supported, 1093 .cmp_addr = sctp_inet6_cmp_addr, 1094 .bind_verify = sctp_inet6_bind_verify, 1095 .send_verify = sctp_inet6_send_verify, 1096 .supported_addrs = sctp_inet6_supported_addrs, 1097 .create_accept_sk = sctp_v6_create_accept_sk, 1098 .addr_to_user = sctp_v6_addr_to_user, 1099 .to_sk_saddr = sctp_v6_to_sk_saddr, 1100 .to_sk_daddr = sctp_v6_to_sk_daddr, 1101 .copy_ip_options = sctp_v6_copy_ip_options, 1102 .af = &sctp_af_inet6, 1103 }; 1104 1105 /* Initialize IPv6 support and register with socket layer. */ 1106 void sctp_v6_pf_init(void) 1107 { 1108 /* Register the SCTP specific PF_INET6 functions. */ 1109 sctp_register_pf(&sctp_pf_inet6, PF_INET6); 1110 1111 /* Register the SCTP specific AF_INET6 functions. */ 1112 sctp_register_af(&sctp_af_inet6); 1113 } 1114 1115 void sctp_v6_pf_exit(void) 1116 { 1117 list_del(&sctp_af_inet6.list); 1118 } 1119 1120 /* Initialize IPv6 support and register with socket layer. */ 1121 int sctp_v6_protosw_init(void) 1122 { 1123 int rc; 1124 1125 rc = proto_register(&sctpv6_prot, 1); 1126 if (rc) 1127 return rc; 1128 1129 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */ 1130 inet6_register_protosw(&sctpv6_seqpacket_protosw); 1131 inet6_register_protosw(&sctpv6_stream_protosw); 1132 1133 return 0; 1134 } 1135 1136 void sctp_v6_protosw_exit(void) 1137 { 1138 inet6_unregister_protosw(&sctpv6_seqpacket_protosw); 1139 inet6_unregister_protosw(&sctpv6_stream_protosw); 1140 proto_unregister(&sctpv6_prot); 1141 } 1142 1143 1144 /* Register with inet6 layer. */ 1145 int sctp_v6_add_protocol(void) 1146 { 1147 /* Register notifier for inet6 address additions/deletions. */ 1148 register_inet6addr_notifier(&sctp_inet6addr_notifier); 1149 1150 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0) 1151 return -EAGAIN; 1152 1153 return 0; 1154 } 1155 1156 /* Unregister with inet6 layer. */ 1157 void sctp_v6_del_protocol(void) 1158 { 1159 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP); 1160 unregister_inet6addr_notifier(&sctp_inet6addr_notifier); 1161 } 1162