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 61static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 62 union sctp_addr *s2); 63static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 64 __be16 port); 65static 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 */ 74static 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 120static struct notifier_block sctp_inet6addr_notifier = { 121 .notifier_call = sctp_inet6addr_event, 122}; 123 124/* ICMP error handler. */ 125static 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 185out_unlock: 186 sctp_err_finish(sk, transport); 187out: 188 if (likely(idev != NULL)) 189 in6_dev_put(idev); 190 191 return ret; 192} 193 194static 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, sk->sk_priority); 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 */ 226static 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 flowi _fl; 232 struct flowi6 *fl6 = &_fl.u.ip6; 233 struct sctp_bind_addr *bp; 234 struct ipv6_pinfo *np = inet6_sk(sk); 235 struct sctp_sockaddr_entry *laddr; 236 union sctp_addr *daddr = &t->ipaddr; 237 union sctp_addr dst_saddr; 238 struct in6_addr *final_p, final; 239 enum sctp_scope scope; 240 __u8 matchlen = 0; 241 242 memset(&_fl, 0, sizeof(_fl)); 243 fl6->daddr = daddr->v6.sin6_addr; 244 fl6->fl6_dport = daddr->v6.sin6_port; 245 fl6->flowi6_proto = IPPROTO_SCTP; 246 if (ipv6_addr_type(&daddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 247 fl6->flowi6_oif = daddr->v6.sin6_scope_id; 248 else if (asoc) 249 fl6->flowi6_oif = asoc->base.sk->sk_bound_dev_if; 250 if (t->flowlabel & SCTP_FLOWLABEL_SET_MASK) 251 fl6->flowlabel = htonl(t->flowlabel & SCTP_FLOWLABEL_VAL_MASK); 252 253 if (np->sndflow && (fl6->flowlabel & IPV6_FLOWLABEL_MASK)) { 254 struct ip6_flowlabel *flowlabel; 255 256 flowlabel = fl6_sock_lookup(sk, fl6->flowlabel); 257 if (IS_ERR(flowlabel)) 258 goto out; 259 fl6_sock_release(flowlabel); 260 } 261 262 pr_debug("%s: dst=%pI6 ", __func__, &fl6->daddr); 263 264 if (asoc) 265 fl6->fl6_sport = htons(asoc->base.bind_addr.port); 266 267 if (saddr) { 268 fl6->saddr = saddr->v6.sin6_addr; 269 if (!fl6->fl6_sport) 270 fl6->fl6_sport = saddr->v6.sin6_port; 271 272 pr_debug("src=%pI6 - ", &fl6->saddr); 273 } 274 275 rcu_read_lock(); 276 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 277 rcu_read_unlock(); 278 279 dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p); 280 if (!asoc || saddr) { 281 t->dst = dst; 282 memcpy(fl, &_fl, sizeof(_fl)); 283 goto out; 284 } 285 286 bp = &asoc->base.bind_addr; 287 scope = sctp_scope(daddr); 288 /* ip6_dst_lookup has filled in the fl6->saddr for us. Check 289 * to see if we can use it. 290 */ 291 if (!IS_ERR(dst)) { 292 /* Walk through the bind address list and look for a bind 293 * address that matches the source address of the returned dst. 294 */ 295 sctp_v6_to_addr(&dst_saddr, &fl6->saddr, htons(bp->port)); 296 rcu_read_lock(); 297 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 298 if (!laddr->valid || laddr->state == SCTP_ADDR_DEL || 299 (laddr->state != SCTP_ADDR_SRC && 300 !asoc->src_out_of_asoc_ok)) 301 continue; 302 303 /* Do not compare against v4 addrs */ 304 if ((laddr->a.sa.sa_family == AF_INET6) && 305 (sctp_v6_cmp_addr(&dst_saddr, &laddr->a))) { 306 rcu_read_unlock(); 307 t->dst = dst; 308 memcpy(fl, &_fl, sizeof(_fl)); 309 goto out; 310 } 311 } 312 rcu_read_unlock(); 313 /* None of the bound addresses match the source address of the 314 * dst. So release it. 315 */ 316 dst_release(dst); 317 dst = NULL; 318 } 319 320 /* Walk through the bind address list and try to get the 321 * best source address for a given destination. 322 */ 323 rcu_read_lock(); 324 list_for_each_entry_rcu(laddr, &bp->address_list, list) { 325 struct dst_entry *bdst; 326 __u8 bmatchlen; 327 328 if (!laddr->valid || 329 laddr->state != SCTP_ADDR_SRC || 330 laddr->a.sa.sa_family != AF_INET6 || 331 scope > sctp_scope(&laddr->a)) 332 continue; 333 334 fl6->saddr = laddr->a.v6.sin6_addr; 335 fl6->fl6_sport = laddr->a.v6.sin6_port; 336 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 337 bdst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p); 338 339 if (IS_ERR(bdst)) 340 continue; 341 342 if (ipv6_chk_addr(dev_net(bdst->dev), 343 &laddr->a.v6.sin6_addr, bdst->dev, 1)) { 344 if (!IS_ERR_OR_NULL(dst)) 345 dst_release(dst); 346 dst = bdst; 347 t->dst = dst; 348 memcpy(fl, &_fl, sizeof(_fl)); 349 break; 350 } 351 352 bmatchlen = sctp_v6_addr_match_len(daddr, &laddr->a); 353 if (matchlen > bmatchlen) { 354 dst_release(bdst); 355 continue; 356 } 357 358 if (!IS_ERR_OR_NULL(dst)) 359 dst_release(dst); 360 dst = bdst; 361 matchlen = bmatchlen; 362 t->dst = dst; 363 memcpy(fl, &_fl, sizeof(_fl)); 364 } 365 rcu_read_unlock(); 366 367out: 368 if (!IS_ERR_OR_NULL(dst)) { 369 struct rt6_info *rt; 370 371 rt = (struct rt6_info *)dst; 372 t->dst_cookie = rt6_get_cookie(rt); 373 pr_debug("rt6_dst:%pI6/%d rt6_src:%pI6\n", 374 &rt->rt6i_dst.addr, rt->rt6i_dst.plen, 375 &fl->u.ip6.saddr); 376 } else { 377 t->dst = NULL; 378 pr_debug("no route\n"); 379 } 380} 381 382/* Returns the number of consecutive initial bits that match in the 2 ipv6 383 * addresses. 384 */ 385static inline int sctp_v6_addr_match_len(union sctp_addr *s1, 386 union sctp_addr *s2) 387{ 388 return ipv6_addr_diff(&s1->v6.sin6_addr, &s2->v6.sin6_addr); 389} 390 391/* Fills in the source address(saddr) based on the destination address(daddr) 392 * and asoc's bind address list. 393 */ 394static void sctp_v6_get_saddr(struct sctp_sock *sk, 395 struct sctp_transport *t, 396 struct flowi *fl) 397{ 398 struct flowi6 *fl6 = &fl->u.ip6; 399 union sctp_addr *saddr = &t->saddr; 400 401 pr_debug("%s: asoc:%p dst:%p\n", __func__, t->asoc, t->dst); 402 403 if (t->dst) { 404 saddr->v6.sin6_family = AF_INET6; 405 saddr->v6.sin6_addr = fl6->saddr; 406 } 407} 408 409/* Make a copy of all potential local addresses. */ 410static void sctp_v6_copy_addrlist(struct list_head *addrlist, 411 struct net_device *dev) 412{ 413 struct inet6_dev *in6_dev; 414 struct inet6_ifaddr *ifp; 415 struct sctp_sockaddr_entry *addr; 416 417 rcu_read_lock(); 418 if ((in6_dev = __in6_dev_get(dev)) == NULL) { 419 rcu_read_unlock(); 420 return; 421 } 422 423 read_lock_bh(&in6_dev->lock); 424 list_for_each_entry(ifp, &in6_dev->addr_list, if_list) { 425 /* Add the address to the local list. */ 426 addr = kzalloc(sizeof(*addr), GFP_ATOMIC); 427 if (addr) { 428 addr->a.v6.sin6_family = AF_INET6; 429 addr->a.v6.sin6_addr = ifp->addr; 430 addr->a.v6.sin6_scope_id = dev->ifindex; 431 addr->valid = 1; 432 INIT_LIST_HEAD(&addr->list); 433 list_add_tail(&addr->list, addrlist); 434 } 435 } 436 437 read_unlock_bh(&in6_dev->lock); 438 rcu_read_unlock(); 439} 440 441/* Copy over any ip options */ 442static void sctp_v6_copy_ip_options(struct sock *sk, struct sock *newsk) 443{ 444 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 445 struct ipv6_txoptions *opt; 446 447 newnp = inet6_sk(newsk); 448 449 rcu_read_lock(); 450 opt = rcu_dereference(np->opt); 451 if (opt) { 452 opt = ipv6_dup_options(newsk, opt); 453 if (!opt) 454 pr_err("%s: Failed to copy ip options\n", __func__); 455 } 456 RCU_INIT_POINTER(newnp->opt, opt); 457 rcu_read_unlock(); 458} 459 460/* Account for the IP options */ 461static int sctp_v6_ip_options_len(struct sock *sk) 462{ 463 struct ipv6_pinfo *np = inet6_sk(sk); 464 struct ipv6_txoptions *opt; 465 int len = 0; 466 467 rcu_read_lock(); 468 opt = rcu_dereference(np->opt); 469 if (opt) 470 len = opt->opt_flen + opt->opt_nflen; 471 472 rcu_read_unlock(); 473 return len; 474} 475 476/* Initialize a sockaddr_storage from in incoming skb. */ 477static void sctp_v6_from_skb(union sctp_addr *addr, struct sk_buff *skb, 478 int is_saddr) 479{ 480 /* Always called on head skb, so this is safe */ 481 struct sctphdr *sh = sctp_hdr(skb); 482 struct sockaddr_in6 *sa = &addr->v6; 483 484 addr->v6.sin6_family = AF_INET6; 485 addr->v6.sin6_flowinfo = 0; /* FIXME */ 486 addr->v6.sin6_scope_id = ((struct inet6_skb_parm *)skb->cb)->iif; 487 488 if (is_saddr) { 489 sa->sin6_port = sh->source; 490 sa->sin6_addr = ipv6_hdr(skb)->saddr; 491 } else { 492 sa->sin6_port = sh->dest; 493 sa->sin6_addr = ipv6_hdr(skb)->daddr; 494 } 495} 496 497/* Initialize an sctp_addr from a socket. */ 498static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk) 499{ 500 addr->v6.sin6_family = AF_INET6; 501 addr->v6.sin6_port = 0; 502 addr->v6.sin6_addr = sk->sk_v6_rcv_saddr; 503} 504 505/* Initialize sk->sk_rcv_saddr from sctp_addr. */ 506static void sctp_v6_to_sk_saddr(union sctp_addr *addr, struct sock *sk) 507{ 508 if (addr->sa.sa_family == AF_INET) { 509 sk->sk_v6_rcv_saddr.s6_addr32[0] = 0; 510 sk->sk_v6_rcv_saddr.s6_addr32[1] = 0; 511 sk->sk_v6_rcv_saddr.s6_addr32[2] = htonl(0x0000ffff); 512 sk->sk_v6_rcv_saddr.s6_addr32[3] = 513 addr->v4.sin_addr.s_addr; 514 } else { 515 sk->sk_v6_rcv_saddr = addr->v6.sin6_addr; 516 } 517} 518 519/* Initialize sk->sk_daddr from sctp_addr. */ 520static void sctp_v6_to_sk_daddr(union sctp_addr *addr, struct sock *sk) 521{ 522 if (addr->sa.sa_family == AF_INET) { 523 sk->sk_v6_daddr.s6_addr32[0] = 0; 524 sk->sk_v6_daddr.s6_addr32[1] = 0; 525 sk->sk_v6_daddr.s6_addr32[2] = htonl(0x0000ffff); 526 sk->sk_v6_daddr.s6_addr32[3] = addr->v4.sin_addr.s_addr; 527 } else { 528 sk->sk_v6_daddr = addr->v6.sin6_addr; 529 } 530} 531 532/* Initialize a sctp_addr from an address parameter. */ 533static bool sctp_v6_from_addr_param(union sctp_addr *addr, 534 union sctp_addr_param *param, 535 __be16 port, int iif) 536{ 537 if (ntohs(param->v6.param_hdr.length) < sizeof(struct sctp_ipv6addr_param)) 538 return false; 539 540 addr->v6.sin6_family = AF_INET6; 541 addr->v6.sin6_port = port; 542 addr->v6.sin6_flowinfo = 0; /* BUG */ 543 addr->v6.sin6_addr = param->v6.addr; 544 addr->v6.sin6_scope_id = iif; 545 546 return true; 547} 548 549/* Initialize an address parameter from a sctp_addr and return the length 550 * of the address parameter. 551 */ 552static int sctp_v6_to_addr_param(const union sctp_addr *addr, 553 union sctp_addr_param *param) 554{ 555 int length = sizeof(struct sctp_ipv6addr_param); 556 557 param->v6.param_hdr.type = SCTP_PARAM_IPV6_ADDRESS; 558 param->v6.param_hdr.length = htons(length); 559 param->v6.addr = addr->v6.sin6_addr; 560 561 return length; 562} 563 564/* Initialize a sctp_addr from struct in6_addr. */ 565static void sctp_v6_to_addr(union sctp_addr *addr, struct in6_addr *saddr, 566 __be16 port) 567{ 568 addr->sa.sa_family = AF_INET6; 569 addr->v6.sin6_port = port; 570 addr->v6.sin6_flowinfo = 0; 571 addr->v6.sin6_addr = *saddr; 572 addr->v6.sin6_scope_id = 0; 573} 574 575static int __sctp_v6_cmp_addr(const union sctp_addr *addr1, 576 const union sctp_addr *addr2) 577{ 578 if (addr1->sa.sa_family != addr2->sa.sa_family) { 579 if (addr1->sa.sa_family == AF_INET && 580 addr2->sa.sa_family == AF_INET6 && 581 ipv6_addr_v4mapped(&addr2->v6.sin6_addr) && 582 addr2->v6.sin6_addr.s6_addr32[3] == 583 addr1->v4.sin_addr.s_addr) 584 return 1; 585 586 if (addr2->sa.sa_family == AF_INET && 587 addr1->sa.sa_family == AF_INET6 && 588 ipv6_addr_v4mapped(&addr1->v6.sin6_addr) && 589 addr1->v6.sin6_addr.s6_addr32[3] == 590 addr2->v4.sin_addr.s_addr) 591 return 1; 592 593 return 0; 594 } 595 596 if (!ipv6_addr_equal(&addr1->v6.sin6_addr, &addr2->v6.sin6_addr)) 597 return 0; 598 599 /* If this is a linklocal address, compare the scope_id. */ 600 if ((ipv6_addr_type(&addr1->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) && 601 addr1->v6.sin6_scope_id && addr2->v6.sin6_scope_id && 602 addr1->v6.sin6_scope_id != addr2->v6.sin6_scope_id) 603 return 0; 604 605 return 1; 606} 607 608/* Compare addresses exactly. 609 * v4-mapped-v6 is also in consideration. 610 */ 611static int sctp_v6_cmp_addr(const union sctp_addr *addr1, 612 const union sctp_addr *addr2) 613{ 614 return __sctp_v6_cmp_addr(addr1, addr2) && 615 addr1->v6.sin6_port == addr2->v6.sin6_port; 616} 617 618/* Initialize addr struct to INADDR_ANY. */ 619static void sctp_v6_inaddr_any(union sctp_addr *addr, __be16 port) 620{ 621 memset(addr, 0x00, sizeof(union sctp_addr)); 622 addr->v6.sin6_family = AF_INET6; 623 addr->v6.sin6_port = port; 624} 625 626/* Is this a wildcard address? */ 627static int sctp_v6_is_any(const union sctp_addr *addr) 628{ 629 return ipv6_addr_any(&addr->v6.sin6_addr); 630} 631 632/* Should this be available for binding? */ 633static int sctp_v6_available(union sctp_addr *addr, struct sctp_sock *sp) 634{ 635 int type; 636 struct net *net = sock_net(&sp->inet.sk); 637 const struct in6_addr *in6 = (const struct in6_addr *)&addr->v6.sin6_addr; 638 639 type = ipv6_addr_type(in6); 640 if (IPV6_ADDR_ANY == type) 641 return 1; 642 if (type == IPV6_ADDR_MAPPED) { 643 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 644 return 0; 645 sctp_v6_map_v4(addr); 646 return sctp_get_af_specific(AF_INET)->available(addr, sp); 647 } 648 if (!(type & IPV6_ADDR_UNICAST)) 649 return 0; 650 651 return ipv6_can_nonlocal_bind(net, &sp->inet) || 652 ipv6_chk_addr(net, in6, NULL, 0); 653} 654 655/* This function checks if the address is a valid address to be used for 656 * SCTP. 657 * 658 * Output: 659 * Return 0 - If the address is a non-unicast or an illegal address. 660 * Return 1 - If the address is a unicast. 661 */ 662static int sctp_v6_addr_valid(union sctp_addr *addr, 663 struct sctp_sock *sp, 664 const struct sk_buff *skb) 665{ 666 int ret = ipv6_addr_type(&addr->v6.sin6_addr); 667 668 /* Support v4-mapped-v6 address. */ 669 if (ret == IPV6_ADDR_MAPPED) { 670 /* Note: This routine is used in input, so v4-mapped-v6 671 * are disallowed here when there is no sctp_sock. 672 */ 673 if (sp && ipv6_only_sock(sctp_opt2sk(sp))) 674 return 0; 675 sctp_v6_map_v4(addr); 676 return sctp_get_af_specific(AF_INET)->addr_valid(addr, sp, skb); 677 } 678 679 /* Is this a non-unicast address */ 680 if (!(ret & IPV6_ADDR_UNICAST)) 681 return 0; 682 683 return 1; 684} 685 686/* What is the scope of 'addr'? */ 687static enum sctp_scope sctp_v6_scope(union sctp_addr *addr) 688{ 689 enum sctp_scope retval; 690 int v6scope; 691 692 /* The IPv6 scope is really a set of bit fields. 693 * See IFA_* in <net/if_inet6.h>. Map to a generic SCTP scope. 694 */ 695 696 v6scope = ipv6_addr_scope(&addr->v6.sin6_addr); 697 switch (v6scope) { 698 case IFA_HOST: 699 retval = SCTP_SCOPE_LOOPBACK; 700 break; 701 case IFA_LINK: 702 retval = SCTP_SCOPE_LINK; 703 break; 704 case IFA_SITE: 705 retval = SCTP_SCOPE_PRIVATE; 706 break; 707 default: 708 retval = SCTP_SCOPE_GLOBAL; 709 break; 710 } 711 712 return retval; 713} 714 715/* Create and initialize a new sk for the socket to be returned by accept(). */ 716static struct sock *sctp_v6_create_accept_sk(struct sock *sk, 717 struct sctp_association *asoc, 718 bool kern) 719{ 720 struct sock *newsk; 721 struct ipv6_pinfo *newnp, *np = inet6_sk(sk); 722 struct sctp6_sock *newsctp6sk; 723 724 newsk = sk_alloc(sock_net(sk), PF_INET6, GFP_KERNEL, sk->sk_prot, kern); 725 if (!newsk) 726 goto out; 727 728 sock_init_data(NULL, newsk); 729 730 sctp_copy_sock(newsk, sk, asoc); 731 sock_reset_flag(sk, SOCK_ZAPPED); 732 733 newsctp6sk = (struct sctp6_sock *)newsk; 734 inet_sk(newsk)->pinet6 = &newsctp6sk->inet6; 735 736 sctp_sk(newsk)->v4mapped = sctp_sk(sk)->v4mapped; 737 738 newnp = inet6_sk(newsk); 739 740 memcpy(newnp, np, sizeof(struct ipv6_pinfo)); 741 newnp->ipv6_mc_list = NULL; 742 newnp->ipv6_ac_list = NULL; 743 newnp->ipv6_fl_list = NULL; 744 745 sctp_v6_copy_ip_options(sk, newsk); 746 747 /* Initialize sk's sport, dport, rcv_saddr and daddr for getsockname() 748 * and getpeername(). 749 */ 750 sctp_v6_to_sk_daddr(&asoc->peer.primary_addr, newsk); 751 752 newsk->sk_v6_rcv_saddr = sk->sk_v6_rcv_saddr; 753 754 sk_refcnt_debug_inc(newsk); 755 756 if (newsk->sk_prot->init(newsk)) { 757 sk_common_release(newsk); 758 newsk = NULL; 759 } 760 761out: 762 return newsk; 763} 764 765/* Format a sockaddr for return to user space. This makes sure the return is 766 * AF_INET or AF_INET6 depending on the SCTP_I_WANT_MAPPED_V4_ADDR option. 767 */ 768static int sctp_v6_addr_to_user(struct sctp_sock *sp, union sctp_addr *addr) 769{ 770 if (sp->v4mapped) { 771 if (addr->sa.sa_family == AF_INET) 772 sctp_v4_map_v6(addr); 773 } else { 774 if (addr->sa.sa_family == AF_INET6 && 775 ipv6_addr_v4mapped(&addr->v6.sin6_addr)) 776 sctp_v6_map_v4(addr); 777 } 778 779 if (addr->sa.sa_family == AF_INET) { 780 memset(addr->v4.sin_zero, 0, sizeof(addr->v4.sin_zero)); 781 return sizeof(struct sockaddr_in); 782 } 783 return sizeof(struct sockaddr_in6); 784} 785 786/* Where did this skb come from? */ 787static int sctp_v6_skb_iif(const struct sk_buff *skb) 788{ 789 return IP6CB(skb)->iif; 790} 791 792/* Was this packet marked by Explicit Congestion Notification? */ 793static int sctp_v6_is_ce(const struct sk_buff *skb) 794{ 795 return *((__u32 *)(ipv6_hdr(skb))) & (__force __u32)htonl(1 << 20); 796} 797 798/* Dump the v6 addr to the seq file. */ 799static void sctp_v6_seq_dump_addr(struct seq_file *seq, union sctp_addr *addr) 800{ 801 seq_printf(seq, "%pI6 ", &addr->v6.sin6_addr); 802} 803 804static void sctp_v6_ecn_capable(struct sock *sk) 805{ 806 inet6_sk(sk)->tclass |= INET_ECN_ECT_0; 807} 808 809/* Initialize a PF_INET msgname from a ulpevent. */ 810static void sctp_inet6_event_msgname(struct sctp_ulpevent *event, 811 char *msgname, int *addrlen) 812{ 813 union sctp_addr *addr; 814 struct sctp_association *asoc; 815 union sctp_addr *paddr; 816 817 if (!msgname) 818 return; 819 820 addr = (union sctp_addr *)msgname; 821 asoc = event->asoc; 822 paddr = &asoc->peer.primary_addr; 823 824 if (paddr->sa.sa_family == AF_INET) { 825 addr->v4.sin_family = AF_INET; 826 addr->v4.sin_port = htons(asoc->peer.port); 827 addr->v4.sin_addr = paddr->v4.sin_addr; 828 } else { 829 addr->v6.sin6_family = AF_INET6; 830 addr->v6.sin6_flowinfo = 0; 831 if (ipv6_addr_type(&paddr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 832 addr->v6.sin6_scope_id = paddr->v6.sin6_scope_id; 833 else 834 addr->v6.sin6_scope_id = 0; 835 addr->v6.sin6_port = htons(asoc->peer.port); 836 addr->v6.sin6_addr = paddr->v6.sin6_addr; 837 } 838 839 *addrlen = sctp_v6_addr_to_user(sctp_sk(asoc->base.sk), addr); 840} 841 842/* Initialize a msg_name from an inbound skb. */ 843static void sctp_inet6_skb_msgname(struct sk_buff *skb, char *msgname, 844 int *addr_len) 845{ 846 union sctp_addr *addr; 847 struct sctphdr *sh; 848 849 if (!msgname) 850 return; 851 852 addr = (union sctp_addr *)msgname; 853 sh = sctp_hdr(skb); 854 855 if (ip_hdr(skb)->version == 4) { 856 addr->v4.sin_family = AF_INET; 857 addr->v4.sin_port = sh->source; 858 addr->v4.sin_addr.s_addr = ip_hdr(skb)->saddr; 859 } else { 860 addr->v6.sin6_family = AF_INET6; 861 addr->v6.sin6_flowinfo = 0; 862 addr->v6.sin6_port = sh->source; 863 addr->v6.sin6_addr = ipv6_hdr(skb)->saddr; 864 if (ipv6_addr_type(&addr->v6.sin6_addr) & IPV6_ADDR_LINKLOCAL) 865 addr->v6.sin6_scope_id = sctp_v6_skb_iif(skb); 866 else 867 addr->v6.sin6_scope_id = 0; 868 } 869 870 *addr_len = sctp_v6_addr_to_user(sctp_sk(skb->sk), addr); 871} 872 873/* Do we support this AF? */ 874static int sctp_inet6_af_supported(sa_family_t family, struct sctp_sock *sp) 875{ 876 switch (family) { 877 case AF_INET6: 878 return 1; 879 /* v4-mapped-v6 addresses */ 880 case AF_INET: 881 if (!__ipv6_only_sock(sctp_opt2sk(sp))) 882 return 1; 883 fallthrough; 884 default: 885 return 0; 886 } 887} 888 889/* Address matching with wildcards allowed. This extra level 890 * of indirection lets us choose whether a PF_INET6 should 891 * disallow any v4 addresses if we so choose. 892 */ 893static int sctp_inet6_cmp_addr(const union sctp_addr *addr1, 894 const union sctp_addr *addr2, 895 struct sctp_sock *opt) 896{ 897 struct sock *sk = sctp_opt2sk(opt); 898 struct sctp_af *af1, *af2; 899 900 af1 = sctp_get_af_specific(addr1->sa.sa_family); 901 af2 = sctp_get_af_specific(addr2->sa.sa_family); 902 903 if (!af1 || !af2) 904 return 0; 905 906 /* If the socket is IPv6 only, v4 addrs will not match */ 907 if (__ipv6_only_sock(sk) && af1 != af2) 908 return 0; 909 910 /* Today, wildcard AF_INET/AF_INET6. */ 911 if (sctp_is_any(sk, addr1) || sctp_is_any(sk, addr2)) 912 return 1; 913 914 if (addr1->sa.sa_family == AF_INET && addr2->sa.sa_family == AF_INET) 915 return addr1->v4.sin_addr.s_addr == addr2->v4.sin_addr.s_addr; 916 917 return __sctp_v6_cmp_addr(addr1, addr2); 918} 919 920/* Verify that the provided sockaddr looks bindable. Common verification, 921 * has already been taken care of. 922 */ 923static int sctp_inet6_bind_verify(struct sctp_sock *opt, union sctp_addr *addr) 924{ 925 struct sctp_af *af; 926 927 /* ASSERT: address family has already been verified. */ 928 if (addr->sa.sa_family != AF_INET6) 929 af = sctp_get_af_specific(addr->sa.sa_family); 930 else { 931 int type = ipv6_addr_type(&addr->v6.sin6_addr); 932 struct net_device *dev; 933 934 if (type & IPV6_ADDR_LINKLOCAL) { 935 struct net *net; 936 if (!addr->v6.sin6_scope_id) 937 return 0; 938 net = sock_net(&opt->inet.sk); 939 rcu_read_lock(); 940 dev = dev_get_by_index_rcu(net, addr->v6.sin6_scope_id); 941 if (!dev || !(ipv6_can_nonlocal_bind(net, &opt->inet) || 942 ipv6_chk_addr(net, &addr->v6.sin6_addr, 943 dev, 0))) { 944 rcu_read_unlock(); 945 return 0; 946 } 947 rcu_read_unlock(); 948 } 949 950 af = opt->pf->af; 951 } 952 return af->available(addr, opt); 953} 954 955/* Verify that the provided sockaddr looks sendable. Common verification, 956 * has already been taken care of. 957 */ 958static int sctp_inet6_send_verify(struct sctp_sock *opt, union sctp_addr *addr) 959{ 960 struct sctp_af *af = NULL; 961 962 /* ASSERT: address family has already been verified. */ 963 if (addr->sa.sa_family != AF_INET6) 964 af = sctp_get_af_specific(addr->sa.sa_family); 965 else { 966 int type = ipv6_addr_type(&addr->v6.sin6_addr); 967 struct net_device *dev; 968 969 if (type & IPV6_ADDR_LINKLOCAL) { 970 if (!addr->v6.sin6_scope_id) 971 return 0; 972 rcu_read_lock(); 973 dev = dev_get_by_index_rcu(sock_net(&opt->inet.sk), 974 addr->v6.sin6_scope_id); 975 rcu_read_unlock(); 976 if (!dev) 977 return 0; 978 } 979 af = opt->pf->af; 980 } 981 982 return af != NULL; 983} 984 985/* Fill in Supported Address Type information for INIT and INIT-ACK 986 * chunks. Note: In the future, we may want to look at sock options 987 * to determine whether a PF_INET6 socket really wants to have IPV4 988 * addresses. 989 * Returns number of addresses supported. 990 */ 991static int sctp_inet6_supported_addrs(const struct sctp_sock *opt, 992 __be16 *types) 993{ 994 types[0] = SCTP_PARAM_IPV6_ADDRESS; 995 if (!opt || !ipv6_only_sock(sctp_opt2sk(opt))) { 996 types[1] = SCTP_PARAM_IPV4_ADDRESS; 997 return 2; 998 } 999 return 1; 1000} 1001 1002/* Handle SCTP_I_WANT_MAPPED_V4_ADDR for getpeername() and getsockname() */ 1003static int sctp_getname(struct socket *sock, struct sockaddr *uaddr, 1004 int peer) 1005{ 1006 int rc; 1007 1008 rc = inet6_getname(sock, uaddr, peer); 1009 1010 if (rc < 0) 1011 return rc; 1012 1013 rc = sctp_v6_addr_to_user(sctp_sk(sock->sk), 1014 (union sctp_addr *)uaddr); 1015 1016 return rc; 1017} 1018 1019static const struct proto_ops inet6_seqpacket_ops = { 1020 .family = PF_INET6, 1021 .owner = THIS_MODULE, 1022 .release = inet6_release, 1023 .bind = inet6_bind, 1024 .connect = sctp_inet_connect, 1025 .socketpair = sock_no_socketpair, 1026 .accept = inet_accept, 1027 .getname = sctp_getname, 1028 .poll = sctp_poll, 1029 .ioctl = inet6_ioctl, 1030 .gettstamp = sock_gettstamp, 1031 .listen = sctp_inet_listen, 1032 .shutdown = inet_shutdown, 1033 .setsockopt = sock_common_setsockopt, 1034 .getsockopt = sock_common_getsockopt, 1035 .sendmsg = inet_sendmsg, 1036 .recvmsg = inet_recvmsg, 1037 .mmap = sock_no_mmap, 1038#ifdef CONFIG_COMPAT 1039 .compat_ioctl = inet6_compat_ioctl, 1040#endif 1041}; 1042 1043static struct inet_protosw sctpv6_seqpacket_protosw = { 1044 .type = SOCK_SEQPACKET, 1045 .protocol = IPPROTO_SCTP, 1046 .prot = &sctpv6_prot, 1047 .ops = &inet6_seqpacket_ops, 1048 .flags = SCTP_PROTOSW_FLAG 1049}; 1050static struct inet_protosw sctpv6_stream_protosw = { 1051 .type = SOCK_STREAM, 1052 .protocol = IPPROTO_SCTP, 1053 .prot = &sctpv6_prot, 1054 .ops = &inet6_seqpacket_ops, 1055 .flags = SCTP_PROTOSW_FLAG, 1056}; 1057 1058static int sctp6_rcv(struct sk_buff *skb) 1059{ 1060 return sctp_rcv(skb) ? -1 : 0; 1061} 1062 1063static const struct inet6_protocol sctpv6_protocol = { 1064 .handler = sctp6_rcv, 1065 .err_handler = sctp_v6_err, 1066 .flags = INET6_PROTO_NOPOLICY | INET6_PROTO_FINAL, 1067}; 1068 1069static struct sctp_af sctp_af_inet6 = { 1070 .sa_family = AF_INET6, 1071 .sctp_xmit = sctp_v6_xmit, 1072 .setsockopt = ipv6_setsockopt, 1073 .getsockopt = ipv6_getsockopt, 1074 .get_dst = sctp_v6_get_dst, 1075 .get_saddr = sctp_v6_get_saddr, 1076 .copy_addrlist = sctp_v6_copy_addrlist, 1077 .from_skb = sctp_v6_from_skb, 1078 .from_sk = sctp_v6_from_sk, 1079 .from_addr_param = sctp_v6_from_addr_param, 1080 .to_addr_param = sctp_v6_to_addr_param, 1081 .cmp_addr = sctp_v6_cmp_addr, 1082 .scope = sctp_v6_scope, 1083 .addr_valid = sctp_v6_addr_valid, 1084 .inaddr_any = sctp_v6_inaddr_any, 1085 .is_any = sctp_v6_is_any, 1086 .available = sctp_v6_available, 1087 .skb_iif = sctp_v6_skb_iif, 1088 .is_ce = sctp_v6_is_ce, 1089 .seq_dump_addr = sctp_v6_seq_dump_addr, 1090 .ecn_capable = sctp_v6_ecn_capable, 1091 .net_header_len = sizeof(struct ipv6hdr), 1092 .sockaddr_len = sizeof(struct sockaddr_in6), 1093 .ip_options_len = sctp_v6_ip_options_len, 1094}; 1095 1096static struct sctp_pf sctp_pf_inet6 = { 1097 .event_msgname = sctp_inet6_event_msgname, 1098 .skb_msgname = sctp_inet6_skb_msgname, 1099 .af_supported = sctp_inet6_af_supported, 1100 .cmp_addr = sctp_inet6_cmp_addr, 1101 .bind_verify = sctp_inet6_bind_verify, 1102 .send_verify = sctp_inet6_send_verify, 1103 .supported_addrs = sctp_inet6_supported_addrs, 1104 .create_accept_sk = sctp_v6_create_accept_sk, 1105 .addr_to_user = sctp_v6_addr_to_user, 1106 .to_sk_saddr = sctp_v6_to_sk_saddr, 1107 .to_sk_daddr = sctp_v6_to_sk_daddr, 1108 .copy_ip_options = sctp_v6_copy_ip_options, 1109 .af = &sctp_af_inet6, 1110}; 1111 1112/* Initialize IPv6 support and register with socket layer. */ 1113void sctp_v6_pf_init(void) 1114{ 1115 /* Register the SCTP specific PF_INET6 functions. */ 1116 sctp_register_pf(&sctp_pf_inet6, PF_INET6); 1117 1118 /* Register the SCTP specific AF_INET6 functions. */ 1119 sctp_register_af(&sctp_af_inet6); 1120} 1121 1122void sctp_v6_pf_exit(void) 1123{ 1124 list_del(&sctp_af_inet6.list); 1125} 1126 1127/* Initialize IPv6 support and register with socket layer. */ 1128int sctp_v6_protosw_init(void) 1129{ 1130 int rc; 1131 1132 rc = proto_register(&sctpv6_prot, 1); 1133 if (rc) 1134 return rc; 1135 1136 /* Add SCTPv6(UDP and TCP style) to inetsw6 linked list. */ 1137 inet6_register_protosw(&sctpv6_seqpacket_protosw); 1138 inet6_register_protosw(&sctpv6_stream_protosw); 1139 1140 return 0; 1141} 1142 1143void sctp_v6_protosw_exit(void) 1144{ 1145 inet6_unregister_protosw(&sctpv6_seqpacket_protosw); 1146 inet6_unregister_protosw(&sctpv6_stream_protosw); 1147 proto_unregister(&sctpv6_prot); 1148} 1149 1150 1151/* Register with inet6 layer. */ 1152int sctp_v6_add_protocol(void) 1153{ 1154 /* Register notifier for inet6 address additions/deletions. */ 1155 register_inet6addr_notifier(&sctp_inet6addr_notifier); 1156 1157 if (inet6_add_protocol(&sctpv6_protocol, IPPROTO_SCTP) < 0) 1158 return -EAGAIN; 1159 1160 return 0; 1161} 1162 1163/* Unregister with inet6 layer. */ 1164void sctp_v6_del_protocol(void) 1165{ 1166 inet6_del_protocol(&sctpv6_protocol, IPPROTO_SCTP); 1167 unregister_inet6addr_notifier(&sctp_inet6addr_notifier); 1168} 1169