in6_src.c revision 1.36
1/* $OpenBSD: in6_src.c,v 1.36 2013/11/11 09:15:35 mpi Exp $ */ 2/* $KAME: in6_src.c,v 1.36 2001/02/06 04:08:17 itojun Exp $ */ 3 4/* 5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the project nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33/* 34 * Copyright (c) 1982, 1986, 1991, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * 61 * @(#)in_pcb.c 8.2 (Berkeley) 1/4/94 62 */ 63 64#include <sys/param.h> 65#include <sys/systm.h> 66#include <sys/malloc.h> 67#include <sys/mbuf.h> 68#include <sys/protosw.h> 69#include <sys/socket.h> 70#include <sys/socketvar.h> 71#include <sys/ioctl.h> 72#include <sys/errno.h> 73#include <sys/time.h> 74 75#include <net/if.h> 76#include <net/route.h> 77 78#include <netinet/in.h> 79#include <netinet/in_systm.h> 80#include <netinet/ip.h> 81#include <netinet/in_pcb.h> 82#include <netinet6/in6_var.h> 83#include <netinet/ip6.h> 84#include <netinet6/ip6_var.h> 85#include <netinet6/nd6.h> 86 87int in6_selectif(struct sockaddr_in6 *, struct ip6_pktopts *, 88 struct ip6_moptions *, struct route_in6 *, struct ifnet **, u_int); 89int selectroute(struct sockaddr_in6 *, struct ip6_pktopts *, 90 struct ip6_moptions *, struct route_in6 *, struct ifnet **, 91 struct rtentry **, int, u_int); 92 93/* 94 * Return an IPv6 address, which is the most appropriate for a given 95 * destination and user specified options. 96 * If necessary, this function lookups the routing table and returns 97 * an entry to the caller for later use. 98 */ 99struct in6_addr * 100in6_selectsrc(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, 101 struct ip6_moptions *mopts, struct route_in6 *ro, struct in6_addr *laddr, 102 int *errorp, u_int rtableid) 103{ 104 struct ifnet *ifp = NULL; 105 struct in6_addr *dst; 106 struct in6_ifaddr *ia6 = NULL; 107 struct in6_pktinfo *pi = NULL; 108 109 dst = &dstsock->sin6_addr; 110 *errorp = 0; 111 112 /* 113 * If the source address is explicitly specified by the caller, 114 * check if the requested source address is indeed a unicast address 115 * assigned to the node, and can be used as the packet's source 116 * address. If everything is okay, use the address as source. 117 */ 118 if (opts && (pi = opts->ip6po_pktinfo) && 119 !IN6_IS_ADDR_UNSPECIFIED(&pi->ipi6_addr)) { 120 struct sockaddr_in6 sa6; 121 122 /* get the outgoing interface */ 123 if ((*errorp = in6_selectif(dstsock, opts, mopts, ro, 124 &ifp, rtableid)) != 0) 125 return (NULL); 126 127 bzero(&sa6, sizeof(sa6)); 128 sa6.sin6_family = AF_INET6; 129 sa6.sin6_len = sizeof(sa6); 130 sa6.sin6_addr = pi->ipi6_addr; 131 132 if (ifp && IN6_IS_SCOPE_EMBED(&sa6.sin6_addr)) 133 sa6.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 134 135 ia6 = ifatoia6(ifa_ifwithaddr(sin6tosa(&sa6), rtableid)); 136 if (ia6 == NULL || 137 (ia6->ia6_flags & (IN6_IFF_ANYCAST | IN6_IFF_NOTREADY))) { 138 *errorp = EADDRNOTAVAIL; 139 return (NULL); 140 } 141 142 pi->ipi6_addr = sa6.sin6_addr; /* XXX: this overrides pi */ 143 144 return (&pi->ipi6_addr); 145 } 146 147 /* 148 * If the source address is not specified but the socket(if any) 149 * is already bound, use the bound address. 150 */ 151 if (laddr && !IN6_IS_ADDR_UNSPECIFIED(laddr)) 152 return (laddr); 153 154 /* 155 * If the caller doesn't specify the source address but 156 * the outgoing interface, use an address associated with 157 * the interface. 158 */ 159 if (pi && pi->ipi6_ifindex) { 160 ifp = if_get(pi->ipi6_ifindex); 161 if (ifp == NULL) { 162 *errorp = ENXIO; /* XXX: better error? */ 163 return (0); 164 } 165 ia6 = in6_ifawithscope(ifp, dst, rtableid); 166 if (ia6 == 0) { 167 *errorp = EADDRNOTAVAIL; 168 return (0); 169 } 170 return (&ia6->ia_addr.sin6_addr); 171 } 172 173 /* 174 * If the destination address is a link-local unicast address or 175 * a link/interface-local multicast address, and if the outgoing 176 * interface is specified by the sin6_scope_id filed, use an address 177 * associated with the interface. 178 * XXX: We're now trying to define more specific semantics of 179 * sin6_scope_id field, so this part will be rewritten in 180 * the near future. 181 */ 182 if ((IN6_IS_ADDR_LINKLOCAL(dst) || IN6_IS_ADDR_MC_LINKLOCAL(dst) || 183 IN6_IS_ADDR_MC_INTFACELOCAL(dst)) && dstsock->sin6_scope_id) { 184 ifp = if_get(dstsock->sin6_scope_id); 185 if (ifp == NULL) { 186 *errorp = ENXIO; /* XXX: better error? */ 187 return (0); 188 } 189 ia6 = in6_ifawithscope(ifp, dst, rtableid); 190 if (ia6 == 0) { 191 *errorp = EADDRNOTAVAIL; 192 return (0); 193 } 194 return (&ia6->ia_addr.sin6_addr); 195 } 196 197 /* 198 * If the destination address is a multicast address and 199 * the outgoing interface for the address is specified 200 * by the caller, use an address associated with the interface. 201 * Even if the outgoing interface is not specified, we also 202 * choose a loopback interface as the outgoing interface. 203 */ 204 if (IN6_IS_ADDR_MULTICAST(dst)) { 205 ifp = mopts ? mopts->im6o_multicast_ifp : NULL; 206 207 if (!ifp && dstsock->sin6_scope_id) 208 ifp = if_get(htons(dstsock->sin6_scope_id)); 209 210 if (ifp) { 211 ia6 = in6_ifawithscope(ifp, dst, rtableid); 212 if (ia6 == 0) { 213 *errorp = EADDRNOTAVAIL; 214 return (0); 215 } 216 return (&ia6->ia_addr.sin6_addr); 217 } 218 } 219 220 /* 221 * If the next hop address for the packet is specified 222 * by caller, use an address associated with the route 223 * to the next hop. 224 */ 225 { 226 struct sockaddr_in6 *sin6_next; 227 struct rtentry *rt; 228 229 if (opts && opts->ip6po_nexthop) { 230 sin6_next = satosin6(opts->ip6po_nexthop); 231 rt = nd6_lookup(&sin6_next->sin6_addr, 1, NULL); 232 if (rt) { 233 ia6 = in6_ifawithscope(rt->rt_ifp, dst, 234 rtableid); 235 if (ia6 == 0) 236 ia6 = ifatoia6(rt->rt_ifa); 237 } 238 if (ia6 == 0) { 239 *errorp = EADDRNOTAVAIL; 240 return (0); 241 } 242 return (&ia6->ia_addr.sin6_addr); 243 } 244 } 245 246 /* 247 * If route is known or can be allocated now, 248 * our src addr is taken from the i/f, else punt. 249 */ 250 if (ro) { 251 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 252 !IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, dst))) { 253 RTFREE(ro->ro_rt); 254 ro->ro_rt = (struct rtentry *)0; 255 } 256 if (ro->ro_rt == (struct rtentry *)0 || 257 ro->ro_rt->rt_ifp == (struct ifnet *)0) { 258 struct sockaddr_in6 *sa6; 259 260 /* No route yet, so try to acquire one */ 261 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); 262 ro->ro_tableid = rtableid; 263 sa6 = &ro->ro_dst; 264 sa6->sin6_family = AF_INET6; 265 sa6->sin6_len = sizeof(struct sockaddr_in6); 266 sa6->sin6_addr = *dst; 267 sa6->sin6_scope_id = dstsock->sin6_scope_id; 268 if (IN6_IS_ADDR_MULTICAST(dst)) { 269 rtalloc((struct route *)ro); 270 } else { 271 rtalloc_mpath((struct route *)ro, NULL); 272 } 273 } 274 275 /* 276 * in_pcbconnect() checks out IFF_LOOPBACK to skip using 277 * the address. But we don't know why it does so. 278 * It is necessary to ensure the scope even for lo0 279 * so doesn't check out IFF_LOOPBACK. 280 */ 281 282 if (ro->ro_rt) { 283 ia6 = in6_ifawithscope(ro->ro_rt->rt_ifa->ifa_ifp, dst, 284 rtableid); 285 if (ia6 == 0) /* xxx scope error ?*/ 286 ia6 = ifatoia6(ro->ro_rt->rt_ifa); 287 } 288#if 0 289 /* 290 * xxx The followings are necessary? (kazu) 291 * I don't think so. 292 * It's for SO_DONTROUTE option in IPv4.(jinmei) 293 */ 294 if (ia6 == 0) { 295 struct sockaddr_in6 sin6 = {sizeof(sin6), AF_INET6, 0}; 296 297 sin6->sin6_addr = *dst; 298 299 ia6 = ifatoia6(ifa_ifwithdstaddr(sin6tosa(&sin6))); 300 if (ia6 == 0) 301 ia6 = ifatoia6(ifa_ifwithnet(sin6tosa(&sin6))); 302 if (ia6 == 0) 303 return (0); 304 return (&ia6->ia_addr.sin6_addr); 305 } 306#endif /* 0 */ 307 if (ia6 == 0) { 308 *errorp = EHOSTUNREACH; /* no route */ 309 return (0); 310 } 311 return (&ia6->ia_addr.sin6_addr); 312 } 313 314 *errorp = EADDRNOTAVAIL; 315 return (0); 316} 317 318int 319selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, 320 struct ip6_moptions *mopts, struct route_in6 *ro, struct ifnet **retifp, 321 struct rtentry **retrt, int norouteok, u_int rtableid) 322{ 323 int error = 0; 324 struct ifnet *ifp = NULL; 325 struct rtentry *rt = NULL; 326 struct sockaddr_in6 *sin6_next; 327 struct in6_pktinfo *pi = NULL; 328 struct in6_addr *dst; 329 330 dst = &dstsock->sin6_addr; 331 332#if 0 333 char ip[INET6_ADDRSTRLEN]; 334 335 if (dstsock->sin6_addr.s6_addr32[0] == 0 && 336 dstsock->sin6_addr.s6_addr32[1] == 0 && 337 !IN6_IS_ADDR_LOOPBACK(&dstsock->sin6_addr)) { 338 printf("in6_selectroute: strange destination %s\n", 339 inet_ntop(AF_INET6, &dstsock->sin6_addr, ip, sizeof(ip))); 340 } else { 341 printf("in6_selectroute: destination = %s%%%d\n", 342 inet_ntop(AF_INET6, &dstsock->sin6_addr, ip, sizeof(ip)), 343 dstsock->sin6_scope_id); /* for debug */ 344 } 345#endif 346 347 /* If the caller specify the outgoing interface explicitly, use it. */ 348 if (opts && (pi = opts->ip6po_pktinfo) != NULL && pi->ipi6_ifindex) { 349 ifp = if_get(pi->ipi6_ifindex); 350 if (ifp != NULL && 351 (norouteok || retrt == NULL || 352 IN6_IS_ADDR_MULTICAST(dst))) { 353 /* 354 * we do not have to check or get the route for 355 * multicast. 356 */ 357 goto done; 358 } else 359 goto getroute; 360 } 361 362 /* 363 * If the destination address is a multicast address and the outgoing 364 * interface for the address is specified by the caller, use it. 365 */ 366 if (IN6_IS_ADDR_MULTICAST(dst) && 367 mopts != NULL && (ifp = mopts->im6o_multicast_ifp) != NULL) { 368 goto done; /* we do not need a route for multicast. */ 369 } 370 371 getroute: 372 /* 373 * If the next hop address for the packet is specified by the caller, 374 * use it as the gateway. 375 */ 376 if (opts && opts->ip6po_nexthop) { 377 struct route_in6 *ron; 378 379 sin6_next = satosin6(opts->ip6po_nexthop); 380 381 /* at this moment, we only support AF_INET6 next hops */ 382 if (sin6_next->sin6_family != AF_INET6) { 383 error = EAFNOSUPPORT; /* or should we proceed? */ 384 goto done; 385 } 386 387 /* 388 * If the next hop is an IPv6 address, then the node identified 389 * by that address must be a neighbor of the sending host. 390 */ 391 ron = &opts->ip6po_nextroute; 392 if ((ron->ro_rt && 393 (ron->ro_rt->rt_flags & (RTF_UP | RTF_GATEWAY)) != 394 RTF_UP) || 395 !IN6_ARE_ADDR_EQUAL(&ron->ro_dst.sin6_addr, 396 &sin6_next->sin6_addr)) { 397 if (ron->ro_rt) { 398 RTFREE(ron->ro_rt); 399 ron->ro_rt = NULL; 400 } 401 ron->ro_dst = *sin6_next; 402 ron->ro_tableid = rtableid; 403 } 404 if (ron->ro_rt == NULL) { 405 rtalloc((struct route *)ron); /* multi path case? */ 406 if (ron->ro_rt == NULL || 407 (ron->ro_rt->rt_flags & RTF_GATEWAY)) { 408 if (ron->ro_rt) { 409 RTFREE(ron->ro_rt); 410 ron->ro_rt = NULL; 411 } 412 error = EHOSTUNREACH; 413 goto done; 414 } 415 } 416 if (!nd6_is_addr_neighbor(sin6_next, ron->ro_rt->rt_ifp)) { 417 RTFREE(ron->ro_rt); 418 ron->ro_rt = NULL; 419 error = EHOSTUNREACH; 420 goto done; 421 } 422 rt = ron->ro_rt; 423 ifp = rt->rt_ifp; 424 425 /* 426 * When cloning is required, try to allocate a route to the 427 * destination so that the caller can store path MTU 428 * information. 429 */ 430 goto done; 431 } 432 433 /* 434 * Use a cached route if it exists and is valid, else try to allocate 435 * a new one. Note that we should check the address family of the 436 * cached destination, in case of sharing the cache with IPv4. 437 */ 438 if (ro) { 439 if (ro->ro_rt && 440 (!(ro->ro_rt->rt_flags & RTF_UP) || 441 sin6tosa(&ro->ro_dst)->sa_family != AF_INET6 || 442 !IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, dst))) { 443 RTFREE(ro->ro_rt); 444 ro->ro_rt = (struct rtentry *)NULL; 445 } 446 if (ro->ro_rt == (struct rtentry *)NULL) { 447 struct sockaddr_in6 *sa6; 448 449 /* No route yet, so try to acquire one */ 450 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); 451 ro->ro_tableid = rtableid; 452 sa6 = &ro->ro_dst; 453 *sa6 = *dstsock; 454 sa6->sin6_scope_id = 0; 455 ro->ro_tableid = rtableid; 456 rtalloc_mpath((struct route *)ro, NULL); 457 } 458 459 /* 460 * do not care about the result if we have the nexthop 461 * explicitly specified. 462 */ 463 if (opts && opts->ip6po_nexthop) 464 goto done; 465 466 if (ro->ro_rt) { 467 ifp = ro->ro_rt->rt_ifp; 468 469 if (ifp == NULL) { /* can this really happen? */ 470 RTFREE(ro->ro_rt); 471 ro->ro_rt = NULL; 472 } 473 } 474 if (ro->ro_rt == NULL) 475 error = EHOSTUNREACH; 476 rt = ro->ro_rt; 477 478 /* 479 * Check if the outgoing interface conflicts with 480 * the interface specified by ipi6_ifindex (if specified). 481 * Note that loopback interface is always okay. 482 * (this may happen when we are sending a packet to one of 483 * our own addresses.) 484 */ 485 if (opts && opts->ip6po_pktinfo && 486 opts->ip6po_pktinfo->ipi6_ifindex) { 487 if (!(ifp->if_flags & IFF_LOOPBACK) && 488 ifp->if_index != 489 opts->ip6po_pktinfo->ipi6_ifindex) { 490 error = EHOSTUNREACH; 491 goto done; 492 } 493 } 494 } 495 496 done: 497 if (ifp == NULL && rt == NULL) { 498 /* 499 * This can happen if the caller did not pass a cached route 500 * nor any other hints. We treat this case an error. 501 */ 502 error = EHOSTUNREACH; 503 } 504 if (error == EHOSTUNREACH) 505 ip6stat.ip6s_noroute++; 506 507 if (retifp != NULL) 508 *retifp = ifp; 509 if (retrt != NULL) 510 *retrt = rt; /* rt may be NULL */ 511 512 return (error); 513} 514 515int 516in6_selectif(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, 517 struct ip6_moptions *mopts, struct route_in6 *ro, struct ifnet **retifp, 518 u_int rtableid) 519{ 520 struct rtentry *rt = NULL; 521 int error; 522 523 if ((error = selectroute(dstsock, opts, mopts, ro, retifp, 524 &rt, 1, rtableid)) != 0) 525 return (error); 526 527 /* 528 * do not use a rejected or black hole route. 529 * XXX: this check should be done in the L2 output routine. 530 * However, if we skipped this check here, we'd see the following 531 * scenario: 532 * - install a rejected route for a scoped address prefix 533 * (like fe80::/10) 534 * - send a packet to a destination that matches the scoped prefix, 535 * with ambiguity about the scope zone. 536 * - pick the outgoing interface from the route, and disambiguate the 537 * scope zone with the interface. 538 * - ip6_output() would try to get another route with the "new" 539 * destination, which may be valid. 540 * - we'd see no error on output. 541 * Although this may not be very harmful, it should still be confusing. 542 * We thus reject the case here. 543 */ 544 if (rt && (rt->rt_flags & (RTF_REJECT | RTF_BLACKHOLE))) 545 return (rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 546 547 /* 548 * Adjust the "outgoing" interface. If we're going to loop the packet 549 * back to ourselves, the ifp would be the loopback interface. 550 * However, we'd rather know the interface associated to the 551 * destination address (which should probably be one of our own 552 * addresses.) 553 */ 554 if (rt && rt->rt_ifa && rt->rt_ifa->ifa_ifp) 555 *retifp = rt->rt_ifa->ifa_ifp; 556 557 return (0); 558} 559 560int 561in6_selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, 562 struct ip6_moptions *mopts, struct route_in6 *ro, struct ifnet **retifp, 563 struct rtentry **retrt, u_int rtableid) 564{ 565 566 return (selectroute(dstsock, opts, mopts, ro, retifp, retrt, 0, 567 rtableid)); 568} 569 570/* 571 * Default hop limit selection. The precedence is as follows: 572 * 1. Hoplimit value specified via ioctl. 573 * 2. (If the outgoing interface is detected) the current 574 * hop limit of the interface specified by router advertisement. 575 * 3. The system default hoplimit. 576*/ 577int 578in6_selecthlim(struct inpcb *in6p, struct ifnet *ifp) 579{ 580 if (in6p && in6p->inp_hops >= 0) 581 return (in6p->inp_hops); 582 else if (ifp) 583 return (ND_IFINFO(ifp)->chlim); 584 else 585 return (ip6_defhlim); 586} 587 588/* 589 * generate kernel-internal form (scopeid embedded into s6_addr16[1]). 590 * If the address scope of is link-local, embed the interface index in the 591 * address. The routine determines our precedence 592 * between advanced API scope/interface specification and basic API 593 * specification. 594 * 595 * this function should be nuked in the future, when we get rid of 596 * embedded scopeid thing. 597 * 598 * XXX actually, it is over-specification to return ifp against sin6_scope_id. 599 * there can be multiple interfaces that belong to a particular scope zone 600 * (in specification, we have 1:N mapping between a scope zone and interfaces). 601 * we may want to change the function to return something other than ifp. 602 */ 603int 604in6_embedscope(in6, sin6, in6p, ifpp) 605 struct in6_addr *in6; 606 const struct sockaddr_in6 *sin6; 607 struct inpcb *in6p; 608 struct ifnet **ifpp; 609{ 610 struct ifnet *ifp = NULL; 611 u_int32_t scopeid; 612 613 *in6 = sin6->sin6_addr; 614 scopeid = sin6->sin6_scope_id; 615 if (ifpp) 616 *ifpp = NULL; 617 618 /* 619 * don't try to read sin6->sin6_addr beyond here, since the caller may 620 * ask us to overwrite existing sockaddr_in6 621 */ 622 623 if (IN6_IS_SCOPE_EMBED(in6)) { 624 struct in6_pktinfo *pi; 625 626 /* 627 * KAME assumption: link id == interface id 628 */ 629 630 if (in6p && in6p->inp_outputopts6 && 631 (pi = in6p->inp_outputopts6->ip6po_pktinfo) && 632 pi->ipi6_ifindex) { 633 ifp = if_get(pi->ipi6_ifindex); 634 if (ifp == NULL) 635 return ENXIO; /* XXX EINVAL? */ 636 in6->s6_addr16[1] = htons(pi->ipi6_ifindex); 637 } else if (in6p && IN6_IS_ADDR_MULTICAST(in6) && 638 in6p->inp_moptions6 && 639 in6p->inp_moptions6->im6o_multicast_ifp) { 640 ifp = in6p->inp_moptions6->im6o_multicast_ifp; 641 in6->s6_addr16[1] = htons(ifp->if_index); 642 } else if (scopeid) { 643 ifp = if_get(scopeid); 644 if (ifp == NULL) 645 return ENXIO; /* XXX EINVAL? */ 646 /*XXX assignment to 16bit from 32bit variable */ 647 in6->s6_addr16[1] = htons(scopeid & 0xffff); 648 } 649 650 if (ifpp) 651 *ifpp = ifp; 652 } 653 654 return 0; 655} 656 657/* 658 * generate standard sockaddr_in6 from embedded form. 659 * touches sin6_addr and sin6_scope_id only. 660 * 661 * this function should be nuked in the future, when we get rid of 662 * embedded scopeid thing. 663 */ 664int 665in6_recoverscope(struct sockaddr_in6 *sin6, const struct in6_addr *in6, 666 struct ifnet *ifp) 667{ 668 u_int32_t scopeid; 669 670 sin6->sin6_addr = *in6; 671 672 /* 673 * don't try to read *in6 beyond here, since the caller may 674 * ask us to overwrite existing sockaddr_in6 675 */ 676 677 sin6->sin6_scope_id = 0; 678 if (IN6_IS_SCOPE_EMBED(in6)) { 679 /* 680 * KAME assumption: link id == interface id 681 */ 682 scopeid = ntohs(sin6->sin6_addr.s6_addr16[1]); 683 if (scopeid) { 684 /* sanity check */ 685 if (if_get(scopeid) == NULL) 686 return ENXIO; 687 if (ifp && ifp->if_index != scopeid) 688 return ENXIO; 689 sin6->sin6_addr.s6_addr16[1] = 0; 690 sin6->sin6_scope_id = scopeid; 691 } 692 } 693 694 return 0; 695} 696 697/* 698 * just clear the embedded scope identifer. 699 */ 700void 701in6_clearscope(struct in6_addr *addr) 702{ 703 if (IN6_IS_SCOPE_EMBED(addr)) 704 addr->s6_addr16[1] = 0; 705} 706