1 /* $OpenBSD: in6_src.c,v 1.38 2014/03/12 14:15:09 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 87 int in6_selectif(struct sockaddr_in6 *, struct ip6_pktopts *, 88 struct ip6_moptions *, struct route_in6 *, struct ifnet **, u_int); 89 int 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 */ 99 struct in6_addr * 100 in6_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 rtableid); 233 if (rt) { 234 ia6 = in6_ifawithscope(rt->rt_ifp, dst, 235 rtableid); 236 if (ia6 == 0) 237 ia6 = ifatoia6(rt->rt_ifa); 238 } 239 if (ia6 == 0) { 240 *errorp = EADDRNOTAVAIL; 241 return (0); 242 } 243 return (&ia6->ia_addr.sin6_addr); 244 } 245 } 246 247 /* 248 * If route is known or can be allocated now, 249 * our src addr is taken from the i/f, else punt. 250 */ 251 if (ro) { 252 if (ro->ro_rt && ((ro->ro_rt->rt_flags & RTF_UP) == 0 || 253 !IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, dst))) { 254 RTFREE(ro->ro_rt); 255 ro->ro_rt = (struct rtentry *)0; 256 } 257 if (ro->ro_rt == (struct rtentry *)0 || 258 ro->ro_rt->rt_ifp == (struct ifnet *)0) { 259 struct sockaddr_in6 *sa6; 260 261 /* No route yet, so try to acquire one */ 262 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); 263 ro->ro_tableid = rtableid; 264 sa6 = &ro->ro_dst; 265 sa6->sin6_family = AF_INET6; 266 sa6->sin6_len = sizeof(struct sockaddr_in6); 267 sa6->sin6_addr = *dst; 268 sa6->sin6_scope_id = dstsock->sin6_scope_id; 269 if (IN6_IS_ADDR_MULTICAST(dst)) { 270 rtalloc((struct route *)ro); 271 } else { 272 rtalloc_mpath((struct route *)ro, NULL); 273 } 274 } 275 276 /* 277 * in_pcbconnect() checks out IFF_LOOPBACK to skip using 278 * the address. But we don't know why it does so. 279 * It is necessary to ensure the scope even for lo0 280 * so doesn't check out IFF_LOOPBACK. 281 */ 282 283 if (ro->ro_rt) { 284 ia6 = in6_ifawithscope(ro->ro_rt->rt_ifa->ifa_ifp, dst, 285 rtableid); 286 if (ia6 == 0) /* xxx scope error ?*/ 287 ia6 = ifatoia6(ro->ro_rt->rt_ifa); 288 } 289 #if 0 290 /* 291 * xxx The followings are necessary? (kazu) 292 * I don't think so. 293 * It's for SO_DONTROUTE option in IPv4.(jinmei) 294 */ 295 if (ia6 == 0) { 296 struct sockaddr_in6 sin6 = {sizeof(sin6), AF_INET6, 0}; 297 298 sin6->sin6_addr = *dst; 299 300 ia6 = ifatoia6(ifa_ifwithdstaddr(sin6tosa(&sin6))); 301 if (ia6 == 0) 302 ia6 = ifatoia6(ifa_ifwithnet(sin6tosa(&sin6))); 303 if (ia6 == 0) 304 return (0); 305 return (&ia6->ia_addr.sin6_addr); 306 } 307 #endif /* 0 */ 308 if (ia6 == 0) { 309 *errorp = EHOSTUNREACH; /* no route */ 310 return (0); 311 } 312 return (&ia6->ia_addr.sin6_addr); 313 } 314 315 *errorp = EADDRNOTAVAIL; 316 return (0); 317 } 318 319 int 320 selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, 321 struct ip6_moptions *mopts, struct route_in6 *ro, struct ifnet **retifp, 322 struct rtentry **retrt, int norouteok, u_int rtableid) 323 { 324 int error = 0; 325 struct ifnet *ifp = NULL; 326 struct rtentry *rt = NULL; 327 struct sockaddr_in6 *sin6_next; 328 struct in6_pktinfo *pi = NULL; 329 struct in6_addr *dst; 330 331 dst = &dstsock->sin6_addr; 332 333 #if 0 334 char ip[INET6_ADDRSTRLEN]; 335 336 if (dstsock->sin6_addr.s6_addr32[0] == 0 && 337 dstsock->sin6_addr.s6_addr32[1] == 0 && 338 !IN6_IS_ADDR_LOOPBACK(&dstsock->sin6_addr)) { 339 printf("in6_selectroute: strange destination %s\n", 340 inet_ntop(AF_INET6, &dstsock->sin6_addr, ip, sizeof(ip))); 341 } else { 342 printf("in6_selectroute: destination = %s%%%d\n", 343 inet_ntop(AF_INET6, &dstsock->sin6_addr, ip, sizeof(ip)), 344 dstsock->sin6_scope_id); /* for debug */ 345 } 346 #endif 347 348 /* If the caller specify the outgoing interface explicitly, use it. */ 349 if (opts && (pi = opts->ip6po_pktinfo) != NULL && pi->ipi6_ifindex) { 350 ifp = if_get(pi->ipi6_ifindex); 351 if (ifp != NULL && 352 (norouteok || retrt == NULL || 353 IN6_IS_ADDR_MULTICAST(dst))) { 354 /* 355 * we do not have to check or get the route for 356 * multicast. 357 */ 358 goto done; 359 } else 360 goto getroute; 361 } 362 363 /* 364 * If the destination address is a multicast address and the outgoing 365 * interface for the address is specified by the caller, use it. 366 */ 367 if (IN6_IS_ADDR_MULTICAST(dst) && 368 mopts != NULL && (ifp = mopts->im6o_multicast_ifp) != NULL) { 369 goto done; /* we do not need a route for multicast. */ 370 } 371 372 getroute: 373 /* 374 * If the next hop address for the packet is specified by the caller, 375 * use it as the gateway. 376 */ 377 if (opts && opts->ip6po_nexthop) { 378 struct route_in6 *ron; 379 380 sin6_next = satosin6(opts->ip6po_nexthop); 381 382 /* at this moment, we only support AF_INET6 next hops */ 383 if (sin6_next->sin6_family != AF_INET6) { 384 error = EAFNOSUPPORT; /* or should we proceed? */ 385 goto done; 386 } 387 388 /* 389 * If the next hop is an IPv6 address, then the node identified 390 * by that address must be a neighbor of the sending host. 391 */ 392 ron = &opts->ip6po_nextroute; 393 if ((ron->ro_rt && 394 (ron->ro_rt->rt_flags & (RTF_UP | RTF_GATEWAY)) != 395 RTF_UP) || 396 !IN6_ARE_ADDR_EQUAL(&ron->ro_dst.sin6_addr, 397 &sin6_next->sin6_addr)) { 398 if (ron->ro_rt) { 399 RTFREE(ron->ro_rt); 400 ron->ro_rt = NULL; 401 } 402 ron->ro_dst = *sin6_next; 403 ron->ro_tableid = rtableid; 404 } 405 if (ron->ro_rt == NULL) { 406 rtalloc((struct route *)ron); /* multi path case? */ 407 if (ron->ro_rt == NULL || 408 (ron->ro_rt->rt_flags & RTF_GATEWAY)) { 409 if (ron->ro_rt) { 410 RTFREE(ron->ro_rt); 411 ron->ro_rt = NULL; 412 } 413 error = EHOSTUNREACH; 414 goto done; 415 } 416 } 417 if (!nd6_is_addr_neighbor(sin6_next, ron->ro_rt->rt_ifp)) { 418 RTFREE(ron->ro_rt); 419 ron->ro_rt = NULL; 420 error = EHOSTUNREACH; 421 goto done; 422 } 423 rt = ron->ro_rt; 424 ifp = rt->rt_ifp; 425 426 /* 427 * When cloning is required, try to allocate a route to the 428 * destination so that the caller can store path MTU 429 * information. 430 */ 431 goto done; 432 } 433 434 /* 435 * Use a cached route if it exists and is valid, else try to allocate 436 * a new one. Note that we should check the address family of the 437 * cached destination, in case of sharing the cache with IPv4. 438 */ 439 if (ro) { 440 if (ro->ro_rt && 441 (!(ro->ro_rt->rt_flags & RTF_UP) || 442 sin6tosa(&ro->ro_dst)->sa_family != AF_INET6 || 443 !IN6_ARE_ADDR_EQUAL(&ro->ro_dst.sin6_addr, dst))) { 444 RTFREE(ro->ro_rt); 445 ro->ro_rt = (struct rtentry *)NULL; 446 } 447 if (ro->ro_rt == (struct rtentry *)NULL) { 448 struct sockaddr_in6 *sa6; 449 450 /* No route yet, so try to acquire one */ 451 bzero(&ro->ro_dst, sizeof(struct sockaddr_in6)); 452 ro->ro_tableid = rtableid; 453 sa6 = &ro->ro_dst; 454 *sa6 = *dstsock; 455 sa6->sin6_scope_id = 0; 456 ro->ro_tableid = rtableid; 457 rtalloc_mpath((struct route *)ro, NULL); 458 } 459 460 /* 461 * do not care about the result if we have the nexthop 462 * explicitly specified. 463 */ 464 if (opts && opts->ip6po_nexthop) 465 goto done; 466 467 if (ro->ro_rt) { 468 ifp = ro->ro_rt->rt_ifp; 469 470 if (ifp == NULL) { /* can this really happen? */ 471 RTFREE(ro->ro_rt); 472 ro->ro_rt = NULL; 473 } 474 } 475 if (ro->ro_rt == NULL) 476 error = EHOSTUNREACH; 477 rt = ro->ro_rt; 478 479 /* 480 * Check if the outgoing interface conflicts with 481 * the interface specified by ipi6_ifindex (if specified). 482 * Note that loopback interface is always okay. 483 * (this may happen when we are sending a packet to one of 484 * our own addresses.) 485 */ 486 if (opts && opts->ip6po_pktinfo && 487 opts->ip6po_pktinfo->ipi6_ifindex) { 488 if (!(ifp->if_flags & IFF_LOOPBACK) && 489 ifp->if_index != 490 opts->ip6po_pktinfo->ipi6_ifindex) { 491 error = EHOSTUNREACH; 492 goto done; 493 } 494 } 495 } 496 497 done: 498 if (ifp == NULL && rt == NULL) { 499 /* 500 * This can happen if the caller did not pass a cached route 501 * nor any other hints. We treat this case an error. 502 */ 503 error = EHOSTUNREACH; 504 } 505 if (error == EHOSTUNREACH) 506 ip6stat.ip6s_noroute++; 507 508 if (retifp != NULL) 509 *retifp = ifp; 510 if (retrt != NULL) 511 *retrt = rt; /* rt may be NULL */ 512 513 return (error); 514 } 515 516 int 517 in6_selectif(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, 518 struct ip6_moptions *mopts, struct route_in6 *ro, struct ifnet **retifp, 519 u_int rtableid) 520 { 521 struct rtentry *rt = NULL; 522 int error; 523 524 if ((error = selectroute(dstsock, opts, mopts, ro, retifp, 525 &rt, 1, rtableid)) != 0) 526 return (error); 527 528 /* 529 * do not use a rejected or black hole route. 530 * XXX: this check should be done in the L2 output routine. 531 * However, if we skipped this check here, we'd see the following 532 * scenario: 533 * - install a rejected route for a scoped address prefix 534 * (like fe80::/10) 535 * - send a packet to a destination that matches the scoped prefix, 536 * with ambiguity about the scope zone. 537 * - pick the outgoing interface from the route, and disambiguate the 538 * scope zone with the interface. 539 * - ip6_output() would try to get another route with the "new" 540 * destination, which may be valid. 541 * - we'd see no error on output. 542 * Although this may not be very harmful, it should still be confusing. 543 * We thus reject the case here. 544 */ 545 if (rt && (rt->rt_flags & (RTF_REJECT | RTF_BLACKHOLE))) 546 return (rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH); 547 548 /* 549 * Adjust the "outgoing" interface. If we're going to loop the packet 550 * back to ourselves, the ifp would be the loopback interface. 551 * However, we'd rather know the interface associated to the 552 * destination address (which should probably be one of our own 553 * addresses.) 554 */ 555 if (rt && rt->rt_ifa && rt->rt_ifa->ifa_ifp) 556 *retifp = rt->rt_ifa->ifa_ifp; 557 558 return (0); 559 } 560 561 int 562 in6_selectroute(struct sockaddr_in6 *dstsock, struct ip6_pktopts *opts, 563 struct ip6_moptions *mopts, struct route_in6 *ro, struct ifnet **retifp, 564 struct rtentry **retrt, u_int rtableid) 565 { 566 567 return (selectroute(dstsock, opts, mopts, ro, retifp, retrt, 0, 568 rtableid)); 569 } 570 571 /* 572 * Default hop limit selection. The precedence is as follows: 573 * 1. Hoplimit value specified via ioctl. 574 * 2. (If the outgoing interface is detected) the current 575 * hop limit of the interface specified by router advertisement. 576 * 3. The system default hoplimit. 577 */ 578 int 579 in6_selecthlim(struct inpcb *in6p, struct ifnet *ifp) 580 { 581 if (in6p && in6p->inp_hops >= 0) 582 return (in6p->inp_hops); 583 else if (ifp) 584 return (ND_IFINFO(ifp)->chlim); 585 else 586 return (ip6_defhlim); 587 } 588 589 /* 590 * generate kernel-internal form (scopeid embedded into s6_addr16[1]). 591 * If the address scope of is link-local, embed the interface index in the 592 * address. The routine determines our precedence 593 * between advanced API scope/interface specification and basic API 594 * specification. 595 * 596 * this function should be nuked in the future, when we get rid of 597 * embedded scopeid thing. 598 * 599 * XXX actually, it is over-specification to return ifp against sin6_scope_id. 600 * there can be multiple interfaces that belong to a particular scope zone 601 * (in specification, we have 1:N mapping between a scope zone and interfaces). 602 * we may want to change the function to return something other than ifp. 603 */ 604 int 605 in6_embedscope(struct in6_addr *in6, const struct sockaddr_in6 *sin6, 606 struct inpcb *in6p, struct ifnet **ifpp) 607 { 608 struct ifnet *ifp = NULL; 609 u_int32_t scopeid; 610 611 *in6 = sin6->sin6_addr; 612 scopeid = sin6->sin6_scope_id; 613 if (ifpp) 614 *ifpp = NULL; 615 616 /* 617 * don't try to read sin6->sin6_addr beyond here, since the caller may 618 * ask us to overwrite existing sockaddr_in6 619 */ 620 621 if (IN6_IS_SCOPE_EMBED(in6)) { 622 struct in6_pktinfo *pi; 623 624 /* 625 * KAME assumption: link id == interface id 626 */ 627 628 if (in6p && in6p->inp_outputopts6 && 629 (pi = in6p->inp_outputopts6->ip6po_pktinfo) && 630 pi->ipi6_ifindex) { 631 ifp = if_get(pi->ipi6_ifindex); 632 if (ifp == NULL) 633 return ENXIO; /* XXX EINVAL? */ 634 in6->s6_addr16[1] = htons(pi->ipi6_ifindex); 635 } else if (in6p && IN6_IS_ADDR_MULTICAST(in6) && 636 in6p->inp_moptions6 && 637 in6p->inp_moptions6->im6o_multicast_ifp) { 638 ifp = in6p->inp_moptions6->im6o_multicast_ifp; 639 in6->s6_addr16[1] = htons(ifp->if_index); 640 } else if (scopeid) { 641 ifp = if_get(scopeid); 642 if (ifp == NULL) 643 return ENXIO; /* XXX EINVAL? */ 644 /*XXX assignment to 16bit from 32bit variable */ 645 in6->s6_addr16[1] = htons(scopeid & 0xffff); 646 } 647 648 if (ifpp) 649 *ifpp = ifp; 650 } 651 652 return 0; 653 } 654 655 /* 656 * generate standard sockaddr_in6 from embedded form. 657 * touches sin6_addr and sin6_scope_id only. 658 * 659 * this function should be nuked in the future, when we get rid of 660 * embedded scopeid thing. 661 */ 662 int 663 in6_recoverscope(struct sockaddr_in6 *sin6, const struct in6_addr *in6, 664 struct ifnet *ifp) 665 { 666 u_int32_t scopeid; 667 668 sin6->sin6_addr = *in6; 669 670 /* 671 * don't try to read *in6 beyond here, since the caller may 672 * ask us to overwrite existing sockaddr_in6 673 */ 674 675 sin6->sin6_scope_id = 0; 676 if (IN6_IS_SCOPE_EMBED(in6)) { 677 /* 678 * KAME assumption: link id == interface id 679 */ 680 scopeid = ntohs(sin6->sin6_addr.s6_addr16[1]); 681 if (scopeid) { 682 /* sanity check */ 683 if (if_get(scopeid) == NULL) 684 return ENXIO; 685 if (ifp && ifp->if_index != scopeid) 686 return ENXIO; 687 sin6->sin6_addr.s6_addr16[1] = 0; 688 sin6->sin6_scope_id = scopeid; 689 } 690 } 691 692 return 0; 693 } 694 695 /* 696 * just clear the embedded scope identifer. 697 */ 698 void 699 in6_clearscope(struct in6_addr *addr) 700 { 701 if (IN6_IS_SCOPE_EMBED(addr)) 702 addr->s6_addr16[1] = 0; 703 } 704