in6_ifattach.c revision 1.40
1/* $OpenBSD: in6_ifattach.c,v 1.40 2006/03/05 21:48:57 miod Exp $ */ 2/* $KAME: in6_ifattach.c,v 1.124 2001/07/18 08:32:51 jinmei 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#include <sys/param.h> 34#include <sys/systm.h> 35#include <sys/malloc.h> 36#include <sys/socket.h> 37#include <sys/sockio.h> 38#include <sys/kernel.h> 39#include <sys/syslog.h> 40 41#include <crypto/md5.h> 42 43#include <net/if.h> 44#include <net/if_dl.h> 45#include <net/if_types.h> 46#include <net/route.h> 47 48#include <netinet/in.h> 49#include <netinet/in_var.h> 50#include <netinet/if_ether.h> 51 52#include <netinet/ip6.h> 53#include <netinet6/ip6_var.h> 54#include <netinet6/in6_ifattach.h> 55#include <netinet6/ip6_var.h> 56#include <netinet6/nd6.h> 57#include <netinet6/ip6_mroute.h> 58 59unsigned long in6_maxmtu = 0; 60 61int ip6_auto_linklocal = 1; /* enable by default */ 62 63static int get_rand_ifid(struct ifnet *, struct in6_addr *); 64static int get_hw_ifid(struct ifnet *, struct in6_addr *); 65static int get_ifid(struct ifnet *, struct ifnet *, struct in6_addr *); 66static int in6_ifattach_linklocal(struct ifnet *, struct ifnet *); 67static int in6_ifattach_loopback(struct ifnet *); 68 69#define EUI64_GBIT 0x01 70#define EUI64_UBIT 0x02 71#define EUI64_TO_IFID(in6) do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (0) 72#define EUI64_GROUP(in6) ((in6)->s6_addr[8] & EUI64_GBIT) 73#define EUI64_INDIVIDUAL(in6) (!EUI64_GROUP(in6)) 74#define EUI64_LOCAL(in6) ((in6)->s6_addr[8] & EUI64_UBIT) 75#define EUI64_UNIVERSAL(in6) (!EUI64_LOCAL(in6)) 76 77#define IFID_LOCAL(in6) (!EUI64_LOCAL(in6)) 78#define IFID_UNIVERSAL(in6) (!EUI64_UNIVERSAL(in6)) 79 80/* 81 * Generate a last-resort interface identifier, when the machine has no 82 * IEEE802/EUI64 address sources. 83 * The goal here is to get an interface identifier that is 84 * (1) random enough and (2) does not change across reboot. 85 * We currently use MD5(hostname) for it. 86 */ 87static int 88get_rand_ifid(ifp, in6) 89 struct ifnet *ifp; 90 struct in6_addr *in6; /* upper 64bits are preserved */ 91{ 92 MD5_CTX ctxt; 93 u_int8_t digest[16]; 94 95#if 0 96 /* we need at least several letters as seed for ifid */ 97 if (hostnamelen < 3) 98 return -1; 99#endif 100 101 /* generate 8 bytes of pseudo-random value. */ 102 bzero(&ctxt, sizeof(ctxt)); 103 MD5Init(&ctxt); 104 MD5Update(&ctxt, hostname, hostnamelen); 105 MD5Final(digest, &ctxt); 106 107 /* assumes sizeof(digest) > sizeof(ifid) */ 108 bcopy(digest, &in6->s6_addr[8], 8); 109 110 /* make sure to set "u" bit to local, and "g" bit to individual. */ 111 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 112 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 113 114 /* convert EUI64 into IPv6 interface identifier */ 115 EUI64_TO_IFID(in6); 116 117 return 0; 118} 119 120/* 121 * Get interface identifier for the specified interface. 122 * XXX assumes single sockaddr_dl (AF_LINK address) per an interface 123 */ 124static int 125get_hw_ifid(ifp, in6) 126 struct ifnet *ifp; 127 struct in6_addr *in6; /* upper 64bits are preserved */ 128{ 129 struct ifaddr *ifa; 130 struct sockaddr_dl *sdl; 131 char *addr; 132 size_t addrlen; 133 static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; 134 static u_int8_t allone[8] = 135 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 136 137 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 138 if (ifa->ifa_addr->sa_family != AF_LINK) 139 continue; 140 sdl = (struct sockaddr_dl *)ifa->ifa_addr; 141 if (sdl == NULL) 142 continue; 143 if (sdl->sdl_alen == 0) 144 continue; 145 146 goto found; 147 } 148 149 return -1; 150 151found: 152 addr = LLADDR(sdl); 153 addrlen = sdl->sdl_alen; 154 155 switch (ifp->if_type) { 156 case IFT_IEEE1394: 157 case IFT_IEEE80211: 158 /* IEEE1394 uses 16byte length address starting with EUI64 */ 159 if (addrlen > 8) 160 addrlen = 8; 161 break; 162 default: 163 break; 164 } 165 166 /* get EUI64 */ 167 switch (ifp->if_type) { 168 /* IEEE802/EUI64 cases - what others? */ 169 case IFT_ETHER: 170 case IFT_FDDI: 171 case IFT_ATM: 172 case IFT_IEEE1394: 173 case IFT_IEEE80211: 174 /* look at IEEE802/EUI64 only */ 175 if (addrlen != 8 && addrlen != 6) 176 return -1; 177 178 /* 179 * check for invalid MAC address - on bsdi, we see it a lot 180 * since wildboar configures all-zero MAC on pccard before 181 * card insertion. 182 */ 183 if (bcmp(addr, allzero, addrlen) == 0) 184 return -1; 185 if (bcmp(addr, allone, addrlen) == 0) 186 return -1; 187 188 /* make EUI64 address */ 189 if (addrlen == 8) 190 bcopy(addr, &in6->s6_addr[8], 8); 191 else if (addrlen == 6) { 192 in6->s6_addr[8] = addr[0]; 193 in6->s6_addr[9] = addr[1]; 194 in6->s6_addr[10] = addr[2]; 195 in6->s6_addr[11] = 0xff; 196 in6->s6_addr[12] = 0xfe; 197 in6->s6_addr[13] = addr[3]; 198 in6->s6_addr[14] = addr[4]; 199 in6->s6_addr[15] = addr[5]; 200 } 201 break; 202 203 case IFT_ARCNET: 204 if (addrlen != 1) 205 return -1; 206 if (!addr[0]) 207 return -1; 208 209 bzero(&in6->s6_addr[8], 8); 210 in6->s6_addr[15] = addr[0]; 211 212 /* 213 * due to insufficient bitwidth, we mark it local. 214 */ 215 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 216 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 217 break; 218 219 case IFT_GIF: 220 /* 221 * RFC2893 says: "SHOULD use IPv4 address as ifid source". 222 * however, IPv4 address is not very suitable as unique 223 * identifier source (can be renumbered). 224 * we don't do this. 225 */ 226 return -1; 227 228 default: 229 return -1; 230 } 231 232 /* sanity check: g bit must not indicate "group" */ 233 if (EUI64_GROUP(in6)) 234 return -1; 235 236 /* convert EUI64 into IPv6 interface identifier */ 237 EUI64_TO_IFID(in6); 238 239 /* 240 * sanity check: ifid must not be all zero, avoid conflict with 241 * subnet router anycast 242 */ 243 if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 && 244 bcmp(&in6->s6_addr[9], allzero, 7) == 0) { 245 return -1; 246 } 247 248 return 0; 249} 250 251/* 252 * Get interface identifier for the specified interface. If it is not 253 * available on ifp0, borrow interface identifier from other information 254 * sources. 255 */ 256static int 257get_ifid(ifp0, altifp, in6) 258 struct ifnet *ifp0; 259 struct ifnet *altifp; /* secondary EUI64 source */ 260 struct in6_addr *in6; 261{ 262 struct ifnet *ifp; 263 264 /* first, try to get it from the interface itself */ 265 if (get_hw_ifid(ifp0, in6) == 0) { 266 nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n", 267 ifp0->if_xname)); 268 goto success; 269 } 270 271 /* try secondary EUI64 source. this basically is for ATM PVC */ 272 if (altifp && get_hw_ifid(altifp, in6) == 0) { 273 nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n", 274 ifp0->if_xname, altifp->if_xname)); 275 goto success; 276 } 277 278 /* next, try to get it from some other hardware interface */ 279 TAILQ_FOREACH(ifp, &ifnet, if_list) { 280 if (ifp == ifp0) 281 continue; 282 if (get_hw_ifid(ifp, in6) != 0) 283 continue; 284 285 /* 286 * to borrow ifid from other interface, ifid needs to be 287 * globally unique 288 */ 289 if (IFID_UNIVERSAL(in6)) { 290 nd6log((LOG_DEBUG, 291 "%s: borrow interface identifier from %s\n", 292 ifp0->if_xname, ifp->if_xname)); 293 goto success; 294 } 295 } 296 297 /* last resort: get from random number source */ 298 if (get_rand_ifid(ifp, in6) == 0) { 299 nd6log((LOG_DEBUG, 300 "%s: interface identifier generated by random number\n", 301 ifp0->if_xname)); 302 goto success; 303 } 304 305 printf("%s: failed to get interface identifier\n", ifp0->if_xname); 306 return -1; 307 308success: 309 nd6log((LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n", 310 ifp0->if_xname, in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10], 311 in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13], 312 in6->s6_addr[14], in6->s6_addr[15])); 313 return 0; 314} 315 316static int 317in6_ifattach_linklocal(ifp, altifp) 318 struct ifnet *ifp; 319 struct ifnet *altifp; /*secondary EUI64 source*/ 320{ 321 struct in6_ifaddr *ia; 322 struct in6_aliasreq ifra; 323 struct nd_prefix pr0; 324 int i, error; 325 326 /* 327 * configure link-local address. 328 */ 329 bzero(&ifra, sizeof(ifra)); 330 331 /* 332 * in6_update_ifa() does not use ifra_name, but we accurately set it 333 * for safety. 334 */ 335 strncpy(ifra.ifra_name, ifp->if_xname, sizeof(ifra.ifra_name)); 336 337 ifra.ifra_addr.sin6_family = AF_INET6; 338 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); 339 ifra.ifra_addr.sin6_addr.s6_addr16[0] = htons(0xfe80); 340 ifra.ifra_addr.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 341 ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0; 342 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 343 ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0; 344 ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1); 345 } else { 346 if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) { 347 nd6log((LOG_ERR, 348 "%s: no ifid available\n", ifp->if_xname)); 349 return (-1); 350 } 351 } 352 353 ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6); 354 ifra.ifra_prefixmask.sin6_family = AF_INET6; 355 ifra.ifra_prefixmask.sin6_addr = in6mask64; 356#ifdef SCOPEDROUTING 357 /* take into account the sin6_scope_id field for routing */ 358 ifra.ifra_prefixmask.sin6_scope_id = 0xffffffff; 359#endif 360 /* link-local addresses should NEVER expire. */ 361 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 362 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 363 364 /* 365 * Do not let in6_update_ifa() do DAD, since we need a random delay 366 * before sending an NS at the first time the interface becomes up. 367 * Instead, in6_if_up() will start DAD with a proper random delay. 368 */ 369 ifra.ifra_flags |= IN6_IFF_NODAD; 370 371 /* 372 * Now call in6_update_ifa() to do a bunch of procedures to configure 373 * a link-local address. We can set NULL to the 3rd argument, because 374 * we know there's no other link-local address on the interface 375 * and therefore we are adding one (instead of updating one). 376 */ 377 if ((error = in6_update_ifa(ifp, &ifra, NULL)) != 0) { 378 /* 379 * XXX: When the interface does not support IPv6, this call 380 * would fail in the SIOCSIFADDR ioctl. I believe the 381 * notification is rather confusing in this case, so just 382 * suppress it. (jinmei@kame.net 20010130) 383 */ 384 if (error != EAFNOSUPPORT) 385 nd6log((LOG_NOTICE, "in6_ifattach_linklocal: failed to " 386 "configure a link-local address on %s " 387 "(errno=%d)\n", 388 ifp->if_xname, error)); 389 return (-1); 390 } 391 392 /* 393 * Adjust ia6_flags so that in6_if_up will perform DAD. 394 * XXX: Some P2P interfaces seem not to send packets just after 395 * becoming up, so we skip p2p interfaces for safety. 396 */ 397 ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */ 398#ifdef DIAGNOSTIC 399 if (!ia) { 400 panic("ia == NULL in in6_ifattach_linklocal"); 401 /* NOTREACHED */ 402 } 403#endif 404 if (in6if_do_dad(ifp) && (ifp->if_flags & IFF_POINTOPOINT) == 0) { 405 ia->ia6_flags &= ~IN6_IFF_NODAD; 406 ia->ia6_flags |= IN6_IFF_TENTATIVE; 407 } 408 409 /* 410 * Make the link-local prefix (fe80::/64%link) as on-link. 411 * Since we'd like to manage prefixes separately from addresses, 412 * we make an ND6 prefix structure for the link-local prefix, 413 * and add it to the prefix list as a never-expire prefix. 414 * XXX: this change might affect some existing code base... 415 */ 416 bzero(&pr0, sizeof(pr0)); 417 pr0.ndpr_ifp = ifp; 418 /* this should be 64 at this moment. */ 419 pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL); 420 pr0.ndpr_mask = ifra.ifra_prefixmask.sin6_addr; 421 pr0.ndpr_prefix = ifra.ifra_addr; 422 /* apply the mask for safety. (nd6_prelist_add will apply it again) */ 423 for (i = 0; i < 4; i++) { 424 pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &= 425 in6mask64.s6_addr32[i]; 426 } 427 /* 428 * Initialize parameters. The link-local prefix must always be 429 * on-link, and its lifetimes never expire. 430 */ 431 pr0.ndpr_raf_onlink = 1; 432 pr0.ndpr_raf_auto = 1; /* probably meaningless */ 433 pr0.ndpr_vltime = ND6_INFINITE_LIFETIME; 434 pr0.ndpr_pltime = ND6_INFINITE_LIFETIME; 435 /* 436 * Since there is no other link-local addresses, nd6_prefix_lookup() 437 * probably returns NULL. However, we cannot always expect the result. 438 * For example, if we first remove the (only) existing link-local 439 * address, and then reconfigure another one, the prefix is still 440 * valid with referring to the old link-local address. 441 */ 442 if (nd6_prefix_lookup(&pr0) == NULL) { 443 if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0) 444 return (error); 445 } 446 447 return 0; 448} 449 450static int 451in6_ifattach_loopback(ifp) 452 struct ifnet *ifp; /* must be IFT_LOOP */ 453{ 454 struct in6_aliasreq ifra; 455 int error; 456 457 bzero(&ifra, sizeof(ifra)); 458 459 /* 460 * in6_update_ifa() does not use ifra_name, but we accurately set it 461 * for safety. 462 */ 463 strncpy(ifra.ifra_name, ifp->if_xname, sizeof(ifra.ifra_name)); 464 465 ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6); 466 ifra.ifra_prefixmask.sin6_family = AF_INET6; 467 ifra.ifra_prefixmask.sin6_addr = in6mask128; 468 469 /* 470 * Always initialize ia_dstaddr (= broadcast address) to loopback 471 * address. Follows IPv4 practice - see in_ifinit(). 472 */ 473 ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6); 474 ifra.ifra_dstaddr.sin6_family = AF_INET6; 475 ifra.ifra_dstaddr.sin6_addr = in6addr_loopback; 476 477 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); 478 ifra.ifra_addr.sin6_family = AF_INET6; 479 ifra.ifra_addr.sin6_addr = in6addr_loopback; 480 481 /* the loopback address should NEVER expire. */ 482 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 483 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 484 485 /* we don't need to perform DAD on loopback interfaces. */ 486 ifra.ifra_flags |= IN6_IFF_NODAD; 487 488 /* 489 * We are sure that this is a newly assigned address, so we can set 490 * NULL to the 3rd arg. 491 */ 492 if ((error = in6_update_ifa(ifp, &ifra, NULL)) != 0) { 493 nd6log((LOG_ERR, "in6_ifattach_loopback: failed to configure " 494 "the loopback address on %s (errno=%d)\n", 495 ifp->if_xname, error)); 496 return (-1); 497 } 498 499 return 0; 500} 501 502/* 503 * compute NI group address, based on the current hostname setting. 504 * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later). 505 * 506 * when ifp == NULL, the caller is responsible for filling scopeid. 507 */ 508int 509in6_nigroup(ifp, name, namelen, sa6) 510 struct ifnet *ifp; 511 const char *name; 512 int namelen; 513 struct sockaddr_in6 *sa6; 514{ 515 const char *p; 516 u_int8_t *q; 517 MD5_CTX ctxt; 518 u_int8_t digest[16]; 519 u_int8_t l; 520 u_int8_t n[64]; /* a single label must not exceed 63 chars */ 521 522 if (!namelen || !name) 523 return -1; 524 525 p = name; 526 while (p && *p && *p != '.' && p - name < namelen) 527 p++; 528 if (p - name > sizeof(n) - 1) 529 return -1; /* label too long */ 530 l = p - name; 531 strncpy((char *)n, name, l); 532 n[(int)l] = '\0'; 533 for (q = n; *q; q++) { 534 if ('A' <= *q && *q <= 'Z') 535 *q = *q - 'A' + 'a'; 536 } 537 538 /* generate 8 bytes of pseudo-random value. */ 539 bzero(&ctxt, sizeof(ctxt)); 540 MD5Init(&ctxt); 541 MD5Update(&ctxt, &l, sizeof(l)); 542 MD5Update(&ctxt, n, l); 543 MD5Final(digest, &ctxt); 544 545 bzero(sa6, sizeof(*sa6)); 546 sa6->sin6_family = AF_INET6; 547 sa6->sin6_len = sizeof(*sa6); 548 sa6->sin6_addr.s6_addr16[0] = htons(0xff02); 549 sa6->sin6_addr.s6_addr16[1] = htons(ifp->if_index); 550 sa6->sin6_addr.s6_addr8[11] = 2; 551 bcopy(digest, &sa6->sin6_addr.s6_addr32[3], 552 sizeof(sa6->sin6_addr.s6_addr32[3])); 553 554 return 0; 555} 556 557/* 558 * XXX multiple loopback interface needs more care. for instance, 559 * nodelocal address needs to be configured onto only one of them. 560 * XXX multiple link-local address case 561 */ 562void 563in6_ifattach(ifp, altifp) 564 struct ifnet *ifp; 565 struct ifnet *altifp; /* secondary EUI64 source */ 566{ 567 struct in6_ifaddr *ia; 568 struct in6_addr in6; 569 570 /* some of the interfaces are inherently not IPv6 capable */ 571 switch (ifp->if_type) { 572 case IFT_BRIDGE: 573 case IFT_ENC: 574 case IFT_PFLOG: 575 case IFT_PFSYNC: 576 return; 577 } 578 579 /* 580 * if link mtu is too small, don't try to configure IPv6. 581 * remember there could be some link-layer that has special 582 * fragmentation logic. 583 */ 584 if (ifp->if_mtu < IPV6_MMTU) { 585 nd6log((LOG_INFO, "in6_ifattach: " 586 "%s has too small MTU, IPv6 not enabled\n", 587 ifp->if_xname)); 588 return; 589 } 590 591 /* create a multicast kludge storage (if we have not had one) */ 592 in6_createmkludge(ifp); 593 594 /* 595 * quirks based on interface type 596 */ 597 switch (ifp->if_type) { 598 case IFT_CARP: 599 return; 600 default: 601 break; 602 } 603 604 /* 605 * usually, we require multicast capability to the interface 606 */ 607 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 608 nd6log((LOG_INFO, "in6_ifattach: " 609 "%s is not multicast capable, IPv6 not enabled\n", 610 ifp->if_xname)); 611 return; 612 } 613 614 /* 615 * assign loopback address for loopback interface. 616 * XXX multiple loopback interface case. 617 */ 618 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 619 in6 = in6addr_loopback; 620 if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) { 621 if (in6_ifattach_loopback(ifp) != 0) 622 return; 623 } 624 } 625 626 /* 627 * assign a link-local address, if there's none. 628 */ 629 if (ip6_auto_linklocal) { 630 ia = in6ifa_ifpforlinklocal(ifp, 0); 631 if (ia == NULL) { 632 if (in6_ifattach_linklocal(ifp, altifp) == 0) { 633 /* linklocal address assigned */ 634 } else { 635 /* failed to assign linklocal address. bark? */ 636 } 637 } 638 } 639} 640 641/* 642 * NOTE: in6_ifdetach() does not support loopback if at this moment. 643 */ 644void 645in6_ifdetach(ifp) 646 struct ifnet *ifp; 647{ 648 struct in6_ifaddr *ia, *oia; 649 struct ifaddr *ifa, *next; 650 struct rtentry *rt; 651 short rtflags; 652 struct sockaddr_in6 sin6; 653 struct in6_multi_mship *imm; 654 655 /* remove ip6_mrouter stuff */ 656 ip6_mrouter_detach(ifp); 657 658 /* remove neighbor management table */ 659 nd6_purge(ifp); 660 661 /* nuke any of IPv6 addresses we have */ 662 for (ifa = TAILQ_FIRST(&ifp->if_addrlist); 663 ifa != TAILQ_END(&ifp->if_addrlist); ifa = next) { 664 next = TAILQ_NEXT(ifa, ifa_list); 665 if (ifa->ifa_addr->sa_family != AF_INET6) 666 continue; 667 in6_purgeaddr(ifa); 668 } 669 670 /* undo everything done by in6_ifattach(), just in case */ 671 for (ifa = TAILQ_FIRST(&ifp->if_addrlist); 672 ifa != TAILQ_END(&ifp->if_addrlist); ifa = next) { 673 next = TAILQ_NEXT(ifa, ifa_list); 674 675 if (ifa->ifa_addr->sa_family != AF_INET6 676 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) { 677 continue; 678 } 679 680 ia = (struct in6_ifaddr *)ifa; 681 682 /* 683 * leave from multicast groups we have joined for the interface 684 */ 685 while (!LIST_EMPTY(&ia->ia6_memberships)) { 686 imm = LIST_FIRST(&ia->ia6_memberships); 687 LIST_REMOVE(imm, i6mm_chain); 688 in6_leavegroup(imm); 689 } 690 691 /* remove from the routing table */ 692 if ((ia->ia_flags & IFA_ROUTE) && 693 (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0))) { 694 rtflags = rt->rt_flags; 695 rtfree(rt); 696 rtrequest(RTM_DELETE, (struct sockaddr *)&ia->ia_addr, 697 (struct sockaddr *)&ia->ia_addr, 698 (struct sockaddr *)&ia->ia_prefixmask, 699 rtflags, (struct rtentry **)0); 700 } 701 702 /* remove from the linked list */ 703 TAILQ_REMOVE(&ifp->if_addrlist, (struct ifaddr *)ia, ifa_list); 704 IFAFREE(&ia->ia_ifa); 705 706 /* also remove from the IPv6 address chain(itojun&jinmei) */ 707 oia = ia; 708 if (oia == (ia = in6_ifaddr)) 709 in6_ifaddr = ia->ia_next; 710 else { 711 while (ia->ia_next && (ia->ia_next != oia)) 712 ia = ia->ia_next; 713 if (ia->ia_next) 714 ia->ia_next = oia->ia_next; 715 else { 716 nd6log((LOG_ERR, 717 "%s: didn't unlink in6ifaddr from list\n", 718 ifp->if_xname)); 719 } 720 } 721 722 IFAFREE(&oia->ia_ifa); 723 } 724 725 /* cleanup multicast address kludge table, if there is any */ 726 in6_purgemkludge(ifp); 727 728 /* 729 * remove neighbor management table. we call it twice just to make 730 * sure we nuke everything. maybe we need just one call. 731 * XXX: since the first call did not release addresses, some prefixes 732 * might remain. We should call nd6_purge() again to release the 733 * prefixes after removing all addresses above. 734 * (Or can we just delay calling nd6_purge until at this point?) 735 */ 736 nd6_purge(ifp); 737 738 /* remove route to link-local allnodes multicast (ff02::1) */ 739 bzero(&sin6, sizeof(sin6)); 740 sin6.sin6_len = sizeof(struct sockaddr_in6); 741 sin6.sin6_family = AF_INET6; 742 sin6.sin6_addr = in6addr_linklocal_allnodes; 743 sin6.sin6_addr.s6_addr16[1] = htons(ifp->if_index); 744 rt = rtalloc1((struct sockaddr *)&sin6, 0); 745 if (rt && rt->rt_ifp == ifp) { 746 rtrequest(RTM_DELETE, (struct sockaddr *)rt_key(rt), 747 rt->rt_gateway, rt_mask(rt), rt->rt_flags, 0); 748 rtfree(rt); 749 } 750} 751