1 /* $NetBSD: in6_ifattach.c,v 1.79 2007/12/06 00:28:36 dyoung 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/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: in6_ifattach.c,v 1.79 2007/12/06 00:28:36 dyoung Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/malloc.h> 39 #include <sys/socket.h> 40 #include <sys/sockio.h> 41 #include <sys/kernel.h> 42 #include <sys/syslog.h> 43 #include <sys/md5.h> 44 45 #include <net/if.h> 46 #include <net/if_dl.h> 47 #include <net/if_types.h> 48 #include <net/route.h> 49 50 #include <netinet/in.h> 51 #include <netinet/in_var.h> 52 53 #include <netinet/ip6.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 #include <netinet6/scope6_var.h> 59 60 #include <net/net_osdep.h> 61 62 unsigned long in6_maxmtu = 0; 63 64 int ip6_auto_linklocal = 1; /* enable by default */ 65 66 callout_t in6_tmpaddrtimer_ch; 67 68 69 #if 0 70 static int get_hostid_ifid(struct ifnet *, struct in6_addr *); 71 #endif 72 static int get_rand_ifid(struct ifnet *, struct in6_addr *); 73 static int generate_tmp_ifid(u_int8_t *, const u_int8_t *, u_int8_t *); 74 static int get_ifid(struct ifnet *, struct ifnet *, struct in6_addr *); 75 static int in6_ifattach_linklocal(struct ifnet *, struct ifnet *); 76 static int in6_ifattach_loopback(struct ifnet *); 77 78 #define EUI64_GBIT 0x01 79 #define EUI64_UBIT 0x02 80 #define EUI64_TO_IFID(in6) do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (/*CONSTCOND*/ 0) 81 #define EUI64_GROUP(in6) ((in6)->s6_addr[8] & EUI64_GBIT) 82 #define EUI64_INDIVIDUAL(in6) (!EUI64_GROUP(in6)) 83 #define EUI64_LOCAL(in6) ((in6)->s6_addr[8] & EUI64_UBIT) 84 #define EUI64_UNIVERSAL(in6) (!EUI64_LOCAL(in6)) 85 86 #define IFID_LOCAL(in6) (!EUI64_LOCAL(in6)) 87 #define IFID_UNIVERSAL(in6) (!EUI64_UNIVERSAL(in6)) 88 89 #define GEN_TEMPID_RETRY_MAX 5 90 91 #if 0 92 /* 93 * Generate a last-resort interface identifier from hostid. 94 * works only for certain architectures (like sparc). 95 * also, using hostid itself may constitute a privacy threat, much worse 96 * than MAC addresses (hostids are used for software licensing). 97 * maybe we should use MD5(hostid) instead. 98 * 99 * in6 - upper 64bits are preserved 100 */ 101 static int 102 get_hostid_ifid(struct ifnet *ifp, struct in6_addr *in6) 103 { 104 int off, len; 105 static const uint8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; 106 static const uint8_t allone[8] = 107 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 108 109 if (!hostid) 110 return -1; 111 112 /* get up to 8 bytes from the hostid field - should we get */ 113 len = (sizeof(hostid) > 8) ? 8 : sizeof(hostid); 114 off = sizeof(*in6) - len; 115 memcpy(&in6->s6_addr[off], &hostid, len); 116 117 /* make sure we do not return anything bogus */ 118 if (memcmp(&in6->s6_addr[8], allzero, sizeof(allzero))) 119 return -1; 120 if (memcmp(&in6->s6_addr[8], allone, sizeof(allone))) 121 return -1; 122 123 /* make sure to set "u" bit to local, and "g" bit to individual. */ 124 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 125 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 126 127 /* convert EUI64 into IPv6 interface identifier */ 128 EUI64_TO_IFID(in6); 129 130 return 0; 131 } 132 #endif 133 134 /* 135 * Generate a last-resort interface identifier, when the machine has no 136 * IEEE802/EUI64 address sources. 137 * The goal here is to get an interface identifier that is 138 * (1) random enough and (2) does not change across reboot. 139 * We currently use MD5(hostname) for it. 140 */ 141 static int 142 get_rand_ifid(struct ifnet *ifp, 143 struct in6_addr *in6) /* upper 64bits are preserved */ 144 { 145 MD5_CTX ctxt; 146 u_int8_t digest[16]; 147 148 #if 0 149 /* we need at least several letters as seed for ifid */ 150 if (hostnamelen < 3) 151 return -1; 152 #endif 153 154 /* generate 8 bytes of pseudo-random value. */ 155 memset(&ctxt, 0, sizeof(ctxt)); 156 MD5Init(&ctxt); 157 MD5Update(&ctxt, (u_char *)hostname, hostnamelen); 158 MD5Final(digest, &ctxt); 159 160 /* assumes sizeof(digest) > sizeof(ifid) */ 161 memcpy(&in6->s6_addr[8], digest, 8); 162 163 /* make sure to set "u" bit to local, and "g" bit to individual. */ 164 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 165 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 166 167 /* convert EUI64 into IPv6 interface identifier */ 168 EUI64_TO_IFID(in6); 169 170 return 0; 171 } 172 173 static int 174 generate_tmp_ifid(u_int8_t *seed0, const u_int8_t *seed1, u_int8_t *ret) 175 { 176 MD5_CTX ctxt; 177 u_int8_t seed[16], digest[16], nullbuf[8]; 178 u_int32_t val32; 179 /* 180 * interface ID for subnet anycast addresses. 181 * XXX: we assume the unicast address range that requires IDs 182 * in EUI-64 format. 183 */ 184 static const uint8_t anycast_id[8] = { 0xfd, 0xff, 0xff, 0xff, 185 0xff, 0xff, 0xff, 0x80 }; 186 static const uint8_t isatap_id[4] = { 0x00, 0x00, 0x5e, 0xfe }; 187 int badid, retry = 0; 188 189 /* If there's no hisotry, start with a random seed. */ 190 memset(nullbuf, 0, sizeof(nullbuf)); 191 if (memcmp(nullbuf, seed0, sizeof(nullbuf)) == 0) { 192 int i; 193 194 for (i = 0; i < 2; i++) { 195 val32 = arc4random(); 196 memcpy(seed + sizeof(val32) * i, &val32, sizeof(val32)); 197 } 198 } else 199 memcpy(seed, seed0, 8); 200 201 /* copy the right-most 64-bits of the given address */ 202 /* XXX assumption on the size of IFID */ 203 memcpy(&seed[8], seed1, 8); 204 205 again: 206 /* for debugging purposes only */ 207 #if 0 208 { 209 int i; 210 211 printf("generate_tmp_ifid: new randomized ID from: "); 212 for (i = 0; i < 16; i++) 213 printf("%02x", seed[i]); 214 printf(" "); 215 } 216 #endif 217 218 /* generate 16 bytes of pseudo-random value. */ 219 memset(&ctxt, 0, sizeof(ctxt)); 220 MD5Init(&ctxt); 221 MD5Update(&ctxt, seed, sizeof(seed)); 222 MD5Final(digest, &ctxt); 223 224 /* 225 * draft-ietf-ipngwg-temp-addresses-v2-00.txt 3.2.1. (3) 226 * Take the left-most 64-bits of the MD5 digest and set bit 6 (the 227 * left-most bit is numbered 0) to zero. 228 */ 229 memcpy(ret, digest, 8); 230 ret[0] &= ~EUI64_UBIT; 231 232 /* 233 * Reject inappropriate identifiers according to 234 * draft-ietf-ipngwg-temp-addresses-v2-00.txt 3.2.1. (4) 235 * At this moment, we reject following cases: 236 * - all 0 identifier 237 * - identifiers that conflict with reserved subnet anycast addresses, 238 * which are defined in RFC 2526. 239 * - identifiers that conflict with ISATAP addresses 240 * - identifiers used in our own addresses 241 */ 242 badid = 0; 243 if (memcmp(nullbuf, ret, sizeof(nullbuf)) == 0) 244 badid = 1; 245 else if (memcmp(anycast_id, ret, 7) == 0 && 246 (anycast_id[7] & ret[7]) == anycast_id[7]) { 247 badid = 1; 248 } else if (memcmp(isatap_id, ret, sizeof(isatap_id)) == 0) 249 badid = 1; 250 else { 251 struct in6_ifaddr *ia; 252 253 for (ia = in6_ifaddr; ia; ia = ia->ia_next) { 254 if (!memcmp(&ia->ia_addr.sin6_addr.s6_addr[8], 255 ret, 8)) { 256 badid = 1; 257 break; 258 } 259 } 260 } 261 262 /* 263 * In the event that an unacceptable identifier has been generated, 264 * restart the process, using the right-most 64 bits of the MD5 digest 265 * obtained in place of the history value. 266 */ 267 if (badid) { 268 /* for debugging purposes only */ 269 #if 0 270 { 271 int i; 272 273 printf("unacceptable random ID: "); 274 for (i = 0; i < 16; i++) 275 printf("%02x", digest[i]); 276 printf("\n"); 277 } 278 #endif 279 280 if (++retry < GEN_TEMPID_RETRY_MAX) { 281 memcpy(seed, &digest[8], 8); 282 goto again; 283 } else { 284 /* 285 * We're so unlucky. Give up for now, and return 286 * all 0 IDs to tell the caller not to make a 287 * temporary address. 288 */ 289 nd6log((LOG_NOTICE, 290 "generate_tmp_ifid: never found a good ID\n")); 291 memset(ret, 0, 8); 292 } 293 } 294 295 /* 296 * draft-ietf-ipngwg-temp-addresses-v2-00.txt 3.2.1. (6) 297 * Take the rightmost 64-bits of the MD5 digest and save them in 298 * stable storage as the history value to be used in the next 299 * iteration of the algorithm. 300 */ 301 memcpy(seed0, &digest[8], 8); 302 303 /* for debugging purposes only */ 304 #if 0 305 { 306 int i; 307 308 printf("to: "); 309 for (i = 0; i < 16; i++) 310 printf("%02x", digest[i]); 311 printf("\n"); 312 } 313 #endif 314 315 return 0; 316 } 317 /* 318 * Get interface identifier for the specified interface. 319 * XXX assumes single sockaddr_dl (AF_LINK address) per an interfacea 320 * 321 * in6 - upper 64bits are preserved 322 */ 323 int 324 in6_get_hw_ifid(struct ifnet *ifp, struct in6_addr *in6) 325 { 326 struct ifaddr *ifa; 327 const struct sockaddr_dl *sdl; 328 const char *addr; 329 size_t addrlen; 330 static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; 331 static u_int8_t allone[8] = 332 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 333 334 IFADDR_FOREACH(ifa, ifp) { 335 if (ifa->ifa_addr->sa_family != AF_LINK) 336 continue; 337 sdl = satocsdl(ifa->ifa_addr); 338 if (sdl == NULL) 339 continue; 340 if (sdl->sdl_alen == 0) 341 continue; 342 343 goto found; 344 } 345 346 return -1; 347 348 found: 349 addr = CLLADDR(sdl); 350 addrlen = sdl->sdl_alen; 351 352 switch (ifp->if_type) { 353 case IFT_IEEE1394: 354 case IFT_IEEE80211: 355 /* IEEE1394 uses 16byte length address starting with EUI64 */ 356 if (addrlen > 8) 357 addrlen = 8; 358 break; 359 default: 360 break; 361 } 362 363 /* get EUI64 */ 364 switch (ifp->if_type) { 365 /* IEEE802/EUI64 cases - what others? */ 366 case IFT_ETHER: 367 case IFT_FDDI: 368 case IFT_ATM: 369 case IFT_IEEE1394: 370 case IFT_IEEE80211: 371 /* look at IEEE802/EUI64 only */ 372 if (addrlen != 8 && addrlen != 6) 373 return -1; 374 375 /* 376 * check for invalid MAC address - on bsdi, we see it a lot 377 * since wildboar configures all-zero MAC on pccard before 378 * card insertion. 379 */ 380 if (memcmp(addr, allzero, addrlen) == 0) 381 return -1; 382 if (memcmp(addr, allone, addrlen) == 0) 383 return -1; 384 385 /* make EUI64 address */ 386 if (addrlen == 8) 387 memcpy(&in6->s6_addr[8], addr, 8); 388 else if (addrlen == 6) { 389 in6->s6_addr[8] = addr[0]; 390 in6->s6_addr[9] = addr[1]; 391 in6->s6_addr[10] = addr[2]; 392 in6->s6_addr[11] = 0xff; 393 in6->s6_addr[12] = 0xfe; 394 in6->s6_addr[13] = addr[3]; 395 in6->s6_addr[14] = addr[4]; 396 in6->s6_addr[15] = addr[5]; 397 } 398 break; 399 400 case IFT_ARCNET: 401 if (addrlen != 1) 402 return -1; 403 if (!addr[0]) 404 return -1; 405 406 memset(&in6->s6_addr[8], 0, 8); 407 in6->s6_addr[15] = addr[0]; 408 409 /* 410 * due to insufficient bitwidth, we mark it local. 411 */ 412 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 413 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 414 break; 415 416 case IFT_GIF: 417 #ifdef IFT_STF 418 case IFT_STF: 419 #endif 420 /* 421 * RFC2893 says: "SHOULD use IPv4 address as ifid source". 422 * however, IPv4 address is not very suitable as unique 423 * identifier source (can be renumbered). 424 * we don't do this. 425 */ 426 return -1; 427 428 default: 429 return -1; 430 } 431 432 /* sanity check: g bit must not indicate "group" */ 433 if (EUI64_GROUP(in6)) 434 return -1; 435 436 /* convert EUI64 into IPv6 interface identifier */ 437 EUI64_TO_IFID(in6); 438 439 /* 440 * sanity check: ifid must not be all zero, avoid conflict with 441 * subnet router anycast 442 */ 443 if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 && 444 memcmp(&in6->s6_addr[9], allzero, 7) == 0) { 445 return -1; 446 } 447 448 return 0; 449 } 450 451 /* 452 * Get interface identifier for the specified interface. If it is not 453 * available on ifp0, borrow interface identifier from other information 454 * sources. 455 * 456 * altifp - secondary EUI64 source 457 */ 458 static int 459 get_ifid(struct ifnet *ifp0, struct ifnet *altifp, 460 struct in6_addr *in6) 461 { 462 struct ifnet *ifp; 463 464 /* first, try to get it from the interface itself */ 465 if (in6_get_hw_ifid(ifp0, in6) == 0) { 466 nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n", 467 if_name(ifp0))); 468 goto success; 469 } 470 471 /* try secondary EUI64 source. this basically is for ATM PVC */ 472 if (altifp && in6_get_hw_ifid(altifp, in6) == 0) { 473 nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n", 474 if_name(ifp0), if_name(altifp))); 475 goto success; 476 } 477 478 /* next, try to get it from some other hardware interface */ 479 TAILQ_FOREACH(ifp, &ifnet, if_list) { 480 if (ifp == ifp0) 481 continue; 482 if (in6_get_hw_ifid(ifp, in6) != 0) 483 continue; 484 485 /* 486 * to borrow ifid from other interface, ifid needs to be 487 * globally unique 488 */ 489 if (IFID_UNIVERSAL(in6)) { 490 nd6log((LOG_DEBUG, 491 "%s: borrow interface identifier from %s\n", 492 if_name(ifp0), if_name(ifp))); 493 goto success; 494 } 495 } 496 497 #if 0 498 /* get from hostid - only for certain architectures */ 499 if (get_hostid_ifid(ifp, in6) == 0) { 500 nd6log((LOG_DEBUG, 501 "%s: interface identifier generated by hostid\n", 502 if_name(ifp0))); 503 goto success; 504 } 505 #endif 506 507 /* last resort: get from random number source */ 508 if (get_rand_ifid(ifp, in6) == 0) { 509 nd6log((LOG_DEBUG, 510 "%s: interface identifier generated by random number\n", 511 if_name(ifp0))); 512 goto success; 513 } 514 515 printf("%s: failed to get interface identifier\n", if_name(ifp0)); 516 return -1; 517 518 success: 519 nd6log((LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n", 520 if_name(ifp0), in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10], 521 in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13], 522 in6->s6_addr[14], in6->s6_addr[15])); 523 return 0; 524 } 525 526 /* 527 * altifp - secondary EUI64 source 528 */ 529 530 static int 531 in6_ifattach_linklocal(struct ifnet *ifp, struct ifnet *altifp) 532 { 533 struct in6_ifaddr *ia; 534 struct in6_aliasreq ifra; 535 struct nd_prefixctl pr0; 536 int i, error; 537 538 /* 539 * configure link-local address. 540 */ 541 memset(&ifra, 0, sizeof(ifra)); 542 543 /* 544 * in6_update_ifa() does not use ifra_name, but we accurately set it 545 * for safety. 546 */ 547 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 548 549 ifra.ifra_addr.sin6_family = AF_INET6; 550 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); 551 ifra.ifra_addr.sin6_addr.s6_addr32[0] = htonl(0xfe800000); 552 ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0; 553 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 554 ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0; 555 ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1); 556 } else { 557 if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) { 558 nd6log((LOG_ERR, 559 "%s: no ifid available\n", if_name(ifp))); 560 return -1; 561 } 562 } 563 if (in6_setscope(&ifra.ifra_addr.sin6_addr, ifp, NULL)) 564 return -1; 565 566 sockaddr_in6_init(&ifra.ifra_prefixmask, &in6mask64, 0, 0, 0); 567 /* link-local addresses should NEVER expire. */ 568 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 569 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 570 571 /* 572 * Now call in6_update_ifa() to do a bunch of procedures to configure 573 * a link-local address. We can set the 3rd argument to NULL, because 574 * we know there's no other link-local address on the interface 575 * and therefore we are adding one (instead of updating one). 576 */ 577 if ((error = in6_update_ifa(ifp, &ifra, NULL, 578 IN6_IFAUPDATE_DADDELAY)) != 0) { 579 /* 580 * XXX: When the interface does not support IPv6, this call 581 * would fail in the SIOCSIFADDR ioctl. I believe the 582 * notification is rather confusing in this case, so just 583 * suppress it. (jinmei@kame.net 20010130) 584 */ 585 if (error != EAFNOSUPPORT) 586 nd6log((LOG_NOTICE, "in6_ifattach_linklocal: failed to " 587 "configure a link-local address on %s " 588 "(errno=%d)\n", 589 if_name(ifp), error)); 590 return -1; 591 } 592 593 ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */ 594 #ifdef DIAGNOSTIC 595 if (!ia) { 596 panic("ia == NULL in in6_ifattach_linklocal"); 597 /* NOTREACHED */ 598 } 599 #endif 600 601 /* 602 * Make the link-local prefix (fe80::/64%link) as on-link. 603 * Since we'd like to manage prefixes separately from addresses, 604 * we make an ND6 prefix structure for the link-local prefix, 605 * and add it to the prefix list as a never-expire prefix. 606 * XXX: this change might affect some existing code base... 607 */ 608 memset(&pr0, 0, sizeof(pr0)); 609 pr0.ndpr_ifp = ifp; 610 /* this should be 64 at this moment. */ 611 pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL); 612 pr0.ndpr_prefix = ifra.ifra_addr; 613 /* apply the mask for safety. (nd6_prelist_add will apply it again) */ 614 for (i = 0; i < 4; i++) { 615 pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &= 616 in6mask64.s6_addr32[i]; 617 } 618 /* 619 * Initialize parameters. The link-local prefix must always be 620 * on-link, and its lifetimes never expire. 621 */ 622 pr0.ndpr_raf_onlink = 1; 623 pr0.ndpr_raf_auto = 1; /* probably meaningless */ 624 pr0.ndpr_vltime = ND6_INFINITE_LIFETIME; 625 pr0.ndpr_pltime = ND6_INFINITE_LIFETIME; 626 /* 627 * Since there is no other link-local addresses, nd6_prefix_lookup() 628 * probably returns NULL. However, we cannot always expect the result. 629 * For example, if we first remove the (only) existing link-local 630 * address, and then reconfigure another one, the prefix is still 631 * valid with referring to the old link-local address. 632 */ 633 if (nd6_prefix_lookup(&pr0) == NULL) { 634 if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0) 635 return error; 636 } 637 638 return 0; 639 } 640 641 /* 642 * ifp - mut be IFT_LOOP 643 */ 644 645 static int 646 in6_ifattach_loopback(struct ifnet *ifp) 647 { 648 struct in6_aliasreq ifra; 649 int error; 650 651 memset(&ifra, 0, sizeof(ifra)); 652 653 /* 654 * in6_update_ifa() does not use ifra_name, but we accurately set it 655 * for safety. 656 */ 657 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 658 659 sockaddr_in6_init(&ifra.ifra_prefixmask, &in6mask128, 0, 0, 0); 660 661 /* 662 * Always initialize ia_dstaddr (= broadcast address) to loopback 663 * address. Follows IPv4 practice - see in_ifinit(). 664 */ 665 sockaddr_in6_init(&ifra.ifra_dstaddr, &in6addr_loopback, 0, 0, 0); 666 667 sockaddr_in6_init(&ifra.ifra_addr, &in6addr_loopback, 0, 0, 0); 668 669 /* the loopback address should NEVER expire. */ 670 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 671 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 672 673 /* we don't need to perform DAD on loopback interfaces. */ 674 ifra.ifra_flags |= IN6_IFF_NODAD; 675 676 /* 677 * We are sure that this is a newly assigned address, so we can set 678 * NULL to the 3rd arg. 679 */ 680 if ((error = in6_update_ifa(ifp, &ifra, NULL, 0)) != 0) { 681 nd6log((LOG_ERR, "in6_ifattach_loopback: failed to configure " 682 "the loopback address on %s (errno=%d)\n", 683 if_name(ifp), error)); 684 return -1; 685 } 686 687 return 0; 688 } 689 690 /* 691 * compute NI group address, based on the current hostname setting. 692 * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later). 693 * 694 * when ifp == NULL, the caller is responsible for filling scopeid. 695 */ 696 int 697 in6_nigroup(struct ifnet *ifp, const char *name, int namelen, 698 struct sockaddr_in6 *sa6) 699 { 700 const char *p; 701 u_int8_t *q; 702 MD5_CTX ctxt; 703 u_int8_t digest[16]; 704 u_int8_t l; 705 u_int8_t n[64]; /* a single label must not exceed 63 chars */ 706 707 if (!namelen || !name) 708 return -1; 709 710 p = name; 711 while (p && *p && *p != '.' && p - name < namelen) 712 p++; 713 if (p - name > sizeof(n) - 1) 714 return -1; /* label too long */ 715 l = p - name; 716 strncpy((char *)n, name, l); 717 n[(int)l] = '\0'; 718 for (q = n; *q; q++) { 719 if ('A' <= *q && *q <= 'Z') 720 *q = *q - 'A' + 'a'; 721 } 722 723 /* generate 8 bytes of pseudo-random value. */ 724 memset(&ctxt, 0, sizeof(ctxt)); 725 MD5Init(&ctxt); 726 MD5Update(&ctxt, &l, sizeof(l)); 727 MD5Update(&ctxt, n, l); 728 MD5Final(digest, &ctxt); 729 730 memset(sa6, 0, sizeof(*sa6)); 731 sa6->sin6_family = AF_INET6; 732 sa6->sin6_len = sizeof(*sa6); 733 sa6->sin6_addr.s6_addr16[0] = htons(0xff02); 734 sa6->sin6_addr.s6_addr8[11] = 2; 735 memcpy(&sa6->sin6_addr.s6_addr32[3], digest, 736 sizeof(sa6->sin6_addr.s6_addr32[3])); 737 if (in6_setscope(&sa6->sin6_addr, ifp, NULL)) 738 return -1; /* XXX: should not fail */ 739 740 return 0; 741 } 742 743 /* 744 * XXX multiple loopback interface needs more care. for instance, 745 * nodelocal address needs to be configured onto only one of them. 746 * XXX multiple link-local address case 747 * 748 * altifp - secondary EUI64 source 749 */ 750 void 751 in6_ifattach(struct ifnet *ifp, struct ifnet *altifp) 752 { 753 struct in6_ifaddr *ia; 754 struct in6_addr in6; 755 756 /* some of the interfaces are inherently not IPv6 capable */ 757 switch (ifp->if_type) { 758 case IFT_BRIDGE: 759 #ifdef IFT_PFLOG 760 case IFT_PFLOG: 761 #endif 762 #ifdef IFT_PFSYNC 763 case IFT_PFSYNC: 764 #endif 765 return; 766 } 767 768 /* 769 * if link mtu is too small, don't try to configure IPv6. 770 * remember there could be some link-layer that has special 771 * fragmentation logic. 772 */ 773 if (ifp->if_mtu < IPV6_MMTU) { 774 nd6log((LOG_INFO, "in6_ifattach: " 775 "%s has too small MTU, IPv6 not enabled\n", 776 if_name(ifp))); 777 return; 778 } 779 780 /* create a multicast kludge storage (if we have not had one) */ 781 in6_createmkludge(ifp); 782 783 /* 784 * quirks based on interface type 785 */ 786 switch (ifp->if_type) { 787 #ifdef IFT_STF 788 case IFT_STF: 789 /* 790 * 6to4 interface is a very special kind of beast. 791 * no multicast, no linklocal. RFC2529 specifies how to make 792 * linklocals for 6to4 interface, but there's no use and 793 * it is rather harmful to have one. 794 */ 795 return; 796 #endif 797 case IFT_CARP: 798 return; 799 default: 800 break; 801 } 802 803 /* 804 * usually, we require multicast capability to the interface 805 */ 806 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 807 nd6log((LOG_INFO, "in6_ifattach: " 808 "%s is not multicast capable, IPv6 not enabled\n", 809 if_name(ifp))); 810 return; 811 } 812 813 /* 814 * assign loopback address for loopback interface. 815 * XXX multiple loopback interface case. 816 */ 817 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 818 in6 = in6addr_loopback; 819 if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) { 820 if (in6_ifattach_loopback(ifp) != 0) 821 return; 822 } 823 } 824 825 /* 826 * assign a link-local address, if there's none. 827 */ 828 if (ip6_auto_linklocal) { 829 ia = in6ifa_ifpforlinklocal(ifp, 0); 830 if (ia == NULL && in6_ifattach_linklocal(ifp, altifp) != 0) { 831 printf("%s: cannot assign link-local address\n", 832 ifp->if_xname); 833 } 834 } 835 } 836 837 /* 838 * NOTE: in6_ifdetach() does not support loopback if at this moment. 839 * We don't need this function in bsdi, because interfaces are never removed 840 * from the ifnet list in bsdi. 841 */ 842 void 843 in6_ifdetach(struct ifnet *ifp) 844 { 845 struct in6_ifaddr *ia, *oia; 846 struct ifaddr *ifa, *next; 847 struct rtentry *rt; 848 short rtflags; 849 struct in6_multi_mship *imm; 850 851 /* remove ip6_mrouter stuff */ 852 ip6_mrouter_detach(ifp); 853 854 /* remove neighbor management table */ 855 nd6_purge(ifp); 856 857 /* XXX this code is duplicated in in6_purgeif() --dyoung */ 858 /* nuke any of IPv6 addresses we have */ 859 if_purgeaddrs(ifp, AF_INET6, in6_purgeaddr); 860 861 /* XXX isn't this code is redundant, given the above? --dyoung */ 862 /* XXX doesn't this code replicate code in in6_purgeaddr() ? --dyoung */ 863 /* undo everything done by in6_ifattach(), just in case */ 864 for (ifa = IFADDR_FIRST(ifp); ifa != NULL; ifa = next) { 865 next = IFADDR_NEXT(ifa); 866 867 if (ifa->ifa_addr->sa_family != AF_INET6 868 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) { 869 continue; 870 } 871 872 ia = (struct in6_ifaddr *)ifa; 873 874 /* 875 * leave from multicast groups we have joined for the interface 876 */ 877 while ((imm = LIST_FIRST(&ia->ia6_memberships)) != NULL) { 878 LIST_REMOVE(imm, i6mm_chain); 879 in6_leavegroup(imm); 880 } 881 882 /* remove from the routing table */ 883 if ((ia->ia_flags & IFA_ROUTE) && 884 (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0))) { 885 rtflags = rt->rt_flags; 886 rtfree(rt); 887 rtrequest(RTM_DELETE, (struct sockaddr *)&ia->ia_addr, 888 (struct sockaddr *)&ia->ia_addr, 889 (struct sockaddr *)&ia->ia_prefixmask, 890 rtflags, (struct rtentry **)0); 891 } 892 893 /* remove from the linked list */ 894 ifa_remove(ifp, &ia->ia_ifa); 895 896 /* also remove from the IPv6 address chain(itojun&jinmei) */ 897 oia = ia; 898 if (oia == (ia = in6_ifaddr)) 899 in6_ifaddr = ia->ia_next; 900 else { 901 while (ia->ia_next && (ia->ia_next != oia)) 902 ia = ia->ia_next; 903 if (ia->ia_next) 904 ia->ia_next = oia->ia_next; 905 else { 906 nd6log((LOG_ERR, 907 "%s: didn't unlink in6ifaddr from list\n", 908 if_name(ifp))); 909 } 910 } 911 912 IFAFREE(&oia->ia_ifa); 913 } 914 915 /* cleanup multicast address kludge table, if there is any */ 916 in6_purgemkludge(ifp); 917 918 /* 919 * remove neighbor management table. we call it twice just to make 920 * sure we nuke everything. maybe we need just one call. 921 * XXX: since the first call did not release addresses, some prefixes 922 * might remain. We should call nd6_purge() again to release the 923 * prefixes after removing all addresses above. 924 * (Or can we just delay calling nd6_purge until at this point?) 925 */ 926 nd6_purge(ifp); 927 } 928 929 int 930 in6_get_tmpifid(struct ifnet *ifp, u_int8_t *retbuf, 931 const u_int8_t *baseid, int generate) 932 { 933 u_int8_t nullbuf[8]; 934 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 935 936 memset(nullbuf, 0, sizeof(nullbuf)); 937 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) { 938 /* we've never created a random ID. Create a new one. */ 939 generate = 1; 940 } 941 942 if (generate) { 943 memcpy(ndi->randomseed1, baseid, sizeof(ndi->randomseed1)); 944 945 /* generate_tmp_ifid will update seedn and buf */ 946 (void)generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1, 947 ndi->randomid); 948 } 949 memcpy(retbuf, ndi->randomid, 8); 950 if (generate && memcmp(retbuf, nullbuf, sizeof(nullbuf)) == 0) { 951 /* generate_tmp_ifid could not found a good ID. */ 952 return -1; 953 } 954 955 return 0; 956 } 957 958 void 959 in6_tmpaddrtimer(void *ignored_arg) 960 { 961 struct nd_ifinfo *ndi; 962 u_int8_t nullbuf[8]; 963 struct ifnet *ifp; 964 int s = splsoftnet(); 965 966 callout_reset(&in6_tmpaddrtimer_ch, 967 (ip6_temp_preferred_lifetime - ip6_desync_factor - 968 ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, NULL); 969 970 memset(nullbuf, 0, sizeof(nullbuf)); 971 TAILQ_FOREACH(ifp, &ifnet, if_list) { 972 ndi = ND_IFINFO(ifp); 973 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) { 974 /* 975 * We've been generating a random ID on this interface. 976 * Create a new one. 977 */ 978 (void)generate_tmp_ifid(ndi->randomseed0, 979 ndi->randomseed1, ndi->randomid); 980 } 981 } 982 983 splx(s); 984 } 985