1 /* $NetBSD: in6_ifattach.c,v 1.85 2009/09/19 13:11:02 christos 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 1.85 2009/09/19 13:11:02 christos Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/kmem.h> 39 #include <sys/malloc.h> 40 #include <sys/socket.h> 41 #include <sys/sockio.h> 42 #include <sys/kernel.h> 43 #include <sys/syslog.h> 44 #include <sys/md5.h> 45 #include <sys/socketvar.h> 46 47 #include <net/if.h> 48 #include <net/if_dl.h> 49 #include <net/if_types.h> 50 #include <net/route.h> 51 52 #include <netinet/in.h> 53 #include <netinet/in_var.h> 54 55 #include <netinet/ip6.h> 56 #include <netinet6/in6_ifattach.h> 57 #include <netinet6/ip6_var.h> 58 #include <netinet6/nd6.h> 59 #include <netinet6/ip6_mroute.h> 60 #include <netinet6/scope6_var.h> 61 62 #include <net/net_osdep.h> 63 64 unsigned long in6_maxmtu = 0; 65 66 int ip6_auto_linklocal = 1; /* enable by default */ 67 68 callout_t in6_tmpaddrtimer_ch; 69 70 71 #if 0 72 static int get_hostid_ifid(struct ifnet *, struct in6_addr *); 73 #endif 74 static int get_rand_ifid(struct ifnet *, struct in6_addr *); 75 static int generate_tmp_ifid(u_int8_t *, const u_int8_t *, u_int8_t *); 76 static int get_ifid(struct ifnet *, struct ifnet *, struct in6_addr *); 77 static int in6_ifattach_linklocal(struct ifnet *, struct ifnet *); 78 static int in6_ifattach_loopback(struct ifnet *); 79 80 #define EUI64_GBIT 0x01 81 #define EUI64_UBIT 0x02 82 #define EUI64_TO_IFID(in6) do {(in6)->s6_addr[8] ^= EUI64_UBIT; } while (/*CONSTCOND*/ 0) 83 #define EUI64_GROUP(in6) ((in6)->s6_addr[8] & EUI64_GBIT) 84 #define EUI64_INDIVIDUAL(in6) (!EUI64_GROUP(in6)) 85 #define EUI64_LOCAL(in6) ((in6)->s6_addr[8] & EUI64_UBIT) 86 #define EUI64_UNIVERSAL(in6) (!EUI64_LOCAL(in6)) 87 88 #define IFID_LOCAL(in6) (!EUI64_LOCAL(in6)) 89 #define IFID_UNIVERSAL(in6) (!EUI64_UNIVERSAL(in6)) 90 91 #define GEN_TEMPID_RETRY_MAX 5 92 93 #if 0 94 /* 95 * Generate a last-resort interface identifier from hostid. 96 * works only for certain architectures (like sparc). 97 * also, using hostid itself may constitute a privacy threat, much worse 98 * than MAC addresses (hostids are used for software licensing). 99 * maybe we should use MD5(hostid) instead. 100 * 101 * in6 - upper 64bits are preserved 102 */ 103 static int 104 get_hostid_ifid(struct ifnet *ifp, struct in6_addr *in6) 105 { 106 int off, len; 107 static const uint8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; 108 static const uint8_t allone[8] = 109 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 110 111 if (!hostid) 112 return -1; 113 114 /* get up to 8 bytes from the hostid field - should we get */ 115 len = (sizeof(hostid) > 8) ? 8 : sizeof(hostid); 116 off = sizeof(*in6) - len; 117 memcpy(&in6->s6_addr[off], &hostid, len); 118 119 /* make sure we do not return anything bogus */ 120 if (memcmp(&in6->s6_addr[8], allzero, sizeof(allzero))) 121 return -1; 122 if (memcmp(&in6->s6_addr[8], allone, sizeof(allone))) 123 return -1; 124 125 /* make sure to set "u" bit to local, and "g" bit to individual. */ 126 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 127 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 128 129 /* convert EUI64 into IPv6 interface identifier */ 130 EUI64_TO_IFID(in6); 131 132 return 0; 133 } 134 #endif 135 136 /* 137 * Generate a last-resort interface identifier, when the machine has no 138 * IEEE802/EUI64 address sources. 139 * The goal here is to get an interface identifier that is 140 * (1) random enough and (2) does not change across reboot. 141 * We currently use MD5(hostname) for it. 142 */ 143 static int 144 get_rand_ifid(struct ifnet *ifp, 145 struct in6_addr *in6) /* upper 64bits are preserved */ 146 { 147 MD5_CTX ctxt; 148 u_int8_t digest[16]; 149 150 #if 0 151 /* we need at least several letters as seed for ifid */ 152 if (hostnamelen < 3) 153 return -1; 154 #endif 155 156 /* generate 8 bytes of pseudo-random value. */ 157 memset(&ctxt, 0, sizeof(ctxt)); 158 MD5Init(&ctxt); 159 MD5Update(&ctxt, (u_char *)hostname, hostnamelen); 160 MD5Final(digest, &ctxt); 161 162 /* assumes sizeof(digest) > sizeof(ifid) */ 163 memcpy(&in6->s6_addr[8], digest, 8); 164 165 /* make sure to set "u" bit to local, and "g" bit to individual. */ 166 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 167 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 168 169 /* convert EUI64 into IPv6 interface identifier */ 170 EUI64_TO_IFID(in6); 171 172 return 0; 173 } 174 175 static int 176 generate_tmp_ifid(u_int8_t *seed0, const u_int8_t *seed1, u_int8_t *ret) 177 { 178 MD5_CTX ctxt; 179 u_int8_t seed[16], digest[16], nullbuf[8]; 180 u_int32_t val32; 181 /* 182 * interface ID for subnet anycast addresses. 183 * XXX: we assume the unicast address range that requires IDs 184 * in EUI-64 format. 185 */ 186 static const uint8_t anycast_id[8] = { 0xfd, 0xff, 0xff, 0xff, 187 0xff, 0xff, 0xff, 0x80 }; 188 static const uint8_t isatap_id[4] = { 0x00, 0x00, 0x5e, 0xfe }; 189 int badid, retry = 0; 190 191 /* If there's no hisotry, start with a random seed. */ 192 memset(nullbuf, 0, sizeof(nullbuf)); 193 if (memcmp(nullbuf, seed0, sizeof(nullbuf)) == 0) { 194 int i; 195 196 for (i = 0; i < 2; i++) { 197 val32 = arc4random(); 198 memcpy(seed + sizeof(val32) * i, &val32, sizeof(val32)); 199 } 200 } else 201 memcpy(seed, seed0, 8); 202 203 /* copy the right-most 64-bits of the given address */ 204 /* XXX assumption on the size of IFID */ 205 memcpy(&seed[8], seed1, 8); 206 207 again: 208 /* for debugging purposes only */ 209 #if 0 210 { 211 int i; 212 213 printf("generate_tmp_ifid: new randomized ID from: "); 214 for (i = 0; i < 16; i++) 215 printf("%02x", seed[i]); 216 printf(" "); 217 } 218 #endif 219 220 /* generate 16 bytes of pseudo-random value. */ 221 memset(&ctxt, 0, sizeof(ctxt)); 222 MD5Init(&ctxt); 223 MD5Update(&ctxt, seed, sizeof(seed)); 224 MD5Final(digest, &ctxt); 225 226 /* 227 * draft-ietf-ipngwg-temp-addresses-v2-00.txt 3.2.1. (3) 228 * Take the left-most 64-bits of the MD5 digest and set bit 6 (the 229 * left-most bit is numbered 0) to zero. 230 */ 231 memcpy(ret, digest, 8); 232 ret[0] &= ~EUI64_UBIT; 233 234 /* 235 * Reject inappropriate identifiers according to 236 * draft-ietf-ipngwg-temp-addresses-v2-00.txt 3.2.1. (4) 237 * At this moment, we reject following cases: 238 * - all 0 identifier 239 * - identifiers that conflict with reserved subnet anycast addresses, 240 * which are defined in RFC 2526. 241 * - identifiers that conflict with ISATAP addresses 242 * - identifiers used in our own addresses 243 */ 244 badid = 0; 245 if (memcmp(nullbuf, ret, sizeof(nullbuf)) == 0) 246 badid = 1; 247 else if (memcmp(anycast_id, ret, 7) == 0 && 248 (anycast_id[7] & ret[7]) == anycast_id[7]) { 249 badid = 1; 250 } else if (memcmp(isatap_id, ret, sizeof(isatap_id)) == 0) 251 badid = 1; 252 else { 253 struct in6_ifaddr *ia; 254 255 for (ia = in6_ifaddr; ia; ia = ia->ia_next) { 256 if (!memcmp(&ia->ia_addr.sin6_addr.s6_addr[8], 257 ret, 8)) { 258 badid = 1; 259 break; 260 } 261 } 262 } 263 264 /* 265 * In the event that an unacceptable identifier has been generated, 266 * restart the process, using the right-most 64 bits of the MD5 digest 267 * obtained in place of the history value. 268 */ 269 if (badid) { 270 /* for debugging purposes only */ 271 #if 0 272 { 273 int i; 274 275 printf("unacceptable random ID: "); 276 for (i = 0; i < 16; i++) 277 printf("%02x", digest[i]); 278 printf("\n"); 279 } 280 #endif 281 282 if (++retry < GEN_TEMPID_RETRY_MAX) { 283 memcpy(seed, &digest[8], 8); 284 goto again; 285 } else { 286 /* 287 * We're so unlucky. Give up for now, and return 288 * all 0 IDs to tell the caller not to make a 289 * temporary address. 290 */ 291 nd6log((LOG_NOTICE, 292 "generate_tmp_ifid: never found a good ID\n")); 293 memset(ret, 0, 8); 294 } 295 } 296 297 /* 298 * draft-ietf-ipngwg-temp-addresses-v2-00.txt 3.2.1. (6) 299 * Take the rightmost 64-bits of the MD5 digest and save them in 300 * stable storage as the history value to be used in the next 301 * iteration of the algorithm. 302 */ 303 memcpy(seed0, &digest[8], 8); 304 305 /* for debugging purposes only */ 306 #if 0 307 { 308 int i; 309 310 printf("to: "); 311 for (i = 0; i < 16; i++) 312 printf("%02x", digest[i]); 313 printf("\n"); 314 } 315 #endif 316 317 return 0; 318 } 319 320 /* 321 * Get interface identifier for the specified interface. 322 * 323 * in6 - upper 64bits are preserved 324 */ 325 int 326 in6_get_hw_ifid(struct ifnet *ifp, struct in6_addr *in6) 327 { 328 struct ifaddr *ifa; 329 const struct sockaddr_dl *sdl = NULL, *tsdl; 330 const char *addr; 331 size_t addrlen; 332 static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; 333 static u_int8_t allone[8] = 334 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 335 336 IFADDR_FOREACH(ifa, ifp) { 337 if (ifa->ifa_addr->sa_family != AF_LINK) 338 continue; 339 tsdl = satocsdl(ifa->ifa_addr); 340 if (tsdl == NULL || tsdl->sdl_alen == 0) 341 continue; 342 if (sdl == NULL || ifa == ifp->if_dl || ifa == ifp->if_hwdl) 343 sdl = tsdl; 344 if (ifa == ifp->if_hwdl) 345 break; 346 } 347 348 if (sdl == NULL) 349 return -1; 350 351 addr = CLLADDR(sdl); 352 addrlen = sdl->sdl_alen; 353 354 switch (ifp->if_type) { 355 case IFT_IEEE1394: 356 case IFT_IEEE80211: 357 /* IEEE1394 uses 16byte length address starting with EUI64 */ 358 if (addrlen > 8) 359 addrlen = 8; 360 break; 361 default: 362 break; 363 } 364 365 /* get EUI64 */ 366 switch (ifp->if_type) { 367 /* IEEE802/EUI64 cases - what others? */ 368 case IFT_ETHER: 369 case IFT_FDDI: 370 case IFT_ATM: 371 case IFT_IEEE1394: 372 case IFT_IEEE80211: 373 /* look at IEEE802/EUI64 only */ 374 if (addrlen != 8 && addrlen != 6) 375 return -1; 376 377 /* 378 * check for invalid MAC address - on bsdi, we see it a lot 379 * since wildboar configures all-zero MAC on pccard before 380 * card insertion. 381 */ 382 if (memcmp(addr, allzero, addrlen) == 0) 383 return -1; 384 if (memcmp(addr, allone, addrlen) == 0) 385 return -1; 386 387 /* make EUI64 address */ 388 if (addrlen == 8) 389 memcpy(&in6->s6_addr[8], addr, 8); 390 else if (addrlen == 6) { 391 in6->s6_addr[8] = addr[0]; 392 in6->s6_addr[9] = addr[1]; 393 in6->s6_addr[10] = addr[2]; 394 in6->s6_addr[11] = 0xff; 395 in6->s6_addr[12] = 0xfe; 396 in6->s6_addr[13] = addr[3]; 397 in6->s6_addr[14] = addr[4]; 398 in6->s6_addr[15] = addr[5]; 399 } 400 break; 401 402 case IFT_ARCNET: 403 if (addrlen != 1) 404 return -1; 405 if (!addr[0]) 406 return -1; 407 408 memset(&in6->s6_addr[8], 0, 8); 409 in6->s6_addr[15] = addr[0]; 410 411 /* 412 * due to insufficient bitwidth, we mark it local. 413 */ 414 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 415 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 416 break; 417 418 case IFT_GIF: 419 #ifdef IFT_STF 420 case IFT_STF: 421 #endif 422 /* 423 * RFC2893 says: "SHOULD use IPv4 address as ifid source". 424 * however, IPv4 address is not very suitable as unique 425 * identifier source (can be renumbered). 426 * we don't do this. 427 */ 428 return -1; 429 430 default: 431 return -1; 432 } 433 434 /* sanity check: g bit must not indicate "group" */ 435 if (EUI64_GROUP(in6)) 436 return -1; 437 438 /* convert EUI64 into IPv6 interface identifier */ 439 EUI64_TO_IFID(in6); 440 441 /* 442 * sanity check: ifid must not be all zero, avoid conflict with 443 * subnet router anycast 444 */ 445 if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 && 446 memcmp(&in6->s6_addr[9], allzero, 7) == 0) { 447 return -1; 448 } 449 450 return 0; 451 } 452 453 /* 454 * Get interface identifier for the specified interface. If it is not 455 * available on ifp0, borrow interface identifier from other information 456 * sources. 457 * 458 * altifp - secondary EUI64 source 459 */ 460 static int 461 get_ifid(struct ifnet *ifp0, struct ifnet *altifp, 462 struct in6_addr *in6) 463 { 464 struct ifnet *ifp; 465 466 /* first, try to get it from the interface itself */ 467 if (in6_get_hw_ifid(ifp0, in6) == 0) { 468 nd6log((LOG_DEBUG, "%s: got interface identifier from itself\n", 469 if_name(ifp0))); 470 goto success; 471 } 472 473 /* try secondary EUI64 source. this basically is for ATM PVC */ 474 if (altifp && in6_get_hw_ifid(altifp, in6) == 0) { 475 nd6log((LOG_DEBUG, "%s: got interface identifier from %s\n", 476 if_name(ifp0), if_name(altifp))); 477 goto success; 478 } 479 480 /* next, try to get it from some other hardware interface */ 481 TAILQ_FOREACH(ifp, &ifnet, if_list) { 482 if (ifp == ifp0) 483 continue; 484 if (in6_get_hw_ifid(ifp, in6) != 0) 485 continue; 486 487 /* 488 * to borrow ifid from other interface, ifid needs to be 489 * globally unique 490 */ 491 if (IFID_UNIVERSAL(in6)) { 492 nd6log((LOG_DEBUG, 493 "%s: borrow interface identifier from %s\n", 494 if_name(ifp0), if_name(ifp))); 495 goto success; 496 } 497 } 498 499 #if 0 500 /* get from hostid - only for certain architectures */ 501 if (get_hostid_ifid(ifp, in6) == 0) { 502 nd6log((LOG_DEBUG, 503 "%s: interface identifier generated by hostid\n", 504 if_name(ifp0))); 505 goto success; 506 } 507 #endif 508 509 /* last resort: get from random number source */ 510 if (get_rand_ifid(ifp, in6) == 0) { 511 nd6log((LOG_DEBUG, 512 "%s: interface identifier generated by random number\n", 513 if_name(ifp0))); 514 goto success; 515 } 516 517 printf("%s: failed to get interface identifier\n", if_name(ifp0)); 518 return -1; 519 520 success: 521 nd6log((LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n", 522 if_name(ifp0), in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10], 523 in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13], 524 in6->s6_addr[14], in6->s6_addr[15])); 525 return 0; 526 } 527 528 /* 529 * altifp - secondary EUI64 source 530 */ 531 532 static int 533 in6_ifattach_linklocal(struct ifnet *ifp, struct ifnet *altifp) 534 { 535 struct in6_ifaddr *ia; 536 struct in6_aliasreq ifra; 537 struct nd_prefixctl pr0; 538 int i, error; 539 540 /* 541 * configure link-local address. 542 */ 543 memset(&ifra, 0, sizeof(ifra)); 544 545 /* 546 * in6_update_ifa() does not use ifra_name, but we accurately set it 547 * for safety. 548 */ 549 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 550 551 ifra.ifra_addr.sin6_family = AF_INET6; 552 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); 553 ifra.ifra_addr.sin6_addr.s6_addr32[0] = htonl(0xfe800000); 554 ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0; 555 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 556 ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0; 557 ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1); 558 } else { 559 if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) { 560 nd6log((LOG_ERR, 561 "%s: no ifid available\n", if_name(ifp))); 562 return -1; 563 } 564 } 565 if (in6_setscope(&ifra.ifra_addr.sin6_addr, ifp, NULL)) 566 return -1; 567 568 sockaddr_in6_init(&ifra.ifra_prefixmask, &in6mask64, 0, 0, 0); 569 /* link-local addresses should NEVER expire. */ 570 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 571 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 572 573 /* 574 * Now call in6_update_ifa() to do a bunch of procedures to configure 575 * a link-local address. We can set the 3rd argument to NULL, because 576 * we know there's no other link-local address on the interface 577 * and therefore we are adding one (instead of updating one). 578 */ 579 if ((error = in6_update_ifa(ifp, &ifra, NULL, 580 IN6_IFAUPDATE_DADDELAY)) != 0) { 581 /* 582 * XXX: When the interface does not support IPv6, this call 583 * would fail in the SIOCINITIFADDR ioctl. I believe the 584 * notification is rather confusing in this case, so just 585 * suppress it. (jinmei@kame.net 20010130) 586 */ 587 if (error != EAFNOSUPPORT) 588 nd6log((LOG_NOTICE, "in6_ifattach_linklocal: failed to " 589 "configure a link-local address on %s " 590 "(errno=%d)\n", 591 if_name(ifp), error)); 592 return -1; 593 } 594 595 ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */ 596 #ifdef DIAGNOSTIC 597 if (!ia) { 598 panic("ia == NULL in in6_ifattach_linklocal"); 599 /* NOTREACHED */ 600 } 601 #endif 602 603 /* 604 * Make the link-local prefix (fe80::/64%link) as on-link. 605 * Since we'd like to manage prefixes separately from addresses, 606 * we make an ND6 prefix structure for the link-local prefix, 607 * and add it to the prefix list as a never-expire prefix. 608 * XXX: this change might affect some existing code base... 609 */ 610 memset(&pr0, 0, sizeof(pr0)); 611 pr0.ndpr_ifp = ifp; 612 /* this should be 64 at this moment. */ 613 pr0.ndpr_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL); 614 pr0.ndpr_prefix = ifra.ifra_addr; 615 /* apply the mask for safety. (nd6_prelist_add will apply it again) */ 616 for (i = 0; i < 4; i++) { 617 pr0.ndpr_prefix.sin6_addr.s6_addr32[i] &= 618 in6mask64.s6_addr32[i]; 619 } 620 /* 621 * Initialize parameters. The link-local prefix must always be 622 * on-link, and its lifetimes never expire. 623 */ 624 pr0.ndpr_raf_onlink = 1; 625 pr0.ndpr_raf_auto = 1; /* probably meaningless */ 626 pr0.ndpr_vltime = ND6_INFINITE_LIFETIME; 627 pr0.ndpr_pltime = ND6_INFINITE_LIFETIME; 628 /* 629 * Since there is no other link-local addresses, nd6_prefix_lookup() 630 * probably returns NULL. However, we cannot always expect the result. 631 * For example, if we first remove the (only) existing link-local 632 * address, and then reconfigure another one, the prefix is still 633 * valid with referring to the old link-local address. 634 */ 635 if (nd6_prefix_lookup(&pr0) == NULL) { 636 if ((error = nd6_prelist_add(&pr0, NULL, NULL)) != 0) 637 return error; 638 } 639 640 return 0; 641 } 642 643 /* 644 * ifp - mut be IFT_LOOP 645 */ 646 647 static int 648 in6_ifattach_loopback(struct ifnet *ifp) 649 { 650 struct in6_aliasreq ifra; 651 int error; 652 653 memset(&ifra, 0, sizeof(ifra)); 654 655 /* 656 * in6_update_ifa() does not use ifra_name, but we accurately set it 657 * for safety. 658 */ 659 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 660 661 sockaddr_in6_init(&ifra.ifra_prefixmask, &in6mask128, 0, 0, 0); 662 663 /* 664 * Always initialize ia_dstaddr (= broadcast address) to loopback 665 * address. Follows IPv4 practice - see in_ifinit(). 666 */ 667 sockaddr_in6_init(&ifra.ifra_dstaddr, &in6addr_loopback, 0, 0, 0); 668 669 sockaddr_in6_init(&ifra.ifra_addr, &in6addr_loopback, 0, 0, 0); 670 671 /* the loopback address should NEVER expire. */ 672 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 673 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 674 675 /* we don't need to perform DAD on loopback interfaces. */ 676 ifra.ifra_flags |= IN6_IFF_NODAD; 677 678 /* 679 * We are sure that this is a newly assigned address, so we can set 680 * NULL to the 3rd arg. 681 */ 682 if ((error = in6_update_ifa(ifp, &ifra, NULL, 0)) != 0) { 683 nd6log((LOG_ERR, "in6_ifattach_loopback: failed to configure " 684 "the loopback address on %s (errno=%d)\n", 685 if_name(ifp), error)); 686 return -1; 687 } 688 689 return 0; 690 } 691 692 /* 693 * compute NI group address, based on the current hostname setting. 694 * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later). 695 * 696 * when ifp == NULL, the caller is responsible for filling scopeid. 697 */ 698 int 699 in6_nigroup(struct ifnet *ifp, const char *name, int namelen, 700 struct sockaddr_in6 *sa6) 701 { 702 const char *p; 703 u_int8_t *q; 704 MD5_CTX ctxt; 705 u_int8_t digest[16]; 706 u_int8_t l; 707 u_int8_t n[64]; /* a single label must not exceed 63 chars */ 708 709 if (!namelen || !name) 710 return -1; 711 712 p = name; 713 while (p && *p && *p != '.' && p - name < namelen) 714 p++; 715 if (p - name > sizeof(n) - 1) 716 return -1; /* label too long */ 717 l = p - name; 718 strncpy((char *)n, name, l); 719 n[(int)l] = '\0'; 720 for (q = n; *q; q++) { 721 if ('A' <= *q && *q <= 'Z') 722 *q = *q - 'A' + 'a'; 723 } 724 725 /* generate 8 bytes of pseudo-random value. */ 726 memset(&ctxt, 0, sizeof(ctxt)); 727 MD5Init(&ctxt); 728 MD5Update(&ctxt, &l, sizeof(l)); 729 MD5Update(&ctxt, n, l); 730 MD5Final(digest, &ctxt); 731 732 memset(sa6, 0, sizeof(*sa6)); 733 sa6->sin6_family = AF_INET6; 734 sa6->sin6_len = sizeof(*sa6); 735 sa6->sin6_addr.s6_addr16[0] = htons(0xff02); 736 sa6->sin6_addr.s6_addr8[11] = 2; 737 memcpy(&sa6->sin6_addr.s6_addr32[3], digest, 738 sizeof(sa6->sin6_addr.s6_addr32[3])); 739 if (in6_setscope(&sa6->sin6_addr, ifp, NULL)) 740 return -1; /* XXX: should not fail */ 741 742 return 0; 743 } 744 745 /* 746 * XXX multiple loopback interface needs more care. for instance, 747 * nodelocal address needs to be configured onto only one of them. 748 * XXX multiple link-local address case 749 * 750 * altifp - secondary EUI64 source 751 */ 752 void 753 in6_ifattach(struct ifnet *ifp, struct ifnet *altifp) 754 { 755 struct in6_ifaddr *ia; 756 struct in6_addr in6; 757 758 /* some of the interfaces are inherently not IPv6 capable */ 759 switch (ifp->if_type) { 760 case IFT_BRIDGE: 761 #ifdef IFT_PFLOG 762 case IFT_PFLOG: 763 #endif 764 #ifdef IFT_PFSYNC 765 case IFT_PFSYNC: 766 #endif 767 return; 768 } 769 770 /* 771 * if link mtu is too small, don't try to configure IPv6. 772 * remember there could be some link-layer that has special 773 * fragmentation logic. 774 */ 775 if (ifp->if_mtu < IPV6_MMTU) { 776 nd6log((LOG_INFO, "in6_ifattach: " 777 "%s has too small MTU, IPv6 not enabled\n", 778 if_name(ifp))); 779 return; 780 } 781 782 /* create a multicast kludge storage (if we have not had one) */ 783 in6_createmkludge(ifp); 784 785 /* 786 * quirks based on interface type 787 */ 788 switch (ifp->if_type) { 789 #ifdef IFT_STF 790 case IFT_STF: 791 /* 792 * 6to4 interface is a very special kind of beast. 793 * no multicast, no linklocal. RFC2529 specifies how to make 794 * linklocals for 6to4 interface, but there's no use and 795 * it is rather harmful to have one. 796 */ 797 return; 798 #endif 799 case IFT_CARP: 800 return; 801 default: 802 break; 803 } 804 805 /* 806 * usually, we require multicast capability to the interface 807 */ 808 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 809 nd6log((LOG_INFO, "in6_ifattach: " 810 "%s is not multicast capable, IPv6 not enabled\n", 811 if_name(ifp))); 812 return; 813 } 814 815 /* 816 * assign loopback address for loopback interface. 817 * XXX multiple loopback interface case. 818 */ 819 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 820 in6 = in6addr_loopback; 821 if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) { 822 if (in6_ifattach_loopback(ifp) != 0) 823 return; 824 } 825 } 826 827 /* 828 * assign a link-local address, if there's none. 829 */ 830 if (ip6_auto_linklocal) { 831 ia = in6ifa_ifpforlinklocal(ifp, 0); 832 if (ia == NULL && in6_ifattach_linklocal(ifp, altifp) != 0) { 833 printf("%s: cannot assign link-local address\n", 834 ifp->if_xname); 835 } 836 } 837 } 838 839 /* 840 * NOTE: in6_ifdetach() does not support loopback if at this moment. 841 * We don't need this function in bsdi, because interfaces are never removed 842 * from the ifnet list in bsdi. 843 */ 844 void 845 in6_ifdetach(struct ifnet *ifp) 846 { 847 struct in6_ifaddr *ia, *oia; 848 struct ifaddr *ifa, *next; 849 struct rtentry *rt; 850 short rtflags; 851 struct in6_multi_mship *imm; 852 853 /* remove ip6_mrouter stuff */ 854 ip6_mrouter_detach(ifp); 855 856 /* remove neighbor management table */ 857 nd6_purge(ifp); 858 859 /* XXX this code is duplicated in in6_purgeif() --dyoung */ 860 /* nuke any of IPv6 addresses we have */ 861 if_purgeaddrs(ifp, AF_INET6, in6_purgeaddr); 862 863 /* XXX isn't this code is redundant, given the above? --dyoung */ 864 /* XXX doesn't this code replicate code in in6_purgeaddr() ? --dyoung */ 865 /* undo everything done by in6_ifattach(), just in case */ 866 for (ifa = IFADDR_FIRST(ifp); ifa != NULL; ifa = next) { 867 next = IFADDR_NEXT(ifa); 868 869 if (ifa->ifa_addr->sa_family != AF_INET6 870 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) { 871 continue; 872 } 873 874 ia = (struct in6_ifaddr *)ifa; 875 876 /* 877 * leave from multicast groups we have joined for the interface 878 */ 879 while ((imm = LIST_FIRST(&ia->ia6_memberships)) != NULL) { 880 LIST_REMOVE(imm, i6mm_chain); 881 in6_leavegroup(imm); 882 } 883 884 /* remove from the routing table */ 885 if ((ia->ia_flags & IFA_ROUTE) && 886 (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0))) { 887 rtflags = rt->rt_flags; 888 rtfree(rt); 889 rtrequest(RTM_DELETE, (struct sockaddr *)&ia->ia_addr, 890 (struct sockaddr *)&ia->ia_addr, 891 (struct sockaddr *)&ia->ia_prefixmask, 892 rtflags, (struct rtentry **)0); 893 } 894 895 /* remove from the linked list */ 896 ifa_remove(ifp, &ia->ia_ifa); 897 898 /* also remove from the IPv6 address chain(itojun&jinmei) */ 899 oia = ia; 900 if (oia == (ia = in6_ifaddr)) 901 in6_ifaddr = ia->ia_next; 902 else { 903 while (ia->ia_next && (ia->ia_next != oia)) 904 ia = ia->ia_next; 905 if (ia->ia_next) 906 ia->ia_next = oia->ia_next; 907 else { 908 nd6log((LOG_ERR, 909 "%s: didn't unlink in6ifaddr from list\n", 910 if_name(ifp))); 911 } 912 } 913 914 IFAFREE(&oia->ia_ifa); 915 } 916 917 /* cleanup multicast address kludge table, if there is any */ 918 in6_purgemkludge(ifp); 919 920 /* 921 * remove neighbor management table. we call it twice just to make 922 * sure we nuke everything. maybe we need just one call. 923 * XXX: since the first call did not release addresses, some prefixes 924 * might remain. We should call nd6_purge() again to release the 925 * prefixes after removing all addresses above. 926 * (Or can we just delay calling nd6_purge until at this point?) 927 */ 928 nd6_purge(ifp); 929 } 930 931 int 932 in6_get_tmpifid(struct ifnet *ifp, u_int8_t *retbuf, 933 const u_int8_t *baseid, int generate) 934 { 935 u_int8_t nullbuf[8]; 936 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 937 938 memset(nullbuf, 0, sizeof(nullbuf)); 939 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) { 940 /* we've never created a random ID. Create a new one. */ 941 generate = 1; 942 } 943 944 if (generate) { 945 memcpy(ndi->randomseed1, baseid, sizeof(ndi->randomseed1)); 946 947 /* generate_tmp_ifid will update seedn and buf */ 948 (void)generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1, 949 ndi->randomid); 950 } 951 memcpy(retbuf, ndi->randomid, 8); 952 if (generate && memcmp(retbuf, nullbuf, sizeof(nullbuf)) == 0) { 953 /* generate_tmp_ifid could not found a good ID. */ 954 return -1; 955 } 956 957 return 0; 958 } 959 960 void 961 in6_tmpaddrtimer(void *ignored_arg) 962 { 963 struct nd_ifinfo *ndi; 964 u_int8_t nullbuf[8]; 965 struct ifnet *ifp; 966 967 mutex_enter(softnet_lock); 968 KERNEL_LOCK(1, NULL); 969 970 callout_reset(&in6_tmpaddrtimer_ch, 971 (ip6_temp_preferred_lifetime - ip6_desync_factor - 972 ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, NULL); 973 974 memset(nullbuf, 0, sizeof(nullbuf)); 975 TAILQ_FOREACH(ifp, &ifnet, if_list) { 976 ndi = ND_IFINFO(ifp); 977 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) { 978 /* 979 * We've been generating a random ID on this interface. 980 * Create a new one. 981 */ 982 (void)generate_tmp_ifid(ndi->randomseed0, 983 ndi->randomseed1, ndi->randomid); 984 } 985 } 986 987 KERNEL_UNLOCK_ONE(NULL); 988 mutex_exit(softnet_lock); 989 } 990