in6_ifattach.c revision 1.72
1 /* $NetBSD: in6_ifattach.c,v 1.72 2007/07/09 21:11:12 ad 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 1.72 2007/07/09 21:11:12 ad 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 __P((struct ifnet *, struct in6_addr *)); 71 #endif 72 static int get_rand_ifid __P((struct ifnet *, struct in6_addr *)); 73 static int generate_tmp_ifid __P((u_int8_t *, const u_int8_t *, u_int8_t *)); 74 static int get_ifid __P((struct ifnet *, struct ifnet *, struct in6_addr *)); 75 static int in6_ifattach_linklocal __P((struct ifnet *, struct ifnet *)); 76 static int in6_ifattach_loopback __P((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 struct sockaddr_dl *sdl; 328 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 TAILQ_FOREACH(ifa, &ifp->if_addrlist, ifa_list) { 335 if (ifa->ifa_addr->sa_family != AF_LINK) 336 continue; 337 sdl = (struct sockaddr_dl *)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 = LLADDR(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 ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6); 567 ifra.ifra_prefixmask.sin6_family = AF_INET6; 568 ifra.ifra_prefixmask.sin6_addr = in6mask64; 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 SIOCSIFADDR ioctl. I believe the 584 * notification is rather confusing in this case, so just 585 * suppress it. (jinmei (at) 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 ifra.ifra_prefixmask.sin6_len = sizeof(struct sockaddr_in6); 662 ifra.ifra_prefixmask.sin6_family = AF_INET6; 663 ifra.ifra_prefixmask.sin6_addr = in6mask128; 664 665 /* 666 * Always initialize ia_dstaddr (= broadcast address) to loopback 667 * address. Follows IPv4 practice - see in_ifinit(). 668 */ 669 ifra.ifra_dstaddr.sin6_len = sizeof(struct sockaddr_in6); 670 ifra.ifra_dstaddr.sin6_family = AF_INET6; 671 ifra.ifra_dstaddr.sin6_addr = in6addr_loopback; 672 673 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); 674 ifra.ifra_addr.sin6_family = AF_INET6; 675 ifra.ifra_addr.sin6_addr = in6addr_loopback; 676 677 /* the loopback address should NEVER expire. */ 678 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 679 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 680 681 /* we don't need to perform DAD on loopback interfaces. */ 682 ifra.ifra_flags |= IN6_IFF_NODAD; 683 684 /* 685 * We are sure that this is a newly assigned address, so we can set 686 * NULL to the 3rd arg. 687 */ 688 if ((error = in6_update_ifa(ifp, &ifra, NULL, 0)) != 0) { 689 nd6log((LOG_ERR, "in6_ifattach_loopback: failed to configure " 690 "the loopback address on %s (errno=%d)\n", 691 if_name(ifp), error)); 692 return -1; 693 } 694 695 return 0; 696 } 697 698 /* 699 * compute NI group address, based on the current hostname setting. 700 * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later). 701 * 702 * when ifp == NULL, the caller is responsible for filling scopeid. 703 */ 704 int 705 in6_nigroup(struct ifnet *ifp, const char *name, int namelen, 706 struct sockaddr_in6 *sa6) 707 { 708 const char *p; 709 u_int8_t *q; 710 MD5_CTX ctxt; 711 u_int8_t digest[16]; 712 u_int8_t l; 713 u_int8_t n[64]; /* a single label must not exceed 63 chars */ 714 715 if (!namelen || !name) 716 return -1; 717 718 p = name; 719 while (p && *p && *p != '.' && p - name < namelen) 720 p++; 721 if (p - name > sizeof(n) - 1) 722 return -1; /* label too long */ 723 l = p - name; 724 strncpy((char *)n, name, l); 725 n[(int)l] = '\0'; 726 for (q = n; *q; q++) { 727 if ('A' <= *q && *q <= 'Z') 728 *q = *q - 'A' + 'a'; 729 } 730 731 /* generate 8 bytes of pseudo-random value. */ 732 memset(&ctxt, 0, sizeof(ctxt)); 733 MD5Init(&ctxt); 734 MD5Update(&ctxt, &l, sizeof(l)); 735 MD5Update(&ctxt, n, l); 736 MD5Final(digest, &ctxt); 737 738 memset(sa6, 0, sizeof(*sa6)); 739 sa6->sin6_family = AF_INET6; 740 sa6->sin6_len = sizeof(*sa6); 741 sa6->sin6_addr.s6_addr16[0] = htons(0xff02); 742 sa6->sin6_addr.s6_addr8[11] = 2; 743 memcpy(&sa6->sin6_addr.s6_addr32[3], digest, 744 sizeof(sa6->sin6_addr.s6_addr32[3])); 745 if (in6_setscope(&sa6->sin6_addr, ifp, NULL)) 746 return -1; /* XXX: should not fail */ 747 748 return 0; 749 } 750 751 /* 752 * XXX multiple loopback interface needs more care. for instance, 753 * nodelocal address needs to be configured onto only one of them. 754 * XXX multiple link-local address case 755 * 756 * altifp - secondary EUI64 source 757 */ 758 void 759 in6_ifattach(struct ifnet *ifp, struct ifnet *altifp) 760 { 761 struct in6_ifaddr *ia; 762 struct in6_addr in6; 763 764 /* some of the interfaces are inherently not IPv6 capable */ 765 switch (ifp->if_type) { 766 case IFT_BRIDGE: 767 #ifdef IFT_PFLOG 768 case IFT_PFLOG: 769 #endif 770 #ifdef IFT_PFSYNC 771 case IFT_PFSYNC: 772 #endif 773 return; 774 } 775 776 /* 777 * if link mtu is too small, don't try to configure IPv6. 778 * remember there could be some link-layer that has special 779 * fragmentation logic. 780 */ 781 if (ifp->if_mtu < IPV6_MMTU) { 782 nd6log((LOG_INFO, "in6_ifattach: " 783 "%s has too small MTU, IPv6 not enabled\n", 784 if_name(ifp))); 785 return; 786 } 787 788 /* create a multicast kludge storage (if we have not had one) */ 789 in6_createmkludge(ifp); 790 791 /* 792 * quirks based on interface type 793 */ 794 switch (ifp->if_type) { 795 #ifdef IFT_STF 796 case IFT_STF: 797 /* 798 * 6to4 interface is a very special kind of beast. 799 * no multicast, no linklocal. RFC2529 specifies how to make 800 * linklocals for 6to4 interface, but there's no use and 801 * it is rather harmful to have one. 802 */ 803 return; 804 #endif 805 case IFT_CARP: 806 return; 807 default: 808 break; 809 } 810 811 /* 812 * usually, we require multicast capability to the interface 813 */ 814 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 815 nd6log((LOG_INFO, "in6_ifattach: " 816 "%s is not multicast capable, IPv6 not enabled\n", 817 if_name(ifp))); 818 return; 819 } 820 821 /* 822 * assign loopback address for loopback interface. 823 * XXX multiple loopback interface case. 824 */ 825 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 826 in6 = in6addr_loopback; 827 if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) { 828 if (in6_ifattach_loopback(ifp) != 0) 829 return; 830 } 831 } 832 833 /* 834 * assign a link-local address, if there's none. 835 */ 836 if (ip6_auto_linklocal) { 837 ia = in6ifa_ifpforlinklocal(ifp, 0); 838 if (ia == NULL && in6_ifattach_linklocal(ifp, altifp) != 0) { 839 printf("%s: cannot assign link-local address\n", 840 ifp->if_xname); 841 } 842 } 843 } 844 845 /* 846 * NOTE: in6_ifdetach() does not support loopback if at this moment. 847 * We don't need this function in bsdi, because interfaces are never removed 848 * from the ifnet list in bsdi. 849 */ 850 void 851 in6_ifdetach(struct ifnet *ifp) 852 { 853 struct in6_ifaddr *ia, *oia; 854 struct ifaddr *ifa, *next; 855 struct rtentry *rt; 856 short rtflags; 857 struct in6_multi_mship *imm; 858 859 /* remove ip6_mrouter stuff */ 860 ip6_mrouter_detach(ifp); 861 862 /* remove neighbor management table */ 863 nd6_purge(ifp); 864 865 /* nuke any of IPv6 addresses we have */ 866 for (ifa = TAILQ_FIRST(&ifp->if_addrlist); ifa; ifa = next) { 867 next = TAILQ_NEXT(ifa, ifa_list); 868 if (ifa->ifa_addr->sa_family != AF_INET6) 869 continue; 870 in6_purgeaddr(ifa); 871 } 872 873 /* undo everything done by in6_ifattach(), just in case */ 874 for (ifa = TAILQ_FIRST(&ifp->if_addrlist); ifa; ifa = next) { 875 next = TAILQ_NEXT(ifa, ifa_list); 876 877 if (ifa->ifa_addr->sa_family != AF_INET6 878 || !IN6_IS_ADDR_LINKLOCAL(&satosin6(&ifa->ifa_addr)->sin6_addr)) { 879 continue; 880 } 881 882 ia = (struct in6_ifaddr *)ifa; 883 884 /* 885 * leave from multicast groups we have joined for the interface 886 */ 887 while ((imm = LIST_FIRST(&ia->ia6_memberships)) != NULL) { 888 LIST_REMOVE(imm, i6mm_chain); 889 in6_leavegroup(imm); 890 } 891 892 /* remove from the routing table */ 893 if ((ia->ia_flags & IFA_ROUTE) && 894 (rt = rtalloc1((struct sockaddr *)&ia->ia_addr, 0))) { 895 rtflags = rt->rt_flags; 896 rtfree(rt); 897 rtrequest(RTM_DELETE, (struct sockaddr *)&ia->ia_addr, 898 (struct sockaddr *)&ia->ia_addr, 899 (struct sockaddr *)&ia->ia_prefixmask, 900 rtflags, (struct rtentry **)0); 901 } 902 903 /* remove from the linked list */ 904 TAILQ_REMOVE(&ifp->if_addrlist, &ia->ia_ifa, ifa_list); 905 IFAFREE(&ia->ia_ifa); 906 907 /* also remove from the IPv6 address chain(itojun&jinmei) */ 908 oia = ia; 909 if (oia == (ia = in6_ifaddr)) 910 in6_ifaddr = ia->ia_next; 911 else { 912 while (ia->ia_next && (ia->ia_next != oia)) 913 ia = ia->ia_next; 914 if (ia->ia_next) 915 ia->ia_next = oia->ia_next; 916 else { 917 nd6log((LOG_ERR, 918 "%s: didn't unlink in6ifaddr from list\n", 919 if_name(ifp))); 920 } 921 } 922 923 IFAFREE(&oia->ia_ifa); 924 } 925 926 /* cleanup multicast address kludge table, if there is any */ 927 in6_purgemkludge(ifp); 928 929 /* 930 * remove neighbor management table. we call it twice just to make 931 * sure we nuke everything. maybe we need just one call. 932 * XXX: since the first call did not release addresses, some prefixes 933 * might remain. We should call nd6_purge() again to release the 934 * prefixes after removing all addresses above. 935 * (Or can we just delay calling nd6_purge until at this point?) 936 */ 937 nd6_purge(ifp); 938 } 939 940 int 941 in6_get_tmpifid(struct ifnet *ifp, u_int8_t *retbuf, 942 const u_int8_t *baseid, int generate) 943 { 944 u_int8_t nullbuf[8]; 945 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 946 947 memset(nullbuf, 0, sizeof(nullbuf)); 948 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) { 949 /* we've never created a random ID. Create a new one. */ 950 generate = 1; 951 } 952 953 if (generate) { 954 memcpy(ndi->randomseed1, baseid, sizeof(ndi->randomseed1)); 955 956 /* generate_tmp_ifid will update seedn and buf */ 957 (void)generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1, 958 ndi->randomid); 959 } 960 memcpy(retbuf, ndi->randomid, 8); 961 if (generate && memcmp(retbuf, nullbuf, sizeof(nullbuf)) == 0) { 962 /* generate_tmp_ifid could not found a good ID. */ 963 return -1; 964 } 965 966 return 0; 967 } 968 969 void 970 in6_tmpaddrtimer(void *ignored_arg) 971 { 972 struct nd_ifinfo *ndi; 973 u_int8_t nullbuf[8]; 974 struct ifnet *ifp; 975 int s = splsoftnet(); 976 977 callout_reset(&in6_tmpaddrtimer_ch, 978 (ip6_temp_preferred_lifetime - ip6_desync_factor - 979 ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, NULL); 980 981 memset(nullbuf, 0, sizeof(nullbuf)); 982 TAILQ_FOREACH(ifp, &ifnet, if_list) { 983 ndi = ND_IFINFO(ifp); 984 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) { 985 /* 986 * We've been generating a random ID on this interface. 987 * Create a new one. 988 */ 989 (void)generate_tmp_ifid(ndi->randomseed0, 990 ndi->randomseed1, ndi->randomid); 991 } 992 } 993 994 splx(s); 995 } 996
Indexes created Fri Sep 26 20:09:58 GMT 2025