1 /* $NetBSD: in6_ifattach.c,v 1.105 2016/08/16 10:31:57 roy 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 1.105 2016/08/16 10:31:57 roy Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/kmem.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 #include <sys/socketvar.h> 45 #include <sys/cprng.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 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 in6_addr *in6) /* upper 64bits are preserved */ 145 { 146 MD5_CTX ctxt; 147 u_int8_t digest[16]; 148 149 #if 0 150 /* we need at least several letters as seed for ifid */ 151 if (hostnamelen < 3) 152 return -1; 153 #endif 154 155 /* generate 8 bytes of pseudo-random value. */ 156 memset(&ctxt, 0, sizeof(ctxt)); 157 MD5Init(&ctxt); 158 MD5Update(&ctxt, (u_char *)hostname, hostnamelen); 159 MD5Final(digest, &ctxt); 160 161 /* assumes sizeof(digest) > sizeof(ifid) */ 162 memcpy(&in6->s6_addr[8], digest, 8); 163 164 /* make sure to set "u" bit to local, and "g" bit to individual. */ 165 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 166 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 167 168 /* convert EUI64 into IPv6 interface identifier */ 169 EUI64_TO_IFID(in6); 170 171 return 0; 172 } 173 174 static int 175 generate_tmp_ifid(u_int8_t *seed0, const u_int8_t *seed1, u_int8_t *ret) 176 { 177 MD5_CTX ctxt; 178 u_int8_t seed[16], digest[16], nullbuf[8]; 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 cprng_fast(seed, sizeof(seed)); 193 } else 194 memcpy(seed, seed0, 8); 195 196 /* copy the right-most 64-bits of the given address */ 197 /* XXX assumption on the size of IFID */ 198 memcpy(&seed[8], seed1, 8); 199 200 again: 201 /* for debugging purposes only */ 202 #if 0 203 { 204 int i; 205 206 printf("generate_tmp_ifid: new randomized ID from: "); 207 for (i = 0; i < 16; i++) 208 printf("%02x", seed[i]); 209 printf(" "); 210 } 211 #endif 212 213 /* generate 16 bytes of pseudo-random value. */ 214 memset(&ctxt, 0, sizeof(ctxt)); 215 MD5Init(&ctxt); 216 MD5Update(&ctxt, seed, sizeof(seed)); 217 MD5Final(digest, &ctxt); 218 219 /* 220 * draft-ietf-ipngwg-temp-addresses-v2-00.txt 3.2.1. (3) 221 * Take the left-most 64-bits of the MD5 digest and set bit 6 (the 222 * left-most bit is numbered 0) to zero. 223 */ 224 memcpy(ret, digest, 8); 225 ret[0] &= ~EUI64_UBIT; 226 227 /* 228 * Reject inappropriate identifiers according to 229 * draft-ietf-ipngwg-temp-addresses-v2-00.txt 3.2.1. (4) 230 * At this moment, we reject following cases: 231 * - all 0 identifier 232 * - identifiers that conflict with reserved subnet anycast addresses, 233 * which are defined in RFC 2526. 234 * - identifiers that conflict with ISATAP addresses 235 * - identifiers used in our own addresses 236 */ 237 badid = 0; 238 if (memcmp(nullbuf, ret, sizeof(nullbuf)) == 0) 239 badid = 1; 240 else if (memcmp(anycast_id, ret, 7) == 0 && 241 (anycast_id[7] & ret[7]) == anycast_id[7]) { 242 badid = 1; 243 } else if (memcmp(isatap_id, ret, sizeof(isatap_id)) == 0) 244 badid = 1; 245 else { 246 struct in6_ifaddr *ia; 247 int s = pserialize_read_enter(); 248 249 IN6_ADDRLIST_READER_FOREACH(ia) { 250 if (!memcmp(&ia->ia_addr.sin6_addr.s6_addr[8], 251 ret, 8)) { 252 badid = 1; 253 break; 254 } 255 } 256 pserialize_read_exit(s); 257 } 258 259 /* 260 * In the event that an unacceptable identifier has been generated, 261 * restart the process, using the right-most 64 bits of the MD5 digest 262 * obtained in place of the history value. 263 */ 264 if (badid) { 265 /* for debugging purposes only */ 266 #if 0 267 { 268 int i; 269 270 printf("unacceptable random ID: "); 271 for (i = 0; i < 16; i++) 272 printf("%02x", digest[i]); 273 printf("\n"); 274 } 275 #endif 276 277 if (++retry < GEN_TEMPID_RETRY_MAX) { 278 memcpy(seed, &digest[8], 8); 279 goto again; 280 } else { 281 /* 282 * We're so unlucky. Give up for now, and return 283 * all 0 IDs to tell the caller not to make a 284 * temporary address. 285 */ 286 nd6log(LOG_NOTICE, "never found a good ID\n"); 287 memset(ret, 0, 8); 288 } 289 } 290 291 /* 292 * draft-ietf-ipngwg-temp-addresses-v2-00.txt 3.2.1. (6) 293 * Take the rightmost 64-bits of the MD5 digest and save them in 294 * stable storage as the history value to be used in the next 295 * iteration of the algorithm. 296 */ 297 memcpy(seed0, &digest[8], 8); 298 299 /* for debugging purposes only */ 300 #if 0 301 { 302 int i; 303 304 printf("to: "); 305 for (i = 0; i < 16; i++) 306 printf("%02x", digest[i]); 307 printf("\n"); 308 } 309 #endif 310 311 return 0; 312 } 313 314 /* 315 * Get interface identifier for the specified interface. 316 * 317 * in6 - upper 64bits are preserved 318 */ 319 int 320 in6_get_hw_ifid(struct ifnet *ifp, struct in6_addr *in6) 321 { 322 struct ifaddr *ifa; 323 const struct sockaddr_dl *sdl = NULL; 324 const char *addr = NULL; /* XXX gcc 4.8 -Werror=maybe-uninitialized */ 325 size_t addrlen = 0; /* XXX gcc 4.8 -Werror=maybe-uninitialized */ 326 static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; 327 static u_int8_t allone[8] = 328 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 329 int s; 330 331 s = pserialize_read_enter(); 332 IFADDR_READER_FOREACH(ifa, ifp) { 333 const struct sockaddr_dl *tsdl; 334 if (ifa->ifa_addr->sa_family != AF_LINK) 335 continue; 336 tsdl = satocsdl(ifa->ifa_addr); 337 if (tsdl == NULL || tsdl->sdl_alen == 0) 338 continue; 339 if (sdl == NULL || ifa == ifp->if_dl || ifa == ifp->if_hwdl) { 340 sdl = tsdl; 341 addr = CLLADDR(sdl); 342 addrlen = sdl->sdl_alen; 343 } 344 if (ifa == ifp->if_hwdl) 345 break; 346 } 347 pserialize_read_exit(s); 348 349 if (sdl == NULL) 350 return -1; 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 int s; 464 465 /* first, try to get it from the interface itself */ 466 if (in6_get_hw_ifid(ifp0, in6) == 0) { 467 nd6log(LOG_DEBUG, "%s: got interface identifier from itself\n", 468 if_name(ifp0)); 469 goto success; 470 } 471 472 /* try secondary EUI64 source. this basically is for ATM PVC */ 473 if (altifp && in6_get_hw_ifid(altifp, in6) == 0) { 474 nd6log(LOG_DEBUG, "%s: got interface identifier from %s\n", 475 if_name(ifp0), if_name(altifp)); 476 goto success; 477 } 478 479 /* next, try to get it from some other hardware interface */ 480 s = pserialize_read_enter(); 481 IFNET_READER_FOREACH(ifp) { 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 pserialize_read_exit(s); 499 500 #if 0 501 /* get from hostid - only for certain architectures */ 502 if (get_hostid_ifid(ifp, in6) == 0) { 503 nd6log(LOG_DEBUG, 504 "%s: interface identifier generated by hostid\n", 505 if_name(ifp0)); 506 goto success; 507 } 508 #endif 509 510 /* last resort: get from random number source */ 511 if (get_rand_ifid(in6) == 0) { 512 nd6log(LOG_DEBUG, 513 "%s: interface identifier generated by random number\n", 514 if_name(ifp0)); 515 goto success; 516 } 517 518 printf("%s: failed to get interface identifier\n", if_name(ifp0)); 519 return -1; 520 521 success: 522 nd6log(LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n", 523 if_name(ifp0), in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10], 524 in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13], 525 in6->s6_addr[14], in6->s6_addr[15]); 526 return 0; 527 } 528 529 /* 530 * altifp - secondary EUI64 source 531 */ 532 533 static int 534 in6_ifattach_linklocal(struct ifnet *ifp, struct ifnet *altifp) 535 { 536 struct in6_aliasreq ifra; 537 int error; 538 539 /* 540 * configure link-local address. 541 */ 542 memset(&ifra, 0, sizeof(ifra)); 543 544 /* 545 * in6_update_ifa() does not use ifra_name, but we accurately set it 546 * for safety. 547 */ 548 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 549 550 ifra.ifra_addr.sin6_family = AF_INET6; 551 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); 552 ifra.ifra_addr.sin6_addr.s6_addr32[0] = htonl(0xfe800000); 553 ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0; 554 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 555 ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0; 556 ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1); 557 } else { 558 if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) { 559 nd6log(LOG_ERR, 560 "%s: no ifid available\n", if_name(ifp)); 561 return -1; 562 } 563 } 564 if (in6_setscope(&ifra.ifra_addr.sin6_addr, ifp, NULL)) 565 return -1; 566 567 sockaddr_in6_init(&ifra.ifra_prefixmask, &in6mask64, 0, 0, 0); 568 /* link-local addresses should NEVER expire. */ 569 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 570 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 571 572 /* 573 * Now call in6_update_ifa() to do a bunch of procedures to configure 574 * a link-local address. We can set the 3rd argument to NULL, because 575 * we know there's no other link-local address on the interface 576 * and therefore we are adding one (instead of updating one). 577 */ 578 if ((error = in6_update_ifa(ifp, &ifra, NULL, 579 IN6_IFAUPDATE_DADDELAY)) != 0) { 580 /* 581 * XXX: When the interface does not support IPv6, this call 582 * would fail in the SIOCINITIFADDR ioctl. I believe the 583 * notification is rather confusing in this case, so just 584 * suppress it. (jinmei@kame.net 20010130) 585 */ 586 if (error != EAFNOSUPPORT) 587 nd6log(LOG_NOTICE, 588 "failed to configure a link-local address on %s " 589 "(errno=%d)\n", 590 if_name(ifp), error); 591 return -1; 592 } 593 594 return 0; 595 } 596 597 /* 598 * ifp - mut be IFT_LOOP 599 */ 600 601 static int 602 in6_ifattach_loopback(struct ifnet *ifp) 603 { 604 struct in6_aliasreq ifra; 605 int error; 606 607 memset(&ifra, 0, sizeof(ifra)); 608 609 /* 610 * in6_update_ifa() does not use ifra_name, but we accurately set it 611 * for safety. 612 */ 613 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 614 615 sockaddr_in6_init(&ifra.ifra_prefixmask, &in6mask128, 0, 0, 0); 616 617 /* 618 * Always initialize ia_dstaddr (= broadcast address) to loopback 619 * address. Follows IPv4 practice - see in_ifinit(). 620 */ 621 sockaddr_in6_init(&ifra.ifra_dstaddr, &in6addr_loopback, 0, 0, 0); 622 623 sockaddr_in6_init(&ifra.ifra_addr, &in6addr_loopback, 0, 0, 0); 624 625 /* the loopback address should NEVER expire. */ 626 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 627 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 628 629 /* we don't need to perform DAD on loopback interfaces. */ 630 ifra.ifra_flags |= IN6_IFF_NODAD; 631 632 /* 633 * We are sure that this is a newly assigned address, so we can set 634 * NULL to the 3rd arg. 635 */ 636 if ((error = in6_update_ifa(ifp, &ifra, NULL, 0)) != 0) { 637 nd6log(LOG_ERR, "failed to configure " 638 "the loopback address on %s (errno=%d)\n", 639 if_name(ifp), error); 640 return -1; 641 } 642 643 return 0; 644 } 645 646 /* 647 * compute NI group address, based on the current hostname setting. 648 * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later). 649 * 650 * when ifp == NULL, the caller is responsible for filling scopeid. 651 */ 652 int 653 in6_nigroup(struct ifnet *ifp, const char *name, int namelen, 654 struct sockaddr_in6 *sa6) 655 { 656 const char *p; 657 u_int8_t *q; 658 MD5_CTX ctxt; 659 u_int8_t digest[16]; 660 u_int8_t l; 661 u_int8_t n[64]; /* a single label must not exceed 63 chars */ 662 663 if (!namelen || !name) 664 return -1; 665 666 p = name; 667 while (p && *p && *p != '.' && p - name < namelen) 668 p++; 669 if (p - name > sizeof(n) - 1) 670 return -1; /* label too long */ 671 l = p - name; 672 strncpy((char *)n, name, l); 673 n[(int)l] = '\0'; 674 for (q = n; *q; q++) { 675 if ('A' <= *q && *q <= 'Z') 676 *q = *q - 'A' + 'a'; 677 } 678 679 /* generate 8 bytes of pseudo-random value. */ 680 memset(&ctxt, 0, sizeof(ctxt)); 681 MD5Init(&ctxt); 682 MD5Update(&ctxt, &l, sizeof(l)); 683 MD5Update(&ctxt, n, l); 684 MD5Final(digest, &ctxt); 685 686 memset(sa6, 0, sizeof(*sa6)); 687 sa6->sin6_family = AF_INET6; 688 sa6->sin6_len = sizeof(*sa6); 689 sa6->sin6_addr.s6_addr16[0] = htons(0xff02); 690 sa6->sin6_addr.s6_addr8[11] = 2; 691 memcpy(&sa6->sin6_addr.s6_addr32[3], digest, 692 sizeof(sa6->sin6_addr.s6_addr32[3])); 693 if (in6_setscope(&sa6->sin6_addr, ifp, NULL)) 694 return -1; /* XXX: should not fail */ 695 696 return 0; 697 } 698 699 /* 700 * XXX multiple loopback interface needs more care. for instance, 701 * nodelocal address needs to be configured onto only one of them. 702 * XXX multiple link-local address case 703 * 704 * altifp - secondary EUI64 source 705 */ 706 void 707 in6_ifattach(struct ifnet *ifp, struct ifnet *altifp) 708 { 709 struct in6_ifaddr *ia; 710 struct in6_addr in6; 711 712 /* some of the interfaces are inherently not IPv6 capable */ 713 switch (ifp->if_type) { 714 case IFT_BRIDGE: 715 #ifdef IFT_PFLOG 716 case IFT_PFLOG: 717 #endif 718 #ifdef IFT_PFSYNC 719 case IFT_PFSYNC: 720 #endif 721 ND_IFINFO(ifp)->flags &= ~ND6_IFF_AUTO_LINKLOCAL; 722 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 723 return; 724 } 725 726 /* 727 * if link mtu is too small, don't try to configure IPv6. 728 * remember there could be some link-layer that has special 729 * fragmentation logic. 730 */ 731 if (ifp->if_mtu < IPV6_MMTU) { 732 nd6log(LOG_INFO, "%s has too small MTU, IPv6 not enabled\n", 733 if_name(ifp)); 734 return; 735 } 736 737 /* create a multicast kludge storage (if we have not had one) */ 738 in6_createmkludge(ifp); 739 740 /* 741 * quirks based on interface type 742 */ 743 switch (ifp->if_type) { 744 #ifdef IFT_STF 745 case IFT_STF: 746 /* 747 * 6to4 interface is a very special kind of beast. 748 * no multicast, no linklocal. RFC2529 specifies how to make 749 * linklocals for 6to4 interface, but there's no use and 750 * it is rather harmful to have one. 751 */ 752 ND_IFINFO(ifp)->flags &= ~ND6_IFF_AUTO_LINKLOCAL; 753 return; 754 #endif 755 case IFT_CARP: 756 return; 757 default: 758 break; 759 } 760 761 /* 762 * usually, we require multicast capability to the interface 763 */ 764 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 765 nd6log(LOG_INFO, 766 "%s is not multicast capable, IPv6 not enabled\n", 767 if_name(ifp)); 768 return; 769 } 770 771 /* 772 * assign loopback address for loopback interface. 773 * XXX multiple loopback interface case. 774 */ 775 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 776 int s = pserialize_read_enter(); 777 in6 = in6addr_loopback; 778 if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) { 779 if (in6_ifattach_loopback(ifp) != 0) { 780 pserialize_read_exit(s); 781 return; 782 } 783 } 784 pserialize_read_exit(s); 785 } 786 787 /* 788 * assign a link-local address, if there's none. 789 */ 790 if (!(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) && 791 ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL) { 792 int s = pserialize_read_enter(); 793 ia = in6ifa_ifpforlinklocal(ifp, 0); 794 if (ia == NULL && in6_ifattach_linklocal(ifp, altifp) != 0) { 795 printf("%s: cannot assign link-local address\n", 796 ifp->if_xname); 797 } 798 pserialize_read_exit(s); 799 } 800 } 801 802 /* 803 * NOTE: in6_ifdetach() does not support loopback if at this moment. 804 * We don't need this function in bsdi, because interfaces are never removed 805 * from the ifnet list in bsdi. 806 */ 807 void 808 in6_ifdetach(struct ifnet *ifp) 809 { 810 811 /* remove ip6_mrouter stuff */ 812 ip6_mrouter_detach(ifp); 813 814 /* remove neighbor management table */ 815 nd6_purge(ifp, NULL); 816 817 /* nuke any of IPv6 addresses we have */ 818 if_purgeaddrs(ifp, AF_INET6, in6_purgeaddr); 819 820 /* cleanup multicast address kludge table, if there is any */ 821 in6_purgemkludge(ifp); 822 823 /* 824 * remove neighbor management table. we call it twice just to make 825 * sure we nuke everything. maybe we need just one call. 826 * XXX: since the first call did not release addresses, some prefixes 827 * might remain. We should call nd6_purge() again to release the 828 * prefixes after removing all addresses above. 829 * (Or can we just delay calling nd6_purge until at this point?) 830 */ 831 nd6_purge(ifp, NULL); 832 } 833 834 int 835 in6_get_tmpifid(struct ifnet *ifp, u_int8_t *retbuf, 836 const u_int8_t *baseid, int generate) 837 { 838 u_int8_t nullbuf[8]; 839 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 840 841 memset(nullbuf, 0, sizeof(nullbuf)); 842 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) { 843 /* we've never created a random ID. Create a new one. */ 844 generate = 1; 845 } 846 847 if (generate) { 848 memcpy(ndi->randomseed1, baseid, sizeof(ndi->randomseed1)); 849 850 /* generate_tmp_ifid will update seedn and buf */ 851 (void)generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1, 852 ndi->randomid); 853 } 854 memcpy(retbuf, ndi->randomid, 8); 855 if (generate && memcmp(retbuf, nullbuf, sizeof(nullbuf)) == 0) { 856 /* generate_tmp_ifid could not found a good ID. */ 857 return -1; 858 } 859 860 return 0; 861 } 862 863 void 864 in6_tmpaddrtimer(void *ignored_arg) 865 { 866 struct nd_ifinfo *ndi; 867 u_int8_t nullbuf[8]; 868 struct ifnet *ifp; 869 int s; 870 871 mutex_enter(softnet_lock); 872 KERNEL_LOCK(1, NULL); 873 874 callout_reset(&in6_tmpaddrtimer_ch, 875 (ip6_temp_preferred_lifetime - ip6_desync_factor - 876 ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, NULL); 877 878 memset(nullbuf, 0, sizeof(nullbuf)); 879 s = pserialize_read_enter(); 880 IFNET_READER_FOREACH(ifp) { 881 ndi = ND_IFINFO(ifp); 882 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) { 883 /* 884 * We've been generating a random ID on this interface. 885 * Create a new one. 886 */ 887 (void)generate_tmp_ifid(ndi->randomseed0, 888 ndi->randomseed1, ndi->randomid); 889 } 890 } 891 pserialize_read_exit(s); 892 893 KERNEL_UNLOCK_ONE(NULL); 894 mutex_exit(softnet_lock); 895 } 896