1 /* $NetBSD: in6_ifattach.c,v 1.118 2020/01/20 18:38:22 thorpej 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 1.118 2020/01/20 18:38:22 thorpej 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 unsigned long in6_maxmtu = 0; 63 64 int ip6_auto_linklocal = 1; /* enable by default */ 65 66 static 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 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 static void in6_tmpaddrtimer(void *); 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_ATM: 368 case IFT_IEEE1394: 369 case IFT_IEEE80211: 370 /* look at IEEE802/EUI64 only */ 371 if (addrlen != 8 && addrlen != 6) 372 return -1; 373 374 /* 375 * check for invalid MAC address - on bsdi, we see it a lot 376 * since wildboar configures all-zero MAC on pccard before 377 * card insertion. 378 */ 379 if (memcmp(addr, allzero, addrlen) == 0) 380 return -1; 381 if (memcmp(addr, allone, addrlen) == 0) 382 return -1; 383 384 /* make EUI64 address */ 385 if (addrlen == 8) 386 memcpy(&in6->s6_addr[8], addr, 8); 387 else if (addrlen == 6) { 388 in6->s6_addr[8] = addr[0]; 389 in6->s6_addr[9] = addr[1]; 390 in6->s6_addr[10] = addr[2]; 391 in6->s6_addr[11] = 0xff; 392 in6->s6_addr[12] = 0xfe; 393 in6->s6_addr[13] = addr[3]; 394 in6->s6_addr[14] = addr[4]; 395 in6->s6_addr[15] = addr[5]; 396 } 397 break; 398 399 case IFT_ARCNET: 400 if (addrlen != 1) 401 return -1; 402 if (!addr[0]) 403 return -1; 404 405 memset(&in6->s6_addr[8], 0, 8); 406 in6->s6_addr[15] = addr[0]; 407 408 /* 409 * due to insufficient bitwidth, we mark it local. 410 */ 411 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 412 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 413 break; 414 415 case IFT_GIF: 416 #ifdef IFT_STF 417 case IFT_STF: 418 #endif 419 /* 420 * RFC2893 says: "SHOULD use IPv4 address as ifid source". 421 * however, IPv4 address is not very suitable as unique 422 * identifier source (can be renumbered). 423 * we don't do this. 424 */ 425 return -1; 426 427 default: 428 return -1; 429 } 430 431 /* sanity check: g bit must not indicate "group" */ 432 if (EUI64_GROUP(in6)) 433 return -1; 434 435 /* convert EUI64 into IPv6 interface identifier */ 436 EUI64_TO_IFID(in6); 437 438 /* 439 * sanity check: ifid must not be all zero, avoid conflict with 440 * subnet router anycast 441 */ 442 if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 && 443 memcmp(&in6->s6_addr[9], allzero, 7) == 0) { 444 return -1; 445 } 446 447 return 0; 448 } 449 450 /* 451 * Get interface identifier for the specified interface. If it is not 452 * available on ifp0, borrow interface identifier from other information 453 * sources. 454 * 455 * altifp - secondary EUI64 source 456 */ 457 static int 458 get_ifid(struct ifnet *ifp0, struct ifnet *altifp, 459 struct in6_addr *in6) 460 { 461 struct ifnet *ifp; 462 int s; 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 s = pserialize_read_enter(); 480 IFNET_READER_FOREACH(ifp) { 481 if (ifp == ifp0) 482 continue; 483 if (in6_get_hw_ifid(ifp, in6) != 0) 484 continue; 485 486 /* 487 * to borrow ifid from other interface, ifid needs to be 488 * globally unique 489 */ 490 if (IFID_UNIVERSAL(in6)) { 491 nd6log(LOG_DEBUG, 492 "%s: borrow interface identifier from %s\n", 493 if_name(ifp0), if_name(ifp)); 494 pserialize_read_exit(s); 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, IN6_IFAUPDATE_DADDELAY)) != 0) { 579 /* 580 * XXX: When the interface does not support IPv6, this call 581 * would fail in the SIOCINITIFADDR 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, 587 "failed to configure a link-local address on %s " 588 "(errno=%d)\n", 589 if_name(ifp), error); 590 return -1; 591 } 592 593 return 0; 594 } 595 596 /* 597 * ifp - mut be IFT_LOOP 598 */ 599 600 static int 601 in6_ifattach_loopback(struct ifnet *ifp) 602 { 603 struct in6_aliasreq ifra; 604 int error; 605 606 memset(&ifra, 0, sizeof(ifra)); 607 608 /* 609 * in6_update_ifa() does not use ifra_name, but we accurately set it 610 * for safety. 611 */ 612 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 613 614 sockaddr_in6_init(&ifra.ifra_prefixmask, &in6mask128, 0, 0, 0); 615 616 /* 617 * Always initialize ia_dstaddr (= broadcast address) to loopback 618 * address. Follows IPv4 practice - see in_ifinit(). 619 */ 620 sockaddr_in6_init(&ifra.ifra_dstaddr, &in6addr_loopback, 0, 0, 0); 621 622 sockaddr_in6_init(&ifra.ifra_addr, &in6addr_loopback, 0, 0, 0); 623 624 /* the loopback address should NEVER expire. */ 625 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 626 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 627 628 /* we don't need to perform DAD on loopback interfaces. */ 629 ifra.ifra_flags |= IN6_IFF_NODAD; 630 631 /* 632 * We are sure that this is a newly assigned address, so we can set 633 * NULL to the 3rd arg. 634 */ 635 if ((error = in6_update_ifa(ifp, &ifra, 0)) != 0) { 636 nd6log(LOG_ERR, "failed to configure " 637 "the loopback address on %s (errno=%d)\n", 638 if_name(ifp), error); 639 return -1; 640 } 641 642 return 0; 643 } 644 645 /* 646 * compute NI group address, based on the current hostname setting. 647 * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later). 648 * 649 * when ifp == NULL, the caller is responsible for filling scopeid. 650 */ 651 int 652 in6_nigroup(struct ifnet *ifp, const char *name, int namelen, 653 struct sockaddr_in6 *sa6) 654 { 655 const char *p; 656 u_int8_t *q; 657 MD5_CTX ctxt; 658 u_int8_t digest[16]; 659 u_int8_t l; 660 u_int8_t n[64]; /* a single label must not exceed 63 chars */ 661 662 if (!namelen || !name) 663 return -1; 664 665 p = name; 666 while (p && *p && *p != '.' && p - name < namelen) 667 p++; 668 if (p - name > sizeof(n) - 1) 669 return -1; /* label too long */ 670 l = p - name; 671 strncpy((char *)n, name, l); 672 n[(int)l] = '\0'; 673 for (q = n; *q; q++) { 674 if ('A' <= *q && *q <= 'Z') 675 *q = *q - 'A' + 'a'; 676 } 677 678 /* generate 8 bytes of pseudo-random value. */ 679 memset(&ctxt, 0, sizeof(ctxt)); 680 MD5Init(&ctxt); 681 MD5Update(&ctxt, &l, sizeof(l)); 682 MD5Update(&ctxt, n, l); 683 MD5Final(digest, &ctxt); 684 685 memset(sa6, 0, sizeof(*sa6)); 686 sa6->sin6_family = AF_INET6; 687 sa6->sin6_len = sizeof(*sa6); 688 sa6->sin6_addr.s6_addr16[0] = htons(0xff02); 689 sa6->sin6_addr.s6_addr8[11] = 2; 690 memcpy(&sa6->sin6_addr.s6_addr32[3], digest, 691 sizeof(sa6->sin6_addr.s6_addr32[3])); 692 if (in6_setscope(&sa6->sin6_addr, ifp, NULL)) 693 return -1; /* XXX: should not fail */ 694 695 return 0; 696 } 697 698 /* 699 * XXX multiple loopback interface needs more care. for instance, 700 * nodelocal address needs to be configured onto only one of them. 701 * XXX multiple link-local address case 702 * 703 * altifp - secondary EUI64 source 704 */ 705 void 706 in6_ifattach(struct ifnet *ifp, struct ifnet *altifp) 707 { 708 struct in6_ifaddr *ia; 709 struct in6_addr in6; 710 711 KASSERT(IFNET_LOCKED(ifp)); 712 713 /* some of the interfaces are inherently not IPv6 capable */ 714 switch (ifp->if_type) { 715 case IFT_BRIDGE: 716 case IFT_L2TP: 717 #ifdef IFT_PFLOG 718 case IFT_PFLOG: 719 #endif 720 #ifdef IFT_PFSYNC 721 case IFT_PFSYNC: 722 #endif 723 ND_IFINFO(ifp)->flags &= ~ND6_IFF_AUTO_LINKLOCAL; 724 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 725 return; 726 } 727 728 /* 729 * if link mtu is too small, don't try to configure IPv6. 730 * remember there could be some link-layer that has special 731 * fragmentation logic. 732 */ 733 if (ifp->if_mtu < IPV6_MMTU) { 734 nd6log(LOG_INFO, "%s has too small MTU, IPv6 not enabled\n", 735 if_name(ifp)); 736 return; 737 } 738 739 /* 740 * quirks based on interface type 741 */ 742 switch (ifp->if_type) { 743 #ifdef IFT_STF 744 case IFT_STF: 745 /* 746 * 6to4 interface is a very special kind of beast. 747 * no multicast, no linklocal. RFC2529 specifies how to make 748 * linklocals for 6to4 interface, but there's no use and 749 * it is rather harmful to have one. 750 */ 751 ND_IFINFO(ifp)->flags &= ~ND6_IFF_AUTO_LINKLOCAL; 752 return; 753 #endif 754 case IFT_CARP: 755 return; 756 default: 757 break; 758 } 759 760 /* 761 * usually, we require multicast capability to the interface 762 */ 763 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 764 nd6log(LOG_INFO, 765 "%s is not multicast capable, IPv6 not enabled\n", 766 if_name(ifp)); 767 return; 768 } 769 770 /* 771 * assign loopback address for loopback interface. 772 * XXX multiple loopback interface case. 773 */ 774 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 775 in6 = in6addr_loopback; 776 /* These are safe and atomic thanks to IFNET_LOCK */ 777 if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) { 778 if (in6_ifattach_loopback(ifp) != 0) 779 return; 780 } 781 } 782 783 /* 784 * assign a link-local address, if there's none. 785 */ 786 if (!(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) && 787 ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL) { 788 int bound = curlwp_bind(); 789 struct psref psref; 790 ia = in6ifa_ifpforlinklocal_psref(ifp, 0, &psref); 791 if (ia == NULL && in6_ifattach_linklocal(ifp, altifp) != 0) { 792 printf("%s: cannot assign link-local address\n", 793 ifp->if_xname); 794 } 795 ia6_release(ia, &psref); 796 curlwp_bindx(bound); 797 } 798 } 799 800 /* 801 * NOTE: in6_ifdetach() does not support loopback if at this moment. 802 * We don't need this function in bsdi, because interfaces are never removed 803 * from the ifnet list in bsdi. 804 */ 805 void 806 in6_ifdetach(struct ifnet *ifp) 807 { 808 809 /* nuke any of IPv6 addresses we have */ 810 if_purgeaddrs(ifp, AF_INET6, in6_purgeaddr); 811 812 in6_purge_multi(ifp); 813 814 /* remove ip6_mrouter stuff */ 815 ip6_mrouter_detach(ifp); 816 817 /* remove neighbor management table */ 818 nd6_purge(ifp, NULL); 819 820 nd6_assert_purged(ifp); 821 } 822 823 int 824 in6_get_tmpifid(struct ifnet *ifp, u_int8_t *retbuf, 825 const u_int8_t *baseid, int generate) 826 { 827 u_int8_t nullbuf[8]; 828 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 829 830 memset(nullbuf, 0, sizeof(nullbuf)); 831 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) { 832 /* we've never created a random ID. Create a new one. */ 833 generate = 1; 834 } 835 836 if (generate) { 837 memcpy(ndi->randomseed1, baseid, sizeof(ndi->randomseed1)); 838 839 /* generate_tmp_ifid will update seedn and buf */ 840 (void)generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1, 841 ndi->randomid); 842 } 843 memcpy(retbuf, ndi->randomid, 8); 844 if (generate && memcmp(retbuf, nullbuf, sizeof(nullbuf)) == 0) { 845 /* generate_tmp_ifid could not found a good ID. */ 846 return -1; 847 } 848 849 return 0; 850 } 851 852 void 853 in6_tmpaddrtimer_init(void) 854 { 855 856 /* timer for regeneration of temporary addresses randomize ID */ 857 callout_init(&in6_tmpaddrtimer_ch, CALLOUT_MPSAFE); 858 callout_setfunc(&in6_tmpaddrtimer_ch, in6_tmpaddrtimer, NULL); 859 in6_tmpaddrtimer_schedule(); 860 } 861 862 void 863 in6_tmpaddrtimer_schedule(void) 864 { 865 866 callout_schedule(&in6_tmpaddrtimer_ch, 867 (ip6_temp_preferred_lifetime - ip6_desync_factor - 868 ip6_temp_regen_advance) * hz); 869 } 870 871 static void 872 in6_tmpaddrtimer(void *ignored_arg) 873 { 874 struct nd_ifinfo *ndi; 875 u_int8_t nullbuf[8]; 876 struct ifnet *ifp; 877 int s; 878 879 /* XXX NOMPSAFE still need softnet_lock */ 880 mutex_enter(softnet_lock); 881 KERNEL_LOCK(1, NULL); 882 883 in6_tmpaddrtimer_schedule(); 884 885 memset(nullbuf, 0, sizeof(nullbuf)); 886 s = pserialize_read_enter(); 887 IFNET_READER_FOREACH(ifp) { 888 ndi = ND_IFINFO(ifp); 889 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) { 890 /* 891 * We've been generating a random ID on this interface. 892 * Create a new one. 893 */ 894 (void)generate_tmp_ifid(ndi->randomseed0, 895 ndi->randomseed1, ndi->randomid); 896 } 897 } 898 pserialize_read_exit(s); 899 900 KERNEL_UNLOCK_ONE(NULL); 901 mutex_exit(softnet_lock); 902 } 903