in6_ifattach.c revision 1.101
1 /* $NetBSD: in6_ifattach.c,v 1.101 2016/07/07 09:32:03 ozaki-r 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 1.101 2016/07/07 09:32:03 ozaki-r 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; 247 248 IN6_ADDRLIST_READER_FOREACH(ia) { 249 if (!memcmp(&ia->ia_addr.sin6_addr.s6_addr[8], 250 ret, 8)) { 251 badid = 1; 252 break; 253 } 254 } 255 } 256 257 /* 258 * In the event that an unacceptable identifier has been generated, 259 * restart the process, using the right-most 64 bits of the MD5 digest 260 * obtained in place of the history value. 261 */ 262 if (badid) { 263 /* for debugging purposes only */ 264 #if 0 265 { 266 int i; 267 268 printf("unacceptable random ID: "); 269 for (i = 0; i < 16; i++) 270 printf("%02x", digest[i]); 271 printf("\n"); 272 } 273 #endif 274 275 if (++retry < GEN_TEMPID_RETRY_MAX) { 276 memcpy(seed, &digest[8], 8); 277 goto again; 278 } else { 279 /* 280 * We're so unlucky. Give up for now, and return 281 * all 0 IDs to tell the caller not to make a 282 * temporary address. 283 */ 284 nd6log(LOG_NOTICE, "never found a good ID\n"); 285 memset(ret, 0, 8); 286 } 287 } 288 289 /* 290 * draft-ietf-ipngwg-temp-addresses-v2-00.txt 3.2.1. (6) 291 * Take the rightmost 64-bits of the MD5 digest and save them in 292 * stable storage as the history value to be used in the next 293 * iteration of the algorithm. 294 */ 295 memcpy(seed0, &digest[8], 8); 296 297 /* for debugging purposes only */ 298 #if 0 299 { 300 int i; 301 302 printf("to: "); 303 for (i = 0; i < 16; i++) 304 printf("%02x", digest[i]); 305 printf("\n"); 306 } 307 #endif 308 309 return 0; 310 } 311 312 /* 313 * Get interface identifier for the specified interface. 314 * 315 * in6 - upper 64bits are preserved 316 */ 317 int 318 in6_get_hw_ifid(struct ifnet *ifp, struct in6_addr *in6) 319 { 320 struct ifaddr *ifa; 321 const struct sockaddr_dl *sdl = NULL, *tsdl; 322 const char *addr; 323 size_t addrlen; 324 static u_int8_t allzero[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; 325 static u_int8_t allone[8] = 326 { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; 327 328 IFADDR_READER_FOREACH(ifa, ifp) { 329 if (ifa->ifa_addr->sa_family != AF_LINK) 330 continue; 331 tsdl = satocsdl(ifa->ifa_addr); 332 if (tsdl == NULL || tsdl->sdl_alen == 0) 333 continue; 334 if (sdl == NULL || ifa == ifp->if_dl || ifa == ifp->if_hwdl) 335 sdl = tsdl; 336 if (ifa == ifp->if_hwdl) 337 break; 338 } 339 340 if (sdl == NULL) 341 return -1; 342 343 addr = CLLADDR(sdl); 344 addrlen = sdl->sdl_alen; 345 346 switch (ifp->if_type) { 347 case IFT_IEEE1394: 348 case IFT_IEEE80211: 349 /* IEEE1394 uses 16byte length address starting with EUI64 */ 350 if (addrlen > 8) 351 addrlen = 8; 352 break; 353 default: 354 break; 355 } 356 357 /* get EUI64 */ 358 switch (ifp->if_type) { 359 /* IEEE802/EUI64 cases - what others? */ 360 case IFT_ETHER: 361 case IFT_FDDI: 362 case IFT_ATM: 363 case IFT_IEEE1394: 364 case IFT_IEEE80211: 365 /* look at IEEE802/EUI64 only */ 366 if (addrlen != 8 && addrlen != 6) 367 return -1; 368 369 /* 370 * check for invalid MAC address - on bsdi, we see it a lot 371 * since wildboar configures all-zero MAC on pccard before 372 * card insertion. 373 */ 374 if (memcmp(addr, allzero, addrlen) == 0) 375 return -1; 376 if (memcmp(addr, allone, addrlen) == 0) 377 return -1; 378 379 /* make EUI64 address */ 380 if (addrlen == 8) 381 memcpy(&in6->s6_addr[8], addr, 8); 382 else if (addrlen == 6) { 383 in6->s6_addr[8] = addr[0]; 384 in6->s6_addr[9] = addr[1]; 385 in6->s6_addr[10] = addr[2]; 386 in6->s6_addr[11] = 0xff; 387 in6->s6_addr[12] = 0xfe; 388 in6->s6_addr[13] = addr[3]; 389 in6->s6_addr[14] = addr[4]; 390 in6->s6_addr[15] = addr[5]; 391 } 392 break; 393 394 case IFT_ARCNET: 395 if (addrlen != 1) 396 return -1; 397 if (!addr[0]) 398 return -1; 399 400 memset(&in6->s6_addr[8], 0, 8); 401 in6->s6_addr[15] = addr[0]; 402 403 /* 404 * due to insufficient bitwidth, we mark it local. 405 */ 406 in6->s6_addr[8] &= ~EUI64_GBIT; /* g bit to "individual" */ 407 in6->s6_addr[8] |= EUI64_UBIT; /* u bit to "local" */ 408 break; 409 410 case IFT_GIF: 411 #ifdef IFT_STF 412 case IFT_STF: 413 #endif 414 /* 415 * RFC2893 says: "SHOULD use IPv4 address as ifid source". 416 * however, IPv4 address is not very suitable as unique 417 * identifier source (can be renumbered). 418 * we don't do this. 419 */ 420 return -1; 421 422 default: 423 return -1; 424 } 425 426 /* sanity check: g bit must not indicate "group" */ 427 if (EUI64_GROUP(in6)) 428 return -1; 429 430 /* convert EUI64 into IPv6 interface identifier */ 431 EUI64_TO_IFID(in6); 432 433 /* 434 * sanity check: ifid must not be all zero, avoid conflict with 435 * subnet router anycast 436 */ 437 if ((in6->s6_addr[8] & ~(EUI64_GBIT | EUI64_UBIT)) == 0x00 && 438 memcmp(&in6->s6_addr[9], allzero, 7) == 0) { 439 return -1; 440 } 441 442 return 0; 443 } 444 445 /* 446 * Get interface identifier for the specified interface. If it is not 447 * available on ifp0, borrow interface identifier from other information 448 * sources. 449 * 450 * altifp - secondary EUI64 source 451 */ 452 static int 453 get_ifid(struct ifnet *ifp0, struct ifnet *altifp, 454 struct in6_addr *in6) 455 { 456 struct ifnet *ifp; 457 int s; 458 459 /* first, try to get it from the interface itself */ 460 if (in6_get_hw_ifid(ifp0, in6) == 0) { 461 nd6log(LOG_DEBUG, "%s: got interface identifier from itself\n", 462 if_name(ifp0)); 463 goto success; 464 } 465 466 /* try secondary EUI64 source. this basically is for ATM PVC */ 467 if (altifp && in6_get_hw_ifid(altifp, in6) == 0) { 468 nd6log(LOG_DEBUG, "%s: got interface identifier from %s\n", 469 if_name(ifp0), if_name(altifp)); 470 goto success; 471 } 472 473 /* next, try to get it from some other hardware interface */ 474 s = pserialize_read_enter(); 475 IFNET_READER_FOREACH(ifp) { 476 if (ifp == ifp0) 477 continue; 478 if (in6_get_hw_ifid(ifp, in6) != 0) 479 continue; 480 481 /* 482 * to borrow ifid from other interface, ifid needs to be 483 * globally unique 484 */ 485 if (IFID_UNIVERSAL(in6)) { 486 nd6log(LOG_DEBUG, 487 "%s: borrow interface identifier from %s\n", 488 if_name(ifp0), if_name(ifp)); 489 goto success; 490 } 491 } 492 pserialize_read_exit(s); 493 494 #if 0 495 /* get from hostid - only for certain architectures */ 496 if (get_hostid_ifid(ifp, in6) == 0) { 497 nd6log(LOG_DEBUG, 498 "%s: interface identifier generated by hostid\n", 499 if_name(ifp0)); 500 goto success; 501 } 502 #endif 503 504 /* last resort: get from random number source */ 505 if (get_rand_ifid(in6) == 0) { 506 nd6log(LOG_DEBUG, 507 "%s: interface identifier generated by random number\n", 508 if_name(ifp0)); 509 goto success; 510 } 511 512 printf("%s: failed to get interface identifier\n", if_name(ifp0)); 513 return -1; 514 515 success: 516 nd6log(LOG_INFO, "%s: ifid: %02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x\n", 517 if_name(ifp0), in6->s6_addr[8], in6->s6_addr[9], in6->s6_addr[10], 518 in6->s6_addr[11], in6->s6_addr[12], in6->s6_addr[13], 519 in6->s6_addr[14], in6->s6_addr[15]); 520 return 0; 521 } 522 523 /* 524 * altifp - secondary EUI64 source 525 */ 526 527 static int 528 in6_ifattach_linklocal(struct ifnet *ifp, struct ifnet *altifp) 529 { 530 struct in6_ifaddr *ia __diagused; 531 struct in6_aliasreq ifra; 532 struct nd_prefixctl prc0; 533 int i, error; 534 535 /* 536 * configure link-local address. 537 */ 538 memset(&ifra, 0, sizeof(ifra)); 539 540 /* 541 * in6_update_ifa() does not use ifra_name, but we accurately set it 542 * for safety. 543 */ 544 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 545 546 ifra.ifra_addr.sin6_family = AF_INET6; 547 ifra.ifra_addr.sin6_len = sizeof(struct sockaddr_in6); 548 ifra.ifra_addr.sin6_addr.s6_addr32[0] = htonl(0xfe800000); 549 ifra.ifra_addr.sin6_addr.s6_addr32[1] = 0; 550 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 551 ifra.ifra_addr.sin6_addr.s6_addr32[2] = 0; 552 ifra.ifra_addr.sin6_addr.s6_addr32[3] = htonl(1); 553 } else { 554 if (get_ifid(ifp, altifp, &ifra.ifra_addr.sin6_addr) != 0) { 555 nd6log(LOG_ERR, 556 "%s: no ifid available\n", if_name(ifp)); 557 return -1; 558 } 559 } 560 if (in6_setscope(&ifra.ifra_addr.sin6_addr, ifp, NULL)) 561 return -1; 562 563 sockaddr_in6_init(&ifra.ifra_prefixmask, &in6mask64, 0, 0, 0); 564 /* link-local addresses should NEVER expire. */ 565 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 566 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 567 568 /* 569 * Now call in6_update_ifa() to do a bunch of procedures to configure 570 * a link-local address. We can set the 3rd argument to NULL, because 571 * we know there's no other link-local address on the interface 572 * and therefore we are adding one (instead of updating one). 573 */ 574 if ((error = in6_update_ifa(ifp, &ifra, NULL, 575 IN6_IFAUPDATE_DADDELAY)) != 0) { 576 /* 577 * XXX: When the interface does not support IPv6, this call 578 * would fail in the SIOCINITIFADDR ioctl. I believe the 579 * notification is rather confusing in this case, so just 580 * suppress it. (jinmei (at) kame.net 20010130) 581 */ 582 if (error != EAFNOSUPPORT) 583 nd6log(LOG_NOTICE, 584 "failed to configure a link-local address on %s " 585 "(errno=%d)\n", 586 if_name(ifp), error); 587 return -1; 588 } 589 590 ia = in6ifa_ifpforlinklocal(ifp, 0); /* ia must not be NULL */ 591 KASSERTMSG(ia, "ia == NULL in in6_ifattach_linklocal"); 592 593 /* 594 * Make the link-local prefix (fe80::/64%link) as on-link. 595 * Since we'd like to manage prefixes separately from addresses, 596 * we make an ND6 prefix structure for the link-local prefix, 597 * and add it to the prefix list as a never-expire prefix. 598 * XXX: this change might affect some existing code base... 599 */ 600 memset(&prc0, 0, sizeof(prc0)); 601 prc0.ndprc_ifp = ifp; 602 /* this should be 64 at this moment. */ 603 prc0.ndprc_plen = in6_mask2len(&ifra.ifra_prefixmask.sin6_addr, NULL); 604 prc0.ndprc_prefix = ifra.ifra_addr; 605 /* apply the mask for safety. (nd6_prelist_add will apply it again) */ 606 for (i = 0; i < 4; i++) { 607 prc0.ndprc_prefix.sin6_addr.s6_addr32[i] &= 608 in6mask64.s6_addr32[i]; 609 } 610 /* 611 * Initialize parameters. The link-local prefix must always be 612 * on-link, and its lifetimes never expire. 613 */ 614 prc0.ndprc_raf_onlink = 1; 615 prc0.ndprc_raf_auto = 1; /* probably meaningless */ 616 prc0.ndprc_vltime = ND6_INFINITE_LIFETIME; 617 prc0.ndprc_pltime = ND6_INFINITE_LIFETIME; 618 /* 619 * Since there is no other link-local addresses, nd6_prefix_lookup() 620 * probably returns NULL. However, we cannot always expect the result. 621 * For example, if we first remove the (only) existing link-local 622 * address, and then reconfigure another one, the prefix is still 623 * valid with referring to the old link-local address. 624 */ 625 if (nd6_prefix_lookup(&prc0) == NULL) { 626 if ((error = nd6_prelist_add(&prc0, NULL, NULL)) != 0) 627 return error; 628 } 629 630 return 0; 631 } 632 633 /* 634 * ifp - mut be IFT_LOOP 635 */ 636 637 static int 638 in6_ifattach_loopback(struct ifnet *ifp) 639 { 640 struct in6_aliasreq ifra; 641 int error; 642 643 memset(&ifra, 0, sizeof(ifra)); 644 645 /* 646 * in6_update_ifa() does not use ifra_name, but we accurately set it 647 * for safety. 648 */ 649 strncpy(ifra.ifra_name, if_name(ifp), sizeof(ifra.ifra_name)); 650 651 sockaddr_in6_init(&ifra.ifra_prefixmask, &in6mask128, 0, 0, 0); 652 653 /* 654 * Always initialize ia_dstaddr (= broadcast address) to loopback 655 * address. Follows IPv4 practice - see in_ifinit(). 656 */ 657 sockaddr_in6_init(&ifra.ifra_dstaddr, &in6addr_loopback, 0, 0, 0); 658 659 sockaddr_in6_init(&ifra.ifra_addr, &in6addr_loopback, 0, 0, 0); 660 661 /* the loopback address should NEVER expire. */ 662 ifra.ifra_lifetime.ia6t_vltime = ND6_INFINITE_LIFETIME; 663 ifra.ifra_lifetime.ia6t_pltime = ND6_INFINITE_LIFETIME; 664 665 /* we don't need to perform DAD on loopback interfaces. */ 666 ifra.ifra_flags |= IN6_IFF_NODAD; 667 668 /* 669 * We are sure that this is a newly assigned address, so we can set 670 * NULL to the 3rd arg. 671 */ 672 if ((error = in6_update_ifa(ifp, &ifra, NULL, 0)) != 0) { 673 nd6log(LOG_ERR, "failed to configure " 674 "the loopback address on %s (errno=%d)\n", 675 if_name(ifp), error); 676 return -1; 677 } 678 679 return 0; 680 } 681 682 /* 683 * compute NI group address, based on the current hostname setting. 684 * see draft-ietf-ipngwg-icmp-name-lookup-* (04 and later). 685 * 686 * when ifp == NULL, the caller is responsible for filling scopeid. 687 */ 688 int 689 in6_nigroup(struct ifnet *ifp, const char *name, int namelen, 690 struct sockaddr_in6 *sa6) 691 { 692 const char *p; 693 u_int8_t *q; 694 MD5_CTX ctxt; 695 u_int8_t digest[16]; 696 u_int8_t l; 697 u_int8_t n[64]; /* a single label must not exceed 63 chars */ 698 699 if (!namelen || !name) 700 return -1; 701 702 p = name; 703 while (p && *p && *p != '.' && p - name < namelen) 704 p++; 705 if (p - name > sizeof(n) - 1) 706 return -1; /* label too long */ 707 l = p - name; 708 strncpy((char *)n, name, l); 709 n[(int)l] = '\0'; 710 for (q = n; *q; q++) { 711 if ('A' <= *q && *q <= 'Z') 712 *q = *q - 'A' + 'a'; 713 } 714 715 /* generate 8 bytes of pseudo-random value. */ 716 memset(&ctxt, 0, sizeof(ctxt)); 717 MD5Init(&ctxt); 718 MD5Update(&ctxt, &l, sizeof(l)); 719 MD5Update(&ctxt, n, l); 720 MD5Final(digest, &ctxt); 721 722 memset(sa6, 0, sizeof(*sa6)); 723 sa6->sin6_family = AF_INET6; 724 sa6->sin6_len = sizeof(*sa6); 725 sa6->sin6_addr.s6_addr16[0] = htons(0xff02); 726 sa6->sin6_addr.s6_addr8[11] = 2; 727 memcpy(&sa6->sin6_addr.s6_addr32[3], digest, 728 sizeof(sa6->sin6_addr.s6_addr32[3])); 729 if (in6_setscope(&sa6->sin6_addr, ifp, NULL)) 730 return -1; /* XXX: should not fail */ 731 732 return 0; 733 } 734 735 /* 736 * XXX multiple loopback interface needs more care. for instance, 737 * nodelocal address needs to be configured onto only one of them. 738 * XXX multiple link-local address case 739 * 740 * altifp - secondary EUI64 source 741 */ 742 void 743 in6_ifattach(struct ifnet *ifp, struct ifnet *altifp) 744 { 745 struct in6_ifaddr *ia; 746 struct in6_addr in6; 747 748 /* some of the interfaces are inherently not IPv6 capable */ 749 switch (ifp->if_type) { 750 case IFT_BRIDGE: 751 #ifdef IFT_PFLOG 752 case IFT_PFLOG: 753 #endif 754 #ifdef IFT_PFSYNC 755 case IFT_PFSYNC: 756 #endif 757 ND_IFINFO(ifp)->flags &= ~ND6_IFF_AUTO_LINKLOCAL; 758 ND_IFINFO(ifp)->flags |= ND6_IFF_IFDISABLED; 759 return; 760 } 761 762 /* 763 * if link mtu is too small, don't try to configure IPv6. 764 * remember there could be some link-layer that has special 765 * fragmentation logic. 766 */ 767 if (ifp->if_mtu < IPV6_MMTU) { 768 nd6log(LOG_INFO, "%s has too small MTU, IPv6 not enabled\n", 769 if_name(ifp)); 770 return; 771 } 772 773 /* create a multicast kludge storage (if we have not had one) */ 774 in6_createmkludge(ifp); 775 776 /* 777 * quirks based on interface type 778 */ 779 switch (ifp->if_type) { 780 #ifdef IFT_STF 781 case IFT_STF: 782 /* 783 * 6to4 interface is a very special kind of beast. 784 * no multicast, no linklocal. RFC2529 specifies how to make 785 * linklocals for 6to4 interface, but there's no use and 786 * it is rather harmful to have one. 787 */ 788 ND_IFINFO(ifp)->flags &= ~ND6_IFF_AUTO_LINKLOCAL; 789 return; 790 #endif 791 case IFT_CARP: 792 return; 793 default: 794 break; 795 } 796 797 /* 798 * usually, we require multicast capability to the interface 799 */ 800 if ((ifp->if_flags & IFF_MULTICAST) == 0) { 801 nd6log(LOG_INFO, 802 "%s is not multicast capable, IPv6 not enabled\n", 803 if_name(ifp)); 804 return; 805 } 806 807 /* 808 * assign loopback address for loopback interface. 809 * XXX multiple loopback interface case. 810 */ 811 if ((ifp->if_flags & IFF_LOOPBACK) != 0) { 812 in6 = in6addr_loopback; 813 if (in6ifa_ifpwithaddr(ifp, &in6) == NULL) { 814 if (in6_ifattach_loopback(ifp) != 0) 815 return; 816 } 817 } 818 819 /* 820 * assign a link-local address, if there's none. 821 */ 822 if (!(ND_IFINFO(ifp)->flags & ND6_IFF_IFDISABLED) && 823 ND_IFINFO(ifp)->flags & ND6_IFF_AUTO_LINKLOCAL) 824 { 825 ia = in6ifa_ifpforlinklocal(ifp, 0); 826 if (ia == NULL && in6_ifattach_linklocal(ifp, altifp) != 0) { 827 printf("%s: cannot assign link-local address\n", 828 ifp->if_xname); 829 } 830 } 831 } 832 833 /* 834 * NOTE: in6_ifdetach() does not support loopback if at this moment. 835 * We don't need this function in bsdi, because interfaces are never removed 836 * from the ifnet list in bsdi. 837 */ 838 void 839 in6_ifdetach(struct ifnet *ifp) 840 { 841 842 /* remove ip6_mrouter stuff */ 843 ip6_mrouter_detach(ifp); 844 845 /* remove neighbor management table */ 846 nd6_purge(ifp, NULL); 847 848 /* nuke any of IPv6 addresses we have */ 849 if_purgeaddrs(ifp, AF_INET6, in6_purgeaddr); 850 851 /* cleanup multicast address kludge table, if there is any */ 852 in6_purgemkludge(ifp); 853 854 /* 855 * remove neighbor management table. we call it twice just to make 856 * sure we nuke everything. maybe we need just one call. 857 * XXX: since the first call did not release addresses, some prefixes 858 * might remain. We should call nd6_purge() again to release the 859 * prefixes after removing all addresses above. 860 * (Or can we just delay calling nd6_purge until at this point?) 861 */ 862 nd6_purge(ifp, NULL); 863 } 864 865 int 866 in6_get_tmpifid(struct ifnet *ifp, u_int8_t *retbuf, 867 const u_int8_t *baseid, int generate) 868 { 869 u_int8_t nullbuf[8]; 870 struct nd_ifinfo *ndi = ND_IFINFO(ifp); 871 872 memset(nullbuf, 0, sizeof(nullbuf)); 873 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) == 0) { 874 /* we've never created a random ID. Create a new one. */ 875 generate = 1; 876 } 877 878 if (generate) { 879 memcpy(ndi->randomseed1, baseid, sizeof(ndi->randomseed1)); 880 881 /* generate_tmp_ifid will update seedn and buf */ 882 (void)generate_tmp_ifid(ndi->randomseed0, ndi->randomseed1, 883 ndi->randomid); 884 } 885 memcpy(retbuf, ndi->randomid, 8); 886 if (generate && memcmp(retbuf, nullbuf, sizeof(nullbuf)) == 0) { 887 /* generate_tmp_ifid could not found a good ID. */ 888 return -1; 889 } 890 891 return 0; 892 } 893 894 void 895 in6_tmpaddrtimer(void *ignored_arg) 896 { 897 struct nd_ifinfo *ndi; 898 u_int8_t nullbuf[8]; 899 struct ifnet *ifp; 900 int s; 901 902 mutex_enter(softnet_lock); 903 KERNEL_LOCK(1, NULL); 904 905 callout_reset(&in6_tmpaddrtimer_ch, 906 (ip6_temp_preferred_lifetime - ip6_desync_factor - 907 ip6_temp_regen_advance) * hz, in6_tmpaddrtimer, NULL); 908 909 memset(nullbuf, 0, sizeof(nullbuf)); 910 s = pserialize_read_enter(); 911 IFNET_READER_FOREACH(ifp) { 912 ndi = ND_IFINFO(ifp); 913 if (memcmp(ndi->randomid, nullbuf, sizeof(nullbuf)) != 0) { 914 /* 915 * We've been generating a random ID on this interface. 916 * Create a new one. 917 */ 918 (void)generate_tmp_ifid(ndi->randomseed0, 919 ndi->randomseed1, ndi->randomid); 920 } 921 } 922 pserialize_read_exit(s); 923 924 KERNEL_UNLOCK_ONE(NULL); 925 mutex_exit(softnet_lock); 926 } 927
Indexes created Thu Sep 25 16:09:42 GMT 2025