1/* $KAME: name6.c,v 1.25 2000/06/26 16:44:40 itojun Exp $ */ 2 3/* 4 * Copyright (C) 1995, 1996, 1997, 1998, and 1999 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31/* 32 * ++Copyright++ 1985, 1988, 1993 33 * - 34 * Copyright (c) 1985, 1988, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * Redistribution and use in source and binary forms, with or without 38 * modification, are permitted provided that the following conditions 39 * are met: 40 * 1. Redistributions of source code must retain the above copyright 41 * notice, this list of conditions and the following disclaimer. 42 * 2. Redistributions in binary form must reproduce the above copyright 43 * notice, this list of conditions and the following disclaimer in the 44 * documentation and/or other materials provided with the distribution. 45 * 3. All advertising materials mentioning features or use of this software 46 * must display the following acknowledgement: 47 * This product includes software developed by the University of 48 * California, Berkeley and its contributors. 49 * 4. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * - 65 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 66 * 67 * Permission to use, copy, modify, and distribute this software for any 68 * purpose with or without fee is hereby granted, provided that the above 69 * copyright notice and this permission notice appear in all copies, and that 70 * the name of Digital Equipment Corporation not be used in advertising or 71 * publicity pertaining to distribution of the document or software without 72 * specific, written prior permission. 73 * 74 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 75 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 76 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 77 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 78 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 79 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 80 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 81 * SOFTWARE. 82 * - 83 * --Copyright-- 84 */ 85 86/* 87 * Atsushi Onoe <onoe@sm.sony.co.jp> 88 */ 89 90#include <sys/cdefs.h> 91__FBSDID("$FreeBSD$"); 92 93#include "namespace.h" 94#include <sys/param.h> 95#include <sys/socket.h> 96#include <sys/time.h> 97#include <sys/queue.h> 98#include <netinet/in.h> 99#ifdef INET6 100#include <net/if.h> 101#include <net/if_var.h> 102#include <sys/sysctl.h> 103#include <sys/ioctl.h> 104#include <netinet6/in6_var.h> /* XXX */ 105#endif 106 107#include <arpa/inet.h> 108#include <arpa/nameser.h> 109 110#include <errno.h> 111#include <netdb.h> 112#include <resolv.h> 113#include <stdio.h> 114#include <stdlib.h> 115#include <string.h> 116#include <stdarg.h> 117#include <nsswitch.h> 118#include <unistd.h> 119#include "un-namespace.h" 120#include "netdb_private.h" 121#include "res_private.h" 122 123#ifndef MAXALIASES 124#define MAXALIASES 10 125#endif 126#ifndef MAXADDRS 127#define MAXADDRS 20 128#endif 129#ifndef MAXDNAME 130#define MAXDNAME 1025 131#endif 132 133#ifdef INET6 134#define ADDRLEN(af) ((af) == AF_INET6 ? sizeof(struct in6_addr) : \ 135 sizeof(struct in_addr)) 136#else 137#define ADDRLEN(af) sizeof(struct in_addr) 138#endif 139 140#define MAPADDR(ab, ina) \ 141do { \ 142 memcpy(&(ab)->map_inaddr, ina, sizeof(struct in_addr)); \ 143 memset((ab)->map_zero, 0, sizeof((ab)->map_zero)); \ 144 memset((ab)->map_one, 0xff, sizeof((ab)->map_one)); \ 145} while (0) 146#define MAPADDRENABLED(flags) \ 147 (((flags) & AI_V4MAPPED) || \ 148 (((flags) & AI_V4MAPPED_CFG))) 149 150union inx_addr { 151 struct in_addr in_addr; 152#ifdef INET6 153 struct in6_addr in6_addr; 154#endif 155 struct { 156 u_char mau_zero[10]; 157 u_char mau_one[2]; 158 struct in_addr mau_inaddr; 159 } map_addr_un; 160#define map_zero map_addr_un.mau_zero 161#define map_one map_addr_un.mau_one 162#define map_inaddr map_addr_un.mau_inaddr 163}; 164 165struct policyqueue { 166 TAILQ_ENTRY(policyqueue) pc_entry; 167#ifdef INET6 168 struct in6_addrpolicy pc_policy; 169#endif 170}; 171TAILQ_HEAD(policyhead, policyqueue); 172 173#define AIO_SRCFLAG_DEPRECATED 0x1 174 175struct hp_order { 176 union { 177 struct sockaddr_storage aiou_ss; 178 struct sockaddr aiou_sa; 179 } aio_src_un; 180#define aio_srcsa aio_src_un.aiou_sa 181 u_int32_t aio_srcflag; 182 int aio_srcscope; 183 int aio_dstscope; 184 struct policyqueue *aio_srcpolicy; 185 struct policyqueue *aio_dstpolicy; 186 union { 187 struct sockaddr_storage aiou_ss; 188 struct sockaddr aiou_sa; 189 } aio_un; 190#define aio_sa aio_un.aiou_sa 191 int aio_matchlen; 192 char *aio_h_addr; 193}; 194 195static struct hostent *_hpcopy(struct hostent *, int *); 196static struct hostent *_hpaddr(int, const char *, void *, int *); 197#ifdef INET6 198static struct hostent *_hpmerge(struct hostent *, struct hostent *, int *); 199static struct hostent *_hpmapv6(struct hostent *, int *); 200#endif 201static struct hostent *_hpsort(struct hostent *, res_state); 202 203#ifdef INET6 204static struct hostent *_hpreorder(struct hostent *); 205static int get_addrselectpolicy(struct policyhead *); 206static void free_addrselectpolicy(struct policyhead *); 207static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 208 struct policyhead *); 209static void set_source(struct hp_order *, struct policyhead *); 210static int matchlen(struct sockaddr *, struct sockaddr *); 211static int comp_dst(const void *, const void *); 212static int gai_addr2scopetype(struct sockaddr *); 213#endif 214 215/* 216 * Functions defined in RFC2553 217 * getipnodebyname, getipnodebyaddr, freehostent 218 */ 219 220struct hostent * 221getipnodebyname(const char *name, int af, int flags, int *errp) 222{ 223 struct hostent *hp; 224 union inx_addr addrbuf; 225 res_state statp; 226 u_long options; 227 228 switch (af) { 229 case AF_INET: 230#ifdef INET6 231 case AF_INET6: 232#endif 233 break; 234 default: 235 *errp = NO_RECOVERY; 236 return NULL; 237 } 238 239 if (flags & AI_ADDRCONFIG) { 240 int s; 241 242 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0) 243 return NULL; 244 /* 245 * TODO: 246 * Note that implementation dependent test for address 247 * configuration should be done everytime called 248 * (or apropriate interval), 249 * because addresses will be dynamically assigned or deleted. 250 */ 251 _close(s); 252 } 253 254#ifdef INET6 255 /* special case for literal address */ 256 if (inet_pton(AF_INET6, name, &addrbuf) == 1) { 257 if (af != AF_INET6) { 258 *errp = HOST_NOT_FOUND; 259 return NULL; 260 } 261 return _hpaddr(af, name, &addrbuf, errp); 262 } 263#endif 264 if (inet_aton(name, (struct in_addr *)&addrbuf) == 1) { 265 if (af != AF_INET) { 266 if (MAPADDRENABLED(flags)) { 267 MAPADDR(&addrbuf, &addrbuf.in_addr); 268 } else { 269 *errp = HOST_NOT_FOUND; 270 return NULL; 271 } 272 } 273 return _hpaddr(af, name, &addrbuf, errp); 274 } 275 276 277 statp = __res_state(); 278 if ((statp->options & RES_INIT) == 0) { 279 if (res_ninit(statp) < 0) { 280 *errp = NETDB_INTERNAL; 281 return NULL; 282 } 283 } 284 285 options = statp->options; 286 statp->options &= ~RES_USE_INET6; 287 288 hp = gethostbyname2(name, af); 289 hp = _hpcopy(hp, errp); 290#ifdef INET6 291 if (af == AF_INET6) 292 hp = _hpreorder(hp); 293 294 if (af == AF_INET6 && ((flags & AI_ALL) || hp == NULL) && 295 MAPADDRENABLED(flags)) { 296 struct hostent *hp2 = gethostbyname2(name, AF_INET); 297 if (hp == NULL) 298 if (hp2 == NULL) 299 *errp = statp->res_h_errno; 300 else 301 hp = _hpmapv6(hp2, errp); 302 else { 303 if (hp2 && strcmp(hp->h_name, hp2->h_name) == 0) { 304 struct hostent *hpb = hp; 305 hp = _hpmerge(hpb, hp2, errp); 306 freehostent(hpb); 307 } 308 } 309 } 310#endif 311 312 if (hp == NULL) 313 *errp = statp->res_h_errno; 314 315 statp->options = options; 316 return _hpsort(hp, statp); 317} 318 319struct hostent * 320getipnodebyaddr(const void *src, size_t len, int af, int *errp) 321{ 322 struct hostent *hp; 323 res_state statp; 324 u_long options; 325 326#ifdef INET6 327 struct in6_addr addrbuf; 328#else 329 struct in_addr addrbuf; 330#endif 331 332 switch (af) { 333 case AF_INET: 334 if (len != sizeof(struct in_addr)) { 335 *errp = NO_RECOVERY; 336 return NULL; 337 } 338 if ((long)src & ~(sizeof(struct in_addr) - 1)) { 339 memcpy(&addrbuf, src, len); 340 src = &addrbuf; 341 } 342 if (((struct in_addr *)src)->s_addr == 0) 343 return NULL; 344 break; 345#ifdef INET6 346 case AF_INET6: 347 if (len != sizeof(struct in6_addr)) { 348 *errp = NO_RECOVERY; 349 return NULL; 350 } 351 if ((long)src & ~(sizeof(struct in6_addr) / 2 - 1)) { /*XXX*/ 352 memcpy(&addrbuf, src, len); 353 src = &addrbuf; 354 } 355 if (IN6_IS_ADDR_UNSPECIFIED((struct in6_addr *)src)) 356 return NULL; 357 if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)src) 358 || IN6_IS_ADDR_V4COMPAT((struct in6_addr *)src)) { 359 src = (char *)src + 360 (sizeof(struct in6_addr) - sizeof(struct in_addr)); 361 af = AF_INET; 362 len = sizeof(struct in_addr); 363 } 364 break; 365#endif 366 default: 367 *errp = NO_RECOVERY; 368 return NULL; 369 } 370 371 statp = __res_state(); 372 if ((statp->options & RES_INIT) == 0) { 373 if (res_ninit(statp) < 0) { 374 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 375 return NULL; 376 } 377 } 378 379 options = statp->options; 380 statp->options &= ~RES_USE_INET6; 381 382 hp = gethostbyaddr(src, len, af); 383 if (hp == NULL) 384 *errp = statp->res_h_errno; 385 386 statp->options = options; 387 return (_hpcopy(hp, errp)); 388} 389 390void 391freehostent(struct hostent *ptr) 392{ 393 free(ptr); 394} 395 396/* 397 * Private utility functions 398 */ 399 400/* 401 * _hpcopy: allocate and copy hostent structure 402 */ 403static struct hostent * 404_hpcopy(struct hostent *hp, int *errp) 405{ 406 struct hostent *nhp; 407 char *cp, **pp; 408 int size, addrsize; 409 int nalias = 0, naddr = 0; 410 int al_off; 411 int i; 412 413 if (hp == NULL) 414 return hp; 415 416 /* count size to be allocated */ 417 size = sizeof(struct hostent); 418 if (hp->h_name != NULL) 419 size += strlen(hp->h_name) + 1; 420 if ((pp = hp->h_aliases) != NULL) { 421 for (i = 0; *pp != NULL; i++, pp++) { 422 if (**pp != '\0') { 423 size += strlen(*pp) + 1; 424 nalias++; 425 } 426 } 427 } 428 /* adjust alignment */ 429 size = ALIGN(size); 430 al_off = size; 431 size += sizeof(char *) * (nalias + 1); 432 addrsize = ALIGN(hp->h_length); 433 if ((pp = hp->h_addr_list) != NULL) { 434 while (*pp++ != NULL) 435 naddr++; 436 } 437 size += addrsize * naddr; 438 size += sizeof(char *) * (naddr + 1); 439 440 /* copy */ 441 if ((nhp = (struct hostent *)malloc(size)) == NULL) { 442 *errp = TRY_AGAIN; 443 return NULL; 444 } 445 cp = (char *)&nhp[1]; 446 if (hp->h_name != NULL) { 447 nhp->h_name = cp; 448 strcpy(cp, hp->h_name); 449 cp += strlen(cp) + 1; 450 } else 451 nhp->h_name = NULL; 452 nhp->h_aliases = (char **)((char *)nhp + al_off); 453 if ((pp = hp->h_aliases) != NULL) { 454 for (i = 0; *pp != NULL; pp++) { 455 if (**pp != '\0') { 456 nhp->h_aliases[i++] = cp; 457 strcpy(cp, *pp); 458 cp += strlen(cp) + 1; 459 } 460 } 461 } 462 nhp->h_aliases[nalias] = NULL; 463 cp = (char *)&nhp->h_aliases[nalias + 1]; 464 nhp->h_addrtype = hp->h_addrtype; 465 nhp->h_length = hp->h_length; 466 nhp->h_addr_list = (char **)cp; 467 if ((pp = hp->h_addr_list) != NULL) { 468 cp = (char *)&nhp->h_addr_list[naddr + 1]; 469 for (i = 0; *pp != NULL; pp++) { 470 nhp->h_addr_list[i++] = cp; 471 memcpy(cp, *pp, hp->h_length); 472 cp += addrsize; 473 } 474 } 475 nhp->h_addr_list[naddr] = NULL; 476 return nhp; 477} 478 479/* 480 * _hpaddr: construct hostent structure with one address 481 */ 482static struct hostent * 483_hpaddr(int af, const char *name, void *addr, int *errp) 484{ 485 struct hostent *hp, hpbuf; 486 char *addrs[2]; 487 488 hp = &hpbuf; 489 hp->h_name = (char *)name; 490 hp->h_aliases = NULL; 491 hp->h_addrtype = af; 492 hp->h_length = ADDRLEN(af); 493 hp->h_addr_list = addrs; 494 addrs[0] = (char *)addr; 495 addrs[1] = NULL; 496 return (_hpcopy(hp, errp)); 497} 498 499#ifdef INET6 500/* 501 * _hpmerge: merge 2 hostent structure, arguments will be freed 502 */ 503static struct hostent * 504_hpmerge(struct hostent *hp1, struct hostent *hp2, int *errp) 505{ 506 int i, j; 507 int naddr, nalias; 508 char **pp; 509 struct hostent *hp, hpbuf; 510 char *aliases[MAXALIASES + 1], *addrs[MAXADDRS + 1]; 511 union inx_addr addrbuf[MAXADDRS]; 512 513 if (hp1 == NULL) 514 return _hpcopy(hp2, errp); 515 if (hp2 == NULL) 516 return _hpcopy(hp1, errp); 517 518#define HP(i) (i == 1 ? hp1 : hp2) 519 hp = &hpbuf; 520 hp->h_name = (hp1->h_name != NULL ? hp1->h_name : hp2->h_name); 521 hp->h_aliases = aliases; 522 nalias = 0; 523 for (i = 1; i <= 2; i++) { 524 if ((pp = HP(i)->h_aliases) == NULL) 525 continue; 526 for (; nalias < MAXALIASES && *pp != NULL; pp++) { 527 /* check duplicates */ 528 for (j = 0; j < nalias; j++) 529 if (strcasecmp(*pp, aliases[j]) == 0) 530 break; 531 if (j == nalias) 532 aliases[nalias++] = *pp; 533 } 534 } 535 aliases[nalias] = NULL; 536 if (hp1->h_length != hp2->h_length) { 537 hp->h_addrtype = AF_INET6; 538 hp->h_length = sizeof(struct in6_addr); 539 } else { 540 hp->h_addrtype = hp1->h_addrtype; 541 hp->h_length = hp1->h_length; 542 } 543 544 hp->h_addr_list = addrs; 545 naddr = 0; 546 for (i = 1; i <= 2; i++) { 547 if ((pp = HP(i)->h_addr_list) == NULL) 548 continue; 549 if (HP(i)->h_length == hp->h_length) { 550 while (naddr < MAXADDRS && *pp != NULL) 551 addrs[naddr++] = *pp++; 552 } else { 553 /* copy IPv4 addr as mapped IPv6 addr */ 554 while (naddr < MAXADDRS && *pp != NULL) { 555 MAPADDR(&addrbuf[naddr], *pp++); 556 addrs[naddr] = (char *)&addrbuf[naddr]; 557 naddr++; 558 } 559 } 560 } 561 addrs[naddr] = NULL; 562 return (_hpcopy(hp, errp)); 563} 564#endif 565 566/* 567 * _hpmapv6: convert IPv4 hostent into IPv4-mapped IPv6 addresses 568 */ 569#ifdef INET6 570static struct hostent * 571_hpmapv6(struct hostent *hp, int *errp) 572{ 573 struct hostent hp6; 574 575 if (hp == NULL) 576 return NULL; 577 if (hp->h_addrtype == AF_INET6) 578 return _hpcopy(hp, errp); 579 580 memset(&hp6, 0, sizeof(struct hostent)); 581 hp6.h_addrtype = AF_INET6; 582 hp6.h_length = sizeof(struct in6_addr); 583 return _hpmerge(&hp6, hp, errp); 584} 585#endif 586 587/* 588 * _hpsort: sort address by sortlist 589 */ 590static struct hostent * 591_hpsort(struct hostent *hp, res_state statp) 592{ 593 int i, j, n; 594 u_char *ap, *sp, *mp, **pp; 595 char t; 596 char order[MAXADDRS]; 597 int nsort = statp->nsort; 598 599 if (hp == NULL || hp->h_addr_list[1] == NULL || nsort == 0) 600 return hp; 601 for (i = 0; (ap = (u_char *)hp->h_addr_list[i]); i++) { 602 for (j = 0; j < nsort; j++) { 603#ifdef INET6 604 if (statp->_u._ext.ext->sort_list[j].af != 605 hp->h_addrtype) 606 continue; 607 sp = (u_char *)&statp->_u._ext.ext->sort_list[j].addr; 608 mp = (u_char *)&statp->_u._ext.ext->sort_list[j].mask; 609#else 610 sp = (u_char *)&statp->sort_list[j].addr; 611 mp = (u_char *)&statp->sort_list[j].mask; 612#endif 613 for (n = 0; n < hp->h_length; n++) { 614 if ((ap[n] & mp[n]) != sp[n]) 615 break; 616 } 617 if (n == hp->h_length) 618 break; 619 } 620 order[i] = j; 621 } 622 n = i; 623 pp = (u_char **)hp->h_addr_list; 624 for (i = 0; i < n - 1; i++) { 625 for (j = i + 1; j < n; j++) { 626 if (order[i] > order[j]) { 627 ap = pp[i]; 628 pp[i] = pp[j]; 629 pp[j] = ap; 630 t = order[i]; 631 order[i] = order[j]; 632 order[j] = t; 633 } 634 } 635 } 636 return hp; 637} 638 639#ifdef INET6 640/* 641 * _hpreorder: sort address by default address selection 642 */ 643static struct hostent * 644_hpreorder(struct hostent *hp) 645{ 646 struct hp_order *aio; 647 int i, n; 648 char *ap; 649 struct sockaddr *sa; 650 struct policyhead policyhead; 651 652 if (hp == NULL) 653 return hp; 654 655 switch (hp->h_addrtype) { 656 case AF_INET: 657#ifdef INET6 658 case AF_INET6: 659#endif 660 break; 661 default: 662 free_addrselectpolicy(&policyhead); 663 return hp; 664 } 665 666 /* count the number of addrinfo elements for sorting. */ 667 for (n = 0; hp->h_addr_list[n] != NULL; n++) 668 ; 669 670 /* 671 * If the number is small enough, we can skip the reordering process. 672 */ 673 if (n <= 1) 674 return hp; 675 676 /* allocate a temporary array for sort and initialization of it. */ 677 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 678 return hp; /* give up reordering */ 679 memset(aio, 0, sizeof(*aio) * n); 680 681 /* retrieve address selection policy from the kernel */ 682 TAILQ_INIT(&policyhead); 683 if (!get_addrselectpolicy(&policyhead)) { 684 /* no policy is installed into kernel, we don't sort. */ 685 free(aio); 686 return hp; 687 } 688 689 for (i = 0; i < n; i++) { 690 ap = hp->h_addr_list[i]; 691 aio[i].aio_h_addr = ap; 692 sa = &aio[i].aio_sa; 693 switch (hp->h_addrtype) { 694 case AF_INET: 695 sa->sa_family = AF_INET; 696 sa->sa_len = sizeof(struct sockaddr_in); 697 memcpy(&((struct sockaddr_in *)sa)->sin_addr, ap, 698 sizeof(struct in_addr)); 699 break; 700#ifdef INET6 701 case AF_INET6: 702 if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) { 703 sa->sa_family = AF_INET; 704 sa->sa_len = sizeof(struct sockaddr_in); 705 memcpy(&((struct sockaddr_in *)sa)->sin_addr, 706 &ap[12], sizeof(struct in_addr)); 707 } else { 708 sa->sa_family = AF_INET6; 709 sa->sa_len = sizeof(struct sockaddr_in6); 710 memcpy(&((struct sockaddr_in6 *)sa)->sin6_addr, 711 ap, sizeof(struct in6_addr)); 712 } 713 break; 714#endif 715 } 716 aio[i].aio_dstscope = gai_addr2scopetype(sa); 717 aio[i].aio_dstpolicy = match_addrselectpolicy(sa, &policyhead); 718 set_source(&aio[i], &policyhead); 719 } 720 721 /* perform sorting. */ 722 qsort(aio, n, sizeof(*aio), comp_dst); 723 724 /* reorder the h_addr_list. */ 725 for (i = 0; i < n; i++) 726 hp->h_addr_list[i] = aio[i].aio_h_addr; 727 728 /* cleanup and return */ 729 free(aio); 730 free_addrselectpolicy(&policyhead); 731 return hp; 732} 733 734static int 735get_addrselectpolicy(struct policyhead *head) 736{ 737#ifdef INET6 738 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 739 size_t l; 740 char *buf; 741 struct in6_addrpolicy *pol, *ep; 742 743 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0) 744 return (0); 745 if ((buf = malloc(l)) == NULL) 746 return (0); 747 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) { 748 free(buf); 749 return (0); 750 } 751 752 ep = (struct in6_addrpolicy *)(buf + l); 753 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 754 struct policyqueue *new; 755 756 if ((new = malloc(sizeof(*new))) == NULL) { 757 free_addrselectpolicy(head); /* make the list empty */ 758 break; 759 } 760 new->pc_policy = *pol; 761 TAILQ_INSERT_TAIL(head, new, pc_entry); 762 } 763 764 free(buf); 765 return (1); 766#else 767 return (0); 768#endif 769} 770 771static void 772free_addrselectpolicy(struct policyhead *head) 773{ 774 struct policyqueue *ent, *nent; 775 776 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 777 nent = TAILQ_NEXT(ent, pc_entry); 778 TAILQ_REMOVE(head, ent, pc_entry); 779 free(ent); 780 } 781} 782 783static struct policyqueue * 784match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 785{ 786#ifdef INET6 787 struct policyqueue *ent, *bestent = NULL; 788 struct in6_addrpolicy *pol; 789 int matchlen, bestmatchlen = -1; 790 u_char *mp, *ep, *k, *p, m; 791 struct sockaddr_in6 key; 792 793 switch(addr->sa_family) { 794 case AF_INET6: 795 key = *(struct sockaddr_in6 *)addr; 796 break; 797 case AF_INET: 798 /* convert the address into IPv4-mapped IPv6 address. */ 799 memset(&key, 0, sizeof(key)); 800 key.sin6_family = AF_INET6; 801 key.sin6_len = sizeof(key); 802 key.sin6_addr.s6_addr[10] = 0xff; 803 key.sin6_addr.s6_addr[11] = 0xff; 804 memcpy(&key.sin6_addr.s6_addr[12], 805 &((struct sockaddr_in *)addr)->sin_addr, 4); 806 break; 807 default: 808 return(NULL); 809 } 810 811 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 812 pol = &ent->pc_policy; 813 matchlen = 0; 814 815 mp = (u_char *)&pol->addrmask.sin6_addr; 816 ep = mp + 16; /* XXX: scope field? */ 817 k = (u_char *)&key.sin6_addr; 818 p = (u_char *)&pol->addr.sin6_addr; 819 for (; mp < ep && *mp; mp++, k++, p++) { 820 m = *mp; 821 if ((*k & m) != *p) 822 goto next; /* not match */ 823 if (m == 0xff) /* short cut for a typical case */ 824 matchlen += 8; 825 else { 826 while (m >= 0x80) { 827 matchlen++; 828 m <<= 1; 829 } 830 } 831 } 832 833 /* matched. check if this is better than the current best. */ 834 if (matchlen > bestmatchlen) { 835 bestent = ent; 836 bestmatchlen = matchlen; 837 } 838 839 next: 840 continue; 841 } 842 843 return(bestent); 844#else 845 return(NULL); 846#endif 847 848} 849 850static void 851set_source(struct hp_order *aio, struct policyhead *ph) 852{ 853 struct sockaddr_storage ss = aio->aio_un.aiou_ss; 854 socklen_t srclen; 855 int s; 856 857 /* set unspec ("no source is available"), just in case */ 858 aio->aio_srcsa.sa_family = AF_UNSPEC; 859 aio->aio_srcscope = -1; 860 861 switch(ss.ss_family) { 862 case AF_INET: 863 ((struct sockaddr_in *)&ss)->sin_port = htons(1); 864 break; 865#ifdef INET6 866 case AF_INET6: 867 ((struct sockaddr_in6 *)&ss)->sin6_port = htons(1); 868 break; 869#endif 870 default: /* ignore unsupported AFs explicitly */ 871 return; 872 } 873 874 /* open a socket to get the source address for the given dst */ 875 if ((s = _socket(ss.ss_family, SOCK_DGRAM, IPPROTO_UDP)) < 0) 876 return; /* give up */ 877 if (_connect(s, (struct sockaddr *)&ss, ss.ss_len) < 0) 878 goto cleanup; 879 srclen = ss.ss_len; 880 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 881 aio->aio_srcsa.sa_family = AF_UNSPEC; 882 goto cleanup; 883 } 884 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 885 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 886 aio->aio_matchlen = matchlen(&aio->aio_srcsa, (struct sockaddr *)&ss); 887#ifdef INET6 888 if (ss.ss_family == AF_INET6) { 889 struct in6_ifreq ifr6; 890 u_int32_t flags6; 891 892 memset(&ifr6, 0, sizeof(ifr6)); 893 memcpy(&ifr6.ifr_addr, &ss, ss.ss_len); 894 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 895 flags6 = ifr6.ifr_ifru.ifru_flags6; 896 if ((flags6 & IN6_IFF_DEPRECATED)) 897 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 898 } 899 } 900#endif 901 902 cleanup: 903 _close(s); 904 return; 905} 906 907static int 908matchlen(struct sockaddr *src, struct sockaddr *dst) 909{ 910 int match = 0; 911 u_char *s, *d; 912 u_char *lim, r; 913 int addrlen; 914 915 switch (src->sa_family) { 916#ifdef INET6 917 case AF_INET6: 918 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 919 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 920 addrlen = sizeof(struct in6_addr); 921 lim = s + addrlen; 922 break; 923#endif 924 case AF_INET: 925 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 926 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 927 addrlen = sizeof(struct in_addr); 928 lim = s + addrlen; 929 break; 930 default: 931 return(0); 932 } 933 934 while (s < lim) 935 if ((r = (*d++ ^ *s++)) != 0) { 936 while (r < addrlen * 8) { 937 match++; 938 r <<= 1; 939 } 940 break; 941 } else 942 match += 8; 943 return(match); 944} 945 946static int 947comp_dst(const void *arg1, const void *arg2) 948{ 949 const struct hp_order *dst1 = arg1, *dst2 = arg2; 950 951 /* 952 * Rule 1: Avoid unusable destinations. 953 * XXX: we currently do not consider if an appropriate route exists. 954 */ 955 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 956 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 957 return(-1); 958 } 959 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 960 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 961 return(1); 962 } 963 964 /* Rule 2: Prefer matching scope. */ 965 if (dst1->aio_dstscope == dst1->aio_srcscope && 966 dst2->aio_dstscope != dst2->aio_srcscope) { 967 return(-1); 968 } 969 if (dst1->aio_dstscope != dst1->aio_srcscope && 970 dst2->aio_dstscope == dst2->aio_srcscope) { 971 return(1); 972 } 973 974 /* Rule 3: Avoid deprecated addresses. */ 975 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 976 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 977 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 978 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 979 return(-1); 980 } 981 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 982 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 983 return(1); 984 } 985 } 986 987 /* Rule 4: Prefer home addresses. */ 988 /* XXX: not implemented yet */ 989 990 /* Rule 5: Prefer matching label. */ 991#ifdef INET6 992 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 993 dst1->aio_srcpolicy->pc_policy.label == 994 dst1->aio_dstpolicy->pc_policy.label && 995 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 996 dst2->aio_srcpolicy->pc_policy.label != 997 dst2->aio_dstpolicy->pc_policy.label)) { 998 return(-1); 999 } 1000 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 1001 dst2->aio_srcpolicy->pc_policy.label == 1002 dst2->aio_dstpolicy->pc_policy.label && 1003 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 1004 dst1->aio_srcpolicy->pc_policy.label != 1005 dst1->aio_dstpolicy->pc_policy.label)) { 1006 return(1); 1007 } 1008#endif 1009 1010 /* Rule 6: Prefer higher precedence. */ 1011#ifdef INET6 1012 if (dst1->aio_dstpolicy && 1013 (dst2->aio_dstpolicy == NULL || 1014 dst1->aio_dstpolicy->pc_policy.preced > 1015 dst2->aio_dstpolicy->pc_policy.preced)) { 1016 return(-1); 1017 } 1018 if (dst2->aio_dstpolicy && 1019 (dst1->aio_dstpolicy == NULL || 1020 dst2->aio_dstpolicy->pc_policy.preced > 1021 dst1->aio_dstpolicy->pc_policy.preced)) { 1022 return(1); 1023 } 1024#endif 1025 1026 /* Rule 7: Prefer native transport. */ 1027 /* XXX: not implemented yet */ 1028 1029 /* Rule 8: Prefer smaller scope. */ 1030 if (dst1->aio_dstscope >= 0 && 1031 dst1->aio_dstscope < dst2->aio_dstscope) { 1032 return(-1); 1033 } 1034 if (dst2->aio_dstscope >= 0 && 1035 dst2->aio_dstscope < dst1->aio_dstscope) { 1036 return(1); 1037 } 1038 1039 /* 1040 * Rule 9: Use longest matching prefix. 1041 * We compare the match length in a same AF only. 1042 */ 1043 if (dst1->aio_sa.sa_family == dst2->aio_sa.sa_family) { 1044 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1045 return(-1); 1046 } 1047 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1048 return(1); 1049 } 1050 } 1051 1052 /* Rule 10: Otherwise, leave the order unchanged. */ 1053 return(-1); 1054} 1055 1056/* 1057 * Copy from scope.c. 1058 * XXX: we should standardize the functions and link them as standard 1059 * library. 1060 */ 1061static int 1062gai_addr2scopetype(struct sockaddr *sa) 1063{ 1064#ifdef INET6 1065 struct sockaddr_in6 *sa6; 1066#endif 1067 struct sockaddr_in *sa4; 1068 1069 switch(sa->sa_family) { 1070#ifdef INET6 1071 case AF_INET6: 1072 sa6 = (struct sockaddr_in6 *)sa; 1073 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1074 /* just use the scope field of the multicast address */ 1075 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1076 } 1077 /* 1078 * Unicast addresses: map scope type to corresponding scope 1079 * value defined for multcast addresses. 1080 * XXX: hardcoded scope type values are bad... 1081 */ 1082 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1083 return(1); /* node local scope */ 1084 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1085 return(2); /* link-local scope */ 1086 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1087 return(5); /* site-local scope */ 1088 return(14); /* global scope */ 1089 break; 1090#endif 1091 case AF_INET: 1092 /* 1093 * IPv4 pseudo scoping according to RFC 3484. 1094 */ 1095 sa4 = (struct sockaddr_in *)sa; 1096 /* IPv4 autoconfiguration addresses have link-local scope. */ 1097 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1098 ((u_char *)&sa4->sin_addr)[1] == 254) 1099 return(2); 1100 /* Private addresses have site-local scope. */ 1101 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1102 (((u_char *)&sa4->sin_addr)[0] == 172 && 1103 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1104 (((u_char *)&sa4->sin_addr)[0] == 192 && 1105 ((u_char *)&sa4->sin_addr)[1] == 168)) 1106 return(14); /* XXX: It should be 5 unless NAT */ 1107 /* Loopback addresses have link-local scope. */ 1108 if (((u_char *)&sa4->sin_addr)[0] == 127) 1109 return(2); 1110 return(14); 1111 break; 1112 default: 1113 errno = EAFNOSUPPORT; /* is this a good error? */ 1114 return(-1); 1115 } 1116} 1117#endif 1118