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. Neither the name of the University nor the names of its contributors 46 * may be used to endorse or promote products derived from this software 47 * without specific prior written permission. 48 * 49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 59 * SUCH DAMAGE. 60 * - 61 * Portions Copyright (c) 1993 by Digital Equipment Corporation. 62 * 63 * Permission to use, copy, modify, and distribute this software for any 64 * purpose with or without fee is hereby granted, provided that the above 65 * copyright notice and this permission notice appear in all copies, and that 66 * the name of Digital Equipment Corporation not be used in advertising or 67 * publicity pertaining to distribution of the document or software without 68 * specific, written prior permission. 69 * 70 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL 71 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES 72 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT 73 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL 74 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR 75 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 76 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 77 * SOFTWARE. 78 * - 79 * --Copyright-- 80 */ 81 82/* 83 * Atsushi Onoe <onoe@sm.sony.co.jp> 84 */ 85 86#include <sys/cdefs.h> 87__FBSDID("$FreeBSD: releng/11.0/lib/libc/net/name6.c 299922 2016-05-16 08:13:30Z truckman $"); 88 89#include "namespace.h" 90#include <sys/param.h> 91#include <sys/socket.h> 92#include <sys/time.h> 93#include <sys/queue.h> 94#include <netinet/in.h> 95#ifdef INET6 96#include <net/if.h> 97#include <sys/sysctl.h> 98#include <sys/ioctl.h> 99#include <netinet6/in6_var.h> /* XXX */ 100#endif 101 102#include <arpa/inet.h> 103#include <arpa/nameser.h> 104 105#include <errno.h> 106#include <netdb.h> 107#include <resolv.h> 108#include <stdio.h> 109#include <stdlib.h> 110#include <string.h> 111#include <stdarg.h> 112#include <nsswitch.h> 113#include <unistd.h> 114#include "un-namespace.h" 115#include "netdb_private.h" 116#include "res_private.h" 117 118#ifndef MAXALIASES 119#define MAXALIASES 10 120#endif 121#ifndef MAXADDRS 122#define MAXADDRS 20 123#endif 124#ifndef MAXDNAME 125#define MAXDNAME 1025 126#endif 127 128#ifdef INET6 129#define ADDRLEN(af) ((af) == AF_INET6 ? sizeof(struct in6_addr) : \ 130 sizeof(struct in_addr)) 131#else 132#define ADDRLEN(af) sizeof(struct in_addr) 133#endif 134 135#define MAPADDR(ab, ina) \ 136do { \ 137 memcpy(&(ab)->map_inaddr, ina, sizeof(struct in_addr)); \ 138 memset((ab)->map_zero, 0, sizeof((ab)->map_zero)); \ 139 memset((ab)->map_one, 0xff, sizeof((ab)->map_one)); \ 140} while (0) 141#define MAPADDRENABLED(flags) \ 142 (((flags) & AI_V4MAPPED) || \ 143 (((flags) & AI_V4MAPPED_CFG))) 144 145union inx_addr { 146 struct in_addr in_addr; 147#ifdef INET6 148 struct in6_addr in6_addr; 149#endif 150 struct { 151 u_char mau_zero[10]; 152 u_char mau_one[2]; 153 struct in_addr mau_inaddr; 154 } map_addr_un; 155#define map_zero map_addr_un.mau_zero 156#define map_one map_addr_un.mau_one 157#define map_inaddr map_addr_un.mau_inaddr 158}; 159 160struct policyqueue { 161 TAILQ_ENTRY(policyqueue) pc_entry; 162#ifdef INET6 163 struct in6_addrpolicy pc_policy; 164#endif 165}; 166TAILQ_HEAD(policyhead, policyqueue); 167 168#define AIO_SRCFLAG_DEPRECATED 0x1 169 170struct hp_order { 171 union { 172 struct sockaddr_storage aiou_ss; 173 struct sockaddr aiou_sa; 174 } aio_src_un; 175#define aio_srcsa aio_src_un.aiou_sa 176 u_int32_t aio_srcflag; 177 int aio_srcscope; 178 int aio_dstscope; 179 struct policyqueue *aio_srcpolicy; 180 struct policyqueue *aio_dstpolicy; 181 union { 182 struct sockaddr_storage aiou_ss; 183 struct sockaddr aiou_sa; 184 } aio_un; 185#define aio_sa aio_un.aiou_sa 186 int aio_matchlen; 187 char *aio_h_addr; 188}; 189 190static struct hostent *_hpcopy(struct hostent *, int *); 191static struct hostent *_hpaddr(int, const char *, void *, int *); 192#ifdef INET6 193static struct hostent *_hpmerge(struct hostent *, struct hostent *, int *); 194static struct hostent *_hpmapv6(struct hostent *, int *); 195#endif 196static struct hostent *_hpsort(struct hostent *, res_state); 197 198#ifdef INET6 199static struct hostent *_hpreorder(struct hostent *); 200static int get_addrselectpolicy(struct policyhead *); 201static void free_addrselectpolicy(struct policyhead *); 202static struct policyqueue *match_addrselectpolicy(struct sockaddr *, 203 struct policyhead *); 204static void set_source(struct hp_order *, struct policyhead *); 205static int matchlen(struct sockaddr *, struct sockaddr *); 206static int comp_dst(const void *, const void *); 207static int gai_addr2scopetype(struct sockaddr *); 208#endif 209 210/* 211 * Functions defined in RFC2553 212 * getipnodebyname, getipnodebyaddr, freehostent 213 */ 214 215struct hostent * 216getipnodebyname(const char *name, int af, int flags, int *errp) 217{ 218 struct hostent *hp; 219 union inx_addr addrbuf; 220 res_state statp; 221 u_long options; 222 223 switch (af) { 224 case AF_INET: 225#ifdef INET6 226 case AF_INET6: 227#endif 228 break; 229 default: 230 *errp = NO_RECOVERY; 231 return NULL; 232 } 233 234 if (flags & AI_ADDRCONFIG) { 235 int s; 236 237 if ((s = _socket(af, SOCK_DGRAM | SOCK_CLOEXEC, 0)) < 0) 238 return NULL; 239 /* 240 * TODO: 241 * Note that implementation dependent test for address 242 * configuration should be done every time called 243 * (or appropriate interval), 244 * because addresses will be dynamically assigned or deleted. 245 */ 246 _close(s); 247 } 248 249#ifdef INET6 250 /* special case for literal address */ 251 if (inet_pton(AF_INET6, name, &addrbuf) == 1) { 252 if (af != AF_INET6) { 253 *errp = HOST_NOT_FOUND; 254 return NULL; 255 } 256 return _hpaddr(af, name, &addrbuf, errp); 257 } 258#endif 259 if (inet_aton(name, (struct in_addr *)&addrbuf) == 1) { 260 if (af != AF_INET) { 261 if (MAPADDRENABLED(flags)) { 262 MAPADDR(&addrbuf, &addrbuf.in_addr); 263 } else { 264 *errp = HOST_NOT_FOUND; 265 return NULL; 266 } 267 } 268 return _hpaddr(af, name, &addrbuf, errp); 269 } 270 271 272 statp = __res_state(); 273 if ((statp->options & RES_INIT) == 0) { 274 if (res_ninit(statp) < 0) { 275 *errp = NETDB_INTERNAL; 276 return NULL; 277 } 278 } 279 280 options = statp->options; 281 statp->options &= ~RES_USE_INET6; 282 283 hp = gethostbyname2(name, af); 284 hp = _hpcopy(hp, errp); 285#ifdef INET6 286 if (af == AF_INET6) 287 hp = _hpreorder(hp); 288 289 if (af == AF_INET6 && ((flags & AI_ALL) || hp == NULL) && 290 MAPADDRENABLED(flags)) { 291 struct hostent *hp2 = gethostbyname2(name, AF_INET); 292 if (hp == NULL) 293 if (hp2 == NULL) 294 *errp = statp->res_h_errno; 295 else 296 hp = _hpmapv6(hp2, errp); 297 else { 298 if (hp2 && strcmp(hp->h_name, hp2->h_name) == 0) { 299 struct hostent *hpb = hp; 300 hp = _hpmerge(hpb, hp2, errp); 301 freehostent(hpb); 302 } 303 } 304 } 305#endif 306 307 if (hp == NULL) 308 *errp = statp->res_h_errno; 309 310 statp->options = options; 311 return _hpsort(hp, statp); 312} 313 314struct hostent * 315getipnodebyaddr(const void *src, size_t len, int af, int *errp) 316{ 317 struct hostent *hp; 318 res_state statp; 319 u_long options; 320 321#ifdef INET6 322 struct in6_addr addrbuf; 323#else 324 struct in_addr addrbuf; 325#endif 326 327 switch (af) { 328 case AF_INET: 329 if (len != sizeof(struct in_addr)) { 330 *errp = NO_RECOVERY; 331 return NULL; 332 } 333 if (rounddown2((long)src, sizeof(struct in_addr))) { 334 memcpy(&addrbuf, src, len); 335 src = &addrbuf; 336 } 337 if (((struct in_addr *)src)->s_addr == 0) 338 return NULL; 339 break; 340#ifdef INET6 341 case AF_INET6: 342 if (len != sizeof(struct in6_addr)) { 343 *errp = NO_RECOVERY; 344 return NULL; 345 } 346 if (rounddown2((long)src, sizeof(struct in6_addr) / 2)) { 347 /* XXX */ 348 memcpy(&addrbuf, src, len); 349 src = &addrbuf; 350 } 351 if (IN6_IS_ADDR_UNSPECIFIED((struct in6_addr *)src)) 352 return NULL; 353 if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)src) 354 || IN6_IS_ADDR_V4COMPAT((struct in6_addr *)src)) { 355 src = (char *)src + 356 (sizeof(struct in6_addr) - sizeof(struct in_addr)); 357 af = AF_INET; 358 len = sizeof(struct in_addr); 359 } 360 break; 361#endif 362 default: 363 *errp = NO_RECOVERY; 364 return NULL; 365 } 366 367 statp = __res_state(); 368 if ((statp->options & RES_INIT) == 0) { 369 if (res_ninit(statp) < 0) { 370 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 371 return NULL; 372 } 373 } 374 375 options = statp->options; 376 statp->options &= ~RES_USE_INET6; 377 378 hp = gethostbyaddr(src, len, af); 379 if (hp == NULL) 380 *errp = statp->res_h_errno; 381 382 statp->options = options; 383 return (_hpcopy(hp, errp)); 384} 385 386void 387freehostent(struct hostent *ptr) 388{ 389 free(ptr); 390} 391 392/* 393 * Private utility functions 394 */ 395 396/* 397 * _hpcopy: allocate and copy hostent structure 398 */ 399static struct hostent * 400_hpcopy(struct hostent *hp, int *errp) 401{ 402 struct hostent *nhp; 403 char *cp, **pp; 404 int size, addrsize; 405 int nalias = 0, naddr = 0; 406 int al_off; 407 int i; 408 409 if (hp == NULL) 410 return hp; 411 412 /* count size to be allocated */ 413 size = sizeof(struct hostent); 414 if (hp->h_name != NULL) 415 size += strlen(hp->h_name) + 1; 416 if ((pp = hp->h_aliases) != NULL) { 417 for (i = 0; *pp != NULL; i++, pp++) { 418 if (**pp != '\0') { 419 size += strlen(*pp) + 1; 420 nalias++; 421 } 422 } 423 } 424 /* adjust alignment */ 425 size = ALIGN(size); 426 al_off = size; 427 size += sizeof(char *) * (nalias + 1); 428 addrsize = ALIGN(hp->h_length); 429 if ((pp = hp->h_addr_list) != NULL) { 430 while (*pp++ != NULL) 431 naddr++; 432 } 433 size += addrsize * naddr; 434 size += sizeof(char *) * (naddr + 1); 435 436 /* copy */ 437 if ((nhp = (struct hostent *)malloc(size)) == NULL) { 438 *errp = TRY_AGAIN; 439 return NULL; 440 } 441 cp = (char *)&nhp[1]; 442 if (hp->h_name != NULL) { 443 nhp->h_name = cp; 444 strcpy(cp, hp->h_name); 445 cp += strlen(cp) + 1; 446 } else 447 nhp->h_name = NULL; 448 nhp->h_aliases = (char **)((char *)nhp + al_off); 449 if ((pp = hp->h_aliases) != NULL) { 450 for (i = 0; *pp != NULL; pp++) { 451 if (**pp != '\0') { 452 nhp->h_aliases[i++] = cp; 453 strcpy(cp, *pp); 454 cp += strlen(cp) + 1; 455 } 456 } 457 } 458 nhp->h_aliases[nalias] = NULL; 459 cp = (char *)&nhp->h_aliases[nalias + 1]; 460 nhp->h_addrtype = hp->h_addrtype; 461 nhp->h_length = hp->h_length; 462 nhp->h_addr_list = (char **)cp; 463 if ((pp = hp->h_addr_list) != NULL) { 464 cp = (char *)&nhp->h_addr_list[naddr + 1]; 465 for (i = 0; *pp != NULL; pp++) { 466 nhp->h_addr_list[i++] = cp; 467 memcpy(cp, *pp, hp->h_length); 468 cp += addrsize; 469 } 470 } 471 nhp->h_addr_list[naddr] = NULL; 472 return nhp; 473} 474 475/* 476 * _hpaddr: construct hostent structure with one address 477 */ 478static struct hostent * 479_hpaddr(int af, const char *name, void *addr, int *errp) 480{ 481 struct hostent *hp, hpbuf; 482 char *addrs[2]; 483 484 hp = &hpbuf; 485 hp->h_name = (char *)name; 486 hp->h_aliases = NULL; 487 hp->h_addrtype = af; 488 hp->h_length = ADDRLEN(af); 489 hp->h_addr_list = addrs; 490 addrs[0] = (char *)addr; 491 addrs[1] = NULL; 492 return (_hpcopy(hp, errp)); 493} 494 495#ifdef INET6 496/* 497 * _hpmerge: merge 2 hostent structure, arguments will be freed 498 */ 499static struct hostent * 500_hpmerge(struct hostent *hp1, struct hostent *hp2, int *errp) 501{ 502 int i, j; 503 int naddr, nalias; 504 char **pp; 505 struct hostent *hp, hpbuf; 506 char *aliases[MAXALIASES + 1], *addrs[MAXADDRS + 1]; 507 union inx_addr addrbuf[MAXADDRS]; 508 509 if (hp1 == NULL) 510 return _hpcopy(hp2, errp); 511 if (hp2 == NULL) 512 return _hpcopy(hp1, errp); 513 514#define HP(i) (i == 1 ? hp1 : hp2) 515 hp = &hpbuf; 516 hp->h_name = (hp1->h_name != NULL ? hp1->h_name : hp2->h_name); 517 hp->h_aliases = aliases; 518 nalias = 0; 519 for (i = 1; i <= 2; i++) { 520 if ((pp = HP(i)->h_aliases) == NULL) 521 continue; 522 for (; nalias < MAXALIASES && *pp != NULL; pp++) { 523 /* check duplicates */ 524 for (j = 0; j < nalias; j++) 525 if (strcasecmp(*pp, aliases[j]) == 0) 526 break; 527 if (j == nalias) 528 aliases[nalias++] = *pp; 529 } 530 } 531 aliases[nalias] = NULL; 532 if (hp1->h_length != hp2->h_length) { 533 hp->h_addrtype = AF_INET6; 534 hp->h_length = sizeof(struct in6_addr); 535 } else { 536 hp->h_addrtype = hp1->h_addrtype; 537 hp->h_length = hp1->h_length; 538 } 539 540 hp->h_addr_list = addrs; 541 naddr = 0; 542 for (i = 1; i <= 2; i++) { 543 if ((pp = HP(i)->h_addr_list) == NULL) 544 continue; 545 if (HP(i)->h_length == hp->h_length) { 546 while (naddr < MAXADDRS && *pp != NULL) 547 addrs[naddr++] = *pp++; 548 } else { 549 /* copy IPv4 addr as mapped IPv6 addr */ 550 while (naddr < MAXADDRS && *pp != NULL) { 551 MAPADDR(&addrbuf[naddr], *pp++); 552 addrs[naddr] = (char *)&addrbuf[naddr]; 553 naddr++; 554 } 555 } 556 } 557 addrs[naddr] = NULL; 558 return (_hpcopy(hp, errp)); 559} 560#endif 561 562/* 563 * _hpmapv6: convert IPv4 hostent into IPv4-mapped IPv6 addresses 564 */ 565#ifdef INET6 566static struct hostent * 567_hpmapv6(struct hostent *hp, int *errp) 568{ 569 struct hostent hp6; 570 571 if (hp == NULL) 572 return NULL; 573 if (hp->h_addrtype == AF_INET6) 574 return _hpcopy(hp, errp); 575 576 memset(&hp6, 0, sizeof(struct hostent)); 577 hp6.h_addrtype = AF_INET6; 578 hp6.h_length = sizeof(struct in6_addr); 579 return _hpmerge(&hp6, hp, errp); 580} 581#endif 582 583/* 584 * _hpsort: sort address by sortlist 585 */ 586static struct hostent * 587_hpsort(struct hostent *hp, res_state statp) 588{ 589 int i, j, n; 590 u_char *ap, *sp, *mp, **pp; 591 char t; 592 char order[MAXADDRS]; 593 int nsort = statp->nsort; 594 595 if (hp == NULL || hp->h_addr_list[1] == NULL || nsort == 0) 596 return hp; 597 for (i = 0; (ap = (u_char *)hp->h_addr_list[i]); i++) { 598 for (j = 0; j < nsort; j++) { 599#ifdef INET6 600 if (statp->_u._ext.ext->sort_list[j].af != 601 hp->h_addrtype) 602 continue; 603 sp = (u_char *)&statp->_u._ext.ext->sort_list[j].addr; 604 mp = (u_char *)&statp->_u._ext.ext->sort_list[j].mask; 605#else 606 sp = (u_char *)&statp->sort_list[j].addr; 607 mp = (u_char *)&statp->sort_list[j].mask; 608#endif 609 for (n = 0; n < hp->h_length; n++) { 610 if ((ap[n] & mp[n]) != sp[n]) 611 break; 612 } 613 if (n == hp->h_length) 614 break; 615 } 616 order[i] = j; 617 } 618 n = i; 619 pp = (u_char **)hp->h_addr_list; 620 for (i = 0; i < n - 1; i++) { 621 for (j = i + 1; j < n; j++) { 622 if (order[i] > order[j]) { 623 ap = pp[i]; 624 pp[i] = pp[j]; 625 pp[j] = ap; 626 t = order[i]; 627 order[i] = order[j]; 628 order[j] = t; 629 } 630 } 631 } 632 return hp; 633} 634 635#ifdef INET6 636/* 637 * _hpreorder: sort address by default address selection 638 */ 639static struct hostent * 640_hpreorder(struct hostent *hp) 641{ 642 struct hp_order *aio; 643 int i, n; 644 char *ap; 645 struct sockaddr *sa; 646 struct policyhead policyhead; 647 648 if (hp == NULL) 649 return hp; 650 651 switch (hp->h_addrtype) { 652 case AF_INET: 653#ifdef INET6 654 case AF_INET6: 655#endif 656 break; 657 default: 658 return hp; 659 } 660 661 /* count the number of addrinfo elements for sorting. */ 662 for (n = 0; hp->h_addr_list[n] != NULL; n++) 663 ; 664 665 /* 666 * If the number is small enough, we can skip the reordering process. 667 */ 668 if (n <= 1) 669 return hp; 670 671 /* allocate a temporary array for sort and initialization of it. */ 672 if ((aio = malloc(sizeof(*aio) * n)) == NULL) 673 return hp; /* give up reordering */ 674 memset(aio, 0, sizeof(*aio) * n); 675 676 /* retrieve address selection policy from the kernel */ 677 TAILQ_INIT(&policyhead); 678 if (!get_addrselectpolicy(&policyhead)) { 679 /* no policy is installed into kernel, we don't sort. */ 680 free(aio); 681 return hp; 682 } 683 684 for (i = 0; i < n; i++) { 685 ap = hp->h_addr_list[i]; 686 aio[i].aio_h_addr = ap; 687 sa = &aio[i].aio_sa; 688 switch (hp->h_addrtype) { 689 case AF_INET: 690 sa->sa_family = AF_INET; 691 sa->sa_len = sizeof(struct sockaddr_in); 692 memcpy(&((struct sockaddr_in *)sa)->sin_addr, ap, 693 sizeof(struct in_addr)); 694 break; 695#ifdef INET6 696 case AF_INET6: 697 if (IN6_IS_ADDR_V4MAPPED((struct in6_addr *)ap)) { 698 sa->sa_family = AF_INET; 699 sa->sa_len = sizeof(struct sockaddr_in); 700 memcpy(&((struct sockaddr_in *)sa)->sin_addr, 701 &ap[12], sizeof(struct in_addr)); 702 } else { 703 sa->sa_family = AF_INET6; 704 sa->sa_len = sizeof(struct sockaddr_in6); 705 memcpy(&((struct sockaddr_in6 *)sa)->sin6_addr, 706 ap, sizeof(struct in6_addr)); 707 } 708 break; 709#endif 710 } 711 aio[i].aio_dstscope = gai_addr2scopetype(sa); 712 aio[i].aio_dstpolicy = match_addrselectpolicy(sa, &policyhead); 713 set_source(&aio[i], &policyhead); 714 } 715 716 /* perform sorting. */ 717 qsort(aio, n, sizeof(*aio), comp_dst); 718 719 /* reorder the h_addr_list. */ 720 for (i = 0; i < n; i++) 721 hp->h_addr_list[i] = aio[i].aio_h_addr; 722 723 /* cleanup and return */ 724 free(aio); 725 free_addrselectpolicy(&policyhead); 726 return hp; 727} 728 729static int 730get_addrselectpolicy(struct policyhead *head) 731{ 732#ifdef INET6 733 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY }; 734 size_t l; 735 char *buf; 736 struct in6_addrpolicy *pol, *ep; 737 738 if (sysctl(mib, nitems(mib), NULL, &l, NULL, 0) < 0) 739 return (0); 740 if ((buf = malloc(l)) == NULL) 741 return (0); 742 if (sysctl(mib, nitems(mib), buf, &l, NULL, 0) < 0) { 743 free(buf); 744 return (0); 745 } 746 747 ep = (struct in6_addrpolicy *)(buf + l); 748 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) { 749 struct policyqueue *new; 750 751 if ((new = malloc(sizeof(*new))) == NULL) { 752 free_addrselectpolicy(head); /* make the list empty */ 753 break; 754 } 755 new->pc_policy = *pol; 756 TAILQ_INSERT_TAIL(head, new, pc_entry); 757 } 758 759 free(buf); 760 return (1); 761#else 762 return (0); 763#endif 764} 765 766static void 767free_addrselectpolicy(struct policyhead *head) 768{ 769 struct policyqueue *ent, *nent; 770 771 for (ent = TAILQ_FIRST(head); ent; ent = nent) { 772 nent = TAILQ_NEXT(ent, pc_entry); 773 TAILQ_REMOVE(head, ent, pc_entry); 774 free(ent); 775 } 776} 777 778static struct policyqueue * 779match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head) 780{ 781#ifdef INET6 782 struct policyqueue *ent, *bestent = NULL; 783 struct in6_addrpolicy *pol; 784 int matchlen, bestmatchlen = -1; 785 u_char *mp, *ep, *k, *p, m; 786 struct sockaddr_in6 key; 787 788 switch(addr->sa_family) { 789 case AF_INET6: 790 key = *(struct sockaddr_in6 *)addr; 791 break; 792 case AF_INET: 793 /* convert the address into IPv4-mapped IPv6 address. */ 794 memset(&key, 0, sizeof(key)); 795 key.sin6_family = AF_INET6; 796 key.sin6_len = sizeof(key); 797 _map_v4v6_address( 798 (char *)&((struct sockaddr_in *)addr)->sin_addr, 799 (char *)&key.sin6_addr); 800 break; 801 default: 802 return(NULL); 803 } 804 805 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) { 806 pol = &ent->pc_policy; 807 matchlen = 0; 808 809 mp = (u_char *)&pol->addrmask.sin6_addr; 810 ep = mp + 16; /* XXX: scope field? */ 811 k = (u_char *)&key.sin6_addr; 812 p = (u_char *)&pol->addr.sin6_addr; 813 for (; mp < ep && *mp; mp++, k++, p++) { 814 m = *mp; 815 if ((*k & m) != *p) 816 goto next; /* not match */ 817 if (m == 0xff) /* short cut for a typical case */ 818 matchlen += 8; 819 else { 820 while (m >= 0x80) { 821 matchlen++; 822 m <<= 1; 823 } 824 } 825 } 826 827 /* matched. check if this is better than the current best. */ 828 if (matchlen > bestmatchlen) { 829 bestent = ent; 830 bestmatchlen = matchlen; 831 } 832 833 next: 834 continue; 835 } 836 837 return(bestent); 838#else 839 return(NULL); 840#endif 841 842} 843 844static void 845set_source(struct hp_order *aio, struct policyhead *ph) 846{ 847 struct sockaddr_storage ss = aio->aio_un.aiou_ss; 848 socklen_t srclen; 849 int s; 850 851 /* set unspec ("no source is available"), just in case */ 852 aio->aio_srcsa.sa_family = AF_UNSPEC; 853 aio->aio_srcscope = -1; 854 855 switch(ss.ss_family) { 856 case AF_INET: 857 ((struct sockaddr_in *)&ss)->sin_port = htons(1); 858 break; 859#ifdef INET6 860 case AF_INET6: 861 ((struct sockaddr_in6 *)&ss)->sin6_port = htons(1); 862 break; 863#endif 864 default: /* ignore unsupported AFs explicitly */ 865 return; 866 } 867 868 /* open a socket to get the source address for the given dst */ 869 if ((s = _socket(ss.ss_family, SOCK_DGRAM | SOCK_CLOEXEC, 870 IPPROTO_UDP)) < 0) 871 return; /* give up */ 872 if (_connect(s, (struct sockaddr *)&ss, ss.ss_len) < 0) 873 goto cleanup; 874 srclen = ss.ss_len; 875 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) { 876 aio->aio_srcsa.sa_family = AF_UNSPEC; 877 goto cleanup; 878 } 879 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa); 880 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph); 881 aio->aio_matchlen = matchlen(&aio->aio_srcsa, (struct sockaddr *)&ss); 882#ifdef INET6 883 if (ss.ss_family == AF_INET6) { 884 struct in6_ifreq ifr6; 885 u_int32_t flags6; 886 887 memset(&ifr6, 0, sizeof(ifr6)); 888 memcpy(&ifr6.ifr_addr, &ss, ss.ss_len); 889 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) { 890 flags6 = ifr6.ifr_ifru.ifru_flags6; 891 if ((flags6 & IN6_IFF_DEPRECATED)) 892 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED; 893 } 894 } 895#endif 896 897 cleanup: 898 _close(s); 899 return; 900} 901 902static int 903matchlen(struct sockaddr *src, struct sockaddr *dst) 904{ 905 int match = 0; 906 u_char *s, *d; 907 u_char *lim, r; 908 int addrlen; 909 910 switch (src->sa_family) { 911#ifdef INET6 912 case AF_INET6: 913 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr; 914 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr; 915 addrlen = sizeof(struct in6_addr); 916 lim = s + addrlen; 917 break; 918#endif 919 case AF_INET: 920 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr; 921 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr; 922 addrlen = sizeof(struct in_addr); 923 lim = s + addrlen; 924 break; 925 default: 926 return(0); 927 } 928 929 while (s < lim) 930 if ((r = (*d++ ^ *s++)) != 0) { 931 while (r < addrlen * 8) { 932 match++; 933 r <<= 1; 934 } 935 break; 936 } else 937 match += 8; 938 return(match); 939} 940 941static int 942comp_dst(const void *arg1, const void *arg2) 943{ 944 const struct hp_order *dst1 = arg1, *dst2 = arg2; 945 946 /* 947 * Rule 1: Avoid unusable destinations. 948 * XXX: we currently do not consider if an appropriate route exists. 949 */ 950 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 951 dst2->aio_srcsa.sa_family == AF_UNSPEC) { 952 return(-1); 953 } 954 if (dst1->aio_srcsa.sa_family == AF_UNSPEC && 955 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 956 return(1); 957 } 958 959 /* Rule 2: Prefer matching scope. */ 960 if (dst1->aio_dstscope == dst1->aio_srcscope && 961 dst2->aio_dstscope != dst2->aio_srcscope) { 962 return(-1); 963 } 964 if (dst1->aio_dstscope != dst1->aio_srcscope && 965 dst2->aio_dstscope == dst2->aio_srcscope) { 966 return(1); 967 } 968 969 /* Rule 3: Avoid deprecated addresses. */ 970 if (dst1->aio_srcsa.sa_family != AF_UNSPEC && 971 dst2->aio_srcsa.sa_family != AF_UNSPEC) { 972 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 973 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 974 return(-1); 975 } 976 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) && 977 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) { 978 return(1); 979 } 980 } 981 982 /* Rule 4: Prefer home addresses. */ 983 /* XXX: not implemented yet */ 984 985 /* Rule 5: Prefer matching label. */ 986#ifdef INET6 987 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy && 988 dst1->aio_srcpolicy->pc_policy.label == 989 dst1->aio_dstpolicy->pc_policy.label && 990 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL || 991 dst2->aio_srcpolicy->pc_policy.label != 992 dst2->aio_dstpolicy->pc_policy.label)) { 993 return(-1); 994 } 995 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy && 996 dst2->aio_srcpolicy->pc_policy.label == 997 dst2->aio_dstpolicy->pc_policy.label && 998 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL || 999 dst1->aio_srcpolicy->pc_policy.label != 1000 dst1->aio_dstpolicy->pc_policy.label)) { 1001 return(1); 1002 } 1003#endif 1004 1005 /* Rule 6: Prefer higher precedence. */ 1006#ifdef INET6 1007 if (dst1->aio_dstpolicy && 1008 (dst2->aio_dstpolicy == NULL || 1009 dst1->aio_dstpolicy->pc_policy.preced > 1010 dst2->aio_dstpolicy->pc_policy.preced)) { 1011 return(-1); 1012 } 1013 if (dst2->aio_dstpolicy && 1014 (dst1->aio_dstpolicy == NULL || 1015 dst2->aio_dstpolicy->pc_policy.preced > 1016 dst1->aio_dstpolicy->pc_policy.preced)) { 1017 return(1); 1018 } 1019#endif 1020 1021 /* Rule 7: Prefer native transport. */ 1022 /* XXX: not implemented yet */ 1023 1024 /* Rule 8: Prefer smaller scope. */ 1025 if (dst1->aio_dstscope >= 0 && 1026 dst1->aio_dstscope < dst2->aio_dstscope) { 1027 return(-1); 1028 } 1029 if (dst2->aio_dstscope >= 0 && 1030 dst2->aio_dstscope < dst1->aio_dstscope) { 1031 return(1); 1032 } 1033 1034 /* 1035 * Rule 9: Use longest matching prefix. 1036 * We compare the match length in a same AF only. 1037 */ 1038 if (dst1->aio_sa.sa_family == dst2->aio_sa.sa_family) { 1039 if (dst1->aio_matchlen > dst2->aio_matchlen) { 1040 return(-1); 1041 } 1042 if (dst1->aio_matchlen < dst2->aio_matchlen) { 1043 return(1); 1044 } 1045 } 1046 1047 /* Rule 10: Otherwise, leave the order unchanged. */ 1048 return(-1); 1049} 1050 1051/* 1052 * Copy from scope.c. 1053 * XXX: we should standardize the functions and link them as standard 1054 * library. 1055 */ 1056static int 1057gai_addr2scopetype(struct sockaddr *sa) 1058{ 1059#ifdef INET6 1060 struct sockaddr_in6 *sa6; 1061#endif 1062 struct sockaddr_in *sa4; 1063 1064 switch(sa->sa_family) { 1065#ifdef INET6 1066 case AF_INET6: 1067 sa6 = (struct sockaddr_in6 *)sa; 1068 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) { 1069 /* just use the scope field of the multicast address */ 1070 return(sa6->sin6_addr.s6_addr[2] & 0x0f); 1071 } 1072 /* 1073 * Unicast addresses: map scope type to corresponding scope 1074 * value defined for multcast addresses. 1075 * XXX: hardcoded scope type values are bad... 1076 */ 1077 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr)) 1078 return(1); /* node local scope */ 1079 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 1080 return(2); /* link-local scope */ 1081 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr)) 1082 return(5); /* site-local scope */ 1083 return(14); /* global scope */ 1084 break; 1085#endif 1086 case AF_INET: 1087 /* 1088 * IPv4 pseudo scoping according to RFC 3484. 1089 */ 1090 sa4 = (struct sockaddr_in *)sa; 1091 /* IPv4 autoconfiguration addresses have link-local scope. */ 1092 if (((u_char *)&sa4->sin_addr)[0] == 169 && 1093 ((u_char *)&sa4->sin_addr)[1] == 254) 1094 return(2); 1095 /* Private addresses have site-local scope. */ 1096 if (((u_char *)&sa4->sin_addr)[0] == 10 || 1097 (((u_char *)&sa4->sin_addr)[0] == 172 && 1098 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) || 1099 (((u_char *)&sa4->sin_addr)[0] == 192 && 1100 ((u_char *)&sa4->sin_addr)[1] == 168)) 1101 return(14); /* XXX: It should be 5 unless NAT */ 1102 /* Loopback addresses have link-local scope. */ 1103 if (((u_char *)&sa4->sin_addr)[0] == 127) 1104 return(2); 1105 return(14); 1106 break; 1107 default: 1108 errno = EAFNOSUPPORT; /* is this a good error? */ 1109 return(-1); 1110 } 1111} 1112#endif 1113