1 /* $FreeBSD: src/lib/libc/net/getaddrinfo.c,v 1.9.2.14 2002/11/08 17:49:31 ume Exp $ */
2 /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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
34 * "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator.
36 * Issues to be discussed:
37 * - Thread safe-ness must be checked.
38 * - Return values. There are nonstandard return values defined and used
39 * in the source code. This is because RFC2553 is silent about which error
40 * code must be returned for which situation.
41 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is
42 * invalid. current code - SEGV on freeaddrinfo(NULL)
45 * - The code filters out AFs that are not supported by the kernel,
46 * when globbing NULL hostname (to loopback, or wildcard). Is it the right
47 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG
49 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague.
50 * (1) what should we do against numeric hostname (2) what should we do
51 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready?
52 * non-loopback address configured? global address configured?
54 * OS specific notes for netbsd/openbsd/freebsd4/bsdi4:
55 * - To avoid search order issue, we have a big amount of code duplicate
56 * from gethnamaddr.c and some other places. The issues that there's no
57 * lower layer function to lookup "IPv4 or IPv6" record. Calling
58 * gethostbyname2 from getaddrinfo will end up in wrong search order, as
61 * OS specific notes for freebsd4:
62 * - FreeBSD supported $GAI. The code does not.
63 * - FreeBSD allowed classful IPv4 numeric (127.1), the code does not.
66 #include <sys/types.h>
67 #include <sys/param.h>
68 #include <sys/socket.h>
70 #include <netinet/in.h>
71 #include <arpa/inet.h>
72 #include <arpa/nameser.h>
83 #include "res_config.h"
89 #if defined(__KAME__) && defined(INET6)
98 static const char in_addrany[] = { 0, 0, 0, 0 };
99 static const char in_loopback[] = { 127, 0, 0, 1 };
101 static const char in6_addrany[] = {
102 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
104 static const char in6_loopback[] = {
105 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
109 static const struct afd {
114 const char *a_addrany;
115 const char *a_loopback;
120 {PF_INET6, sizeof(struct in6_addr),
121 sizeof(struct sockaddr_in6),
122 offsetof(struct sockaddr_in6, sin6_addr),
123 in6_addrany, in6_loopback, 1},
128 {PF_INET, sizeof(struct in_addr),
129 sizeof(struct sockaddr_in),
130 offsetof(struct sockaddr_in, sin_addr),
131 in_addrany, in_loopback, 0},
132 {0, 0, 0, 0, NULL, NULL, 0},
139 const char *e_protostr;
141 #define WILD_AF(ex) ((ex)->e_wild & 0x01)
142 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02)
143 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04)
146 static const struct explore explore[] = {
148 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 },
151 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
152 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
153 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
155 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
156 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
157 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
158 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
159 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
160 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 },
161 { -1, 0, 0, NULL, 0 },
170 #define MAXPACKET (64*1024)
174 u_char buf[MAXPACKET];
178 struct res_target *next;
179 const char *name; /* domain name */
180 int qclass, qtype; /* class and type of query */
181 u_char *answer; /* buffer to put answer */
182 int anslen; /* size of answer buffer */
183 int n; /* result length */
186 static int str_isnumber __P((const char *));
187 static int explore_fqdn __P((const struct addrinfo *, const char *,
188 const char *, struct addrinfo **));
189 static int explore_null __P((const struct addrinfo *,
190 const char *, struct addrinfo **));
191 static int explore_numeric __P((const struct addrinfo *, const char *,
192 const char *, struct addrinfo **));
193 static int explore_numeric_scope __P((const struct addrinfo *, const char *,
194 const char *, struct addrinfo **));
195 static int get_canonname __P((const struct addrinfo *,
196 struct addrinfo *, const char *));
197 static struct addrinfo *get_ai __P((const struct addrinfo *,
198 const struct afd *, const char *));
199 static int get_portmatch __P((const struct addrinfo *, const char *));
200 static int get_port __P((struct addrinfo *, const char *, int));
201 static const struct afd *find_afd __P((int));
202 static int addrconfig __P((struct addrinfo *));
204 static int ip6_str2scopeid __P((char *, struct sockaddr_in6 *, u_int32_t *));
207 static struct addrinfo *getanswer __P((const querybuf *, int, const char *,
208 int, const struct addrinfo *));
209 static int _dns_getaddrinfo __P((const struct addrinfo *, const char *,
210 struct addrinfo **));
211 static struct addrinfo *_gethtent __P((FILE *fp, const char *,
212 const struct addrinfo *));
213 static int _files_getaddrinfo __P((const struct addrinfo *, const char *,
214 struct addrinfo **));
216 static int _nis_getaddrinfo __P((const struct addrinfo *, const char *,
217 struct addrinfo **));
220 static int res_queryN __P((const char *, struct res_target *));
221 static int res_searchN __P((const char *, struct res_target *));
222 static int res_querydomainN __P((const char *, const char *,
223 struct res_target *));
225 static char *ai_errlist[] = {
227 "Address family for hostname not supported", /* EAI_ADDRFAMILY */
228 "Temporary failure in name resolution", /* EAI_AGAIN */
229 "Invalid value for ai_flags", /* EAI_BADFLAGS */
230 "Non-recoverable failure in name resolution", /* EAI_FAIL */
231 "ai_family not supported", /* EAI_FAMILY */
232 "Memory allocation failure", /* EAI_MEMORY */
233 "No address associated with hostname", /* EAI_NODATA */
234 "hostname nor servname provided, or not known", /* EAI_NONAME */
235 "servname not supported for ai_socktype", /* EAI_SERVICE */
236 "ai_socktype not supported", /* EAI_SOCKTYPE */
237 "System error returned in errno", /* EAI_SYSTEM */
238 "Invalid value for hints", /* EAI_BADHINTS */
239 "Resolved protocol is unknown", /* EAI_PROTOCOL */
240 "Unknown error", /* EAI_MAX */
244 * Select order host function.
246 #define MAXHOSTCONF 4
249 # define HOSTCONF "/etc/host.conf"
250 #endif /* !HOSTCONF */
253 int (*byname)(const struct addrinfo *, const char *,
258 static struct _hostconf _hostconf[MAXHOSTCONF] = {
266 static int _hostconf_init_done;
267 static void _hostconf_init(void);
269 /* Make getaddrinfo() thread-safe in libc for use with kernel threads. */
270 #include "libc_private.h"
271 #include "spinlock.h"
273 * XXX: Our res_*() is not thread-safe. So, we share lock between
274 * getaddrinfo() and getipnodeby*(). Still, we cannot use
275 * getaddrinfo() and getipnodeby*() in conjunction with other
276 * functions which call res_*().
278 spinlock_t __getaddrinfo_thread_lock = _SPINLOCK_INITIALIZER;
279 #define THREAD_LOCK() \
280 if (__isthreaded) _SPINLOCK(&__getaddrinfo_thread_lock);
281 #define THREAD_UNLOCK() \
282 if (__isthreaded) _SPINUNLOCK(&__getaddrinfo_thread_lock);
284 /* XXX macros that make external reference is BAD. */
286 #define GET_AI(ai, afd, addr) \
288 /* external reference: pai, error, and label free */ \
289 (ai) = get_ai(pai, (afd), (addr)); \
290 if ((ai) == NULL) { \
291 error = EAI_MEMORY; \
294 } while (/*CONSTCOND*/0)
296 #define GET_PORT(ai, serv) \
298 /* external reference: error and label free */ \
299 error = get_port((ai), (serv), 0); \
302 } while (/*CONSTCOND*/0)
304 #define GET_CANONNAME(ai, str) \
306 /* external reference: pai, error and label free */ \
307 error = get_canonname(pai, (ai), (str)); \
310 } while (/*CONSTCOND*/0)
314 /* external reference: error, and label bad */ \
318 } while (/*CONSTCOND*/0)
320 #define MATCH_FAMILY(x, y, w) \
321 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
322 #define MATCH(x, y, w) \
323 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
329 if (ecode < 0 || ecode > EAI_MAX)
331 return ai_errlist[ecode];
338 struct addrinfo *next;
342 if (ai->ai_canonname)
343 free(ai->ai_canonname);
344 /* no need to free(ai->ai_addr) */
360 (void)strtoul(p, &ep, 10);
361 if (errno == 0 && ep && *ep == '\0')
368 getaddrinfo(hostname, servname, hints, res)
369 const char *hostname, *servname;
370 const struct addrinfo *hints;
371 struct addrinfo **res;
373 struct addrinfo sentinel;
374 struct addrinfo *cur;
378 struct addrinfo *pai;
379 const struct explore *ex;
381 memset(&sentinel, 0, sizeof(sentinel));
385 pai->ai_family = PF_UNSPEC;
386 pai->ai_socktype = ANY;
387 pai->ai_protocol = ANY;
389 pai->ai_canonname = NULL;
393 if (hostname == NULL && servname == NULL)
396 /* error check for hints */
397 if (hints->ai_addrlen || hints->ai_canonname ||
398 hints->ai_addr || hints->ai_next)
399 ERR(EAI_BADHINTS); /* xxx */
400 if (hints->ai_flags & ~AI_MASK)
402 switch (hints->ai_family) {
412 memcpy(pai, hints, sizeof(*pai));
415 * if both socktype/protocol are specified, check if they
416 * are meaningful combination.
418 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
419 for (ex = explore; ex->e_af >= 0; ex++) {
420 if (pai->ai_family != ex->e_af)
422 if (ex->e_socktype == ANY)
424 if (ex->e_protocol == ANY)
426 if (pai->ai_socktype == ex->e_socktype &&
427 pai->ai_protocol != ex->e_protocol) {
435 * post-2553: AI_ALL and AI_V4MAPPED are effective only against
436 * AF_INET6 query. They need to be ignored if specified in other
439 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) {
441 case AI_ALL | AI_V4MAPPED:
442 if (pai->ai_family != AF_INET6)
443 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED);
450 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED);
456 * check for special cases. (1) numeric servname is disallowed if
457 * socktype/protocol are left unspecified. (2) servname is disallowed
458 * for raw and other inet{,6} sockets.
460 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
462 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
465 ai0 = *pai; /* backup *pai */
467 if (pai->ai_family == PF_UNSPEC) {
469 pai->ai_family = PF_INET6;
471 pai->ai_family = PF_INET;
474 error = get_portmatch(pai, servname);
483 /* NULL hostname, or numeric hostname */
484 for (ex = explore; ex->e_af >= 0; ex++) {
487 /* PF_UNSPEC entries are prepared for DNS queries only */
488 if (ex->e_af == PF_UNSPEC)
491 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
493 if (!MATCH(pai->ai_socktype, ex->e_socktype,
496 if (!MATCH(pai->ai_protocol, ex->e_protocol,
500 if (pai->ai_family == PF_UNSPEC)
501 pai->ai_family = ex->e_af;
502 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
503 pai->ai_socktype = ex->e_socktype;
504 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
505 pai->ai_protocol = ex->e_protocol;
507 if (hostname == NULL)
508 error = explore_null(pai, servname, &cur->ai_next);
510 error = explore_numeric_scope(pai, hostname, servname,
516 while (cur && cur->ai_next)
522 * If numreic representation of AF1 can be interpreted as FQDN
523 * representation of AF2, we need to think again about the code below.
525 if (sentinel.ai_next)
528 if (pai->ai_flags & AI_NUMERICHOST)
530 if (hostname == NULL)
533 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0))
537 * hostname as alphabetical name.
538 * we would like to prefer AF_INET6 than AF_INET, so we'll make a
541 for (ex = explore; ex->e_af >= 0; ex++) {
544 /* require exact match for family field */
545 if (pai->ai_family != ex->e_af)
548 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) {
551 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) {
555 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
556 pai->ai_socktype = ex->e_socktype;
557 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
558 pai->ai_protocol = ex->e_protocol;
560 error = explore_fqdn(pai, hostname, servname, &cur->ai_next);
562 while (cur && cur->ai_next)
567 if (sentinel.ai_next)
573 if (sentinel.ai_next) {
575 *res = sentinel.ai_next;
582 if (sentinel.ai_next)
583 freeaddrinfo(sentinel.ai_next);
593 static const char sep[] = "# \t\n";
596 for (p = *pp; (c = *p) != '\0'; p++) {
597 for (sp = sep; *sp != '\0'; sp++) {
602 p[1] = '\0'; /* ignore rest of line */
614 if (ret == NULL || *ret == '\0')
620 * Initialize hostconf structure.
631 _hostconf_init_done = 1;
634 if ((fp = fopen(p, "r")) == NULL)
636 while (n < MAXHOSTCONF && fgets(buf, sizeof(buf), fp)) {
638 if ((p = _hgetword(&line)) == NULL)
641 if (strcmp(p, "hosts") == 0
642 || strcmp(p, "local") == 0
643 || strcmp(p, "file") == 0
644 || strcmp(p, "files") == 0)
645 _hostconf[n++].byname = _files_getaddrinfo;
646 else if (strcmp(p, "dns") == 0
647 || strcmp(p, "bind") == 0)
648 _hostconf[n++].byname = _dns_getaddrinfo;
650 else if (strcmp(p, "nis") == 0)
651 _hostconf[n++].byname = _nis_getaddrinfo;
653 } while ((p = _hgetword(&line)) != NULL);
657 /* no keyword found. do not change default configuration */
660 for (; n < MAXHOSTCONF; n++)
661 _hostconf[n].byname = NULL;
665 * FQDN hostname, DNS lookup
668 explore_fqdn(pai, hostname, servname, res)
669 const struct addrinfo *pai;
670 const char *hostname;
671 const char *servname;
672 struct addrinfo **res;
674 struct addrinfo *result;
675 struct addrinfo *cur;
684 * if the servname does not match socktype/protocol, ignore it.
686 if (get_portmatch(pai, servname) != 0) {
691 if (!_hostconf_init_done)
694 for (i = 0; i < MAXHOSTCONF; i++) {
695 if (!_hostconf[i].byname)
697 error = (*_hostconf[i].byname)(pai, hostname, &result);
700 for (cur = result; cur; cur = cur->ai_next) {
701 GET_PORT(cur, servname);
702 /* canonname should be filled already */
712 freeaddrinfo(result);
718 * passive socket -> anyaddr (0.0.0.0 or ::)
719 * non-passive socket -> localhost (127.0.0.1 or ::1)
722 explore_null(pai, servname, res)
723 const struct addrinfo *pai;
724 const char *servname;
725 struct addrinfo **res;
728 const struct afd *afd;
729 struct addrinfo *cur;
730 struct addrinfo sentinel;
734 sentinel.ai_next = NULL;
738 * filter out AFs that are not supported by the kernel
741 s = socket(pai->ai_family, SOCK_DGRAM, 0);
749 * if the servname does not match socktype/protocol, ignore it.
751 if (get_portmatch(pai, servname) != 0)
754 afd = find_afd(pai->ai_family);
758 if (pai->ai_flags & AI_PASSIVE) {
759 GET_AI(cur->ai_next, afd, afd->a_addrany);
761 * GET_CANONNAME(cur->ai_next, "anyaddr");
763 GET_PORT(cur->ai_next, servname);
765 GET_AI(cur->ai_next, afd, afd->a_loopback);
767 * GET_CANONNAME(cur->ai_next, "localhost");
769 GET_PORT(cur->ai_next, servname);
773 *res = sentinel.ai_next;
777 if (sentinel.ai_next)
778 freeaddrinfo(sentinel.ai_next);
786 explore_numeric(pai, hostname, servname, res)
787 const struct addrinfo *pai;
788 const char *hostname;
789 const char *servname;
790 struct addrinfo **res;
792 const struct afd *afd;
793 struct addrinfo *cur;
794 struct addrinfo sentinel;
799 sentinel.ai_next = NULL;
803 * if the servname does not match socktype/protocol, ignore it.
805 if (get_portmatch(pai, servname) != 0)
808 afd = find_afd(pai->ai_family);
813 #if 1 /*X/Open spec*/
815 if (inet_aton(hostname, (struct in_addr *)pton) == 1) {
816 if (pai->ai_family == afd->a_af ||
817 pai->ai_family == PF_UNSPEC /*?*/) {
818 GET_AI(cur->ai_next, afd, pton);
819 GET_PORT(cur->ai_next, servname);
820 while (cur && cur->ai_next)
823 ERR(EAI_FAMILY); /*xxx*/
828 if (inet_pton(afd->a_af, hostname, pton) == 1) {
829 if (pai->ai_family == afd->a_af ||
830 pai->ai_family == PF_UNSPEC /*?*/) {
831 GET_AI(cur->ai_next, afd, pton);
832 GET_PORT(cur->ai_next, servname);
833 while (cur && cur->ai_next)
836 ERR(EAI_FAMILY); /* XXX */
841 *res = sentinel.ai_next;
846 if (sentinel.ai_next)
847 freeaddrinfo(sentinel.ai_next);
852 * numeric hostname with scope
855 explore_numeric_scope(pai, hostname, servname, res)
856 const struct addrinfo *pai;
857 const char *hostname;
858 const char *servname;
859 struct addrinfo **res;
861 #if !defined(SCOPE_DELIMITER) || !defined(INET6)
862 return explore_numeric(pai, hostname, servname, res);
864 const struct afd *afd;
865 struct addrinfo *cur;
867 char *cp, *hostname2 = NULL, *scope, *addr;
868 struct sockaddr_in6 *sin6;
871 * if the servname does not match socktype/protocol, ignore it.
873 if (get_portmatch(pai, servname) != 0)
876 afd = find_afd(pai->ai_family);
880 return explore_numeric(pai, hostname, servname, res);
882 cp = strchr(hostname, SCOPE_DELIMITER);
884 return explore_numeric(pai, hostname, servname, res);
887 * Handle special case of <scoped_address><delimiter><scope id>
889 hostname2 = strdup(hostname);
890 if (hostname2 == NULL)
892 /* terminate at the delimiter */
893 hostname2[cp - hostname] = '\0';
897 error = explore_numeric(pai, addr, servname, res);
901 for (cur = *res; cur; cur = cur->ai_next) {
902 if (cur->ai_family != AF_INET6)
904 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
905 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) {
907 return(EAI_NODATA); /* XXX: is return OK? */
909 sin6->sin6_scope_id = scopeid;
920 get_canonname(pai, ai, str)
921 const struct addrinfo *pai;
925 if ((pai->ai_flags & AI_CANONNAME) != 0) {
926 ai->ai_canonname = (char *)malloc(strlen(str) + 1);
927 if (ai->ai_canonname == NULL)
929 strlcpy(ai->ai_canonname, str, strlen(str) + 1);
934 static struct addrinfo *
935 get_ai(pai, afd, addr)
936 const struct addrinfo *pai;
937 const struct afd *afd;
943 struct in6_addr faith_prefix;
950 * Transfrom an IPv4 addr into a special IPv6 addr format for
951 * IPv6->IPv4 translation gateway. (only TCP is supported now)
953 * +-----------------------------------+------------+
954 * | faith prefix part (12 bytes) | embedded |
955 * | | IPv4 addr part (4 bytes)
956 * +-----------------------------------+------------+
958 * faith prefix part is specified as ascii IPv6 addr format
959 * in environmental variable GAI.
960 * For FAITH to work correctly, routing to faith prefix must be
961 * setup toward a machine where a FAITH daemon operates.
962 * Also, the machine must enable some mechanizm
963 * (e.g. faith interface hack) to divert those packet with
964 * faith prefixed destination addr to user-land FAITH daemon.
966 fp_str = getenv("GAI");
967 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 &&
968 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) {
972 memcpy(&v4a, addr, sizeof v4a);
973 v4a_top = v4a >> IN_CLASSA_NSHIFT;
974 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) &&
975 v4a_top != 0 && v4a != IN_LOOPBACKNET) {
976 afd = &afdl[N_INET6];
977 memcpy(&faith_prefix.s6_addr[12], addr,
978 sizeof(struct in_addr));
984 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo)
989 memcpy(ai, pai, sizeof(struct addrinfo));
990 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
991 memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
992 ai->ai_addr->sa_len = afd->a_socklen;
993 ai->ai_addrlen = afd->a_socklen;
994 ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
995 p = (char *)(ai->ai_addr);
998 memcpy(p + afd->a_off, &faith_prefix, afd->a_addrlen);
1001 memcpy(p + afd->a_off, addr, afd->a_addrlen);
1007 get_portmatch(ai, servname)
1008 const struct addrinfo *ai;
1009 const char *servname;
1012 /* get_port does not touch first argument. when matchonly == 1. */
1013 /* LINTED const cast */
1014 return get_port((struct addrinfo *)ai, servname, 1);
1018 get_port(ai, servname, matchonly)
1019 struct addrinfo *ai;
1020 const char *servname;
1028 if (servname == NULL)
1030 switch (ai->ai_family) {
1040 switch (ai->ai_socktype) {
1051 return EAI_SOCKTYPE;
1054 if (str_isnumber(servname)) {
1057 port = atoi(servname);
1058 if (port < 0 || port > 65535)
1062 switch (ai->ai_socktype) {
1074 if ((sp = getservbyname(servname, proto)) == NULL)
1080 switch (ai->ai_family) {
1082 ((struct sockaddr_in *)(void *)
1083 ai->ai_addr)->sin_port = port;
1087 ((struct sockaddr_in6 *)(void *)
1088 ai->ai_addr)->sin6_port = port;
1097 static const struct afd *
1101 const struct afd *afd;
1103 if (af == PF_UNSPEC)
1105 for (afd = afdl; afd->a_af; afd++) {
1106 if (afd->a_af == af)
1113 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend
1114 * will take care of it.
1115 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure
1116 * if the code is right or not.
1118 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with
1123 struct addrinfo *pai;
1129 * Note that implementation dependent test for address
1130 * configuration should be done everytime called
1131 * (or apropriate interval),
1132 * because addresses will be dynamically assigned or deleted.
1134 af = pai->ai_family;
1135 if (af == AF_UNSPEC) {
1136 if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
1140 if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
1147 if (af != AF_UNSPEC) {
1148 if ((s = socket(af, SOCK_DGRAM, 0)) < 0)
1152 pai->ai_family = af;
1157 /* convert a string to a scope identifier. XXX: IPv6 specific */
1159 ip6_str2scopeid(scope, sin6, scopeid)
1161 struct sockaddr_in6 *sin6;
1165 struct in6_addr *a6;
1168 a6 = &sin6->sin6_addr;
1170 /* empty scopeid portion is invalid */
1174 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) {
1176 * We currently assume a one-to-one mapping between links
1177 * and interfaces, so we simply use interface indices for
1178 * like-local scopes.
1180 *scopeid = if_nametoindex(scope);
1186 /* still unclear about literal, allow numeric only - placeholder */
1187 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
1189 if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
1192 goto trynumeric; /* global */
1194 /* try to convert to a numeric id as a last resort */
1197 lscopeid = strtoul(scope, &ep, 10);
1198 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL);
1199 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid)
1208 struct addrinfo *ai;
1213 addr4sort(struct addrinfo *sentinel)
1215 struct addrinfo *ai;
1216 struct addr_ptr *addrs, addr;
1217 struct sockaddr_in *sin;
1224 for (ai = sentinel->ai_next; ai; ai = ai->ai_next)
1227 return 0; /* We don't need sorting. */
1228 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL)
1231 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) {
1232 sin = (struct sockaddr_in *)ai->ai_addr;
1233 for (j = 0; (unsigned)j < _res.nsort; j++) {
1234 if (_res.sort_list[j].addr.s_addr ==
1235 (sin->sin_addr.s_addr & _res.sort_list[j].mask))
1240 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval)
1249 while (needsort < naddrs) {
1250 for (j = needsort - 1; j >= 0; j--) {
1251 if (addrs[j].aval > addrs[j+1].aval) {
1253 addrs[j] = addrs[j + 1];
1254 addrs[j + 1] = addr;
1262 for (i = 0; i < naddrs; ++i) {
1263 ai->ai_next = addrs[i].ai;
1270 #endif /*RESOLVSORT*/
1273 static const char AskedForGot[] =
1274 "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
1277 static struct addrinfo *
1278 getanswer(answer, anslen, qname, qtype, pai)
1279 const querybuf *answer;
1283 const struct addrinfo *pai;
1285 struct addrinfo sentinel, *cur;
1287 const struct afd *afd;
1294 int type, class, ancount, qdcount;
1295 int haveanswer, had_error;
1296 char tbuf[MAXDNAME];
1297 int (*name_ok) __P((const char *));
1298 char hostbuf[8*1024];
1300 memset(&sentinel, 0, sizeof(sentinel));
1304 eom = answer->buf + anslen;
1308 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/
1312 return (NULL); /* XXX should be abort(); */
1315 * find first satisfactory answer
1318 ancount = ntohs(hp->ancount);
1319 qdcount = ntohs(hp->qdcount);
1321 ep = hostbuf + sizeof hostbuf;
1322 cp = answer->buf + HFIXEDSZ;
1324 h_errno = NO_RECOVERY;
1327 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1328 if ((n < 0) || !(*name_ok)(bp)) {
1329 h_errno = NO_RECOVERY;
1333 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
1334 /* res_send() has already verified that the query name is the
1335 * same as the one we sent; this just gets the expanded name
1336 * (i.e., with the succeeding search-domain tacked on).
1338 n = strlen(bp) + 1; /* for the \0 */
1339 if (n >= MAXHOSTNAMELEN) {
1340 h_errno = NO_RECOVERY;
1345 /* The qname can be abbreviated, but h_name is now absolute. */
1350 while (ancount-- > 0 && cp < eom && !had_error) {
1351 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1352 if ((n < 0) || !(*name_ok)(bp)) {
1357 type = _getshort(cp);
1358 cp += INT16SZ; /* type */
1359 class = _getshort(cp);
1360 cp += INT16SZ + INT32SZ; /* class, TTL */
1362 cp += INT16SZ; /* len */
1363 if (class != C_IN) {
1364 /* XXX - debug? syslog? */
1366 continue; /* XXX - had_error++ ? */
1368 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
1370 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
1371 if ((n < 0) || !(*name_ok)(tbuf)) {
1376 /* Get canonical name. */
1377 n = strlen(tbuf) + 1; /* for the \0 */
1378 if (n > ep - bp || n >= MAXHOSTNAMELEN) {
1382 strlcpy(bp, tbuf, ep - bp);
1387 if (qtype == T_ANY) {
1388 if (!(type == T_A || type == T_AAAA)) {
1392 } else if (type != qtype) {
1394 if (type != T_KEY && type != T_SIG)
1395 syslog(LOG_NOTICE|LOG_AUTH,
1396 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
1397 qname, p_class(C_IN), p_type(qtype),
1401 continue; /* XXX - had_error++ ? */
1406 if (strcasecmp(canonname, bp) != 0) {
1408 syslog(LOG_NOTICE|LOG_AUTH,
1409 AskedForGot, canonname, bp);
1412 continue; /* XXX - had_error++ ? */
1414 if (type == T_A && n != INADDRSZ) {
1418 if (type == T_AAAA && n != IN6ADDRSZ) {
1422 #ifdef FILTER_V4MAPPED
1423 if (type == T_AAAA) {
1424 struct in6_addr in6;
1425 memcpy(&in6, cp, sizeof(in6));
1426 if (IN6_IS_ADDR_V4MAPPED(&in6)) {
1436 nn = strlen(bp) + 1; /* for the \0 */
1440 /* don't overwrite pai */
1442 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
1443 afd = find_afd(ai.ai_family);
1448 cur->ai_next = get_ai(&ai, afd, (const char *)cp);
1449 if (cur->ai_next == NULL)
1451 while (cur && cur->ai_next)
1462 #if defined(RESOLVSORT)
1464 * We support only IPv4 address for backward
1465 * compatibility against gethostbyname(3).
1467 if (_res.nsort && qtype == T_A) {
1468 if (addr4sort(&sentinel) < 0) {
1469 freeaddrinfo(sentinel.ai_next);
1470 h_errno = NO_RECOVERY;
1474 #endif /*RESOLVSORT*/
1476 (void)get_canonname(pai, sentinel.ai_next, qname);
1478 (void)get_canonname(pai, sentinel.ai_next, canonname);
1479 h_errno = NETDB_SUCCESS;
1480 return sentinel.ai_next;
1483 h_errno = NO_RECOVERY;
1489 _dns_getaddrinfo(pai, hostname, res)
1490 const struct addrinfo *pai;
1491 const char *hostname;
1492 struct addrinfo **res;
1494 struct addrinfo *ai;
1495 querybuf *buf, *buf2;
1497 struct addrinfo sentinel, *cur;
1498 struct res_target q, q2;
1500 memset(&q, 0, sizeof(q2));
1501 memset(&q2, 0, sizeof(q2));
1502 memset(&sentinel, 0, sizeof(sentinel));
1505 buf = malloc(sizeof(*buf));
1507 h_errno = NETDB_INTERNAL;
1510 buf2 = malloc(sizeof(*buf2));
1513 h_errno = NETDB_INTERNAL;
1517 switch (pai->ai_family) {
1523 q.answer = buf->buf;
1524 q.anslen = sizeof(buf->buf);
1529 q2.answer = buf2->buf;
1530 q2.anslen = sizeof(buf2->buf);
1536 q.answer = buf->buf;
1537 q.anslen = sizeof(buf->buf);
1543 q.answer = buf->buf;
1544 q.anslen = sizeof(buf->buf);
1551 if (res_searchN(hostname, &q) < 0) {
1556 ai = getanswer(buf, q.n, q.name, q.qtype, pai);
1559 while (cur && cur->ai_next)
1563 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai);
1569 if (sentinel.ai_next == NULL)
1571 case HOST_NOT_FOUND:
1578 *res = sentinel.ai_next;
1582 static struct addrinfo *
1583 _gethtent(hostf, name, pai)
1586 const struct addrinfo *pai;
1589 char *cp, *tname, *cname;
1590 struct addrinfo hints, *res0, *res;
1593 char hostbuf[8*1024];
1596 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf)))
1600 if (!(cp = strpbrk(p, "#\n")))
1603 if (!(cp = strpbrk(p, " \t")))
1608 /* if this is not something we're looking for, skip it. */
1610 if (*cp == ' ' || *cp == '\t') {
1617 if ((cp = strpbrk(cp, " \t")) != NULL)
1619 if (strcasecmp(name, tname) == 0)
1625 /* we should not glob socktype/protocol here */
1626 memset(&hints, 0, sizeof(hints));
1627 hints.ai_family = pai->ai_family;
1628 hints.ai_socktype = SOCK_DGRAM;
1629 hints.ai_protocol = 0;
1630 hints.ai_flags = AI_NUMERICHOST;
1631 error = getaddrinfo(addr, "0", &hints, &res0);
1634 #ifdef FILTER_V4MAPPED
1635 /* XXX should check all items in the chain */
1636 if (res0->ai_family == AF_INET6 &&
1637 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) {
1642 for (res = res0; res; res = res->ai_next) {
1644 res->ai_flags = pai->ai_flags;
1645 res->ai_socktype = pai->ai_socktype;
1646 res->ai_protocol = pai->ai_protocol;
1648 if (pai->ai_flags & AI_CANONNAME) {
1649 if (get_canonname(pai, res, cname) != 0) {
1660 _files_getaddrinfo(pai, hostname, res)
1661 const struct addrinfo *pai;
1662 const char *hostname;
1663 struct addrinfo **res;
1666 struct addrinfo sentinel, *cur;
1669 sentinel.ai_next = NULL;
1672 if ((hostf = fopen(_PATH_HOSTS, "r")) == NULL)
1674 while ((p = _gethtent(hostf, hostname, pai)) != NULL) {
1676 while (cur && cur->ai_next)
1681 if (!sentinel.ai_next)
1684 *res = sentinel.ai_next;
1691 _nis_getaddrinfo(pai, hostname, res)
1692 const struct addrinfo *pai;
1693 const char *hostname;
1694 struct addrinfo **res;
1699 struct addrinfo sentinel, *cur;
1701 const struct afd *afd;
1704 sentinel.ai_next = NULL;
1707 af = (pai->ai_family == AF_UNSPEC) ? AF_INET : pai->ai_family;
1709 return (EAI_ADDRFAMILY);
1711 if ((hp = _gethostbynisname(hostname, af)) == NULL) {
1713 /* XXX: should be filled in */
1718 } else if (hp->h_name == NULL ||
1719 hp->h_name[0] == 0 || hp->h_addr_list[0] == NULL) {
1727 for (i = 0; hp->h_addr_list[i] != NULL; i++) {
1728 if (hp->h_addrtype != af)
1731 afd = find_afd(hp->h_addrtype);
1735 GET_AI(cur->ai_next, afd, hp->h_addr_list[i]);
1736 if ((pai->ai_flags & AI_CANONNAME) != 0) {
1738 * RFC2553 says that ai_canonname will be set only for
1739 * the first element. we do it for all the elements,
1740 * just for convenience.
1742 GET_CANONNAME(cur->ai_next, hp->h_name);
1745 while (cur && cur->ai_next)
1749 *res = sentinel.ai_next;
1753 if (sentinel.ai_next)
1754 freeaddrinfo(sentinel.ai_next);
1759 /* resolver logic */
1761 extern const char *__hostalias __P((const char *));
1765 * Formulate a normal query, send, and await answer.
1766 * Returned answer is placed in supplied buffer "answer".
1767 * Perform preliminary check of answer, returning success only
1768 * if no error is indicated and the answer count is nonzero.
1769 * Return the size of the response on success, -1 on error.
1770 * Error number is left in h_errno.
1772 * Caller must parse answer and determine whether it answers the question.
1775 res_queryN(name, target)
1776 const char *name; /* domain name */
1777 struct res_target *target;
1782 struct res_target *t;
1789 if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
1790 h_errno = NETDB_INTERNAL;
1794 buf = malloc(MAXPACKET);
1796 h_errno = NETDB_INTERNAL;
1800 for (t = target; t; t = t->next) {
1805 hp = (HEADER *)(void *)t->answer;
1806 hp->rcode = NOERROR; /* default */
1808 /* make it easier... */
1814 if (_res.options & RES_DEBUG)
1815 printf(";; res_query(%s, %d, %d)\n", name, class, type);
1818 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL,
1820 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0)
1821 n = res_opt(n, buf, MAXPACKET, anslen);
1824 if (_res.options & RES_DEBUG)
1825 printf(";; res_query: mkquery failed\n");
1828 h_errno = NO_RECOVERY;
1831 n = res_send(buf, n, answer, anslen);
1835 if (_res.options & RES_DEBUG)
1836 printf(";; res_query: send error\n");
1839 h_errno = TRY_AGAIN;
1844 if (n < 0 || n > anslen)
1845 hp->rcode = FORMERR; /* XXX not very informative */
1846 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
1847 rcode = hp->rcode; /* record most recent error */
1849 if (_res.options & RES_DEBUG)
1850 printf(";; rcode = %u, ancount=%u\n", hp->rcode,
1851 ntohs(hp->ancount));
1856 ancount += ntohs(hp->ancount);
1866 h_errno = HOST_NOT_FOUND;
1869 h_errno = TRY_AGAIN;
1878 h_errno = NO_RECOVERY;
1887 * Formulate a normal query, send, and retrieve answer in supplied buffer.
1888 * Return the size of the response on success, -1 on error.
1889 * If enabled, implement search rules until answer or unrecoverable failure
1890 * is detected. Error code, if any, is left in h_errno.
1893 res_searchN(name, target)
1894 const char *name; /* domain name */
1895 struct res_target *target;
1897 const char *cp, * const *domain;
1898 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/
1900 int trailing_dot, ret, saved_herrno;
1901 int got_nodata = 0, got_servfail = 0, tried_as_is = 0;
1903 if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
1904 h_errno = NETDB_INTERNAL;
1909 h_errno = HOST_NOT_FOUND; /* default, if we never query */
1911 for (cp = name; *cp; cp++)
1912 dots += (*cp == '.');
1914 if (cp > name && *--cp == '.')
1918 * if there aren't any dots, it could be a user-level alias
1920 if (!dots && (cp = __hostalias(name)) != NULL)
1921 return (res_queryN(cp, target));
1924 * If there are dots in the name already, let's just give it a try
1925 * 'as is'. The threshold can be set with the "ndots" option.
1928 if (dots >= _res.ndots) {
1929 ret = res_querydomainN(name, NULL, target);
1932 saved_herrno = h_errno;
1937 * We do at least one level of search if
1938 * - there is no dot and RES_DEFNAME is set, or
1939 * - there is at least one dot, there is no trailing dot,
1940 * and RES_DNSRCH is set.
1942 if ((!dots && (_res.options & RES_DEFNAMES)) ||
1943 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) {
1946 for (domain = (const char * const *)_res.dnsrch;
1950 ret = res_querydomainN(name, *domain, target);
1955 * If no server present, give up.
1956 * If name isn't found in this domain,
1957 * keep trying higher domains in the search list
1958 * (if that's enabled).
1959 * On a NO_DATA error, keep trying, otherwise
1960 * a wildcard entry of another type could keep us
1961 * from finding this entry higher in the domain.
1962 * If we get some other error (negative answer or
1963 * server failure), then stop searching up,
1964 * but try the input name below in case it's
1967 if (errno == ECONNREFUSED) {
1968 h_errno = TRY_AGAIN;
1976 case HOST_NOT_FOUND:
1980 if (hp->rcode == SERVFAIL) {
1981 /* try next search element, if any */
1987 /* anything else implies that we're done */
1991 * if we got here for some reason other than DNSRCH,
1992 * we only wanted one iteration of the loop, so stop.
1994 if (!(_res.options & RES_DNSRCH))
2000 * if we have not already tried the name "as is", do that now.
2001 * note that we do this regardless of how many dots were in the
2002 * name or whether it ends with a dot.
2004 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) {
2005 ret = res_querydomainN(name, NULL, target);
2011 * if we got here, we didn't satisfy the search.
2012 * if we did an initial full query, return that query's h_errno
2013 * (note that we wouldn't be here if that query had succeeded).
2014 * else if we ever got a nodata, send that back as the reason.
2015 * else send back meaningless h_errno, that being the one from
2016 * the last DNSRCH we did.
2018 if (saved_herrno != -1)
2019 h_errno = saved_herrno;
2020 else if (got_nodata)
2022 else if (got_servfail)
2023 h_errno = TRY_AGAIN;
2028 * Perform a call on res_query on the concatenation of name and domain,
2029 * removing a trailing dot from name if domain is NULL.
2032 res_querydomainN(name, domain, target)
2033 const char *name, *domain;
2034 struct res_target *target;
2036 char nbuf[MAXDNAME];
2037 const char *longname = nbuf;
2040 if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
2041 h_errno = NETDB_INTERNAL;
2045 if (_res.options & RES_DEBUG)
2046 printf(";; res_querydomain(%s, %s)\n",
2047 name, domain?domain:"<Nil>");
2049 if (domain == NULL) {
2051 * Check for trailing '.';
2052 * copy without '.' if present.
2055 if (n >= MAXDNAME) {
2056 h_errno = NO_RECOVERY;
2059 if (n > 0 && name[--n] == '.') {
2060 strncpy(nbuf, name, n);
2067 if (n + d + 1 >= MAXDNAME) {
2068 h_errno = NO_RECOVERY;
2071 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain);
2073 return (res_queryN(longname, target));