1 /* $FreeBSD: src/lib/libc/net/getaddrinfo.c,v 1.9.2.14 2002/11/08 17:49:31 ume Exp $ */
2 /* $DragonFly: src/lib/libc/net/getaddrinfo.c,v 1.3 2003/11/12 20:21:24 eirikn Exp $ */
3 /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */
6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the project nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator.
37 * Issues to be discussed:
38 * - Thread safe-ness must be checked.
39 * - Return values. There are nonstandard return values defined and used
40 * in the source code. This is because RFC2553 is silent about which error
41 * code must be returned for which situation.
42 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is
43 * invalid. current code - SEGV on freeaddrinfo(NULL)
46 * - The code filters out AFs that are not supported by the kernel,
47 * when globbing NULL hostname (to loopback, or wildcard). Is it the right
48 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG
50 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague.
51 * (1) what should we do against numeric hostname (2) what should we do
52 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready?
53 * non-loopback address configured? global address configured?
55 * OS specific notes for netbsd/openbsd/freebsd4/bsdi4:
56 * - To avoid search order issue, we have a big amount of code duplicate
57 * from gethnamaddr.c and some other places. The issues that there's no
58 * lower layer function to lookup "IPv4 or IPv6" record. Calling
59 * gethostbyname2 from getaddrinfo will end up in wrong search order, as
62 * OS specific notes for freebsd4:
63 * - FreeBSD supported $GAI. The code does not.
64 * - FreeBSD allowed classful IPv4 numeric (127.1), the code does not.
67 #include <sys/types.h>
68 #include <sys/param.h>
69 #include <sys/socket.h>
71 #include <netinet/in.h>
72 #include <arpa/inet.h>
73 #include <arpa/nameser.h>
84 #include "res_config.h"
90 #if defined(__KAME__) && defined(INET6)
99 static const char in_addrany[] = { 0, 0, 0, 0 };
100 static const char in_loopback[] = { 127, 0, 0, 1 };
102 static const char in6_addrany[] = {
103 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
105 static const char in6_loopback[] = {
106 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
110 static const struct afd {
115 const char *a_addrany;
116 const char *a_loopback;
121 {PF_INET6, sizeof(struct in6_addr),
122 sizeof(struct sockaddr_in6),
123 offsetof(struct sockaddr_in6, sin6_addr),
124 in6_addrany, in6_loopback, 1},
129 {PF_INET, sizeof(struct in_addr),
130 sizeof(struct sockaddr_in),
131 offsetof(struct sockaddr_in, sin_addr),
132 in_addrany, in_loopback, 0},
133 {0, 0, 0, 0, NULL, NULL, 0},
140 const char *e_protostr;
142 #define WILD_AF(ex) ((ex)->e_wild & 0x01)
143 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02)
144 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04)
147 static const struct explore explore[] = {
149 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 },
152 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
153 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
154 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
156 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
157 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
158 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
159 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
160 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
161 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 },
162 { -1, 0, 0, NULL, 0 },
171 #define MAXPACKET (64*1024)
175 u_char buf[MAXPACKET];
179 struct res_target *next;
180 const char *name; /* domain name */
181 int qclass, qtype; /* class and type of query */
182 u_char *answer; /* buffer to put answer */
183 int anslen; /* size of answer buffer */
184 int n; /* result length */
187 static int str_isnumber (const char *);
188 static int explore_fqdn (const struct addrinfo *, const char *,
189 const char *, struct addrinfo **);
190 static int explore_null (const struct addrinfo *,
191 const char *, struct addrinfo **);
192 static int explore_numeric (const struct addrinfo *, const char *,
193 const char *, struct addrinfo **);
194 static int explore_numeric_scope (const struct addrinfo *, const char *,
195 const char *, struct addrinfo **);
196 static int get_canonname (const struct addrinfo *,
197 struct addrinfo *, const char *);
198 static struct addrinfo *get_ai (const struct addrinfo *,
199 const struct afd *, const char *);
200 static int get_portmatch (const struct addrinfo *, const char *);
201 static int get_port (struct addrinfo *, const char *, int);
202 static const struct afd *find_afd (int);
203 static int addrconfig (struct addrinfo *);
205 static int ip6_str2scopeid (char *, struct sockaddr_in6 *, u_int32_t *);
208 static struct addrinfo *getanswer (const querybuf *, int, const char *,
209 int, const struct addrinfo *);
210 static int _dns_getaddrinfo (const struct addrinfo *, const char *,
212 static struct addrinfo *_gethtent (FILE *fp, const char *,
213 const struct addrinfo *);
214 static int _files_getaddrinfo (const struct addrinfo *, const char *,
217 static int _nis_getaddrinfo (const struct addrinfo *, const char *,
221 static int res_queryN (const char *, struct res_target *);
222 static int res_searchN (const char *, struct res_target *);
223 static int res_querydomainN (const char *, const char *,
224 struct res_target *);
226 static char *ai_errlist[] = {
228 "Address family for hostname not supported", /* EAI_ADDRFAMILY */
229 "Temporary failure in name resolution", /* EAI_AGAIN */
230 "Invalid value for ai_flags", /* EAI_BADFLAGS */
231 "Non-recoverable failure in name resolution", /* EAI_FAIL */
232 "ai_family not supported", /* EAI_FAMILY */
233 "Memory allocation failure", /* EAI_MEMORY */
234 "No address associated with hostname", /* EAI_NODATA */
235 "hostname nor servname provided, or not known", /* EAI_NONAME */
236 "servname not supported for ai_socktype", /* EAI_SERVICE */
237 "ai_socktype not supported", /* EAI_SOCKTYPE */
238 "System error returned in errno", /* EAI_SYSTEM */
239 "Invalid value for hints", /* EAI_BADHINTS */
240 "Resolved protocol is unknown", /* EAI_PROTOCOL */
241 "Unknown error", /* EAI_MAX */
245 * Select order host function.
247 #define MAXHOSTCONF 4
250 # define HOSTCONF "/etc/host.conf"
251 #endif /* !HOSTCONF */
254 int (*byname)(const struct addrinfo *, const char *,
259 static struct _hostconf _hostconf[MAXHOSTCONF] = {
267 static int _hostconf_init_done;
268 static void _hostconf_init(void);
270 /* Make getaddrinfo() thread-safe in libc for use with kernel threads. */
271 #include "libc_private.h"
272 #include "spinlock.h"
274 * XXX: Our res_*() is not thread-safe. So, we share lock between
275 * getaddrinfo() and getipnodeby*(). Still, we cannot use
276 * getaddrinfo() and getipnodeby*() in conjunction with other
277 * functions which call res_*().
279 spinlock_t __getaddrinfo_thread_lock = _SPINLOCK_INITIALIZER;
280 #define THREAD_LOCK() \
281 if (__isthreaded) _SPINLOCK(&__getaddrinfo_thread_lock);
282 #define THREAD_UNLOCK() \
283 if (__isthreaded) _SPINUNLOCK(&__getaddrinfo_thread_lock);
285 /* XXX macros that make external reference is BAD. */
287 #define GET_AI(ai, afd, addr) \
289 /* external reference: pai, error, and label free */ \
290 (ai) = get_ai(pai, (afd), (addr)); \
291 if ((ai) == NULL) { \
292 error = EAI_MEMORY; \
295 } while (/*CONSTCOND*/0)
297 #define GET_PORT(ai, serv) \
299 /* external reference: error and label free */ \
300 error = get_port((ai), (serv), 0); \
303 } while (/*CONSTCOND*/0)
305 #define GET_CANONNAME(ai, str) \
307 /* external reference: pai, error and label free */ \
308 error = get_canonname(pai, (ai), (str)); \
311 } while (/*CONSTCOND*/0)
315 /* external reference: error, and label bad */ \
319 } while (/*CONSTCOND*/0)
321 #define MATCH_FAMILY(x, y, w) \
322 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
323 #define MATCH(x, y, w) \
324 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
330 if (ecode < 0 || ecode > EAI_MAX)
332 return ai_errlist[ecode];
339 struct addrinfo *next;
343 if (ai->ai_canonname)
344 free(ai->ai_canonname);
345 /* no need to free(ai->ai_addr) */
361 (void)strtoul(p, &ep, 10);
362 if (errno == 0 && ep && *ep == '\0')
369 getaddrinfo(hostname, servname, hints, res)
370 const char *hostname, *servname;
371 const struct addrinfo *hints;
372 struct addrinfo **res;
374 struct addrinfo sentinel;
375 struct addrinfo *cur;
379 struct addrinfo *pai;
380 const struct explore *ex;
382 memset(&sentinel, 0, sizeof(sentinel));
386 pai->ai_family = PF_UNSPEC;
387 pai->ai_socktype = ANY;
388 pai->ai_protocol = ANY;
390 pai->ai_canonname = NULL;
394 if (hostname == NULL && servname == NULL)
397 /* error check for hints */
398 if (hints->ai_addrlen || hints->ai_canonname ||
399 hints->ai_addr || hints->ai_next)
400 ERR(EAI_BADHINTS); /* xxx */
401 if (hints->ai_flags & ~AI_MASK)
403 switch (hints->ai_family) {
413 memcpy(pai, hints, sizeof(*pai));
416 * if both socktype/protocol are specified, check if they
417 * are meaningful combination.
419 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
420 for (ex = explore; ex->e_af >= 0; ex++) {
421 if (pai->ai_family != ex->e_af)
423 if (ex->e_socktype == ANY)
425 if (ex->e_protocol == ANY)
427 if (pai->ai_socktype == ex->e_socktype &&
428 pai->ai_protocol != ex->e_protocol) {
436 * post-2553: AI_ALL and AI_V4MAPPED are effective only against
437 * AF_INET6 query. They need to be ignored if specified in other
440 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) {
442 case AI_ALL | AI_V4MAPPED:
443 if (pai->ai_family != AF_INET6)
444 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED);
451 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED);
457 * check for special cases. (1) numeric servname is disallowed if
458 * socktype/protocol are left unspecified. (2) servname is disallowed
459 * for raw and other inet{,6} sockets.
461 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
463 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
466 ai0 = *pai; /* backup *pai */
468 if (pai->ai_family == PF_UNSPEC) {
470 pai->ai_family = PF_INET6;
472 pai->ai_family = PF_INET;
475 error = get_portmatch(pai, servname);
484 /* NULL hostname, or numeric hostname */
485 for (ex = explore; ex->e_af >= 0; ex++) {
488 /* PF_UNSPEC entries are prepared for DNS queries only */
489 if (ex->e_af == PF_UNSPEC)
492 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
494 if (!MATCH(pai->ai_socktype, ex->e_socktype,
497 if (!MATCH(pai->ai_protocol, ex->e_protocol,
501 if (pai->ai_family == PF_UNSPEC)
502 pai->ai_family = ex->e_af;
503 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
504 pai->ai_socktype = ex->e_socktype;
505 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
506 pai->ai_protocol = ex->e_protocol;
508 if (hostname == NULL)
509 error = explore_null(pai, servname, &cur->ai_next);
511 error = explore_numeric_scope(pai, hostname, servname,
517 while (cur && cur->ai_next)
523 * If numreic representation of AF1 can be interpreted as FQDN
524 * representation of AF2, we need to think again about the code below.
526 if (sentinel.ai_next)
529 if (pai->ai_flags & AI_NUMERICHOST)
531 if (hostname == NULL)
534 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0))
538 * hostname as alphabetical name.
539 * we would like to prefer AF_INET6 than AF_INET, so we'll make a
542 for (ex = explore; ex->e_af >= 0; ex++) {
545 /* require exact match for family field */
546 if (pai->ai_family != ex->e_af)
549 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) {
552 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) {
556 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
557 pai->ai_socktype = ex->e_socktype;
558 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
559 pai->ai_protocol = ex->e_protocol;
561 error = explore_fqdn(pai, hostname, servname, &cur->ai_next);
563 while (cur && cur->ai_next)
568 if (sentinel.ai_next)
574 if (sentinel.ai_next) {
576 *res = sentinel.ai_next;
583 if (sentinel.ai_next)
584 freeaddrinfo(sentinel.ai_next);
594 static const char sep[] = "# \t\n";
597 for (p = *pp; (c = *p) != '\0'; p++) {
598 for (sp = sep; *sp != '\0'; sp++) {
603 p[1] = '\0'; /* ignore rest of line */
615 if (ret == NULL || *ret == '\0')
621 * Initialize hostconf structure.
632 _hostconf_init_done = 1;
635 if ((fp = fopen(p, "r")) == NULL)
637 while (n < MAXHOSTCONF && fgets(buf, sizeof(buf), fp)) {
639 if ((p = _hgetword(&line)) == NULL)
642 if (strcmp(p, "hosts") == 0
643 || strcmp(p, "local") == 0
644 || strcmp(p, "file") == 0
645 || strcmp(p, "files") == 0)
646 _hostconf[n++].byname = _files_getaddrinfo;
647 else if (strcmp(p, "dns") == 0
648 || strcmp(p, "bind") == 0)
649 _hostconf[n++].byname = _dns_getaddrinfo;
651 else if (strcmp(p, "nis") == 0)
652 _hostconf[n++].byname = _nis_getaddrinfo;
654 } while ((p = _hgetword(&line)) != NULL);
658 /* no keyword found. do not change default configuration */
661 for (; n < MAXHOSTCONF; n++)
662 _hostconf[n].byname = NULL;
666 * FQDN hostname, DNS lookup
669 explore_fqdn(pai, hostname, servname, res)
670 const struct addrinfo *pai;
671 const char *hostname;
672 const char *servname;
673 struct addrinfo **res;
675 struct addrinfo *result;
676 struct addrinfo *cur;
685 * if the servname does not match socktype/protocol, ignore it.
687 if (get_portmatch(pai, servname) != 0) {
692 if (!_hostconf_init_done)
695 for (i = 0; i < MAXHOSTCONF; i++) {
696 if (!_hostconf[i].byname)
698 error = (*_hostconf[i].byname)(pai, hostname, &result);
701 for (cur = result; cur; cur = cur->ai_next) {
702 GET_PORT(cur, servname);
703 /* canonname should be filled already */
713 freeaddrinfo(result);
719 * passive socket -> anyaddr (0.0.0.0 or ::)
720 * non-passive socket -> localhost (127.0.0.1 or ::1)
723 explore_null(pai, servname, res)
724 const struct addrinfo *pai;
725 const char *servname;
726 struct addrinfo **res;
729 const struct afd *afd;
730 struct addrinfo *cur;
731 struct addrinfo sentinel;
735 sentinel.ai_next = NULL;
739 * filter out AFs that are not supported by the kernel
742 s = socket(pai->ai_family, SOCK_DGRAM, 0);
750 * if the servname does not match socktype/protocol, ignore it.
752 if (get_portmatch(pai, servname) != 0)
755 afd = find_afd(pai->ai_family);
759 if (pai->ai_flags & AI_PASSIVE) {
760 GET_AI(cur->ai_next, afd, afd->a_addrany);
762 * GET_CANONNAME(cur->ai_next, "anyaddr");
764 GET_PORT(cur->ai_next, servname);
766 GET_AI(cur->ai_next, afd, afd->a_loopback);
768 * GET_CANONNAME(cur->ai_next, "localhost");
770 GET_PORT(cur->ai_next, servname);
774 *res = sentinel.ai_next;
778 if (sentinel.ai_next)
779 freeaddrinfo(sentinel.ai_next);
787 explore_numeric(pai, hostname, servname, res)
788 const struct addrinfo *pai;
789 const char *hostname;
790 const char *servname;
791 struct addrinfo **res;
793 const struct afd *afd;
794 struct addrinfo *cur;
795 struct addrinfo sentinel;
800 sentinel.ai_next = NULL;
804 * if the servname does not match socktype/protocol, ignore it.
806 if (get_portmatch(pai, servname) != 0)
809 afd = find_afd(pai->ai_family);
814 #if 1 /*X/Open spec*/
816 if (inet_aton(hostname, (struct in_addr *)pton) == 1) {
817 if (pai->ai_family == afd->a_af ||
818 pai->ai_family == PF_UNSPEC /*?*/) {
819 GET_AI(cur->ai_next, afd, pton);
820 GET_PORT(cur->ai_next, servname);
821 while (cur && cur->ai_next)
824 ERR(EAI_FAMILY); /*xxx*/
829 if (inet_pton(afd->a_af, hostname, pton) == 1) {
830 if (pai->ai_family == afd->a_af ||
831 pai->ai_family == PF_UNSPEC /*?*/) {
832 GET_AI(cur->ai_next, afd, pton);
833 GET_PORT(cur->ai_next, servname);
834 while (cur && cur->ai_next)
837 ERR(EAI_FAMILY); /* XXX */
842 *res = sentinel.ai_next;
847 if (sentinel.ai_next)
848 freeaddrinfo(sentinel.ai_next);
853 * numeric hostname with scope
856 explore_numeric_scope(pai, hostname, servname, res)
857 const struct addrinfo *pai;
858 const char *hostname;
859 const char *servname;
860 struct addrinfo **res;
862 #if !defined(SCOPE_DELIMITER) || !defined(INET6)
863 return explore_numeric(pai, hostname, servname, res);
865 const struct afd *afd;
866 struct addrinfo *cur;
868 char *cp, *hostname2 = NULL, *scope, *addr;
869 struct sockaddr_in6 *sin6;
872 * if the servname does not match socktype/protocol, ignore it.
874 if (get_portmatch(pai, servname) != 0)
877 afd = find_afd(pai->ai_family);
881 return explore_numeric(pai, hostname, servname, res);
883 cp = strchr(hostname, SCOPE_DELIMITER);
885 return explore_numeric(pai, hostname, servname, res);
888 * Handle special case of <scoped_address><delimiter><scope id>
890 hostname2 = strdup(hostname);
891 if (hostname2 == NULL)
893 /* terminate at the delimiter */
894 hostname2[cp - hostname] = '\0';
898 error = explore_numeric(pai, addr, servname, res);
902 for (cur = *res; cur; cur = cur->ai_next) {
903 if (cur->ai_family != AF_INET6)
905 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
906 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) {
908 return(EAI_NODATA); /* XXX: is return OK? */
910 sin6->sin6_scope_id = scopeid;
921 get_canonname(pai, ai, str)
922 const struct addrinfo *pai;
926 if ((pai->ai_flags & AI_CANONNAME) != 0) {
927 ai->ai_canonname = (char *)malloc(strlen(str) + 1);
928 if (ai->ai_canonname == NULL)
930 strlcpy(ai->ai_canonname, str, strlen(str) + 1);
935 static struct addrinfo *
936 get_ai(pai, afd, addr)
937 const struct addrinfo *pai;
938 const struct afd *afd;
944 struct in6_addr faith_prefix;
951 * Transfrom an IPv4 addr into a special IPv6 addr format for
952 * IPv6->IPv4 translation gateway. (only TCP is supported now)
954 * +-----------------------------------+------------+
955 * | faith prefix part (12 bytes) | embedded |
956 * | | IPv4 addr part (4 bytes)
957 * +-----------------------------------+------------+
959 * faith prefix part is specified as ascii IPv6 addr format
960 * in environmental variable GAI.
961 * For FAITH to work correctly, routing to faith prefix must be
962 * setup toward a machine where a FAITH daemon operates.
963 * Also, the machine must enable some mechanizm
964 * (e.g. faith interface hack) to divert those packet with
965 * faith prefixed destination addr to user-land FAITH daemon.
967 fp_str = getenv("GAI");
968 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 &&
969 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) {
973 memcpy(&v4a, addr, sizeof v4a);
974 v4a_top = v4a >> IN_CLASSA_NSHIFT;
975 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) &&
976 v4a_top != 0 && v4a != IN_LOOPBACKNET) {
977 afd = &afdl[N_INET6];
978 memcpy(&faith_prefix.s6_addr[12], addr,
979 sizeof(struct in_addr));
985 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo)
990 memcpy(ai, pai, sizeof(struct addrinfo));
991 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
992 memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
993 ai->ai_addr->sa_len = afd->a_socklen;
994 ai->ai_addrlen = afd->a_socklen;
995 ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
996 p = (char *)(ai->ai_addr);
999 memcpy(p + afd->a_off, &faith_prefix, afd->a_addrlen);
1002 memcpy(p + afd->a_off, addr, afd->a_addrlen);
1008 get_portmatch(ai, servname)
1009 const struct addrinfo *ai;
1010 const char *servname;
1013 /* get_port does not touch first argument. when matchonly == 1. */
1014 /* LINTED const cast */
1015 return get_port((struct addrinfo *)ai, servname, 1);
1019 get_port(ai, servname, matchonly)
1020 struct addrinfo *ai;
1021 const char *servname;
1029 if (servname == NULL)
1031 switch (ai->ai_family) {
1041 switch (ai->ai_socktype) {
1052 return EAI_SOCKTYPE;
1055 if (str_isnumber(servname)) {
1058 port = atoi(servname);
1059 if (port < 0 || port > 65535)
1063 switch (ai->ai_socktype) {
1075 if ((sp = getservbyname(servname, proto)) == NULL)
1081 switch (ai->ai_family) {
1083 ((struct sockaddr_in *)(void *)
1084 ai->ai_addr)->sin_port = port;
1088 ((struct sockaddr_in6 *)(void *)
1089 ai->ai_addr)->sin6_port = port;
1098 static const struct afd *
1102 const struct afd *afd;
1104 if (af == PF_UNSPEC)
1106 for (afd = afdl; afd->a_af; afd++) {
1107 if (afd->a_af == af)
1114 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend
1115 * will take care of it.
1116 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure
1117 * if the code is right or not.
1119 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with
1124 struct addrinfo *pai;
1130 * Note that implementation dependent test for address
1131 * configuration should be done everytime called
1132 * (or apropriate interval),
1133 * because addresses will be dynamically assigned or deleted.
1135 af = pai->ai_family;
1136 if (af == AF_UNSPEC) {
1137 if ((s = socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
1141 if ((s = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
1148 if (af != AF_UNSPEC) {
1149 if ((s = socket(af, SOCK_DGRAM, 0)) < 0)
1153 pai->ai_family = af;
1158 /* convert a string to a scope identifier. XXX: IPv6 specific */
1160 ip6_str2scopeid(scope, sin6, scopeid)
1162 struct sockaddr_in6 *sin6;
1166 struct in6_addr *a6;
1169 a6 = &sin6->sin6_addr;
1171 /* empty scopeid portion is invalid */
1175 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) {
1177 * We currently assume a one-to-one mapping between links
1178 * and interfaces, so we simply use interface indices for
1179 * like-local scopes.
1181 *scopeid = if_nametoindex(scope);
1187 /* still unclear about literal, allow numeric only - placeholder */
1188 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
1190 if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
1193 goto trynumeric; /* global */
1195 /* try to convert to a numeric id as a last resort */
1198 lscopeid = strtoul(scope, &ep, 10);
1199 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL);
1200 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid)
1209 struct addrinfo *ai;
1214 addr4sort(struct addrinfo *sentinel)
1216 struct addrinfo *ai;
1217 struct addr_ptr *addrs, addr;
1218 struct sockaddr_in *sin;
1225 for (ai = sentinel->ai_next; ai; ai = ai->ai_next)
1228 return 0; /* We don't need sorting. */
1229 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL)
1232 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) {
1233 sin = (struct sockaddr_in *)ai->ai_addr;
1234 for (j = 0; (unsigned)j < _res.nsort; j++) {
1235 if (_res.sort_list[j].addr.s_addr ==
1236 (sin->sin_addr.s_addr & _res.sort_list[j].mask))
1241 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval)
1250 while (needsort < naddrs) {
1251 for (j = needsort - 1; j >= 0; j--) {
1252 if (addrs[j].aval > addrs[j+1].aval) {
1254 addrs[j] = addrs[j + 1];
1255 addrs[j + 1] = addr;
1263 for (i = 0; i < naddrs; ++i) {
1264 ai->ai_next = addrs[i].ai;
1271 #endif /*RESOLVSORT*/
1274 static const char AskedForGot[] =
1275 "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
1278 static struct addrinfo *
1279 getanswer(answer, anslen, qname, qtype, pai)
1280 const querybuf *answer;
1284 const struct addrinfo *pai;
1286 struct addrinfo sentinel, *cur;
1288 const struct afd *afd;
1295 int type, class, ancount, qdcount;
1296 int haveanswer, had_error;
1297 char tbuf[MAXDNAME];
1298 int (*name_ok) (const char *);
1299 char hostbuf[8*1024];
1301 memset(&sentinel, 0, sizeof(sentinel));
1305 eom = answer->buf + anslen;
1309 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/
1313 return (NULL); /* XXX should be abort(); */
1316 * find first satisfactory answer
1319 ancount = ntohs(hp->ancount);
1320 qdcount = ntohs(hp->qdcount);
1322 ep = hostbuf + sizeof hostbuf;
1323 cp = answer->buf + HFIXEDSZ;
1325 h_errno = NO_RECOVERY;
1328 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1329 if ((n < 0) || !(*name_ok)(bp)) {
1330 h_errno = NO_RECOVERY;
1334 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
1335 /* res_send() has already verified that the query name is the
1336 * same as the one we sent; this just gets the expanded name
1337 * (i.e., with the succeeding search-domain tacked on).
1339 n = strlen(bp) + 1; /* for the \0 */
1340 if (n >= MAXHOSTNAMELEN) {
1341 h_errno = NO_RECOVERY;
1346 /* The qname can be abbreviated, but h_name is now absolute. */
1351 while (ancount-- > 0 && cp < eom && !had_error) {
1352 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1353 if ((n < 0) || !(*name_ok)(bp)) {
1358 type = _getshort(cp);
1359 cp += INT16SZ; /* type */
1360 class = _getshort(cp);
1361 cp += INT16SZ + INT32SZ; /* class, TTL */
1363 cp += INT16SZ; /* len */
1364 if (class != C_IN) {
1365 /* XXX - debug? syslog? */
1367 continue; /* XXX - had_error++ ? */
1369 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
1371 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
1372 if ((n < 0) || !(*name_ok)(tbuf)) {
1377 /* Get canonical name. */
1378 n = strlen(tbuf) + 1; /* for the \0 */
1379 if (n > ep - bp || n >= MAXHOSTNAMELEN) {
1383 strlcpy(bp, tbuf, ep - bp);
1388 if (qtype == T_ANY) {
1389 if (!(type == T_A || type == T_AAAA)) {
1393 } else if (type != qtype) {
1395 if (type != T_KEY && type != T_SIG)
1396 syslog(LOG_NOTICE|LOG_AUTH,
1397 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
1398 qname, p_class(C_IN), p_type(qtype),
1402 continue; /* XXX - had_error++ ? */
1407 if (strcasecmp(canonname, bp) != 0) {
1409 syslog(LOG_NOTICE|LOG_AUTH,
1410 AskedForGot, canonname, bp);
1413 continue; /* XXX - had_error++ ? */
1415 if (type == T_A && n != INADDRSZ) {
1419 if (type == T_AAAA && n != IN6ADDRSZ) {
1423 #ifdef FILTER_V4MAPPED
1424 if (type == T_AAAA) {
1425 struct in6_addr in6;
1426 memcpy(&in6, cp, sizeof(in6));
1427 if (IN6_IS_ADDR_V4MAPPED(&in6)) {
1437 nn = strlen(bp) + 1; /* for the \0 */
1441 /* don't overwrite pai */
1443 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
1444 afd = find_afd(ai.ai_family);
1449 cur->ai_next = get_ai(&ai, afd, (const char *)cp);
1450 if (cur->ai_next == NULL)
1452 while (cur && cur->ai_next)
1463 #if defined(RESOLVSORT)
1465 * We support only IPv4 address for backward
1466 * compatibility against gethostbyname(3).
1468 if (_res.nsort && qtype == T_A) {
1469 if (addr4sort(&sentinel) < 0) {
1470 freeaddrinfo(sentinel.ai_next);
1471 h_errno = NO_RECOVERY;
1475 #endif /*RESOLVSORT*/
1477 (void)get_canonname(pai, sentinel.ai_next, qname);
1479 (void)get_canonname(pai, sentinel.ai_next, canonname);
1480 h_errno = NETDB_SUCCESS;
1481 return sentinel.ai_next;
1484 h_errno = NO_RECOVERY;
1490 _dns_getaddrinfo(pai, hostname, res)
1491 const struct addrinfo *pai;
1492 const char *hostname;
1493 struct addrinfo **res;
1495 struct addrinfo *ai;
1496 querybuf *buf, *buf2;
1498 struct addrinfo sentinel, *cur;
1499 struct res_target q, q2;
1501 memset(&q, 0, sizeof(q2));
1502 memset(&q2, 0, sizeof(q2));
1503 memset(&sentinel, 0, sizeof(sentinel));
1506 buf = malloc(sizeof(*buf));
1508 h_errno = NETDB_INTERNAL;
1511 buf2 = malloc(sizeof(*buf2));
1514 h_errno = NETDB_INTERNAL;
1518 switch (pai->ai_family) {
1524 q.answer = buf->buf;
1525 q.anslen = sizeof(buf->buf);
1530 q2.answer = buf2->buf;
1531 q2.anslen = sizeof(buf2->buf);
1537 q.answer = buf->buf;
1538 q.anslen = sizeof(buf->buf);
1544 q.answer = buf->buf;
1545 q.anslen = sizeof(buf->buf);
1552 if (res_searchN(hostname, &q) < 0) {
1557 ai = getanswer(buf, q.n, q.name, q.qtype, pai);
1560 while (cur && cur->ai_next)
1564 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai);
1570 if (sentinel.ai_next == NULL)
1572 case HOST_NOT_FOUND:
1579 *res = sentinel.ai_next;
1583 static struct addrinfo *
1584 _gethtent(hostf, name, pai)
1587 const struct addrinfo *pai;
1590 char *cp, *tname, *cname;
1591 struct addrinfo hints, *res0, *res;
1594 char hostbuf[8*1024];
1597 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf)))
1601 if (!(cp = strpbrk(p, "#\n")))
1604 if (!(cp = strpbrk(p, " \t")))
1609 /* if this is not something we're looking for, skip it. */
1611 if (*cp == ' ' || *cp == '\t') {
1618 if ((cp = strpbrk(cp, " \t")) != NULL)
1620 if (strcasecmp(name, tname) == 0)
1626 /* we should not glob socktype/protocol here */
1627 memset(&hints, 0, sizeof(hints));
1628 hints.ai_family = pai->ai_family;
1629 hints.ai_socktype = SOCK_DGRAM;
1630 hints.ai_protocol = 0;
1631 hints.ai_flags = AI_NUMERICHOST;
1632 error = getaddrinfo(addr, "0", &hints, &res0);
1635 #ifdef FILTER_V4MAPPED
1636 /* XXX should check all items in the chain */
1637 if (res0->ai_family == AF_INET6 &&
1638 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) {
1643 for (res = res0; res; res = res->ai_next) {
1645 res->ai_flags = pai->ai_flags;
1646 res->ai_socktype = pai->ai_socktype;
1647 res->ai_protocol = pai->ai_protocol;
1649 if (pai->ai_flags & AI_CANONNAME) {
1650 if (get_canonname(pai, res, cname) != 0) {
1661 _files_getaddrinfo(pai, hostname, res)
1662 const struct addrinfo *pai;
1663 const char *hostname;
1664 struct addrinfo **res;
1667 struct addrinfo sentinel, *cur;
1670 sentinel.ai_next = NULL;
1673 if ((hostf = fopen(_PATH_HOSTS, "r")) == NULL)
1675 while ((p = _gethtent(hostf, hostname, pai)) != NULL) {
1677 while (cur && cur->ai_next)
1682 if (!sentinel.ai_next)
1685 *res = sentinel.ai_next;
1692 _nis_getaddrinfo(pai, hostname, res)
1693 const struct addrinfo *pai;
1694 const char *hostname;
1695 struct addrinfo **res;
1700 struct addrinfo sentinel, *cur;
1702 const struct afd *afd;
1705 sentinel.ai_next = NULL;
1708 af = (pai->ai_family == AF_UNSPEC) ? AF_INET : pai->ai_family;
1710 return (EAI_ADDRFAMILY);
1712 if ((hp = _gethostbynisname(hostname, af)) == NULL) {
1714 /* XXX: should be filled in */
1719 } else if (hp->h_name == NULL ||
1720 hp->h_name[0] == 0 || hp->h_addr_list[0] == NULL) {
1728 for (i = 0; hp->h_addr_list[i] != NULL; i++) {
1729 if (hp->h_addrtype != af)
1732 afd = find_afd(hp->h_addrtype);
1736 GET_AI(cur->ai_next, afd, hp->h_addr_list[i]);
1737 if ((pai->ai_flags & AI_CANONNAME) != 0) {
1739 * RFC2553 says that ai_canonname will be set only for
1740 * the first element. we do it for all the elements,
1741 * just for convenience.
1743 GET_CANONNAME(cur->ai_next, hp->h_name);
1746 while (cur && cur->ai_next)
1750 *res = sentinel.ai_next;
1754 if (sentinel.ai_next)
1755 freeaddrinfo(sentinel.ai_next);
1760 /* resolver logic */
1762 extern const char *__hostalias (const char *);
1766 * Formulate a normal query, send, and await answer.
1767 * Returned answer is placed in supplied buffer "answer".
1768 * Perform preliminary check of answer, returning success only
1769 * if no error is indicated and the answer count is nonzero.
1770 * Return the size of the response on success, -1 on error.
1771 * Error number is left in h_errno.
1773 * Caller must parse answer and determine whether it answers the question.
1776 res_queryN(name, target)
1777 const char *name; /* domain name */
1778 struct res_target *target;
1783 struct res_target *t;
1790 if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
1791 h_errno = NETDB_INTERNAL;
1795 buf = malloc(MAXPACKET);
1797 h_errno = NETDB_INTERNAL;
1801 for (t = target; t; t = t->next) {
1806 hp = (HEADER *)(void *)t->answer;
1807 hp->rcode = NOERROR; /* default */
1809 /* make it easier... */
1815 if (_res.options & RES_DEBUG)
1816 printf(";; res_query(%s, %d, %d)\n", name, class, type);
1819 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL,
1821 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0)
1822 n = res_opt(n, buf, MAXPACKET, anslen);
1825 if (_res.options & RES_DEBUG)
1826 printf(";; res_query: mkquery failed\n");
1829 h_errno = NO_RECOVERY;
1832 n = res_send(buf, n, answer, anslen);
1836 if (_res.options & RES_DEBUG)
1837 printf(";; res_query: send error\n");
1840 h_errno = TRY_AGAIN;
1845 if (n < 0 || n > anslen)
1846 hp->rcode = FORMERR; /* XXX not very informative */
1847 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
1848 rcode = hp->rcode; /* record most recent error */
1850 if (_res.options & RES_DEBUG)
1851 printf(";; rcode = %u, ancount=%u\n", hp->rcode,
1852 ntohs(hp->ancount));
1857 ancount += ntohs(hp->ancount);
1867 h_errno = HOST_NOT_FOUND;
1870 h_errno = TRY_AGAIN;
1879 h_errno = NO_RECOVERY;
1888 * Formulate a normal query, send, and retrieve answer in supplied buffer.
1889 * Return the size of the response on success, -1 on error.
1890 * If enabled, implement search rules until answer or unrecoverable failure
1891 * is detected. Error code, if any, is left in h_errno.
1894 res_searchN(name, target)
1895 const char *name; /* domain name */
1896 struct res_target *target;
1898 const char *cp, * const *domain;
1899 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/
1901 int trailing_dot, ret, saved_herrno;
1902 int got_nodata = 0, got_servfail = 0, tried_as_is = 0;
1904 if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
1905 h_errno = NETDB_INTERNAL;
1910 h_errno = HOST_NOT_FOUND; /* default, if we never query */
1912 for (cp = name; *cp; cp++)
1913 dots += (*cp == '.');
1915 if (cp > name && *--cp == '.')
1919 * if there aren't any dots, it could be a user-level alias
1921 if (!dots && (cp = __hostalias(name)) != NULL)
1922 return (res_queryN(cp, target));
1925 * If there are dots in the name already, let's just give it a try
1926 * 'as is'. The threshold can be set with the "ndots" option.
1929 if (dots >= _res.ndots) {
1930 ret = res_querydomainN(name, NULL, target);
1933 saved_herrno = h_errno;
1938 * We do at least one level of search if
1939 * - there is no dot and RES_DEFNAME is set, or
1940 * - there is at least one dot, there is no trailing dot,
1941 * and RES_DNSRCH is set.
1943 if ((!dots && (_res.options & RES_DEFNAMES)) ||
1944 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) {
1947 for (domain = (const char * const *)_res.dnsrch;
1951 ret = res_querydomainN(name, *domain, target);
1956 * If no server present, give up.
1957 * If name isn't found in this domain,
1958 * keep trying higher domains in the search list
1959 * (if that's enabled).
1960 * On a NO_DATA error, keep trying, otherwise
1961 * a wildcard entry of another type could keep us
1962 * from finding this entry higher in the domain.
1963 * If we get some other error (negative answer or
1964 * server failure), then stop searching up,
1965 * but try the input name below in case it's
1968 if (errno == ECONNREFUSED) {
1969 h_errno = TRY_AGAIN;
1977 case HOST_NOT_FOUND:
1981 if (hp->rcode == SERVFAIL) {
1982 /* try next search element, if any */
1988 /* anything else implies that we're done */
1992 * if we got here for some reason other than DNSRCH,
1993 * we only wanted one iteration of the loop, so stop.
1995 if (!(_res.options & RES_DNSRCH))
2001 * if we have not already tried the name "as is", do that now.
2002 * note that we do this regardless of how many dots were in the
2003 * name or whether it ends with a dot.
2005 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) {
2006 ret = res_querydomainN(name, NULL, target);
2012 * if we got here, we didn't satisfy the search.
2013 * if we did an initial full query, return that query's h_errno
2014 * (note that we wouldn't be here if that query had succeeded).
2015 * else if we ever got a nodata, send that back as the reason.
2016 * else send back meaningless h_errno, that being the one from
2017 * the last DNSRCH we did.
2019 if (saved_herrno != -1)
2020 h_errno = saved_herrno;
2021 else if (got_nodata)
2023 else if (got_servfail)
2024 h_errno = TRY_AGAIN;
2029 * Perform a call on res_query on the concatenation of name and domain,
2030 * removing a trailing dot from name if domain is NULL.
2033 res_querydomainN(name, domain, target)
2034 const char *name, *domain;
2035 struct res_target *target;
2037 char nbuf[MAXDNAME];
2038 const char *longname = nbuf;
2041 if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
2042 h_errno = NETDB_INTERNAL;
2046 if (_res.options & RES_DEBUG)
2047 printf(";; res_querydomain(%s, %s)\n",
2048 name, domain?domain:"<Nil>");
2050 if (domain == NULL) {
2052 * Check for trailing '.';
2053 * copy without '.' if present.
2056 if (n >= MAXDNAME) {
2057 h_errno = NO_RECOVERY;
2060 if (n > 0 && name[--n] == '.') {
2061 strncpy(nbuf, name, n);
2068 if (n + d + 1 >= MAXDNAME) {
2069 h_errno = NO_RECOVERY;
2072 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain);
2074 return (res_queryN(longname, target));