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 1.6 2005/11/13 02:04:47 swildner 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 "namespace.h"
68 #include <sys/types.h>
69 #include <sys/param.h>
70 #include <sys/socket.h>
72 #include <netinet/in.h>
73 #include <arpa/inet.h>
74 #include <arpa/nameser.h>
84 #include "un-namespace.h"
86 #include "res_config.h"
92 #if defined(__KAME__) && defined(INET6)
101 static const char in_addrany[] = { 0, 0, 0, 0 };
102 static const char in_loopback[] = { 127, 0, 0, 1 };
104 static const char in6_addrany[] = {
105 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
107 static const char in6_loopback[] = {
108 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
112 static const struct afd {
117 const char *a_addrany;
118 const char *a_loopback;
123 {PF_INET6, sizeof(struct in6_addr),
124 sizeof(struct sockaddr_in6),
125 offsetof(struct sockaddr_in6, sin6_addr),
126 in6_addrany, in6_loopback, 1},
131 {PF_INET, sizeof(struct in_addr),
132 sizeof(struct sockaddr_in),
133 offsetof(struct sockaddr_in, sin_addr),
134 in_addrany, in_loopback, 0},
135 {0, 0, 0, 0, NULL, NULL, 0},
142 const char *e_protostr;
144 #define WILD_AF(ex) ((ex)->e_wild & 0x01)
145 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02)
146 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04)
149 static const struct explore explore[] = {
151 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 },
154 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
155 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
156 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
158 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
159 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
160 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
161 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
162 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
163 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 },
164 { -1, 0, 0, NULL, 0 },
173 #define MAXPACKET (64*1024)
177 u_char buf[MAXPACKET];
181 struct res_target *next;
182 const char *name; /* domain name */
183 int qclass, qtype; /* class and type of query */
184 u_char *answer; /* buffer to put answer */
185 int anslen; /* size of answer buffer */
186 int n; /* result length */
189 static int str_isnumber (const char *);
190 static int explore_fqdn (const struct addrinfo *, const char *,
191 const char *, struct addrinfo **);
192 static int explore_null (const struct addrinfo *,
193 const char *, struct addrinfo **);
194 static int explore_numeric (const struct addrinfo *, const char *,
195 const char *, struct addrinfo **);
196 static int explore_numeric_scope (const struct addrinfo *, const char *,
197 const char *, struct addrinfo **);
198 static int get_canonname (const struct addrinfo *,
199 struct addrinfo *, const char *);
200 static struct addrinfo *get_ai (const struct addrinfo *,
201 const struct afd *, const char *);
202 static int get_portmatch (const struct addrinfo *, const char *);
203 static int get_port (struct addrinfo *, const char *, int);
204 static const struct afd *find_afd (int);
205 static int addrconfig (struct addrinfo *);
207 static int ip6_str2scopeid (char *, struct sockaddr_in6 *, u_int32_t *);
210 static struct addrinfo *getanswer (const querybuf *, int, const char *,
211 int, const struct addrinfo *);
212 static int _dns_getaddrinfo (const struct addrinfo *, const char *,
214 static struct addrinfo *_gethtent (FILE *fp, const char *,
215 const struct addrinfo *);
216 static int _files_getaddrinfo (const struct addrinfo *, const char *,
219 static int _nis_getaddrinfo (const struct addrinfo *, const char *,
223 static int res_queryN (const char *, struct res_target *);
224 static int res_searchN (const char *, struct res_target *);
225 static int res_querydomainN (const char *, const char *,
226 struct res_target *);
228 static char *ai_errlist[] = {
230 "Address family for hostname not supported", /* EAI_ADDRFAMILY */
231 "Temporary failure in name resolution", /* EAI_AGAIN */
232 "Invalid value for ai_flags", /* EAI_BADFLAGS */
233 "Non-recoverable failure in name resolution", /* EAI_FAIL */
234 "ai_family not supported", /* EAI_FAMILY */
235 "Memory allocation failure", /* EAI_MEMORY */
236 "No address associated with hostname", /* EAI_NODATA */
237 "hostname nor servname provided, or not known", /* EAI_NONAME */
238 "servname not supported for ai_socktype", /* EAI_SERVICE */
239 "ai_socktype not supported", /* EAI_SOCKTYPE */
240 "System error returned in errno", /* EAI_SYSTEM */
241 "Invalid value for hints", /* EAI_BADHINTS */
242 "Resolved protocol is unknown", /* EAI_PROTOCOL */
243 "Unknown error", /* EAI_MAX */
247 * Select order host function.
249 #define MAXHOSTCONF 4
252 # define HOSTCONF "/etc/host.conf"
253 #endif /* !HOSTCONF */
256 int (*byname)(const struct addrinfo *, const char *,
261 static struct _hostconf _hostconf[MAXHOSTCONF] = {
269 static int _hostconf_init_done;
270 static void _hostconf_init(void);
272 /* Make getaddrinfo() thread-safe in libc for use with kernel threads. */
273 #include "libc_private.h"
274 #include "spinlock.h"
276 * XXX: Our res_*() is not thread-safe. So, we share lock between
277 * getaddrinfo() and getipnodeby*(). Still, we cannot use
278 * getaddrinfo() and getipnodeby*() in conjunction with other
279 * functions which call res_*().
281 spinlock_t __getaddrinfo_thread_lock = _SPINLOCK_INITIALIZER;
282 #define THREAD_LOCK() \
283 if (__isthreaded) _SPINLOCK(&__getaddrinfo_thread_lock);
284 #define THREAD_UNLOCK() \
285 if (__isthreaded) _SPINUNLOCK(&__getaddrinfo_thread_lock);
287 /* XXX macros that make external reference is BAD. */
289 #define GET_AI(ai, afd, addr) \
291 /* external reference: pai, error, and label free */ \
292 (ai) = get_ai(pai, (afd), (addr)); \
293 if ((ai) == NULL) { \
294 error = EAI_MEMORY; \
297 } while (/*CONSTCOND*/0)
299 #define GET_PORT(ai, serv) \
301 /* external reference: error and label free */ \
302 error = get_port((ai), (serv), 0); \
305 } while (/*CONSTCOND*/0)
307 #define GET_CANONNAME(ai, str) \
309 /* external reference: pai, error and label free */ \
310 error = get_canonname(pai, (ai), (str)); \
313 } while (/*CONSTCOND*/0)
317 /* external reference: error, and label bad */ \
321 } while (/*CONSTCOND*/0)
323 #define MATCH_FAMILY(x, y, w) \
324 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
325 #define MATCH(x, y, w) \
326 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
329 gai_strerror(int ecode)
331 if (ecode < 0 || ecode > EAI_MAX)
333 return ai_errlist[ecode];
337 freeaddrinfo(struct addrinfo *ai)
339 struct addrinfo *next;
343 if (ai->ai_canonname)
344 free(ai->ai_canonname);
345 /* no need to free(ai->ai_addr) */
352 str_isnumber(const char *p)
361 if (errno == 0 && ep && *ep == '\0')
368 getaddrinfo(const char *hostname, const char *servname,
369 const struct addrinfo *hints, struct addrinfo **res)
371 struct addrinfo sentinel;
372 struct addrinfo *cur;
376 struct addrinfo *pai;
377 const struct explore *ex;
379 memset(&sentinel, 0, sizeof(sentinel));
383 pai->ai_family = PF_UNSPEC;
384 pai->ai_socktype = ANY;
385 pai->ai_protocol = ANY;
387 pai->ai_canonname = NULL;
391 if (hostname == NULL && servname == NULL)
394 /* error check for hints */
395 if (hints->ai_addrlen || hints->ai_canonname ||
396 hints->ai_addr || hints->ai_next)
397 ERR(EAI_BADHINTS); /* xxx */
398 if (hints->ai_flags & ~AI_MASK)
400 switch (hints->ai_family) {
410 memcpy(pai, hints, sizeof(*pai));
413 * if both socktype/protocol are specified, check if they
414 * are meaningful combination.
416 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
417 for (ex = explore; ex->e_af >= 0; ex++) {
418 if (pai->ai_family != ex->e_af)
420 if (ex->e_socktype == ANY)
422 if (ex->e_protocol == ANY)
424 if (pai->ai_socktype == ex->e_socktype &&
425 pai->ai_protocol != ex->e_protocol) {
433 * post-2553: AI_ALL and AI_V4MAPPED are effective only against
434 * AF_INET6 query. They need to be ignored if specified in other
437 switch (pai->ai_flags & (AI_ALL | AI_V4MAPPED)) {
439 case AI_ALL | AI_V4MAPPED:
440 if (pai->ai_family != AF_INET6)
441 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED);
448 pai->ai_flags &= ~(AI_ALL | AI_V4MAPPED);
454 * check for special cases. (1) numeric servname is disallowed if
455 * socktype/protocol are left unspecified. (2) servname is disallowed
456 * for raw and other inet{,6} sockets.
458 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
460 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
463 ai0 = *pai; /* backup *pai */
465 if (pai->ai_family == PF_UNSPEC) {
467 pai->ai_family = PF_INET6;
469 pai->ai_family = PF_INET;
472 error = get_portmatch(pai, servname);
481 /* NULL hostname, or numeric hostname */
482 for (ex = explore; ex->e_af >= 0; ex++) {
485 /* PF_UNSPEC entries are prepared for DNS queries only */
486 if (ex->e_af == PF_UNSPEC)
489 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
491 if (!MATCH(pai->ai_socktype, ex->e_socktype,
494 if (!MATCH(pai->ai_protocol, ex->e_protocol,
498 if (pai->ai_family == PF_UNSPEC)
499 pai->ai_family = ex->e_af;
500 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
501 pai->ai_socktype = ex->e_socktype;
502 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
503 pai->ai_protocol = ex->e_protocol;
505 if (hostname == NULL)
506 error = explore_null(pai, servname, &cur->ai_next);
508 error = explore_numeric_scope(pai, hostname, servname,
514 while (cur && cur->ai_next)
520 * If numreic representation of AF1 can be interpreted as FQDN
521 * representation of AF2, we need to think again about the code below.
523 if (sentinel.ai_next)
526 if (pai->ai_flags & AI_NUMERICHOST)
528 if (hostname == NULL)
531 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0))
535 * hostname as alphabetical name.
536 * we would like to prefer AF_INET6 than AF_INET, so we'll make a
539 for (ex = explore; ex->e_af >= 0; ex++) {
542 /* require exact match for family field */
543 if (pai->ai_family != ex->e_af)
546 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex))) {
549 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex))) {
553 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
554 pai->ai_socktype = ex->e_socktype;
555 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
556 pai->ai_protocol = ex->e_protocol;
558 error = explore_fqdn(pai, hostname, servname, &cur->ai_next);
560 while (cur && cur->ai_next)
565 if (sentinel.ai_next)
571 if (sentinel.ai_next) {
573 *res = sentinel.ai_next;
580 if (sentinel.ai_next)
581 freeaddrinfo(sentinel.ai_next);
591 static const char sep[] = "# \t\n";
594 for (p = *pp; (c = *p) != '\0'; p++) {
595 for (sp = sep; *sp != '\0'; sp++) {
600 p[1] = '\0'; /* ignore rest of line */
612 if (ret == NULL || *ret == '\0')
618 * Initialize hostconf structure.
629 _hostconf_init_done = 1;
632 if ((fp = fopen(p, "r")) == NULL)
634 while (n < MAXHOSTCONF && fgets(buf, sizeof(buf), fp)) {
636 if ((p = _hgetword(&line)) == NULL)
639 if (strcmp(p, "hosts") == 0
640 || strcmp(p, "local") == 0
641 || strcmp(p, "file") == 0
642 || strcmp(p, "files") == 0)
643 _hostconf[n++].byname = _files_getaddrinfo;
644 else if (strcmp(p, "dns") == 0
645 || strcmp(p, "bind") == 0)
646 _hostconf[n++].byname = _dns_getaddrinfo;
648 else if (strcmp(p, "nis") == 0)
649 _hostconf[n++].byname = _nis_getaddrinfo;
651 } while ((p = _hgetword(&line)) != NULL);
655 /* no keyword found. do not change default configuration */
658 for (; n < MAXHOSTCONF; n++)
659 _hostconf[n].byname = NULL;
663 * FQDN hostname, DNS lookup
666 explore_fqdn(const struct addrinfo *pai, const char *hostname,
667 const char *servname, struct addrinfo **res)
669 struct addrinfo *result;
670 struct addrinfo *cur;
679 * if the servname does not match socktype/protocol, ignore it.
681 if (get_portmatch(pai, servname) != 0) {
686 if (!_hostconf_init_done)
689 for (i = 0; i < MAXHOSTCONF; i++) {
690 if (!_hostconf[i].byname)
692 error = (*_hostconf[i].byname)(pai, hostname, &result);
695 for (cur = result; cur; cur = cur->ai_next) {
696 GET_PORT(cur, servname);
697 /* canonname should be filled already */
707 freeaddrinfo(result);
713 * passive socket -> anyaddr (0.0.0.0 or ::)
714 * non-passive socket -> localhost (127.0.0.1 or ::1)
717 explore_null(const struct addrinfo *pai, const char *servname,
718 struct addrinfo **res)
721 const struct afd *afd;
722 struct addrinfo *cur;
723 struct addrinfo sentinel;
727 sentinel.ai_next = NULL;
731 * filter out AFs that are not supported by the kernel
734 s = _socket(pai->ai_family, SOCK_DGRAM, 0);
742 * if the servname does not match socktype/protocol, ignore it.
744 if (get_portmatch(pai, servname) != 0)
747 afd = find_afd(pai->ai_family);
751 if (pai->ai_flags & AI_PASSIVE) {
752 GET_AI(cur->ai_next, afd, afd->a_addrany);
754 * GET_CANONNAME(cur->ai_next, "anyaddr");
756 GET_PORT(cur->ai_next, servname);
758 GET_AI(cur->ai_next, afd, afd->a_loopback);
760 * GET_CANONNAME(cur->ai_next, "localhost");
762 GET_PORT(cur->ai_next, servname);
766 *res = sentinel.ai_next;
770 if (sentinel.ai_next)
771 freeaddrinfo(sentinel.ai_next);
779 explore_numeric(const struct addrinfo *pai, const char *hostname,
780 const char *servname, struct addrinfo **res)
782 const struct afd *afd;
783 struct addrinfo *cur;
784 struct addrinfo sentinel;
789 sentinel.ai_next = NULL;
793 * if the servname does not match socktype/protocol, ignore it.
795 if (get_portmatch(pai, servname) != 0)
798 afd = find_afd(pai->ai_family);
803 #if 1 /*X/Open spec*/
805 if (inet_aton(hostname, (struct in_addr *)pton) == 1) {
806 if (pai->ai_family == afd->a_af ||
807 pai->ai_family == PF_UNSPEC /*?*/) {
808 GET_AI(cur->ai_next, afd, pton);
809 GET_PORT(cur->ai_next, servname);
810 while (cur && cur->ai_next)
813 ERR(EAI_FAMILY); /*xxx*/
818 if (inet_pton(afd->a_af, hostname, pton) == 1) {
819 if (pai->ai_family == afd->a_af ||
820 pai->ai_family == PF_UNSPEC /*?*/) {
821 GET_AI(cur->ai_next, afd, pton);
822 GET_PORT(cur->ai_next, servname);
823 while (cur && cur->ai_next)
826 ERR(EAI_FAMILY); /* XXX */
831 *res = sentinel.ai_next;
836 if (sentinel.ai_next)
837 freeaddrinfo(sentinel.ai_next);
842 * numeric hostname with scope
845 explore_numeric_scope(const struct addrinfo *pai, const char *hostname,
846 const char *servname, struct addrinfo **res)
848 #if !defined(SCOPE_DELIMITER) || !defined(INET6)
849 return explore_numeric(pai, hostname, servname, res);
851 const struct afd *afd;
852 struct addrinfo *cur;
854 char *cp, *hostname2 = NULL, *scope, *addr;
855 struct sockaddr_in6 *sin6;
858 * if the servname does not match socktype/protocol, ignore it.
860 if (get_portmatch(pai, servname) != 0)
863 afd = find_afd(pai->ai_family);
867 return explore_numeric(pai, hostname, servname, res);
869 cp = strchr(hostname, SCOPE_DELIMITER);
871 return explore_numeric(pai, hostname, servname, res);
874 * Handle special case of <scoped_address><delimiter><scope id>
876 hostname2 = strdup(hostname);
877 if (hostname2 == NULL)
879 /* terminate at the delimiter */
880 hostname2[cp - hostname] = '\0';
884 error = explore_numeric(pai, addr, servname, res);
888 for (cur = *res; cur; cur = cur->ai_next) {
889 if (cur->ai_family != AF_INET6)
891 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
892 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) {
894 return(EAI_NODATA); /* XXX: is return OK? */
896 sin6->sin6_scope_id = scopeid;
907 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str)
909 if ((pai->ai_flags & AI_CANONNAME) != 0) {
910 ai->ai_canonname = (char *)malloc(strlen(str) + 1);
911 if (ai->ai_canonname == NULL)
913 strlcpy(ai->ai_canonname, str, strlen(str) + 1);
918 static struct addrinfo *
919 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr)
924 struct in6_addr faith_prefix;
931 * Transfrom an IPv4 addr into a special IPv6 addr format for
932 * IPv6->IPv4 translation gateway. (only TCP is supported now)
934 * +-----------------------------------+------------+
935 * | faith prefix part (12 bytes) | embedded |
936 * | | IPv4 addr part (4 bytes)
937 * +-----------------------------------+------------+
939 * faith prefix part is specified as ascii IPv6 addr format
940 * in environmental variable GAI.
941 * For FAITH to work correctly, routing to faith prefix must be
942 * setup toward a machine where a FAITH daemon operates.
943 * Also, the machine must enable some mechanizm
944 * (e.g. faith interface hack) to divert those packet with
945 * faith prefixed destination addr to user-land FAITH daemon.
947 fp_str = getenv("GAI");
948 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 &&
949 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) {
953 memcpy(&v4a, addr, sizeof v4a);
954 v4a_top = v4a >> IN_CLASSA_NSHIFT;
955 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) &&
956 v4a_top != 0 && v4a != IN_LOOPBACKNET) {
957 afd = &afdl[N_INET6];
958 memcpy(&faith_prefix.s6_addr[12], addr,
959 sizeof(struct in_addr));
965 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo)
970 memcpy(ai, pai, sizeof(struct addrinfo));
971 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
972 memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
973 ai->ai_addr->sa_len = afd->a_socklen;
974 ai->ai_addrlen = afd->a_socklen;
975 ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
976 p = (char *)(ai->ai_addr);
979 memcpy(p + afd->a_off, &faith_prefix, afd->a_addrlen);
982 memcpy(p + afd->a_off, addr, afd->a_addrlen);
988 get_portmatch(const struct addrinfo *ai, const char *servname)
991 /* get_port does not touch first argument. when matchonly == 1. */
992 /* LINTED const cast */
993 return get_port((struct addrinfo *)ai, servname, 1);
997 get_port(struct addrinfo *ai, const char *servname, int matchonly)
1004 if (servname == NULL)
1006 switch (ai->ai_family) {
1016 switch (ai->ai_socktype) {
1027 return EAI_SOCKTYPE;
1030 if (str_isnumber(servname)) {
1033 port = atoi(servname);
1034 if (port < 0 || port > 65535)
1038 switch (ai->ai_socktype) {
1050 if ((sp = getservbyname(servname, proto)) == NULL)
1056 switch (ai->ai_family) {
1058 ((struct sockaddr_in *)(void *)
1059 ai->ai_addr)->sin_port = port;
1063 ((struct sockaddr_in6 *)(void *)
1064 ai->ai_addr)->sin6_port = port;
1073 static const struct afd *
1076 const struct afd *afd;
1078 if (af == PF_UNSPEC)
1080 for (afd = afdl; afd->a_af; afd++) {
1081 if (afd->a_af == af)
1088 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend
1089 * will take care of it.
1090 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure
1091 * if the code is right or not.
1093 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with
1097 addrconfig(struct addrinfo *pai)
1103 * Note that implementation dependent test for address
1104 * configuration should be done everytime called
1105 * (or apropriate interval),
1106 * because addresses will be dynamically assigned or deleted.
1108 af = pai->ai_family;
1109 if (af == AF_UNSPEC) {
1110 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
1114 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0)
1121 if (af != AF_UNSPEC) {
1122 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0)
1126 pai->ai_family = af;
1131 /* convert a string to a scope identifier. XXX: IPv6 specific */
1133 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid)
1136 struct in6_addr *a6;
1139 a6 = &sin6->sin6_addr;
1141 /* empty scopeid portion is invalid */
1145 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) {
1147 * We currently assume a one-to-one mapping between links
1148 * and interfaces, so we simply use interface indices for
1149 * like-local scopes.
1151 *scopeid = if_nametoindex(scope);
1157 /* still unclear about literal, allow numeric only - placeholder */
1158 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
1160 if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
1163 goto trynumeric; /* global */
1165 /* try to convert to a numeric id as a last resort */
1168 lscopeid = strtoul(scope, &ep, 10);
1169 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL);
1170 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid)
1179 struct addrinfo *ai;
1184 addr4sort(struct addrinfo *sentinel)
1186 struct addrinfo *ai;
1187 struct addr_ptr *addrs, addr;
1188 struct sockaddr_in *sin;
1195 for (ai = sentinel->ai_next; ai; ai = ai->ai_next)
1198 return 0; /* We don't need sorting. */
1199 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL)
1202 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) {
1203 sin = (struct sockaddr_in *)ai->ai_addr;
1204 for (j = 0; (unsigned)j < _res.nsort; j++) {
1205 if (_res.sort_list[j].addr.s_addr ==
1206 (sin->sin_addr.s_addr & _res.sort_list[j].mask))
1211 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval)
1220 while (needsort < naddrs) {
1221 for (j = needsort - 1; j >= 0; j--) {
1222 if (addrs[j].aval > addrs[j+1].aval) {
1224 addrs[j] = addrs[j + 1];
1225 addrs[j + 1] = addr;
1233 for (i = 0; i < naddrs; ++i) {
1234 ai->ai_next = addrs[i].ai;
1241 #endif /*RESOLVSORT*/
1244 static const char AskedForGot[] =
1245 "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
1248 static struct addrinfo *
1249 getanswer(const querybuf *answer, int anslen, const char *qname, int qtype,
1250 const struct addrinfo *pai)
1252 struct addrinfo sentinel, *cur;
1254 const struct afd *afd;
1261 int type, class, ancount, qdcount;
1262 int haveanswer, had_error;
1263 char tbuf[MAXDNAME];
1264 int (*name_ok) (const char *);
1265 char hostbuf[8*1024];
1267 memset(&sentinel, 0, sizeof(sentinel));
1271 eom = answer->buf + anslen;
1275 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/
1279 return (NULL); /* XXX should be abort(); */
1282 * find first satisfactory answer
1285 ancount = ntohs(hp->ancount);
1286 qdcount = ntohs(hp->qdcount);
1288 ep = hostbuf + sizeof hostbuf;
1289 cp = answer->buf + HFIXEDSZ;
1291 h_errno = NO_RECOVERY;
1294 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1295 if ((n < 0) || !(*name_ok)(bp)) {
1296 h_errno = NO_RECOVERY;
1300 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
1301 /* res_send() has already verified that the query name is the
1302 * same as the one we sent; this just gets the expanded name
1303 * (i.e., with the succeeding search-domain tacked on).
1305 n = strlen(bp) + 1; /* for the \0 */
1306 if (n >= MAXHOSTNAMELEN) {
1307 h_errno = NO_RECOVERY;
1312 /* The qname can be abbreviated, but h_name is now absolute. */
1317 while (ancount-- > 0 && cp < eom && !had_error) {
1318 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1319 if ((n < 0) || !(*name_ok)(bp)) {
1324 type = _getshort(cp);
1325 cp += INT16SZ; /* type */
1326 class = _getshort(cp);
1327 cp += INT16SZ + INT32SZ; /* class, TTL */
1329 cp += INT16SZ; /* len */
1330 if (class != C_IN) {
1331 /* XXX - debug? syslog? */
1333 continue; /* XXX - had_error++ ? */
1335 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
1337 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
1338 if ((n < 0) || !(*name_ok)(tbuf)) {
1343 /* Get canonical name. */
1344 n = strlen(tbuf) + 1; /* for the \0 */
1345 if (n > ep - bp || n >= MAXHOSTNAMELEN) {
1349 strlcpy(bp, tbuf, ep - bp);
1354 if (qtype == T_ANY) {
1355 if (!(type == T_A || type == T_AAAA)) {
1359 } else if (type != qtype) {
1361 if (type != T_KEY && type != T_SIG)
1362 syslog(LOG_NOTICE|LOG_AUTH,
1363 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
1364 qname, p_class(C_IN), p_type(qtype),
1368 continue; /* XXX - had_error++ ? */
1373 if (strcasecmp(canonname, bp) != 0) {
1375 syslog(LOG_NOTICE|LOG_AUTH,
1376 AskedForGot, canonname, bp);
1379 continue; /* XXX - had_error++ ? */
1381 if (type == T_A && n != INADDRSZ) {
1385 if (type == T_AAAA && n != IN6ADDRSZ) {
1389 #ifdef FILTER_V4MAPPED
1390 if (type == T_AAAA) {
1391 struct in6_addr in6;
1392 memcpy(&in6, cp, sizeof(in6));
1393 if (IN6_IS_ADDR_V4MAPPED(&in6)) {
1403 nn = strlen(bp) + 1; /* for the \0 */
1407 /* don't overwrite pai */
1409 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
1410 afd = find_afd(ai.ai_family);
1415 cur->ai_next = get_ai(&ai, afd, (const char *)cp);
1416 if (cur->ai_next == NULL)
1418 while (cur && cur->ai_next)
1429 #if defined(RESOLVSORT)
1431 * We support only IPv4 address for backward
1432 * compatibility against gethostbyname(3).
1434 if (_res.nsort && qtype == T_A) {
1435 if (addr4sort(&sentinel) < 0) {
1436 freeaddrinfo(sentinel.ai_next);
1437 h_errno = NO_RECOVERY;
1441 #endif /*RESOLVSORT*/
1443 get_canonname(pai, sentinel.ai_next, qname);
1445 get_canonname(pai, sentinel.ai_next, canonname);
1446 h_errno = NETDB_SUCCESS;
1447 return sentinel.ai_next;
1450 h_errno = NO_RECOVERY;
1456 _dns_getaddrinfo(const struct addrinfo *pai, const char *hostname,
1457 struct addrinfo **res)
1459 struct addrinfo *ai;
1460 querybuf *buf, *buf2;
1462 struct addrinfo sentinel, *cur;
1463 struct res_target q, q2;
1465 memset(&q, 0, sizeof(q2));
1466 memset(&q2, 0, sizeof(q2));
1467 memset(&sentinel, 0, sizeof(sentinel));
1470 buf = malloc(sizeof(*buf));
1472 h_errno = NETDB_INTERNAL;
1475 buf2 = malloc(sizeof(*buf2));
1478 h_errno = NETDB_INTERNAL;
1482 switch (pai->ai_family) {
1487 q.answer = buf->buf;
1488 q.anslen = sizeof(buf->buf);
1493 q2.answer = buf2->buf;
1494 q2.anslen = sizeof(buf2->buf);
1500 q.answer = buf->buf;
1501 q.anslen = sizeof(buf->buf);
1507 q.answer = buf->buf;
1508 q.anslen = sizeof(buf->buf);
1515 if (res_searchN(hostname, &q) < 0) {
1522 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai);
1525 while (cur && cur->ai_next)
1530 ai = getanswer(buf, q.n, q.name, q.qtype, pai);
1535 if (sentinel.ai_next == NULL)
1537 case HOST_NOT_FOUND:
1544 *res = sentinel.ai_next;
1548 static struct addrinfo *
1549 _gethtent(FILE *hostf, const char *name, const struct addrinfo *pai)
1552 char *cp, *tname, *cname;
1553 struct addrinfo hints, *res0, *res;
1556 char hostbuf[8*1024];
1559 if (!(p = fgets(hostbuf, sizeof hostbuf, hostf)))
1563 if (!(cp = strpbrk(p, "#\n")))
1566 if (!(cp = strpbrk(p, " \t")))
1571 /* if this is not something we're looking for, skip it. */
1573 if (*cp == ' ' || *cp == '\t') {
1580 if ((cp = strpbrk(cp, " \t")) != NULL)
1582 if (strcasecmp(name, tname) == 0)
1588 /* we should not glob socktype/protocol here */
1589 memset(&hints, 0, sizeof(hints));
1590 hints.ai_family = pai->ai_family;
1591 hints.ai_socktype = SOCK_DGRAM;
1592 hints.ai_protocol = 0;
1593 hints.ai_flags = AI_NUMERICHOST;
1594 error = getaddrinfo(addr, "0", &hints, &res0);
1597 #ifdef FILTER_V4MAPPED
1598 /* XXX should check all items in the chain */
1599 if (res0->ai_family == AF_INET6 &&
1600 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) {
1605 for (res = res0; res; res = res->ai_next) {
1607 res->ai_flags = pai->ai_flags;
1608 res->ai_socktype = pai->ai_socktype;
1609 res->ai_protocol = pai->ai_protocol;
1611 if (pai->ai_flags & AI_CANONNAME) {
1612 if (get_canonname(pai, res, cname) != 0) {
1623 _files_getaddrinfo(const struct addrinfo *pai, const char *hostname,
1624 struct addrinfo **res)
1627 struct addrinfo sentinel, *cur;
1630 sentinel.ai_next = NULL;
1633 if ((hostf = fopen(_PATH_HOSTS, "r")) == NULL)
1635 while ((p = _gethtent(hostf, hostname, pai)) != NULL) {
1637 while (cur && cur->ai_next)
1642 if (!sentinel.ai_next)
1645 *res = sentinel.ai_next;
1652 _nis_getaddrinfo(const struct addrinfo *pai, const char *hostname,
1653 struct addrinfo **res)
1657 struct addrinfo sentinel, *cur;
1659 const struct afd *afd;
1662 sentinel.ai_next = NULL;
1665 af = (pai->ai_family == AF_UNSPEC) ? AF_INET : pai->ai_family;
1667 return (EAI_ADDRFAMILY);
1669 if ((hp = _gethostbynisname(hostname, af)) == NULL) {
1671 /* XXX: should be filled in */
1676 } else if (hp->h_name == NULL ||
1677 hp->h_name[0] == 0 || hp->h_addr_list[0] == NULL) {
1685 for (i = 0; hp->h_addr_list[i] != NULL; i++) {
1686 if (hp->h_addrtype != af)
1689 afd = find_afd(hp->h_addrtype);
1693 GET_AI(cur->ai_next, afd, hp->h_addr_list[i]);
1694 if ((pai->ai_flags & AI_CANONNAME) != 0) {
1696 * RFC2553 says that ai_canonname will be set only for
1697 * the first element. we do it for all the elements,
1698 * just for convenience.
1700 GET_CANONNAME(cur->ai_next, hp->h_name);
1703 while (cur && cur->ai_next)
1707 *res = sentinel.ai_next;
1711 if (sentinel.ai_next)
1712 freeaddrinfo(sentinel.ai_next);
1717 /* resolver logic */
1719 extern const char *__hostalias (const char *);
1723 * Formulate a normal query, send, and await answer.
1724 * Returned answer is placed in supplied buffer "answer".
1725 * Perform preliminary check of answer, returning success only
1726 * if no error is indicated and the answer count is nonzero.
1727 * Return the size of the response on success, -1 on error.
1728 * Error number is left in h_errno.
1730 * Caller must parse answer and determine whether it answers the question.
1733 res_queryN(const char *name, /* domain name */
1734 struct res_target *target)
1739 struct res_target *t;
1746 if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
1747 h_errno = NETDB_INTERNAL;
1751 buf = malloc(MAXPACKET);
1753 h_errno = NETDB_INTERNAL;
1757 for (t = target; t; t = t->next) {
1762 hp = (HEADER *)(void *)t->answer;
1763 hp->rcode = NOERROR; /* default */
1765 /* make it easier... */
1771 if (_res.options & RES_DEBUG)
1772 printf(";; res_query(%s, %d, %d)\n", name, class, type);
1775 n = res_mkquery(QUERY, name, class, type, NULL, 0, NULL,
1777 if (n > 0 && (_res.options & RES_USE_EDNS0) != 0)
1778 n = res_opt(n, buf, MAXPACKET, anslen);
1781 if (_res.options & RES_DEBUG)
1782 printf(";; res_query: mkquery failed\n");
1785 h_errno = NO_RECOVERY;
1788 n = res_send(buf, n, answer, anslen);
1792 if (_res.options & RES_DEBUG)
1793 printf(";; res_query: send error\n");
1796 h_errno = TRY_AGAIN;
1801 if (n < 0 || n > anslen)
1802 hp->rcode = FORMERR; /* XXX not very informative */
1803 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
1804 rcode = hp->rcode; /* record most recent error */
1806 if (_res.options & RES_DEBUG)
1807 printf(";; rcode = %u, ancount=%u\n", hp->rcode,
1808 ntohs(hp->ancount));
1813 ancount += ntohs(hp->ancount);
1823 h_errno = HOST_NOT_FOUND;
1826 h_errno = TRY_AGAIN;
1835 h_errno = NO_RECOVERY;
1844 * Formulate a normal query, send, and retrieve answer in supplied buffer.
1845 * Return the size of the response on success, -1 on error.
1846 * If enabled, implement search rules until answer or unrecoverable failure
1847 * is detected. Error code, if any, is left in h_errno.
1850 res_searchN(const char *name, /* domain name */
1851 struct res_target *target)
1853 const char *cp, * const *domain;
1854 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/
1856 int trailing_dot, ret, saved_herrno;
1857 int got_nodata = 0, got_servfail = 0, tried_as_is = 0;
1859 if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
1860 h_errno = NETDB_INTERNAL;
1865 h_errno = HOST_NOT_FOUND; /* default, if we never query */
1867 for (cp = name; *cp; cp++)
1868 dots += (*cp == '.');
1870 if (cp > name && *--cp == '.')
1874 * if there aren't any dots, it could be a user-level alias
1876 if (!dots && (cp = __hostalias(name)) != NULL)
1877 return (res_queryN(cp, target));
1880 * If there are dots in the name already, let's just give it a try
1881 * 'as is'. The threshold can be set with the "ndots" option.
1884 if (dots >= _res.ndots) {
1885 ret = res_querydomainN(name, NULL, target);
1888 saved_herrno = h_errno;
1893 * We do at least one level of search if
1894 * - there is no dot and RES_DEFNAME is set, or
1895 * - there is at least one dot, there is no trailing dot,
1896 * and RES_DNSRCH is set.
1898 if ((!dots && (_res.options & RES_DEFNAMES)) ||
1899 (dots && !trailing_dot && (_res.options & RES_DNSRCH))) {
1902 for (domain = (const char * const *)_res.dnsrch;
1906 ret = res_querydomainN(name, *domain, target);
1911 * If no server present, give up.
1912 * If name isn't found in this domain,
1913 * keep trying higher domains in the search list
1914 * (if that's enabled).
1915 * On a NO_DATA error, keep trying, otherwise
1916 * a wildcard entry of another type could keep us
1917 * from finding this entry higher in the domain.
1918 * If we get some other error (negative answer or
1919 * server failure), then stop searching up,
1920 * but try the input name below in case it's
1923 if (errno == ECONNREFUSED) {
1924 h_errno = TRY_AGAIN;
1932 case HOST_NOT_FOUND:
1936 if (hp->rcode == SERVFAIL) {
1937 /* try next search element, if any */
1943 /* anything else implies that we're done */
1947 * if we got here for some reason other than DNSRCH,
1948 * we only wanted one iteration of the loop, so stop.
1950 if (!(_res.options & RES_DNSRCH))
1956 * if we have not already tried the name "as is", do that now.
1957 * note that we do this regardless of how many dots were in the
1958 * name or whether it ends with a dot.
1960 if (!tried_as_is && (dots || !(_res.options & RES_NOTLDQUERY))) {
1961 ret = res_querydomainN(name, NULL, target);
1967 * if we got here, we didn't satisfy the search.
1968 * if we did an initial full query, return that query's h_errno
1969 * (note that we wouldn't be here if that query had succeeded).
1970 * else if we ever got a nodata, send that back as the reason.
1971 * else send back meaningless h_errno, that being the one from
1972 * the last DNSRCH we did.
1974 if (saved_herrno != -1)
1975 h_errno = saved_herrno;
1976 else if (got_nodata)
1978 else if (got_servfail)
1979 h_errno = TRY_AGAIN;
1984 * Perform a call on res_query on the concatenation of name and domain,
1985 * removing a trailing dot from name if domain is NULL.
1988 res_querydomainN(const char *name, const char *domain,
1989 struct res_target *target)
1991 char nbuf[MAXDNAME];
1992 const char *longname = nbuf;
1995 if ((_res.options & RES_INIT) == 0 && res_init() == -1) {
1996 h_errno = NETDB_INTERNAL;
2000 if (_res.options & RES_DEBUG)
2001 printf(";; res_querydomain(%s, %s)\n",
2002 name, domain?domain:"<Nil>");
2004 if (domain == NULL) {
2006 * Check for trailing '.';
2007 * copy without '.' if present.
2010 if (n >= MAXDNAME) {
2011 h_errno = NO_RECOVERY;
2014 if (n > 0 && name[--n] == '.') {
2015 strncpy(nbuf, name, n);
2022 if (n + d + 1 >= MAXDNAME) {
2023 h_errno = NO_RECOVERY;
2026 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain);
2028 return (res_queryN(longname, target));