1 /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 itojun Exp $ */
4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the project nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * "#ifdef FAITH" part is local hack for supporting IPv4-v6 translator.
35 * Issues to be discussed:
36 * - Return values. There are nonstandard return values defined and used
37 * in the source code. This is because RFC2553 is silent about which error
38 * code must be returned for which situation.
39 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is
40 * invalid. current code - SEGV on freeaddrinfo(NULL)
43 * - The code filters out AFs that are not supported by the kernel,
44 * when globbing NULL hostname (to loopback, or wildcard). Is it the right
45 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG
47 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague.
48 * (1) what should we do against numeric hostname (2) what should we do
49 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready?
50 * non-loopback address configured? global address configured?
52 * OS specific notes for freebsd4:
53 * - FreeBSD supported $GAI. The code does not.
56 #include <sys/cdefs.h>
57 __FBSDID("$FreeBSD$");
59 #include "namespace.h"
60 #include <sys/types.h>
61 #include <sys/param.h>
62 #include <sys/socket.h>
64 #include <netinet/in.h>
65 #include <net/if_types.h>
67 #include <sys/queue.h>
69 #include <net/if_var.h>
70 #include <sys/sysctl.h>
71 #include <sys/ioctl.h>
72 #include <netinet6/in6_var.h>
73 #include <netinet6/nd6.h>
75 #include <arpa/inet.h>
76 #include <arpa/nameser.h>
78 #include <rpcsvc/yp_prot.h>
79 #include <rpcsvc/ypclnt.h>
90 #include "res_config.h"
98 #include "un-namespace.h"
99 #include "libc_private.h"
104 #if defined(__KAME__) && defined(INET6)
112 static const char in_addrany[] = { 0, 0, 0, 0 };
113 static const char in_loopback[] = { 127, 0, 0, 1 };
115 static const char in6_addrany[] = {
116 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
118 static const char in6_loopback[] = {
119 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
124 TAILQ_ENTRY(policyqueue) pc_entry;
126 struct in6_addrpolicy pc_policy;
129 TAILQ_HEAD(policyhead, policyqueue);
131 static const struct afd {
136 const char *a_addrany;
137 const char *a_loopback;
142 {PF_INET6, sizeof(struct in6_addr),
143 sizeof(struct sockaddr_in6),
144 offsetof(struct sockaddr_in6, sin6_addr),
145 in6_addrany, in6_loopback, 1},
150 {PF_INET, sizeof(struct in_addr),
151 sizeof(struct sockaddr_in),
152 offsetof(struct sockaddr_in, sin_addr),
153 in_addrany, in_loopback, 0},
154 {0, 0, 0, 0, NULL, NULL, 0},
162 #define WILD_AF(ex) ((ex)->e_wild & 0x01)
163 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02)
164 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04)
167 static const struct explore explore[] = {
169 { PF_LOCAL, ANY, ANY, 0x01 },
172 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, 0x07 },
173 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, 0x07 },
174 { PF_INET6, SOCK_STREAM, IPPROTO_SCTP, 0x03 },
175 { PF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 },
176 { PF_INET6, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 },
177 { PF_INET6, SOCK_RAW, ANY, 0x05 },
179 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, 0x07 },
180 { PF_INET, SOCK_STREAM, IPPROTO_TCP, 0x07 },
181 { PF_INET, SOCK_STREAM, IPPROTO_SCTP, 0x03 },
182 { PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 },
183 { PF_INET, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 },
184 { PF_INET, SOCK_RAW, ANY, 0x05 },
194 #define AIO_SRCFLAG_DEPRECATED 0x1
198 struct sockaddr_storage aiou_ss;
199 struct sockaddr aiou_sa;
201 #define aio_srcsa aio_src_un.aiou_sa
202 u_int32_t aio_srcflag;
205 struct policyqueue *aio_srcpolicy;
206 struct policyqueue *aio_dstpolicy;
207 struct addrinfo *aio_ai;
211 static const ns_src default_dns_files[] = {
212 { NSSRC_FILES, NS_SUCCESS },
213 { NSSRC_DNS, NS_SUCCESS },
218 struct res_target *next;
219 const char *name; /* domain name */
220 int qclass, qtype; /* class and type of query */
221 u_char *answer; /* buffer to put answer */
222 int anslen; /* size of answer buffer */
223 int n; /* result length */
226 #define MAXPACKET (64*1024)
230 u_char buf[MAXPACKET];
233 static int str2number(const char *, int *);
234 static int explore_copy(const struct addrinfo *, const struct addrinfo *,
236 static int explore_null(const struct addrinfo *,
237 const char *, struct addrinfo **);
238 static int explore_numeric(const struct addrinfo *, const char *,
239 const char *, struct addrinfo **, const char *);
240 static int explore_numeric_scope(const struct addrinfo *, const char *,
241 const char *, struct addrinfo **);
242 static int get_canonname(const struct addrinfo *,
243 struct addrinfo *, const char *);
244 static struct addrinfo *get_ai(const struct addrinfo *,
245 const struct afd *, const char *);
246 static struct addrinfo *copy_ai(const struct addrinfo *);
247 static int get_portmatch(const struct addrinfo *, const char *);
248 static int get_port(struct addrinfo *, const char *, int);
249 static const struct afd *find_afd(int);
250 static int addrconfig(struct addrinfo *);
252 static int is_ifdisabled(char *);
254 static void set_source(struct ai_order *, struct policyhead *);
255 static int comp_dst(const void *, const void *);
257 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *);
259 static int gai_addr2scopetype(struct sockaddr *);
261 static int explore_fqdn(const struct addrinfo *, const char *,
262 const char *, struct addrinfo **);
264 static int reorder(struct addrinfo *);
265 static int get_addrselectpolicy(struct policyhead *);
266 static void free_addrselectpolicy(struct policyhead *);
267 static struct policyqueue *match_addrselectpolicy(struct sockaddr *,
268 struct policyhead *);
269 static int matchlen(struct sockaddr *, struct sockaddr *);
271 static struct addrinfo *getanswer(const querybuf *, int, const char *, int,
272 const struct addrinfo *, res_state);
273 #if defined(RESOLVSORT)
274 static int addr4sort(struct addrinfo *, res_state);
276 static int _dns_getaddrinfo(void *, void *, va_list);
277 static void _sethtent(FILE **);
278 static void _endhtent(FILE **);
279 static struct addrinfo *_gethtent(FILE **, const char *,
280 const struct addrinfo *);
281 static int _files_getaddrinfo(void *, void *, va_list);
283 static struct addrinfo *_yphostent(char *, const struct addrinfo *);
284 static int _yp_getaddrinfo(void *, void *, va_list);
287 static int addrinfo_id_func(char *, size_t *, va_list, void *);
288 static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *);
289 static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *);
292 static int res_queryN(const char *, struct res_target *, res_state);
293 static int res_searchN(const char *, struct res_target *, res_state);
294 static int res_querydomainN(const char *, const char *,
295 struct res_target *, res_state);
297 /* XXX macros that make external reference is BAD. */
299 #define GET_AI(ai, afd, addr) \
301 /* external reference: pai, error, and label free */ \
302 (ai) = get_ai(pai, (afd), (addr)); \
303 if ((ai) == NULL) { \
304 error = EAI_MEMORY; \
307 } while (/*CONSTCOND*/0)
309 #define GET_PORT(ai, serv) \
311 /* external reference: error and label free */ \
312 error = get_port((ai), (serv), 0); \
315 } while (/*CONSTCOND*/0)
317 #define GET_CANONNAME(ai, str) \
319 /* external reference: pai, error and label free */ \
320 error = get_canonname(pai, (ai), (str)); \
323 } while (/*CONSTCOND*/0)
327 /* external reference: error, and label bad */ \
331 } while (/*CONSTCOND*/0)
333 #define MATCH_FAMILY(x, y, w) \
334 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
335 #define MATCH(x, y, w) \
336 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
339 freeaddrinfo(struct addrinfo *ai)
341 struct addrinfo *next;
345 if (ai->ai_canonname)
346 free(ai->ai_canonname);
347 /* no need to free(ai->ai_addr) */
354 str2number(const char *p, int *portp)
363 v = strtoul(p, &ep, 10);
364 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) {
372 getaddrinfo(const char *hostname, const char *servname,
373 const struct addrinfo *hints, struct addrinfo **res)
375 struct addrinfo sentinel;
376 struct addrinfo *cur;
378 struct addrinfo ai, ai0, *afai;
379 struct addrinfo *pai;
380 const struct afd *afd;
381 const struct explore *ex;
382 struct addrinfo *afailist[sizeof(afdl)/sizeof(afdl[0])];
383 struct addrinfo *afai_unspec;
387 /* ensure we return NULL on errors */
390 memset(&ai, 0, sizeof(ai));
392 memset(afailist, 0, sizeof(afailist));
395 memset(&sentinel, 0, sizeof(sentinel));
399 pai->ai_family = PF_UNSPEC;
400 pai->ai_socktype = ANY;
401 pai->ai_protocol = ANY;
403 pai->ai_canonname = NULL;
407 if (hostname == NULL && servname == NULL)
410 /* error check for hints */
411 if (hints->ai_addrlen || hints->ai_canonname ||
412 hints->ai_addr || hints->ai_next)
413 ERR(EAI_BADHINTS); /* xxx */
414 if (hints->ai_flags & ~AI_MASK)
416 switch (hints->ai_family) {
426 memcpy(pai, hints, sizeof(*pai));
429 * if both socktype/protocol are specified, check if they
430 * are meaningful combination.
432 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
433 for (ex = explore; ex->e_af >= 0; ex++) {
434 if (!MATCH_FAMILY(pai->ai_family, ex->e_af,
437 if (!MATCH(pai->ai_socktype, ex->e_socktype,
440 if (!MATCH(pai->ai_protocol, ex->e_protocol,
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);
482 * NULL hostname, or numeric hostname.
483 * If numeric representation of AF1 can be interpreted as FQDN
484 * representation of AF2, we need to think again about the code below.
487 for (afd = afdl; afd->a_af; afd++) {
490 if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1))
493 if (pai->ai_family == PF_UNSPEC)
494 pai->ai_family = afd->a_af;
496 if (hostname == NULL) {
497 error = explore_null(pai, servname,
498 &afailist[afd - afdl]);
501 * Errors from explore_null should be unexpected and
502 * be caught to avoid returning an incomplete result.
507 error = explore_numeric_scope(pai, hostname, servname,
508 &afailist[afd - afdl]);
511 * explore_numeric_scope returns an error for address
512 * families that do not match that of hostname.
513 * Thus we should not catch the error at this moment.
517 if (!error && afailist[afd - afdl])
525 if (hostname == NULL)
526 ERR(EAI_NONAME); /* used to be EAI_NODATA */
527 if (pai->ai_flags & AI_NUMERICHOST)
530 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0))
534 * hostname as alphabetical name.
537 error = explore_fqdn(pai, hostname, servname, &afai_unspec);
540 for (ex = explore; ex->e_af >= 0; ex++) {
543 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
545 if (!MATCH(pai->ai_socktype, ex->e_socktype,
548 if (!MATCH(pai->ai_protocol, ex->e_protocol,
552 if (pai->ai_family == PF_UNSPEC)
553 pai->ai_family = ex->e_af;
554 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
555 pai->ai_socktype = ex->e_socktype;
556 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
557 pai->ai_protocol = ex->e_protocol;
560 * if the servname does not match socktype/protocol, ignore it.
562 if (get_portmatch(pai, servname) != 0)
568 if ((afd = find_afd(pai->ai_family)) == NULL)
570 /* XXX assumes that afd points inside afdl[] */
571 afai = afailist[afd - afdl];
576 error = explore_copy(pai, afai, &cur->ai_next);
580 while (cur && cur->ai_next)
585 * ensure we return either:
586 * - error == 0, non-NULL *res
587 * - error != 0, NULL *res
590 if (sentinel.ai_next) {
592 * If the returned entry is for an active connection,
593 * and the given name is not numeric, reorder the
594 * list, so that the application would try the list
595 * in the most efficient order. Since the head entry
596 * of the original list may contain ai_canonname and
597 * that entry may be moved elsewhere in the new list,
598 * we keep the pointer and will restore it in the new
599 * head entry. (Note that RFC3493 requires the head
600 * entry store it when requested by the caller).
602 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) {
607 sentinel.ai_next->ai_canonname;
608 sentinel.ai_next->ai_canonname = NULL;
609 (void)reorder(&sentinel);
610 if (sentinel.ai_next->ai_canonname ==
612 sentinel.ai_next->ai_canonname
614 } else if (canonname != NULL)
618 *res = sentinel.ai_next;
625 freeaddrinfo(afai_unspec);
626 for (afd = afdl; afd->a_af; afd++) {
627 if (afailist[afd - afdl])
628 freeaddrinfo(afailist[afd - afdl]);
631 if (sentinel.ai_next)
632 freeaddrinfo(sentinel.ai_next);
638 reorder(struct addrinfo *sentinel)
640 struct addrinfo *ai, **aip;
641 struct ai_order *aio;
643 struct policyhead policyhead;
645 /* count the number of addrinfo elements for sorting. */
646 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++)
650 * If the number is small enough, we can skip the reordering process.
655 /* allocate a temporary array for sort and initialization of it. */
656 if ((aio = malloc(sizeof(*aio) * n)) == NULL)
657 return(n); /* give up reordering */
658 memset(aio, 0, sizeof(*aio) * n);
660 /* retrieve address selection policy from the kernel */
661 TAILQ_INIT(&policyhead);
662 if (!get_addrselectpolicy(&policyhead)) {
663 /* no policy is installed into kernel, we don't sort. */
668 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) {
670 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr);
671 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr,
673 set_source(&aio[i], &policyhead);
676 /* perform sorting. */
677 qsort(aio, n, sizeof(*aio), comp_dst);
679 /* reorder the addrinfo chain. */
680 for (i = 0, aip = &sentinel->ai_next; i < n; i++) {
681 *aip = aio[i].aio_ai;
682 aip = &aio[i].aio_ai->ai_next;
686 /* cleanup and return */
688 free_addrselectpolicy(&policyhead);
693 get_addrselectpolicy(struct policyhead *head)
696 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY };
699 struct in6_addrpolicy *pol, *ep;
701 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0)
705 if ((buf = malloc(l)) == NULL)
707 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) {
712 ep = (struct in6_addrpolicy *)(buf + l);
713 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) {
714 struct policyqueue *new;
716 if ((new = malloc(sizeof(*new))) == NULL) {
717 free_addrselectpolicy(head); /* make the list empty */
720 new->pc_policy = *pol;
721 TAILQ_INSERT_TAIL(head, new, pc_entry);
732 free_addrselectpolicy(struct policyhead *head)
734 struct policyqueue *ent, *nent;
736 for (ent = TAILQ_FIRST(head); ent; ent = nent) {
737 nent = TAILQ_NEXT(ent, pc_entry);
738 TAILQ_REMOVE(head, ent, pc_entry);
743 static struct policyqueue *
744 match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head)
747 struct policyqueue *ent, *bestent = NULL;
748 struct in6_addrpolicy *pol;
749 int matchlen, bestmatchlen = -1;
750 u_char *mp, *ep, *k, *p, m;
751 struct sockaddr_in6 key;
753 switch(addr->sa_family) {
755 key = *(struct sockaddr_in6 *)addr;
758 /* convert the address into IPv4-mapped IPv6 address. */
759 memset(&key, 0, sizeof(key));
760 key.sin6_family = AF_INET6;
761 key.sin6_len = sizeof(key);
762 key.sin6_addr.s6_addr[10] = 0xff;
763 key.sin6_addr.s6_addr[11] = 0xff;
764 memcpy(&key.sin6_addr.s6_addr[12],
765 &((struct sockaddr_in *)addr)->sin_addr, 4);
771 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) {
772 pol = &ent->pc_policy;
775 mp = (u_char *)&pol->addrmask.sin6_addr;
776 ep = mp + 16; /* XXX: scope field? */
777 k = (u_char *)&key.sin6_addr;
778 p = (u_char *)&pol->addr.sin6_addr;
779 for (; mp < ep && *mp; mp++, k++, p++) {
782 goto next; /* not match */
783 if (m == 0xff) /* short cut for a typical case */
793 /* matched. check if this is better than the current best. */
794 if (matchlen > bestmatchlen) {
796 bestmatchlen = matchlen;
811 set_source(struct ai_order *aio, struct policyhead *ph)
813 struct addrinfo ai = *aio->aio_ai;
814 struct sockaddr_storage ss;
818 /* set unspec ("no source is available"), just in case */
819 aio->aio_srcsa.sa_family = AF_UNSPEC;
820 aio->aio_srcscope = -1;
822 switch(ai.ai_family) {
828 default: /* ignore unsupported AFs explicitly */
832 /* XXX: make a dummy addrinfo to call connect() */
833 ai.ai_socktype = SOCK_DGRAM;
834 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */
836 memset(&ss, 0, sizeof(ss));
837 memcpy(&ss, ai.ai_addr, ai.ai_addrlen);
838 ai.ai_addr = (struct sockaddr *)&ss;
839 get_port(&ai, "1", 0);
841 /* open a socket to get the source address for the given dst */
842 if ((s = _socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC,
843 ai.ai_protocol)) < 0)
844 return; /* give up */
845 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0)
847 srclen = ai.ai_addrlen;
848 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) {
849 aio->aio_srcsa.sa_family = AF_UNSPEC;
852 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa);
853 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph);
854 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr);
856 if (ai.ai_family == AF_INET6) {
857 struct in6_ifreq ifr6;
860 memset(&ifr6, 0, sizeof(ifr6));
861 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen);
862 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) {
863 flags6 = ifr6.ifr_ifru.ifru_flags6;
864 if ((flags6 & IN6_IFF_DEPRECATED))
865 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED;
876 matchlen(struct sockaddr *src, struct sockaddr *dst)
883 switch (src->sa_family) {
886 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr;
887 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr;
888 addrlen = sizeof(struct in6_addr);
893 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr;
894 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr;
895 addrlen = sizeof(struct in_addr);
903 if ((r = (*d++ ^ *s++)) != 0) {
904 while (r < addrlen * 8) {
915 comp_dst(const void *arg1, const void *arg2)
917 const struct ai_order *dst1 = arg1, *dst2 = arg2;
920 * Rule 1: Avoid unusable destinations.
921 * XXX: we currently do not consider if an appropriate route exists.
923 if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
924 dst2->aio_srcsa.sa_family == AF_UNSPEC) {
927 if (dst1->aio_srcsa.sa_family == AF_UNSPEC &&
928 dst2->aio_srcsa.sa_family != AF_UNSPEC) {
932 /* Rule 2: Prefer matching scope. */
933 if (dst1->aio_dstscope == dst1->aio_srcscope &&
934 dst2->aio_dstscope != dst2->aio_srcscope) {
937 if (dst1->aio_dstscope != dst1->aio_srcscope &&
938 dst2->aio_dstscope == dst2->aio_srcscope) {
942 /* Rule 3: Avoid deprecated addresses. */
943 if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
944 dst2->aio_srcsa.sa_family != AF_UNSPEC) {
945 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
946 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
949 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
950 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
955 /* Rule 4: Prefer home addresses. */
956 /* XXX: not implemented yet */
958 /* Rule 5: Prefer matching label. */
960 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy &&
961 dst1->aio_srcpolicy->pc_policy.label ==
962 dst1->aio_dstpolicy->pc_policy.label &&
963 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL ||
964 dst2->aio_srcpolicy->pc_policy.label !=
965 dst2->aio_dstpolicy->pc_policy.label)) {
968 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy &&
969 dst2->aio_srcpolicy->pc_policy.label ==
970 dst2->aio_dstpolicy->pc_policy.label &&
971 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL ||
972 dst1->aio_srcpolicy->pc_policy.label !=
973 dst1->aio_dstpolicy->pc_policy.label)) {
978 /* Rule 6: Prefer higher precedence. */
980 if (dst1->aio_dstpolicy &&
981 (dst2->aio_dstpolicy == NULL ||
982 dst1->aio_dstpolicy->pc_policy.preced >
983 dst2->aio_dstpolicy->pc_policy.preced)) {
986 if (dst2->aio_dstpolicy &&
987 (dst1->aio_dstpolicy == NULL ||
988 dst2->aio_dstpolicy->pc_policy.preced >
989 dst1->aio_dstpolicy->pc_policy.preced)) {
994 /* Rule 7: Prefer native transport. */
995 /* XXX: not implemented yet */
997 /* Rule 8: Prefer smaller scope. */
998 if (dst1->aio_dstscope >= 0 &&
999 dst1->aio_dstscope < dst2->aio_dstscope) {
1002 if (dst2->aio_dstscope >= 0 &&
1003 dst2->aio_dstscope < dst1->aio_dstscope) {
1008 * Rule 9: Use longest matching prefix.
1009 * We compare the match length in a same AF only.
1011 if (dst1->aio_ai->ai_addr->sa_family ==
1012 dst2->aio_ai->ai_addr->sa_family &&
1013 dst1->aio_ai->ai_addr->sa_family != AF_INET) {
1014 if (dst1->aio_matchlen > dst2->aio_matchlen) {
1017 if (dst1->aio_matchlen < dst2->aio_matchlen) {
1022 /* Rule 10: Otherwise, leave the order unchanged. */
1027 * Copy from scope.c.
1028 * XXX: we should standardize the functions and link them as standard
1032 gai_addr2scopetype(struct sockaddr *sa)
1035 struct sockaddr_in6 *sa6;
1037 struct sockaddr_in *sa4;
1039 switch(sa->sa_family) {
1042 sa6 = (struct sockaddr_in6 *)sa;
1043 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
1044 /* just use the scope field of the multicast address */
1045 return(sa6->sin6_addr.s6_addr[2] & 0x0f);
1048 * Unicast addresses: map scope type to corresponding scope
1049 * value defined for multcast addresses.
1050 * XXX: hardcoded scope type values are bad...
1052 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr))
1053 return(1); /* node local scope */
1054 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr))
1055 return(2); /* link-local scope */
1056 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr))
1057 return(5); /* site-local scope */
1058 return(14); /* global scope */
1063 * IPv4 pseudo scoping according to RFC 3484.
1065 sa4 = (struct sockaddr_in *)sa;
1066 /* IPv4 autoconfiguration addresses have link-local scope. */
1067 if (((u_char *)&sa4->sin_addr)[0] == 169 &&
1068 ((u_char *)&sa4->sin_addr)[1] == 254)
1070 /* Private addresses have site-local scope. */
1071 if (((u_char *)&sa4->sin_addr)[0] == 10 ||
1072 (((u_char *)&sa4->sin_addr)[0] == 172 &&
1073 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) ||
1074 (((u_char *)&sa4->sin_addr)[0] == 192 &&
1075 ((u_char *)&sa4->sin_addr)[1] == 168))
1076 return(14); /* XXX: It should be 5 unless NAT */
1077 /* Loopback addresses have link-local scope. */
1078 if (((u_char *)&sa4->sin_addr)[0] == 127)
1083 errno = EAFNOSUPPORT; /* is this a good error? */
1089 explore_copy(const struct addrinfo *pai, const struct addrinfo *src0,
1090 struct addrinfo **res)
1093 struct addrinfo sentinel, *cur;
1094 const struct addrinfo *src;
1097 sentinel.ai_next = NULL;
1100 for (src = src0; src != NULL; src = src->ai_next) {
1101 if (src->ai_family != pai->ai_family)
1104 cur->ai_next = copy_ai(src);
1105 if (!cur->ai_next) {
1110 cur->ai_next->ai_socktype = pai->ai_socktype;
1111 cur->ai_next->ai_protocol = pai->ai_protocol;
1115 *res = sentinel.ai_next;
1119 freeaddrinfo(sentinel.ai_next);
1125 * passive socket -> anyaddr (0.0.0.0 or ::)
1126 * non-passive socket -> localhost (127.0.0.1 or ::1)
1129 explore_null(const struct addrinfo *pai, const char *servname,
1130 struct addrinfo **res)
1133 const struct afd *afd;
1134 struct addrinfo *ai;
1141 * filter out AFs that are not supported by the kernel
1144 s = _socket(pai->ai_family, SOCK_DGRAM | SOCK_CLOEXEC, 0);
1146 if (errno != EMFILE)
1151 afd = find_afd(pai->ai_family);
1155 if (pai->ai_flags & AI_PASSIVE) {
1156 GET_AI(ai, afd, afd->a_addrany);
1157 GET_PORT(ai, servname);
1159 GET_AI(ai, afd, afd->a_loopback);
1160 GET_PORT(ai, servname);
1176 explore_numeric(const struct addrinfo *pai, const char *hostname,
1177 const char *servname, struct addrinfo **res, const char *canonname)
1179 const struct afd *afd;
1180 struct addrinfo *ai;
1182 char pton[PTON_MAX];
1187 afd = find_afd(pai->ai_family);
1191 switch (afd->a_af) {
1194 * RFC3493 requires getaddrinfo() to accept AF_INET formats
1195 * that are accepted by inet_addr() and its family. The
1196 * accepted forms includes the "classful" one, which inet_pton
1197 * does not accept. So we need to separate the case for
1200 if (inet_aton(hostname, (struct in_addr *)pton) != 1)
1204 if (inet_pton(afd->a_af, hostname, pton) != 1)
1209 if (pai->ai_family == afd->a_af) {
1210 GET_AI(ai, afd, pton);
1211 GET_PORT(ai, servname);
1212 if ((pai->ai_flags & AI_CANONNAME)) {
1214 * Set the numeric address itself as the canonical
1215 * name, based on a clarification in RFC3493.
1217 GET_CANONNAME(ai, canonname);
1221 * XXX: This should not happen since we already matched the AF
1238 * numeric hostname with scope
1241 explore_numeric_scope(const struct addrinfo *pai, const char *hostname,
1242 const char *servname, struct addrinfo **res)
1244 #if !defined(SCOPE_DELIMITER) || !defined(INET6)
1245 return explore_numeric(pai, hostname, servname, res, hostname);
1247 const struct afd *afd;
1248 struct addrinfo *cur;
1250 char *cp, *hostname2 = NULL, *scope, *addr;
1251 struct sockaddr_in6 *sin6;
1253 afd = find_afd(pai->ai_family);
1258 return explore_numeric(pai, hostname, servname, res, hostname);
1260 cp = strchr(hostname, SCOPE_DELIMITER);
1262 return explore_numeric(pai, hostname, servname, res, hostname);
1265 * Handle special case of <scoped_address><delimiter><scope id>
1267 hostname2 = strdup(hostname);
1268 if (hostname2 == NULL)
1270 /* terminate at the delimiter */
1271 hostname2[cp - hostname] = '\0';
1275 error = explore_numeric(pai, addr, servname, res, hostname);
1279 for (cur = *res; cur; cur = cur->ai_next) {
1280 if (cur->ai_family != AF_INET6)
1282 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
1283 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) {
1287 return(EAI_NONAME); /* XXX: is return OK? */
1289 sin6->sin6_scope_id = scopeid;
1295 if (error && *res) {
1304 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str)
1306 if ((pai->ai_flags & AI_CANONNAME) != 0) {
1307 ai->ai_canonname = strdup(str);
1308 if (ai->ai_canonname == NULL)
1314 static struct addrinfo *
1315 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr)
1318 struct addrinfo *ai;
1320 struct in6_addr faith_prefix;
1327 * Transfrom an IPv4 addr into a special IPv6 addr format for
1328 * IPv6->IPv4 translation gateway. (only TCP is supported now)
1330 * +-----------------------------------+------------+
1331 * | faith prefix part (12 bytes) | embedded |
1332 * | | IPv4 addr part (4 bytes)
1333 * +-----------------------------------+------------+
1335 * faith prefix part is specified as ascii IPv6 addr format
1336 * in environmental variable GAI.
1337 * For FAITH to work correctly, routing to faith prefix must be
1338 * setup toward a machine where a FAITH daemon operates.
1339 * Also, the machine must enable some mechanizm
1340 * (e.g. faith interface hack) to divert those packet with
1341 * faith prefixed destination addr to user-land FAITH daemon.
1343 fp_str = getenv("GAI");
1344 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 &&
1345 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) {
1349 memcpy(&v4a, addr, sizeof v4a);
1350 v4a_top = v4a >> IN_CLASSA_NSHIFT;
1351 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) &&
1352 v4a_top != 0 && v4a != IN_LOOPBACKNET) {
1353 afd = &afdl[N_INET6];
1354 memcpy(&faith_prefix.s6_addr[12], addr,
1355 sizeof(struct in_addr));
1361 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo)
1362 + (afd->a_socklen));
1366 memcpy(ai, pai, sizeof(struct addrinfo));
1367 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
1368 memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
1369 ai->ai_addr->sa_len = afd->a_socklen;
1370 ai->ai_addrlen = afd->a_socklen;
1371 ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
1372 p = (char *)(void *)(ai->ai_addr);
1375 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen);
1378 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen);
1382 /* XXX need to malloc() the same way we do from other functions! */
1383 static struct addrinfo *
1384 copy_ai(const struct addrinfo *pai)
1386 struct addrinfo *ai;
1389 l = sizeof(*ai) + pai->ai_addrlen;
1390 if ((ai = (struct addrinfo *)malloc(l)) == NULL)
1393 memcpy(ai, pai, sizeof(*ai));
1394 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
1395 memcpy(ai->ai_addr, pai->ai_addr, pai->ai_addrlen);
1397 if (pai->ai_canonname) {
1398 l = strlen(pai->ai_canonname) + 1;
1399 if ((ai->ai_canonname = malloc(l)) == NULL) {
1403 strlcpy(ai->ai_canonname, pai->ai_canonname, l);
1405 /* just to make sure */
1406 ai->ai_canonname = NULL;
1415 get_portmatch(const struct addrinfo *ai, const char *servname)
1418 /* get_port does not touch first argument when matchonly == 1. */
1419 /* LINTED const cast */
1420 return get_port((struct addrinfo *)ai, servname, 1);
1424 get_port(struct addrinfo *ai, const char *servname, int matchonly)
1431 if (servname == NULL)
1433 switch (ai->ai_family) {
1443 switch (ai->ai_socktype) {
1448 case SOCK_SEQPACKET:
1452 switch (ai->ai_family) {
1465 return EAI_SOCKTYPE;
1468 error = str2number(servname, &port);
1472 if (port < 0 || port > 65535)
1476 if (ai->ai_flags & AI_NUMERICSERV)
1479 switch (ai->ai_protocol) {
1489 case IPPROTO_UDPLITE:
1497 if ((sp = getservbyname(servname, proto)) == NULL)
1503 switch (ai->ai_family) {
1505 ((struct sockaddr_in *)(void *)
1506 ai->ai_addr)->sin_port = port;
1510 ((struct sockaddr_in6 *)(void *)
1511 ai->ai_addr)->sin6_port = port;
1520 static const struct afd *
1523 const struct afd *afd;
1525 if (af == PF_UNSPEC)
1527 for (afd = afdl; afd->a_af; afd++) {
1528 if (afd->a_af == af)
1535 * post-2553: AI_ADDRCONFIG check. Determines which address families are
1536 * configured on the local system and correlates with pai->ai_family value.
1537 * If an address family is not configured on the system, it will not be
1538 * queried for. For this purpose, loopback addresses are not considered
1539 * configured addresses.
1541 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with
1545 addrconfig(struct addrinfo *pai)
1547 struct ifaddrs *ifaddrs, *ifa;
1548 int seen_inet = 0, seen_inet6 = 0;
1550 if (getifaddrs(&ifaddrs) != 0)
1553 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) {
1554 if (ifa->ifa_addr == NULL || (ifa->ifa_flags & IFF_UP) == 0)
1556 if ((ifa->ifa_flags & IFT_LOOP) != 0)
1558 switch (ifa->ifa_addr->sa_family) {
1564 if (!seen_inet6 && !is_ifdisabled(ifa->ifa_name))
1570 freeifaddrs(ifaddrs);
1572 switch(pai->ai_family) {
1578 if (seen_inet == seen_inet6)
1580 pai->ai_family = seen_inet ? AF_INET : AF_INET6;
1588 is_ifdisabled(char *name)
1590 struct in6_ndireq nd;
1593 if ((fd = _socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, 0)) < 0)
1595 memset(&nd, 0, sizeof(nd));
1596 strlcpy(nd.ifname, name, sizeof(nd.ifname));
1597 if (_ioctl(fd, SIOCGIFINFO_IN6, &nd) < 0) {
1602 return ((nd.ndi.flags & ND6_IFF_IFDISABLED) != 0);
1605 /* convert a string to a scope identifier. XXX: IPv6 specific */
1607 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid)
1610 struct in6_addr *a6;
1613 a6 = &sin6->sin6_addr;
1615 /* empty scopeid portion is invalid */
1619 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) ||
1620 IN6_IS_ADDR_MC_NODELOCAL(a6)) {
1622 * We currently assume a one-to-one mapping between links
1623 * and interfaces, so we simply use interface indices for
1624 * like-local scopes.
1626 *scopeid = if_nametoindex(scope);
1632 /* still unclear about literal, allow numeric only - placeholder */
1633 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
1635 if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
1638 goto trynumeric; /* global */
1640 /* try to convert to a numeric id as a last resort */
1643 lscopeid = strtoul(scope, &ep, 10);
1644 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL);
1645 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid)
1655 addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap,
1661 const int op_id = 0; /* identifies the getaddrinfo for the cache */
1663 struct addrinfo *hints;
1666 int ai_flags, ai_family, ai_socktype, ai_protocol;
1667 size_t desired_size, size;
1669 statp = __res_state();
1670 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES |
1671 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6);
1673 hostname = va_arg(ap, char *);
1674 hints = va_arg(ap, struct addrinfo *);
1676 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4;
1677 if (hostname != NULL) {
1678 size = strlen(hostname);
1679 desired_size += size + 1;
1683 if (desired_size > *buffer_size) {
1684 *buffer_size = desired_size;
1689 ai_flags = ai_family = ai_socktype = ai_protocol = 0;
1691 ai_flags = hints->ai_flags;
1692 ai_family = hints->ai_family;
1693 ai_socktype = hints->ai_socktype;
1694 ai_protocol = hints->ai_protocol;
1698 memcpy(p, &res_options, sizeof(res_options));
1699 p += sizeof(res_options);
1701 memcpy(p, &op_id, sizeof(int));
1704 memcpy(p, &ai_flags, sizeof(int));
1707 memcpy(p, &ai_family, sizeof(int));
1710 memcpy(p, &ai_socktype, sizeof(int));
1713 memcpy(p, &ai_protocol, sizeof(int));
1716 if (hostname != NULL)
1717 memcpy(p, hostname, size);
1719 *buffer_size = desired_size;
1720 return (NS_SUCCESS);
1724 addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval,
1725 va_list ap, void *cache_mdata)
1727 struct addrinfo *ai, *cai;
1729 size_t desired_size, size, ai_size;
1731 ai = *((struct addrinfo **)retval);
1733 desired_size = sizeof(size_t);
1735 for (cai = ai; cai != NULL; cai = cai->ai_next) {
1736 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen;
1737 if (cai->ai_canonname != NULL)
1738 desired_size += sizeof(size_t) +
1739 strlen(cai->ai_canonname);
1743 if (desired_size > *buffer_size) {
1744 /* this assignment is here for future use */
1746 *buffer_size = desired_size;
1750 memset(buffer, 0, desired_size);
1753 memcpy(p, &ai_size, sizeof(size_t));
1754 p += sizeof(size_t);
1755 for (cai = ai; cai != NULL; cai = cai->ai_next) {
1756 memcpy(p, cai, sizeof(struct addrinfo));
1757 p += sizeof(struct addrinfo);
1759 memcpy(p, cai->ai_addr, cai->ai_addrlen);
1760 p += cai->ai_addrlen;
1762 if (cai->ai_canonname != NULL) {
1763 size = strlen(cai->ai_canonname);
1764 memcpy(p, &size, sizeof(size_t));
1765 p += sizeof(size_t);
1767 memcpy(p, cai->ai_canonname, size);
1772 return (NS_SUCCESS);
1776 addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval,
1777 va_list ap, void *cache_mdata)
1779 struct addrinfo new_ai, *result, *sentinel, *lasts;
1782 size_t ai_size, ai_i, size;
1785 memcpy(&ai_size, p, sizeof(size_t));
1786 p += sizeof(size_t);
1790 for (ai_i = 0; ai_i < ai_size; ++ai_i) {
1791 memcpy(&new_ai, p, sizeof(struct addrinfo));
1792 p += sizeof(struct addrinfo);
1793 size = new_ai.ai_addrlen + sizeof(struct addrinfo) +
1796 sentinel = (struct addrinfo *)malloc(size);
1797 memset(sentinel, 0, size);
1799 memcpy(sentinel, &new_ai, sizeof(struct addrinfo));
1800 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel +
1801 sizeof(struct addrinfo));
1803 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen);
1804 p += new_ai.ai_addrlen;
1806 if (new_ai.ai_canonname != NULL) {
1807 memcpy(&size, p, sizeof(size_t));
1808 p += sizeof(size_t);
1810 sentinel->ai_canonname = (char *)malloc(size + 1);
1811 memset(sentinel->ai_canonname, 0, size + 1);
1813 memcpy(sentinel->ai_canonname, p, size);
1817 if (result == NULL) {
1821 lasts->ai_next = sentinel;
1826 *((struct addrinfo **)retval) = result;
1827 return (NS_SUCCESS);
1829 #endif /* NS_CACHING */
1832 * FQDN hostname, DNS lookup
1835 explore_fqdn(const struct addrinfo *pai, const char *hostname,
1836 const char *servname, struct addrinfo **res)
1838 struct addrinfo *result;
1839 struct addrinfo *cur;
1843 static const nss_cache_info cache_info =
1844 NS_COMMON_CACHE_INFO_INITIALIZER(
1845 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func,
1846 addrinfo_unmarshal_func);
1848 static const ns_dtab dtab[] = {
1849 NS_FILES_CB(_files_getaddrinfo, NULL)
1850 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */
1851 NS_NIS_CB(_yp_getaddrinfo, NULL)
1853 NS_CACHE_CB(&cache_info)
1861 * if the servname does not match socktype/protocol, ignore it.
1863 if (get_portmatch(pai, servname) != 0)
1866 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo",
1867 default_dns_files, hostname, pai)) {
1879 for (cur = result; cur; cur = cur->ai_next) {
1880 GET_PORT(cur, servname);
1881 /* canonname should be filled already */
1892 freeaddrinfo(result);
1897 static const char AskedForGot[] =
1898 "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
1901 static struct addrinfo *
1902 getanswer(const querybuf *answer, int anslen, const char *qname, int qtype,
1903 const struct addrinfo *pai, res_state res)
1905 struct addrinfo sentinel, *cur;
1907 const struct afd *afd;
1914 int type, class, ancount, qdcount;
1915 int haveanswer, had_error;
1916 char tbuf[MAXDNAME];
1917 int (*name_ok)(const char *);
1918 char hostbuf[8*1024];
1920 memset(&sentinel, 0, sizeof(sentinel));
1924 eom = answer->buf + anslen;
1928 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/
1932 return (NULL); /* XXX should be abort(); */
1935 * find first satisfactory answer
1938 ancount = ntohs(hp->ancount);
1939 qdcount = ntohs(hp->qdcount);
1941 ep = hostbuf + sizeof hostbuf;
1942 cp = answer->buf + HFIXEDSZ;
1944 RES_SET_H_ERRNO(res, NO_RECOVERY);
1947 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1948 if ((n < 0) || !(*name_ok)(bp)) {
1949 RES_SET_H_ERRNO(res, NO_RECOVERY);
1953 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
1954 /* res_send() has already verified that the query name is the
1955 * same as the one we sent; this just gets the expanded name
1956 * (i.e., with the succeeding search-domain tacked on).
1958 n = strlen(bp) + 1; /* for the \0 */
1959 if (n >= MAXHOSTNAMELEN) {
1960 RES_SET_H_ERRNO(res, NO_RECOVERY);
1965 /* The qname can be abbreviated, but h_name is now absolute. */
1970 while (ancount-- > 0 && cp < eom && !had_error) {
1971 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1972 if ((n < 0) || !(*name_ok)(bp)) {
1977 type = _getshort(cp);
1978 cp += INT16SZ; /* type */
1979 class = _getshort(cp);
1980 cp += INT16SZ + INT32SZ; /* class, TTL */
1982 cp += INT16SZ; /* len */
1983 if (class != C_IN) {
1984 /* XXX - debug? syslog? */
1986 continue; /* XXX - had_error++ ? */
1988 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
1990 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
1991 if ((n < 0) || !(*name_ok)(tbuf)) {
1996 /* Get canonical name. */
1997 n = strlen(tbuf) + 1; /* for the \0 */
1998 if (n > ep - bp || n >= MAXHOSTNAMELEN) {
2002 strlcpy(bp, tbuf, ep - bp);
2007 if (qtype == T_ANY) {
2008 if (!(type == T_A || type == T_AAAA)) {
2012 } else if (type != qtype) {
2014 if (type != T_KEY && type != T_SIG &&
2016 syslog(LOG_NOTICE|LOG_AUTH,
2017 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
2018 qname, p_class(C_IN), p_type(qtype),
2022 continue; /* XXX - had_error++ ? */
2027 if (strcasecmp(canonname, bp) != 0) {
2029 syslog(LOG_NOTICE|LOG_AUTH,
2030 AskedForGot, canonname, bp);
2033 continue; /* XXX - had_error++ ? */
2035 if (type == T_A && n != INADDRSZ) {
2039 if (type == T_AAAA && n != IN6ADDRSZ) {
2043 #ifdef FILTER_V4MAPPED
2044 if (type == T_AAAA) {
2045 struct in6_addr in6;
2046 memcpy(&in6, cp, sizeof(in6));
2047 if (IN6_IS_ADDR_V4MAPPED(&in6)) {
2057 nn = strlen(bp) + 1; /* for the \0 */
2061 /* don't overwrite pai */
2063 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
2064 afd = find_afd(ai.ai_family);
2069 cur->ai_next = get_ai(&ai, afd, (const char *)cp);
2070 if (cur->ai_next == NULL)
2072 while (cur && cur->ai_next)
2083 #if defined(RESOLVSORT)
2085 * We support only IPv4 address for backward
2086 * compatibility against gethostbyname(3).
2088 if (res->nsort && qtype == T_A) {
2089 if (addr4sort(&sentinel, res) < 0) {
2090 freeaddrinfo(sentinel.ai_next);
2091 RES_SET_H_ERRNO(res, NO_RECOVERY);
2095 #endif /*RESOLVSORT*/
2097 (void)get_canonname(pai, sentinel.ai_next, qname);
2099 (void)get_canonname(pai, sentinel.ai_next, canonname);
2100 RES_SET_H_ERRNO(res, NETDB_SUCCESS);
2101 return sentinel.ai_next;
2104 RES_SET_H_ERRNO(res, NO_RECOVERY);
2110 struct addrinfo *ai;
2115 addr4sort(struct addrinfo *sentinel, res_state res)
2117 struct addrinfo *ai;
2118 struct addr_ptr *addrs, addr;
2119 struct sockaddr_in *sin;
2126 for (ai = sentinel->ai_next; ai; ai = ai->ai_next)
2129 return 0; /* We don't need sorting. */
2130 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL)
2133 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) {
2134 sin = (struct sockaddr_in *)ai->ai_addr;
2135 for (j = 0; (unsigned)j < res->nsort; j++) {
2136 if (res->sort_list[j].addr.s_addr ==
2137 (sin->sin_addr.s_addr & res->sort_list[j].mask))
2142 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval)
2151 while (needsort < naddrs) {
2152 for (j = needsort - 1; j >= 0; j--) {
2153 if (addrs[j].aval > addrs[j+1].aval) {
2155 addrs[j] = addrs[j + 1];
2156 addrs[j + 1] = addr;
2164 for (i = 0; i < naddrs; ++i) {
2165 ai->ai_next = addrs[i].ai;
2172 #endif /*RESOLVSORT*/
2176 _dns_getaddrinfo(void *rv, void *cb_data, va_list ap)
2178 struct addrinfo *ai;
2179 querybuf *buf, *buf2;
2180 const char *hostname;
2181 const struct addrinfo *pai;
2182 struct addrinfo sentinel, *cur;
2183 struct res_target q, q2;
2186 hostname = va_arg(ap, char *);
2187 pai = va_arg(ap, const struct addrinfo *);
2189 memset(&q, 0, sizeof(q));
2190 memset(&q2, 0, sizeof(q2));
2191 memset(&sentinel, 0, sizeof(sentinel));
2194 buf = malloc(sizeof(*buf));
2196 RES_SET_H_ERRNO(res, NETDB_INTERNAL);
2199 buf2 = malloc(sizeof(*buf2));
2202 RES_SET_H_ERRNO(res, NETDB_INTERNAL);
2206 switch (pai->ai_family) {
2211 q.answer = buf->buf;
2212 q.anslen = sizeof(buf->buf);
2217 q2.answer = buf2->buf;
2218 q2.anslen = sizeof(buf2->buf);
2224 q.answer = buf->buf;
2225 q.anslen = sizeof(buf->buf);
2231 q.answer = buf->buf;
2232 q.anslen = sizeof(buf->buf);
2240 res = __res_state();
2241 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) {
2242 RES_SET_H_ERRNO(res, NETDB_INTERNAL);
2248 if (res_searchN(hostname, &q, res) < 0) {
2255 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res);
2258 while (cur && cur->ai_next)
2262 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res);
2267 if (sentinel.ai_next == NULL)
2268 switch (res->res_h_errno) {
2269 case HOST_NOT_FOUND:
2276 *((struct addrinfo **)rv) = sentinel.ai_next;
2281 _sethtent(FILE **hostf)
2284 *hostf = fopen(_PATH_HOSTS, "re");
2290 _endhtent(FILE **hostf)
2293 (void) fclose(*hostf);
2298 static struct addrinfo *
2299 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai)
2302 char *cp, *tname, *cname;
2303 struct addrinfo hints, *res0, *res;
2306 char hostbuf[8*1024];
2308 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re")))
2311 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf)))
2315 cp = strpbrk(p, "#\n");
2318 if (!(cp = strpbrk(p, " \t")))
2323 /* if this is not something we're looking for, skip it. */
2325 if (*cp == ' ' || *cp == '\t') {
2332 if ((cp = strpbrk(cp, " \t")) != NULL)
2334 if (strcasecmp(name, tname) == 0)
2340 /* we should not glob socktype/protocol here */
2341 memset(&hints, 0, sizeof(hints));
2342 hints.ai_family = pai->ai_family;
2343 hints.ai_socktype = SOCK_DGRAM;
2344 hints.ai_protocol = 0;
2345 hints.ai_flags = AI_NUMERICHOST;
2346 error = getaddrinfo(addr, "0", &hints, &res0);
2349 #ifdef FILTER_V4MAPPED
2350 /* XXX should check all items in the chain */
2351 if (res0->ai_family == AF_INET6 &&
2352 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) {
2357 for (res = res0; res; res = res->ai_next) {
2359 res->ai_flags = pai->ai_flags;
2360 res->ai_socktype = pai->ai_socktype;
2361 res->ai_protocol = pai->ai_protocol;
2363 if (pai->ai_flags & AI_CANONNAME) {
2364 if (get_canonname(pai, res, cname) != 0) {
2375 _files_getaddrinfo(void *rv, void *cb_data, va_list ap)
2378 const struct addrinfo *pai;
2379 struct addrinfo sentinel, *cur;
2383 name = va_arg(ap, char *);
2384 pai = va_arg(ap, struct addrinfo *);
2386 memset(&sentinel, 0, sizeof(sentinel));
2390 while ((p = _gethtent(&hostf, name, pai)) != NULL) {
2392 while (cur && cur->ai_next)
2397 *((struct addrinfo **)rv) = sentinel.ai_next;
2398 if (sentinel.ai_next == NULL)
2405 static struct addrinfo *
2406 _yphostent(char *line, const struct addrinfo *pai)
2408 struct addrinfo sentinel, *cur;
2409 struct addrinfo hints, *res, *res0;
2412 const char *addr, *canonname;
2416 addr = canonname = NULL;
2418 memset(&sentinel, 0, sizeof(sentinel));
2422 /* terminate line */
2423 cp = strchr(p, '\n');
2430 cp = strpbrk(p, " \t");
2432 if (canonname == NULL)
2442 if (*cp == ' ' || *cp == '\t') {
2448 if ((cp = strpbrk(cp, " \t")) != NULL)
2453 hints.ai_flags = AI_NUMERICHOST;
2454 error = getaddrinfo(addr, NULL, &hints, &res0);
2456 for (res = res0; res; res = res->ai_next) {
2458 res->ai_flags = pai->ai_flags;
2460 if (pai->ai_flags & AI_CANONNAME)
2461 (void)get_canonname(pai, res, canonname);
2466 cur->ai_next = res0;
2467 while (cur && cur->ai_next)
2477 return sentinel.ai_next;
2482 _yp_getaddrinfo(void *rv, void *cb_data, va_list ap)
2484 struct addrinfo sentinel, *cur;
2485 struct addrinfo *ai = NULL;
2489 const struct addrinfo *pai;
2492 if (_yp_check(&ypdomain) == 0)
2495 name = va_arg(ap, char *);
2496 pai = va_arg(ap, const struct addrinfo *);
2498 memset(&sentinel, 0, sizeof(sentinel));
2501 /* hosts.byname is only for IPv4 (Solaris8) */
2502 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) {
2503 r = yp_match(ypdomain, "hosts.byname", name,
2504 (int)strlen(name), &ypbuf, &ypbuflen);
2506 struct addrinfo ai4;
2509 ai4.ai_family = AF_INET;
2510 ai = _yphostent(ypbuf, &ai4);
2513 while (cur && cur->ai_next)
2520 /* ipnodes.byname can hold both IPv4/v6 */
2521 r = yp_match(ypdomain, "ipnodes.byname", name,
2522 (int)strlen(name), &ypbuf, &ypbuflen);
2524 ai = _yphostent(ypbuf, pai);
2530 if (sentinel.ai_next == NULL) {
2531 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND);
2534 *((struct addrinfo **)rv) = sentinel.ai_next;
2539 /* resolver logic */
2542 * Formulate a normal query, send, and await answer.
2543 * Returned answer is placed in supplied buffer "answer".
2544 * Perform preliminary check of answer, returning success only
2545 * if no error is indicated and the answer count is nonzero.
2546 * Return the size of the response on success, -1 on error.
2547 * Error number is left in h_errno.
2549 * Caller must parse answer and determine whether it answers the question.
2552 res_queryN(const char *name, struct res_target *target, res_state res)
2558 struct res_target *t;
2565 buf = malloc(MAXPACKET);
2567 RES_SET_H_ERRNO(res, NETDB_INTERNAL);
2571 for (t = target; t; t = t->next) {
2576 hp = (HEADER *)(void *)t->answer;
2578 /* make it easier... */
2584 oflags = res->_flags;
2587 hp->rcode = NOERROR; /* default */
2590 if (res->options & RES_DEBUG)
2591 printf(";; res_query(%s, %d, %d)\n", name, class, type);
2594 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL,
2596 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 &&
2597 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U)
2598 n = res_nopt(res, n, buf, MAXPACKET, anslen);
2601 if (res->options & RES_DEBUG)
2602 printf(";; res_query: mkquery failed\n");
2605 RES_SET_H_ERRNO(res, NO_RECOVERY);
2608 n = res_nsend(res, buf, n, answer, anslen);
2611 * if the query choked with EDNS0, retry
2614 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC))
2616 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) {
2617 res->_flags |= RES_F_EDNS0ERR;
2618 if (res->options & RES_DEBUG)
2619 printf(";; res_nquery: retry without EDNS0\n");
2622 rcode = hp->rcode; /* record most recent error */
2624 if (res->options & RES_DEBUG)
2625 printf(";; res_query: send error\n");
2631 hp->rcode = FORMERR; /* XXX not very informative */
2632 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
2633 rcode = hp->rcode; /* record most recent error */
2635 if (res->options & RES_DEBUG)
2636 printf(";; rcode = %u, ancount=%u\n", hp->rcode,
2637 ntohs(hp->ancount));
2642 ancount += ntohs(hp->ancount);
2652 RES_SET_H_ERRNO(res, HOST_NOT_FOUND);
2655 RES_SET_H_ERRNO(res, TRY_AGAIN);
2658 RES_SET_H_ERRNO(res, NO_DATA);
2664 RES_SET_H_ERRNO(res, NO_RECOVERY);
2673 * Formulate a normal query, send, and retrieve answer in supplied buffer.
2674 * Return the size of the response on success, -1 on error.
2675 * If enabled, implement search rules until answer or unrecoverable failure
2676 * is detected. Error code, if any, is left in h_errno.
2679 res_searchN(const char *name, struct res_target *target, res_state res)
2681 const char *cp, * const *domain;
2682 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/
2684 int trailing_dot, ret, saved_herrno;
2685 int got_nodata = 0, got_servfail = 0, root_on_list = 0;
2686 int tried_as_is = 0;
2688 char abuf[MAXDNAME];
2691 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */
2693 for (cp = name; *cp; cp++)
2694 dots += (*cp == '.');
2696 if (cp > name && *--cp == '.')
2700 * if there aren't any dots, it could be a user-level alias
2703 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL)
2704 return (res_queryN(cp, target, res));
2707 * If there are enough dots in the name, let's just give it a
2708 * try 'as is'. The threshold can be set with the "ndots" option.
2709 * Also, query 'as is', if there is a trailing dot in the name.
2712 if (dots >= res->ndots || trailing_dot) {
2713 ret = res_querydomainN(name, NULL, target, res);
2714 if (ret > 0 || trailing_dot)
2716 if (errno == ECONNREFUSED) {
2717 RES_SET_H_ERRNO(res, TRY_AGAIN);
2720 switch (res->res_h_errno) {
2722 case HOST_NOT_FOUND:
2725 if (hp->rcode == SERVFAIL)
2731 saved_herrno = res->res_h_errno;
2736 * We do at least one level of search if
2737 * - there is no dot and RES_DEFNAME is set, or
2738 * - there is at least one dot, there is no trailing dot,
2739 * and RES_DNSRCH is set.
2741 if ((!dots && (res->options & RES_DEFNAMES)) ||
2742 (dots && !trailing_dot && (res->options & RES_DNSRCH))) {
2745 for (domain = (const char * const *)res->dnsrch;
2750 if (domain[0][0] == '\0' ||
2751 (domain[0][0] == '.' && domain[0][1] == '\0'))
2754 if (root_on_list && tried_as_is)
2757 ret = res_querydomainN(name, *domain, target, res);
2762 * If no server present, give up.
2763 * If name isn't found in this domain,
2764 * keep trying higher domains in the search list
2765 * (if that's enabled).
2766 * On a NO_DATA error, keep trying, otherwise
2767 * a wildcard entry of another type could keep us
2768 * from finding this entry higher in the domain.
2769 * If we get some other error (negative answer or
2770 * server failure), then stop searching up,
2771 * but try the input name below in case it's
2774 if (errno == ECONNREFUSED) {
2775 RES_SET_H_ERRNO(res, TRY_AGAIN);
2779 switch (res->res_h_errno) {
2783 case HOST_NOT_FOUND:
2788 if (hp->rcode == SERVFAIL) {
2789 /* try next search element, if any */
2794 /* anything else implies that we're done */
2798 * if we got here for some reason other than DNSRCH,
2799 * we only wanted one iteration of the loop, so stop.
2801 if (!(res->options & RES_DNSRCH))
2806 switch (res->res_h_errno) {
2808 case HOST_NOT_FOUND:
2811 if (hp->rcode == SERVFAIL)
2819 * If the query has not already been tried as is then try it
2820 * unless RES_NOTLDQUERY is set and there were no dots.
2822 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) &&
2823 !(tried_as_is || root_on_list)) {
2824 ret = res_querydomainN(name, NULL, target, res);
2830 * if we got here, we didn't satisfy the search.
2831 * if we did an initial full query, return that query's h_errno
2832 * (note that we wouldn't be here if that query had succeeded).
2833 * else if we ever got a nodata, send that back as the reason.
2834 * else send back meaningless h_errno, that being the one from
2835 * the last DNSRCH we did.
2838 if (saved_herrno != -1)
2839 RES_SET_H_ERRNO(res, saved_herrno);
2840 else if (got_nodata)
2841 RES_SET_H_ERRNO(res, NO_DATA);
2842 else if (got_servfail)
2843 RES_SET_H_ERRNO(res, TRY_AGAIN);
2848 * Perform a call on res_query on the concatenation of name and domain,
2849 * removing a trailing dot from name if domain is NULL.
2852 res_querydomainN(const char *name, const char *domain,
2853 struct res_target *target, res_state res)
2855 char nbuf[MAXDNAME];
2856 const char *longname = nbuf;
2860 if (res->options & RES_DEBUG)
2861 printf(";; res_querydomain(%s, %s)\n",
2862 name, domain?domain:"<Nil>");
2864 if (domain == NULL) {
2866 * Check for trailing '.';
2867 * copy without '.' if present.
2870 if (n >= MAXDNAME) {
2871 RES_SET_H_ERRNO(res, NO_RECOVERY);
2874 if (n > 0 && name[--n] == '.') {
2875 strncpy(nbuf, name, n);
2882 if (n + d + 1 >= MAXDNAME) {
2883 RES_SET_H_ERRNO(res, NO_RECOVERY);
2886 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain);
2888 return (res_queryN(longname, target, res));