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 <sys/queue.h>
67 #include <net/if_var.h>
68 #include <sys/sysctl.h>
69 #include <sys/ioctl.h>
70 #include <netinet6/in6_var.h> /* XXX */
72 #include <arpa/inet.h>
73 #include <arpa/nameser.h>
75 #include <rpcsvc/yp_prot.h>
76 #include <rpcsvc/ypclnt.h>
87 #include "res_config.h"
95 #include "un-namespace.h"
96 #include "libc_private.h"
101 #if defined(__KAME__) && defined(INET6)
109 static const char in_addrany[] = { 0, 0, 0, 0 };
110 static const char in_loopback[] = { 127, 0, 0, 1 };
112 static const char in6_addrany[] = {
113 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
115 static const char in6_loopback[] = {
116 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
121 TAILQ_ENTRY(policyqueue) pc_entry;
123 struct in6_addrpolicy pc_policy;
126 TAILQ_HEAD(policyhead, policyqueue);
128 static const struct afd {
133 const char *a_addrany;
134 const char *a_loopback;
139 {PF_INET6, sizeof(struct in6_addr),
140 sizeof(struct sockaddr_in6),
141 offsetof(struct sockaddr_in6, sin6_addr),
142 in6_addrany, in6_loopback, 1},
147 {PF_INET, sizeof(struct in_addr),
148 sizeof(struct sockaddr_in),
149 offsetof(struct sockaddr_in, sin_addr),
150 in_addrany, in_loopback, 0},
151 {0, 0, 0, 0, NULL, NULL, 0},
159 #define WILD_AF(ex) ((ex)->e_wild & 0x01)
160 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02)
161 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04)
164 static const struct explore explore[] = {
166 { PF_LOCAL, ANY, ANY, 0x01 },
169 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, 0x07 },
170 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, 0x07 },
171 { PF_INET6, SOCK_STREAM, IPPROTO_SCTP, 0x03 },
172 { PF_INET6, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 },
173 { PF_INET6, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 },
174 { PF_INET6, SOCK_RAW, ANY, 0x05 },
176 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, 0x07 },
177 { PF_INET, SOCK_STREAM, IPPROTO_TCP, 0x07 },
178 { PF_INET, SOCK_STREAM, IPPROTO_SCTP, 0x03 },
179 { PF_INET, SOCK_SEQPACKET, IPPROTO_SCTP, 0x07 },
180 { PF_INET, SOCK_DGRAM, IPPROTO_UDPLITE, 0x03 },
181 { PF_INET, SOCK_RAW, ANY, 0x05 },
191 #define AIO_SRCFLAG_DEPRECATED 0x1
195 struct sockaddr_storage aiou_ss;
196 struct sockaddr aiou_sa;
198 #define aio_srcsa aio_src_un.aiou_sa
199 u_int32_t aio_srcflag;
202 struct policyqueue *aio_srcpolicy;
203 struct policyqueue *aio_dstpolicy;
204 struct addrinfo *aio_ai;
208 static const ns_src default_dns_files[] = {
209 { NSSRC_FILES, NS_SUCCESS },
210 { NSSRC_DNS, NS_SUCCESS },
215 struct res_target *next;
216 const char *name; /* domain name */
217 int qclass, qtype; /* class and type of query */
218 u_char *answer; /* buffer to put answer */
219 int anslen; /* size of answer buffer */
220 int n; /* result length */
223 #define MAXPACKET (64*1024)
227 u_char buf[MAXPACKET];
230 static int str2number(const char *, int *);
231 static int explore_copy(const struct addrinfo *, const struct addrinfo *,
233 static int explore_null(const struct addrinfo *,
234 const char *, struct addrinfo **);
235 static int explore_numeric(const struct addrinfo *, const char *,
236 const char *, struct addrinfo **, const char *);
237 static int explore_numeric_scope(const struct addrinfo *, const char *,
238 const char *, struct addrinfo **);
239 static int get_canonname(const struct addrinfo *,
240 struct addrinfo *, const char *);
241 static struct addrinfo *get_ai(const struct addrinfo *,
242 const struct afd *, const char *);
243 static struct addrinfo *copy_ai(const struct addrinfo *);
244 static int get_portmatch(const struct addrinfo *, const char *);
245 static int get_port(struct addrinfo *, const char *, int);
246 static const struct afd *find_afd(int);
247 static int addrconfig(struct addrinfo *);
248 static void set_source(struct ai_order *, struct policyhead *);
249 static int comp_dst(const void *, const void *);
251 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *);
253 static int gai_addr2scopetype(struct sockaddr *);
255 static int explore_fqdn(const struct addrinfo *, const char *,
256 const char *, struct addrinfo **);
258 static int reorder(struct addrinfo *);
259 static int get_addrselectpolicy(struct policyhead *);
260 static void free_addrselectpolicy(struct policyhead *);
261 static struct policyqueue *match_addrselectpolicy(struct sockaddr *,
262 struct policyhead *);
263 static int matchlen(struct sockaddr *, struct sockaddr *);
265 static struct addrinfo *getanswer(const querybuf *, int, const char *, int,
266 const struct addrinfo *, res_state);
267 #if defined(RESOLVSORT)
268 static int addr4sort(struct addrinfo *, res_state);
270 static int _dns_getaddrinfo(void *, void *, va_list);
271 static void _sethtent(FILE **);
272 static void _endhtent(FILE **);
273 static struct addrinfo *_gethtent(FILE **, const char *,
274 const struct addrinfo *);
275 static int _files_getaddrinfo(void *, void *, va_list);
277 static struct addrinfo *_yphostent(char *, const struct addrinfo *);
278 static int _yp_getaddrinfo(void *, void *, va_list);
281 static int addrinfo_id_func(char *, size_t *, va_list, void *);
282 static int addrinfo_marshal_func(char *, size_t *, void *, va_list, void *);
283 static int addrinfo_unmarshal_func(char *, size_t, void *, va_list, void *);
286 static int res_queryN(const char *, struct res_target *, res_state);
287 static int res_searchN(const char *, struct res_target *, res_state);
288 static int res_querydomainN(const char *, const char *,
289 struct res_target *, res_state);
291 /* XXX macros that make external reference is BAD. */
293 #define GET_AI(ai, afd, addr) \
295 /* external reference: pai, error, and label free */ \
296 (ai) = get_ai(pai, (afd), (addr)); \
297 if ((ai) == NULL) { \
298 error = EAI_MEMORY; \
301 } while (/*CONSTCOND*/0)
303 #define GET_PORT(ai, serv) \
305 /* external reference: error and label free */ \
306 error = get_port((ai), (serv), 0); \
309 } while (/*CONSTCOND*/0)
311 #define GET_CANONNAME(ai, str) \
313 /* external reference: pai, error and label free */ \
314 error = get_canonname(pai, (ai), (str)); \
317 } while (/*CONSTCOND*/0)
321 /* external reference: error, and label bad */ \
325 } while (/*CONSTCOND*/0)
327 #define MATCH_FAMILY(x, y, w) \
328 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
329 #define MATCH(x, y, w) \
330 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
333 freeaddrinfo(struct addrinfo *ai)
335 struct addrinfo *next;
339 if (ai->ai_canonname)
340 free(ai->ai_canonname);
341 /* no need to free(ai->ai_addr) */
348 str2number(const char *p, int *portp)
357 v = strtoul(p, &ep, 10);
358 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) {
366 getaddrinfo(const char *hostname, const char *servname,
367 const struct addrinfo *hints, struct addrinfo **res)
369 struct addrinfo sentinel;
370 struct addrinfo *cur;
372 struct addrinfo ai, ai0, *afai;
373 struct addrinfo *pai;
374 const struct afd *afd;
375 const struct explore *ex;
376 struct addrinfo *afailist[sizeof(afdl)/sizeof(afdl[0])];
377 struct addrinfo *afai_unspec;
381 /* ensure we return NULL on errors */
384 memset(&ai, 0, sizeof(ai));
386 memset(afailist, 0, sizeof(afailist));
389 memset(&sentinel, 0, sizeof(sentinel));
393 pai->ai_family = PF_UNSPEC;
394 pai->ai_socktype = ANY;
395 pai->ai_protocol = ANY;
397 pai->ai_canonname = NULL;
401 if (hostname == NULL && servname == NULL)
404 /* error check for hints */
405 if (hints->ai_addrlen || hints->ai_canonname ||
406 hints->ai_addr || hints->ai_next)
407 ERR(EAI_BADHINTS); /* xxx */
408 if (hints->ai_flags & ~AI_MASK)
410 switch (hints->ai_family) {
420 memcpy(pai, hints, sizeof(*pai));
423 * if both socktype/protocol are specified, check if they
424 * are meaningful combination.
426 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
427 for (ex = explore; ex->e_af >= 0; ex++) {
428 if (!MATCH_FAMILY(pai->ai_family, ex->e_af,
431 if (!MATCH(pai->ai_socktype, ex->e_socktype,
434 if (!MATCH(pai->ai_protocol, ex->e_protocol,
448 * check for special cases. (1) numeric servname is disallowed if
449 * socktype/protocol are left unspecified. (2) servname is disallowed
450 * for raw and other inet{,6} sockets.
452 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
454 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
457 ai0 = *pai; /* backup *pai */
459 if (pai->ai_family == PF_UNSPEC) {
461 pai->ai_family = PF_INET6;
463 pai->ai_family = PF_INET;
466 error = get_portmatch(pai, servname);
476 * NULL hostname, or numeric hostname.
477 * If numeric representation of AF1 can be interpreted as FQDN
478 * representation of AF2, we need to think again about the code below.
481 for (afd = afdl; afd->a_af; afd++) {
484 if (!MATCH_FAMILY(pai->ai_family, afd->a_af, 1))
487 if (pai->ai_family == PF_UNSPEC)
488 pai->ai_family = afd->a_af;
490 if (hostname == NULL) {
491 error = explore_null(pai, servname,
492 &afailist[afd - afdl]);
495 * Errors from explore_null should be unexpected and
496 * be caught to avoid returning an incomplete result.
501 error = explore_numeric_scope(pai, hostname, servname,
502 &afailist[afd - afdl]);
505 * explore_numeric_scope returns an error for address
506 * families that do not match that of hostname.
507 * Thus we should not catch the error at this moment.
511 if (!error && afailist[afd - afdl])
519 if (hostname == NULL)
520 ERR(EAI_NONAME); /* used to be EAI_NODATA */
521 if (pai->ai_flags & AI_NUMERICHOST)
524 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0))
528 * hostname as alphabetical name.
531 error = explore_fqdn(pai, hostname, servname, &afai_unspec);
534 for (ex = explore; ex->e_af >= 0; ex++) {
537 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
539 if (!MATCH(pai->ai_socktype, ex->e_socktype,
542 if (!MATCH(pai->ai_protocol, ex->e_protocol,
546 if (pai->ai_family == PF_UNSPEC)
547 pai->ai_family = ex->e_af;
548 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
549 pai->ai_socktype = ex->e_socktype;
550 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
551 pai->ai_protocol = ex->e_protocol;
554 * if the servname does not match socktype/protocol, ignore it.
556 if (get_portmatch(pai, servname) != 0)
562 if ((afd = find_afd(pai->ai_family)) == NULL)
564 /* XXX assumes that afd points inside afdl[] */
565 afai = afailist[afd - afdl];
570 error = explore_copy(pai, afai, &cur->ai_next);
574 while (cur && cur->ai_next)
579 * ensure we return either:
580 * - error == 0, non-NULL *res
581 * - error != 0, NULL *res
584 if (sentinel.ai_next) {
586 * If the returned entry is for an active connection,
587 * and the given name is not numeric, reorder the
588 * list, so that the application would try the list
589 * in the most efficient order. Since the head entry
590 * of the original list may contain ai_canonname and
591 * that entry may be moved elsewhere in the new list,
592 * we keep the pointer and will restore it in the new
593 * head entry. (Note that RFC3493 requires the head
594 * entry store it when requested by the caller).
596 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) {
601 sentinel.ai_next->ai_canonname;
602 sentinel.ai_next->ai_canonname = NULL;
603 (void)reorder(&sentinel);
604 if (sentinel.ai_next->ai_canonname ==
606 sentinel.ai_next->ai_canonname
608 } else if (canonname != NULL)
612 *res = sentinel.ai_next;
619 freeaddrinfo(afai_unspec);
620 for (afd = afdl; afd->a_af; afd++) {
621 if (afailist[afd - afdl])
622 freeaddrinfo(afailist[afd - afdl]);
625 if (sentinel.ai_next)
626 freeaddrinfo(sentinel.ai_next);
632 reorder(struct addrinfo *sentinel)
634 struct addrinfo *ai, **aip;
635 struct ai_order *aio;
637 struct policyhead policyhead;
639 /* count the number of addrinfo elements for sorting. */
640 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++)
644 * If the number is small enough, we can skip the reordering process.
649 /* allocate a temporary array for sort and initialization of it. */
650 if ((aio = malloc(sizeof(*aio) * n)) == NULL)
651 return(n); /* give up reordering */
652 memset(aio, 0, sizeof(*aio) * n);
654 /* retrieve address selection policy from the kernel */
655 TAILQ_INIT(&policyhead);
656 if (!get_addrselectpolicy(&policyhead)) {
657 /* no policy is installed into kernel, we don't sort. */
662 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) {
664 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr);
665 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr,
667 set_source(&aio[i], &policyhead);
670 /* perform sorting. */
671 qsort(aio, n, sizeof(*aio), comp_dst);
673 /* reorder the addrinfo chain. */
674 for (i = 0, aip = &sentinel->ai_next; i < n; i++) {
675 *aip = aio[i].aio_ai;
676 aip = &aio[i].aio_ai->ai_next;
680 /* cleanup and return */
682 free_addrselectpolicy(&policyhead);
687 get_addrselectpolicy(struct policyhead *head)
690 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY };
693 struct in6_addrpolicy *pol, *ep;
695 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), NULL, &l, NULL, 0) < 0)
699 if ((buf = malloc(l)) == NULL)
701 if (sysctl(mib, sizeof(mib) / sizeof(mib[0]), buf, &l, NULL, 0) < 0) {
706 ep = (struct in6_addrpolicy *)(buf + l);
707 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) {
708 struct policyqueue *new;
710 if ((new = malloc(sizeof(*new))) == NULL) {
711 free_addrselectpolicy(head); /* make the list empty */
714 new->pc_policy = *pol;
715 TAILQ_INSERT_TAIL(head, new, pc_entry);
726 free_addrselectpolicy(struct policyhead *head)
728 struct policyqueue *ent, *nent;
730 for (ent = TAILQ_FIRST(head); ent; ent = nent) {
731 nent = TAILQ_NEXT(ent, pc_entry);
732 TAILQ_REMOVE(head, ent, pc_entry);
737 static struct policyqueue *
738 match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head)
741 struct policyqueue *ent, *bestent = NULL;
742 struct in6_addrpolicy *pol;
743 int matchlen, bestmatchlen = -1;
744 u_char *mp, *ep, *k, *p, m;
745 struct sockaddr_in6 key;
747 switch(addr->sa_family) {
749 key = *(struct sockaddr_in6 *)addr;
752 /* convert the address into IPv4-mapped IPv6 address. */
753 memset(&key, 0, sizeof(key));
754 key.sin6_family = AF_INET6;
755 key.sin6_len = sizeof(key);
756 key.sin6_addr.s6_addr[10] = 0xff;
757 key.sin6_addr.s6_addr[11] = 0xff;
758 memcpy(&key.sin6_addr.s6_addr[12],
759 &((struct sockaddr_in *)addr)->sin_addr, 4);
765 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) {
766 pol = &ent->pc_policy;
769 mp = (u_char *)&pol->addrmask.sin6_addr;
770 ep = mp + 16; /* XXX: scope field? */
771 k = (u_char *)&key.sin6_addr;
772 p = (u_char *)&pol->addr.sin6_addr;
773 for (; mp < ep && *mp; mp++, k++, p++) {
776 goto next; /* not match */
777 if (m == 0xff) /* short cut for a typical case */
787 /* matched. check if this is better than the current best. */
788 if (matchlen > bestmatchlen) {
790 bestmatchlen = matchlen;
805 set_source(struct ai_order *aio, struct policyhead *ph)
807 struct addrinfo ai = *aio->aio_ai;
808 struct sockaddr_storage ss;
812 /* set unspec ("no source is available"), just in case */
813 aio->aio_srcsa.sa_family = AF_UNSPEC;
814 aio->aio_srcscope = -1;
816 switch(ai.ai_family) {
822 default: /* ignore unsupported AFs explicitly */
826 /* XXX: make a dummy addrinfo to call connect() */
827 ai.ai_socktype = SOCK_DGRAM;
828 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */
830 memset(&ss, 0, sizeof(ss));
831 memcpy(&ss, ai.ai_addr, ai.ai_addrlen);
832 ai.ai_addr = (struct sockaddr *)&ss;
833 get_port(&ai, "1", 0);
835 /* open a socket to get the source address for the given dst */
836 if ((s = _socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC,
837 ai.ai_protocol)) < 0)
838 return; /* give up */
839 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0)
841 srclen = ai.ai_addrlen;
842 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) {
843 aio->aio_srcsa.sa_family = AF_UNSPEC;
846 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa);
847 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph);
848 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr);
850 if (ai.ai_family == AF_INET6) {
851 struct in6_ifreq ifr6;
854 memset(&ifr6, 0, sizeof(ifr6));
855 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen);
856 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) {
857 flags6 = ifr6.ifr_ifru.ifru_flags6;
858 if ((flags6 & IN6_IFF_DEPRECATED))
859 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED;
870 matchlen(struct sockaddr *src, struct sockaddr *dst)
877 switch (src->sa_family) {
880 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr;
881 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr;
882 addrlen = sizeof(struct in6_addr);
887 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr;
888 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr;
889 addrlen = sizeof(struct in_addr);
897 if ((r = (*d++ ^ *s++)) != 0) {
898 while (r < addrlen * 8) {
909 comp_dst(const void *arg1, const void *arg2)
911 const struct ai_order *dst1 = arg1, *dst2 = arg2;
914 * Rule 1: Avoid unusable destinations.
915 * XXX: we currently do not consider if an appropriate route exists.
917 if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
918 dst2->aio_srcsa.sa_family == AF_UNSPEC) {
921 if (dst1->aio_srcsa.sa_family == AF_UNSPEC &&
922 dst2->aio_srcsa.sa_family != AF_UNSPEC) {
926 /* Rule 2: Prefer matching scope. */
927 if (dst1->aio_dstscope == dst1->aio_srcscope &&
928 dst2->aio_dstscope != dst2->aio_srcscope) {
931 if (dst1->aio_dstscope != dst1->aio_srcscope &&
932 dst2->aio_dstscope == dst2->aio_srcscope) {
936 /* Rule 3: Avoid deprecated addresses. */
937 if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
938 dst2->aio_srcsa.sa_family != AF_UNSPEC) {
939 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
940 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
943 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
944 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
949 /* Rule 4: Prefer home addresses. */
950 /* XXX: not implemented yet */
952 /* Rule 5: Prefer matching label. */
954 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy &&
955 dst1->aio_srcpolicy->pc_policy.label ==
956 dst1->aio_dstpolicy->pc_policy.label &&
957 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL ||
958 dst2->aio_srcpolicy->pc_policy.label !=
959 dst2->aio_dstpolicy->pc_policy.label)) {
962 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy &&
963 dst2->aio_srcpolicy->pc_policy.label ==
964 dst2->aio_dstpolicy->pc_policy.label &&
965 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL ||
966 dst1->aio_srcpolicy->pc_policy.label !=
967 dst1->aio_dstpolicy->pc_policy.label)) {
972 /* Rule 6: Prefer higher precedence. */
974 if (dst1->aio_dstpolicy &&
975 (dst2->aio_dstpolicy == NULL ||
976 dst1->aio_dstpolicy->pc_policy.preced >
977 dst2->aio_dstpolicy->pc_policy.preced)) {
980 if (dst2->aio_dstpolicy &&
981 (dst1->aio_dstpolicy == NULL ||
982 dst2->aio_dstpolicy->pc_policy.preced >
983 dst1->aio_dstpolicy->pc_policy.preced)) {
988 /* Rule 7: Prefer native transport. */
989 /* XXX: not implemented yet */
991 /* Rule 8: Prefer smaller scope. */
992 if (dst1->aio_dstscope >= 0 &&
993 dst1->aio_dstscope < dst2->aio_dstscope) {
996 if (dst2->aio_dstscope >= 0 &&
997 dst2->aio_dstscope < dst1->aio_dstscope) {
1002 * Rule 9: Use longest matching prefix.
1003 * We compare the match length in a same AF only.
1005 if (dst1->aio_ai->ai_addr->sa_family ==
1006 dst2->aio_ai->ai_addr->sa_family) {
1007 if (dst1->aio_matchlen > dst2->aio_matchlen) {
1010 if (dst1->aio_matchlen < dst2->aio_matchlen) {
1015 /* Rule 10: Otherwise, leave the order unchanged. */
1020 * Copy from scope.c.
1021 * XXX: we should standardize the functions and link them as standard
1025 gai_addr2scopetype(struct sockaddr *sa)
1028 struct sockaddr_in6 *sa6;
1030 struct sockaddr_in *sa4;
1032 switch(sa->sa_family) {
1035 sa6 = (struct sockaddr_in6 *)sa;
1036 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
1037 /* just use the scope field of the multicast address */
1038 return(sa6->sin6_addr.s6_addr[2] & 0x0f);
1041 * Unicast addresses: map scope type to corresponding scope
1042 * value defined for multcast addresses.
1043 * XXX: hardcoded scope type values are bad...
1045 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr))
1046 return(1); /* node local scope */
1047 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr))
1048 return(2); /* link-local scope */
1049 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr))
1050 return(5); /* site-local scope */
1051 return(14); /* global scope */
1056 * IPv4 pseudo scoping according to RFC 3484.
1058 sa4 = (struct sockaddr_in *)sa;
1059 /* IPv4 autoconfiguration addresses have link-local scope. */
1060 if (((u_char *)&sa4->sin_addr)[0] == 169 &&
1061 ((u_char *)&sa4->sin_addr)[1] == 254)
1063 /* Private addresses have site-local scope. */
1064 if (((u_char *)&sa4->sin_addr)[0] == 10 ||
1065 (((u_char *)&sa4->sin_addr)[0] == 172 &&
1066 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) ||
1067 (((u_char *)&sa4->sin_addr)[0] == 192 &&
1068 ((u_char *)&sa4->sin_addr)[1] == 168))
1069 return(14); /* XXX: It should be 5 unless NAT */
1070 /* Loopback addresses have link-local scope. */
1071 if (((u_char *)&sa4->sin_addr)[0] == 127)
1076 errno = EAFNOSUPPORT; /* is this a good error? */
1082 explore_copy(const struct addrinfo *pai, const struct addrinfo *src0,
1083 struct addrinfo **res)
1086 struct addrinfo sentinel, *cur;
1087 const struct addrinfo *src;
1090 sentinel.ai_next = NULL;
1093 for (src = src0; src != NULL; src = src->ai_next) {
1094 if (src->ai_family != pai->ai_family)
1097 cur->ai_next = copy_ai(src);
1098 if (!cur->ai_next) {
1103 cur->ai_next->ai_socktype = pai->ai_socktype;
1104 cur->ai_next->ai_protocol = pai->ai_protocol;
1108 *res = sentinel.ai_next;
1112 freeaddrinfo(sentinel.ai_next);
1118 * passive socket -> anyaddr (0.0.0.0 or ::)
1119 * non-passive socket -> localhost (127.0.0.1 or ::1)
1122 explore_null(const struct addrinfo *pai, const char *servname,
1123 struct addrinfo **res)
1126 const struct afd *afd;
1127 struct addrinfo *ai;
1134 * filter out AFs that are not supported by the kernel
1137 s = _socket(pai->ai_family, SOCK_DGRAM | SOCK_CLOEXEC, 0);
1139 if (errno != EMFILE)
1144 afd = find_afd(pai->ai_family);
1148 if (pai->ai_flags & AI_PASSIVE) {
1149 GET_AI(ai, afd, afd->a_addrany);
1150 GET_PORT(ai, servname);
1152 GET_AI(ai, afd, afd->a_loopback);
1153 GET_PORT(ai, servname);
1169 explore_numeric(const struct addrinfo *pai, const char *hostname,
1170 const char *servname, struct addrinfo **res, const char *canonname)
1172 const struct afd *afd;
1173 struct addrinfo *ai;
1175 char pton[PTON_MAX];
1180 afd = find_afd(pai->ai_family);
1184 switch (afd->a_af) {
1187 * RFC3493 requires getaddrinfo() to accept AF_INET formats
1188 * that are accepted by inet_addr() and its family. The
1189 * accepted forms includes the "classful" one, which inet_pton
1190 * does not accept. So we need to separate the case for
1193 if (inet_aton(hostname, (struct in_addr *)pton) != 1)
1197 if (inet_pton(afd->a_af, hostname, pton) != 1)
1202 if (pai->ai_family == afd->a_af) {
1203 GET_AI(ai, afd, pton);
1204 GET_PORT(ai, servname);
1205 if ((pai->ai_flags & AI_CANONNAME)) {
1207 * Set the numeric address itself as the canonical
1208 * name, based on a clarification in RFC3493.
1210 GET_CANONNAME(ai, canonname);
1214 * XXX: This should not happen since we already matched the AF
1231 * numeric hostname with scope
1234 explore_numeric_scope(const struct addrinfo *pai, const char *hostname,
1235 const char *servname, struct addrinfo **res)
1237 #if !defined(SCOPE_DELIMITER) || !defined(INET6)
1238 return explore_numeric(pai, hostname, servname, res, hostname);
1240 const struct afd *afd;
1241 struct addrinfo *cur;
1243 char *cp, *hostname2 = NULL, *scope, *addr;
1244 struct sockaddr_in6 *sin6;
1246 afd = find_afd(pai->ai_family);
1251 return explore_numeric(pai, hostname, servname, res, hostname);
1253 cp = strchr(hostname, SCOPE_DELIMITER);
1255 return explore_numeric(pai, hostname, servname, res, hostname);
1258 * Handle special case of <scoped_address><delimiter><scope id>
1260 hostname2 = strdup(hostname);
1261 if (hostname2 == NULL)
1263 /* terminate at the delimiter */
1264 hostname2[cp - hostname] = '\0';
1268 error = explore_numeric(pai, addr, servname, res, hostname);
1272 for (cur = *res; cur; cur = cur->ai_next) {
1273 if (cur->ai_family != AF_INET6)
1275 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
1276 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) {
1280 return(EAI_NONAME); /* XXX: is return OK? */
1282 sin6->sin6_scope_id = scopeid;
1288 if (error && *res) {
1297 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str)
1299 if ((pai->ai_flags & AI_CANONNAME) != 0) {
1300 ai->ai_canonname = strdup(str);
1301 if (ai->ai_canonname == NULL)
1307 static struct addrinfo *
1308 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr)
1311 struct addrinfo *ai;
1313 struct in6_addr faith_prefix;
1320 * Transfrom an IPv4 addr into a special IPv6 addr format for
1321 * IPv6->IPv4 translation gateway. (only TCP is supported now)
1323 * +-----------------------------------+------------+
1324 * | faith prefix part (12 bytes) | embedded |
1325 * | | IPv4 addr part (4 bytes)
1326 * +-----------------------------------+------------+
1328 * faith prefix part is specified as ascii IPv6 addr format
1329 * in environmental variable GAI.
1330 * For FAITH to work correctly, routing to faith prefix must be
1331 * setup toward a machine where a FAITH daemon operates.
1332 * Also, the machine must enable some mechanizm
1333 * (e.g. faith interface hack) to divert those packet with
1334 * faith prefixed destination addr to user-land FAITH daemon.
1336 fp_str = getenv("GAI");
1337 if (fp_str && inet_pton(AF_INET6, fp_str, &faith_prefix) == 1 &&
1338 afd->a_af == AF_INET && pai->ai_socktype == SOCK_STREAM) {
1342 memcpy(&v4a, addr, sizeof v4a);
1343 v4a_top = v4a >> IN_CLASSA_NSHIFT;
1344 if (!IN_MULTICAST(v4a) && !IN_EXPERIMENTAL(v4a) &&
1345 v4a_top != 0 && v4a != IN_LOOPBACKNET) {
1346 afd = &afdl[N_INET6];
1347 memcpy(&faith_prefix.s6_addr[12], addr,
1348 sizeof(struct in_addr));
1354 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo)
1355 + (afd->a_socklen));
1359 memcpy(ai, pai, sizeof(struct addrinfo));
1360 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
1361 memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
1362 ai->ai_addr->sa_len = afd->a_socklen;
1363 ai->ai_addrlen = afd->a_socklen;
1364 ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
1365 p = (char *)(void *)(ai->ai_addr);
1368 memcpy(p + afd->a_off, &faith_prefix, (size_t)afd->a_addrlen);
1371 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen);
1375 /* XXX need to malloc() the same way we do from other functions! */
1376 static struct addrinfo *
1377 copy_ai(const struct addrinfo *pai)
1379 struct addrinfo *ai;
1382 l = sizeof(*ai) + pai->ai_addrlen;
1383 if ((ai = (struct addrinfo *)malloc(l)) == NULL)
1386 memcpy(ai, pai, sizeof(*ai));
1387 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
1388 memcpy(ai->ai_addr, pai->ai_addr, pai->ai_addrlen);
1390 if (pai->ai_canonname) {
1391 l = strlen(pai->ai_canonname) + 1;
1392 if ((ai->ai_canonname = malloc(l)) == NULL) {
1396 strlcpy(ai->ai_canonname, pai->ai_canonname, l);
1398 /* just to make sure */
1399 ai->ai_canonname = NULL;
1408 get_portmatch(const struct addrinfo *ai, const char *servname)
1411 /* get_port does not touch first argument when matchonly == 1. */
1412 /* LINTED const cast */
1413 return get_port((struct addrinfo *)ai, servname, 1);
1417 get_port(struct addrinfo *ai, const char *servname, int matchonly)
1424 if (servname == NULL)
1426 switch (ai->ai_family) {
1436 switch (ai->ai_socktype) {
1441 case SOCK_SEQPACKET:
1445 switch (ai->ai_family) {
1458 return EAI_SOCKTYPE;
1461 error = str2number(servname, &port);
1465 if (port < 0 || port > 65535)
1469 if (ai->ai_flags & AI_NUMERICSERV)
1472 switch (ai->ai_protocol) {
1482 case IPPROTO_UDPLITE:
1490 if ((sp = getservbyname(servname, proto)) == NULL)
1496 switch (ai->ai_family) {
1498 ((struct sockaddr_in *)(void *)
1499 ai->ai_addr)->sin_port = port;
1503 ((struct sockaddr_in6 *)(void *)
1504 ai->ai_addr)->sin6_port = port;
1513 static const struct afd *
1516 const struct afd *afd;
1518 if (af == PF_UNSPEC)
1520 for (afd = afdl; afd->a_af; afd++) {
1521 if (afd->a_af == af)
1528 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend
1529 * will take care of it.
1530 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure
1531 * if the code is right or not.
1533 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with
1537 addrconfig(struct addrinfo *pai)
1543 * Note that implementation dependent test for address
1544 * configuration should be done everytime called
1545 * (or apropriate interval),
1546 * because addresses will be dynamically assigned or deleted.
1548 af = pai->ai_family;
1549 if (af == AF_UNSPEC) {
1550 if ((s = _socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC, 0)) < 0)
1554 if ((s = _socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC,
1561 if (af != AF_UNSPEC) {
1562 if ((s = _socket(af, SOCK_DGRAM | SOCK_CLOEXEC, 0)) < 0)
1566 pai->ai_family = af;
1571 /* convert a string to a scope identifier. XXX: IPv6 specific */
1573 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid)
1576 struct in6_addr *a6;
1579 a6 = &sin6->sin6_addr;
1581 /* empty scopeid portion is invalid */
1585 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6) ||
1586 IN6_IS_ADDR_MC_NODELOCAL(a6)) {
1588 * We currently assume a one-to-one mapping between links
1589 * and interfaces, so we simply use interface indices for
1590 * like-local scopes.
1592 *scopeid = if_nametoindex(scope);
1598 /* still unclear about literal, allow numeric only - placeholder */
1599 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
1601 if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
1604 goto trynumeric; /* global */
1606 /* try to convert to a numeric id as a last resort */
1609 lscopeid = strtoul(scope, &ep, 10);
1610 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL);
1611 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid)
1621 addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap,
1627 const int op_id = 0; /* identifies the getaddrinfo for the cache */
1629 struct addrinfo *hints;
1632 int ai_flags, ai_family, ai_socktype, ai_protocol;
1633 size_t desired_size, size;
1635 statp = __res_state();
1636 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES |
1637 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6);
1639 hostname = va_arg(ap, char *);
1640 hints = va_arg(ap, struct addrinfo *);
1642 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4;
1643 if (hostname != NULL) {
1644 size = strlen(hostname);
1645 desired_size += size + 1;
1649 if (desired_size > *buffer_size) {
1650 *buffer_size = desired_size;
1655 ai_flags = ai_family = ai_socktype = ai_protocol = 0;
1657 ai_flags = hints->ai_flags;
1658 ai_family = hints->ai_family;
1659 ai_socktype = hints->ai_socktype;
1660 ai_protocol = hints->ai_protocol;
1664 memcpy(p, &res_options, sizeof(res_options));
1665 p += sizeof(res_options);
1667 memcpy(p, &op_id, sizeof(int));
1670 memcpy(p, &ai_flags, sizeof(int));
1673 memcpy(p, &ai_family, sizeof(int));
1676 memcpy(p, &ai_socktype, sizeof(int));
1679 memcpy(p, &ai_protocol, sizeof(int));
1682 if (hostname != NULL)
1683 memcpy(p, hostname, size);
1685 *buffer_size = desired_size;
1686 return (NS_SUCCESS);
1690 addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval,
1691 va_list ap, void *cache_mdata)
1693 struct addrinfo *ai, *cai;
1695 size_t desired_size, size, ai_size;
1697 ai = *((struct addrinfo **)retval);
1699 desired_size = sizeof(size_t);
1701 for (cai = ai; cai != NULL; cai = cai->ai_next) {
1702 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen;
1703 if (cai->ai_canonname != NULL)
1704 desired_size += sizeof(size_t) +
1705 strlen(cai->ai_canonname);
1709 if (desired_size > *buffer_size) {
1710 /* this assignment is here for future use */
1712 *buffer_size = desired_size;
1716 memset(buffer, 0, desired_size);
1719 memcpy(p, &ai_size, sizeof(size_t));
1720 p += sizeof(size_t);
1721 for (cai = ai; cai != NULL; cai = cai->ai_next) {
1722 memcpy(p, cai, sizeof(struct addrinfo));
1723 p += sizeof(struct addrinfo);
1725 memcpy(p, cai->ai_addr, cai->ai_addrlen);
1726 p += cai->ai_addrlen;
1728 if (cai->ai_canonname != NULL) {
1729 size = strlen(cai->ai_canonname);
1730 memcpy(p, &size, sizeof(size_t));
1731 p += sizeof(size_t);
1733 memcpy(p, cai->ai_canonname, size);
1738 return (NS_SUCCESS);
1742 addrinfo_unmarshal_func(char *buffer, size_t buffer_size, void *retval,
1743 va_list ap, void *cache_mdata)
1745 struct addrinfo new_ai, *result, *sentinel, *lasts;
1748 size_t ai_size, ai_i, size;
1751 memcpy(&ai_size, p, sizeof(size_t));
1752 p += sizeof(size_t);
1756 for (ai_i = 0; ai_i < ai_size; ++ai_i) {
1757 memcpy(&new_ai, p, sizeof(struct addrinfo));
1758 p += sizeof(struct addrinfo);
1759 size = new_ai.ai_addrlen + sizeof(struct addrinfo) +
1762 sentinel = (struct addrinfo *)malloc(size);
1763 memset(sentinel, 0, size);
1765 memcpy(sentinel, &new_ai, sizeof(struct addrinfo));
1766 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel +
1767 sizeof(struct addrinfo));
1769 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen);
1770 p += new_ai.ai_addrlen;
1772 if (new_ai.ai_canonname != NULL) {
1773 memcpy(&size, p, sizeof(size_t));
1774 p += sizeof(size_t);
1776 sentinel->ai_canonname = (char *)malloc(size + 1);
1777 memset(sentinel->ai_canonname, 0, size + 1);
1779 memcpy(sentinel->ai_canonname, p, size);
1783 if (result == NULL) {
1787 lasts->ai_next = sentinel;
1792 *((struct addrinfo **)retval) = result;
1793 return (NS_SUCCESS);
1795 #endif /* NS_CACHING */
1798 * FQDN hostname, DNS lookup
1801 explore_fqdn(const struct addrinfo *pai, const char *hostname,
1802 const char *servname, struct addrinfo **res)
1804 struct addrinfo *result;
1805 struct addrinfo *cur;
1809 static const nss_cache_info cache_info =
1810 NS_COMMON_CACHE_INFO_INITIALIZER(
1811 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func,
1812 addrinfo_unmarshal_func);
1814 static const ns_dtab dtab[] = {
1815 NS_FILES_CB(_files_getaddrinfo, NULL)
1816 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */
1817 NS_NIS_CB(_yp_getaddrinfo, NULL)
1819 NS_CACHE_CB(&cache_info)
1827 * if the servname does not match socktype/protocol, ignore it.
1829 if (get_portmatch(pai, servname) != 0)
1832 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo",
1833 default_dns_files, hostname, pai)) {
1845 for (cur = result; cur; cur = cur->ai_next) {
1846 GET_PORT(cur, servname);
1847 /* canonname should be filled already */
1858 freeaddrinfo(result);
1863 static const char AskedForGot[] =
1864 "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
1867 static struct addrinfo *
1868 getanswer(const querybuf *answer, int anslen, const char *qname, int qtype,
1869 const struct addrinfo *pai, res_state res)
1871 struct addrinfo sentinel, *cur;
1873 const struct afd *afd;
1880 int type, class, ancount, qdcount;
1881 int haveanswer, had_error;
1882 char tbuf[MAXDNAME];
1883 int (*name_ok)(const char *);
1884 char hostbuf[8*1024];
1886 memset(&sentinel, 0, sizeof(sentinel));
1890 eom = answer->buf + anslen;
1894 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/
1898 return (NULL); /* XXX should be abort(); */
1901 * find first satisfactory answer
1904 ancount = ntohs(hp->ancount);
1905 qdcount = ntohs(hp->qdcount);
1907 ep = hostbuf + sizeof hostbuf;
1908 cp = answer->buf + HFIXEDSZ;
1910 RES_SET_H_ERRNO(res, NO_RECOVERY);
1913 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1914 if ((n < 0) || !(*name_ok)(bp)) {
1915 RES_SET_H_ERRNO(res, NO_RECOVERY);
1919 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
1920 /* res_send() has already verified that the query name is the
1921 * same as the one we sent; this just gets the expanded name
1922 * (i.e., with the succeeding search-domain tacked on).
1924 n = strlen(bp) + 1; /* for the \0 */
1925 if (n >= MAXHOSTNAMELEN) {
1926 RES_SET_H_ERRNO(res, NO_RECOVERY);
1931 /* The qname can be abbreviated, but h_name is now absolute. */
1936 while (ancount-- > 0 && cp < eom && !had_error) {
1937 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1938 if ((n < 0) || !(*name_ok)(bp)) {
1943 type = _getshort(cp);
1944 cp += INT16SZ; /* type */
1945 class = _getshort(cp);
1946 cp += INT16SZ + INT32SZ; /* class, TTL */
1948 cp += INT16SZ; /* len */
1949 if (class != C_IN) {
1950 /* XXX - debug? syslog? */
1952 continue; /* XXX - had_error++ ? */
1954 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
1956 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
1957 if ((n < 0) || !(*name_ok)(tbuf)) {
1962 /* Get canonical name. */
1963 n = strlen(tbuf) + 1; /* for the \0 */
1964 if (n > ep - bp || n >= MAXHOSTNAMELEN) {
1968 strlcpy(bp, tbuf, ep - bp);
1973 if (qtype == T_ANY) {
1974 if (!(type == T_A || type == T_AAAA)) {
1978 } else if (type != qtype) {
1980 if (type != T_KEY && type != T_SIG &&
1982 syslog(LOG_NOTICE|LOG_AUTH,
1983 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
1984 qname, p_class(C_IN), p_type(qtype),
1988 continue; /* XXX - had_error++ ? */
1993 if (strcasecmp(canonname, bp) != 0) {
1995 syslog(LOG_NOTICE|LOG_AUTH,
1996 AskedForGot, canonname, bp);
1999 continue; /* XXX - had_error++ ? */
2001 if (type == T_A && n != INADDRSZ) {
2005 if (type == T_AAAA && n != IN6ADDRSZ) {
2009 #ifdef FILTER_V4MAPPED
2010 if (type == T_AAAA) {
2011 struct in6_addr in6;
2012 memcpy(&in6, cp, sizeof(in6));
2013 if (IN6_IS_ADDR_V4MAPPED(&in6)) {
2023 nn = strlen(bp) + 1; /* for the \0 */
2027 /* don't overwrite pai */
2029 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
2030 afd = find_afd(ai.ai_family);
2035 cur->ai_next = get_ai(&ai, afd, (const char *)cp);
2036 if (cur->ai_next == NULL)
2038 while (cur && cur->ai_next)
2049 #if defined(RESOLVSORT)
2051 * We support only IPv4 address for backward
2052 * compatibility against gethostbyname(3).
2054 if (res->nsort && qtype == T_A) {
2055 if (addr4sort(&sentinel, res) < 0) {
2056 freeaddrinfo(sentinel.ai_next);
2057 RES_SET_H_ERRNO(res, NO_RECOVERY);
2061 #endif /*RESOLVSORT*/
2063 (void)get_canonname(pai, sentinel.ai_next, qname);
2065 (void)get_canonname(pai, sentinel.ai_next, canonname);
2066 RES_SET_H_ERRNO(res, NETDB_SUCCESS);
2067 return sentinel.ai_next;
2070 RES_SET_H_ERRNO(res, NO_RECOVERY);
2076 struct addrinfo *ai;
2081 addr4sort(struct addrinfo *sentinel, res_state res)
2083 struct addrinfo *ai;
2084 struct addr_ptr *addrs, addr;
2085 struct sockaddr_in *sin;
2092 for (ai = sentinel->ai_next; ai; ai = ai->ai_next)
2095 return 0; /* We don't need sorting. */
2096 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL)
2099 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) {
2100 sin = (struct sockaddr_in *)ai->ai_addr;
2101 for (j = 0; (unsigned)j < res->nsort; j++) {
2102 if (res->sort_list[j].addr.s_addr ==
2103 (sin->sin_addr.s_addr & res->sort_list[j].mask))
2108 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval)
2117 while (needsort < naddrs) {
2118 for (j = needsort - 1; j >= 0; j--) {
2119 if (addrs[j].aval > addrs[j+1].aval) {
2121 addrs[j] = addrs[j + 1];
2122 addrs[j + 1] = addr;
2130 for (i = 0; i < naddrs; ++i) {
2131 ai->ai_next = addrs[i].ai;
2138 #endif /*RESOLVSORT*/
2142 _dns_getaddrinfo(void *rv, void *cb_data, va_list ap)
2144 struct addrinfo *ai;
2145 querybuf *buf, *buf2;
2146 const char *hostname;
2147 const struct addrinfo *pai;
2148 struct addrinfo sentinel, *cur;
2149 struct res_target q, q2;
2152 hostname = va_arg(ap, char *);
2153 pai = va_arg(ap, const struct addrinfo *);
2155 memset(&q, 0, sizeof(q));
2156 memset(&q2, 0, sizeof(q2));
2157 memset(&sentinel, 0, sizeof(sentinel));
2160 buf = malloc(sizeof(*buf));
2162 RES_SET_H_ERRNO(res, NETDB_INTERNAL);
2165 buf2 = malloc(sizeof(*buf2));
2168 RES_SET_H_ERRNO(res, NETDB_INTERNAL);
2172 switch (pai->ai_family) {
2177 q.answer = buf->buf;
2178 q.anslen = sizeof(buf->buf);
2183 q2.answer = buf2->buf;
2184 q2.anslen = sizeof(buf2->buf);
2190 q.answer = buf->buf;
2191 q.anslen = sizeof(buf->buf);
2197 q.answer = buf->buf;
2198 q.anslen = sizeof(buf->buf);
2206 res = __res_state();
2207 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) {
2208 RES_SET_H_ERRNO(res, NETDB_INTERNAL);
2214 if (res_searchN(hostname, &q, res) < 0) {
2221 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res);
2224 while (cur && cur->ai_next)
2228 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res);
2233 if (sentinel.ai_next == NULL)
2234 switch (res->res_h_errno) {
2235 case HOST_NOT_FOUND:
2242 *((struct addrinfo **)rv) = sentinel.ai_next;
2247 _sethtent(FILE **hostf)
2250 *hostf = fopen(_PATH_HOSTS, "re");
2256 _endhtent(FILE **hostf)
2259 (void) fclose(*hostf);
2264 static struct addrinfo *
2265 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai)
2268 char *cp, *tname, *cname;
2269 struct addrinfo hints, *res0, *res;
2272 char hostbuf[8*1024];
2274 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re")))
2277 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf)))
2281 cp = strpbrk(p, "#\n");
2284 if (!(cp = strpbrk(p, " \t")))
2289 /* if this is not something we're looking for, skip it. */
2291 if (*cp == ' ' || *cp == '\t') {
2298 if ((cp = strpbrk(cp, " \t")) != NULL)
2300 if (strcasecmp(name, tname) == 0)
2306 /* we should not glob socktype/protocol here */
2307 memset(&hints, 0, sizeof(hints));
2308 hints.ai_family = pai->ai_family;
2309 hints.ai_socktype = SOCK_DGRAM;
2310 hints.ai_protocol = 0;
2311 hints.ai_flags = AI_NUMERICHOST;
2312 error = getaddrinfo(addr, "0", &hints, &res0);
2315 #ifdef FILTER_V4MAPPED
2316 /* XXX should check all items in the chain */
2317 if (res0->ai_family == AF_INET6 &&
2318 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) {
2323 for (res = res0; res; res = res->ai_next) {
2325 res->ai_flags = pai->ai_flags;
2326 res->ai_socktype = pai->ai_socktype;
2327 res->ai_protocol = pai->ai_protocol;
2329 if (pai->ai_flags & AI_CANONNAME) {
2330 if (get_canonname(pai, res, cname) != 0) {
2341 _files_getaddrinfo(void *rv, void *cb_data, va_list ap)
2344 const struct addrinfo *pai;
2345 struct addrinfo sentinel, *cur;
2349 name = va_arg(ap, char *);
2350 pai = va_arg(ap, struct addrinfo *);
2352 memset(&sentinel, 0, sizeof(sentinel));
2356 while ((p = _gethtent(&hostf, name, pai)) != NULL) {
2358 while (cur && cur->ai_next)
2363 *((struct addrinfo **)rv) = sentinel.ai_next;
2364 if (sentinel.ai_next == NULL)
2371 static struct addrinfo *
2372 _yphostent(char *line, const struct addrinfo *pai)
2374 struct addrinfo sentinel, *cur;
2375 struct addrinfo hints, *res, *res0;
2378 const char *addr, *canonname;
2382 addr = canonname = NULL;
2384 memset(&sentinel, 0, sizeof(sentinel));
2388 /* terminate line */
2389 cp = strchr(p, '\n');
2396 cp = strpbrk(p, " \t");
2398 if (canonname == NULL)
2408 if (*cp == ' ' || *cp == '\t') {
2414 if ((cp = strpbrk(cp, " \t")) != NULL)
2419 hints.ai_flags = AI_NUMERICHOST;
2420 error = getaddrinfo(addr, NULL, &hints, &res0);
2422 for (res = res0; res; res = res->ai_next) {
2424 res->ai_flags = pai->ai_flags;
2426 if (pai->ai_flags & AI_CANONNAME)
2427 (void)get_canonname(pai, res, canonname);
2432 cur->ai_next = res0;
2433 while (cur && cur->ai_next)
2443 return sentinel.ai_next;
2448 _yp_getaddrinfo(void *rv, void *cb_data, va_list ap)
2450 struct addrinfo sentinel, *cur;
2451 struct addrinfo *ai = NULL;
2455 const struct addrinfo *pai;
2458 if (_yp_check(&ypdomain) == 0)
2461 name = va_arg(ap, char *);
2462 pai = va_arg(ap, const struct addrinfo *);
2464 memset(&sentinel, 0, sizeof(sentinel));
2467 /* hosts.byname is only for IPv4 (Solaris8) */
2468 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) {
2469 r = yp_match(ypdomain, "hosts.byname", name,
2470 (int)strlen(name), &ypbuf, &ypbuflen);
2472 struct addrinfo ai4;
2475 ai4.ai_family = AF_INET;
2476 ai = _yphostent(ypbuf, &ai4);
2479 while (cur && cur->ai_next)
2486 /* ipnodes.byname can hold both IPv4/v6 */
2487 r = yp_match(ypdomain, "ipnodes.byname", name,
2488 (int)strlen(name), &ypbuf, &ypbuflen);
2490 ai = _yphostent(ypbuf, pai);
2496 if (sentinel.ai_next == NULL) {
2497 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND);
2500 *((struct addrinfo **)rv) = sentinel.ai_next;
2505 /* resolver logic */
2508 * Formulate a normal query, send, and await answer.
2509 * Returned answer is placed in supplied buffer "answer".
2510 * Perform preliminary check of answer, returning success only
2511 * if no error is indicated and the answer count is nonzero.
2512 * Return the size of the response on success, -1 on error.
2513 * Error number is left in h_errno.
2515 * Caller must parse answer and determine whether it answers the question.
2518 res_queryN(const char *name, struct res_target *target, res_state res)
2524 struct res_target *t;
2531 buf = malloc(MAXPACKET);
2533 RES_SET_H_ERRNO(res, NETDB_INTERNAL);
2537 for (t = target; t; t = t->next) {
2542 hp = (HEADER *)(void *)t->answer;
2544 /* make it easier... */
2550 oflags = res->_flags;
2553 hp->rcode = NOERROR; /* default */
2556 if (res->options & RES_DEBUG)
2557 printf(";; res_query(%s, %d, %d)\n", name, class, type);
2560 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL,
2562 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 &&
2563 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U)
2564 n = res_nopt(res, n, buf, MAXPACKET, anslen);
2567 if (res->options & RES_DEBUG)
2568 printf(";; res_query: mkquery failed\n");
2571 RES_SET_H_ERRNO(res, NO_RECOVERY);
2574 n = res_nsend(res, buf, n, answer, anslen);
2577 * if the query choked with EDNS0, retry
2580 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC))
2582 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) {
2583 res->_flags |= RES_F_EDNS0ERR;
2584 if (res->options & RES_DEBUG)
2585 printf(";; res_nquery: retry without EDNS0\n");
2588 rcode = hp->rcode; /* record most recent error */
2590 if (res->options & RES_DEBUG)
2591 printf(";; res_query: send error\n");
2597 hp->rcode = FORMERR; /* XXX not very informative */
2598 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
2599 rcode = hp->rcode; /* record most recent error */
2601 if (res->options & RES_DEBUG)
2602 printf(";; rcode = %u, ancount=%u\n", hp->rcode,
2603 ntohs(hp->ancount));
2608 ancount += ntohs(hp->ancount);
2618 RES_SET_H_ERRNO(res, HOST_NOT_FOUND);
2621 RES_SET_H_ERRNO(res, TRY_AGAIN);
2624 RES_SET_H_ERRNO(res, NO_DATA);
2630 RES_SET_H_ERRNO(res, NO_RECOVERY);
2639 * Formulate a normal query, send, and retrieve answer in supplied buffer.
2640 * Return the size of the response on success, -1 on error.
2641 * If enabled, implement search rules until answer or unrecoverable failure
2642 * is detected. Error code, if any, is left in h_errno.
2645 res_searchN(const char *name, struct res_target *target, res_state res)
2647 const char *cp, * const *domain;
2648 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/
2650 int trailing_dot, ret, saved_herrno;
2651 int got_nodata = 0, got_servfail = 0, root_on_list = 0;
2652 int tried_as_is = 0;
2654 char abuf[MAXDNAME];
2657 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */
2659 for (cp = name; *cp; cp++)
2660 dots += (*cp == '.');
2662 if (cp > name && *--cp == '.')
2666 * if there aren't any dots, it could be a user-level alias
2669 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL)
2670 return (res_queryN(cp, target, res));
2673 * If there are enough dots in the name, let's just give it a
2674 * try 'as is'. The threshold can be set with the "ndots" option.
2675 * Also, query 'as is', if there is a trailing dot in the name.
2678 if (dots >= res->ndots || trailing_dot) {
2679 ret = res_querydomainN(name, NULL, target, res);
2680 if (ret > 0 || trailing_dot)
2682 if (errno == ECONNREFUSED) {
2683 RES_SET_H_ERRNO(res, TRY_AGAIN);
2686 switch (res->res_h_errno) {
2688 case HOST_NOT_FOUND:
2691 if (hp->rcode == SERVFAIL)
2697 saved_herrno = res->res_h_errno;
2702 * We do at least one level of search if
2703 * - there is no dot and RES_DEFNAME is set, or
2704 * - there is at least one dot, there is no trailing dot,
2705 * and RES_DNSRCH is set.
2707 if ((!dots && (res->options & RES_DEFNAMES)) ||
2708 (dots && !trailing_dot && (res->options & RES_DNSRCH))) {
2711 for (domain = (const char * const *)res->dnsrch;
2716 if (domain[0][0] == '\0' ||
2717 (domain[0][0] == '.' && domain[0][1] == '\0'))
2720 if (root_on_list && tried_as_is)
2723 ret = res_querydomainN(name, *domain, target, res);
2728 * If no server present, give up.
2729 * If name isn't found in this domain,
2730 * keep trying higher domains in the search list
2731 * (if that's enabled).
2732 * On a NO_DATA error, keep trying, otherwise
2733 * a wildcard entry of another type could keep us
2734 * from finding this entry higher in the domain.
2735 * If we get some other error (negative answer or
2736 * server failure), then stop searching up,
2737 * but try the input name below in case it's
2740 if (errno == ECONNREFUSED) {
2741 RES_SET_H_ERRNO(res, TRY_AGAIN);
2745 switch (res->res_h_errno) {
2749 case HOST_NOT_FOUND:
2754 if (hp->rcode == SERVFAIL) {
2755 /* try next search element, if any */
2760 /* anything else implies that we're done */
2764 * if we got here for some reason other than DNSRCH,
2765 * we only wanted one iteration of the loop, so stop.
2767 if (!(res->options & RES_DNSRCH))
2772 switch (res->res_h_errno) {
2774 case HOST_NOT_FOUND:
2777 if (hp->rcode == SERVFAIL)
2785 * If the query has not already been tried as is then try it
2786 * unless RES_NOTLDQUERY is set and there were no dots.
2788 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) &&
2789 !(tried_as_is || root_on_list)) {
2790 ret = res_querydomainN(name, NULL, target, res);
2796 * if we got here, we didn't satisfy the search.
2797 * if we did an initial full query, return that query's h_errno
2798 * (note that we wouldn't be here if that query had succeeded).
2799 * else if we ever got a nodata, send that back as the reason.
2800 * else send back meaningless h_errno, that being the one from
2801 * the last DNSRCH we did.
2804 if (saved_herrno != -1)
2805 RES_SET_H_ERRNO(res, saved_herrno);
2806 else if (got_nodata)
2807 RES_SET_H_ERRNO(res, NO_DATA);
2808 else if (got_servfail)
2809 RES_SET_H_ERRNO(res, TRY_AGAIN);
2814 * Perform a call on res_query on the concatenation of name and domain,
2815 * removing a trailing dot from name if domain is NULL.
2818 res_querydomainN(const char *name, const char *domain,
2819 struct res_target *target, res_state res)
2821 char nbuf[MAXDNAME];
2822 const char *longname = nbuf;
2826 if (res->options & RES_DEBUG)
2827 printf(";; res_querydomain(%s, %s)\n",
2828 name, domain?domain:"<Nil>");
2830 if (domain == NULL) {
2832 * Check for trailing '.';
2833 * copy without '.' if present.
2836 if (n >= MAXDNAME) {
2837 RES_SET_H_ERRNO(res, NO_RECOVERY);
2840 if (n > 0 && name[--n] == '.') {
2841 strncpy(nbuf, name, n);
2848 if (n + d + 1 >= MAXDNAME) {
2849 RES_SET_H_ERRNO(res, NO_RECOVERY);
2852 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain);
2854 return (res_queryN(longname, target, res));