1/*	$NetBSD: getaddrinfo.c,v 1.119.2.1 2020/11/29 11:25:31 martin Exp $	*/
2/*	$KAME: getaddrinfo.c,v 1.29 2000/08/31 17:26:57 itojun Exp $	*/
3
4/*
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33/*
34 * Issues to be discussed:
35 * - Return values.  There are nonstandard return values defined and used
36 *   in the source code.  This is because RFC2553 is silent about which error
37 *   code must be returned for which situation.
38 * - IPv4 classful (shortened) form.  RFC2553 is silent about it.  XNET 5.2
39 *   says to use inet_aton() to convert IPv4 numeric to binary (alows
40 *   classful form as a result).
41 *   current code - disallow classful form for IPv4 (due to use of inet_pton).
42 * - freeaddrinfo(NULL).  RFC2553 is silent about it.  XNET 5.2 says it is
43 *   invalid.
44 *   current code - SEGV on freeaddrinfo(NULL)
45 * Note:
46 * - The code filters out AFs that are not supported by the kernel,
47 *   when globbing NULL hostname (to loopback, or wildcard).  Is it the right
48 *   thing to do?  What is the relationship with post-RFC2553 AI_ADDRCONFIG
49 *   in ai_flags?
50 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague.
51 *   (1) what should we do against numeric hostname (2) what should we do
52 *   against NULL hostname (3) what is AI_ADDRCONFIG itself.  AF not ready?
53 *   non-loopback address configured?  global address configured?
54 */
55
56#include <sys/cdefs.h>
57#if defined(LIBC_SCCS) && !defined(lint)
58__RCSID("$NetBSD: getaddrinfo.c,v 1.119.2.1 2020/11/29 11:25:31 martin Exp $");
59#endif /* LIBC_SCCS and not lint */
60#include "namespace.h"
61#include <sys/types.h>
62#include <sys/param.h>
63#include <sys/socket.h>
64#include <net/if.h>
65#include <netinet/in.h>
66#include <arpa/inet.h>
67#include <arpa/nameser.h>
68#include <assert.h>
69#include <ctype.h>
70#include <errno.h>
71#include <netdb.h>
72#include <resolv.h>
73#include <stddef.h>
74#include <stdio.h>
75#include <stdlib.h>
76#include <string.h>
77#include <unistd.h>
78#include <ifaddrs.h>
79
80#include <syslog.h>
81#include <stdarg.h>
82
83#ifdef YP
84#include <rpc/rpc.h>
85#include <rpcsvc/yp_prot.h>
86#include <rpcsvc/ypclnt.h>
87#endif
88
89#include <FindDirectory.h>
90
91#include <libutil.h>
92#include "nsswitch.h"
93#include "servent.h"
94
95#ifndef RUMP_ACTION
96#ifdef __weak_alias
97__weak_alias(getaddrinfo,_getaddrinfo)
98__weak_alias(allocaddrinfo,_allocaddrinfo)
99__weak_alias(freeaddrinfo,_freeaddrinfo)
100__weak_alias(gai_strerror,_gai_strerror)
101#endif
102#endif
103
104#define SUCCESS 0
105#define ANY 0
106#define YES 1
107#define NO  0
108
109#define sa4addr(sa) ((void *)&((struct sockaddr_in *)(void *)sa)->sin_addr)
110#define sa6addr(sa) ((void *)&((struct sockaddr_in6 *)(void *)sa)->sin6_addr)
111
112static const char in_addrany[] = { 0, 0, 0, 0 };
113static const char in_loopback[] = { 127, 0, 0, 1 };
114#ifdef INET6
115static const char in6_addrany[] = {
116	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
117};
118static const char in6_loopback[] = {
119	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
120};
121#endif
122
123struct policyqueue {
124	TAILQ_ENTRY(policyqueue) pc_entry;
125#if defined(INET6) && !defined(__HAIKU__)
126	struct in6_addrpolicy pc_policy;
127#endif
128};
129TAILQ_HEAD(policyhead, policyqueue);
130
131static const struct afd {
132	int a_af;
133	int a_addrlen;
134	int a_socklen;
135	int a_off;
136	const char *a_addrany;
137	const char *a_loopback;
138	int a_scoped;
139} afdl [] = {
140#ifdef INET6
141	{PF_INET6, sizeof(struct in6_addr),
142	 sizeof(struct sockaddr_in6),
143	 offsetof(struct sockaddr_in6, sin6_addr),
144	 in6_addrany, in6_loopback, 1},
145#endif
146	{PF_INET, sizeof(struct in_addr),
147	 sizeof(struct sockaddr_in),
148	 offsetof(struct sockaddr_in, sin_addr),
149	 in_addrany, in_loopback, 0},
150	{0, 0, 0, 0, NULL, NULL, 0},
151};
152
153struct explore {
154	int e_af;
155	int e_socktype;
156	int e_protocol;
157	const char *e_protostr;
158	int e_wild;
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)
162};
163
164static const struct explore explore[] = {
165#if 0
166	{ PF_LOCAL, 0, ANY, ANY, NULL, 0x01 },
167#endif
168#ifdef INET6
169	{ PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
170	{ PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
171	{ PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
172#endif
173	{ PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
174	{ PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
175	{ PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
176	{ PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
177	{ PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
178	{ PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 },
179	{ -1, 0, 0, NULL, 0 },
180};
181
182#ifdef INET6
183#define PTON_MAX	16
184#else
185#define PTON_MAX	4
186#endif
187
188#define AIO_SRCFLAG_DEPRECATED	0x1
189
190struct ai_order {
191	union {
192		struct sockaddr_storage aiou_ss;
193		struct sockaddr aiou_sa;
194	} aio_src_un;
195#define aio_srcsa aio_src_un.aiou_sa
196	u_int32_t aio_srcflag;
197	int aio_srcscope;
198	int aio_dstscope;
199	struct policyqueue *aio_srcpolicy;
200	struct policyqueue *aio_dstpolicy;
201	struct addrinfo *aio_ai;
202	int aio_matchlen;
203};
204
205static const ns_src default_dns_files[] = {
206	{ NSSRC_FILES,	NS_SUCCESS },
207	{ NSSRC_DNS,	NS_SUCCESS },
208	{ 0, 0 }
209};
210
211#define MAXPACKET	(64*1024)
212
213typedef union {
214	HEADER hdr;
215	u_char buf[MAXPACKET];
216} querybuf;
217
218struct res_target {
219	struct res_target *next;
220	const char *name;	/* domain name */
221	int qclass, qtype;	/* class and type of query */
222	u_char *answer;		/* buffer to put answer */
223	int anslen;		/* size of answer buffer */
224	int n;			/* result length */
225};
226
227struct srvinfo {
228       struct srvinfo *next;
229       char name[MAXDNAME];
230       int port, pri, weight;
231};
232
233static int gai_srvok(const char *);
234static int str2number(const char *);
235static int explore_fqdn(const struct addrinfo *, const char *,
236    const char *, struct addrinfo **, struct servent_data *);
237static int explore_null(const struct addrinfo *,
238    const char *, struct addrinfo **, struct servent_data *);
239static int explore_numeric(const struct addrinfo *, const char *,
240    const char *, struct addrinfo **, const char *, struct servent_data *);
241static int explore_numeric_scope(const struct addrinfo *, const char *,
242    const char *, struct addrinfo **, struct servent_data *);
243static int get_canonname(const struct addrinfo *,
244    struct addrinfo *, const char *);
245static struct addrinfo *get_ai(const struct addrinfo *,
246    const struct afd *, const char *);
247static int get_portmatch(const struct addrinfo *, const char *,
248    struct servent_data *);
249static int get_port(const struct addrinfo *, const char *, int,
250    struct servent_data *);
251static const struct afd *find_afd(int);
252static int addrconfig(uint64_t *);
253static void set_source(struct ai_order *, struct policyhead *,
254    struct servent_data *);
255static int comp_dst(const void *, const void *);
256#ifdef INET6
257static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *);
258#endif
259static int gai_addr2scopetype(struct sockaddr *);
260
261static int reorder(struct addrinfo *, struct servent_data *);
262static int get_addrselectpolicy(struct policyhead *);
263static void free_addrselectpolicy(struct policyhead *);
264static struct policyqueue *match_addrselectpolicy(struct sockaddr *,
265	struct policyhead *);
266static int matchlen(struct sockaddr *, struct sockaddr *);
267
268static struct addrinfo *getanswer(res_state, const querybuf *, int,
269    const char *, int, const struct addrinfo *);
270static void aisort(struct addrinfo *s, res_state res);
271static struct addrinfo * _dns_query(struct res_target *,
272    const struct addrinfo *, res_state, int);
273static struct addrinfo * _dns_srv_lookup(const char *, const char *,
274    const struct addrinfo *);
275static struct addrinfo * _dns_host_lookup(const char *,
276    const struct addrinfo *);
277static int _dns_getaddrinfo(void *, void *, va_list);
278static void _sethtent(FILE **);
279static void _endhtent(FILE **);
280static struct addrinfo *_gethtent(FILE **, const char *,
281    const struct addrinfo *);
282static int _files_getaddrinfo(void *, void *, va_list);
283#ifdef YP
284static struct addrinfo *_yphostent(char *, const struct addrinfo *);
285static int _yp_getaddrinfo(void *, void *, va_list);
286#endif
287
288static int res_queryN(const char *, struct res_target *, res_state);
289static int res_searchN(const char *, struct res_target *, res_state);
290static int res_querydomainN(const char *, const char *,
291    struct res_target *, res_state);
292
293static const char * const ai_errlist[] = {
294	"Success",
295	"Address family for hostname not supported",	/* EAI_ADDRFAMILY */
296	"Temporary failure in name resolution",		/* EAI_AGAIN	  */
297	"Invalid value for ai_flags",			/* EAI_BADFLAGS	  */
298	"Non-recoverable failure in name resolution",	/* EAI_FAIL	  */
299	"ai_family not supported",			/* EAI_FAMILY	  */
300	"Memory allocation failure",			/* EAI_MEMORY	  */
301	"No address associated with hostname",		/* EAI_NODATA	  */
302	"hostname or servname not provided or not known", /* EAI_NONAME	  */
303	"servname not supported for ai_socktype",	/* EAI_SERVICE	  */
304	"ai_socktype not supported",			/* EAI_SOCKTYPE	  */
305	"System error returned in errno",		/* EAI_SYSTEM	  */
306	"Invalid value for hints",			/* EAI_BADHINTS	  */
307	"Resolved protocol is unknown",			/* EAI_PROTOCOL	  */
308	"Argument buffer overflow",			/* EAI_OVERFLOW	  */
309	"Unknown error",				/* EAI_MAX	  */
310};
311
312/* XXX macros that make external reference is BAD. */
313
314#define GET_AI(ai, afd, addr)					\
315do {								\
316	/* external reference: pai, error, and label free */	\
317	(ai) = get_ai(pai, (afd), (addr));			\
318	if ((ai) == NULL) {					\
319		error = EAI_MEMORY;				\
320		goto free;					\
321	}							\
322} while (/*CONSTCOND*/0)
323
324#define GET_PORT(ai, serv, svd)					\
325do {								\
326	/* external reference: error and label free */		\
327	error = get_port((ai), (serv), 0, (svd));		\
328	if (error != 0)						\
329		goto free;					\
330} while (/*CONSTCOND*/0)
331
332#define GET_CANONNAME(ai, str)					\
333do {								\
334	/* external reference: pai, error and label free */	\
335	error = get_canonname(pai, (ai), (str));		\
336	if (error != 0)						\
337		goto free;					\
338} while (/*CONSTCOND*/0)
339
340#define ERR(err)						\
341do {								\
342	/* external reference: error, and label bad */		\
343	error = (err);						\
344	goto bad;						\
345	/*NOTREACHED*/						\
346} while (/*CONSTCOND*/0)
347
348#define MATCH_FAMILY(x, y, w)						\
349	((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC ||	\
350	    (y) == PF_UNSPEC)))
351#define MATCH(x, y, w)							\
352	((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
353
354const char *
355gai_strerror(int ecode)
356{
357	if (ecode < 0 || ecode > EAI_MAX)
358		ecode = EAI_MAX;
359	return ai_errlist[ecode];
360}
361
362void
363freeaddrinfo(struct addrinfo *ai)
364{
365	struct addrinfo *next;
366
367	_DIAGASSERT(ai != NULL);
368
369	do {
370		next = ai->ai_next;
371		if (ai->ai_canonname)
372			free(ai->ai_canonname);
373		/* no need to free(ai->ai_addr) */
374		free(ai);
375		ai = next;
376	} while (ai);
377}
378
379/*
380 * We don't want localization to affect us
381 */
382#define PERIOD '.'
383#define hyphenchar(c) ((c) == '-')
384#define periodchar(c) ((c) == PERIOD)
385#define underschar(c) ((c) == '_')
386#define alphachar(c) (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z'))
387#define digitchar(c) ((c) >= '0' && (c) <= '9')
388
389#define firstchar(c)  (alphachar(c) || digitchar(c) || underschar(c))
390#define lastchar(c)   (alphachar(c) || digitchar(c))
391#define middlechar(c) (lastchar(c) || hyphenchar(c))
392
393static int
394gai_srvok(const char *dn)
395{
396	int nch, pch, ch;
397
398	for (pch = PERIOD, nch = ch = *dn++; ch != '\0'; pch = ch, ch = nch) {
399		if (periodchar(ch))
400			continue;
401		if (periodchar(pch)) {
402			if (!firstchar(ch))
403				return 0;
404		} else if (periodchar(nch) || nch == '\0') {
405			if (!lastchar(ch))
406				return 0;
407		} else if (!middlechar(ch))
408			return 0;
409       }
410       return 1;
411}
412
413static in_port_t *
414getport(struct addrinfo *ai) {
415	static in_port_t p;
416
417	switch (ai->ai_family) {
418	case AF_INET:
419		return &((struct sockaddr_in *)(void *)ai->ai_addr)->sin_port;
420#ifdef INET6
421	case AF_INET6:
422		return &((struct sockaddr_in6 *)(void *)ai->ai_addr)->sin6_port;
423#endif
424	default:
425		p = 0;
426		/* XXX: abort()? */
427		return &p;
428	}
429}
430
431static int
432str2number(const char *p)
433{
434	char *ep;
435	unsigned long v;
436
437	_DIAGASSERT(p != NULL);
438
439	if (*p == '\0')
440		return -1;
441	ep = NULL;
442	errno = 0;
443	v = strtoul(p, &ep, 10);
444	if (errno == 0 && ep && *ep == '\0' && v <= INT_MAX)
445		return (int)v;
446	else
447		return -1;
448}
449
450int
451getaddrinfo(const char *hostname, const char *servname,
452    const struct addrinfo *hints, struct addrinfo **res)
453{
454	struct addrinfo sentinel;
455	struct addrinfo *cur;
456	int error = 0;
457	struct addrinfo ai;
458	struct addrinfo ai0;
459	struct addrinfo *pai;
460	const struct explore *ex;
461	struct servent_data svd;
462	uint64_t mask = (uint64_t)~0ULL;
463	int numeric = 0;
464
465	/* hostname is allowed to be NULL */
466	/* servname is allowed to be NULL */
467	/* hints is allowed to be NULL */
468	_DIAGASSERT(res != NULL);
469
470	(void)memset(&svd, 0, sizeof(svd));
471	memset(&sentinel, 0, sizeof(sentinel));
472	cur = &sentinel;
473	memset(&ai, 0, sizeof(ai));
474	pai = &ai;
475	pai->ai_flags = 0;
476	pai->ai_family = PF_UNSPEC;
477	pai->ai_socktype = ANY;
478	pai->ai_protocol = ANY;
479	pai->ai_addrlen = 0;
480	pai->ai_canonname = NULL;
481	pai->ai_addr = NULL;
482	pai->ai_next = NULL;
483
484	if (hostname == NULL && servname == NULL)
485		return EAI_NONAME;
486	if (hints) {
487		/* error check for hints */
488		if (hints->ai_addrlen || hints->ai_canonname ||
489		    hints->ai_addr || hints->ai_next)
490			ERR(EAI_BADHINTS); /* xxx */
491		if (hints->ai_flags & ~AI_MASK)
492			ERR(EAI_BADFLAGS);
493		switch (hints->ai_family) {
494		case PF_UNSPEC:
495		case PF_INET:
496#ifdef INET6
497		case PF_INET6:
498#endif
499			break;
500		default:
501			ERR(EAI_FAMILY);
502		}
503		memcpy(pai, hints, sizeof(*pai));
504
505		/*
506		 * if both socktype/protocol are specified, check if they
507		 * are meaningful combination.
508		 */
509		if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
510			for (ex = explore; ex->e_af >= 0; ex++) {
511				if (pai->ai_family != ex->e_af)
512					continue;
513				if (ex->e_socktype == ANY)
514					continue;
515				if (ex->e_protocol == ANY)
516					continue;
517				if (pai->ai_socktype == ex->e_socktype
518				 && pai->ai_protocol != ex->e_protocol) {
519					ERR(EAI_BADHINTS);
520				}
521			}
522		}
523	}
524
525	if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && addrconfig(&mask) == -1)
526		ERR(EAI_FAIL);
527
528	/*
529	 * check for special cases.  (1) numeric servname is disallowed if
530	 * socktype/protocol are left unspecified. (2) servname is disallowed
531	 * for raw and other inet{,6} sockets.
532	 */
533	if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
534#ifdef PF_INET6
535	 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
536#endif
537	    ) {
538		ai0 = *pai;	/* backup *pai */
539
540		if (pai->ai_family == PF_UNSPEC) {
541#ifdef PF_INET6
542			pai->ai_family = PF_INET6;
543#else
544			pai->ai_family = PF_INET;
545#endif
546		}
547		error = get_portmatch(pai, servname, &svd);
548		if (error)
549			goto bad;
550
551		*pai = ai0;
552	}
553
554	ai0 = *pai;
555
556	/* NULL hostname, or numeric hostname */
557	for (ex = explore; ex->e_af >= 0; ex++) {
558		*pai = ai0;
559
560		/* ADDRCONFIG check */
561		if ((((uint64_t)1 << ex->e_af) & mask) == 0)
562			continue;
563
564		/* PF_UNSPEC entries are prepared for DNS queries only */
565		if (ex->e_af == PF_UNSPEC)
566			continue;
567
568		if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
569			continue;
570		if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex)))
571			continue;
572		if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex)))
573			continue;
574		if (pai->ai_family == PF_UNSPEC)
575			pai->ai_family = ex->e_af;
576		if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
577			pai->ai_socktype = ex->e_socktype;
578		if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
579			pai->ai_protocol = ex->e_protocol;
580
581		if (hostname == NULL)
582			error = explore_null(pai, servname, &cur->ai_next,
583			    &svd);
584		else
585			error = explore_numeric_scope(pai, hostname, servname,
586			    &cur->ai_next, &svd);
587
588		if (error)
589			goto free;
590
591		while (cur->ai_next)
592			cur = cur->ai_next;
593	}
594
595	/*
596	 * XXX
597	 * If numeric representation of AF1 can be interpreted as FQDN
598	 * representation of AF2, we need to think again about the code below.
599	 */
600	if (sentinel.ai_next) {
601		numeric = 1;
602		goto good;
603	}
604
605	if (hostname == NULL)
606		ERR(EAI_NODATA);
607	if (pai->ai_flags & AI_NUMERICHOST)
608		ERR(EAI_NONAME);
609
610	/*
611	 * hostname as alphabetical name.
612	 * we would like to prefer AF_INET6 than AF_INET, so we'll make a
613	 * outer loop by AFs.
614	 */
615	for (ex = explore; ex->e_af >= 0; ex++) {
616		*pai = ai0;
617
618
619		/* ADDRCONFIG check */
620		/* PF_UNSPEC entries are prepared for DNS queries only */
621		if (ex->e_af != PF_UNSPEC &&
622		    (((uint64_t)1 << ex->e_af) & mask) == 0)
623			continue;
624
625		/* require exact match for family field */
626		if (pai->ai_family != ex->e_af)
627			continue;
628
629		if (!MATCH(pai->ai_socktype, ex->e_socktype,
630				WILD_SOCKTYPE(ex))) {
631			continue;
632		}
633		if (!MATCH(pai->ai_protocol, ex->e_protocol,
634				WILD_PROTOCOL(ex))) {
635			continue;
636		}
637
638		if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
639			pai->ai_socktype = ex->e_socktype;
640		if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
641			pai->ai_protocol = ex->e_protocol;
642
643		error = explore_fqdn(pai, hostname, servname, &cur->ai_next,
644		    &svd);
645
646#ifndef __HAIKU__
647		while (cur && cur->ai_next)
648			cur = cur->ai_next;
649#else
650		while (cur && cur->ai_next) {
651			if ((((uint64_t)1 << cur->ai_next->ai_family) & mask) == 0) {
652				/* entry does not match addrconfig mask, remove from list */
653				struct addrinfo* removed = cur->ai_next;
654				cur->ai_next = removed->ai_next;
655				removed->ai_next = NULL;
656				freeaddrinfo(removed);
657			} else {
658				/* entry does match, keep it in list and move to next one */
659				cur = cur->ai_next;
660			}
661		}
662#endif
663	}
664
665	/* XXX */
666	if (sentinel.ai_next)
667		error = 0;
668
669	if (error)
670		goto free;
671
672	if (sentinel.ai_next) {
673 good:
674		/*
675		 * If the returned entry is for an active connection,
676		 * and the given name is not numeric, reorder the
677		 * list, so that the application would try the list
678		 * in the most efficient order.  Since the head entry
679		 * of the original list may contain ai_canonname and
680		 * that entry may be moved elsewhere in the new list,
681		 * we keep the pointer and will  restore it in the new
682		 * head entry.  (Note that RFC3493 requires the head
683		 * entry store it when requested by the caller).
684		 */
685		if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) {
686			if (!numeric) {
687				char *canonname;
688
689				canonname = sentinel.ai_next->ai_canonname;
690				sentinel.ai_next->ai_canonname = NULL;
691				(void)reorder(&sentinel, &svd);
692				if (sentinel.ai_next->ai_canonname == NULL) {
693					sentinel.ai_next->ai_canonname
694					    = canonname;
695				} else if (canonname != NULL)
696					free(canonname);
697			}
698		}
699		endservent_r(&svd);
700		*res = sentinel.ai_next;
701		return SUCCESS;
702	} else
703		error = EAI_FAIL;
704 free:
705 bad:
706	endservent_r(&svd);
707	if (sentinel.ai_next)
708		freeaddrinfo(sentinel.ai_next);
709	*res = NULL;
710	return error;
711}
712
713static int
714reorder(struct addrinfo *sentinel, struct servent_data *svd)
715{
716	struct addrinfo *ai, **aip;
717	struct ai_order *aio;
718	int i, n;
719	struct policyhead policyhead;
720
721	/* count the number of addrinfo elements for sorting. */
722	for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++)
723		;
724
725	/*
726	 * If the number is small enough, we can skip the reordering process.
727	 */
728	if (n <= 1)
729		return n;
730
731	/* allocate a temporary array for sort and initialization of it. */
732	if ((aio = malloc(sizeof(*aio) * n)) == NULL)
733		return n;	/* give up reordering */
734	memset(aio, 0, sizeof(*aio) * n);
735
736	/* retrieve address selection policy from the kernel */
737	TAILQ_INIT(&policyhead);
738	if (!get_addrselectpolicy(&policyhead)) {
739		/* no policy is installed into kernel, we don't sort. */
740		free(aio);
741		return n;
742	}
743
744	for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) {
745		aio[i].aio_ai = ai;
746		aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr);
747		aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr,
748							      &policyhead);
749		set_source(&aio[i], &policyhead, svd);
750	}
751
752	/* perform sorting. */
753	qsort(aio, n, sizeof(*aio), comp_dst);
754
755	/* reorder the addrinfo chain. */
756	for (i = 0, aip = &sentinel->ai_next; i < n; i++) {
757		*aip = aio[i].aio_ai;
758		aip = &aio[i].aio_ai->ai_next;
759	}
760	*aip = NULL;
761
762	/* cleanup and return */
763	free(aio);
764	free_addrselectpolicy(&policyhead);
765	return n;
766}
767
768static int
769get_addrselectpolicy(struct policyhead *head)
770{
771#if defined(INET6) && !defined(__HAIKU__)
772	static const int mib[] = {
773	    CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY };
774	static const u_int miblen = (u_int)__arraycount(mib);
775	size_t l;
776	char *buf;
777	struct in6_addrpolicy *pol, *ep;
778
779	if (sysctl(mib, miblen, NULL, &l, NULL, 0) < 0)
780		return 0;
781	if (l == 0)
782		return 0;
783	if ((buf = malloc(l)) == NULL)
784		return 0;
785	if (sysctl(mib, miblen, buf, &l, NULL, 0) < 0) {
786		free(buf);
787		return 0;
788	}
789
790	ep = (void *)(buf + l);
791	for (pol = (void *)buf; pol + 1 <= ep; pol++) {
792		struct policyqueue *new;
793
794		if ((new = malloc(sizeof(*new))) == NULL) {
795			free_addrselectpolicy(head); /* make the list empty */
796			break;
797		}
798		new->pc_policy = *pol;
799		TAILQ_INSERT_TAIL(head, new, pc_entry);
800	}
801
802	free(buf);
803	return 1;
804#else
805	return 0;
806#endif
807}
808
809static void
810free_addrselectpolicy(struct policyhead *head)
811{
812	struct policyqueue *ent, *nent;
813
814	for (ent = TAILQ_FIRST(head); ent; ent = nent) {
815		nent = TAILQ_NEXT(ent, pc_entry);
816		TAILQ_REMOVE(head, ent, pc_entry);
817		free(ent);
818	}
819}
820
821static struct policyqueue *
822match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head)
823{
824#if defined(INET6) && !defined(__HAIKU__)
825	struct policyqueue *ent, *bestent = NULL;
826	struct in6_addrpolicy *pol;
827	int curmatchlen, bestmatchlen = -1;
828	u_char *mp, *ep, *k, *p;
829	u_int m;
830	struct sockaddr_in6 key;
831
832	switch(addr->sa_family) {
833	case AF_INET6:
834		memcpy(&key, addr, sizeof(key));
835		break;
836	case AF_INET:
837		/* convert the address into IPv4-mapped IPv6 address. */
838		memset(&key, 0, sizeof(key));
839		key.sin6_family = AF_INET6;
840		key.sin6_len = sizeof(key);
841		key.sin6_addr.s6_addr[10] = 0xff;
842		key.sin6_addr.s6_addr[11] = 0xff;
843		memcpy(&key.sin6_addr.s6_addr[12], sa4addr(addr), 4);
844		break;
845	default:
846		return NULL;
847	}
848
849	for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) {
850		pol = &ent->pc_policy;
851		curmatchlen = 0;
852
853		mp = (void *)&pol->addrmask.sin6_addr;
854		ep = mp + 16;	/* XXX: scope field? */
855		k = (void *)&key.sin6_addr;
856		p = (void *)&pol->addr.sin6_addr;
857		for (; mp < ep && *mp; mp++, k++, p++) {
858			m = *mp;
859			if ((*k & m) != *p)
860				goto next; /* not match */
861			if (m == 0xff) /* short cut for a typical case */
862				curmatchlen += 8;
863			else {
864				while (m >= 0x80) {
865					curmatchlen++;
866					m <<= 1;
867				}
868			}
869		}
870
871		/* matched.  check if this is better than the current best. */
872		if (curmatchlen > bestmatchlen) {
873			bestent = ent;
874			bestmatchlen = curmatchlen;
875		}
876
877	  next:
878		continue;
879	}
880
881	return bestent;
882#else
883	return NULL;
884#endif
885
886}
887
888static void
889set_source(struct ai_order *aio, struct policyhead *ph,
890    struct servent_data *svd)
891{
892	struct addrinfo ai = *aio->aio_ai;
893	struct sockaddr_storage ss;
894	socklen_t srclen;
895	int s;
896
897	/* set unspec ("no source is available"), just in case */
898	aio->aio_srcsa.sa_family = AF_UNSPEC;
899	aio->aio_srcscope = -1;
900
901	switch(ai.ai_family) {
902	case AF_INET:
903#ifdef INET6
904	case AF_INET6:
905#endif
906		break;
907	default:		/* ignore unsupported AFs explicitly */
908		return;
909	}
910
911	/* XXX: make a dummy addrinfo to call connect() */
912	ai.ai_socktype = SOCK_DGRAM;
913	ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */
914	ai.ai_next = NULL;
915	memset(&ss, 0, sizeof(ss));
916	memcpy(&ss, ai.ai_addr, ai.ai_addrlen);
917	ai.ai_addr = (void *)&ss;
918	get_port(&ai, "1", 0, svd);
919
920#ifndef SOCK_CLOEXEC
921#define SOCK_CLOEXEC 0
922#endif
923
924	/* open a socket to get the source address for the given dst */
925	if ((s = socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC,
926	    ai.ai_protocol)) < 0)
927		return;		/* give up */
928#if SOCK_CLOEXEC == 0
929	fcntl(s, F_SETFD, FD_CLOEXEC);
930#endif
931	if (connect(s, ai.ai_addr, ai.ai_addrlen) < 0)
932		goto cleanup;
933	srclen = ai.ai_addrlen;
934	if (getsockname(s, &aio->aio_srcsa, &srclen) < 0) {
935		aio->aio_srcsa.sa_family = AF_UNSPEC;
936		goto cleanup;
937	}
938	aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa);
939	aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph);
940	aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr);
941#if defined(INET6) && !defined(__HAIKU__)
942	if (ai.ai_family == AF_INET6) {
943		struct in6_ifreq ifr6;
944		u_int32_t flags6;
945
946		memset(&ifr6, 0, sizeof(ifr6));
947		memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen);
948		if (ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) {
949			flags6 = ifr6.ifr_ifru.ifru_flags6;
950			if ((flags6 & IN6_IFF_DEPRECATED))
951				aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED;
952		}
953	}
954#endif
955
956  cleanup:
957	close(s);
958	return;
959}
960
961static int
962matchlen(struct sockaddr *src, struct sockaddr *dst)
963{
964	int match = 0;
965	u_char *s, *d;
966	u_char *lim;
967	u_int r, addrlen;
968
969	switch (src->sa_family) {
970#ifdef INET6
971	case AF_INET6:
972		s = sa6addr(src);
973		d = sa6addr(dst);
974		addrlen = sizeof(struct in6_addr);
975		lim = s + addrlen;
976		break;
977#endif
978	case AF_INET:
979		s = sa4addr(src);
980		d = sa4addr(dst);
981		addrlen = sizeof(struct in_addr);
982		lim = s + addrlen;
983		break;
984	default:
985		return 0;
986	}
987
988	while (s < lim)
989		if ((r = (*d++ ^ *s++)) != 0) {
990			while (r < addrlen * 8) {
991				match++;
992				r <<= 1;
993			}
994			break;
995		} else
996			match += 8;
997	return match;
998}
999
1000static int
1001comp_dst(const void *arg1, const void *arg2)
1002{
1003	const struct ai_order *dst1 = arg1, *dst2 = arg2;
1004
1005	/*
1006	 * Rule 1: Avoid unusable destinations.
1007	 * XXX: we currently do not consider if an appropriate route exists.
1008	 */
1009	if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
1010	    dst2->aio_srcsa.sa_family == AF_UNSPEC) {
1011		return -1;
1012	}
1013	if (dst1->aio_srcsa.sa_family == AF_UNSPEC &&
1014	    dst2->aio_srcsa.sa_family != AF_UNSPEC) {
1015		return 1;
1016	}
1017
1018	/* Rule 2: Prefer matching scope. */
1019	if (dst1->aio_dstscope == dst1->aio_srcscope &&
1020	    dst2->aio_dstscope != dst2->aio_srcscope) {
1021		return -1;
1022	}
1023	if (dst1->aio_dstscope != dst1->aio_srcscope &&
1024	    dst2->aio_dstscope == dst2->aio_srcscope) {
1025		return 1;
1026	}
1027
1028	/* Rule 3: Avoid deprecated addresses. */
1029	if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
1030	    dst2->aio_srcsa.sa_family != AF_UNSPEC) {
1031		if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
1032		    (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
1033			return -1;
1034		}
1035		if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
1036		    !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
1037			return 1;
1038		}
1039	}
1040
1041	/* Rule 4: Prefer home addresses. */
1042	/* XXX: not implemented yet */
1043
1044	/* Rule 5: Prefer matching label. */
1045#if defined(INET6) && !defined(__HAIKU__)
1046	if (dst1->aio_srcpolicy && dst1->aio_dstpolicy &&
1047	    dst1->aio_srcpolicy->pc_policy.label ==
1048	    dst1->aio_dstpolicy->pc_policy.label &&
1049	    (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL ||
1050	     dst2->aio_srcpolicy->pc_policy.label !=
1051	     dst2->aio_dstpolicy->pc_policy.label)) {
1052		return -1;
1053	}
1054	if (dst2->aio_srcpolicy && dst2->aio_dstpolicy &&
1055	    dst2->aio_srcpolicy->pc_policy.label ==
1056	    dst2->aio_dstpolicy->pc_policy.label &&
1057	    (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL ||
1058	     dst1->aio_srcpolicy->pc_policy.label !=
1059	     dst1->aio_dstpolicy->pc_policy.label)) {
1060		return 1;
1061	}
1062#endif
1063
1064	/* Rule 6: Prefer higher precedence. */
1065#if defined(INET6) && !defined(__HAIKU__)
1066	if (dst1->aio_dstpolicy &&
1067	    (dst2->aio_dstpolicy == NULL ||
1068	     dst1->aio_dstpolicy->pc_policy.preced >
1069	     dst2->aio_dstpolicy->pc_policy.preced)) {
1070		return -1;
1071	}
1072	if (dst2->aio_dstpolicy &&
1073	    (dst1->aio_dstpolicy == NULL ||
1074	     dst2->aio_dstpolicy->pc_policy.preced >
1075	     dst1->aio_dstpolicy->pc_policy.preced)) {
1076		return 1;
1077	}
1078#endif
1079
1080	/* Rule 7: Prefer native transport. */
1081	/* XXX: not implemented yet */
1082
1083	/* Rule 8: Prefer smaller scope. */
1084	if (dst1->aio_dstscope >= 0 &&
1085	    dst1->aio_dstscope < dst2->aio_dstscope) {
1086		return -1;
1087	}
1088	if (dst2->aio_dstscope >= 0 &&
1089	    dst2->aio_dstscope < dst1->aio_dstscope) {
1090		return 1;
1091	}
1092
1093	/*
1094	 * Rule 9: Use longest matching prefix.
1095	 * We compare the match length in a same AF only.
1096	 */
1097	if (dst1->aio_ai->ai_addr->sa_family ==
1098	    dst2->aio_ai->ai_addr->sa_family &&
1099	    dst1->aio_ai->ai_addr->sa_family != AF_INET) {
1100		if (dst1->aio_matchlen > dst2->aio_matchlen) {
1101			return -1;
1102		}
1103		if (dst1->aio_matchlen < dst2->aio_matchlen) {
1104			return 1;
1105		}
1106	}
1107
1108	/* Rule 10: Otherwise, leave the order unchanged. */
1109	return -1;
1110}
1111
1112/*
1113 * Copy from scope.c.
1114 * XXX: we should standardize the functions and link them as standard
1115 * library.
1116 */
1117static int
1118gai_addr2scopetype(struct sockaddr *sa)
1119{
1120#ifdef INET6
1121	struct sockaddr_in6 *sa6;
1122#endif
1123	struct sockaddr_in *sa4;
1124	u_char *p;
1125
1126	switch(sa->sa_family) {
1127#ifdef INET6
1128	case AF_INET6:
1129		sa6 = (void *)sa;
1130		if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
1131			/* just use the scope field of the multicast address */
1132			return sa6->sin6_addr.s6_addr[2] & 0x0f;
1133		}
1134		/*
1135		 * Unicast addresses: map scope type to corresponding scope
1136		 * value defined for multcast addresses.
1137		 * XXX: hardcoded scope type values are bad...
1138		 */
1139		if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr))
1140			return 1; /* node local scope */
1141		if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr))
1142			return 2; /* link-local scope */
1143		if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr))
1144			return 5; /* site-local scope */
1145		return 14;	/* global scope */
1146#endif
1147	case AF_INET:
1148		/*
1149		 * IPv4 pseudo scoping according to RFC 3484.
1150		 */
1151		sa4 = (void *)sa;
1152		p = (u_char *)(void *)&sa4->sin_addr;
1153		/* IPv4 autoconfiguration addresses have link-local scope. */
1154		if (p[0] == 169 && p[1] == 254)
1155			return 2;
1156		/* Private addresses have site-local scope. */
1157		if (p[0] == 10 ||
1158		    (p[0] == 172 && (p[1] & 0xf0) == 16) ||
1159		    (p[0] == 192 && p[1] == 168))
1160			return 14;	/* XXX: It should be 5 unless NAT */
1161		/* Loopback addresses have link-local scope. */
1162		if (p[0] == 127)
1163			return 2;
1164		return 14;
1165	default:
1166		errno = EAFNOSUPPORT; /* is this a good error? */
1167		return -1;
1168	}
1169}
1170
1171/*
1172 * FQDN hostname, DNS lookup
1173 */
1174static int
1175explore_fqdn(const struct addrinfo *pai, const char *hostname,
1176    const char *servname, struct addrinfo **res, struct servent_data *svd)
1177{
1178	struct addrinfo *result;
1179	struct addrinfo *cur;
1180	int error = 0;
1181	static const ns_dtab dtab[] = {
1182		NS_FILES_CB(_files_getaddrinfo, NULL)
1183		{ NSSRC_DNS, _dns_getaddrinfo, NULL },	/* force -DHESIOD */
1184		NS_NIS_CB(_yp_getaddrinfo, NULL)
1185		NS_NULL_CB
1186	};
1187
1188	_DIAGASSERT(pai != NULL);
1189	/* hostname may be NULL */
1190	/* servname may be NULL */
1191	_DIAGASSERT(res != NULL);
1192
1193	result = NULL;
1194
1195	/*
1196	 * if the servname does not match socktype/protocol, ignore it.
1197	 */
1198	if (get_portmatch(pai, servname, svd) != 0)
1199		return 0;
1200
1201	switch (nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo",
1202	    default_dns_files, hostname, pai, servname)) {
1203	case NS_TRYAGAIN:
1204		error = EAI_AGAIN;
1205		goto free;
1206	case NS_UNAVAIL:
1207		error = EAI_FAIL;
1208		goto free;
1209	case NS_NOTFOUND:
1210		error = EAI_NODATA;
1211		goto free;
1212	case NS_SUCCESS:
1213		error = 0;
1214		for (cur = result; cur; cur = cur->ai_next) {
1215			/* Check for already filled port. */
1216			if (*getport(cur))
1217				continue;
1218			GET_PORT(cur, servname, svd);
1219			/* canonname should be filled already */
1220		}
1221		break;
1222	}
1223
1224	*res = result;
1225
1226	return 0;
1227
1228free:
1229	if (result)
1230		freeaddrinfo(result);
1231	return error;
1232}
1233
1234/*
1235 * hostname == NULL.
1236 * passive socket -> anyaddr (0.0.0.0 or ::)
1237 * non-passive socket -> localhost (127.0.0.1 or ::1)
1238 */
1239static int
1240explore_null(const struct addrinfo *pai, const char *servname,
1241    struct addrinfo **res, struct servent_data *svd)
1242{
1243	int s;
1244	const struct afd *afd;
1245	struct addrinfo *cur;
1246	struct addrinfo sentinel;
1247	int error;
1248
1249	_DIAGASSERT(pai != NULL);
1250	/* servname may be NULL */
1251	_DIAGASSERT(res != NULL);
1252
1253	*res = NULL;
1254	sentinel.ai_next = NULL;
1255	cur = &sentinel;
1256
1257	/*
1258	 * filter out AFs that are not supported by the kernel
1259	 * XXX errno?
1260	 */
1261	s = socket(pai->ai_family, SOCK_DGRAM, 0);
1262	if (s < 0) {
1263		if (errno != EMFILE)
1264			return 0;
1265	} else
1266		close(s);
1267
1268	/*
1269	 * if the servname does not match socktype/protocol, ignore it.
1270	 */
1271	if (get_portmatch(pai, servname, svd) != 0)
1272		return 0;
1273
1274	afd = find_afd(pai->ai_family);
1275	if (afd == NULL)
1276		return 0;
1277
1278	if (pai->ai_flags & AI_PASSIVE) {
1279		GET_AI(cur->ai_next, afd, afd->a_addrany);
1280		/* xxx meaningless?
1281		 * GET_CANONNAME(cur->ai_next, "anyaddr");
1282		 */
1283		GET_PORT(cur->ai_next, servname, svd);
1284	} else {
1285		GET_AI(cur->ai_next, afd, afd->a_loopback);
1286		/* xxx meaningless?
1287		 * GET_CANONNAME(cur->ai_next, "localhost");
1288		 */
1289		GET_PORT(cur->ai_next, servname, svd);
1290	}
1291	cur = cur->ai_next;
1292
1293	*res = sentinel.ai_next;
1294	return 0;
1295
1296free:
1297	if (sentinel.ai_next)
1298		freeaddrinfo(sentinel.ai_next);
1299	return error;
1300}
1301
1302/*
1303 * numeric hostname
1304 */
1305static int
1306explore_numeric(const struct addrinfo *pai, const char *hostname,
1307    const char *servname, struct addrinfo **res, const char *canonname,
1308    struct servent_data *svd)
1309{
1310	const struct afd *afd;
1311	struct addrinfo *cur;
1312	struct addrinfo sentinel;
1313	int error;
1314	char pton[PTON_MAX];
1315
1316	_DIAGASSERT(pai != NULL);
1317	/* hostname may be NULL */
1318	/* servname may be NULL */
1319	_DIAGASSERT(res != NULL);
1320
1321	*res = NULL;
1322	sentinel.ai_next = NULL;
1323	cur = &sentinel;
1324
1325	/*
1326	 * if the servname does not match socktype/protocol, ignore it.
1327	 */
1328	if (get_portmatch(pai, servname, svd) != 0)
1329		return 0;
1330
1331	afd = find_afd(pai->ai_family);
1332	if (afd == NULL)
1333		return 0;
1334
1335	switch (afd->a_af) {
1336	case AF_INET:
1337	       /*
1338		* RFC3493 section 6.1, requires getaddrinfo() to accept
1339		* AF_INET formats that are accepted by inet_addr(); here
1340		* we use the equivalent inet_aton() function so we can
1341		* check for errors. inet_pton() only accepts addresses
1342		* in the dotted quad format and only in base 10, so we
1343		* need to treat AF_INET specially.
1344		*
1345		* We also check for trailing characters and fail if there
1346		* are any. This matches the inet_pton6(), but not the
1347		* inet_pton4() behavior. We choose to make the protocol
1348		* behavior consistent.
1349		*/
1350		if (inet_aton(hostname, (void *)pton) == 1 &&
1351		    hostname[strspn(hostname, "0123456789.xabcdefXABCDEF")]
1352		    == '\0') {
1353			if (pai->ai_family == afd->a_af ||
1354			    pai->ai_family == PF_UNSPEC /*?*/) {
1355				GET_AI(cur->ai_next, afd, pton);
1356				GET_PORT(cur->ai_next, servname, svd);
1357				if ((pai->ai_flags & AI_CANONNAME)) {
1358					/*
1359					 * Set the numeric address itself as
1360					 * the canonical name, based on a
1361					 * clarification in rfc2553bis-03.
1362					 */
1363					GET_CANONNAME(cur->ai_next, canonname);
1364				}
1365				while (cur && cur->ai_next)
1366					cur = cur->ai_next;
1367			} else
1368				ERR(EAI_FAMILY);	/*xxx*/
1369		}
1370		break;
1371	default:
1372		if (inet_pton(afd->a_af, hostname, pton) == 1) {
1373			if (pai->ai_family == afd->a_af ||
1374			    pai->ai_family == PF_UNSPEC /*?*/) {
1375				GET_AI(cur->ai_next, afd, pton);
1376				GET_PORT(cur->ai_next, servname, svd);
1377				if ((pai->ai_flags & AI_CANONNAME)) {
1378					/*
1379					 * Set the numeric address itself as
1380					 * the canonical name, based on a
1381					 * clarification in rfc2553bis-03.
1382					 */
1383					GET_CANONNAME(cur->ai_next, canonname);
1384				}
1385				while (cur->ai_next)
1386					cur = cur->ai_next;
1387			} else
1388				ERR(EAI_FAMILY);	/*xxx*/
1389		}
1390		break;
1391	}
1392
1393	*res = sentinel.ai_next;
1394	return 0;
1395
1396free:
1397bad:
1398	if (sentinel.ai_next)
1399		freeaddrinfo(sentinel.ai_next);
1400	return error;
1401}
1402
1403/*
1404 * numeric hostname with scope
1405 */
1406static int
1407explore_numeric_scope(const struct addrinfo *pai, const char *hostname,
1408    const char *servname, struct addrinfo **res, struct servent_data *svd)
1409{
1410#if !defined(SCOPE_DELIMITER) || !defined(INET6)
1411	return explore_numeric(pai, hostname, servname, res, hostname, svd);
1412#else
1413	const struct afd *afd;
1414	struct addrinfo *cur;
1415	int error;
1416	char *cp, *hostname2 = NULL, *scope, *addr;
1417	struct sockaddr_in6 *sin6;
1418
1419	_DIAGASSERT(pai != NULL);
1420	/* hostname may be NULL */
1421	/* servname may be NULL */
1422	_DIAGASSERT(res != NULL);
1423
1424	/*
1425	 * if the servname does not match socktype/protocol, ignore it.
1426	 */
1427	if (get_portmatch(pai, servname, svd) != 0)
1428		return 0;
1429
1430	afd = find_afd(pai->ai_family);
1431	if (afd == NULL)
1432		return 0;
1433
1434	if (!afd->a_scoped)
1435		return explore_numeric(pai, hostname, servname, res, hostname,
1436		    svd);
1437
1438	cp = strchr(hostname, SCOPE_DELIMITER);
1439	if (cp == NULL)
1440		return explore_numeric(pai, hostname, servname, res, hostname,
1441		    svd);
1442
1443	/*
1444	 * Handle special case of <scoped_address><delimiter><scope id>
1445	 */
1446	hostname2 = strdup(hostname);
1447	if (hostname2 == NULL)
1448		return EAI_MEMORY;
1449	/* terminate at the delimiter */
1450	hostname2[cp - hostname] = '\0';
1451	addr = hostname2;
1452	scope = cp + 1;
1453
1454	error = explore_numeric(pai, addr, servname, res, hostname, svd);
1455	if (error == 0) {
1456		u_int32_t scopeid;
1457
1458		for (cur = *res; cur; cur = cur->ai_next) {
1459			if (cur->ai_family != AF_INET6)
1460				continue;
1461			sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
1462			if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) {
1463				free(hostname2);
1464				return EAI_NODATA; /* XXX: is return OK? */
1465			}
1466			sin6->sin6_scope_id = scopeid;
1467		}
1468	}
1469
1470	free(hostname2);
1471
1472	return error;
1473#endif
1474}
1475
1476static int
1477get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str)
1478{
1479
1480	_DIAGASSERT(pai != NULL);
1481	_DIAGASSERT(ai != NULL);
1482	_DIAGASSERT(str != NULL);
1483
1484	if ((pai->ai_flags & AI_CANONNAME) != 0) {
1485		ai->ai_canonname = strdup(str);
1486		if (ai->ai_canonname == NULL)
1487			return EAI_MEMORY;
1488	}
1489	return 0;
1490}
1491
1492struct addrinfo *
1493allocaddrinfo(socklen_t addrlen)
1494{
1495	struct addrinfo *ai;
1496
1497	ai = calloc(sizeof(struct addrinfo) + addrlen, 1);
1498	if (ai) {
1499		ai->ai_addr = (void *)(ai+1);
1500		ai->ai_addrlen = ai->ai_addr->sa_len = addrlen;
1501	}
1502
1503	return ai;
1504}
1505
1506static struct addrinfo *
1507get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr)
1508{
1509	char *p;
1510	struct addrinfo *ai;
1511	struct sockaddr *save;
1512
1513	_DIAGASSERT(pai != NULL);
1514	_DIAGASSERT(afd != NULL);
1515	_DIAGASSERT(addr != NULL);
1516
1517	ai = allocaddrinfo((socklen_t)afd->a_socklen);
1518	if (ai == NULL)
1519		return NULL;
1520
1521	save = ai->ai_addr;
1522	memcpy(ai, pai, sizeof(struct addrinfo));
1523
1524	/* since we just overwrote all of ai, we have
1525	   to restore ai_addr and ai_addrlen */
1526	ai->ai_addr = save;
1527	ai->ai_addrlen = (socklen_t)afd->a_socklen;
1528
1529	ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
1530	p = (char *)(void *)(ai->ai_addr);
1531	memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen);
1532	return ai;
1533}
1534
1535static int
1536get_portmatch(const struct addrinfo *ai, const char *servname,
1537    struct servent_data *svd)
1538{
1539
1540	_DIAGASSERT(ai != NULL);
1541	/* servname may be NULL */
1542
1543	return get_port(ai, servname, 1, svd);
1544}
1545
1546static int
1547get_port(const struct addrinfo *ai, const char *servname, int matchonly,
1548    struct servent_data *svd)
1549{
1550	const char *proto;
1551	struct servent *sp;
1552	int port;
1553	int allownumeric;
1554
1555	_DIAGASSERT(ai != NULL);
1556	/* servname may be NULL */
1557
1558	if (servname == NULL)
1559		return 0;
1560	switch (ai->ai_family) {
1561	case AF_INET:
1562#ifdef AF_INET6
1563	case AF_INET6:
1564#endif
1565		break;
1566	default:
1567		return 0;
1568	}
1569
1570	switch (ai->ai_socktype) {
1571	case SOCK_RAW:
1572		return EAI_SERVICE;
1573	case SOCK_DGRAM:
1574	case SOCK_STREAM:
1575		allownumeric = 1;
1576		break;
1577	case ANY:
1578		/*
1579		 * This was 0.	It is now 1 so that queries specifying
1580		 * a NULL hint, or hint without socktype (but, hopefully,
1581		 * with protocol) and numeric address actually work.
1582		 */
1583		allownumeric = 1;
1584		break;
1585	default:
1586		return EAI_SOCKTYPE;
1587	}
1588
1589	port = str2number(servname);
1590	if (port >= 0) {
1591		if (!allownumeric)
1592			return EAI_SERVICE;
1593		if (port < 0 || port > 65535)
1594			return EAI_SERVICE;
1595		port = htons(port);
1596	} else {
1597		struct servent sv;
1598		if (ai->ai_flags & AI_NUMERICSERV)
1599			return EAI_NONAME;
1600
1601		switch (ai->ai_socktype) {
1602		case SOCK_DGRAM:
1603			proto = "udp";
1604			break;
1605		case SOCK_STREAM:
1606			proto = "tcp";
1607			break;
1608		default:
1609			proto = NULL;
1610			break;
1611		}
1612
1613		sp = getservbyname_r(servname, proto, &sv, svd);
1614		if (sp == NULL)
1615			return EAI_SERVICE;
1616		port = sp->s_port;
1617	}
1618
1619	if (!matchonly)
1620		*getport(__DECONST(struct addrinfo*, ai)) = port;
1621	return 0;
1622}
1623
1624static const struct afd *
1625find_afd(int af)
1626{
1627	const struct afd *afd;
1628
1629	if (af == PF_UNSPEC)
1630		return NULL;
1631	for (afd = afdl; afd->a_af; afd++) {
1632		if (afd->a_af == af)
1633			return afd;
1634	}
1635	return NULL;
1636}
1637
1638/*
1639 * AI_ADDRCONFIG check: Build a mask containing a bit set for each address
1640 * family configured in the system.
1641 *
1642 */
1643static int
1644addrconfig(uint64_t *mask)
1645{
1646	struct ifaddrs *ifaddrs, *ifa;
1647
1648	if (getifaddrs(&ifaddrs) == -1)
1649		return -1;
1650
1651	*mask = 0;
1652	for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next)
1653#ifndef __HAIKU__
1654		if (ifa->ifa_addr && (ifa->ifa_flags & IFF_UP)) {
1655#else
1656 		if (ifa->ifa_addr && (ifa->ifa_flags & IFF_UP)
1657 				&& !(ifa->ifa_flags & IFF_LOOPBACK)) {
1658			assert(ifa->ifa_addr->sa_family < 64);
1659#endif
1660			*mask |= (uint64_t)1 << ifa->ifa_addr->sa_family;
1661		}
1662
1663	freeifaddrs(ifaddrs);
1664	return 0;
1665}
1666
1667#ifdef INET6
1668/* convert a string to a scope identifier. XXX: IPv6 specific */
1669static int
1670ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid)
1671{
1672	u_long lscopeid;
1673	struct in6_addr *a6;
1674	char *ep;
1675
1676	_DIAGASSERT(scope != NULL);
1677	_DIAGASSERT(sin6 != NULL);
1678	_DIAGASSERT(scopeid != NULL);
1679
1680	a6 = &sin6->sin6_addr;
1681
1682	/* empty scopeid portion is invalid */
1683	if (*scope == '\0')
1684		return -1;
1685
1686	if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) {
1687		/*
1688		 * We currently assume a one-to-one mapping between links
1689		 * and interfaces, so we simply use interface indices for
1690		 * like-local scopes.
1691		 */
1692		*scopeid = if_nametoindex(scope);
1693		if (*scopeid == 0)
1694			goto trynumeric;
1695		return 0;
1696	}
1697
1698	/* still unclear about literal, allow numeric only - placeholder */
1699	if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
1700		goto trynumeric;
1701	if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
1702		goto trynumeric;
1703	else
1704		goto trynumeric;	/* global */
1705
1706	/* try to convert to a numeric id as a last resort */
1707  trynumeric:
1708	errno = 0;
1709	lscopeid = strtoul(scope, &ep, 10);
1710	*scopeid = (u_int32_t)(lscopeid & 0xffffffffUL);
1711	if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid)
1712		return 0;
1713	else
1714		return -1;
1715}
1716#endif
1717
1718/* code duplicate with gethnamaddr.c */
1719
1720static const char AskedForGot[] =
1721	"gethostby*.getanswer: asked for \"%s\", got \"%s\"";
1722
1723#define maybe_ok(res, nm, ok) (((res)->options & RES_NOCHECKNAME) != 0U || \
1724                               (ok)(nm) != 0)
1725static struct addrinfo *
1726getanswer(res_state res, const querybuf *answer, int anslen, const char *qname,
1727    int qtype, const struct addrinfo *pai)
1728{
1729	struct addrinfo sentinel, *cur;
1730	struct addrinfo ai, *aip;
1731	const struct afd *afd;
1732	char *canonname;
1733	const HEADER *hp;
1734	const u_char *cp;
1735	int n;
1736	const u_char *eom;
1737	char *bp, *ep;
1738	int type, class, ancount, qdcount;
1739	int haveanswer, had_error;
1740	char tbuf[MAXDNAME];
1741	int (*name_ok) (const char *);
1742	char hostbuf[8*1024];
1743	int port, pri, weight;
1744	struct srvinfo *srvlist, *srv, *csrv;
1745
1746	_DIAGASSERT(answer != NULL);
1747	_DIAGASSERT(qname != NULL);
1748	_DIAGASSERT(pai != NULL);
1749	_DIAGASSERT(res != NULL);
1750
1751	memset(&sentinel, 0, sizeof(sentinel));
1752	cur = &sentinel;
1753
1754	canonname = NULL;
1755	eom = answer->buf + anslen;
1756	switch (qtype) {
1757	case T_A:
1758	case T_AAAA:
1759	case T_ANY:	/*use T_ANY only for T_A/T_AAAA lookup*/
1760		name_ok = res_hnok;
1761		break;
1762	case T_SRV:
1763		name_ok = gai_srvok;
1764		break;
1765	default:
1766		return NULL;	/* XXX should be abort(); */
1767	}
1768	/*
1769	 * find first satisfactory answer
1770	 */
1771	hp = &answer->hdr;
1772	ancount = ntohs(hp->ancount);
1773	qdcount = ntohs(hp->qdcount);
1774	bp = hostbuf;
1775	ep = hostbuf + sizeof hostbuf;
1776	cp = answer->buf + HFIXEDSZ;
1777	if (qdcount != 1) {
1778		h_errno = NO_RECOVERY;
1779		return NULL;
1780	}
1781	n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp));
1782	if ((n < 0) || !maybe_ok(res, bp, name_ok)) {
1783		h_errno = NO_RECOVERY;
1784		return NULL;
1785	}
1786	cp += n + QFIXEDSZ;
1787	if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
1788		/* res_send() has already verified that the query name is the
1789		 * same as the one we sent; this just gets the expanded name
1790		 * (i.e., with the succeeding search-domain tacked on).
1791		 */
1792		n = (int)strlen(bp) + 1;		/* for the \0 */
1793		if (n >= MAXHOSTNAMELEN) {
1794			h_errno = NO_RECOVERY;
1795			return NULL;
1796		}
1797		canonname = bp;
1798		bp += n;
1799		/* The qname can be abbreviated, but h_name is now absolute. */
1800		qname = canonname;
1801	}
1802	haveanswer = 0;
1803	had_error = 0;
1804	srvlist = NULL;
1805	while (ancount-- > 0 && cp < eom && !had_error) {
1806		n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp));
1807		if ((n < 0) || !maybe_ok(res, bp, name_ok)) {
1808			had_error++;
1809			continue;
1810		}
1811		cp += n;			/* name */
1812		type = _getshort(cp);
1813		cp += INT16SZ;			/* type */
1814		class = _getshort(cp);
1815		cp += INT16SZ + INT32SZ;	/* class, TTL */
1816		n = _getshort(cp);
1817		cp += INT16SZ;			/* len */
1818		if (class != C_IN) {
1819			/* XXX - debug? syslog? */
1820			cp += n;
1821			continue;		/* XXX - had_error++ ? */
1822		}
1823		if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
1824		    type == T_CNAME) {
1825			n = dn_expand(answer->buf, eom, cp, tbuf, (int)sizeof tbuf);
1826			if ((n < 0) || !maybe_ok(res, tbuf, name_ok)) {
1827				had_error++;
1828				continue;
1829			}
1830			cp += n;
1831			/* Get canonical name. */
1832			n = (int)strlen(tbuf) + 1;	/* for the \0 */
1833			if (n > ep - bp || n >= MAXHOSTNAMELEN) {
1834				had_error++;
1835				continue;
1836			}
1837			strlcpy(bp, tbuf, (size_t)(ep - bp));
1838			canonname = bp;
1839			bp += n;
1840			continue;
1841		}
1842		if (qtype == T_ANY) {
1843			if (!(type == T_A || type == T_AAAA)) {
1844				cp += n;
1845				continue;
1846			}
1847		} else if (type != qtype) {
1848			if (type != T_KEY && type != T_SIG) {
1849				syslog(LOG_NOTICE|LOG_AUTH,
1850	       "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
1851				       qname, p_class(C_IN), p_type(qtype),
1852				       p_type(type));
1853			}
1854			cp += n;
1855			continue;		/* XXX - had_error++ ? */
1856		}
1857		switch (type) {
1858		case T_A:
1859		case T_AAAA:
1860			if (strcasecmp(canonname, bp) != 0) {
1861				syslog(LOG_NOTICE|LOG_AUTH,
1862				       AskedForGot, canonname, bp);
1863				cp += n;
1864				continue;	/* XXX - had_error++ ? */
1865			}
1866			if (type == T_A && n != INADDRSZ) {
1867				cp += n;
1868				continue;
1869			}
1870			if (type == T_AAAA && n != IN6ADDRSZ) {
1871				cp += n;
1872				continue;
1873			}
1874			if (type == T_AAAA) {
1875				struct in6_addr in6;
1876				memcpy(&in6, cp, IN6ADDRSZ);
1877				if (IN6_IS_ADDR_V4MAPPED(&in6)) {
1878					cp += n;
1879					continue;
1880				}
1881			}
1882			if (!haveanswer) {
1883				int nn;
1884
1885				canonname = bp;
1886				nn = (int)strlen(bp) + 1;	/* for the \0 */
1887				bp += nn;
1888			}
1889
1890			/* don't overwrite pai */
1891			ai = *pai;
1892			ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
1893			afd = find_afd(ai.ai_family);
1894			if (afd == NULL) {
1895				cp += n;
1896				continue;
1897			}
1898			cur->ai_next = get_ai(&ai, afd, (const char *)cp);
1899			if (cur->ai_next == NULL)
1900				had_error++;
1901			while (cur && cur->ai_next)
1902				cur = cur->ai_next;
1903			cp += n;
1904			break;
1905		case T_SRV:
1906			/* Add to SRV list. Insertion sort on priority. */
1907			pri = _getshort(cp);
1908			cp += INT16SZ;
1909			weight = _getshort(cp);
1910			cp += INT16SZ;
1911			port = _getshort(cp);
1912			cp += INT16SZ;
1913			n = dn_expand(answer->buf, eom, cp, tbuf,
1914			    (int)sizeof(tbuf));
1915			if ((n < 0) || !maybe_ok(res, tbuf, res_hnok)) {
1916				had_error++;
1917				continue;
1918			}
1919			cp += n;
1920			if (strlen(tbuf) + 1 >= MAXDNAME) {
1921				had_error++;
1922				continue;
1923			}
1924			srv = malloc(sizeof(*srv));
1925			if (!srv) {
1926				had_error++;
1927				continue;
1928			}
1929			strlcpy(srv->name, tbuf, sizeof(srv->name));
1930			srv->pri = pri;
1931			srv->weight = weight;
1932			srv->port = port;
1933			/* Weight 0 is sorted before other weights. */
1934			if (!srvlist
1935			    || srv->pri < srvlist->pri
1936			    || (srv->pri == srvlist->pri &&
1937			    (!srv->weight || srvlist->weight))) {
1938				srv->next = srvlist;
1939				srvlist = srv;
1940			} else {
1941				for (csrv = srvlist;
1942				    csrv->next && csrv->next->pri <= srv->pri;
1943				    csrv = csrv->next) {
1944					if (csrv->next->pri == srv->pri
1945					    && (!srv->weight ||
1946					    csrv->next->weight))
1947						break;
1948				}
1949				srv->next = csrv->next;
1950				csrv->next = srv;
1951			}
1952			continue; /* Don't add to haveanswer yet. */
1953		default:
1954			abort();
1955		}
1956		if (!had_error)
1957			haveanswer++;
1958	}
1959
1960	if (srvlist) {
1961		/*
1962		 * Check for explicit rejection.
1963		 */
1964		if (!srvlist->next && !srvlist->name[0]) {
1965			free(srvlist);
1966			h_errno = HOST_NOT_FOUND;
1967			return NULL;
1968		}
1969
1970		while (srvlist) {
1971			struct res_target q, q2;
1972
1973			srv = srvlist;
1974			srvlist = srvlist->next;
1975
1976			/*
1977			 * Since res_* doesn't give the additional
1978			 * section, we always look up.
1979			 */
1980			memset(&q, 0, sizeof(q));
1981			memset(&q2, 0, sizeof(q2));
1982
1983			q.name = srv->name;
1984			q.qclass = C_IN;
1985			q.qtype = T_AAAA;
1986			q.next = &q2;
1987			q2.name = srv->name;
1988			q2.qclass = C_IN;
1989			q2.qtype = T_A;
1990
1991			aip = _dns_query(&q, pai, res, 0);
1992
1993			if (aip != NULL) {
1994				cur->ai_next = aip;
1995				while (cur && cur->ai_next) {
1996					cur = cur->ai_next;
1997					*getport(cur) = htons(srv->port);
1998					haveanswer++;
1999				}
2000			}
2001			free(srv);
2002		}
2003	}
2004	if (haveanswer) {
2005		if (!sentinel.ai_next->ai_canonname)
2006		       (void)get_canonname(pai, sentinel.ai_next,
2007			   canonname ? canonname : qname);
2008		h_errno = NETDB_SUCCESS;
2009		return sentinel.ai_next;
2010	}
2011
2012	/* We could have walked a CNAME chain, */
2013	/* but the ultimate target may not have what we looked for */
2014	h_errno = ntohs(hp->ancount) > 0? NO_DATA : NO_RECOVERY;
2015	return NULL;
2016}
2017
2018#define SORTEDADDR(p)	(((struct sockaddr_in *)(void *)(p->ai_next->ai_addr))->sin_addr.s_addr)
2019#define SORTMATCH(p, s) ((SORTEDADDR(p) & (s).mask) == (s).addr.s_addr)
2020
2021static void
2022aisort(struct addrinfo *s, res_state res)
2023{
2024	struct addrinfo head, *t, *p;
2025	int i;
2026
2027	head.ai_next = NULL;
2028	t = &head;
2029
2030	for (i = 0; i < res->nsort; i++) {
2031		p = s;
2032		while (p->ai_next) {
2033			if ((p->ai_next->ai_family != AF_INET)
2034			|| SORTMATCH(p, res->sort_list[i])) {
2035				t->ai_next = p->ai_next;
2036				t = t->ai_next;
2037				p->ai_next = p->ai_next->ai_next;
2038			} else {
2039				p = p->ai_next;
2040			}
2041		}
2042	}
2043
2044	/* add rest of list and reset s to the new list*/
2045	t->ai_next = s->ai_next;
2046	s->ai_next = head.ai_next;
2047}
2048
2049static struct addrinfo *
2050_dns_query(struct res_target *q, const struct addrinfo *pai,
2051    res_state res, int dosearch)
2052{
2053	struct res_target *q2 = q->next;
2054 	querybuf *buf, *buf2;
2055	struct addrinfo sentinel, *cur, *ai;
2056
2057#ifdef DNS_DEBUG
2058	struct res_target *iter;
2059	for (iter = q; iter; iter = iter->next)
2060		printf("Query type %d for %s\n", iter->qtype, iter->name);
2061#endif
2062
2063 	buf = malloc(sizeof(*buf));
2064 	if (buf == NULL) {
2065 		h_errno = NETDB_INTERNAL;
2066		return NULL;
2067 	}
2068 	buf2 = malloc(sizeof(*buf2));
2069 	if (buf2 == NULL) {
2070 		free(buf);
2071 		h_errno = NETDB_INTERNAL;
2072		return NULL;
2073	}
2074
2075	memset(&sentinel, 0, sizeof(sentinel));
2076	cur = &sentinel;
2077
2078	q->answer = buf->buf;
2079	q->anslen = sizeof(buf->buf);
2080	if (q2) {
2081		q2->answer = buf2->buf;
2082		q2->anslen = sizeof(buf2->buf);
2083	}
2084
2085	if (dosearch) {
2086		if (res_searchN(q->name, q, res) < 0)
2087			goto out;
2088	} else {
2089		if (res_queryN(q->name, q, res) < 0)
2090			goto out;
2091	}
2092
2093	ai = getanswer(res, buf, q->n, q->name, q->qtype, pai);
2094	if (ai) {
2095		cur->ai_next = ai;
2096		while (cur && cur->ai_next)
2097			cur = cur->ai_next;
2098	}
2099	if (q2) {
2100		ai = getanswer(res, buf2, q2->n, q2->name, q2->qtype, pai);
2101		if (ai)
2102			cur->ai_next = ai;
2103 	}
2104	free(buf);
2105	free(buf2);
2106	return sentinel.ai_next;
2107out:
2108	free(buf);
2109	free(buf2);
2110	return NULL;
2111}
2112
2113/*ARGSUSED*/
2114static struct addrinfo *
2115_dns_srv_lookup(const char *name, const char *servname,
2116    const struct addrinfo *pai)
2117{
2118	static const char * const srvprotos[] = { "tcp", "udp" };
2119	static const int srvnottype[] = { SOCK_DGRAM, SOCK_STREAM };
2120	static const int nsrvprotos = 2;
2121	struct addrinfo sentinel, *cur, *ai;
2122	struct servent *serv, sv;
2123	struct servent_data svd;
2124	struct res_target q;
2125	res_state res;
2126	char *tname;
2127	int i;
2128
2129	res = __res_get_state();
2130	if (res == NULL)
2131		return NULL;
2132
2133	memset(&svd, 0, sizeof(svd));
2134	memset(&sentinel, 0, sizeof(sentinel));
2135	cur = &sentinel;
2136
2137	/*
2138	 * Iterate over supported SRV protocols.
2139	 * (currently UDP and TCP only)
2140	 */
2141	for (i = 0; i < nsrvprotos; i++) {
2142		/*
2143		 * Check that the caller didn't specify a hint
2144		 * which precludes this protocol.
2145		 */
2146		if (pai->ai_socktype == srvnottype[i])
2147			continue;
2148		/*
2149		 * If the caller specified a port,
2150		 * then lookup the database for the
2151		 * official service name.
2152		 */
2153		serv = getservbyname_r(servname, srvprotos[i], &sv, &svd);
2154		if (serv == NULL)
2155			continue;
2156
2157		/*
2158		 * Construct service DNS name.
2159		 */
2160		if (asprintf(&tname, "_%s._%s.%s", serv->s_name, serv->s_proto,
2161		    name) < 0)
2162			continue;
2163
2164		memset(&q, 0, sizeof(q));
2165		q.name = tname;
2166		q.qclass = C_IN;
2167		q.qtype = T_SRV;
2168
2169		/*
2170		 * Do SRV query.
2171		 */
2172		ai = _dns_query(&q, pai, res, 1);
2173		if (ai) {
2174			cur->ai_next = ai;
2175			while (cur && cur->ai_next)
2176				cur = cur->ai_next;
2177		}
2178		free(tname);
2179	}
2180
2181	if (res->nsort)
2182		aisort(&sentinel, res);
2183
2184	__res_put_state(res);
2185
2186	return sentinel.ai_next;
2187}
2188
2189/*ARGSUSED*/
2190static struct addrinfo *
2191_dns_host_lookup(const char *name, const struct addrinfo *pai)
2192{
2193	struct res_target q, q2;
2194	struct addrinfo sentinel, *ai;
2195	res_state res;
2196
2197	res = __res_get_state();
2198	if (res == NULL)
2199		return NULL;
2200
2201	memset(&q, 0, sizeof(q2));
2202	memset(&q2, 0, sizeof(q2));
2203
2204	switch (pai->ai_family) {
2205	case AF_UNSPEC:
2206		/* prefer IPv6 */
2207		q.name = name;
2208		q.qclass = C_IN;
2209		q.qtype = T_AAAA;
2210		q.next = &q2;
2211		q2.name = name;
2212		q2.qclass = C_IN;
2213		q2.qtype = T_A;
2214		break;
2215	case AF_INET:
2216		q.name = name;
2217		q.qclass = C_IN;
2218		q.qtype = T_A;
2219		break;
2220	case AF_INET6:
2221		q.name = name;
2222		q.qclass = C_IN;
2223		q.qtype = T_AAAA;
2224		break;
2225	default:
2226		__res_put_state(res);
2227		h_errno = NETDB_INTERNAL;
2228		return NULL;
2229	}
2230
2231	ai = _dns_query(&q, pai, res, 1);
2232
2233	memset(&sentinel, 0, sizeof(sentinel));
2234	sentinel.ai_next = ai;
2235
2236	if (ai != NULL && res->nsort)
2237		aisort(&sentinel, res);
2238
2239	__res_put_state(res);
2240
2241	return sentinel.ai_next;
2242}
2243
2244/*ARGSUSED*/
2245static int
2246_dns_getaddrinfo(void *rv, void *cb_data, va_list ap)
2247{
2248	struct addrinfo *ai = NULL;
2249	const char *name, *servname;
2250	const struct addrinfo *pai;
2251
2252	name = va_arg(ap, char *);
2253	pai = va_arg(ap, const struct addrinfo *);
2254	servname = va_arg(ap, char *);
2255
2256	/*
2257	 * Try doing SRV lookup on service first.
2258	 */
2259	if (servname
2260#ifdef AI_SRV
2261	    && (pai->ai_flags & AI_SRV)
2262#endif
2263	    && !(pai->ai_flags & AI_NUMERICSERV)
2264	    && str2number(servname) == -1) {
2265
2266#ifdef DNS_DEBUG
2267		printf("%s: try SRV lookup\n", __func__);
2268#endif
2269		ai = _dns_srv_lookup(name, servname, pai);
2270	}
2271
2272	/*
2273	 * Do lookup on name.
2274	 */
2275	if (ai == NULL) {
2276
2277#ifdef DNS_DEBUG
2278		printf("%s: try HOST lookup\n", __func__);
2279#endif
2280		ai = _dns_host_lookup(name, pai);
2281
2282		if (ai == NULL) {
2283			switch (h_errno) {
2284			case HOST_NOT_FOUND:
2285			case NO_DATA:	// XXX: Perhaps we could differentiate
2286					// So that we could return EAI_NODATA?
2287				return NS_NOTFOUND;
2288			case TRY_AGAIN:
2289				return NS_TRYAGAIN;
2290			default:
2291				return NS_UNAVAIL;
2292			}
2293		}
2294	}
2295
2296	*((struct addrinfo **)rv) = ai;
2297	return NS_SUCCESS;
2298}
2299
2300static void
2301_sethtent(FILE **hostf)
2302{
2303
2304	if (!*hostf) {
2305		char buffer[256];
2306		find_directory(B_SYSTEM_SETTINGS_DIRECTORY, 0, false, buffer, sizeof(buffer));
2307		strlcat(buffer, "/network/hosts", sizeof(buffer));
2308
2309		*hostf = fopen(buffer, "re");
2310	} else
2311		rewind(*hostf);
2312}
2313
2314static void
2315_endhtent(FILE **hostf)
2316{
2317
2318	if (*hostf) {
2319		(void) fclose(*hostf);
2320		*hostf = NULL;
2321	}
2322}
2323
2324static struct addrinfo *
2325_gethtent(FILE **hostf, const char *name, const struct addrinfo *pai)
2326{
2327	char *p;
2328	char *cp, *tname, *cname;
2329	struct addrinfo hints, *res0, *res;
2330	int error;
2331	const char *addr;
2332	char hostbuf[8*1024];
2333
2334	assert(name != NULL);
2335	assert(pai != NULL);
2336
2337	if (!*hostf)
2338		_sethtent(hostf);
2339	if (!*hostf)
2340		return (NULL);
2341 again:
2342	if (!(p = fgets(hostbuf, (int)sizeof hostbuf, *hostf)))
2343		return NULL;
2344	if (*p == '#')
2345		goto again;
2346	if (!(cp = strpbrk(p, "#\n")))
2347		goto again;
2348	*cp = '\0';
2349	if (!(cp = strpbrk(p, " \t")))
2350		goto again;
2351	*cp++ = '\0';
2352	addr = p;
2353	/* if this is not something we're looking for, skip it. */
2354	cname = NULL;
2355	while (cp && *cp) {
2356		if (*cp == ' ' || *cp == '\t') {
2357			cp++;
2358			continue;
2359		}
2360		if (!cname)
2361			cname = cp;
2362		tname = cp;
2363		if ((cp = strpbrk(cp, " \t")) != NULL)
2364			*cp++ = '\0';
2365		if (strcasecmp(name, tname) == 0)
2366			goto found;
2367	}
2368	goto again;
2369
2370found:
2371	hints = *pai;
2372	hints.ai_flags = AI_NUMERICHOST;
2373	error = getaddrinfo(addr, NULL, &hints, &res0);
2374	if (error)
2375		goto again;
2376	for (res = res0; res; res = res->ai_next) {
2377		/* cover it up */
2378		res->ai_flags = pai->ai_flags;
2379
2380		if (pai->ai_flags & AI_CANONNAME) {
2381			if (get_canonname(pai, res, cname) != 0) {
2382				freeaddrinfo(res0);
2383				goto again;
2384			}
2385		}
2386	}
2387	return res0;
2388}
2389
2390/*ARGSUSED*/
2391static int
2392_files_getaddrinfo(void *rv, void *cb_data, va_list ap)
2393{
2394	const char *name;
2395	const struct addrinfo *pai;
2396	struct addrinfo sentinel, *cur;
2397	struct addrinfo *p;
2398#ifndef _REENTRANT
2399	static
2400#endif
2401	FILE *hostf = NULL;
2402
2403	name = va_arg(ap, char *);
2404	pai = va_arg(ap, const struct addrinfo *);
2405
2406	memset(&sentinel, 0, sizeof(sentinel));
2407	cur = &sentinel;
2408
2409	_sethtent(&hostf);
2410	while ((p = _gethtent(&hostf, name, pai)) != NULL) {
2411		cur->ai_next = p;
2412		while (cur && cur->ai_next)
2413			cur = cur->ai_next;
2414	}
2415	_endhtent(&hostf);
2416
2417	*((struct addrinfo **)rv) = sentinel.ai_next;
2418	if (sentinel.ai_next == NULL)
2419		return NS_NOTFOUND;
2420	return NS_SUCCESS;
2421}
2422
2423#ifdef YP
2424/*ARGSUSED*/
2425static struct addrinfo *
2426_yphostent(char *line, const struct addrinfo *pai)
2427{
2428	struct addrinfo sentinel, *cur;
2429	struct addrinfo hints, *res, *res0;
2430	int error;
2431	char *p;
2432	const char *addr, *canonname;
2433	char *nextline;
2434	char *cp;
2435
2436	_DIAGASSERT(line != NULL);
2437	_DIAGASSERT(pai != NULL);
2438
2439	p = line;
2440	addr = canonname = NULL;
2441
2442	memset(&sentinel, 0, sizeof(sentinel));
2443	cur = &sentinel;
2444
2445nextline:
2446	/* terminate line */
2447	cp = strchr(p, '\n');
2448	if (cp) {
2449		*cp++ = '\0';
2450		nextline = cp;
2451	} else
2452		nextline = NULL;
2453
2454	cp = strpbrk(p, " \t");
2455	if (cp == NULL) {
2456		if (canonname == NULL)
2457			return NULL;
2458		else
2459			goto done;
2460	}
2461	*cp++ = '\0';
2462
2463	addr = p;
2464
2465	while (cp && *cp) {
2466		if (*cp == ' ' || *cp == '\t') {
2467			cp++;
2468			continue;
2469		}
2470		if (!canonname)
2471			canonname = cp;
2472		if ((cp = strpbrk(cp, " \t")) != NULL)
2473			*cp++ = '\0';
2474	}
2475
2476	hints = *pai;
2477	hints.ai_flags = AI_NUMERICHOST;
2478	error = getaddrinfo(addr, NULL, &hints, &res0);
2479	if (error == 0) {
2480		for (res = res0; res; res = res->ai_next) {
2481			/* cover it up */
2482			res->ai_flags = pai->ai_flags;
2483
2484			if (pai->ai_flags & AI_CANONNAME)
2485				(void)get_canonname(pai, res, canonname);
2486		}
2487	} else
2488		res0 = NULL;
2489	if (res0) {
2490		cur->ai_next = res0;
2491		while (cur->ai_next)
2492			cur = cur->ai_next;
2493	}
2494
2495	if (nextline) {
2496		p = nextline;
2497		goto nextline;
2498	}
2499
2500done:
2501	return sentinel.ai_next;
2502}
2503
2504/*ARGSUSED*/
2505static int
2506_yp_getaddrinfo(void *rv, void *cb_data, va_list ap)
2507{
2508	struct addrinfo sentinel, *cur;
2509	struct addrinfo *ai = NULL;
2510	char *ypbuf;
2511	int ypbuflen, r;
2512	const char *name;
2513	const struct addrinfo *pai;
2514	char *ypdomain;
2515
2516	if (_yp_check(&ypdomain) == 0)
2517		return NS_UNAVAIL;
2518
2519	name = va_arg(ap, char *);
2520	pai = va_arg(ap, const struct addrinfo *);
2521
2522	memset(&sentinel, 0, sizeof(sentinel));
2523	cur = &sentinel;
2524
2525	/* hosts.byname is only for IPv4 (Solaris8) */
2526	if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) {
2527		r = yp_match(ypdomain, "hosts.byname", name,
2528			(int)strlen(name), &ypbuf, &ypbuflen);
2529		if (r == 0) {
2530			struct addrinfo ai4;
2531
2532			ai4 = *pai;
2533			ai4.ai_family = AF_INET;
2534			ai = _yphostent(ypbuf, &ai4);
2535			if (ai) {
2536				cur->ai_next = ai;
2537				while (cur && cur->ai_next)
2538					cur = cur->ai_next;
2539			}
2540		}
2541		free(ypbuf);
2542	}
2543
2544	/* ipnodes.byname can hold both IPv4/v6 */
2545	r = yp_match(ypdomain, "ipnodes.byname", name,
2546		(int)strlen(name), &ypbuf, &ypbuflen);
2547	if (r == 0) {
2548		ai = _yphostent(ypbuf, pai);
2549		if (ai)
2550			cur->ai_next = ai;
2551		free(ypbuf);
2552	}
2553
2554	if (sentinel.ai_next == NULL) {
2555		h_errno = HOST_NOT_FOUND;
2556		return NS_NOTFOUND;
2557	}
2558	*((struct addrinfo **)rv) = sentinel.ai_next;
2559	return NS_SUCCESS;
2560}
2561#endif
2562
2563/* resolver logic */
2564
2565/*
2566 * Formulate a normal query, send, and await answer.
2567 * Returned answer is placed in supplied buffer "answer".
2568 * Perform preliminary check of answer, returning success only
2569 * if no error is indicated and the answer count is nonzero.
2570 * Return the size of the response on success, -1 on error.
2571 * Error number is left in h_errno.
2572 *
2573 * Caller must parse answer and determine whether it answers the question.
2574 */
2575static int
2576res_queryN(const char *name, /* domain name */ struct res_target *target,
2577    res_state statp)
2578{
2579	u_char buf[MAXPACKET];
2580	HEADER *hp;
2581	int n;
2582	struct res_target *t;
2583	int rcode;
2584	u_char *rdata;
2585	int ancount;
2586
2587	_DIAGASSERT(name != NULL);
2588	/* XXX: target may be NULL??? */
2589
2590	rcode = NOERROR;
2591	ancount = 0;
2592
2593	for (t = target; t; t = t->next) {
2594		int class, type;
2595		u_char *answer;
2596		int anslen;
2597		u_int oflags;
2598
2599		hp = (HEADER *)(void *)t->answer;
2600		oflags = statp->_flags;
2601
2602again:
2603		hp->rcode = NOERROR;	/* default */
2604
2605		/* make it easier... */
2606		class = t->qclass;
2607		type = t->qtype;
2608		answer = t->answer;
2609		anslen = t->anslen;
2610#ifdef DEBUG
2611		if (statp->options & RES_DEBUG)
2612			printf(";; res_nquery(%s, %d, %d)\n", name, class, type);
2613#endif
2614
2615		n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL,
2616		    buf, (int)sizeof(buf));
2617#ifdef RES_USE_EDNS0
2618		if (n > 0 && (statp->_flags & RES_F_EDNS0ERR) == 0 &&
2619		    (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) {
2620			n = res_nopt(statp, n, buf, (int)sizeof(buf), anslen);
2621			rdata = &buf[n];
2622			if (n > 0 && (statp->options & RES_NSID) != 0U) {
2623				n = res_nopt_rdata(statp, n, buf,
2624				    (int)sizeof(buf),
2625				    rdata, NS_OPT_NSID, 0, NULL);
2626			}
2627		}
2628#endif
2629		if (n <= 0) {
2630#ifdef DEBUG
2631			if (statp->options & RES_DEBUG)
2632				printf(";; res_nquery: mkquery failed\n");
2633#endif
2634			h_errno = NO_RECOVERY;
2635			return n;
2636		}
2637		n = res_nsend(statp, buf, n, answer, anslen);
2638		if (n < 0) {
2639#ifdef RES_USE_EDNS0
2640			/* if the query choked with EDNS0, retry without EDNS0 */
2641			if ((statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U &&
2642			    ((oflags ^ statp->_flags) & RES_F_EDNS0ERR) != 0) {
2643				statp->_flags |= RES_F_EDNS0ERR;
2644				if (statp->options & RES_DEBUG)
2645					printf(";; res_nquery: retry without EDNS0\n");
2646				goto again;
2647			}
2648#endif
2649#if 0
2650#ifdef DEBUG
2651			if (statp->options & RES_DEBUG)
2652				printf(";; res_query: send error\n");
2653#endif
2654			h_errno = TRY_AGAIN;
2655			return n;
2656#endif
2657		}
2658
2659		if (n < 0 || hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
2660			rcode = hp->rcode;	/* record most recent error */
2661#ifdef DEBUG
2662			if (statp->options & RES_DEBUG)
2663				printf(";; rcode = (%s), counts = an:%d ns:%d ar:%d\n",
2664				       p_rcode(hp->rcode),
2665				       ntohs(hp->ancount),
2666				       ntohs(hp->nscount),
2667				       ntohs(hp->arcount));
2668#endif
2669			continue;
2670		}
2671
2672		ancount += ntohs(hp->ancount);
2673
2674		t->n = n;
2675	}
2676
2677	if (ancount == 0) {
2678		switch (rcode) {
2679		case NXDOMAIN:
2680			h_errno = HOST_NOT_FOUND;
2681			break;
2682		case SERVFAIL:
2683			h_errno = TRY_AGAIN;
2684			break;
2685		case NOERROR:
2686			h_errno = NO_DATA;
2687			break;
2688		case FORMERR:
2689		case NOTIMP:
2690		case REFUSED:
2691		default:
2692			h_errno = NO_RECOVERY;
2693			break;
2694		}
2695		return -1;
2696	}
2697	return ancount;
2698}
2699
2700/*
2701 * Formulate a normal query, send, and retrieve answer in supplied buffer.
2702 * Return the size of the response on success, -1 on error.
2703 * If enabled, implement search rules until answer or unrecoverable failure
2704 * is detected.	 Error code, if any, is left in h_errno.
2705 */
2706static int
2707res_searchN(const char *name, struct res_target *target, res_state res)
2708{
2709	const char *cp, * const *domain;
2710	HEADER *hp;
2711	u_int dots;
2712	char buf[MAXHOSTNAMELEN];
2713	int trailing_dot, ret, saved_herrno;
2714	int got_nodata = 0, got_servfail = 0, tried_as_is = 0;
2715
2716	_DIAGASSERT(name != NULL);
2717	_DIAGASSERT(target != NULL);
2718
2719	hp = (HEADER *)(void *)target->answer;	/*XXX*/
2720
2721	errno = 0;
2722	h_errno = HOST_NOT_FOUND;	/* default, if we never query */
2723	dots = 0;
2724	for (cp = name; *cp; cp++)
2725		dots += (*cp == '.');
2726	trailing_dot = 0;
2727	if (cp > name && *--cp == '.')
2728		trailing_dot++;
2729
2730	/*
2731	 * if there aren't any dots, it could be a user-level alias
2732	 */
2733	if (!dots && (cp = res_hostalias(res, name, buf, sizeof(buf))) != NULL) {
2734		ret = res_queryN(cp, target, res);
2735		return ret;
2736	}
2737
2738	/*
2739	 * If there are dots in the name already, let's just give it a try
2740	 * 'as is'.  The threshold can be set with the "ndots" option.
2741	 */
2742	saved_herrno = -1;
2743	if (dots >= res->ndots) {
2744		ret = res_querydomainN(name, NULL, target, res);
2745		if (ret > 0)
2746			return ret;
2747		saved_herrno = h_errno;
2748		tried_as_is++;
2749	}
2750
2751	/*
2752	 * We do at least one level of search if
2753	 *	- there is no dot and RES_DEFNAME is set, or
2754	 *	- there is at least one dot, there is no trailing dot,
2755	 *	  and RES_DNSRCH is set.
2756	 */
2757	if ((!dots && (res->options & RES_DEFNAMES)) ||
2758	    (dots && !trailing_dot && (res->options & RES_DNSRCH))) {
2759		int done = 0;
2760
2761		for (domain = (const char * const *)res->dnsrch;
2762		   *domain && !done;
2763		   domain++) {
2764
2765			ret = res_querydomainN(name, *domain, target, res);
2766			if (ret > 0)
2767				return ret;
2768
2769			/*
2770			 * If no server present, give up.
2771			 * If name isn't found in this domain,
2772			 * keep trying higher domains in the search list
2773			 * (if that's enabled).
2774			 * On a NO_DATA error, keep trying, otherwise
2775			 * a wildcard entry of another type could keep us
2776			 * from finding this entry higher in the domain.
2777			 * If we get some other error (negative answer or
2778			 * server failure), then stop searching up,
2779			 * but try the input name below in case it's
2780			 * fully-qualified.
2781			 */
2782			if (errno == ECONNREFUSED) {
2783				h_errno = TRY_AGAIN;
2784				return -1;
2785			}
2786
2787			switch (h_errno) {
2788			case NO_DATA:
2789				got_nodata++;
2790				/* FALLTHROUGH */
2791			case HOST_NOT_FOUND:
2792				/* keep trying */
2793				break;
2794			case TRY_AGAIN:
2795				if (hp->rcode == SERVFAIL) {
2796					/* try next search element, if any */
2797					got_servfail++;
2798					break;
2799				}
2800				/* FALLTHROUGH */
2801			default:
2802				/* anything else implies that we're done */
2803				done++;
2804			}
2805			/*
2806			 * if we got here for some reason other than DNSRCH,
2807			 * we only wanted one iteration of the loop, so stop.
2808			 */
2809			if (!(res->options & RES_DNSRCH))
2810				done++;
2811		}
2812	}
2813
2814	/*
2815	 * if we have not already tried the name "as is", do that now.
2816	 * note that we do this regardless of how many dots were in the
2817	 * name or whether it ends with a dot.
2818	 */
2819	if (!tried_as_is) {
2820		ret = res_querydomainN(name, NULL, target, res);
2821		if (ret > 0)
2822			return ret;
2823	}
2824
2825	/*
2826	 * if we got here, we didn't satisfy the search.
2827	 * if we did an initial full query, return that query's h_errno
2828	 * (note that we wouldn't be here if that query had succeeded).
2829	 * else if we ever got a nodata, send that back as the reason.
2830	 * else send back meaningless h_errno, that being the one from
2831	 * the last DNSRCH we did.
2832	 */
2833	if (saved_herrno != -1)
2834		h_errno = saved_herrno;
2835	else if (got_nodata)
2836		h_errno = NO_DATA;
2837	else if (got_servfail)
2838		h_errno = TRY_AGAIN;
2839	return -1;
2840}
2841
2842/*
2843 * Perform a call on res_query on the concatenation of name and domain,
2844 * removing a trailing dot from name if domain is NULL.
2845 */
2846static int
2847res_querydomainN(const char *name, const char *domain,
2848    struct res_target *target, res_state res)
2849{
2850	char nbuf[MAXDNAME];
2851	const char *longname = nbuf;
2852	size_t n, d;
2853
2854	_DIAGASSERT(name != NULL);
2855	/* XXX: target may be NULL??? */
2856
2857#ifdef DEBUG
2858	if (res->options & RES_DEBUG)
2859		printf(";; res_querydomain(%s, %s)\n",
2860			name, domain?domain:"<Nil>");
2861#endif
2862	if (domain == NULL) {
2863		/*
2864		 * Check for trailing '.';
2865		 * copy without '.' if present.
2866		 */
2867		n = strlen(name);
2868		if (n + 1 > sizeof(nbuf)) {
2869			h_errno = NO_RECOVERY;
2870			return -1;
2871		}
2872		if (n > 0 && name[--n] == '.') {
2873			strncpy(nbuf, name, n);
2874			nbuf[n] = '\0';
2875		} else
2876			longname = name;
2877	} else {
2878		n = strlen(name);
2879		d = strlen(domain);
2880		if (n + 1 + d + 1 > sizeof(nbuf)) {
2881			h_errno = NO_RECOVERY;
2882			return -1;
2883		}
2884		snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain);
2885	}
2886	return res_queryN(longname, target, res);
2887}
2888
2889#ifdef TEST
2890int
2891main(int argc, char *argv[]) {
2892	struct addrinfo *ai, *sai;
2893	int i, e;
2894	char buf[1024];
2895
2896	for (i = 1; i < argc; i++) {
2897		if ((e = getaddrinfo(argv[i], NULL, NULL, &sai)) != 0)
2898			warnx("%s: %s", argv[i], gai_strerror(e));
2899		for (ai = sai; ai; ai = ai->ai_next) {
2900			sockaddr_snprintf(buf, sizeof(buf), "%a", ai->ai_addr);
2901             		printf("flags=0x%x family=%d socktype=%d protocol=%d "
2902			    "addrlen=%zu addr=%s canonname=%s next=%p\n",
2903			    ai->ai_flags,
2904             		    ai->ai_family,
2905             		    ai->ai_socktype,
2906             		    ai->ai_protocol,
2907             		    (size_t)ai->ai_addrlen,
2908			    buf,
2909			    ai->ai_canonname,
2910			    ai->ai_next);
2911		}
2912		if (sai)
2913			freeaddrinfo(sai);
2914	}
2915	return 0;
2916}
2917#endif
2918