1/* $NetBSD: getaddrinfo.c,v 1.119 2018/12/13 04:41:41 dholland 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 2018/12/13 04:41:41 dholland Exp $");
59#endif /* LIBC_SCCS and not lint */
60
61#ifndef RUMP_ACTION
62#include "namespace.h"
63#endif
64#include <sys/types.h>
65#include <sys/param.h>
66#include <sys/socket.h>
67#include <sys/ioctl.h>
68#include <sys/sysctl.h>
69#include <net/if.h>
70#include <netinet/in.h>
71#include <netinet6/in6_var.h>
72#include <arpa/inet.h>
73#include <arpa/nameser.h>
74#include <assert.h>
75#include <ctype.h>
76#include <errno.h>
77#include <netdb.h>
78#include <resolv.h>
79#include <stddef.h>
80#include <stdio.h>
81#include <stdlib.h>
82#include <string.h>
83#include <unistd.h>
84#include <ifaddrs.h>
85
86#include <syslog.h>
87#include <stdarg.h>
88#include <nsswitch.h>
89
90#ifdef YP
91#include <rpc/rpc.h>
92#include <rpcsvc/yp_prot.h>
93#include <rpcsvc/ypclnt.h>
94#endif
95
96#include "servent.h"
97
98#ifndef RUMP_ACTION
99#ifdef __weak_alias
100__weak_alias(getaddrinfo,_getaddrinfo)
101__weak_alias(allocaddrinfo,_allocaddrinfo)
102__weak_alias(freeaddrinfo,_freeaddrinfo)
103__weak_alias(gai_strerror,_gai_strerror)
104#endif
105#endif
106
107#define SUCCESS 0
108#define ANY 0
109#define YES 1
110#define NO 0
111
112#define sa4addr(sa) ((void *)&((struct sockaddr_in *)(void *)sa)->sin_addr)
113#define sa6addr(sa) ((void *)&((struct sockaddr_in6 *)(void *)sa)->sin6_addr)
114
115static const char in_addrany[] = { 0, 0, 0, 0 };
116static const char in_loopback[] = { 127, 0, 0, 1 };
117#ifdef INET6
118static const char in6_addrany[] = {
119 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
120};
121static const char in6_loopback[] = {
122 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
123};
124#endif
125
126struct policyqueue {
127 TAILQ_ENTRY(policyqueue) pc_entry;
128#ifdef INET6
129 struct in6_addrpolicy pc_policy;
130#endif
131};
132TAILQ_HEAD(policyhead, policyqueue);
133
134static const struct afd {
135 int a_af;
136 int a_addrlen;
137 int a_socklen;
138 int a_off;
139 const char *a_addrany;
140 const char *a_loopback;
141 int a_scoped;
142} afdl [] = {
143#ifdef INET6
144 {PF_INET6, sizeof(struct in6_addr),
145 sizeof(struct sockaddr_in6),
146 offsetof(struct sockaddr_in6, sin6_addr),
147 in6_addrany, in6_loopback, 1},
148#endif
149 {PF_INET, sizeof(struct in_addr),
150 sizeof(struct sockaddr_in),
151 offsetof(struct sockaddr_in, sin_addr),
152 in_addrany, in_loopback, 0},
153 {0, 0, 0, 0, NULL, NULL, 0},
154};
155
156struct explore {
157 int e_af;
158 int e_socktype;
159 int e_protocol;
160 const char *e_protostr;
161 int e_wild;
162#define WILD_AF(ex) ((ex)->e_wild & 0x01)
163#define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02)
164#define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04)
165};
166
167static const struct explore explore[] = {
168#if 0
169 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 },
170#endif
171#ifdef INET6
172 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
173 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
174 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
175#endif
176 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
177 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
178 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
179 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
180 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
181 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 },
182 { -1, 0, 0, NULL, 0 },
183};
184
185#ifdef INET6
186#define PTON_MAX 16
187#else
188#define PTON_MAX 4
189#endif
190
191#define AIO_SRCFLAG_DEPRECATED 0x1
192
193struct ai_order {
194 union {
195 struct sockaddr_storage aiou_ss;
196 struct sockaddr aiou_sa;
197 } aio_src_un;
198#define aio_srcsa aio_src_un.aiou_sa
199 u_int32_t aio_srcflag;
200 int aio_srcscope;
201 int aio_dstscope;
202 struct policyqueue *aio_srcpolicy;
203 struct policyqueue *aio_dstpolicy;
204 struct addrinfo *aio_ai;
205 int aio_matchlen;
206};
207
208static const ns_src default_dns_files[] = {
209 { NSSRC_FILES, NS_SUCCESS },
210 { NSSRC_DNS, NS_SUCCESS },
211 { 0, 0 }
212};
213
214#define MAXPACKET (64*1024)
215
216typedef union {
217 HEADER hdr;
218 u_char buf[MAXPACKET];
219} querybuf;
220
221struct res_target {
222 struct res_target *next;
223 const char *name; /* domain name */
224 int qclass, qtype; /* class and type of query */
225 u_char *answer; /* buffer to put answer */
226 int anslen; /* size of answer buffer */
227 int n; /* result length */
228};
229
230struct srvinfo {
231 struct srvinfo *next;
232 char name[MAXDNAME];
233 int port, pri, weight;
234};
235
236static int gai_srvok(const char *);
237static int str2number(const char *);
238static int explore_fqdn(const struct addrinfo *, const char *,
239 const char *, struct addrinfo **, struct servent_data *);
240static int explore_null(const struct addrinfo *,
241 const char *, struct addrinfo **, struct servent_data *);
242static int explore_numeric(const struct addrinfo *, const char *,
243 const char *, struct addrinfo **, const char *, struct servent_data *);
244static int explore_numeric_scope(const struct addrinfo *, const char *,
245 const char *, struct addrinfo **, struct servent_data *);
246static int get_canonname(const struct addrinfo *,
247 struct addrinfo *, const char *);
248static struct addrinfo *get_ai(const struct addrinfo *,
249 const struct afd *, const char *);
250static int get_portmatch(const struct addrinfo *, const char *,
251 struct servent_data *);
252static int get_port(const struct addrinfo *, const char *, int,
253 struct servent_data *);
254static const struct afd *find_afd(int);
255static int addrconfig(uint64_t *);
256static void set_source(struct ai_order *, struct policyhead *,
257 struct servent_data *);
258static int comp_dst(const void *, const void *);
259#ifdef INET6
260static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *);
261#endif
262static int gai_addr2scopetype(struct sockaddr *);
263
264static int reorder(struct addrinfo *, struct servent_data *);
265static int get_addrselectpolicy(struct policyhead *);
266static void free_addrselectpolicy(struct policyhead *);
267static struct policyqueue *match_addrselectpolicy(struct sockaddr *,
268 struct policyhead *);
269static int matchlen(struct sockaddr *, struct sockaddr *);
270
271static struct addrinfo *getanswer(res_state, const querybuf *, int,
272 const char *, int, const struct addrinfo *);
273static void aisort(struct addrinfo *s, res_state res);
274static struct addrinfo * _dns_query(struct res_target *,
275 const struct addrinfo *, res_state, int);
276static struct addrinfo * _dns_srv_lookup(const char *, const char *,
277 const struct addrinfo *);
278static struct addrinfo * _dns_host_lookup(const char *,
279 const struct addrinfo *);
280static int _dns_getaddrinfo(void *, void *, va_list);
281static void _sethtent(FILE **);
282static void _endhtent(FILE **);
283static struct addrinfo *_gethtent(FILE **, const char *,
284 const struct addrinfo *);
285static int _files_getaddrinfo(void *, void *, va_list);
286#ifdef YP
287static struct addrinfo *_yphostent(char *, const struct addrinfo *);
288static int _yp_getaddrinfo(void *, void *, va_list);
289#endif
290
291static int res_queryN(const char *, struct res_target *, res_state);
292static int res_searchN(const char *, struct res_target *, res_state);
293static int res_querydomainN(const char *, const char *,
294 struct res_target *, res_state);
295
296static const char * const ai_errlist[] = {
297 "Success",
298 "Address family for hostname not supported", /* EAI_ADDRFAMILY */
299 "Temporary failure in name resolution", /* EAI_AGAIN */
300 "Invalid value for ai_flags", /* EAI_BADFLAGS */
301 "Non-recoverable failure in name resolution", /* EAI_FAIL */
302 "ai_family not supported", /* EAI_FAMILY */
303 "Memory allocation failure", /* EAI_MEMORY */
304 "No address associated with hostname", /* EAI_NODATA */
305 "hostname or servname not provided or not known", /* EAI_NONAME */
306 "servname not supported for ai_socktype", /* EAI_SERVICE */
307 "ai_socktype not supported", /* EAI_SOCKTYPE */
308 "System error returned in errno", /* EAI_SYSTEM */
309 "Invalid value for hints", /* EAI_BADHINTS */
310 "Resolved protocol is unknown", /* EAI_PROTOCOL */
311 "Argument buffer overflow", /* EAI_OVERFLOW */
312 "Unknown error", /* EAI_MAX */
313};
314
315/* XXX macros that make external reference is BAD. */
316
317#define GET_AI(ai, afd, addr) \
318do { \
319 /* external reference: pai, error, and label free */ \
320 (ai) = get_ai(pai, (afd), (addr)); \
321 if ((ai) == NULL) { \
322 error = EAI_MEMORY; \
323 goto free; \
324 } \
325} while (/*CONSTCOND*/0)
326
327#define GET_PORT(ai, serv, svd) \
328do { \
329 /* external reference: error and label free */ \
330 error = get_port((ai), (serv), 0, (svd)); \
331 if (error != 0) \
332 goto free; \
333} while (/*CONSTCOND*/0)
334
335#define GET_CANONNAME(ai, str) \
336do { \
337 /* external reference: pai, error and label free */ \
338 error = get_canonname(pai, (ai), (str)); \
339 if (error != 0) \
340 goto free; \
341} while (/*CONSTCOND*/0)
342
343#define ERR(err) \
344do { \
345 /* external reference: error, and label bad */ \
346 error = (err); \
347 goto bad; \
348 /*NOTREACHED*/ \
349} while (/*CONSTCOND*/0)
350
351#define MATCH_FAMILY(x, y, w) \
352 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || \
353 (y) == PF_UNSPEC)))
354#define MATCH(x, y, w) \
355 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
356
357const char *
358gai_strerror(int ecode)
359{
360 if (ecode < 0 || ecode > EAI_MAX)
361 ecode = EAI_MAX;
362 return ai_errlist[ecode];
363}
364
365void
366freeaddrinfo(struct addrinfo *ai)
367{
368 struct addrinfo *next;
369
370 _DIAGASSERT(ai != NULL);
371
372 do {
373 next = ai->ai_next;
374 if (ai->ai_canonname)
375 free(ai->ai_canonname);
376 /* no need to free(ai->ai_addr) */
377 free(ai);
378 ai = next;
379 } while (ai);
380}
381
382/*
383 * We don't want localization to affect us
384 */
385#define PERIOD '.'
386#define hyphenchar(c) ((c) == '-')
387#define periodchar(c) ((c) == PERIOD)
388#define underschar(c) ((c) == '_')
389#define alphachar(c) (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z'))
390#define digitchar(c) ((c) >= '0' && (c) <= '9')
391
392#define firstchar(c) (alphachar(c) || digitchar(c) || underschar(c))
393#define lastchar(c) (alphachar(c) || digitchar(c))
394#define middlechar(c) (lastchar(c) || hyphenchar(c))
395
396static int
397gai_srvok(const char *dn)
398{
399 int nch, pch, ch;
400
401 for (pch = PERIOD, nch = ch = *dn++; ch != '\0'; pch = ch, ch = nch) {
402 if (periodchar(ch))
403 continue;
404 if (periodchar(pch)) {
405 if (!firstchar(ch))
406 return 0;
407 } else if (periodchar(nch) || nch == '\0') {
408 if (!lastchar(ch))
409 return 0;
410 } else if (!middlechar(ch))
411 return 0;
412 }
413 return 1;
414}
415
416static in_port_t *
417getport(struct addrinfo *ai) {
418 static in_port_t p;
419
420 switch (ai->ai_family) {
421 case AF_INET:
422 return &((struct sockaddr_in *)(void *)ai->ai_addr)->sin_port;
423#ifdef INET6
424 case AF_INET6:
425 return &((struct sockaddr_in6 *)(void *)ai->ai_addr)->sin6_port;
426#endif
427 default:
428 p = 0;
429 /* XXX: abort()? */
430 return &p;
431 }
432}
433
434static int
435str2number(const char *p)
436{
437 char *ep;
438 unsigned long v;
439
440 _DIAGASSERT(p != NULL);
441
442 if (*p == '\0')
443 return -1;
444 ep = NULL;
445 errno = 0;
446 v = strtoul(p, &ep, 10);
447 if (errno == 0 && ep && *ep == '\0' && v <= INT_MAX)
448 return (int)v;
449 else
450 return -1;
451}
452
453int
454getaddrinfo(const char *hostname, const char *servname,
455 const struct addrinfo *hints, struct addrinfo **res)
456{
457 struct addrinfo sentinel;
458 struct addrinfo *cur;
459 int error = 0;
460 struct addrinfo ai;
461 struct addrinfo ai0;
462 struct addrinfo *pai;
463 const struct explore *ex;
464 struct servent_data svd;
465 uint64_t mask = (uint64_t)~0ULL;
466 int numeric = 0;
467
468 /* hostname is allowed to be NULL */
469 /* servname is allowed to be NULL */
470 /* hints is allowed to be NULL */
471 _DIAGASSERT(res != NULL);
472
473 (void)memset(&svd, 0, sizeof(svd));
474 memset(&sentinel, 0, sizeof(sentinel));
475 cur = &sentinel;
476 memset(&ai, 0, sizeof(ai));
477 pai = &ai;
478 pai->ai_flags = 0;
479 pai->ai_family = PF_UNSPEC;
480 pai->ai_socktype = ANY;
481 pai->ai_protocol = ANY;
482 pai->ai_addrlen = 0;
483 pai->ai_canonname = NULL;
484 pai->ai_addr = NULL;
485 pai->ai_next = NULL;
486
487 if (hostname == NULL && servname == NULL)
488 return EAI_NONAME;
489 if (hints) {
490 /* error check for hints */
491 if (hints->ai_addrlen || hints->ai_canonname ||
492 hints->ai_addr || hints->ai_next)
493 ERR(EAI_BADHINTS); /* xxx */
494 if (hints->ai_flags & ~AI_MASK)
495 ERR(EAI_BADFLAGS);
496 switch (hints->ai_family) {
497 case PF_UNSPEC:
498 case PF_INET:
499#ifdef INET6
500 case PF_INET6:
501#endif
502 break;
503 default:
504 ERR(EAI_FAMILY);
505 }
506 memcpy(pai, hints, sizeof(*pai));
507
508 /*
509 * if both socktype/protocol are specified, check if they
510 * are meaningful combination.
511 */
512 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
513 for (ex = explore; ex->e_af >= 0; ex++) {
514 if (pai->ai_family != ex->e_af)
515 continue;
516 if (ex->e_socktype == ANY)
517 continue;
518 if (ex->e_protocol == ANY)
519 continue;
520 if (pai->ai_socktype == ex->e_socktype
521 && pai->ai_protocol != ex->e_protocol) {
522 ERR(EAI_BADHINTS);
523 }
524 }
525 }
526 }
527
528 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && addrconfig(&mask) == -1)
529 ERR(EAI_FAIL);
530
531 /*
532 * check for special cases. (1) numeric servname is disallowed if
533 * socktype/protocol are left unspecified. (2) servname is disallowed
534 * for raw and other inet{,6} sockets.
535 */
536 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
537#ifdef PF_INET6
538 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
539#endif
540 ) {
541 ai0 = *pai; /* backup *pai */
542
543 if (pai->ai_family == PF_UNSPEC) {
544#ifdef PF_INET6
545 pai->ai_family = PF_INET6;
546#else
547 pai->ai_family = PF_INET;
548#endif
549 }
550 error = get_portmatch(pai, servname, &svd);
551 if (error)
552 goto bad;
553
554 *pai = ai0;
555 }
556
557 ai0 = *pai;
558
559 /* NULL hostname, or numeric hostname */
560 for (ex = explore; ex->e_af >= 0; ex++) {
561 *pai = ai0;
562
563 /* ADDRCONFIG check */
564 if ((((uint64_t)1 << ex->e_af) & mask) == 0)
565 continue;
566
567 /* PF_UNSPEC entries are prepared for DNS queries only */
568 if (ex->e_af == PF_UNSPEC)
569 continue;
570
571 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
572 continue;
573 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex)))
574 continue;
575 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex)))
576 continue;
577 if (pai->ai_family == PF_UNSPEC)
578 pai->ai_family = ex->e_af;
579 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
580 pai->ai_socktype = ex->e_socktype;
581 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
582 pai->ai_protocol = ex->e_protocol;
583
584 if (hostname == NULL)
585 error = explore_null(pai, servname, &cur->ai_next,
586 &svd);
587 else
588 error = explore_numeric_scope(pai, hostname, servname,
589 &cur->ai_next, &svd);
590
591 if (error)
592 goto free;
593
594 while (cur->ai_next)
595 cur = cur->ai_next;
596 }
597
598 /*
599 * XXX
600 * If numeric representation of AF1 can be interpreted as FQDN
601 * representation of AF2, we need to think again about the code below.
602 */
603 if (sentinel.ai_next) {
604 numeric = 1;
605 goto good;
606 }
607
608 if (hostname == NULL)
609 ERR(EAI_NODATA);
610 if (pai->ai_flags & AI_NUMERICHOST)
611 ERR(EAI_NONAME);
612
613 /*
614 * hostname as alphabetical name.
615 * we would like to prefer AF_INET6 than AF_INET, so we'll make a
616 * outer loop by AFs.
617 */
618 for (ex = explore; ex->e_af >= 0; ex++) {
619 *pai = ai0;
620
621
622 /* ADDRCONFIG check */
623 /* PF_UNSPEC entries are prepared for DNS queries only */
624 if (ex->e_af != PF_UNSPEC &&
625 (((uint64_t)1 << ex->e_af) & mask) == 0)
626 continue;
627
628 /* require exact match for family field */
629 if (pai->ai_family != ex->e_af)
630 continue;
631
632 if (!MATCH(pai->ai_socktype, ex->e_socktype,
633 WILD_SOCKTYPE(ex))) {
634 continue;
635 }
636 if (!MATCH(pai->ai_protocol, ex->e_protocol,
637 WILD_PROTOCOL(ex))) {
638 continue;
639 }
640
641 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
642 pai->ai_socktype = ex->e_socktype;
643 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
644 pai->ai_protocol = ex->e_protocol;
645
646 error = explore_fqdn(pai, hostname, servname, &cur->ai_next,
647 &svd);
648
649 while (cur && cur->ai_next)
650 cur = cur->ai_next;
651 }
652
653 /* XXX */
654 if (sentinel.ai_next)
655 error = 0;
656
657 if (error)
658 goto free;
659
660 if (sentinel.ai_next) {
661 good:
662 /*
663 * If the returned entry is for an active connection,
664 * and the given name is not numeric, reorder the
665 * list, so that the application would try the list
666 * in the most efficient order. Since the head entry
667 * of the original list may contain ai_canonname and
668 * that entry may be moved elsewhere in the new list,
669 * we keep the pointer and will restore it in the new
670 * head entry. (Note that RFC3493 requires the head
671 * entry store it when requested by the caller).
672 */
673 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) {
674 if (!numeric) {
675 char *canonname;
676
677 canonname = sentinel.ai_next->ai_canonname;
678 sentinel.ai_next->ai_canonname = NULL;
679 (void)reorder(&sentinel, &svd);
680 if (sentinel.ai_next->ai_canonname == NULL) {
681 sentinel.ai_next->ai_canonname
682 = canonname;
683 } else if (canonname != NULL)
684 free(canonname);
685 }
686 }
687 endservent_r(&svd);
688 *res = sentinel.ai_next;
689 return SUCCESS;
690 } else
691 error = EAI_FAIL;
692 free:
693 bad:
694 endservent_r(&svd);
695 if (sentinel.ai_next)
696 freeaddrinfo(sentinel.ai_next);
697 *res = NULL;
698 return error;
699}
700
701static int
702reorder(struct addrinfo *sentinel, struct servent_data *svd)
703{
704 struct addrinfo *ai, **aip;
705 struct ai_order *aio;
706 int i, n;
707 struct policyhead policyhead;
708
709 /* count the number of addrinfo elements for sorting. */
710 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++)
711 ;
712
713 /*
714 * If the number is small enough, we can skip the reordering process.
715 */
716 if (n <= 1)
717 return n;
718
719 /* allocate a temporary array for sort and initialization of it. */
720 if ((aio = malloc(sizeof(*aio) * n)) == NULL)
721 return n; /* give up reordering */
722 memset(aio, 0, sizeof(*aio) * n);
723
724 /* retrieve address selection policy from the kernel */
725 TAILQ_INIT(&policyhead);
726 if (!get_addrselectpolicy(&policyhead)) {
727 /* no policy is installed into kernel, we don't sort. */
728 free(aio);
729 return n;
730 }
731
732 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) {
733 aio[i].aio_ai = ai;
734 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr);
735 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr,
736 &policyhead);
737 set_source(&aio[i], &policyhead, svd);
738 }
739
740 /* perform sorting. */
741 qsort(aio, n, sizeof(*aio), comp_dst);
742
743 /* reorder the addrinfo chain. */
744 for (i = 0, aip = &sentinel->ai_next; i < n; i++) {
745 *aip = aio[i].aio_ai;
746 aip = &aio[i].aio_ai->ai_next;
747 }
748 *aip = NULL;
749
750 /* cleanup and return */
751 free(aio);
752 free_addrselectpolicy(&policyhead);
753 return n;
754}
755
756static int
757get_addrselectpolicy(struct policyhead *head)
758{
759#ifdef INET6
760 static const int mib[] = {
761 CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY };
762 static const u_int miblen = (u_int)__arraycount(mib);
763 size_t l;
764 char *buf;
765 struct in6_addrpolicy *pol, *ep;
766
767 if (sysctl(mib, miblen, NULL, &l, NULL, 0) < 0)
768 return 0;
769 if (l == 0)
770 return 0;
771 if ((buf = malloc(l)) == NULL)
772 return 0;
773 if (sysctl(mib, miblen, buf, &l, NULL, 0) < 0) {
774 free(buf);
775 return 0;
776 }
777
778 ep = (void *)(buf + l);
779 for (pol = (void *)buf; pol + 1 <= ep; pol++) {
780 struct policyqueue *new;
781
782 if ((new = malloc(sizeof(*new))) == NULL) {
783 free_addrselectpolicy(head); /* make the list empty */
784 break;
785 }
786 new->pc_policy = *pol;
787 TAILQ_INSERT_TAIL(head, new, pc_entry);
788 }
789
790 free(buf);
791 return 1;
792#else
793 return 0;
794#endif
795}
796
797static void
798free_addrselectpolicy(struct policyhead *head)
799{
800 struct policyqueue *ent, *nent;
801
802 for (ent = TAILQ_FIRST(head); ent; ent = nent) {
803 nent = TAILQ_NEXT(ent, pc_entry);
804 TAILQ_REMOVE(head, ent, pc_entry);
805 free(ent);
806 }
807}
808
809static struct policyqueue *
810match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head)
811{
812#ifdef INET6
813 struct policyqueue *ent, *bestent = NULL;
814 struct in6_addrpolicy *pol;
815 int curmatchlen, bestmatchlen = -1;
816 u_char *mp, *ep, *k, *p;
817 u_int m;
818 struct sockaddr_in6 key;
819
820 switch(addr->sa_family) {
821 case AF_INET6:
822 memcpy(&key, addr, sizeof(key));
823 break;
824 case AF_INET:
825 /* convert the address into IPv4-mapped IPv6 address. */
826 memset(&key, 0, sizeof(key));
827 key.sin6_family = AF_INET6;
828 key.sin6_len = sizeof(key);
829 key.sin6_addr.s6_addr[10] = 0xff;
830 key.sin6_addr.s6_addr[11] = 0xff;
831 memcpy(&key.sin6_addr.s6_addr[12], sa4addr(addr), 4);
832 break;
833 default:
834 return NULL;
835 }
836
837 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) {
838 pol = &ent->pc_policy;
839 curmatchlen = 0;
840
841 mp = (void *)&pol->addrmask.sin6_addr;
842 ep = mp + 16; /* XXX: scope field? */
843 k = (void *)&key.sin6_addr;
844 p = (void *)&pol->addr.sin6_addr;
845 for (; mp < ep && *mp; mp++, k++, p++) {
846 m = *mp;
847 if ((*k & m) != *p)
848 goto next; /* not match */
849 if (m == 0xff) /* short cut for a typical case */
850 curmatchlen += 8;
851 else {
852 while (m >= 0x80) {
853 curmatchlen++;
854 m <<= 1;
855 }
856 }
857 }
858
859 /* matched. check if this is better than the current best. */
860 if (curmatchlen > bestmatchlen) {
861 bestent = ent;
862 bestmatchlen = curmatchlen;
863 }
864
865 next:
866 continue;
867 }
868
869 return bestent;
870#else
871 return NULL;
872#endif
873
874}
875
876static void
877set_source(struct ai_order *aio, struct policyhead *ph,
878 struct servent_data *svd)
879{
880 struct addrinfo ai = *aio->aio_ai;
881 struct sockaddr_storage ss;
882 socklen_t srclen;
883 int s;
884
885 /* set unspec ("no source is available"), just in case */
886 aio->aio_srcsa.sa_family = AF_UNSPEC;
887 aio->aio_srcscope = -1;
888
889 switch(ai.ai_family) {
890 case AF_INET:
891#ifdef INET6
892 case AF_INET6:
893#endif
894 break;
895 default: /* ignore unsupported AFs explicitly */
896 return;
897 }
898
899 /* XXX: make a dummy addrinfo to call connect() */
900 ai.ai_socktype = SOCK_DGRAM;
901 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */
902 ai.ai_next = NULL;
903 memset(&ss, 0, sizeof(ss));
904 memcpy(&ss, ai.ai_addr, ai.ai_addrlen);
905 ai.ai_addr = (void *)&ss;
906 get_port(&ai, "1", 0, svd);
907
908 /* open a socket to get the source address for the given dst */
909 if ((s = socket(ai.ai_family, ai.ai_socktype | SOCK_CLOEXEC,
910 ai.ai_protocol)) < 0)
911 return; /* give up */
912 if (connect(s, ai.ai_addr, ai.ai_addrlen) < 0)
913 goto cleanup;
914 srclen = ai.ai_addrlen;
915 if (getsockname(s, &aio->aio_srcsa, &srclen) < 0) {
916 aio->aio_srcsa.sa_family = AF_UNSPEC;
917 goto cleanup;
918 }
919 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa);
920 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph);
921 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr);
922#ifdef INET6
923 if (ai.ai_family == AF_INET6) {
924 struct in6_ifreq ifr6;
925 u_int32_t flags6;
926
927 memset(&ifr6, 0, sizeof(ifr6));
928 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen);
929 if (ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) {
930 flags6 = ifr6.ifr_ifru.ifru_flags6;
931 if ((flags6 & IN6_IFF_DEPRECATED))
932 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED;
933 }
934 }
935#endif
936
937 cleanup:
938 close(s);
939 return;
940}
941
942static int
943matchlen(struct sockaddr *src, struct sockaddr *dst)
944{
945 int match = 0;
946 u_char *s, *d;
947 u_char *lim;
948 u_int r, addrlen;
949
950 switch (src->sa_family) {
951#ifdef INET6
952 case AF_INET6:
953 s = sa6addr(src);
954 d = sa6addr(dst);
955 addrlen = sizeof(struct in6_addr);
956 lim = s + addrlen;
957 break;
958#endif
959 case AF_INET:
960 s = sa4addr(src);
961 d = sa4addr(dst);
962 addrlen = sizeof(struct in_addr);
963 lim = s + addrlen;
964 break;
965 default:
966 return 0;
967 }
968
969 while (s < lim)
970 if ((r = (*d++ ^ *s++)) != 0) {
971 while (r < addrlen * 8) {
972 match++;
973 r <<= 1;
974 }
975 break;
976 } else
977 match += 8;
978 return match;
979}
980
981static int
982comp_dst(const void *arg1, const void *arg2)
983{
984 const struct ai_order *dst1 = arg1, *dst2 = arg2;
985
986 /*
987 * Rule 1: Avoid unusable destinations.
988 * XXX: we currently do not consider if an appropriate route exists.
989 */
990 if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
991 dst2->aio_srcsa.sa_family == AF_UNSPEC) {
992 return -1;
993 }
994 if (dst1->aio_srcsa.sa_family == AF_UNSPEC &&
995 dst2->aio_srcsa.sa_family != AF_UNSPEC) {
996 return 1;
997 }
998
999 /* Rule 2: Prefer matching scope. */
1000 if (dst1->aio_dstscope == dst1->aio_srcscope &&
1001 dst2->aio_dstscope != dst2->aio_srcscope) {
1002 return -1;
1003 }
1004 if (dst1->aio_dstscope != dst1->aio_srcscope &&
1005 dst2->aio_dstscope == dst2->aio_srcscope) {
1006 return 1;
1007 }
1008
1009 /* Rule 3: Avoid deprecated addresses. */
1010 if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
1011 dst2->aio_srcsa.sa_family != AF_UNSPEC) {
1012 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
1013 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
1014 return -1;
1015 }
1016 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
1017 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
1018 return 1;
1019 }
1020 }
1021
1022 /* Rule 4: Prefer home addresses. */
1023 /* XXX: not implemented yet */
1024
1025 /* Rule 5: Prefer matching label. */
1026#ifdef INET6
1027 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy &&
1028 dst1->aio_srcpolicy->pc_policy.label ==
1029 dst1->aio_dstpolicy->pc_policy.label &&
1030 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL ||
1031 dst2->aio_srcpolicy->pc_policy.label !=
1032 dst2->aio_dstpolicy->pc_policy.label)) {
1033 return -1;
1034 }
1035 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy &&
1036 dst2->aio_srcpolicy->pc_policy.label ==
1037 dst2->aio_dstpolicy->pc_policy.label &&
1038 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL ||
1039 dst1->aio_srcpolicy->pc_policy.label !=
1040 dst1->aio_dstpolicy->pc_policy.label)) {
1041 return 1;
1042 }
1043#endif
1044
1045 /* Rule 6: Prefer higher precedence. */
1046#ifdef INET6
1047 if (dst1->aio_dstpolicy &&
1048 (dst2->aio_dstpolicy == NULL ||
1049 dst1->aio_dstpolicy->pc_policy.preced >
1050 dst2->aio_dstpolicy->pc_policy.preced)) {
1051 return -1;
1052 }
1053 if (dst2->aio_dstpolicy &&
1054 (dst1->aio_dstpolicy == NULL ||
1055 dst2->aio_dstpolicy->pc_policy.preced >
1056 dst1->aio_dstpolicy->pc_policy.preced)) {
1057 return 1;
1058 }
1059#endif
1060
1061 /* Rule 7: Prefer native transport. */
1062 /* XXX: not implemented yet */
1063
1064 /* Rule 8: Prefer smaller scope. */
1065 if (dst1->aio_dstscope >= 0 &&
1066 dst1->aio_dstscope < dst2->aio_dstscope) {
1067 return -1;
1068 }
1069 if (dst2->aio_dstscope >= 0 &&
1070 dst2->aio_dstscope < dst1->aio_dstscope) {
1071 return 1;
1072 }
1073
1074 /*
1075 * Rule 9: Use longest matching prefix.
1076 * We compare the match length in a same AF only.
1077 */
1078 if (dst1->aio_ai->ai_addr->sa_family ==
1079 dst2->aio_ai->ai_addr->sa_family &&
1080 dst1->aio_ai->ai_addr->sa_family != AF_INET) {
1081 if (dst1->aio_matchlen > dst2->aio_matchlen) {
1082 return -1;
1083 }
1084 if (dst1->aio_matchlen < dst2->aio_matchlen) {
1085 return 1;
1086 }
1087 }
1088
1089 /* Rule 10: Otherwise, leave the order unchanged. */
1090 return -1;
1091}
1092
1093/*
1094 * Copy from scope.c.
1095 * XXX: we should standardize the functions and link them as standard
1096 * library.
1097 */
1098static int
1099gai_addr2scopetype(struct sockaddr *sa)
1100{
1101#ifdef INET6
1102 struct sockaddr_in6 *sa6;
1103#endif
1104 struct sockaddr_in *sa4;
1105 u_char *p;
1106
1107 switch(sa->sa_family) {
1108#ifdef INET6
1109 case AF_INET6:
1110 sa6 = (void *)sa;
1111 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
1112 /* just use the scope field of the multicast address */
1113 return sa6->sin6_addr.s6_addr[2] & 0x0f;
1114 }
1115 /*
1116 * Unicast addresses: map scope type to corresponding scope
1117 * value defined for multcast addresses.
1118 * XXX: hardcoded scope type values are bad...
1119 */
1120 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr))
1121 return 1; /* node local scope */
1122 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr))
1123 return 2; /* link-local scope */
1124 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr))
1125 return 5; /* site-local scope */
1126 return 14; /* global scope */
1127#endif
1128 case AF_INET:
1129 /*
1130 * IPv4 pseudo scoping according to RFC 3484.
1131 */
1132 sa4 = (void *)sa;
1133 p = (u_char *)(void *)&sa4->sin_addr;
1134 /* IPv4 autoconfiguration addresses have link-local scope. */
1135 if (p[0] == 169 && p[1] == 254)
1136 return 2;
1137 /* Private addresses have site-local scope. */
1138 if (p[0] == 10 ||
1139 (p[0] == 172 && (p[1] & 0xf0) == 16) ||
1140 (p[0] == 192 && p[1] == 168))
1141 return 14; /* XXX: It should be 5 unless NAT */
1142 /* Loopback addresses have link-local scope. */
1143 if (p[0] == 127)
1144 return 2;
1145 return 14;
1146 default:
1147 errno = EAFNOSUPPORT; /* is this a good error? */
1148 return -1;
1149 }
1150}
1151
1152/*
1153 * FQDN hostname, DNS lookup
1154 */
1155static int
1156explore_fqdn(const struct addrinfo *pai, const char *hostname,
1157 const char *servname, struct addrinfo **res, struct servent_data *svd)
1158{
1159 struct addrinfo *result;
1160 struct addrinfo *cur;
1161 int error = 0;
1162 static const ns_dtab dtab[] = {
1163 NS_FILES_CB(_files_getaddrinfo, NULL)
1164 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */
1165 NS_NIS_CB(_yp_getaddrinfo, NULL)
1166 NS_NULL_CB
1167 };
1168
1169 _DIAGASSERT(pai != NULL);
1170 /* hostname may be NULL */
1171 /* servname may be NULL */
1172 _DIAGASSERT(res != NULL);
1173
1174 result = NULL;
1175
1176 /*
1177 * if the servname does not match socktype/protocol, ignore it.
1178 */
1179 if (get_portmatch(pai, servname, svd) != 0)
1180 return 0;
1181
1182 switch (nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo",
1183 default_dns_files, hostname, pai, servname)) {
1184 case NS_TRYAGAIN:
1185 error = EAI_AGAIN;
1186 goto free;
1187 case NS_UNAVAIL:
1188 error = EAI_FAIL;
1189 goto free;
1190 case NS_NOTFOUND:
1191 error = EAI_NODATA;
1192 goto free;
1193 case NS_SUCCESS:
1194 error = 0;
1195 for (cur = result; cur; cur = cur->ai_next) {
1196 /* Check for already filled port. */
1197 if (*getport(cur))
1198 continue;
1199 GET_PORT(cur, servname, svd);
1200 /* canonname should be filled already */
1201 }
1202 break;
1203 }
1204
1205 *res = result;
1206
1207 return 0;
1208
1209free:
1210 if (result)
1211 freeaddrinfo(result);
1212 return error;
1213}
1214
1215/*
1216 * hostname == NULL.
1217 * passive socket -> anyaddr (0.0.0.0 or ::)
1218 * non-passive socket -> localhost (127.0.0.1 or ::1)
1219 */
1220static int
1221explore_null(const struct addrinfo *pai, const char *servname,
1222 struct addrinfo **res, struct servent_data *svd)
1223{
1224 int s;
1225 const struct afd *afd;
1226 struct addrinfo *cur;
1227 struct addrinfo sentinel;
1228 int error;
1229
1230 _DIAGASSERT(pai != NULL);
1231 /* servname may be NULL */
1232 _DIAGASSERT(res != NULL);
1233
1234 *res = NULL;
1235 sentinel.ai_next = NULL;
1236 cur = &sentinel;
1237
1238 /*
1239 * filter out AFs that are not supported by the kernel
1240 * XXX errno?
1241 */
1242 s = socket(pai->ai_family, SOCK_DGRAM, 0);
1243 if (s < 0) {
1244 if (errno != EMFILE)
1245 return 0;
1246 } else
1247 close(s);
1248
1249 /*
1250 * if the servname does not match socktype/protocol, ignore it.
1251 */
1252 if (get_portmatch(pai, servname, svd) != 0)
1253 return 0;
1254
1255 afd = find_afd(pai->ai_family);
1256 if (afd == NULL)
1257 return 0;
1258
1259 if (pai->ai_flags & AI_PASSIVE) {
1260 GET_AI(cur->ai_next, afd, afd->a_addrany);
1261 /* xxx meaningless?
1262 * GET_CANONNAME(cur->ai_next, "anyaddr");
1263 */
1264 GET_PORT(cur->ai_next, servname, svd);
1265 } else {
1266 GET_AI(cur->ai_next, afd, afd->a_loopback);
1267 /* xxx meaningless?
1268 * GET_CANONNAME(cur->ai_next, "localhost");
1269 */
1270 GET_PORT(cur->ai_next, servname, svd);
1271 }
1272 cur = cur->ai_next;
1273
1274 *res = sentinel.ai_next;
1275 return 0;
1276
1277free:
1278 if (sentinel.ai_next)
1279 freeaddrinfo(sentinel.ai_next);
1280 return error;
1281}
1282
1283/*
1284 * numeric hostname
1285 */
1286static int
1287explore_numeric(const struct addrinfo *pai, const char *hostname,
1288 const char *servname, struct addrinfo **res, const char *canonname,
1289 struct servent_data *svd)
1290{
1291 const struct afd *afd;
1292 struct addrinfo *cur;
1293 struct addrinfo sentinel;
1294 int error;
1295 char pton[PTON_MAX];
1296
1297 _DIAGASSERT(pai != NULL);
1298 /* hostname may be NULL */
1299 /* servname may be NULL */
1300 _DIAGASSERT(res != NULL);
1301
1302 *res = NULL;
1303 sentinel.ai_next = NULL;
1304 cur = &sentinel;
1305
1306 /*
1307 * if the servname does not match socktype/protocol, ignore it.
1308 */
1309 if (get_portmatch(pai, servname, svd) != 0)
1310 return 0;
1311
1312 afd = find_afd(pai->ai_family);
1313 if (afd == NULL)
1314 return 0;
1315
1316 switch (afd->a_af) {
1317 case AF_INET:
1318 /*
1319 * RFC3493 section 6.1, requires getaddrinfo() to accept
1320 * AF_INET formats that are accepted by inet_addr(); here
1321 * we use the equivalent inet_aton() function so we can
1322 * check for errors. inet_pton() only accepts addresses
1323 * in the dotted quad format and only in base 10, so we
1324 * need to treat AF_INET specially.
1325 *
1326 * We also check for trailing characters and fail if there
1327 * are any. This matches the inet_pton6(), but not the
1328 * inet_pton4() behavior. We choose to make the protocol
1329 * behavior consistent.
1330 */
1331 if (inet_aton(hostname, (void *)pton) == 1 &&
1332 hostname[strspn(hostname, "0123456789.xabcdefXABCDEF")]
1333 == '\0') {
1334 if (pai->ai_family == afd->a_af ||
1335 pai->ai_family == PF_UNSPEC /*?*/) {
1336 GET_AI(cur->ai_next, afd, pton);
1337 GET_PORT(cur->ai_next, servname, svd);
1338 if ((pai->ai_flags & AI_CANONNAME)) {
1339 /*
1340 * Set the numeric address itself as
1341 * the canonical name, based on a
1342 * clarification in rfc2553bis-03.
1343 */
1344 GET_CANONNAME(cur->ai_next, canonname);
1345 }
1346 while (cur && cur->ai_next)
1347 cur = cur->ai_next;
1348 } else
1349 ERR(EAI_FAMILY); /*xxx*/
1350 }
1351 break;
1352 default:
1353 if (inet_pton(afd->a_af, hostname, pton) == 1) {
1354 if (pai->ai_family == afd->a_af ||
1355 pai->ai_family == PF_UNSPEC /*?*/) {
1356 GET_AI(cur->ai_next, afd, pton);
1357 GET_PORT(cur->ai_next, servname, svd);
1358 if ((pai->ai_flags & AI_CANONNAME)) {
1359 /*
1360 * Set the numeric address itself as
1361 * the canonical name, based on a
1362 * clarification in rfc2553bis-03.
1363 */
1364 GET_CANONNAME(cur->ai_next, canonname);
1365 }
1366 while (cur->ai_next)
1367 cur = cur->ai_next;
1368 } else
1369 ERR(EAI_FAMILY); /*xxx*/
1370 }
1371 break;
1372 }
1373
1374 *res = sentinel.ai_next;
1375 return 0;
1376
1377free:
1378bad:
1379 if (sentinel.ai_next)
1380 freeaddrinfo(sentinel.ai_next);
1381 return error;
1382}
1383
1384/*
1385 * numeric hostname with scope
1386 */
1387static int
1388explore_numeric_scope(const struct addrinfo *pai, const char *hostname,
1389 const char *servname, struct addrinfo **res, struct servent_data *svd)
1390{
1391#if !defined(SCOPE_DELIMITER) || !defined(INET6)
1392 return explore_numeric(pai, hostname, servname, res, hostname, svd);
1393#else
1394 const struct afd *afd;
1395 struct addrinfo *cur;
1396 int error;
1397 char *cp, *hostname2 = NULL, *scope, *addr;
1398 struct sockaddr_in6 *sin6;
1399
1400 _DIAGASSERT(pai != NULL);
1401 /* hostname may be NULL */
1402 /* servname may be NULL */
1403 _DIAGASSERT(res != NULL);
1404
1405 /*
1406 * if the servname does not match socktype/protocol, ignore it.
1407 */
1408 if (get_portmatch(pai, servname, svd) != 0)
1409 return 0;
1410
1411 afd = find_afd(pai->ai_family);
1412 if (afd == NULL)
1413 return 0;
1414
1415 if (!afd->a_scoped)
1416 return explore_numeric(pai, hostname, servname, res, hostname,
1417 svd);
1418
1419 cp = strchr(hostname, SCOPE_DELIMITER);
1420 if (cp == NULL)
1421 return explore_numeric(pai, hostname, servname, res, hostname,
1422 svd);
1423
1424 /*
1425 * Handle special case of <scoped_address><delimiter><scope id>
1426 */
1427 hostname2 = strdup(hostname);
1428 if (hostname2 == NULL)
1429 return EAI_MEMORY;
1430 /* terminate at the delimiter */
1431 hostname2[cp - hostname] = '\0';
1432 addr = hostname2;
1433 scope = cp + 1;
1434
1435 error = explore_numeric(pai, addr, servname, res, hostname, svd);
1436 if (error == 0) {
1437 u_int32_t scopeid;
1438
1439 for (cur = *res; cur; cur = cur->ai_next) {
1440 if (cur->ai_family != AF_INET6)
1441 continue;
1442 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
1443 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) {
1444 free(hostname2);
1445 return EAI_NODATA; /* XXX: is return OK? */
1446 }
1447 sin6->sin6_scope_id = scopeid;
1448 }
1449 }
1450
1451 free(hostname2);
1452
1453 return error;
1454#endif
1455}
1456
1457static int
1458get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str)
1459{
1460
1461 _DIAGASSERT(pai != NULL);
1462 _DIAGASSERT(ai != NULL);
1463 _DIAGASSERT(str != NULL);
1464
1465 if ((pai->ai_flags & AI_CANONNAME) != 0) {
1466 ai->ai_canonname = strdup(str);
1467 if (ai->ai_canonname == NULL)
1468 return EAI_MEMORY;
1469 }
1470 return 0;
1471}
1472
1473struct addrinfo *
1474allocaddrinfo(socklen_t addrlen)
1475{
1476 struct addrinfo *ai;
1477
1478 ai = calloc(sizeof(struct addrinfo) + addrlen, 1);
1479 if (ai) {
1480 ai->ai_addr = (void *)(ai+1);
1481 ai->ai_addrlen = ai->ai_addr->sa_len = addrlen;
1482 }
1483
1484 return ai;
1485}
1486
1487static struct addrinfo *
1488get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr)
1489{
1490 char *p;
1491 struct addrinfo *ai;
1492 struct sockaddr *save;
1493
1494 _DIAGASSERT(pai != NULL);
1495 _DIAGASSERT(afd != NULL);
1496 _DIAGASSERT(addr != NULL);
1497
1498 ai = allocaddrinfo((socklen_t)afd->a_socklen);
1499 if (ai == NULL)
1500 return NULL;
1501
1502 save = ai->ai_addr;
1503 memcpy(ai, pai, sizeof(struct addrinfo));
1504
1505 /* since we just overwrote all of ai, we have
1506 to restore ai_addr and ai_addrlen */
1507 ai->ai_addr = save;
1508 ai->ai_addrlen = (socklen_t)afd->a_socklen;
1509
1510 ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
1511 p = (char *)(void *)(ai->ai_addr);
1512 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen);
1513 return ai;
1514}
1515
1516static int
1517get_portmatch(const struct addrinfo *ai, const char *servname,
1518 struct servent_data *svd)
1519{
1520
1521 _DIAGASSERT(ai != NULL);
1522 /* servname may be NULL */
1523
1524 return get_port(ai, servname, 1, svd);
1525}
1526
1527static int
1528get_port(const struct addrinfo *ai, const char *servname, int matchonly,
1529 struct servent_data *svd)
1530{
1531 const char *proto;
1532 struct servent *sp;
1533 int port;
1534 int allownumeric;
1535
1536 _DIAGASSERT(ai != NULL);
1537 /* servname may be NULL */
1538
1539 if (servname == NULL)
1540 return 0;
1541 switch (ai->ai_family) {
1542 case AF_INET:
1543#ifdef AF_INET6
1544 case AF_INET6:
1545#endif
1546 break;
1547 default:
1548 return 0;
1549 }
1550
1551 switch (ai->ai_socktype) {
1552 case SOCK_RAW:
1553 return EAI_SERVICE;
1554 case SOCK_DGRAM:
1555 case SOCK_STREAM:
1556 allownumeric = 1;
1557 break;
1558 case ANY:
1559 /*
1560 * This was 0. It is now 1 so that queries specifying
1561 * a NULL hint, or hint without socktype (but, hopefully,
1562 * with protocol) and numeric address actually work.
1563 */
1564 allownumeric = 1;
1565 break;
1566 default:
1567 return EAI_SOCKTYPE;
1568 }
1569
1570 port = str2number(servname);
1571 if (port >= 0) {
1572 if (!allownumeric)
1573 return EAI_SERVICE;
1574 if (port < 0 || port > 65535)
1575 return EAI_SERVICE;
1576 port = htons(port);
1577 } else {
1578 struct servent sv;
1579 if (ai->ai_flags & AI_NUMERICSERV)
1580 return EAI_NONAME;
1581
1582 switch (ai->ai_socktype) {
1583 case SOCK_DGRAM:
1584 proto = "udp";
1585 break;
1586 case SOCK_STREAM:
1587 proto = "tcp";
1588 break;
1589 default:
1590 proto = NULL;
1591 break;
1592 }
1593
1594 sp = getservbyname_r(servname, proto, &sv, svd);
1595 if (sp == NULL)
1596 return EAI_SERVICE;
1597 port = sp->s_port;
1598 }
1599
1600 if (!matchonly)
1601 *getport(__UNCONST(ai)) = port;
1602 return 0;
1603}
1604
1605static const struct afd *
1606find_afd(int af)
1607{
1608 const struct afd *afd;
1609
1610 if (af == PF_UNSPEC)
1611 return NULL;
1612 for (afd = afdl; afd->a_af; afd++) {
1613 if (afd->a_af == af)
1614 return afd;
1615 }
1616 return NULL;
1617}
1618
1619/*
1620 * AI_ADDRCONFIG check: Build a mask containing a bit set for each address
1621 * family configured in the system.
1622 *
1623 */
1624static int
1625addrconfig(uint64_t *mask)
1626{
1627 struct ifaddrs *ifaddrs, *ifa;
1628
1629 if (getifaddrs(&ifaddrs) == -1)
1630 return -1;
1631
1632 *mask = 0;
1633 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next)
1634 if (ifa->ifa_addr && (ifa->ifa_flags & IFF_UP)) {
1635 _DIAGASSERT(ifa->ifa_addr->sa_family < 64);
1636 *mask |= (uint64_t)1 << ifa->ifa_addr->sa_family;
1637 }
1638
1639 freeifaddrs(ifaddrs);
1640 return 0;
1641}
1642
1643#ifdef INET6
1644/* convert a string to a scope identifier. XXX: IPv6 specific */
1645static int
1646ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid)
1647{
1648 u_long lscopeid;
1649 struct in6_addr *a6;
1650 char *ep;
1651
1652 _DIAGASSERT(scope != NULL);
1653 _DIAGASSERT(sin6 != NULL);
1654 _DIAGASSERT(scopeid != NULL);
1655
1656 a6 = &sin6->sin6_addr;
1657
1658 /* empty scopeid portion is invalid */
1659 if (*scope == '\0')
1660 return -1;
1661
1662 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) {
1663 /*
1664 * We currently assume a one-to-one mapping between links
1665 * and interfaces, so we simply use interface indices for
1666 * like-local scopes.
1667 */
1668 *scopeid = if_nametoindex(scope);
1669 if (*scopeid == 0)
1670 goto trynumeric;
1671 return 0;
1672 }
1673
1674 /* still unclear about literal, allow numeric only - placeholder */
1675 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
1676 goto trynumeric;
1677 if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
1678 goto trynumeric;
1679 else
1680 goto trynumeric; /* global */
1681
1682 /* try to convert to a numeric id as a last resort */
1683 trynumeric:
1684 errno = 0;
1685 lscopeid = strtoul(scope, &ep, 10);
1686 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL);
1687 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid)
1688 return 0;
1689 else
1690 return -1;
1691}
1692#endif
1693
1694/* code duplicate with gethnamaddr.c */
1695
1696static const char AskedForGot[] =
1697 "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
1698
1699#define maybe_ok(res, nm, ok) (((res)->options & RES_NOCHECKNAME) != 0U || \
1700 (ok)(nm) != 0)
1701static struct addrinfo *
1702getanswer(res_state res, const querybuf *answer, int anslen, const char *qname,
1703 int qtype, const struct addrinfo *pai)
1704{
1705 struct addrinfo sentinel, *cur;
1706 struct addrinfo ai, *aip;
1707 const struct afd *afd;
1708 char *canonname;
1709 const HEADER *hp;
1710 const u_char *cp;
1711 int n;
1712 const u_char *eom;
1713 char *bp, *ep;
1714 int type, class, ancount, qdcount;
1715 int haveanswer, had_error;
1716 char tbuf[MAXDNAME];
1717 int (*name_ok) (const char *);
1718 char hostbuf[8*1024];
1719 int port, pri, weight;
1720 struct srvinfo *srvlist, *srv, *csrv;
1721
1722 _DIAGASSERT(answer != NULL);
1723 _DIAGASSERT(qname != NULL);
1724 _DIAGASSERT(pai != NULL);
1725 _DIAGASSERT(res != NULL);
1726
1727 memset(&sentinel, 0, sizeof(sentinel));
1728 cur = &sentinel;
1729
1730 canonname = NULL;
1731 eom = answer->buf + anslen;
1732 switch (qtype) {
1733 case T_A:
1734 case T_AAAA:
1735 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/
1736 name_ok = res_hnok;
1737 break;
1738 case T_SRV:
1739 name_ok = gai_srvok;
1740 break;
1741 default:
1742 return NULL; /* XXX should be abort(); */
1743 }
1744 /*
1745 * find first satisfactory answer
1746 */
1747 hp = &answer->hdr;
1748 ancount = ntohs(hp->ancount);
1749 qdcount = ntohs(hp->qdcount);
1750 bp = hostbuf;
1751 ep = hostbuf + sizeof hostbuf;
1752 cp = answer->buf + HFIXEDSZ;
1753 if (qdcount != 1) {
1754 h_errno = NO_RECOVERY;
1755 return NULL;
1756 }
1757 n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp));
1758 if ((n < 0) || !maybe_ok(res, bp, name_ok)) {
1759 h_errno = NO_RECOVERY;
1760 return NULL;
1761 }
1762 cp += n + QFIXEDSZ;
1763 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
1764 /* res_send() has already verified that the query name is the
1765 * same as the one we sent; this just gets the expanded name
1766 * (i.e., with the succeeding search-domain tacked on).
1767 */
1768 n = (int)strlen(bp) + 1; /* for the \0 */
1769 if (n >= MAXHOSTNAMELEN) {
1770 h_errno = NO_RECOVERY;
1771 return NULL;
1772 }
1773 canonname = bp;
1774 bp += n;
1775 /* The qname can be abbreviated, but h_name is now absolute. */
1776 qname = canonname;
1777 }
1778 haveanswer = 0;
1779 had_error = 0;
1780 srvlist = NULL;
1781 while (ancount-- > 0 && cp < eom && !had_error) {
1782 n = dn_expand(answer->buf, eom, cp, bp, (int)(ep - bp));
1783 if ((n < 0) || !maybe_ok(res, bp, name_ok)) {
1784 had_error++;
1785 continue;
1786 }
1787 cp += n; /* name */
1788 type = _getshort(cp);
1789 cp += INT16SZ; /* type */
1790 class = _getshort(cp);
1791 cp += INT16SZ + INT32SZ; /* class, TTL */
1792 n = _getshort(cp);
1793 cp += INT16SZ; /* len */
1794 if (class != C_IN) {
1795 /* XXX - debug? syslog? */
1796 cp += n;
1797 continue; /* XXX - had_error++ ? */
1798 }
1799 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
1800 type == T_CNAME) {
1801 n = dn_expand(answer->buf, eom, cp, tbuf, (int)sizeof tbuf);
1802 if ((n < 0) || !maybe_ok(res, tbuf, name_ok)) {
1803 had_error++;
1804 continue;
1805 }
1806 cp += n;
1807 /* Get canonical name. */
1808 n = (int)strlen(tbuf) + 1; /* for the \0 */
1809 if (n > ep - bp || n >= MAXHOSTNAMELEN) {
1810 had_error++;
1811 continue;
1812 }
1813 strlcpy(bp, tbuf, (size_t)(ep - bp));
1814 canonname = bp;
1815 bp += n;
1816 continue;
1817 }
1818 if (qtype == T_ANY) {
1819 if (!(type == T_A || type == T_AAAA)) {
1820 cp += n;
1821 continue;
1822 }
1823 } else if (type != qtype) {
1824 if (type != T_KEY && type != T_SIG) {
1825 struct syslog_data sd = SYSLOG_DATA_INIT;
1826 syslog_r(LOG_NOTICE|LOG_AUTH, &sd,
1827 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
1828 qname, p_class(C_IN), p_type(qtype),
1829 p_type(type));
1830 }
1831 cp += n;
1832 continue; /* XXX - had_error++ ? */
1833 }
1834 switch (type) {
1835 case T_A:
1836 case T_AAAA:
1837 if (strcasecmp(canonname, bp) != 0) {
1838 struct syslog_data sd = SYSLOG_DATA_INIT;
1839 syslog_r(LOG_NOTICE|LOG_AUTH, &sd,
1840 AskedForGot, canonname, bp);
1841 cp += n;
1842 continue; /* XXX - had_error++ ? */
1843 }
1844 if (type == T_A && n != INADDRSZ) {
1845 cp += n;
1846 continue;
1847 }
1848 if (type == T_AAAA && n != IN6ADDRSZ) {
1849 cp += n;
1850 continue;
1851 }
1852 if (type == T_AAAA) {
1853 struct in6_addr in6;
1854 memcpy(&in6, cp, IN6ADDRSZ);
1855 if (IN6_IS_ADDR_V4MAPPED(&in6)) {
1856 cp += n;
1857 continue;
1858 }
1859 }
1860 if (!haveanswer) {
1861 int nn;
1862
1863 canonname = bp;
1864 nn = (int)strlen(bp) + 1; /* for the \0 */
1865 bp += nn;
1866 }
1867
1868 /* don't overwrite pai */
1869 ai = *pai;
1870 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
1871 afd = find_afd(ai.ai_family);
1872 if (afd == NULL) {
1873 cp += n;
1874 continue;
1875 }
1876 cur->ai_next = get_ai(&ai, afd, (const char *)cp);
1877 if (cur->ai_next == NULL)
1878 had_error++;
1879 while (cur && cur->ai_next)
1880 cur = cur->ai_next;
1881 cp += n;
1882 break;
1883 case T_SRV:
1884 /* Add to SRV list. Insertion sort on priority. */
1885 pri = _getshort(cp);
1886 cp += INT16SZ;
1887 weight = _getshort(cp);
1888 cp += INT16SZ;
1889 port = _getshort(cp);
1890 cp += INT16SZ;
1891 n = dn_expand(answer->buf, eom, cp, tbuf,
1892 (int)sizeof(tbuf));
1893 if ((n < 0) || !maybe_ok(res, tbuf, res_hnok)) {
1894 had_error++;
1895 continue;
1896 }
1897 cp += n;
1898 if (strlen(tbuf) + 1 >= MAXDNAME) {
1899 had_error++;
1900 continue;
1901 }
1902 srv = malloc(sizeof(*srv));
1903 if (!srv) {
1904 had_error++;
1905 continue;
1906 }
1907 strlcpy(srv->name, tbuf, sizeof(srv->name));
1908 srv->pri = pri;
1909 srv->weight = weight;
1910 srv->port = port;
1911 /* Weight 0 is sorted before other weights. */
1912 if (!srvlist
1913 || srv->pri < srvlist->pri
1914 || (srv->pri == srvlist->pri &&
1915 (!srv->weight || srvlist->weight))) {
1916 srv->next = srvlist;
1917 srvlist = srv;
1918 } else {
1919 for (csrv = srvlist;
1920 csrv->next && csrv->next->pri <= srv->pri;
1921 csrv = csrv->next) {
1922 if (csrv->next->pri == srv->pri
1923 && (!srv->weight ||
1924 csrv->next->weight))
1925 break;
1926 }
1927 srv->next = csrv->next;
1928 csrv->next = srv;
1929 }
1930 continue; /* Don't add to haveanswer yet. */
1931 default:
1932 abort();
1933 }
1934 if (!had_error)
1935 haveanswer++;
1936 }
1937
1938 if (srvlist) {
1939 /*
1940 * Check for explicit rejection.
1941 */
1942 if (!srvlist->next && !srvlist->name[0]) {
1943 free(srvlist);
1944 h_errno = HOST_NOT_FOUND;
1945 return NULL;
1946 }
1947
1948 while (srvlist) {
1949 struct res_target q, q2;
1950
1951 srv = srvlist;
1952 srvlist = srvlist->next;
1953
1954 /*
1955 * Since res_* doesn't give the additional
1956 * section, we always look up.
1957 */
1958 memset(&q, 0, sizeof(q));
1959 memset(&q2, 0, sizeof(q2));
1960
1961 q.name = srv->name;
1962 q.qclass = C_IN;
1963 q.qtype = T_AAAA;
1964 q.next = &q2;
1965 q2.name = srv->name;
1966 q2.qclass = C_IN;
1967 q2.qtype = T_A;
1968
1969 aip = _dns_query(&q, pai, res, 0);
1970
1971 if (aip != NULL) {
1972 cur->ai_next = aip;
1973 while (cur && cur->ai_next) {
1974 cur = cur->ai_next;
1975 *getport(cur) = htons(srv->port);
1976 haveanswer++;
1977 }
1978 }
1979 free(srv);
1980 }
1981 }
1982 if (haveanswer) {
1983 if (!sentinel.ai_next->ai_canonname)
1984 (void)get_canonname(pai, sentinel.ai_next,
1985 canonname ? canonname : qname);
1986 h_errno = NETDB_SUCCESS;
1987 return sentinel.ai_next;
1988 }
1989
1990 /* We could have walked a CNAME chain, */
1991 /* but the ultimate target may not have what we looked for */
1992 h_errno = ntohs(hp->ancount) > 0? NO_DATA : NO_RECOVERY;
1993 return NULL;
1994}
1995
1996#define SORTEDADDR(p) (((struct sockaddr_in *)(void *)(p->ai_next->ai_addr))->sin_addr.s_addr)
1997#define SORTMATCH(p, s) ((SORTEDADDR(p) & (s).mask) == (s).addr.s_addr)
1998
1999static void
2000aisort(struct addrinfo *s, res_state res)
2001{
2002 struct addrinfo head, *t, *p;
2003 int i;
2004
2005 head.ai_next = NULL;
2006 t = &head;
2007
2008 for (i = 0; i < res->nsort; i++) {
2009 p = s;
2010 while (p->ai_next) {
2011 if ((p->ai_next->ai_family != AF_INET)
2012 || SORTMATCH(p, res->sort_list[i])) {
2013 t->ai_next = p->ai_next;
2014 t = t->ai_next;
2015 p->ai_next = p->ai_next->ai_next;
2016 } else {
2017 p = p->ai_next;
2018 }
2019 }
2020 }
2021
2022 /* add rest of list and reset s to the new list*/
2023 t->ai_next = s->ai_next;
2024 s->ai_next = head.ai_next;
2025}
2026
2027static struct addrinfo *
2028_dns_query(struct res_target *q, const struct addrinfo *pai,
2029 res_state res, int dosearch)
2030{
2031 struct res_target *q2 = q->next;
2032 querybuf *buf, *buf2;
2033 struct addrinfo sentinel, *cur, *ai;
2034
2035#ifdef DNS_DEBUG
2036 struct res_target *iter;
2037 for (iter = q; iter; iter = iter->next)
2038 printf("Query type %d for %s\n", iter->qtype, iter->name);
2039#endif
2040
2041 buf = malloc(sizeof(*buf));
2042 if (buf == NULL) {
2043 h_errno = NETDB_INTERNAL;
2044 return NULL;
2045 }
2046 buf2 = malloc(sizeof(*buf2));
2047 if (buf2 == NULL) {
2048 free(buf);
2049 h_errno = NETDB_INTERNAL;
2050 return NULL;
2051 }
2052
2053 memset(&sentinel, 0, sizeof(sentinel));
2054 cur = &sentinel;
2055
2056 q->answer = buf->buf;
2057 q->anslen = sizeof(buf->buf);
2058 if (q2) {
2059 q2->answer = buf2->buf;
2060 q2->anslen = sizeof(buf2->buf);
2061 }
2062
2063 if (dosearch) {
2064 if (res_searchN(q->name, q, res) < 0)
2065 goto out;
2066 } else {
2067 if (res_queryN(q->name, q, res) < 0)
2068 goto out;
2069 }
2070
2071 ai = getanswer(res, buf, q->n, q->name, q->qtype, pai);
2072 if (ai) {
2073 cur->ai_next = ai;
2074 while (cur && cur->ai_next)
2075 cur = cur->ai_next;
2076 }
2077 if (q2) {
2078 ai = getanswer(res, buf2, q2->n, q2->name, q2->qtype, pai);
2079 if (ai)
2080 cur->ai_next = ai;
2081 }
2082 free(buf);
2083 free(buf2);
2084 return sentinel.ai_next;
2085out:
2086 free(buf);
2087 free(buf2);
2088 return NULL;
2089}
2090
2091/*ARGSUSED*/
2092static struct addrinfo *
2093_dns_srv_lookup(const char *name, const char *servname,
2094 const struct addrinfo *pai)
2095{
2096 static const char * const srvprotos[] = { "tcp", "udp" };
2097 static const int srvnottype[] = { SOCK_DGRAM, SOCK_STREAM };
2098 static const int nsrvprotos = 2;
2099 struct addrinfo sentinel, *cur, *ai;
2100 struct servent *serv, sv;
2101 struct servent_data svd;
2102 struct res_target q;
2103 res_state res;
2104 char *tname;
2105 int i;
2106
2107 res = __res_get_state();
2108 if (res == NULL)
2109 return NULL;
2110
2111 memset(&svd, 0, sizeof(svd));
2112 memset(&sentinel, 0, sizeof(sentinel));
2113 cur = &sentinel;
2114
2115 /*
2116 * Iterate over supported SRV protocols.
2117 * (currently UDP and TCP only)
2118 */
2119 for (i = 0; i < nsrvprotos; i++) {
2120 /*
2121 * Check that the caller didn't specify a hint
2122 * which precludes this protocol.
2123 */
2124 if (pai->ai_socktype == srvnottype[i])
2125 continue;
2126 /*
2127 * If the caller specified a port,
2128 * then lookup the database for the
2129 * official service name.
2130 */
2131 serv = getservbyname_r(servname, srvprotos[i], &sv, &svd);
2132 if (serv == NULL)
2133 continue;
2134
2135 /*
2136 * Construct service DNS name.
2137 */
2138 if (asprintf(&tname, "_%s._%s.%s", serv->s_name, serv->s_proto,
2139 name) < 0)
2140 continue;
2141
2142 memset(&q, 0, sizeof(q));
2143 q.name = tname;
2144 q.qclass = C_IN;
2145 q.qtype = T_SRV;
2146
2147 /*
2148 * Do SRV query.
2149 */
2150 ai = _dns_query(&q, pai, res, 1);
2151 if (ai) {
2152 cur->ai_next = ai;
2153 while (cur && cur->ai_next)
2154 cur = cur->ai_next;
2155 }
2156 free(tname);
2157 }
2158
2159 if (res->nsort)
2160 aisort(&sentinel, res);
2161
2162 __res_put_state(res);
2163
2164 return sentinel.ai_next;
2165}
2166
2167/*ARGSUSED*/
2168static struct addrinfo *
2169_dns_host_lookup(const char *name, const struct addrinfo *pai)
2170{
2171 struct res_target q, q2;
2172 struct addrinfo sentinel, *ai;
2173 res_state res;
2174
2175 res = __res_get_state();
2176 if (res == NULL)
2177 return NULL;
2178
2179 memset(&q, 0, sizeof(q2));
2180 memset(&q2, 0, sizeof(q2));
2181
2182 switch (pai->ai_family) {
2183 case AF_UNSPEC:
2184 /* prefer IPv6 */
2185 q.name = name;
2186 q.qclass = C_IN;
2187 q.qtype = T_AAAA;
2188 q.next = &q2;
2189 q2.name = name;
2190 q2.qclass = C_IN;
2191 q2.qtype = T_A;
2192 break;
2193 case AF_INET:
2194 q.name = name;
2195 q.qclass = C_IN;
2196 q.qtype = T_A;
2197 break;
2198 case AF_INET6:
2199 q.name = name;
2200 q.qclass = C_IN;
2201 q.qtype = T_AAAA;
2202 break;
2203 default:
2204 __res_put_state(res);
2205 h_errno = NETDB_INTERNAL;
2206 return NULL;
2207 }
2208
2209 ai = _dns_query(&q, pai, res, 1);
2210
2211 memset(&sentinel, 0, sizeof(sentinel));
2212 sentinel.ai_next = ai;
2213
2214 if (ai != NULL && res->nsort)
2215 aisort(&sentinel, res);
2216
2217 __res_put_state(res);
2218
2219 return sentinel.ai_next;
2220}
2221
2222/*ARGSUSED*/
2223static int
2224_dns_getaddrinfo(void *rv, void *cb_data, va_list ap)
2225{
2226 struct addrinfo *ai = NULL;
2227 const char *name, *servname;
2228 const struct addrinfo *pai;
2229
2230 name = va_arg(ap, char *);
2231 pai = va_arg(ap, const struct addrinfo *);
2232 servname = va_arg(ap, char *);
2233
2234 /*
2235 * Try doing SRV lookup on service first.
2236 */
2237 if (servname
2238#ifdef AI_SRV
2239 && (pai->ai_flags & AI_SRV)
2240#endif
2241 && !(pai->ai_flags & AI_NUMERICSERV)
2242 && str2number(servname) == -1) {
2243
2244#ifdef DNS_DEBUG
2245 printf("%s: try SRV lookup\n", __func__);
2246#endif
2247 ai = _dns_srv_lookup(name, servname, pai);
2248 }
2249
2250 /*
2251 * Do lookup on name.
2252 */
2253 if (ai == NULL) {
2254
2255#ifdef DNS_DEBUG
2256 printf("%s: try HOST lookup\n", __func__);
2257#endif
2258 ai = _dns_host_lookup(name, pai);
2259
2260 if (ai == NULL) {
2261 switch (h_errno) {
2262 case HOST_NOT_FOUND:
2263 case NO_DATA: // XXX: Perhaps we could differentiate
2264 // So that we could return EAI_NODATA?
2265 return NS_NOTFOUND;
2266 case TRY_AGAIN:
2267 return NS_TRYAGAIN;
2268 default:
2269 return NS_UNAVAIL;
2270 }
2271 }
2272 }
2273
2274 *((struct addrinfo **)rv) = ai;
2275 return NS_SUCCESS;
2276}
2277
2278static void
2279_sethtent(FILE **hostf)
2280{
2281
2282 if (!*hostf)
2283 *hostf = fopen(_PATH_HOSTS, "re");
2284 else
2285 rewind(*hostf);
2286}
2287
2288static void
2289_endhtent(FILE **hostf)
2290{
2291
2292 if (*hostf) {
2293 (void) fclose(*hostf);
2294 *hostf = NULL;
2295 }
2296}
2297
2298static struct addrinfo *
2299_gethtent(FILE **hostf, const char *name, const struct addrinfo *pai)
2300{
2301 char *p;
2302 char *cp, *tname, *cname;
2303 struct addrinfo hints, *res0, *res;
2304 int error;
2305 const char *addr;
2306 char hostbuf[8*1024];
2307
2308 _DIAGASSERT(name != NULL);
2309 _DIAGASSERT(pai != NULL);
2310
2311 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "re")))
2312 return NULL;
2313 again:
2314 if (!(p = fgets(hostbuf, (int)sizeof hostbuf, *hostf)))
2315 return NULL;
2316 if (*p == '#')
2317 goto again;
2318 if (!(cp = strpbrk(p, "#\n")))
2319 goto again;
2320 *cp = '\0';
2321 if (!(cp = strpbrk(p, " \t")))
2322 goto again;
2323 *cp++ = '\0';
2324 addr = p;
2325 /* if this is not something we're looking for, skip it. */
2326 cname = NULL;
2327 while (cp && *cp) {
2328 if (*cp == ' ' || *cp == '\t') {
2329 cp++;
2330 continue;
2331 }
2332 if (!cname)
2333 cname = cp;
2334 tname = cp;
2335 if ((cp = strpbrk(cp, " \t")) != NULL)
2336 *cp++ = '\0';
2337 if (strcasecmp(name, tname) == 0)
2338 goto found;
2339 }
2340 goto again;
2341
2342found:
2343 hints = *pai;
2344 hints.ai_flags = AI_NUMERICHOST;
2345 error = getaddrinfo(addr, NULL, &hints, &res0);
2346 if (error)
2347 goto again;
2348 for (res = res0; res; res = res->ai_next) {
2349 /* cover it up */
2350 res->ai_flags = pai->ai_flags;
2351
2352 if (pai->ai_flags & AI_CANONNAME) {
2353 if (get_canonname(pai, res, cname) != 0) {
2354 freeaddrinfo(res0);
2355 goto again;
2356 }
2357 }
2358 }
2359 return res0;
2360}
2361
2362/*ARGSUSED*/
2363static int
2364_files_getaddrinfo(void *rv, void *cb_data, va_list ap)
2365{
2366 const char *name;
2367 const struct addrinfo *pai;
2368 struct addrinfo sentinel, *cur;
2369 struct addrinfo *p;
2370#ifndef _REENTRANT
2371 static
2372#endif
2373 FILE *hostf = NULL;
2374
2375 name = va_arg(ap, char *);
2376 pai = va_arg(ap, const struct addrinfo *);
2377
2378 memset(&sentinel, 0, sizeof(sentinel));
2379 cur = &sentinel;
2380
2381 _sethtent(&hostf);
2382 while ((p = _gethtent(&hostf, name, pai)) != NULL) {
2383 cur->ai_next = p;
2384 while (cur && cur->ai_next)
2385 cur = cur->ai_next;
2386 }
2387 _endhtent(&hostf);
2388
2389 *((struct addrinfo **)rv) = sentinel.ai_next;
2390 if (sentinel.ai_next == NULL)
2391 return NS_NOTFOUND;
2392 return NS_SUCCESS;
2393}
2394
2395#ifdef YP
2396/*ARGSUSED*/
2397static struct addrinfo *
2398_yphostent(char *line, const struct addrinfo *pai)
2399{
2400 struct addrinfo sentinel, *cur;
2401 struct addrinfo hints, *res, *res0;
2402 int error;
2403 char *p;
2404 const char *addr, *canonname;
2405 char *nextline;
2406 char *cp;
2407
2408 _DIAGASSERT(line != NULL);
2409 _DIAGASSERT(pai != NULL);
2410
2411 p = line;
2412 addr = canonname = NULL;
2413
2414 memset(&sentinel, 0, sizeof(sentinel));
2415 cur = &sentinel;
2416
2417nextline:
2418 /* terminate line */
2419 cp = strchr(p, '\n');
2420 if (cp) {
2421 *cp++ = '\0';
2422 nextline = cp;
2423 } else
2424 nextline = NULL;
2425
2426 cp = strpbrk(p, " \t");
2427 if (cp == NULL) {
2428 if (canonname == NULL)
2429 return NULL;
2430 else
2431 goto done;
2432 }
2433 *cp++ = '\0';
2434
2435 addr = p;
2436
2437 while (cp && *cp) {
2438 if (*cp == ' ' || *cp == '\t') {
2439 cp++;
2440 continue;
2441 }
2442 if (!canonname)
2443 canonname = cp;
2444 if ((cp = strpbrk(cp, " \t")) != NULL)
2445 *cp++ = '\0';
2446 }
2447
2448 hints = *pai;
2449 hints.ai_flags = AI_NUMERICHOST;
2450 error = getaddrinfo(addr, NULL, &hints, &res0);
2451 if (error == 0) {
2452 for (res = res0; res; res = res->ai_next) {
2453 /* cover it up */
2454 res->ai_flags = pai->ai_flags;
2455
2456 if (pai->ai_flags & AI_CANONNAME)
2457 (void)get_canonname(pai, res, canonname);
2458 }
2459 } else
2460 res0 = NULL;
2461 if (res0) {
2462 cur->ai_next = res0;
2463 while (cur->ai_next)
2464 cur = cur->ai_next;
2465 }
2466
2467 if (nextline) {
2468 p = nextline;
2469 goto nextline;
2470 }
2471
2472done:
2473 return sentinel.ai_next;
2474}
2475
2476/*ARGSUSED*/
2477static int
2478_yp_getaddrinfo(void *rv, void *cb_data, va_list ap)
2479{
2480 struct addrinfo sentinel, *cur;
2481 struct addrinfo *ai = NULL;
2482 char *ypbuf;
2483 int ypbuflen, r;
2484 const char *name;
2485 const struct addrinfo *pai;
2486 char *ypdomain;
2487
2488 if (_yp_check(&ypdomain) == 0)
2489 return NS_UNAVAIL;
2490
2491 name = va_arg(ap, char *);
2492 pai = va_arg(ap, const struct addrinfo *);
2493
2494 memset(&sentinel, 0, sizeof(sentinel));
2495 cur = &sentinel;
2496
2497 /* hosts.byname is only for IPv4 (Solaris8) */
2498 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) {
2499 r = yp_match(ypdomain, "hosts.byname", name,
2500 (int)strlen(name), &ypbuf, &ypbuflen);
2501 if (r == 0) {
2502 struct addrinfo ai4;
2503
2504 ai4 = *pai;
2505 ai4.ai_family = AF_INET;
2506 ai = _yphostent(ypbuf, &ai4);
2507 if (ai) {
2508 cur->ai_next = ai;
2509 while (cur && cur->ai_next)
2510 cur = cur->ai_next;
2511 }
2512 }
2513 free(ypbuf);
2514 }
2515
2516 /* ipnodes.byname can hold both IPv4/v6 */
2517 r = yp_match(ypdomain, "ipnodes.byname", name,
2518 (int)strlen(name), &ypbuf, &ypbuflen);
2519 if (r == 0) {
2520 ai = _yphostent(ypbuf, pai);
2521 if (ai)
2522 cur->ai_next = ai;
2523 free(ypbuf);
2524 }
2525
2526 if (sentinel.ai_next == NULL) {
2527 h_errno = HOST_NOT_FOUND;
2528 return NS_NOTFOUND;
2529 }
2530 *((struct addrinfo **)rv) = sentinel.ai_next;
2531 return NS_SUCCESS;
2532}
2533#endif
2534
2535/* resolver logic */
2536
2537/*
2538 * Formulate a normal query, send, and await answer.
2539 * Returned answer is placed in supplied buffer "answer".
2540 * Perform preliminary check of answer, returning success only
2541 * if no error is indicated and the answer count is nonzero.
2542 * Return the size of the response on success, -1 on error.
2543 * Error number is left in h_errno.
2544 *
2545 * Caller must parse answer and determine whether it answers the question.
2546 */
2547static int
2548res_queryN(const char *name, /* domain name */ struct res_target *target,
2549 res_state statp)
2550{
2551 u_char buf[MAXPACKET];
2552 HEADER *hp;
2553 int n;
2554 struct res_target *t;
2555 int rcode;
2556 u_char *rdata;
2557 int ancount;
2558
2559 _DIAGASSERT(name != NULL);
2560 /* XXX: target may be NULL??? */
2561
2562 rcode = NOERROR;
2563 ancount = 0;
2564
2565 for (t = target; t; t = t->next) {
2566 int class, type;
2567 u_char *answer;
2568 int anslen;
2569 u_int oflags;
2570
2571 hp = (HEADER *)(void *)t->answer;
2572 oflags = statp->_flags;
2573
2574again:
2575 hp->rcode = NOERROR; /* default */
2576
2577 /* make it easier... */
2578 class = t->qclass;
2579 type = t->qtype;
2580 answer = t->answer;
2581 anslen = t->anslen;
2582#ifdef DEBUG
2583 if (statp->options & RES_DEBUG)
2584 printf(";; res_nquery(%s, %d, %d)\n", name, class, type);
2585#endif
2586
2587 n = res_nmkquery(statp, QUERY, name, class, type, NULL, 0, NULL,
2588 buf, (int)sizeof(buf));
2589#ifdef RES_USE_EDNS0
2590 if (n > 0 && (statp->_flags & RES_F_EDNS0ERR) == 0 &&
2591 (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0) {
2592 n = res_nopt(statp, n, buf, (int)sizeof(buf), anslen);
2593 rdata = &buf[n];
2594 if (n > 0 && (statp->options & RES_NSID) != 0U) {
2595 n = res_nopt_rdata(statp, n, buf,
2596 (int)sizeof(buf),
2597 rdata, NS_OPT_NSID, 0, NULL);
2598 }
2599 }
2600#endif
2601 if (n <= 0) {
2602#ifdef DEBUG
2603 if (statp->options & RES_DEBUG)
2604 printf(";; res_nquery: mkquery failed\n");
2605#endif
2606 h_errno = NO_RECOVERY;
2607 return n;
2608 }
2609 n = res_nsend(statp, buf, n, answer, anslen);
2610 if (n < 0) {
2611#ifdef RES_USE_EDNS0
2612 /* if the query choked with EDNS0, retry without EDNS0 */
2613 if ((statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U &&
2614 ((oflags ^ statp->_flags) & RES_F_EDNS0ERR) != 0) {
2615 statp->_flags |= RES_F_EDNS0ERR;
2616 if (statp->options & RES_DEBUG)
2617 printf(";; res_nquery: retry without EDNS0\n");
2618 goto again;
2619 }
2620#endif
2621#if 0
2622#ifdef DEBUG
2623 if (statp->options & RES_DEBUG)
2624 printf(";; res_query: send error\n");
2625#endif
2626 h_errno = TRY_AGAIN;
2627 return n;
2628#endif
2629 }
2630
2631 if (n < 0 || hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
2632 rcode = hp->rcode; /* record most recent error */
2633#ifdef DEBUG
2634 if (statp->options & RES_DEBUG)
2635 printf(";; rcode = (%s), counts = an:%d ns:%d ar:%d\n",
2636 p_rcode(hp->rcode),
2637 ntohs(hp->ancount),
2638 ntohs(hp->nscount),
2639 ntohs(hp->arcount));
2640#endif
2641 continue;
2642 }
2643
2644 ancount += ntohs(hp->ancount);
2645
2646 t->n = n;
2647 }
2648
2649 if (ancount == 0) {
2650 switch (rcode) {
2651 case NXDOMAIN:
2652 h_errno = HOST_NOT_FOUND;
2653 break;
2654 case SERVFAIL:
2655 h_errno = TRY_AGAIN;
2656 break;
2657 case NOERROR:
2658 h_errno = NO_DATA;
2659 break;
2660 case FORMERR:
2661 case NOTIMP:
2662 case REFUSED:
2663 default:
2664 h_errno = NO_RECOVERY;
2665 break;
2666 }
2667 return -1;
2668 }
2669 return ancount;
2670}
2671
2672/*
2673 * Formulate a normal query, send, and retrieve answer in supplied buffer.
2674 * Return the size of the response on success, -1 on error.
2675 * If enabled, implement search rules until answer or unrecoverable failure
2676 * is detected. Error code, if any, is left in h_errno.
2677 */
2678static int
2679res_searchN(const char *name, struct res_target *target, res_state res)
2680{
2681 const char *cp, * const *domain;
2682 HEADER *hp;
2683 u_int dots;
2684 char buf[MAXHOSTNAMELEN];
2685 int trailing_dot, ret, saved_herrno;
2686 int got_nodata = 0, got_servfail = 0, tried_as_is = 0;
2687
2688 _DIAGASSERT(name != NULL);
2689 _DIAGASSERT(target != NULL);
2690
2691 hp = (HEADER *)(void *)target->answer; /*XXX*/
2692
2693 errno = 0;
2694 h_errno = HOST_NOT_FOUND; /* default, if we never query */
2695 dots = 0;
2696 for (cp = name; *cp; cp++)
2697 dots += (*cp == '.');
2698 trailing_dot = 0;
2699 if (cp > name && *--cp == '.')
2700 trailing_dot++;
2701
2702 /*
2703 * if there aren't any dots, it could be a user-level alias
2704 */
2705 if (!dots && (cp = res_hostalias(res, name, buf, sizeof(buf))) != NULL) {
2706 ret = res_queryN(cp, target, res);
2707 return ret;
2708 }
2709
2710 /*
2711 * If there are dots in the name already, let's just give it a try
2712 * 'as is'. The threshold can be set with the "ndots" option.
2713 */
2714 saved_herrno = -1;
2715 if (dots >= res->ndots) {
2716 ret = res_querydomainN(name, NULL, target, res);
2717 if (ret > 0)
2718 return ret;
2719 saved_herrno = h_errno;
2720 tried_as_is++;
2721 }
2722
2723 /*
2724 * We do at least one level of search if
2725 * - there is no dot and RES_DEFNAME is set, or
2726 * - there is at least one dot, there is no trailing dot,
2727 * and RES_DNSRCH is set.
2728 */
2729 if ((!dots && (res->options & RES_DEFNAMES)) ||
2730 (dots && !trailing_dot && (res->options & RES_DNSRCH))) {
2731 int done = 0;
2732
2733 for (domain = (const char * const *)res->dnsrch;
2734 *domain && !done;
2735 domain++) {
2736
2737 ret = res_querydomainN(name, *domain, target, res);
2738 if (ret > 0)
2739 return ret;
2740
2741 /*
2742 * If no server present, give up.
2743 * If name isn't found in this domain,
2744 * keep trying higher domains in the search list
2745 * (if that's enabled).
2746 * On a NO_DATA error, keep trying, otherwise
2747 * a wildcard entry of another type could keep us
2748 * from finding this entry higher in the domain.
2749 * If we get some other error (negative answer or
2750 * server failure), then stop searching up,
2751 * but try the input name below in case it's
2752 * fully-qualified.
2753 */
2754 if (errno == ECONNREFUSED) {
2755 h_errno = TRY_AGAIN;
2756 return -1;
2757 }
2758
2759 switch (h_errno) {
2760 case NO_DATA:
2761 got_nodata++;
2762 /* FALLTHROUGH */
2763 case HOST_NOT_FOUND:
2764 /* keep trying */
2765 break;
2766 case TRY_AGAIN:
2767 if (hp->rcode == SERVFAIL) {
2768 /* try next search element, if any */
2769 got_servfail++;
2770 break;
2771 }
2772 /* FALLTHROUGH */
2773 default:
2774 /* anything else implies that we're done */
2775 done++;
2776 }
2777 /*
2778 * if we got here for some reason other than DNSRCH,
2779 * we only wanted one iteration of the loop, so stop.
2780 */
2781 if (!(res->options & RES_DNSRCH))
2782 done++;
2783 }
2784 }
2785
2786 /*
2787 * if we have not already tried the name "as is", do that now.
2788 * note that we do this regardless of how many dots were in the
2789 * name or whether it ends with a dot.
2790 */
2791 if (!tried_as_is) {
2792 ret = res_querydomainN(name, NULL, target, res);
2793 if (ret > 0)
2794 return ret;
2795 }
2796
2797 /*
2798 * if we got here, we didn't satisfy the search.
2799 * if we did an initial full query, return that query's h_errno
2800 * (note that we wouldn't be here if that query had succeeded).
2801 * else if we ever got a nodata, send that back as the reason.
2802 * else send back meaningless h_errno, that being the one from
2803 * the last DNSRCH we did.
2804 */
2805 if (saved_herrno != -1)
2806 h_errno = saved_herrno;
2807 else if (got_nodata)
2808 h_errno = NO_DATA;
2809 else if (got_servfail)
2810 h_errno = TRY_AGAIN;
2811 return -1;
2812}
2813
2814/*
2815 * Perform a call on res_query on the concatenation of name and domain,
2816 * removing a trailing dot from name if domain is NULL.
2817 */
2818static int
2819res_querydomainN(const char *name, const char *domain,
2820 struct res_target *target, res_state res)
2821{
2822 char nbuf[MAXDNAME];
2823 const char *longname = nbuf;
2824 size_t n, d;
2825
2826 _DIAGASSERT(name != NULL);
2827 /* XXX: target may be NULL??? */
2828
2829#ifdef DEBUG
2830 if (res->options & RES_DEBUG)
2831 printf(";; res_querydomain(%s, %s)\n",
2832 name, domain?domain:"<Nil>");
2833#endif
2834 if (domain == NULL) {
2835 /*
2836 * Check for trailing '.';
2837 * copy without '.' if present.
2838 */
2839 n = strlen(name);
2840 if (n + 1 > sizeof(nbuf)) {
2841 h_errno = NO_RECOVERY;
2842 return -1;
2843 }
2844 if (n > 0 && name[--n] == '.') {
2845 strncpy(nbuf, name, n);
2846 nbuf[n] = '\0';
2847 } else
2848 longname = name;
2849 } else {
2850 n = strlen(name);
2851 d = strlen(domain);
2852 if (n + 1 + d + 1 > sizeof(nbuf)) {
2853 h_errno = NO_RECOVERY;
2854 return -1;
2855 }
2856 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain);
2857 }
2858 return res_queryN(longname, target, res);
2859}
2860
2861#ifdef TEST
2862int
2863main(int argc, char *argv[]) {
2864 struct addrinfo *ai, *sai;
2865 int i, e;
2866 char buf[1024];
2867
2868 for (i = 1; i < argc; i++) {
2869 if ((e = getaddrinfo(argv[i], NULL, NULL, &sai)) != 0)
2870 warnx("%s: %s", argv[i], gai_strerror(e));
2871 for (ai = sai; ai; ai = ai->ai_next) {
2872 sockaddr_snprintf(buf, sizeof(buf), "%a", ai->ai_addr);
2873 printf("flags=0x%x family=%d socktype=%d protocol=%d "
2874 "addrlen=%zu addr=%s canonname=%s next=%p\n",
2875 ai->ai_flags,
2876 ai->ai_family,
2877 ai->ai_socktype,
2878 ai->ai_protocol,
2879 (size_t)ai->ai_addrlen,
2880 buf,
2881 ai->ai_canonname,
2882 ai->ai_next);
2883 }
2884 if (sai)
2885 freeaddrinfo(sai);
2886 }
2887 return 0;
2888}
2889#endif
2890