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i386 removal, part 68/x: Remove a number of obsolete Makefiles from gnu/.
[dragonfly.git] / lib / libc / net / getaddrinfo.c
blob227d2cee8d0b5e910ef9284394c9d19ebd1024b2
1 /* $FreeBSD: src/lib/libc/net/getaddrinfo.c,v 1.87 2008/02/03 19:07:55 ume Exp $ */
2 /* $KAME: getaddrinfo.c,v 1.15 2000/07/09 04:37:24 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 * - freeaddrinfo(NULL). RFC2553 is silent about it. XNET 5.2 says it is
39 * invalid. current code - SEGV on freeaddrinfo(NULL)
40 *
41 * Note:
42 * - The code filters out AFs that are not supported by the kernel,
43 * when globbing NULL hostname (to loopback, or wildcard). Is it the right
44 * thing to do? What is the relationship with post-RFC2553 AI_ADDRCONFIG
45 * in ai_flags?
46 * - (post-2553) semantics of AI_ADDRCONFIG itself is too vague.
47 * (1) what should we do against numeric hostname (2) what should we do
48 * against NULL hostname (3) what is AI_ADDRCONFIG itself. AF not ready?
49 * non-loopback address configured? global address configured?
50 */
51
52 #include "namespace.h"
53 #include <sys/types.h>
54 #include <sys/param.h>
55 #include <sys/socket.h>
56 #include <net/if.h>
57 #include <netinet/in.h>
58 #include <sys/queue.h>
59 #ifdef INET6
60 #include <net/if_var.h>
61 #include <sys/sysctl.h>
62 #include <sys/ioctl.h>
63 #include <netinet6/in6_var.h> /* XXX */
64 #endif
65 #include <arpa/inet.h>
66 #include <arpa/nameser.h>
67 #include <rpc/rpc.h>
68 #include <rpcsvc/yp_prot.h>
69 #include <rpcsvc/ypclnt.h>
70 #include <netdb.h>
71 #include <resolv.h>
72 #include <string.h>
73 #include <stdlib.h>
74 #include <stddef.h>
75 #include <ctype.h>
76 #include <unistd.h>
77 #include <stdio.h>
78 #include <errno.h>
79
80 #include "res_config.h"
81
82 #ifdef DEBUG
83 #include <syslog.h>
84 #endif
85
86 #include <stdarg.h>
87 #include <nsswitch.h>
88 #include "un-namespace.h"
89 #include "libc_private.h"
90 #ifdef NS_CACHING
91 #include "nscache.h"
92 #endif
93
94 #define SUCCESS 0
95 #define ANY 0
96 #define YES 1
97 #define NO 0
98
99 static const char in_addrany[] = { 0, 0, 0, 0 };
100 static const char in_loopback[] = { 127, 0, 0, 1 };
101 #ifdef INET6
102 static const char in6_addrany[] = {
103 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
104 };
105 static const char in6_loopback[] = {
106 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
107 };
108 #endif
109
110 struct policyqueue {
111 TAILQ_ENTRY(policyqueue) pc_entry;
112 #ifdef INET6
113 struct in6_addrpolicy pc_policy;
114 #endif
115 };
116 TAILQ_HEAD(policyhead, policyqueue);
117
118 static const struct afd {
119 int a_af;
120 int a_addrlen;
121 socklen_t a_socklen;
122 int a_off;
123 const char *a_addrany;
124 const char *a_loopback;
125 int a_scoped;
126 } afdl [] = {
127 #ifdef INET6
128 #define N_INET6 0
129 {PF_INET6, sizeof(struct in6_addr),
130 sizeof(struct sockaddr_in6),
131 offsetof(struct sockaddr_in6, sin6_addr),
132 in6_addrany, in6_loopback, 1},
133 #define N_INET 1
134 #else
135 #define N_INET 0
136 #endif
137 {PF_INET, sizeof(struct in_addr),
138 sizeof(struct sockaddr_in),
139 offsetof(struct sockaddr_in, sin_addr),
140 in_addrany, in_loopback, 0},
141 {0, 0, 0, 0, NULL, NULL, 0},
142 };
143
144 struct explore {
145 int e_af;
146 int e_socktype;
147 int e_protocol;
148 const char *e_protostr;
149 int e_wild;
150 #define WILD_AF(ex) ((ex)->e_wild & 0x01)
151 #define WILD_SOCKTYPE(ex) ((ex)->e_wild & 0x02)
152 #define WILD_PROTOCOL(ex) ((ex)->e_wild & 0x04)
153 };
154
155 static const struct explore explore[] = {
156 #if 0
157 { PF_LOCAL, 0, ANY, ANY, NULL, 0x01 },
158 #endif
159 #ifdef INET6
160 { PF_INET6, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
161 { PF_INET6, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
162 { PF_INET6, SOCK_RAW, ANY, NULL, 0x05 },
163 #endif
164 { PF_INET, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
165 { PF_INET, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
166 { PF_INET, SOCK_RAW, ANY, NULL, 0x05 },
167 { PF_UNSPEC, SOCK_DGRAM, IPPROTO_UDP, "udp", 0x07 },
168 { PF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, "tcp", 0x07 },
169 { PF_UNSPEC, SOCK_RAW, ANY, NULL, 0x05 },
170 { -1, 0, 0, NULL, 0 },
171 };
172
173 #ifdef INET6
174 #define PTON_MAX 16
175 #else
176 #define PTON_MAX 4
177 #endif
178
179 #define AIO_SRCFLAG_DEPRECATED 0x1
180
181 struct ai_order {
182 union {
183 struct sockaddr_storage aiou_ss;
184 struct sockaddr aiou_sa;
185 } aio_src_un;
186 #define aio_srcsa aio_src_un.aiou_sa
187 u_int32_t aio_srcflag;
188 int aio_srcscope;
189 int aio_dstscope;
190 struct policyqueue *aio_srcpolicy;
191 struct policyqueue *aio_dstpolicy;
192 struct addrinfo *aio_ai;
193 int aio_matchlen;
194 };
195
196 static const ns_src default_dns_files[] = {
197 { NSSRC_FILES, NS_SUCCESS },
198 { NSSRC_DNS, NS_SUCCESS },
199 { 0 }
200 };
201
202 struct res_target {
203 struct res_target *next;
204 const char *name; /* domain name */
205 int qclass, qtype; /* class and type of query */
206 u_char *answer; /* buffer to put answer */
207 int anslen; /* size of answer buffer */
208 int n; /* result length */
209 };
210
211 #define MAXPACKET (64*1024)
212
213 typedef union {
214 HEADER hdr;
215 u_char buf[MAXPACKET];
216 } querybuf;
217
218 static int str2number(const char *, int *);
219 static int explore_null(const struct addrinfo *,
220 const char *, struct addrinfo **);
221 static int explore_numeric(const struct addrinfo *, const char *,
222 const char *, struct addrinfo **, const char *);
223 static int explore_numeric_scope(const struct addrinfo *, const char *,
224 const char *, struct addrinfo **);
225 static int get_canonname(const struct addrinfo *,
226 struct addrinfo *, const char *);
227 static struct addrinfo *get_ai(const struct addrinfo *,
228 const struct afd *, const char *);
229 static int get_portmatch(const struct addrinfo *, const char *);
230 static int get_port(struct addrinfo *, const char *, int);
231 static const struct afd *find_afd(int);
232 static int addrconfig(struct addrinfo *);
233 static void set_source(struct ai_order *, struct policyhead *);
234 static int comp_dst(const void *, const void *);
235 #ifdef INET6
236 static int ip6_str2scopeid(char *, struct sockaddr_in6 *, u_int32_t *);
237 #endif
238 static int gai_addr2scopetype(struct sockaddr *);
239
240 static int explore_fqdn(const struct addrinfo *, const char *,
241 const char *, struct addrinfo **);
242
243 static int reorder(struct addrinfo *);
244 static int get_addrselectpolicy(struct policyhead *);
245 static void free_addrselectpolicy(struct policyhead *);
246 static struct policyqueue *match_addrselectpolicy(struct sockaddr *,
247 struct policyhead *);
248 static int matchlen(struct sockaddr *, struct sockaddr *);
249
250 static struct addrinfo *getanswer(const querybuf *, int, const char *, int,
251 const struct addrinfo *, res_state);
252 #if defined(RESOLVSORT)
253 static int addr4sort(struct addrinfo *, res_state);
254 #endif
255 static int _dns_getaddrinfo(void *, void *, va_list);
256 static void _sethtent(FILE **);
257 static void _endhtent(FILE **);
258 static struct addrinfo *_gethtent(FILE **, const char *,
259 const struct addrinfo *);
260 static int _files_getaddrinfo(void *, void *, va_list);
261 #ifdef YP
262 static struct addrinfo *_yphostent(char *, const struct addrinfo *);
263 static int _yp_getaddrinfo(void *, void *, va_list);
264 #endif
265 #ifdef NS_CACHING
266 static int addrinfo_id_func(char *, size_t *, va_list, void *);
267 static int addrinfo_marshal_func(char *, size_t *, void *, va_list,
268 void *);
269 static int addrinfo_unmarshal_func(char *, size_t, void *, va_list,
270 void *);
271 #endif
272
273 static int res_queryN(const char *, struct res_target *, res_state);
274 static int res_searchN(const char *, struct res_target *, res_state);
275 static int res_querydomainN(const char *, const char *,
276 struct res_target *, res_state);
277
278 /* XXX macros that make external reference is BAD. */
279
280 #define GET_AI(ai, afd, addr) \
281 do { \
282 /* external reference: pai, error, and label free */ \
283 (ai) = get_ai(pai, (afd), (addr)); \
284 if ((ai) == NULL) { \
285 error = EAI_MEMORY; \
286 goto free; \
287 } \
288 } while (/*CONSTCOND*/0)
289
290 #define GET_PORT(ai, serv) \
291 do { \
292 /* external reference: error and label free */ \
293 error = get_port((ai), (serv), 0); \
294 if (error != 0) \
295 goto free; \
296 } while (/*CONSTCOND*/0)
297
298 #define GET_CANONNAME(ai, str) \
299 do { \
300 /* external reference: pai, error and label free */ \
301 error = get_canonname(pai, (ai), (str)); \
302 if (error != 0) \
303 goto free; \
304 } while (/*CONSTCOND*/0)
305
306 #define ERR(err) \
307 do { \
308 /* external reference: error, and label bad */ \
309 error = (err); \
310 goto bad; \
311 /*NOTREACHED*/ \
312 } while (/*CONSTCOND*/0)
313
314 #define MATCH_FAMILY(x, y, w) \
315 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == PF_UNSPEC || (y) == PF_UNSPEC)))
316 #define MATCH(x, y, w) \
317 ((x) == (y) || (/*CONSTCOND*/(w) && ((x) == ANY || (y) == ANY)))
318
319 void
320 freeaddrinfo(struct addrinfo *ai)
321 {
322 struct addrinfo *next;
323
324 do {
325 next = ai->ai_next;
326 if (ai->ai_canonname)
327 free(ai->ai_canonname);
328 /* no need to free(ai->ai_addr) */
329 free(ai);
330 ai = next;
331 } while (ai);
332 }
333
334 static int
335 str2number(const char *p, int *portp)
336 {
337 char *ep;
338 unsigned long v;
339
340 if (*p == '\0')
341 return -1;
342 ep = NULL;
343 errno = 0;
344 v = strtoul(p, &ep, 10);
345 if (errno == 0 && ep && *ep == '\0' && v <= UINT_MAX) {
346 *portp = v;
347 return 0;
348 } else
349 return -1;
350 }
351
352 int
353 getaddrinfo(const char * __restrict hostname, const char * __restrict servname,
354 const struct addrinfo * __restrict hints, struct addrinfo ** __restrict res)
355 {
356 struct addrinfo sentinel;
357 struct addrinfo *cur;
358 int error = 0;
359 struct addrinfo ai;
360 struct addrinfo ai0;
361 struct addrinfo *pai;
362 const struct explore *ex;
363 int numeric = 0;
364
365 memset(&sentinel, 0, sizeof(sentinel));
366 cur = &sentinel;
367 pai = &ai;
368 pai->ai_flags = 0;
369 pai->ai_family = PF_UNSPEC;
370 pai->ai_socktype = ANY;
371 pai->ai_protocol = ANY;
372 pai->ai_addrlen = 0;
373 pai->ai_canonname = NULL;
374 pai->ai_addr = NULL;
375 pai->ai_next = NULL;
376
377 if (hostname == NULL && servname == NULL)
378 return EAI_NONAME;
379 if (hints) {
380 /* error check for hints */
381 if (hints->ai_addrlen || hints->ai_canonname ||
382 hints->ai_addr || hints->ai_next)
383 ERR(EAI_BADHINTS); /* xxx */
384 if (hints->ai_flags & ~AI_MASK)
385 ERR(EAI_BADFLAGS);
386 switch (hints->ai_family) {
387 case PF_UNSPEC:
388 case PF_INET:
389 #ifdef INET6
390 case PF_INET6:
391 #endif
392 break;
393 default:
394 ERR(EAI_FAMILY);
395 }
396 memcpy(pai, hints, sizeof(*pai));
397
398 /*
399 * if both socktype/protocol are specified, check if they
400 * are meaningful combination.
401 */
402 if (pai->ai_socktype != ANY && pai->ai_protocol != ANY) {
403 for (ex = explore; ex->e_af >= 0; ex++) {
404 if (pai->ai_family != ex->e_af)
405 continue;
406 if (ex->e_socktype == ANY)
407 continue;
408 if (ex->e_protocol == ANY)
409 continue;
410 if (pai->ai_socktype == ex->e_socktype &&
411 pai->ai_protocol != ex->e_protocol) {
412 ERR(EAI_BADHINTS);
413 }
414 }
415 }
416 }
417
418 /*
419 * check for special cases. (1) numeric servname is disallowed if
420 * socktype/protocol are left unspecified. (2) servname is disallowed
421 * for raw and other inet{,6} sockets.
422 */
423 if (MATCH_FAMILY(pai->ai_family, PF_INET, 1)
424 #ifdef PF_INET6
425 || MATCH_FAMILY(pai->ai_family, PF_INET6, 1)
426 #endif
427 ) {
428 ai0 = *pai; /* backup *pai */
429
430 if (pai->ai_family == PF_UNSPEC) {
431 #ifdef PF_INET6
432 pai->ai_family = PF_INET6;
433 #else
434 pai->ai_family = PF_INET;
435 #endif
436 }
437 error = get_portmatch(pai, servname);
438 if (error)
439 ERR(error);
440
441 *pai = ai0;
442 }
443
444 ai0 = *pai;
445
446 /* NULL hostname, or numeric hostname */
447 for (ex = explore; ex->e_af >= 0; ex++) {
448 *pai = ai0;
449
450 /* PF_UNSPEC entries are prepared for DNS queries only */
451 if (ex->e_af == PF_UNSPEC)
452 continue;
453
454 if (!MATCH_FAMILY(pai->ai_family, ex->e_af, WILD_AF(ex)))
455 continue;
456 if (!MATCH(pai->ai_socktype, ex->e_socktype, WILD_SOCKTYPE(ex)))
457 continue;
458 if (!MATCH(pai->ai_protocol, ex->e_protocol, WILD_PROTOCOL(ex)))
459 continue;
460
461 if (pai->ai_family == PF_UNSPEC)
462 pai->ai_family = ex->e_af;
463 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
464 pai->ai_socktype = ex->e_socktype;
465 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
466 pai->ai_protocol = ex->e_protocol;
467
468 if (hostname == NULL)
469 error = explore_null(pai, servname, &cur->ai_next);
470 else
471 error = explore_numeric_scope(pai, hostname, servname,
472 &cur->ai_next);
473
474 if (error)
475 goto free;
476
477 while (cur && cur->ai_next)
478 cur = cur->ai_next;
479 }
480
481 /*
482 * XXX
483 * If numreic representation of AF1 can be interpreted as FQDN
484 * representation of AF2, we need to think again about the code below.
485 */
486 if (sentinel.ai_next) {
487 numeric = 1;
488 goto good;
489 }
490
491 if (hostname == NULL)
492 ERR(EAI_NONAME); /* used to be EAI_NODATA */
493 if (pai->ai_flags & AI_NUMERICHOST)
494 ERR(EAI_NONAME);
495
496 if ((pai->ai_flags & AI_ADDRCONFIG) != 0 && !addrconfig(&ai0))
497 ERR(EAI_FAIL);
498
499 /*
500 * hostname as alphabetical name.
501 * we would like to prefer AF_INET6 than AF_INET, so we'll make a
502 * outer loop by AFs.
503 */
504 for (ex = explore; ex->e_af >= 0; ex++) {
505 *pai = ai0;
506
507 /* require exact match for family field */
508 if (pai->ai_family != ex->e_af)
509 continue;
510
511 if (!MATCH(pai->ai_socktype, ex->e_socktype,
512 WILD_SOCKTYPE(ex))) {
513 continue;
514 }
515 if (!MATCH(pai->ai_protocol, ex->e_protocol,
516 WILD_PROTOCOL(ex))) {
517 continue;
518 }
519
520 if (pai->ai_socktype == ANY && ex->e_socktype != ANY)
521 pai->ai_socktype = ex->e_socktype;
522 if (pai->ai_protocol == ANY && ex->e_protocol != ANY)
523 pai->ai_protocol = ex->e_protocol;
524
525 error = explore_fqdn(pai, hostname, servname, &cur->ai_next);
526
527 while (cur && cur->ai_next)
528 cur = cur->ai_next;
529 }
530
531 /* XXX inhibit errors if we have the result */
532 if (sentinel.ai_next)
533 error = 0;
534
535 good:
536 /*
537 * ensure we return either:
538 * - error == 0, non-NULL *res
539 * - error != 0, NULL *res
540 */
541 if (error == 0) {
542 if (sentinel.ai_next) {
543 /*
544 * If the returned entry is for an active connection,
545 * and the given name is not numeric, reorder the
546 * list, so that the application would try the list
547 * in the most efficient order. Since the head entry
548 * of the original list may contain ai_canonname and
549 * that entry may be moved elsewhere in the new list,
550 * we keep the pointer and will restore it in the new
551 * head entry. (Note that RFC3493 requires the head
552 * entry store it when requested by the caller).
553 */
554 if (hints == NULL || !(hints->ai_flags & AI_PASSIVE)) {
555 if (!numeric) {
556 char *canonname;
557
558 canonname =
559 sentinel.ai_next->ai_canonname;
560 sentinel.ai_next->ai_canonname = NULL;
561 reorder(&sentinel);
562 if (sentinel.ai_next->ai_canonname ==
563 NULL) {
564 sentinel.ai_next->ai_canonname
565 = canonname;
566 } else if (canonname != NULL)
567 free(canonname);
568 }
569 }
570 *res = sentinel.ai_next;
571 return SUCCESS;
572 } else
573 error = EAI_FAIL;
574 }
575 free:
576 bad:
577 if (sentinel.ai_next)
578 freeaddrinfo(sentinel.ai_next);
579 *res = NULL;
580 return error;
581 }
582
583 static int
584 reorder(struct addrinfo *sentinel)
585 {
586 struct addrinfo *ai, **aip;
587 struct ai_order *aio;
588 int i, n;
589 struct policyhead policyhead;
590
591 /* count the number of addrinfo elements for sorting. */
592 for (n = 0, ai = sentinel->ai_next; ai != NULL; ai = ai->ai_next, n++)
593 ;
594
595 /*
596 * If the number is small enough, we can skip the reordering process.
597 */
598 if (n <= 1)
599 return(n);
600
601 /* allocate a temporary array for sort and initialization of it. */
602 if ((aio = malloc(sizeof(*aio) * n)) == NULL)
603 return(n); /* give up reordering */
604 memset(aio, 0, sizeof(*aio) * n);
605
606 /* retrieve address selection policy from the kernel */
607 TAILQ_INIT(&policyhead);
608 if (!get_addrselectpolicy(&policyhead)) {
609 /* no policy is installed into kernel, we don't sort. */
610 free(aio);
611 return (n);
612 }
613
614 for (i = 0, ai = sentinel->ai_next; i < n; ai = ai->ai_next, i++) {
615 aio[i].aio_ai = ai;
616 aio[i].aio_dstscope = gai_addr2scopetype(ai->ai_addr);
617 aio[i].aio_dstpolicy = match_addrselectpolicy(ai->ai_addr,
618 &policyhead);
619 set_source(&aio[i], &policyhead);
620 }
621
622 /* perform sorting. */
623 qsort(aio, n, sizeof(*aio), comp_dst);
624
625 /* reorder the addrinfo chain. */
626 for (i = 0, aip = &sentinel->ai_next; i < n; i++) {
627 *aip = aio[i].aio_ai;
628 aip = &aio[i].aio_ai->ai_next;
629 }
630 *aip = NULL;
631
632 /* cleanup and return */
633 free(aio);
634 free_addrselectpolicy(&policyhead);
635 return(n);
636 }
637
638 static int
639 get_addrselectpolicy(struct policyhead *head)
640 {
641 #ifdef INET6
642 int mib[] = { CTL_NET, PF_INET6, IPPROTO_IPV6, IPV6CTL_ADDRCTLPOLICY };
643 size_t l;
644 char *buf;
645 struct in6_addrpolicy *pol, *ep;
646
647 if (sysctl(mib, NELEM(mib), NULL, &l, NULL, 0) < 0)
648 return (0);
649 if ((buf = malloc(l)) == NULL)
650 return (0);
651 if (sysctl(mib, NELEM(mib), buf, &l, NULL, 0) < 0) {
652 free(buf);
653 return (0);
654 }
655
656 ep = (struct in6_addrpolicy *)(buf + l);
657 for (pol = (struct in6_addrpolicy *)buf; pol + 1 <= ep; pol++) {
658 struct policyqueue *new;
659
660 if ((new = malloc(sizeof(*new))) == NULL) {
661 free_addrselectpolicy(head); /* make the list empty */
662 break;
663 }
664 new->pc_policy = *pol;
665 TAILQ_INSERT_TAIL(head, new, pc_entry);
666 }
667
668 free(buf);
669 return (1);
670 #else
671 return (0);
672 #endif
673 }
674
675 static void
676 free_addrselectpolicy(struct policyhead *head)
677 {
678 struct policyqueue *ent, *nent;
679
680 for (ent = TAILQ_FIRST(head); ent; ent = nent) {
681 nent = TAILQ_NEXT(ent, pc_entry);
682 TAILQ_REMOVE(head, ent, pc_entry);
683 free(ent);
684 }
685 }
686
687 static struct policyqueue *
688 match_addrselectpolicy(struct sockaddr *addr, struct policyhead *head)
689 {
690 #ifdef INET6
691 struct policyqueue *ent, *bestent = NULL;
692 struct in6_addrpolicy *pol;
693 int matchlen, bestmatchlen = -1;
694 u_char *mp, *ep, *k, *p, m;
695 struct sockaddr_in6 key;
696
697 switch(addr->sa_family) {
698 case AF_INET6:
699 key = *(struct sockaddr_in6 *)addr;
700 break;
701 case AF_INET:
702 /* convert the address into IPv4-mapped IPv6 address. */
703 memset(&key, 0, sizeof(key));
704 key.sin6_family = AF_INET6;
705 key.sin6_len = sizeof(key);
706 key.sin6_addr.s6_addr[10] = 0xff;
707 key.sin6_addr.s6_addr[11] = 0xff;
708 memcpy(&key.sin6_addr.s6_addr[12],
709 &((struct sockaddr_in *)addr)->sin_addr, 4);
710 break;
711 default:
712 return(NULL);
713 }
714
715 for (ent = TAILQ_FIRST(head); ent; ent = TAILQ_NEXT(ent, pc_entry)) {
716 pol = &ent->pc_policy;
717 matchlen = 0;
718
719 mp = (u_char *)&pol->addrmask.sin6_addr;
720 ep = mp + 16; /* XXX: scope field? */
721 k = (u_char *)&key.sin6_addr;
722 p = (u_char *)&pol->addr.sin6_addr;
723 for (; mp < ep && *mp; mp++, k++, p++) {
724 m = *mp;
725 if ((*k & m) != *p)
726 goto next; /* not match */
727 if (m == 0xff) /* short cut for a typical case */
728 matchlen += 8;
729 else {
730 while (m >= 0x80) {
731 matchlen++;
732 m <<= 1;
733 }
734 }
735 }
736
737 /* matched. check if this is better than the current best. */
738 if (matchlen > bestmatchlen) {
739 bestent = ent;
740 bestmatchlen = matchlen;
741 }
742
743 next:
744 continue;
745 }
746
747 return(bestent);
748 #else
749 return(NULL);
750 #endif
751
752 }
753
754 static void
755 set_source(struct ai_order *aio, struct policyhead *ph)
756 {
757 struct addrinfo ai = *aio->aio_ai;
758 struct sockaddr_storage ss;
759 socklen_t srclen;
760 int s;
761
762 /* set unspec ("no source is available"), just in case */
763 aio->aio_srcsa.sa_family = AF_UNSPEC;
764 aio->aio_srcscope = -1;
765
766 switch(ai.ai_family) {
767 case AF_INET:
768 #ifdef INET6
769 case AF_INET6:
770 #endif
771 break;
772 default: /* ignore unsupported AFs explicitly */
773 return;
774 }
775
776 /* XXX: make a dummy addrinfo to call connect() */
777 ai.ai_socktype = SOCK_DGRAM;
778 ai.ai_protocol = IPPROTO_UDP; /* is UDP too specific? */
779 ai.ai_next = NULL;
780 memset(&ss, 0, sizeof(ss));
781 memcpy(&ss, ai.ai_addr, ai.ai_addrlen);
782 ai.ai_addr = (struct sockaddr *)&ss;
783 get_port(&ai, "1", 0);
784
785 /* open a socket to get the source address for the given dst */
786 if ((s = _socket(ai.ai_family, ai.ai_socktype, ai.ai_protocol)) < 0)
787 return; /* give up */
788 if (_connect(s, ai.ai_addr, ai.ai_addrlen) < 0)
789 goto cleanup;
790 srclen = ai.ai_addrlen;
791 if (_getsockname(s, &aio->aio_srcsa, &srclen) < 0) {
792 aio->aio_srcsa.sa_family = AF_UNSPEC;
793 goto cleanup;
794 }
795 aio->aio_srcscope = gai_addr2scopetype(&aio->aio_srcsa);
796 aio->aio_srcpolicy = match_addrselectpolicy(&aio->aio_srcsa, ph);
797 aio->aio_matchlen = matchlen(&aio->aio_srcsa, aio->aio_ai->ai_addr);
798 #ifdef INET6
799 if (ai.ai_family == AF_INET6) {
800 struct in6_ifreq ifr6;
801 u_int32_t flags6;
802
803 /* XXX: interface name should not be hardcoded */
804 strncpy(ifr6.ifr_name, "lo0", sizeof(ifr6.ifr_name));
805 memset(&ifr6, 0, sizeof(ifr6));
806 memcpy(&ifr6.ifr_addr, ai.ai_addr, ai.ai_addrlen);
807 if (_ioctl(s, SIOCGIFAFLAG_IN6, &ifr6) == 0) {
808 flags6 = ifr6.ifr_ifru.ifru_flags6;
809 if ((flags6 & IN6_IFF_DEPRECATED))
810 aio->aio_srcflag |= AIO_SRCFLAG_DEPRECATED;
811 }
812 }
813 #endif
814
815 cleanup:
816 _close(s);
817 return;
818 }
819
820 static int
821 matchlen(struct sockaddr *src, struct sockaddr *dst)
822 {
823 int match = 0;
824 u_char *s, *d;
825 u_char *lim, r;
826 int addrlen;
827
828 switch (src->sa_family) {
829 #ifdef INET6
830 case AF_INET6:
831 s = (u_char *)&((struct sockaddr_in6 *)src)->sin6_addr;
832 d = (u_char *)&((struct sockaddr_in6 *)dst)->sin6_addr;
833 addrlen = sizeof(struct in6_addr);
834 lim = s + addrlen;
835 break;
836 #endif
837 case AF_INET:
838 s = (u_char *)&((struct sockaddr_in *)src)->sin_addr;
839 d = (u_char *)&((struct sockaddr_in *)dst)->sin_addr;
840 addrlen = sizeof(struct in_addr);
841 lim = s + addrlen;
842 break;
843 default:
844 return(0);
845 }
846
847 while (s < lim)
848 if ((r = (*d++ ^ *s++)) != 0) {
849 while (r < addrlen * 8) {
850 match++;
851 r <<= 1;
852 }
853 break;
854 } else
855 match += 8;
856 return(match);
857 }
858
859 static int
860 comp_dst(const void *arg1, const void *arg2)
861 {
862 const struct ai_order *dst1 = arg1, *dst2 = arg2;
863
864 /*
865 * Rule 1: Avoid unusable destinations.
866 * XXX: we currently do not consider if an appropriate route exists.
867 */
868 if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
869 dst2->aio_srcsa.sa_family == AF_UNSPEC) {
870 return(-1);
871 }
872 if (dst1->aio_srcsa.sa_family == AF_UNSPEC &&
873 dst2->aio_srcsa.sa_family != AF_UNSPEC) {
874 return(1);
875 }
876
877 /* Rule 2: Prefer matching scope. */
878 if (dst1->aio_dstscope == dst1->aio_srcscope &&
879 dst2->aio_dstscope != dst2->aio_srcscope) {
880 return(-1);
881 }
882 if (dst1->aio_dstscope != dst1->aio_srcscope &&
883 dst2->aio_dstscope == dst2->aio_srcscope) {
884 return(1);
885 }
886
887 /* Rule 3: Avoid deprecated addresses. */
888 if (dst1->aio_srcsa.sa_family != AF_UNSPEC &&
889 dst2->aio_srcsa.sa_family != AF_UNSPEC) {
890 if (!(dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
891 (dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
892 return(-1);
893 }
894 if ((dst1->aio_srcflag & AIO_SRCFLAG_DEPRECATED) &&
895 !(dst2->aio_srcflag & AIO_SRCFLAG_DEPRECATED)) {
896 return(1);
897 }
898 }
899
900 /* Rule 4: Prefer home addresses. */
901 /* XXX: not implemented yet */
902
903 /* Rule 5: Prefer matching label. */
904 #ifdef INET6
905 if (dst1->aio_srcpolicy && dst1->aio_dstpolicy &&
906 dst1->aio_srcpolicy->pc_policy.label ==
907 dst1->aio_dstpolicy->pc_policy.label &&
908 (dst2->aio_srcpolicy == NULL || dst2->aio_dstpolicy == NULL ||
909 dst2->aio_srcpolicy->pc_policy.label !=
910 dst2->aio_dstpolicy->pc_policy.label)) {
911 return(-1);
912 }
913 if (dst2->aio_srcpolicy && dst2->aio_dstpolicy &&
914 dst2->aio_srcpolicy->pc_policy.label ==
915 dst2->aio_dstpolicy->pc_policy.label &&
916 (dst1->aio_srcpolicy == NULL || dst1->aio_dstpolicy == NULL ||
917 dst1->aio_srcpolicy->pc_policy.label !=
918 dst1->aio_dstpolicy->pc_policy.label)) {
919 return(1);
920 }
921 #endif
922
923 /* Rule 6: Prefer higher precedence. */
924 #ifdef INET6
925 if (dst1->aio_dstpolicy &&
926 (dst2->aio_dstpolicy == NULL ||
927 dst1->aio_dstpolicy->pc_policy.preced >
928 dst2->aio_dstpolicy->pc_policy.preced)) {
929 return(-1);
930 }
931 if (dst2->aio_dstpolicy &&
932 (dst1->aio_dstpolicy == NULL ||
933 dst2->aio_dstpolicy->pc_policy.preced >
934 dst1->aio_dstpolicy->pc_policy.preced)) {
935 return(1);
936 }
937 #endif
938
939 /* Rule 7: Prefer native transport. */
940 /* XXX: not implemented yet */
941
942 /* Rule 8: Prefer smaller scope. */
943 if (dst1->aio_dstscope >= 0 &&
944 dst1->aio_dstscope < dst2->aio_dstscope) {
945 return(-1);
946 }
947 if (dst2->aio_dstscope >= 0 &&
948 dst2->aio_dstscope < dst1->aio_dstscope) {
949 return(1);
950 }
951
952 /*
953 * Rule 9: Use longest matching prefix.
954 * We compare the match length in a same AF only.
955 */
956 if (dst1->aio_ai->ai_addr->sa_family ==
957 dst2->aio_ai->ai_addr->sa_family) {
958 if (dst1->aio_matchlen > dst2->aio_matchlen) {
959 return(-1);
960 }
961 if (dst1->aio_matchlen < dst2->aio_matchlen) {
962 return(1);
963 }
964 }
965
966 /* Rule 10: Otherwise, leave the order unchanged. */
967 return(-1);
968 }
969
970 /*
971 * Copy from scope.c.
972 * XXX: we should standardize the functions and link them as standard
973 * library.
974 */
975 static int
976 gai_addr2scopetype(struct sockaddr *sa)
977 {
978 #ifdef INET6
979 struct sockaddr_in6 *sa6;
980 #endif
981 struct sockaddr_in *sa4;
982
983 switch(sa->sa_family) {
984 #ifdef INET6
985 case AF_INET6:
986 sa6 = (struct sockaddr_in6 *)sa;
987 if (IN6_IS_ADDR_MULTICAST(&sa6->sin6_addr)) {
988 /* just use the scope field of the multicast address */
989 return(sa6->sin6_addr.s6_addr[2] & 0x0f);
990 }
991 /*
992 * Unicast addresses: map scope type to corresponding scope
993 * value defined for multcast addresses.
994 * XXX: hardcoded scope type values are bad...
995 */
996 if (IN6_IS_ADDR_LOOPBACK(&sa6->sin6_addr))
997 return(1); /* node local scope */
998 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr))
999 return(2); /* link-local scope */
1000 if (IN6_IS_ADDR_SITELOCAL(&sa6->sin6_addr))
1001 return(5); /* site-local scope */
1002 return(14); /* global scope */
1003 break;
1004 #endif
1005 case AF_INET:
1006 /*
1007 * IPv4 pseudo scoping according to RFC 3484.
1008 */
1009 sa4 = (struct sockaddr_in *)sa;
1010 /* IPv4 autoconfiguration addresses have link-local scope. */
1011 if (((u_char *)&sa4->sin_addr)[0] == 169 &&
1012 ((u_char *)&sa4->sin_addr)[1] == 254)
1013 return(2);
1014 /* Private addresses have site-local scope. */
1015 if (((u_char *)&sa4->sin_addr)[0] == 10 ||
1016 (((u_char *)&sa4->sin_addr)[0] == 172 &&
1017 (((u_char *)&sa4->sin_addr)[1] & 0xf0) == 16) ||
1018 (((u_char *)&sa4->sin_addr)[0] == 192 &&
1019 ((u_char *)&sa4->sin_addr)[1] == 168))
1020 return(14); /* XXX: It should be 5 unless NAT */
1021 /* Loopback addresses have link-local scope. */
1022 if (((u_char *)&sa4->sin_addr)[0] == 127)
1023 return(2);
1024 return(14);
1025 break;
1026 default:
1027 errno = EAFNOSUPPORT; /* is this a good error? */
1028 return(-1);
1029 }
1030 }
1031
1032 /*
1033 * hostname == NULL.
1034 * passive socket -> anyaddr (0.0.0.0 or ::)
1035 * non-passive socket -> localhost (127.0.0.1 or ::1)
1036 */
1037 static int
1038 explore_null(const struct addrinfo *pai, const char *servname,
1039 struct addrinfo **res)
1040 {
1041 int s;
1042 const struct afd *afd;
1043 struct addrinfo *ai;
1044 int error;
1045
1046 *res = NULL;
1047 ai = NULL;
1048
1049 /*
1050 * filter out AFs that are not supported by the kernel
1051 * XXX errno?
1052 */
1053 s = _socket(pai->ai_family, SOCK_DGRAM, 0);
1054 if (s < 0) {
1055 if (errno != EMFILE)
1056 return 0;
1057 } else
1058 _close(s);
1059
1060 /*
1061 * if the servname does not match socktype/protocol, ignore it.
1062 */
1063 if (get_portmatch(pai, servname) != 0)
1064 return 0;
1065
1066 afd = find_afd(pai->ai_family);
1067 if (afd == NULL)
1068 return 0;
1069
1070 if (pai->ai_flags & AI_PASSIVE) {
1071 GET_AI(ai, afd, afd->a_addrany);
1072 GET_PORT(ai, servname);
1073 } else {
1074 GET_AI(ai, afd, afd->a_loopback);
1075 GET_PORT(ai, servname);
1076 }
1077
1078 *res = ai;
1079 return 0;
1080
1081 free:
1082 if (ai != NULL)
1083 freeaddrinfo(ai);
1084 return error;
1085 }
1086
1087 /*
1088 * numeric hostname
1089 */
1090 static int
1091 explore_numeric(const struct addrinfo *pai, const char *hostname,
1092 const char *servname, struct addrinfo **res,
1093 const char *canonname)
1094 {
1095 const struct afd *afd;
1096 struct addrinfo *ai;
1097 int error;
1098 char pton[PTON_MAX];
1099
1100 *res = NULL;
1101 ai = NULL;
1102
1103 /*
1104 * if the servname does not match socktype/protocol, ignore it.
1105 */
1106 if (get_portmatch(pai, servname) != 0)
1107 return 0;
1108
1109 afd = find_afd(pai->ai_family);
1110 if (afd == NULL)
1111 return 0;
1112
1113 switch (afd->a_af) {
1114 case AF_INET:
1115 /*
1116 * RFC3493 requires getaddrinfo() to accept AF_INET formats
1117 * that are accepted by inet_addr() and its family. The
1118 * accepted forms includes the "classful" one, which inet_pton
1119 * does not accept. So we need to separate the case for
1120 * AF_INET.
1121 */
1122 if (inet_aton(hostname, (struct in_addr *)pton) != 1)
1123 return 0;
1124 break;
1125 default:
1126 if (inet_pton(afd->a_af, hostname, pton) != 1)
1127 return 0;
1128 break;
1129 }
1130
1131 if (pai->ai_family == afd->a_af) {
1132 GET_AI(ai, afd, pton);
1133 GET_PORT(ai, servname);
1134 if ((pai->ai_flags & AI_CANONNAME)) {
1135 /*
1136 * Set the numeric address itself as the canonical
1137 * name, based on a clarification in RFC3493.
1138 */
1139 GET_CANONNAME(ai, canonname);
1140 }
1141 } else {
1142 /*
1143 * XXX: This should not happen since we already matched the AF
1144 * by find_afd.
1145 */
1146 ERR(EAI_FAMILY);
1147 }
1148
1149 *res = ai;
1150 return 0;
1151
1152 free:
1153 bad:
1154 if (ai != NULL)
1155 freeaddrinfo(ai);
1156 return error;
1157 }
1158
1159 /*
1160 * numeric hostname with scope
1161 */
1162 static int
1163 explore_numeric_scope(const struct addrinfo *pai, const char *hostname,
1164 const char *servname, struct addrinfo **res)
1165 {
1166 #if !defined(SCOPE_DELIMITER) || !defined(INET6)
1167 return explore_numeric(pai, hostname, servname, res, hostname);
1168 #else
1169 const struct afd *afd;
1170 struct addrinfo *cur;
1171 int error;
1172 char *cp, *hostname2 = NULL, *scope, *addr;
1173 struct sockaddr_in6 *sin6;
1174
1175 /*
1176 * if the servname does not match socktype/protocol, ignore it.
1177 */
1178 if (get_portmatch(pai, servname) != 0)
1179 return 0;
1180
1181 afd = find_afd(pai->ai_family);
1182 if (afd == NULL)
1183 return 0;
1184
1185 if (!afd->a_scoped)
1186 return explore_numeric(pai, hostname, servname, res, hostname);
1187
1188 cp = strchr(hostname, SCOPE_DELIMITER);
1189 if (cp == NULL)
1190 return explore_numeric(pai, hostname, servname, res, hostname);
1191
1192 /*
1193 * Handle special case of <scoped_address><delimiter><scope id>
1194 */
1195 hostname2 = strdup(hostname);
1196 if (hostname2 == NULL)
1197 return EAI_MEMORY;
1198 /* terminate at the delimiter */
1199 hostname2[cp - hostname] = '\0';
1200 addr = hostname2;
1201 scope = cp + 1;
1202
1203 error = explore_numeric(pai, addr, servname, res, hostname);
1204 if (error == 0) {
1205 u_int32_t scopeid;
1206
1207 for (cur = *res; cur; cur = cur->ai_next) {
1208 if (cur->ai_family != AF_INET6)
1209 continue;
1210 sin6 = (struct sockaddr_in6 *)(void *)cur->ai_addr;
1211 if (ip6_str2scopeid(scope, sin6, &scopeid) == -1) {
1212 free(hostname2);
1213 return(EAI_NONAME); /* XXX: is return OK? */
1214 }
1215 sin6->sin6_scope_id = scopeid;
1216 }
1217 }
1218
1219 free(hostname2);
1220
1221 return error;
1222 #endif
1223 }
1224
1225 static int
1226 get_canonname(const struct addrinfo *pai, struct addrinfo *ai, const char *str)
1227 {
1228 if ((pai->ai_flags & AI_CANONNAME) != 0) {
1229 ai->ai_canonname = strdup(str);
1230 if (ai->ai_canonname == NULL)
1231 return EAI_MEMORY;
1232 }
1233 return 0;
1234 }
1235
1236 static struct addrinfo *
1237 get_ai(const struct addrinfo *pai, const struct afd *afd, const char *addr)
1238 {
1239 char *p;
1240 struct addrinfo *ai;
1241
1242 ai = (struct addrinfo *)malloc(sizeof(struct addrinfo)
1243 + (afd->a_socklen));
1244 if (ai == NULL)
1245 return NULL;
1246
1247 memcpy(ai, pai, sizeof(struct addrinfo));
1248 ai->ai_addr = (struct sockaddr *)(void *)(ai + 1);
1249 memset(ai->ai_addr, 0, (size_t)afd->a_socklen);
1250 ai->ai_addr->sa_len = afd->a_socklen;
1251 ai->ai_addrlen = afd->a_socklen;
1252 ai->ai_addr->sa_family = ai->ai_family = afd->a_af;
1253 p = (char *)(void *)(ai->ai_addr);
1254 memcpy(p + afd->a_off, addr, (size_t)afd->a_addrlen);
1255 return ai;
1256 }
1257
1258 static int
1259 get_portmatch(const struct addrinfo *ai, const char *servname)
1260 {
1261
1262 /* get_port does not touch first argument when matchonly == 1. */
1263 /* LINTED const cast */
1264 return get_port((struct addrinfo *)ai, servname, 1);
1265 }
1266
1267 static int
1268 get_port(struct addrinfo *ai, const char *servname, int matchonly)
1269 {
1270 const char *proto;
1271 struct servent *sp;
1272 int port, error;
1273 int allownumeric;
1274
1275 if (servname == NULL)
1276 return 0;
1277 switch (ai->ai_family) {
1278 case AF_INET:
1279 #ifdef AF_INET6
1280 case AF_INET6:
1281 #endif
1282 break;
1283 default:
1284 return 0;
1285 }
1286
1287 switch (ai->ai_socktype) {
1288 case SOCK_RAW:
1289 return EAI_SERVICE;
1290 case SOCK_DGRAM:
1291 case SOCK_STREAM:
1292 allownumeric = 1;
1293 break;
1294 case ANY:
1295 allownumeric = 0;
1296 break;
1297 default:
1298 return EAI_SOCKTYPE;
1299 }
1300
1301 error = str2number(servname, &port);
1302 if (error == 0) {
1303 if (!allownumeric)
1304 return EAI_SERVICE;
1305 if (port < 0 || port > 65535)
1306 return EAI_SERVICE;
1307 port = htons(port);
1308 } else {
1309 if (ai->ai_flags & AI_NUMERICSERV)
1310 return EAI_NONAME;
1311 switch (ai->ai_socktype) {
1312 case SOCK_DGRAM:
1313 proto = "udp";
1314 break;
1315 case SOCK_STREAM:
1316 proto = "tcp";
1317 break;
1318 default:
1319 proto = NULL;
1320 break;
1321 }
1322
1323 if ((sp = getservbyname(servname, proto)) == NULL)
1324 return EAI_SERVICE;
1325 port = sp->s_port;
1326 }
1327
1328 if (!matchonly) {
1329 switch (ai->ai_family) {
1330 case AF_INET:
1331 ((struct sockaddr_in *)(void *)
1332 ai->ai_addr)->sin_port = port;
1333 break;
1334 #ifdef INET6
1335 case AF_INET6:
1336 ((struct sockaddr_in6 *)(void *)
1337 ai->ai_addr)->sin6_port = port;
1338 break;
1339 #endif
1340 }
1341 }
1342
1343 return 0;
1344 }
1345
1346 static const struct afd *
1347 find_afd(int af)
1348 {
1349 const struct afd *afd;
1350
1351 if (af == PF_UNSPEC)
1352 return NULL;
1353 for (afd = afdl; afd->a_af; afd++) {
1354 if (afd->a_af == af)
1355 return afd;
1356 }
1357 return NULL;
1358 }
1359
1360 /*
1361 * post-2553: AI_ADDRCONFIG check. if we use getipnodeby* as backend, backend
1362 * will take care of it.
1363 * the semantics of AI_ADDRCONFIG is not defined well. we are not sure
1364 * if the code is right or not.
1365 *
1366 * XXX PF_UNSPEC -> PF_INET6 + PF_INET mapping needs to be in sync with
1367 * _dns_getaddrinfo.
1368 */
1369 static int
1370 addrconfig(struct addrinfo *pai)
1371 {
1372 int s, af;
1373
1374 /*
1375 * TODO:
1376 * Note that implementation dependent test for address
1377 * configuration should be done everytime called
1378 * (or apropriate interval),
1379 * because addresses will be dynamically assigned or deleted.
1380 */
1381 af = pai->ai_family;
1382 if (af == AF_UNSPEC) {
1383 if ((s = _socket(AF_INET6, SOCK_DGRAM, 0)) < 0)
1384 af = AF_INET;
1385 else {
1386 _close(s);
1387 if ((s = _socket(AF_INET, SOCK_DGRAM, 0)) < 0)
1388 af = AF_INET6;
1389 else
1390 _close(s);
1391 }
1392 }
1393 if (af != AF_UNSPEC) {
1394 if ((s = _socket(af, SOCK_DGRAM, 0)) < 0)
1395 return 0;
1396 _close(s);
1397 }
1398 pai->ai_family = af;
1399 return 1;
1400 }
1401
1402 #ifdef INET6
1403 /* convert a string to a scope identifier. XXX: IPv6 specific */
1404 static int
1405 ip6_str2scopeid(char *scope, struct sockaddr_in6 *sin6, u_int32_t *scopeid)
1406 {
1407 u_long lscopeid;
1408 struct in6_addr *a6;
1409 char *ep;
1410
1411 a6 = &sin6->sin6_addr;
1412
1413 /* empty scopeid portion is invalid */
1414 if (*scope == '\0')
1415 return -1;
1416
1417 if (IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) {
1418 /*
1419 * We currently assume a one-to-one mapping between links
1420 * and interfaces, so we simply use interface indices for
1421 * like-local scopes.
1422 */
1423 *scopeid = if_nametoindex(scope);
1424 if (*scopeid == 0)
1425 goto trynumeric;
1426 return 0;
1427 }
1428
1429 /* still unclear about literal, allow numeric only - placeholder */
1430 if (IN6_IS_ADDR_SITELOCAL(a6) || IN6_IS_ADDR_MC_SITELOCAL(a6))
1431 goto trynumeric;
1432 if (IN6_IS_ADDR_MC_ORGLOCAL(a6))
1433 goto trynumeric;
1434 else
1435 goto trynumeric; /* global */
1436
1437 /* try to convert to a numeric id as a last resort */
1438 trynumeric:
1439 errno = 0;
1440 lscopeid = strtoul(scope, &ep, 10);
1441 *scopeid = (u_int32_t)(lscopeid & 0xffffffffUL);
1442 if (errno == 0 && ep && *ep == '\0' && *scopeid == lscopeid)
1443 return 0;
1444 else
1445 return -1;
1446 }
1447 #endif
1448
1449
1450 #ifdef NS_CACHING
1451 static int
1452 addrinfo_id_func(char *buffer, size_t *buffer_size, va_list ap,
1453 void *cache_mdata __unused)
1454 {
1455 res_state statp;
1456 u_long res_options;
1457
1458 const int op_id = 0; /* identifies the getaddrinfo for the cache */
1459 char *hostname;
1460 struct addrinfo *hints;
1461
1462 char *p;
1463 int ai_flags, ai_family, ai_socktype, ai_protocol;
1464 size_t desired_size, size;
1465
1466 statp = __res_state();
1467 res_options = statp->options & (RES_RECURSE | RES_DEFNAMES |
1468 RES_DNSRCH | RES_NOALIASES | RES_USE_INET6);
1469
1470 hostname = va_arg(ap, char *);
1471 hints = va_arg(ap, struct addrinfo *);
1472
1473 desired_size = sizeof(res_options) + sizeof(int) + sizeof(int) * 4;
1474 if (hostname != NULL) {
1475 size = strlen(hostname);
1476 desired_size += size + 1;
1477 } else
1478 size = 0;
1479
1480 if (desired_size > *buffer_size) {
1481 *buffer_size = desired_size;
1482 return (NS_RETURN);
1483 }
1484
1485 if (hints == NULL)
1486 ai_flags = ai_family = ai_socktype = ai_protocol = 0;
1487 else {
1488 ai_flags = hints->ai_flags;
1489 ai_family = hints->ai_family;
1490 ai_socktype = hints->ai_socktype;
1491 ai_protocol = hints->ai_protocol;
1492 }
1493
1494 p = buffer;
1495 memcpy(p, &res_options, sizeof(res_options));
1496 p += sizeof(res_options);
1497
1498 memcpy(p, &op_id, sizeof(int));
1499 p += sizeof(int);
1500
1501 memcpy(p, &ai_flags, sizeof(int));
1502 p += sizeof(int);
1503
1504 memcpy(p, &ai_family, sizeof(int));
1505 p += sizeof(int);
1506
1507 memcpy(p, &ai_socktype, sizeof(int));
1508 p += sizeof(int);
1509
1510 memcpy(p, &ai_protocol, sizeof(int));
1511 p += sizeof(int);
1512
1513 if (hostname != NULL)
1514 memcpy(p, hostname, size);
1515
1516 *buffer_size = desired_size;
1517 return (NS_SUCCESS);
1518 }
1519
1520 static int
1521 addrinfo_marshal_func(char *buffer, size_t *buffer_size, void *retval,
1522 va_list ap __unused, void *cache_mdata __unused)
1523 {
1524 struct addrinfo *ai, *cai;
1525 char *p;
1526 size_t desired_size, size, ai_size;
1527
1528 ai = *((struct addrinfo **)retval);
1529
1530 desired_size = sizeof(size_t);
1531 ai_size = 0;
1532 for (cai = ai; cai != NULL; cai = cai->ai_next) {
1533 desired_size += sizeof(struct addrinfo) + cai->ai_addrlen;
1534 if (cai->ai_canonname != NULL)
1535 desired_size += sizeof(size_t) +
1536 strlen(cai->ai_canonname);
1537 ++ai_size;
1538 }
1539
1540 if (desired_size > *buffer_size) {
1541 /* this assignment is here for future use */
1542 errno = ERANGE;
1543 *buffer_size = desired_size;
1544 return (NS_RETURN);
1545 }
1546
1547 memset(buffer, 0, desired_size);
1548 p = buffer;
1549
1550 memcpy(p, &ai_size, sizeof(size_t));
1551 p += sizeof(size_t);
1552 for (cai = ai; cai != NULL; cai = cai->ai_next) {
1553 memcpy(p, cai, sizeof(struct addrinfo));
1554 p += sizeof(struct addrinfo);
1555
1556 memcpy(p, cai->ai_addr, cai->ai_addrlen);
1557 p += cai->ai_addrlen;
1558
1559 if (cai->ai_canonname != NULL) {
1560 size = strlen(cai->ai_canonname);
1561 memcpy(p, &size, sizeof(size_t));
1562 p += sizeof(size_t);
1563
1564 memcpy(p, cai->ai_canonname, size);
1565 p += size;
1566 }
1567 }
1568
1569 return (NS_SUCCESS);
1570 }
1571
1572 static int
1573 addrinfo_unmarshal_func(char *buffer, size_t buffer_size __unused, void *retval,
1574 va_list ap __unused, void *cache_mdata __unused)
1575 {
1576 struct addrinfo new_ai, *result, *sentinel, *lasts;
1577
1578 char *p;
1579 size_t ai_size, ai_i, size;
1580
1581 p = buffer;
1582 memcpy(&ai_size, p, sizeof(size_t));
1583 p += sizeof(size_t);
1584
1585 result = NULL;
1586 lasts = NULL;
1587 for (ai_i = 0; ai_i < ai_size; ++ai_i) {
1588 memcpy(&new_ai, p, sizeof(struct addrinfo));
1589 p += sizeof(struct addrinfo);
1590 size = new_ai.ai_addrlen + sizeof(struct addrinfo) +
1591 _ALIGNBYTES;
1592
1593 sentinel = (struct addrinfo *)malloc(size);
1594 memset(sentinel, 0, size);
1595
1596 memcpy(sentinel, &new_ai, sizeof(struct addrinfo));
1597 sentinel->ai_addr = (struct sockaddr *)_ALIGN((char *)sentinel +
1598 sizeof(struct addrinfo));
1599
1600 memcpy(sentinel->ai_addr, p, new_ai.ai_addrlen);
1601 p += new_ai.ai_addrlen;
1602
1603 if (new_ai.ai_canonname != NULL) {
1604 memcpy(&size, p, sizeof(size_t));
1605 p += sizeof(size_t);
1606
1607 sentinel->ai_canonname = (char *)malloc(size + 1);
1608 memset(sentinel->ai_canonname, 0, size + 1);
1609
1610 memcpy(sentinel->ai_canonname, p, size);
1611 p += size;
1612 }
1613
1614 if (result == NULL) {
1615 result = sentinel;
1616 lasts = sentinel;
1617 } else {
1618 lasts->ai_next = sentinel;
1619 lasts = sentinel;
1620 }
1621 }
1622
1623 *((struct addrinfo **)retval) = result;
1624 return (NS_SUCCESS);
1625 }
1626 #endif /* NS_CACHING */
1627
1628 /*
1629 * FQDN hostname, DNS lookup
1630 */
1631 static int
1632 explore_fqdn(const struct addrinfo *pai, const char *hostname,
1633 const char *servname, struct addrinfo **res)
1634 {
1635 struct addrinfo *result;
1636 struct addrinfo *cur;
1637 int error = 0;
1638
1639 #ifdef NS_CACHING
1640 static const nss_cache_info cache_info =
1641 NS_COMMON_CACHE_INFO_INITIALIZER(
1642 hosts, NULL, addrinfo_id_func, addrinfo_marshal_func,
1643 addrinfo_unmarshal_func);
1644 #endif
1645 static const ns_dtab dtab[] = {
1646 NS_FILES_CB(_files_getaddrinfo, NULL)
1647 { NSSRC_DNS, _dns_getaddrinfo, NULL }, /* force -DHESIOD */
1648 NS_NIS_CB(_yp_getaddrinfo, NULL)
1649 #ifdef NS_CACHING
1650 NS_CACHE_CB(&cache_info)
1651 #endif
1652 { 0 }
1653 };
1654
1655 result = NULL;
1656
1657 /*
1658 * if the servname does not match socktype/protocol, ignore it.
1659 */
1660 if (get_portmatch(pai, servname) != 0)
1661 return 0;
1662
1663 switch (_nsdispatch(&result, dtab, NSDB_HOSTS, "getaddrinfo",
1664 default_dns_files, hostname, pai)) {
1665 case NS_TRYAGAIN:
1666 error = EAI_AGAIN;
1667 goto free;
1668 case NS_UNAVAIL:
1669 error = EAI_FAIL;
1670 goto free;
1671 case NS_NOTFOUND:
1672 error = EAI_NONAME;
1673 goto free;
1674 case NS_SUCCESS:
1675 error = 0;
1676 for (cur = result; cur; cur = cur->ai_next) {
1677 GET_PORT(cur, servname);
1678 /* canonname should be filled already */
1679 }
1680 break;
1681 }
1682
1683 *res = result;
1684
1685 return 0;
1686
1687 free:
1688 if (result)
1689 freeaddrinfo(result);
1690 return error;
1691 }
1692
1693 #ifdef DEBUG
1694 static const char AskedForGot[] =
1695 "gethostby*.getanswer: asked for \"%s\", got \"%s\"";
1696 #endif
1697
1698 static struct addrinfo *
1699 getanswer(const querybuf *answer, int anslen, const char *qname, int qtype,
1700 const struct addrinfo *pai, res_state res)
1701 {
1702 struct addrinfo sentinel, *cur;
1703 struct addrinfo ai;
1704 const struct afd *afd;
1705 char *canonname;
1706 const HEADER *hp;
1707 const u_char *cp;
1708 int n;
1709 const u_char *eom;
1710 char *bp, *ep;
1711 int type, class, ancount, qdcount;
1712 int haveanswer, had_error;
1713 char tbuf[MAXDNAME];
1714 int (*name_ok)(const char *);
1715 char hostbuf[8*1024];
1716
1717 memset(&sentinel, 0, sizeof(sentinel));
1718 cur = &sentinel;
1719
1720 canonname = NULL;
1721 eom = answer->buf + anslen;
1722 switch (qtype) {
1723 case T_A:
1724 case T_AAAA:
1725 case T_ANY: /*use T_ANY only for T_A/T_AAAA lookup*/
1726 name_ok = res_hnok;
1727 break;
1728 default:
1729 return (NULL); /* XXX should be abort(); */
1730 }
1731 /*
1732 * find first satisfactory answer
1733 */
1734 hp = &answer->hdr;
1735 ancount = ntohs(hp->ancount);
1736 qdcount = ntohs(hp->qdcount);
1737 bp = hostbuf;
1738 ep = hostbuf + sizeof hostbuf;
1739 cp = answer->buf + HFIXEDSZ;
1740 if (qdcount != 1) {
1741 RES_SET_H_ERRNO(res, NO_RECOVERY);
1742 return (NULL);
1743 }
1744 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1745 if ((n < 0) || !(*name_ok)(bp)) {
1746 RES_SET_H_ERRNO(res, NO_RECOVERY);
1747 return (NULL);
1748 }
1749 cp += n + QFIXEDSZ;
1750 if (qtype == T_A || qtype == T_AAAA || qtype == T_ANY) {
1751 /* res_send() has already verified that the query name is the
1752 * same as the one we sent; this just gets the expanded name
1753 * (i.e., with the succeeding search-domain tacked on).
1754 */
1755 n = strlen(bp) + 1; /* for the \0 */
1756 if (n >= MAXHOSTNAMELEN) {
1757 RES_SET_H_ERRNO(res, NO_RECOVERY);
1758 return (NULL);
1759 }
1760 canonname = bp;
1761 bp += n;
1762 /* The qname can be abbreviated, but h_name is now absolute. */
1763 qname = canonname;
1764 }
1765 haveanswer = 0;
1766 had_error = 0;
1767 while (ancount-- > 0 && cp < eom && !had_error) {
1768 n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
1769 if ((n < 0) || !(*name_ok)(bp)) {
1770 had_error++;
1771 continue;
1772 }
1773 cp += n; /* name */
1774 type = _getshort(cp);
1775 cp += INT16SZ; /* type */
1776 class = _getshort(cp);
1777 cp += INT16SZ + INT32SZ; /* class, TTL */
1778 n = _getshort(cp);
1779 cp += INT16SZ; /* len */
1780 if (class != C_IN) {
1781 /* XXX - debug? syslog? */
1782 cp += n;
1783 continue; /* XXX - had_error++ ? */
1784 }
1785 if ((qtype == T_A || qtype == T_AAAA || qtype == T_ANY) &&
1786 type == T_CNAME) {
1787 n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
1788 if ((n < 0) || !(*name_ok)(tbuf)) {
1789 had_error++;
1790 continue;
1791 }
1792 cp += n;
1793 /* Get canonical name. */
1794 n = strlen(tbuf) + 1; /* for the \0 */
1795 if (n > ep - bp || n >= MAXHOSTNAMELEN) {
1796 had_error++;
1797 continue;
1798 }
1799 strlcpy(bp, tbuf, ep - bp);
1800 canonname = bp;
1801 bp += n;
1802 continue;
1803 }
1804 if (qtype == T_ANY) {
1805 if (!(type == T_A || type == T_AAAA)) {
1806 cp += n;
1807 continue;
1808 }
1809 } else if (type != qtype) {
1810 #ifdef DEBUG
1811 if (type != T_KEY && type != T_SIG)
1812 syslog(LOG_NOTICE|LOG_AUTH,
1813 "gethostby*.getanswer: asked for \"%s %s %s\", got type \"%s\"",
1814 qname, p_class(C_IN), p_type(qtype),
1815 p_type(type));
1816 #endif
1817 cp += n;
1818 continue; /* XXX - had_error++ ? */
1819 }
1820 switch (type) {
1821 case T_A:
1822 case T_AAAA:
1823 if (strcasecmp(canonname, bp) != 0) {
1824 #ifdef DEBUG
1825 syslog(LOG_NOTICE|LOG_AUTH,
1826 AskedForGot, canonname, bp);
1827 #endif
1828 cp += n;
1829 continue; /* XXX - had_error++ ? */
1830 }
1831 if (type == T_A && n != INADDRSZ) {
1832 cp += n;
1833 continue;
1834 }
1835 if (type == T_AAAA && n != IN6ADDRSZ) {
1836 cp += n;
1837 continue;
1838 }
1839 #ifdef FILTER_V4MAPPED
1840 if (type == T_AAAA) {
1841 struct in6_addr in6;
1842 memcpy(&in6, cp, sizeof(in6));
1843 if (IN6_IS_ADDR_V4MAPPED(&in6)) {
1844 cp += n;
1845 continue;
1846 }
1847 }
1848 #endif
1849 if (!haveanswer) {
1850 int nn;
1851
1852 canonname = bp;
1853 nn = strlen(bp) + 1; /* for the \0 */
1854 bp += nn;
1855 }
1856
1857 /* don't overwrite pai */
1858 ai = *pai;
1859 ai.ai_family = (type == T_A) ? AF_INET : AF_INET6;
1860 afd = find_afd(ai.ai_family);
1861 if (afd == NULL) {
1862 cp += n;
1863 continue;
1864 }
1865 cur->ai_next = get_ai(&ai, afd, (const char *)cp);
1866 if (cur->ai_next == NULL)
1867 had_error++;
1868 while (cur && cur->ai_next)
1869 cur = cur->ai_next;
1870 cp += n;
1871 break;
1872 default:
1873 abort();
1874 }
1875 if (!had_error)
1876 haveanswer++;
1877 }
1878 if (haveanswer) {
1879 #if defined(RESOLVSORT)
1880 /*
1881 * We support only IPv4 address for backward
1882 * compatibility against gethostbyname(3).
1883 */
1884 if (res->nsort && qtype == T_A) {
1885 if (addr4sort(&sentinel, res) < 0) {
1886 freeaddrinfo(sentinel.ai_next);
1887 RES_SET_H_ERRNO(res, NO_RECOVERY);
1888 return NULL;
1889 }
1890 }
1891 #endif /*RESOLVSORT*/
1892 if (!canonname)
1893 get_canonname(pai, sentinel.ai_next, qname);
1894 else
1895 get_canonname(pai, sentinel.ai_next, canonname);
1896 RES_SET_H_ERRNO(res, NETDB_SUCCESS);
1897 return sentinel.ai_next;
1898 }
1899
1900 RES_SET_H_ERRNO(res, NO_RECOVERY);
1901 return NULL;
1902 }
1903
1904 #ifdef RESOLVSORT
1905 struct addr_ptr {
1906 struct addrinfo *ai;
1907 int aval;
1908 };
1909
1910 static int
1911 addr4sort(struct addrinfo *sentinel, res_state res)
1912 {
1913 struct addrinfo *ai;
1914 struct addr_ptr *addrs, addr;
1915 struct sockaddr_in *sin;
1916 int naddrs, i, j;
1917 int needsort = 0;
1918
1919 if (!sentinel)
1920 return -1;
1921 naddrs = 0;
1922 for (ai = sentinel->ai_next; ai; ai = ai->ai_next)
1923 naddrs++;
1924 if (naddrs < 2)
1925 return 0; /* We don't need sorting. */
1926 if ((addrs = malloc(sizeof(struct addr_ptr) * naddrs)) == NULL)
1927 return -1;
1928 i = 0;
1929 for (ai = sentinel->ai_next; ai; ai = ai->ai_next) {
1930 sin = (struct sockaddr_in *)ai->ai_addr;
1931 for (j = 0; (unsigned)j < res->nsort; j++) {
1932 if (res->sort_list[j].addr.s_addr ==
1933 (sin->sin_addr.s_addr & res->sort_list[j].mask))
1934 break;
1935 }
1936 addrs[i].ai = ai;
1937 addrs[i].aval = j;
1938 if (needsort == 0 && i > 0 && j < addrs[i - 1].aval)
1939 needsort = i;
1940 i++;
1941 }
1942 if (!needsort) {
1943 free(addrs);
1944 return 0;
1945 }
1946
1947 while (needsort < naddrs) {
1948 for (j = needsort - 1; j >= 0; j--) {
1949 if (addrs[j].aval > addrs[j+1].aval) {
1950 addr = addrs[j];
1951 addrs[j] = addrs[j + 1];
1952 addrs[j + 1] = addr;
1953 } else
1954 break;
1955 }
1956 needsort++;
1957 }
1958
1959 ai = sentinel;
1960 for (i = 0; i < naddrs; ++i) {
1961 ai->ai_next = addrs[i].ai;
1962 ai = ai->ai_next;
1963 }
1964 ai->ai_next = NULL;
1965 free(addrs);
1966 return 0;
1967 }
1968 #endif /*RESOLVSORT*/
1969
1970 /*ARGSUSED*/
1971 static int
1972 _dns_getaddrinfo(void *rv, void *cb_data __unused, va_list ap)
1973 {
1974 struct addrinfo *ai;
1975 querybuf *buf, *buf2;
1976 const char *hostname;
1977 const struct addrinfo *pai;
1978 struct addrinfo sentinel, *cur;
1979 struct res_target q, q2;
1980 res_state res;
1981
1982 hostname = va_arg(ap, char *);
1983 pai = va_arg(ap, const struct addrinfo *);
1984
1985 memset(&q, 0, sizeof(q));
1986 memset(&q2, 0, sizeof(q2));
1987 memset(&sentinel, 0, sizeof(sentinel));
1988 cur = &sentinel;
1989
1990 buf = malloc(sizeof(*buf));
1991 if (!buf) {
1992 h_errno = NETDB_INTERNAL;
1993 return NS_NOTFOUND;
1994 }
1995 buf2 = malloc(sizeof(*buf2));
1996 if (!buf2) {
1997 free(buf);
1998 h_errno = NETDB_INTERNAL;
1999 return NS_NOTFOUND;
2000 }
2001
2002 switch (pai->ai_family) {
2003 case AF_UNSPEC:
2004 q.name = hostname;
2005 q.qclass = C_IN;
2006 q.qtype = T_A;
2007 q.answer = buf->buf;
2008 q.anslen = sizeof(buf->buf);
2009 q.next = &q2;
2010 q2.name = hostname;
2011 q2.qclass = C_IN;
2012 q2.qtype = T_AAAA;
2013 q2.answer = buf2->buf;
2014 q2.anslen = sizeof(buf2->buf);
2015 break;
2016 case AF_INET:
2017 q.name = hostname;
2018 q.qclass = C_IN;
2019 q.qtype = T_A;
2020 q.answer = buf->buf;
2021 q.anslen = sizeof(buf->buf);
2022 break;
2023 case AF_INET6:
2024 q.name = hostname;
2025 q.qclass = C_IN;
2026 q.qtype = T_AAAA;
2027 q.answer = buf->buf;
2028 q.anslen = sizeof(buf->buf);
2029 break;
2030 default:
2031 free(buf);
2032 free(buf2);
2033 return NS_UNAVAIL;
2034 }
2035
2036 res = __res_state();
2037 if ((res->options & RES_INIT) == 0 && res_ninit(res) == -1) {
2038 RES_SET_H_ERRNO(res, NETDB_INTERNAL);
2039 free(buf);
2040 free(buf2);
2041 return NS_NOTFOUND;
2042 }
2043
2044 if (res_searchN(hostname, &q, res) < 0) {
2045 free(buf);
2046 free(buf2);
2047 return NS_NOTFOUND;
2048 }
2049 /* prefer IPv6 */
2050 if (q.next) {
2051 ai = getanswer(buf2, q2.n, q2.name, q2.qtype, pai, res);
2052 if (ai) {
2053 cur->ai_next = ai;
2054 while (cur && cur->ai_next)
2055 cur = cur->ai_next;
2056 }
2057 }
2058 ai = getanswer(buf, q.n, q.name, q.qtype, pai, res);
2059 if (ai)
2060 cur->ai_next = ai;
2061 free(buf);
2062 free(buf2);
2063 if (sentinel.ai_next == NULL)
2064 switch (res->res_h_errno) {
2065 case HOST_NOT_FOUND:
2066 return NS_NOTFOUND;
2067 case TRY_AGAIN:
2068 return NS_TRYAGAIN;
2069 default:
2070 return NS_UNAVAIL;
2071 }
2072 *((struct addrinfo **)rv) = sentinel.ai_next;
2073 return NS_SUCCESS;
2074 }
2075
2076 static void
2077 _sethtent(FILE **hostf)
2078 {
2079 if (!*hostf)
2080 *hostf = fopen(_PATH_HOSTS, "r");
2081 else
2082 rewind(*hostf);
2083 }
2084
2085 static void
2086 _endhtent(FILE **hostf)
2087 {
2088 if (*hostf) {
2089 fclose(*hostf);
2090 *hostf = NULL;
2091 }
2092 }
2093
2094 static struct addrinfo *
2095 _gethtent(FILE **hostf, const char *name, const struct addrinfo *pai)
2096 {
2097 char *p;
2098 char *cp, *tname, *cname;
2099 struct addrinfo hints, *res0, *res;
2100 int error;
2101 const char *addr;
2102 char hostbuf[8*1024];
2103
2104 if (!*hostf && !(*hostf = fopen(_PATH_HOSTS, "r")))
2105 return (NULL);
2106 again:
2107 if (!(p = fgets(hostbuf, sizeof hostbuf, *hostf)))
2108 return (NULL);
2109 if (*p == '#')
2110 goto again;
2111 cp = strpbrk(p, "#\n");
2112 if (cp != NULL)
2113 *cp = '\0';
2114 if (!(cp = strpbrk(p, " \t")))
2115 goto again;
2116 *cp++ = '\0';
2117 addr = p;
2118 cname = NULL;
2119 /* if this is not something we're looking for, skip it. */
2120 while (cp && *cp) {
2121 if (*cp == ' ' || *cp == '\t') {
2122 cp++;
2123 continue;
2124 }
2125 tname = cp;
2126 if (cname == NULL)
2127 cname = cp;
2128 if ((cp = strpbrk(cp, " \t")) != NULL)
2129 *cp++ = '\0';
2130 if (strcasecmp(name, tname) == 0)
2131 goto found;
2132 }
2133 goto again;
2134
2135 found:
2136 /* we should not glob socktype/protocol here */
2137 memset(&hints, 0, sizeof(hints));
2138 hints.ai_family = pai->ai_family;
2139 hints.ai_socktype = SOCK_DGRAM;
2140 hints.ai_protocol = 0;
2141 hints.ai_flags = AI_NUMERICHOST;
2142 error = getaddrinfo(addr, "0", &hints, &res0);
2143 if (error)
2144 goto again;
2145 #ifdef FILTER_V4MAPPED
2146 /* XXX should check all items in the chain */
2147 if (res0->ai_family == AF_INET6 &&
2148 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)res0->ai_addr)->sin6_addr)) {
2149 freeaddrinfo(res0);
2150 goto again;
2151 }
2152 #endif
2153 for (res = res0; res; res = res->ai_next) {
2154 /* cover it up */
2155 res->ai_flags = pai->ai_flags;
2156 res->ai_socktype = pai->ai_socktype;
2157 res->ai_protocol = pai->ai_protocol;
2158
2159 if (pai->ai_flags & AI_CANONNAME) {
2160 if (get_canonname(pai, res, cname) != 0) {
2161 freeaddrinfo(res0);
2162 goto again;
2163 }
2164 }
2165 }
2166 return res0;
2167 }
2168
2169 /*ARGSUSED*/
2170 static int
2171 _files_getaddrinfo(void *rv, void *cb_data __unused, va_list ap)
2172 {
2173 const char *name;
2174 const struct addrinfo *pai;
2175 struct addrinfo sentinel, *cur;
2176 struct addrinfo *p;
2177 FILE *hostf = NULL;
2178
2179 name = va_arg(ap, char *);
2180 pai = va_arg(ap, struct addrinfo *);
2181
2182 memset(&sentinel, 0, sizeof(sentinel));
2183 cur = &sentinel;
2184
2185 _sethtent(&hostf);
2186 while ((p = _gethtent(&hostf, name, pai)) != NULL) {
2187 cur->ai_next = p;
2188 while (cur && cur->ai_next)
2189 cur = cur->ai_next;
2190 }
2191 _endhtent(&hostf);
2192
2193 *((struct addrinfo **)rv) = sentinel.ai_next;
2194 if (sentinel.ai_next == NULL)
2195 return NS_NOTFOUND;
2196 return NS_SUCCESS;
2197 }
2198
2199 #ifdef YP
2200 /*ARGSUSED*/
2201 static struct addrinfo *
2202 _yphostent(char *line, const struct addrinfo *pai)
2203 {
2204 struct addrinfo sentinel, *cur;
2205 struct addrinfo hints, *res, *res0;
2206 int error;
2207 char *p = line;
2208 const char *addr, *canonname;
2209 char *nextline;
2210 char *cp;
2211
2212 addr = canonname = NULL;
2213
2214 memset(&sentinel, 0, sizeof(sentinel));
2215 cur = &sentinel;
2216
2217 nextline:
2218 /* terminate line */
2219 cp = strchr(p, '\n');
2220 if (cp) {
2221 *cp++ = '\0';
2222 nextline = cp;
2223 } else
2224 nextline = NULL;
2225
2226 cp = strpbrk(p, " \t");
2227 if (cp == NULL) {
2228 if (canonname == NULL)
2229 return (NULL);
2230 else
2231 goto done;
2232 }
2233 *cp++ = '\0';
2234
2235 addr = p;
2236
2237 while (cp && *cp) {
2238 if (*cp == ' ' || *cp == '\t') {
2239 cp++;
2240 continue;
2241 }
2242 if (!canonname)
2243 canonname = cp;
2244 if ((cp = strpbrk(cp, " \t")) != NULL)
2245 *cp++ = '\0';
2246 }
2247
2248 hints = *pai;
2249 hints.ai_flags = AI_NUMERICHOST;
2250 error = getaddrinfo(addr, NULL, &hints, &res0);
2251 if (error == 0) {
2252 for (res = res0; res; res = res->ai_next) {
2253 /* cover it up */
2254 res->ai_flags = pai->ai_flags;
2255
2256 if (pai->ai_flags & AI_CANONNAME)
2257 get_canonname(pai, res, canonname);
2258 }
2259 } else
2260 res0 = NULL;
2261 if (res0) {
2262 cur->ai_next = res0;
2263 while (cur && cur->ai_next)
2264 cur = cur->ai_next;
2265 }
2266
2267 if (nextline) {
2268 p = nextline;
2269 goto nextline;
2270 }
2271
2272 done:
2273 return sentinel.ai_next;
2274 }
2275
2276 /*ARGSUSED*/
2277 static int
2278 _yp_getaddrinfo(void *rv, void *cb_data __unused, va_list ap)
2279 {
2280 struct addrinfo sentinel, *cur;
2281 struct addrinfo *ai = NULL;
2282 char *ypbuf;
2283 int ypbuflen, r;
2284 const char *name;
2285 const struct addrinfo *pai;
2286 char *ypdomain;
2287
2288 if (_yp_check(&ypdomain) == 0)
2289 return NS_UNAVAIL;
2290
2291 name = va_arg(ap, char *);
2292 pai = va_arg(ap, const struct addrinfo *);
2293
2294 memset(&sentinel, 0, sizeof(sentinel));
2295 cur = &sentinel;
2296
2297 /* hosts.byname is only for IPv4 (Solaris8) */
2298 if (pai->ai_family == PF_UNSPEC || pai->ai_family == PF_INET) {
2299 r = yp_match(ypdomain, "hosts.byname", name,
2300 (int)strlen(name), &ypbuf, &ypbuflen);
2301 if (r == 0) {
2302 struct addrinfo ai4;
2303
2304 ai4 = *pai;
2305 ai4.ai_family = AF_INET;
2306 ai = _yphostent(ypbuf, &ai4);
2307 if (ai) {
2308 cur->ai_next = ai;
2309 while (cur && cur->ai_next)
2310 cur = cur->ai_next;
2311 }
2312 free(ypbuf);
2313 }
2314 }
2315
2316 /* ipnodes.byname can hold both IPv4/v6 */
2317 r = yp_match(ypdomain, "ipnodes.byname", name,
2318 (int)strlen(name), &ypbuf, &ypbuflen);
2319 if (r == 0) {
2320 ai = _yphostent(ypbuf, pai);
2321 if (ai)
2322 cur->ai_next = ai;
2323 free(ypbuf);
2324 }
2325
2326 if (sentinel.ai_next == NULL) {
2327 RES_SET_H_ERRNO(__res_state(), HOST_NOT_FOUND);
2328 return NS_NOTFOUND;
2329 }
2330 *((struct addrinfo **)rv) = sentinel.ai_next;
2331 return NS_SUCCESS;
2332 }
2333 #endif
2334
2335 /* resolver logic */
2336
2337 /*
2338 * Formulate a normal query, send, and await answer.
2339 * Returned answer is placed in supplied buffer "answer".
2340 * Perform preliminary check of answer, returning success only
2341 * if no error is indicated and the answer count is nonzero.
2342 * Return the size of the response on success, -1 on error.
2343 * Error number is left in h_errno.
2344 *
2345 * Caller must parse answer and determine whether it answers the question.
2346 */
2347 static int
2348 res_queryN(const char *name, struct res_target *target, res_state res)
2349 {
2350 u_char *buf;
2351 HEADER *hp;
2352 int n;
2353 u_int oflags;
2354 struct res_target *t;
2355 int rcode;
2356 int ancount;
2357
2358 rcode = NOERROR;
2359 ancount = 0;
2360
2361 buf = malloc(MAXPACKET);
2362 if (!buf) {
2363 RES_SET_H_ERRNO(res, NETDB_INTERNAL);
2364 return -1;
2365 }
2366
2367 for (t = target; t; t = t->next) {
2368 int class, type;
2369 u_char *answer;
2370 int anslen;
2371
2372 hp = (HEADER *)(void *)t->answer;
2373
2374 /* make it easier... */
2375 class = t->qclass;
2376 type = t->qtype;
2377 answer = t->answer;
2378 anslen = t->anslen;
2379
2380 oflags = res->_flags;
2381
2382 again:
2383 hp->rcode = NOERROR; /* default */
2384
2385 #ifdef DEBUG
2386 if (res->options & RES_DEBUG)
2387 printf(";; res_query(%s, %d, %d)\n", name, class, type);
2388 #endif
2389
2390 n = res_nmkquery(res, QUERY, name, class, type, NULL, 0, NULL,
2391 buf, MAXPACKET);
2392 if (n > 0 && (res->_flags & RES_F_EDNS0ERR) == 0 &&
2393 (res->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0U)
2394 n = res_nopt(res, n, buf, MAXPACKET, anslen);
2395 if (n <= 0) {
2396 #ifdef DEBUG
2397 if (res->options & RES_DEBUG)
2398 printf(";; res_query: mkquery failed\n");
2399 #endif
2400 free(buf);
2401 RES_SET_H_ERRNO(res, NO_RECOVERY);
2402 return (n);
2403 }
2404 n = res_nsend(res, buf, n, answer, anslen);
2405 if (n < 0) {
2406 /*
2407 * if the query choked with EDNS0, retry
2408 * without EDNS0
2409 */
2410 if ((res->options & (RES_USE_EDNS0|RES_USE_DNSSEC))
2411 != 0U &&
2412 ((oflags ^ res->_flags) & RES_F_EDNS0ERR) != 0) {
2413 res->_flags |= RES_F_EDNS0ERR;
2414 if (res->options & RES_DEBUG)
2415 printf(";; res_nquery: retry without EDNS0\n");
2416 goto again;
2417 }
2418 rcode = hp->rcode; /* record most recent error */
2419 #ifdef DEBUG
2420 if (res->options & RES_DEBUG)
2421 printf(";; res_query: send error\n");
2422 #endif
2423 continue;
2424 }
2425
2426 if (n > anslen)
2427 hp->rcode = FORMERR; /* XXX not very informative */
2428 if (hp->rcode != NOERROR || ntohs(hp->ancount) == 0) {
2429 rcode = hp->rcode; /* record most recent error */
2430 #ifdef DEBUG
2431 if (res->options & RES_DEBUG)
2432 printf(";; rcode = %u, ancount=%u\n", hp->rcode,
2433 ntohs(hp->ancount));
2434 #endif
2435 continue;
2436 }
2437
2438 ancount += ntohs(hp->ancount);
2439
2440 t->n = n;
2441 }
2442
2443 free(buf);
2444
2445 if (ancount == 0) {
2446 switch (rcode) {
2447 case NXDOMAIN:
2448 RES_SET_H_ERRNO(res, HOST_NOT_FOUND);
2449 break;
2450 case SERVFAIL:
2451 RES_SET_H_ERRNO(res, TRY_AGAIN);
2452 break;
2453 case NOERROR:
2454 RES_SET_H_ERRNO(res, NO_DATA);
2455 break;
2456 case FORMERR:
2457 case NOTIMP:
2458 case REFUSED:
2459 default:
2460 RES_SET_H_ERRNO(res, NO_RECOVERY);
2461 break;
2462 }
2463 return (-1);
2464 }
2465 return (ancount);
2466 }
2467
2468 /*
2469 * Formulate a normal query, send, and retrieve answer in supplied buffer.
2470 * Return the size of the response on success, -1 on error.
2471 * If enabled, implement search rules until answer or unrecoverable failure
2472 * is detected. Error code, if any, is left in h_errno.
2473 */
2474 static int
2475 res_searchN(const char *name, struct res_target *target, res_state res)
2476 {
2477 const char *cp, * const *domain;
2478 HEADER *hp = (HEADER *)(void *)target->answer; /*XXX*/
2479 u_int dots;
2480 int trailing_dot, ret, saved_herrno;
2481 int got_nodata = 0, got_servfail = 0, root_on_list = 0;
2482 int tried_as_is = 0;
2483 int searched = 0;
2484 char abuf[MAXDNAME];
2485
2486 errno = 0;
2487 RES_SET_H_ERRNO(res, HOST_NOT_FOUND); /* default, if we never query */
2488 dots = 0;
2489 for (cp = name; *cp; cp++)
2490 dots += (*cp == '.');
2491 trailing_dot = 0;
2492 if (cp > name && *--cp == '.')
2493 trailing_dot++;
2494
2495 /*
2496 * if there aren't any dots, it could be a user-level alias
2497 */
2498 if (!dots &&
2499 (cp = res_hostalias(res, name, abuf, sizeof(abuf))) != NULL)
2500 return (res_queryN(cp, target, res));
2501
2502 /*
2503 * If there are enough dots in the name, let's just give it a
2504 * try 'as is'. The threshold can be set with the "ndots" option.
2505 * Also, query 'as is', if there is a trailing dot in the name.
2506 */
2507 saved_herrno = -1;
2508 if (dots >= res->ndots || trailing_dot) {
2509 ret = res_querydomainN(name, NULL, target, res);
2510 if (ret > 0 || trailing_dot)
2511 return (ret);
2512 if (errno == ECONNREFUSED) {
2513 RES_SET_H_ERRNO(res, TRY_AGAIN);
2514 return (-1);
2515 }
2516 switch (res->res_h_errno) {
2517 case NO_DATA:
2518 case HOST_NOT_FOUND:
2519 break;
2520 case TRY_AGAIN:
2521 if (hp->rcode == SERVFAIL)
2522 break;
2523 /* FALLTHROUGH */
2524 default:
2525 return (-1);
2526 }
2527 saved_herrno = res->res_h_errno;
2528 tried_as_is++;
2529 }
2530
2531 /*
2532 * We do at least one level of search if
2533 * - there is no dot and RES_DEFNAME is set, or
2534 * - there is at least one dot, there is no trailing dot,
2535 * and RES_DNSRCH is set.
2536 */
2537 if ((!dots && (res->options & RES_DEFNAMES)) ||
2538 (dots && !trailing_dot && (res->options & RES_DNSRCH))) {
2539 int done = 0;
2540
2541 for (domain = (const char * const *)res->dnsrch;
2542 *domain && !done;
2543 domain++) {
2544 searched = 1;
2545
2546 if (domain[0][0] == '\0' ||
2547 (domain[0][0] == '.' && domain[0][1] == '\0'))
2548 root_on_list++;
2549
2550 if (root_on_list && tried_as_is)
2551 continue;
2552
2553 ret = res_querydomainN(name, *domain, target, res);
2554 if (ret > 0)
2555 return (ret);
2556
2557 /*
2558 * If no server present, give up.
2559 * If name isn't found in this domain,
2560 * keep trying higher domains in the search list
2561 * (if that's enabled).
2562 * On a NO_DATA error, keep trying, otherwise
2563 * a wildcard entry of another type could keep us
2564 * from finding this entry higher in the domain.
2565 * If we get some other error (negative answer or
2566 * server failure), then stop searching up,
2567 * but try the input name below in case it's
2568 * fully-qualified.
2569 */
2570 if (errno == ECONNREFUSED) {
2571 RES_SET_H_ERRNO(res, TRY_AGAIN);
2572 return (-1);
2573 }
2574
2575 switch (res->res_h_errno) {
2576 case NO_DATA:
2577 got_nodata++;
2578 /* FALLTHROUGH */
2579 case HOST_NOT_FOUND:
2580 /* keep trying */
2581 break;
2582 case TRY_AGAIN:
2583 got_servfail++;
2584 if (hp->rcode == SERVFAIL) {
2585 /* try next search element, if any */
2586 break;
2587 }
2588 /* FALLTHROUGH */
2589 default:
2590 /* anything else implies that we're done */
2591 done++;
2592 }
2593 /*
2594 * if we got here for some reason other than DNSRCH,
2595 * we only wanted one iteration of the loop, so stop.
2596 */
2597 if (!(res->options & RES_DNSRCH))
2598 done++;
2599 }
2600 }
2601
2602 switch (res->res_h_errno) {
2603 case NO_DATA:
2604 case HOST_NOT_FOUND:
2605 break;
2606 case TRY_AGAIN:
2607 if (hp->rcode == SERVFAIL)
2608 break;
2609 /* FALLTHROUGH */
2610 default:
2611 goto giveup;
2612 }
2613
2614 /*
2615 * If the query has not already been tried as is then try it
2616 * unless RES_NOTLDQUERY is set and there were no dots.
2617 */
2618 if ((dots || !searched || !(res->options & RES_NOTLDQUERY)) &&
2619 !(tried_as_is || root_on_list)) {
2620 ret = res_querydomainN(name, NULL, target, res);
2621 if (ret > 0)
2622 return (ret);
2623 }
2624
2625 /*
2626 * if we got here, we didn't satisfy the search.
2627 * if we did an initial full query, return that query's h_errno
2628 * (note that we wouldn't be here if that query had succeeded).
2629 * else if we ever got a nodata, send that back as the reason.
2630 * else send back meaningless h_errno, that being the one from
2631 * the last DNSRCH we did.
2632 */
2633 giveup:
2634 if (saved_herrno != -1)
2635 RES_SET_H_ERRNO(res, saved_herrno);
2636 else if (got_nodata)
2637 RES_SET_H_ERRNO(res, NO_DATA);
2638 else if (got_servfail)
2639 RES_SET_H_ERRNO(res, TRY_AGAIN);
2640 return (-1);
2641 }
2642
2643 /*
2644 * Perform a call on res_query on the concatenation of name and domain,
2645 * removing a trailing dot from name if domain is NULL.
2646 */
2647 static int
2648 res_querydomainN(const char *name, const char *domain,
2649 struct res_target *target, res_state res)
2650 {
2651 char nbuf[MAXDNAME];
2652 const char *longname = nbuf;
2653 size_t n, d;
2654
2655 #ifdef DEBUG
2656 if (res->options & RES_DEBUG)
2657 printf(";; res_querydomain(%s, %s)\n",
2658 name, domain?domain:"<Nil>");
2659 #endif
2660 if (domain == NULL) {
2661 /*
2662 * Check for trailing '.';
2663 * copy without '.' if present.
2664 */
2665 n = strlen(name);
2666 if (n >= MAXDNAME) {
2667 RES_SET_H_ERRNO(res, NO_RECOVERY);
2668 return (-1);
2669 }
2670 if (n > 0 && name[--n] == '.') {
2671 strncpy(nbuf, name, n);
2672 nbuf[n] = '\0';
2673 } else
2674 longname = name;
2675 } else {
2676 n = strlen(name);
2677 d = strlen(domain);
2678 if (n + d + 1 >= MAXDNAME) {
2679 RES_SET_H_ERRNO(res, NO_RECOVERY);
2680 return (-1);
2681 }
2682 snprintf(nbuf, sizeof(nbuf), "%s.%s", name, domain);
2683 }
2684 return (res_queryN(longname, target, res));
2685 }
DragonFly BSD