2 * Copyright (c) 1985, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
33 * Permission to use, copy, modify, and distribute this software for any
34 * purpose with or without fee is hereby granted, provided that the above
35 * copyright notice and this permission notice appear in all copies, and that
36 * the name of Digital Equipment Corporation not be used in advertising or
37 * publicity pertaining to distribution of the document or software without
38 * specific, written prior permission.
40 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
41 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
42 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
43 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
44 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
45 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
46 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
51 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
53 * Permission to use, copy, modify, and distribute this software for any
54 * purpose with or without fee is hereby granted, provided that the above
55 * copyright notice and this permission notice appear in all copies.
57 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
58 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
59 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
60 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
61 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
62 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
63 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
71 #include <stdio_ext.h>
76 #include <arpa/inet.h>
77 #include <arpa/nameser.h>
79 #include <netinet/in.h>
80 #include <sys/param.h>
81 #include <sys/socket.h>
83 #include <sys/types.h>
85 #include <not-cancel.h>
87 /* Options. Should all be left alone. */
90 static void res_setoptions (res_state
, const char *, const char *)
93 static const char sort_mask_chars
[] = "/&";
94 #define ISSORTMASK(ch) (strchr(sort_mask_chars, ch) != NULL)
95 static u_int32_t
net_mask (struct in_addr
) __THROW
;
97 unsigned long long int __res_initstamp attribute_hidden
;
100 * Resolver state default settings.
104 * Set up default settings. If the configuration file exist, the values
105 * there will have precedence. Otherwise, the server address is set to
106 * INADDR_LOOPBACK and the default domain name comes from gethostname.
108 * Return 0 if completes successfully, -1 on error
111 res_ninit(res_state statp
) {
112 extern int __res_vinit(res_state
, int);
114 return (__res_vinit(statp
, 0));
116 libc_hidden_def (__res_ninit
)
118 /* This function has to be reachable by res_data.c but not publically. */
120 __res_vinit(res_state statp
, int preinit
) {
125 int nserv
= 0; /* number of nameservers read from file */
131 statp
->_u
._ext
.initstamp
= __res_initstamp
;
134 statp
->retrans
= RES_TIMEOUT
;
135 statp
->retry
= RES_DFLRETRY
;
136 statp
->options
= RES_DEFAULT
;
137 statp
->id
= res_randomid();
141 statp
->defdname
[0] = '\0';
148 statp
->_u
._ext
.nscount
= 0;
149 for (n
= 0; n
< MAXNS
; n
++)
150 statp
->_u
._ext
.nsaddrs
[n
] = NULL
;
152 /* Allow user to override the local domain definition */
153 if ((cp
= getenv("LOCALDOMAIN")) != NULL
) {
154 (void)strncpy(statp
->defdname
, cp
, sizeof(statp
->defdname
) - 1);
155 statp
->defdname
[sizeof(statp
->defdname
) - 1] = '\0';
159 * Set search list to be blank-separated strings
160 * from rest of env value. Permits users of LOCALDOMAIN
161 * to still have a search list, and anyone to set the
162 * one that they want to use as an individual (even more
163 * important now that the rfc1535 stuff restricts searches)
165 cp
= statp
->defdname
;
168 for (n
= 0; *cp
&& pp
< statp
->dnsrch
+ MAXDNSRCH
; cp
++) {
169 if (*cp
== '\n') /* silly backwards compat */
171 else if (*cp
== ' ' || *cp
== '\t') {
180 /* null terminate last domain if there are excess */
181 while (*cp
!= '\0' && *cp
!= ' ' && *cp
!= '\t' && *cp
!= '\n')
187 #define MATCH(line, name) \
188 (!strncmp(line, name, sizeof(name) - 1) && \
189 (line[sizeof(name) - 1] == ' ' || \
190 line[sizeof(name) - 1] == '\t'))
192 if ((fp
= fopen(_PATH_RESCONF
, "rce")) != NULL
) {
193 /* No threads use this stream. */
194 __fsetlocking (fp
, FSETLOCKING_BYCALLER
);
195 /* read the config file */
196 while (__fgets_unlocked(buf
, sizeof(buf
), fp
) != NULL
) {
198 if (*buf
== ';' || *buf
== '#')
200 /* read default domain name */
201 if (MATCH(buf
, "domain")) {
202 if (haveenv
) /* skip if have from environ */
204 cp
= buf
+ sizeof("domain") - 1;
205 while (*cp
== ' ' || *cp
== '\t')
207 if ((*cp
== '\0') || (*cp
== '\n'))
209 strncpy(statp
->defdname
, cp
, sizeof(statp
->defdname
) - 1);
210 statp
->defdname
[sizeof(statp
->defdname
) - 1] = '\0';
211 if ((cp
= strpbrk(statp
->defdname
, " \t\n")) != NULL
)
216 /* set search list */
217 if (MATCH(buf
, "search")) {
218 if (haveenv
) /* skip if have from environ */
220 cp
= buf
+ sizeof("search") - 1;
221 while (*cp
== ' ' || *cp
== '\t')
223 if ((*cp
== '\0') || (*cp
== '\n'))
225 strncpy(statp
->defdname
, cp
, sizeof(statp
->defdname
) - 1);
226 statp
->defdname
[sizeof(statp
->defdname
) - 1] = '\0';
227 if ((cp
= strchr(statp
->defdname
, '\n')) != NULL
)
230 * Set search list to be blank-separated strings
233 cp
= statp
->defdname
;
236 for (n
= 0; *cp
&& pp
< statp
->dnsrch
+ MAXDNSRCH
; cp
++) {
237 if (*cp
== ' ' || *cp
== '\t') {
245 /* null terminate last domain if there are excess */
246 while (*cp
!= '\0' && *cp
!= ' ' && *cp
!= '\t')
253 /* read nameservers to query */
254 if (MATCH(buf
, "nameserver") && nserv
< MAXNS
) {
257 cp
= buf
+ sizeof("nameserver") - 1;
258 while (*cp
== ' ' || *cp
== '\t')
260 if ((*cp
!= '\0') && (*cp
!= '\n')
261 && __inet_aton(cp
, &a
)) {
262 statp
->nsaddr_list
[nserv
].sin_addr
= a
;
263 statp
->nsaddr_list
[nserv
].sin_family
= AF_INET
;
264 statp
->nsaddr_list
[nserv
].sin_port
=
265 htons(NAMESERVER_PORT
);
271 if ((el
= strpbrk(cp
, " \t\n")) != NULL
)
273 if ((el
= strchr(cp
, SCOPE_DELIMITER
)) != NULL
)
276 (__inet_pton(AF_INET6
, cp
, &a6
) > 0)) {
277 struct sockaddr_in6
*sa6
;
279 sa6
= malloc(sizeof(*sa6
));
281 sa6
->sin6_family
= AF_INET6
;
282 sa6
->sin6_port
= htons(NAMESERVER_PORT
);
283 sa6
->sin6_flowinfo
= 0;
286 if (__glibc_likely (el
== NULL
))
287 sa6
->sin6_scope_id
= 0;
289 int try_numericscope
= 1;
290 if (IN6_IS_ADDR_LINKLOCAL (&a6
)
291 || IN6_IS_ADDR_MC_LINKLOCAL (&a6
)) {
293 = __if_nametoindex (el
+ 1);
294 if (sa6
->sin6_scope_id
!= 0)
295 try_numericscope
= 0;
298 if (try_numericscope
) {
301 = (uint32_t) strtoul (el
+ 1, &end
,
304 sa6
->sin6_scope_id
= 0;
308 statp
->nsaddr_list
[nserv
].sin_family
= 0;
309 statp
->_u
._ext
.nsaddrs
[nserv
] = sa6
;
310 statp
->_u
._ext
.nssocks
[nserv
] = -1;
318 if (MATCH(buf
, "sortlist")) {
321 cp
= buf
+ sizeof("sortlist") - 1;
322 while (nsort
< MAXRESOLVSORT
) {
323 while (*cp
== ' ' || *cp
== '\t')
325 if (*cp
== '\0' || *cp
== '\n' || *cp
== ';')
328 while (*cp
&& !ISSORTMASK(*cp
) && *cp
!= ';' &&
329 isascii(*cp
) && !isspace(*cp
))
333 if (__inet_aton(net
, &a
)) {
334 statp
->sort_list
[nsort
].addr
= a
;
338 while (*cp
&& *cp
!= ';' &&
339 isascii(*cp
) && !isspace(*cp
))
343 if (__inet_aton(net
, &a
)) {
344 statp
->sort_list
[nsort
].mask
= a
.s_addr
;
346 statp
->sort_list
[nsort
].mask
=
347 net_mask(statp
->sort_list
[nsort
].addr
);
350 statp
->sort_list
[nsort
].mask
=
351 net_mask(statp
->sort_list
[nsort
].addr
);
359 if (MATCH(buf
, "options")) {
360 res_setoptions(statp
, buf
+ sizeof("options") - 1, "conf");
364 statp
->nscount
= nserv
;
366 /* We try IPv6 servers again. */
367 statp
->ipv6_unavail
= false;
369 statp
->nsort
= nsort
;
372 if (__builtin_expect(statp
->nscount
== 0, 0)) {
373 statp
->nsaddr
.sin_addr
= __inet_makeaddr(IN_LOOPBACKNET
, 1);
374 statp
->nsaddr
.sin_family
= AF_INET
;
375 statp
->nsaddr
.sin_port
= htons(NAMESERVER_PORT
);
378 if (statp
->defdname
[0] == 0 &&
379 __gethostname(buf
, sizeof(statp
->defdname
) - 1) == 0 &&
380 (cp
= strchr(buf
, '.')) != NULL
)
381 strcpy(statp
->defdname
, cp
+ 1);
383 /* find components of local domain that might be searched */
384 if (havesearch
== 0) {
386 *pp
++ = statp
->defdname
;
391 if ((cp
= getenv("RES_OPTIONS")) != NULL
)
392 res_setoptions(statp
, cp
, "env");
393 statp
->options
|= RES_INIT
;
399 res_setoptions(res_state statp
, const char *options
, const char *source
) {
400 const char *cp
= options
;
404 if (statp
->options
& RES_DEBUG
)
405 printf(";; res_setoptions(\"%s\", \"%s\")...\n",
409 /* skip leading and inner runs of spaces */
410 while (*cp
== ' ' || *cp
== '\t')
412 /* search for and process individual options */
413 if (!strncmp(cp
, "ndots:", sizeof("ndots:") - 1)) {
414 i
= atoi(cp
+ sizeof("ndots:") - 1);
415 if (i
<= RES_MAXNDOTS
)
418 statp
->ndots
= RES_MAXNDOTS
;
420 if (statp
->options
& RES_DEBUG
)
421 printf(";;\tndots=%d\n", statp
->ndots
);
423 } else if (!strncmp(cp
, "timeout:", sizeof("timeout:") - 1)) {
424 i
= atoi(cp
+ sizeof("timeout:") - 1);
425 if (i
<= RES_MAXRETRANS
)
428 statp
->retrans
= RES_MAXRETRANS
;
429 } else if (!strncmp(cp
, "attempts:", sizeof("attempts:") - 1)){
430 i
= atoi(cp
+ sizeof("attempts:") - 1);
431 if (i
<= RES_MAXRETRY
)
434 statp
->retry
= RES_MAXRETRY
;
435 } else if (!strncmp(cp
, "debug", sizeof("debug") - 1)) {
437 if (!(statp
->options
& RES_DEBUG
)) {
438 printf(";; res_setoptions(\"%s\", \"%s\")..\n",
440 statp
->options
|= RES_DEBUG
;
442 printf(";;\tdebug\n");
450 unsigned long int flag
;
452 #define STRnLEN(str) str, sizeof (str) - 1
453 { STRnLEN ("inet6"), 0, RES_USE_INET6
},
454 { STRnLEN ("ip6-bytestring"), 0, RES_USEBSTRING
},
455 { STRnLEN ("no-ip6-dotint"), 0, RES_NOIP6DOTINT
},
456 { STRnLEN ("ip6-dotint"), 1, ~RES_NOIP6DOTINT
},
457 { STRnLEN ("rotate"), 0, RES_ROTATE
},
458 { STRnLEN ("no-check-names"), 0, RES_NOCHECKNAME
},
459 { STRnLEN ("edns0"), 0, RES_USE_EDNS0
},
460 { STRnLEN ("single-request-reopen"), 0, RES_SNGLKUPREOP
},
461 { STRnLEN ("single-request"), 0, RES_SNGLKUP
},
462 { STRnLEN ("no_tld_query"), 0, RES_NOTLDQUERY
},
463 { STRnLEN ("no-tld-query"), 0, RES_NOTLDQUERY
},
464 { STRnLEN ("use-vc"), 0, RES_USEVC
}
466 #define noptions (sizeof (options) / sizeof (options[0]))
468 for (i
= 0; i
< noptions
; ++i
)
469 if (strncmp (cp
, options
[i
].str
, options
[i
].len
) == 0)
471 if (options
[i
].clear
)
472 statp
->options
&= options
[i
].flag
;
474 statp
->options
|= options
[i
].flag
;
478 /* XXX - print a warning here? */
481 /* skip to next run of spaces */
482 while (*cp
&& *cp
!= ' ' && *cp
!= '\t')
487 /* XXX - should really support CIDR which means explicit masks always. */
488 /* XXX - should really use system's version of this */
490 net_mask (struct in_addr in
)
492 u_int32_t i
= ntohl(in
.s_addr
);
495 return (htonl(IN_CLASSA_NET
));
496 else if (IN_CLASSB(i
))
497 return (htonl(IN_CLASSB_NET
));
498 return (htonl(IN_CLASSC_NET
));
503 return 0xffff & __getpid();
505 libc_hidden_def (__res_randomid
)
509 * This routine is for closing the socket if a virtual circuit is used and
510 * the program wants to close it. This provides support for endhostent()
511 * which expects to close the socket.
513 * This routine is not expected to be user visible.
516 __res_iclose(res_state statp
, bool free_addr
) {
519 if (statp
->_vcsock
>= 0) {
520 close_not_cancel_no_status(statp
->_vcsock
);
522 statp
->_flags
&= ~(RES_F_VC
| RES_F_CONN
);
524 for (ns
= 0; ns
< statp
->nscount
; ns
++)
525 if (statp
->_u
._ext
.nsaddrs
[ns
]) {
526 if (statp
->_u
._ext
.nssocks
[ns
] != -1) {
527 close_not_cancel_no_status(statp
->_u
._ext
.nssocks
[ns
]);
528 statp
->_u
._ext
.nssocks
[ns
] = -1;
531 free (statp
->_u
._ext
.nsaddrs
[ns
]);
532 statp
->_u
._ext
.nsaddrs
[ns
] = NULL
;
536 libc_hidden_def (__res_iclose
)
539 res_nclose(res_state statp
)
541 __res_iclose (statp
, true);
543 libc_hidden_def (__res_nclose
)
545 #ifdef _LIBC_REENTRANT
546 /* This is called when a thread is exiting to free resources held in _res. */
547 static void __attribute__ ((section ("__libc_thread_freeres_fn")))
548 res_thread_freeres (void)
550 if (_res
.nscount
== 0)
551 /* Never called res_ninit. */
554 __res_iclose (&_res
, true); /* Close any VC sockets. */
556 /* Make sure we do a full re-initialization the next time. */
559 text_set_element (__libc_thread_subfreeres
, res_thread_freeres
);
560 text_set_element (__libc_subfreeres
, res_thread_freeres
);