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
67 #if defined(LIBC_SCCS) && !defined(lint)
68 static const char sccsid
[] = "@(#)res_init.c 8.1 (Berkeley) 6/7/93";
69 static const char rcsid
[] = "$BINDId: res_init.c,v 8.16 2000/05/09 07:10:12 vixie Exp $";
70 #endif /* LIBC_SCCS and not lint */
72 #include <sys/types.h>
73 #include <sys/param.h>
74 #include <sys/socket.h>
77 #include <netinet/in.h>
78 #include <arpa/inet.h>
79 #include <arpa/nameser.h>
84 #include <stdio_ext.h>
89 /* Options. Should all be left alone. */
94 static void res_setoptions (res_state
, const char *, const char *)
98 static const char sort_mask
[] = "/&";
99 #define ISSORTMASK(ch) (strchr(sort_mask, ch) != NULL)
100 static u_int32_t net_mask
__P((struct in_addr
));
103 #if !defined(isascii) /* XXX - could be a function */
104 # define isascii(c) (!(c & 0200))
108 * Resolver state default settings.
112 * Set up default settings. If the configuration file exist, the values
113 * there will have precedence. Otherwise, the server address is set to
114 * INADDR_ANY and the default domain name comes from the gethostname().
116 * An interrim version of this code (BIND 4.9, pre-4.4BSD) used 127.0.0.1
117 * rather than INADDR_ANY ("0.0.0.0") as the default name server address
118 * since it was noted that INADDR_ANY actually meant ``the first interface
119 * you "ifconfig"'d at boot time'' and if this was a SLIP or PPP interface,
120 * it had to be "up" in order for you to reach your own name server. It
121 * was later decided that since the recommended practice is to always
122 * install local static routes through 127.0.0.1 for all your network
123 * interfaces, that we could solve this problem without a code change.
125 * The configuration file should always be used, since it is the only way
126 * to specify a default domain. If you are running a server on your local
127 * machine, you should say "nameserver 0.0.0.0" or "nameserver 127.0.0.1"
128 * in the configuration file.
130 * Return 0 if completes successfully, -1 on error
133 res_ninit(res_state statp
) {
134 extern int __res_vinit(res_state
, int);
136 return (__res_vinit(statp
, 0));
139 /* This function has to be reachable by res_data.c but not publically. */
141 __res_vinit(res_state statp
, int preinit
) {
143 register char *cp
, **pp
;
146 int nserv
= 0; /* number of nameserver records read from file */
148 int nservall
= 0; /* number of NS records read, nserv IPv4 only */
161 statp
->retrans
= RES_TIMEOUT
;
162 statp
->retry
= RES_DFLRETRY
;
163 statp
->options
= RES_DEFAULT
;
164 statp
->id
= res_randomid();
168 statp
->nsaddr
.sin_addr
= inet_makeaddr(IN_LOOPBACKNET
, 1);
170 statp
->nsaddr
.sin_addr
.s_addr
= INADDR_ANY
;
172 statp
->nsaddr
.sin_family
= AF_INET
;
173 statp
->nsaddr
.sin_port
= htons(NAMESERVER_PORT
);
181 statp
->_u
._ext
.nsinit
= 0;
182 statp
->_u
._ext
.nscount
= 0;
184 statp
->_u
._ext
.nscount6
= 0;
185 for (n
= 0; n
< MAXNS
; n
++) {
186 statp
->_u
._ext
.nsaddrs
[n
] = NULL
;
187 statp
->_u
._ext
.nsmap
[n
] = MAXNS
;
191 /* Allow user to override the local domain definition */
192 if ((cp
= getenv("LOCALDOMAIN")) != NULL
) {
193 (void)strncpy(statp
->defdname
, cp
, sizeof(statp
->defdname
) - 1);
194 statp
->defdname
[sizeof(statp
->defdname
) - 1] = '\0';
198 * Set search list to be blank-separated strings
199 * from rest of env value. Permits users of LOCALDOMAIN
200 * to still have a search list, and anyone to set the
201 * one that they want to use as an individual (even more
202 * important now that the rfc1535 stuff restricts searches)
204 cp
= statp
->defdname
;
207 for (n
= 0; *cp
&& pp
< statp
->dnsrch
+ MAXDNSRCH
; cp
++) {
208 if (*cp
== '\n') /* silly backwards compat */
210 else if (*cp
== ' ' || *cp
== '\t') {
219 /* null terminate last domain if there are excess */
220 while (*cp
!= '\0' && *cp
!= ' ' && *cp
!= '\t' && *cp
!= '\n')
226 #define MATCH(line, name) \
227 (!strncmp(line, name, sizeof(name) - 1) && \
228 (line[sizeof(name) - 1] == ' ' || \
229 line[sizeof(name) - 1] == '\t'))
231 if ((fp
= fopen(_PATH_RESCONF
, "r")) != NULL
) {
232 /* No threads use this stream. */
233 __fsetlocking (fp
, FSETLOCKING_BYCALLER
);
234 /* read the config file */
235 while (fgets_unlocked(buf
, sizeof(buf
), fp
) != NULL
) {
237 if (*buf
== ';' || *buf
== '#')
239 /* read default domain name */
240 if (MATCH(buf
, "domain")) {
241 if (haveenv
) /* skip if have from environ */
243 cp
= buf
+ sizeof("domain") - 1;
244 while (*cp
== ' ' || *cp
== '\t')
246 if ((*cp
== '\0') || (*cp
== '\n'))
248 strncpy(statp
->defdname
, cp
, sizeof(statp
->defdname
) - 1);
249 statp
->defdname
[sizeof(statp
->defdname
) - 1] = '\0';
250 if ((cp
= strpbrk(statp
->defdname
, " \t\n")) != NULL
)
255 /* set search list */
256 if (MATCH(buf
, "search")) {
257 if (haveenv
) /* skip if have from environ */
259 cp
= buf
+ sizeof("search") - 1;
260 while (*cp
== ' ' || *cp
== '\t')
262 if ((*cp
== '\0') || (*cp
== '\n'))
264 strncpy(statp
->defdname
, cp
, sizeof(statp
->defdname
) - 1);
265 statp
->defdname
[sizeof(statp
->defdname
) - 1] = '\0';
266 if ((cp
= strchr(statp
->defdname
, '\n')) != NULL
)
269 * Set search list to be blank-separated strings
272 cp
= statp
->defdname
;
275 for (n
= 0; *cp
&& pp
< statp
->dnsrch
+ MAXDNSRCH
; cp
++) {
276 if (*cp
== ' ' || *cp
== '\t') {
284 /* null terminate last domain if there are excess */
285 while (*cp
!= '\0' && *cp
!= ' ' && *cp
!= '\t')
292 /* read nameservers to query */
294 if (MATCH(buf
, "nameserver") && nservall
< MAXNS
) {
296 if (MATCH(buf
, "nameserver") && nserv
< MAXNS
) {
300 cp
= buf
+ sizeof("nameserver") - 1;
301 while (*cp
== ' ' || *cp
== '\t')
303 if ((*cp
!= '\0') && (*cp
!= '\n')
304 && __inet_aton(cp
, &a
)) {
305 statp
->nsaddr_list
[nserv
].sin_addr
= a
;
306 statp
->nsaddr_list
[nserv
].sin_family
= AF_INET
;
307 statp
->nsaddr_list
[nserv
].sin_port
=
308 htons(NAMESERVER_PORT
);
316 if ((el
= strchr(cp
, '\n')) != NULL
)
319 (inet_pton(AF_INET6
, cp
, &a6
) > 0)) {
320 struct sockaddr_in6
*sa6
;
322 sa6
= malloc(sizeof(*sa6
));
325 sa6
->sin6_family
= AF_INET6
;
326 sa6
->sin6_port
= htons(NAMESERVER_PORT
);
327 statp
->_u
._ext
.nsaddrs
[nservall
] = sa6
;
328 statp
->_u
._ext
.nssocks
[nservall
] = -1;
329 statp
->_u
._ext
.nsmap
[nservall
] = MAXNS
+ 1;
338 if (MATCH(buf
, "sortlist")) {
341 cp
= buf
+ sizeof("sortlist") - 1;
342 while (nsort
< MAXRESOLVSORT
) {
343 while (*cp
== ' ' || *cp
== '\t')
345 if (*cp
== '\0' || *cp
== '\n' || *cp
== ';')
348 while (*cp
&& !ISSORTMASK(*cp
) && *cp
!= ';' &&
349 isascii(*cp
) && !isspace(*cp
))
353 if (__inet_aton(net
, &a
)) {
354 statp
->sort_list
[nsort
].addr
= a
;
358 while (*cp
&& *cp
!= ';' &&
359 isascii(*cp
) && !isspace(*cp
))
363 if (__inet_aton(net
, &a
)) {
364 statp
->sort_list
[nsort
].mask
= a
.s_addr
;
366 statp
->sort_list
[nsort
].mask
=
367 net_mask(statp
->sort_list
[nsort
].addr
);
370 statp
->sort_list
[nsort
].mask
=
371 net_mask(statp
->sort_list
[nsort
].addr
);
380 if (MATCH(buf
, "options")) {
381 res_setoptions(statp
, buf
+ sizeof("options") - 1, "conf");
386 statp
->nscount
= nserv
;
388 if (nservall
- nserv
> 0)
389 statp
->_u
._ext
.nscount6
= nservall
- nserv
;
392 statp
->nsort
= nsort
;
396 if (statp
->defdname
[0] == 0 &&
397 __gethostname(buf
, sizeof(statp
->defdname
) - 1) == 0 &&
398 (cp
= strchr(buf
, '.')) != NULL
)
399 strcpy(statp
->defdname
, cp
+ 1);
401 /* find components of local domain that might be searched */
402 if (havesearch
== 0) {
404 *pp
++ = statp
->defdname
;
409 for (cp
= statp
->defdname
; *cp
; cp
++)
410 dots
+= (*cp
== '.');
412 cp
= statp
->defdname
;
413 while (pp
< statp
->dnsrch
+ MAXDFLSRCH
) {
414 if (dots
< LOCALDOMAINPARTS
)
416 cp
= __rawmemchr(cp
, '.') + 1; /* we know there is one */
422 if (statp
->options
& RES_DEBUG
) {
423 printf(";; res_init()... default dnsrch list:\n");
424 for (pp
= statp
->dnsrch
; *pp
; pp
++)
425 printf(";;\t%s\n", *pp
);
426 printf(";;\t..END..\n");
429 #endif /* !RFC1535 */
432 if ((cp
= getenv("RES_OPTIONS")) != NULL
)
433 res_setoptions(statp
, cp
, "env");
434 statp
->options
|= RES_INIT
;
440 res_setoptions(res_state statp
, const char *options
, const char *source
) {
441 const char *cp
= options
;
445 if (statp
->options
& RES_DEBUG
)
446 printf(";; res_setoptions(\"%s\", \"%s\")...\n",
450 /* skip leading and inner runs of spaces */
451 while (*cp
== ' ' || *cp
== '\t')
453 /* search for and process individual options */
454 if (!strncmp(cp
, "ndots:", sizeof("ndots:") - 1)) {
455 i
= atoi(cp
+ sizeof("ndots:") - 1);
456 if (i
<= RES_MAXNDOTS
)
459 statp
->ndots
= RES_MAXNDOTS
;
461 if (statp
->options
& RES_DEBUG
)
462 printf(";;\tndots=%d\n", statp
->ndots
);
464 } else if (!strncmp(cp
, "timeout:", sizeof("timeout:") - 1)) {
465 i
= atoi(cp
+ sizeof("timeout:") - 1);
466 if (i
<= RES_MAXRETRANS
)
469 statp
->retrans
= RES_MAXRETRANS
;
470 } else if (!strncmp(cp
, "attempts:", sizeof("attempts:") - 1)){
471 i
= atoi(cp
+ sizeof("attempts:") - 1);
472 if (i
<= RES_MAXRETRY
)
475 statp
->retry
= RES_MAXRETRY
;
476 } else if (!strncmp(cp
, "debug", sizeof("debug") - 1)) {
478 if (!(statp
->options
& RES_DEBUG
)) {
479 printf(";; res_setoptions(\"%s\", \"%s\")..\n",
481 statp
->options
|= RES_DEBUG
;
483 printf(";;\tdebug\n");
485 } else if (!strncmp(cp
, "inet6", sizeof("inet6") - 1)) {
486 statp
->options
|= RES_USE_INET6
;
487 } else if (!strncmp(cp
, "rotate", sizeof("rotate") - 1)) {
488 statp
->options
|= RES_ROTATE
;
489 } else if (!strncmp(cp
, "no-check-names",
490 sizeof("no-check-names") - 1)) {
491 statp
->options
|= RES_NOCHECKNAME
;
493 /* XXX - print a warning here? */
495 /* skip to next run of spaces */
496 while (*cp
&& *cp
!= ' ' && *cp
!= '\t')
502 /* XXX - should really support CIDR which means explicit masks always. */
504 net_mask(in
) /* XXX - should really use system's version of this */
507 register u_int32_t i
= ntohl(in
.s_addr
);
510 return (htonl(IN_CLASSA_NET
));
511 else if (IN_CLASSB(i
))
512 return (htonl(IN_CLASSB_NET
));
513 return (htonl(IN_CLASSC_NET
));
521 __gettimeofday(&now
, NULL
);
522 return (0xffff & (now
.tv_sec
^ now
.tv_usec
^ __getpid()));
526 * This routine is for closing the socket if a virtual circuit is used and
527 * the program wants to close it. This provides support for endhostent()
528 * which expects to close the socket.
530 * This routine is not expected to be user visible.
533 res_nclose(res_state statp
) {
536 if (statp
->_vcsock
>= 0) {
537 (void) __close(statp
->_vcsock
);
539 statp
->_flags
&= ~(RES_F_VC
| RES_F_CONN
);
542 for (ns
= 0; ns
< MAXNS
; ns
++)
544 for (ns
= 0; ns
< statp
->_u
._ext
.nscount
; ns
++)
546 if (statp
->_u
._ext
.nsaddrs
[ns
]
547 && statp
->_u
._ext
.nssocks
[ns
] != -1) {
548 (void) __close(statp
->_u
._ext
.nssocks
[ns
]);
549 statp
->_u
._ext
.nssocks
[ns
] = -1;
551 statp
->_u
._ext
.nsinit
= 0;