about summary refs log tree commit diff
path: root/resolv/res_data.c
blob: 438f815605d95a282dbd5fbff60e2a047867310e (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
/*
 * Copyright (c) 1995-1999 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static const char rcsid[] = "$BINDId: res_data.c,v 8.17 1999/10/13 17:11:31 vixie Exp $";
#endif /* LIBC_SCCS and not lint */

#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>

#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>

#include <ctype.h>
#include <netdb.h>
#include <resolv.h>
#ifdef BIND_UPDATE
#include <res_update.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

const char *_res_opcodes[] attribute_hidden = {
	"QUERY",
	"IQUERY",
	"CQUERYM",
	"CQUERYU",	/* experimental */
	"NOTIFY",	/* experimental */
	"UPDATE",
	"6",
	"7",
	"8",
	"9",
	"10",
	"11",
	"12",
	"13",
	"ZONEINIT",
	"ZONEREF",
};

#ifdef BIND_UPDATE
const char *_res_sectioncodes[] attribute_hidden = {
	"ZONE",
	"PREREQUISITES",
	"UPDATE",
	"ADDITIONAL",
};
#endif

#ifndef __BIND_NOSTATIC
#ifdef _LIBC
/* The definition has been moved to res_libc.c.  */
#else
#undef _res
struct __res_state _res
# if defined(__BIND_RES_TEXT)
	= { RES_TIMEOUT, }	/* Motorola, et al. */
# endif
        ;
#endif

/* Proto. */
#ifndef _LIBC
int  res_ourserver_p(const res_state, const struct sockaddr_in *);
void res_pquery(const res_state, const u_char *, int, FILE *);
#endif

#ifndef _LIBC
/* Moved to res_libc.c since res_init() should go into libc.so but the
   rest of this file not.  */
int
res_init(void) {
	extern int __res_vinit(res_state, int);

	/*
	 * These three fields used to be statically initialized.  This made
	 * it hard to use this code in a shared library.  It is necessary,
	 * now that we're doing dynamic initialization here, that we preserve
	 * the old semantics: if an application modifies one of these three
	 * fields of _res before res_init() is called, res_init() will not
	 * alter them.  Of course, if an application is setting them to
	 * _zero_ before calling res_init(), hoping to override what used
	 * to be the static default, we can't detect it and unexpected results
	 * will follow.  Zero for any of these fields would make no sense,
	 * so one can safely assume that the applications were already getting
	 * unexpected results.
	 *
	 * _res.options is tricky since some apps were known to diddle the bits
	 * before res_init() was first called. We can't replicate that semantic
	 * with dynamic initialization (they may have turned bits off that are
	 * set in RES_DEFAULT).  Our solution is to declare such applications
	 * "broken".  They could fool us by setting RES_INIT but none do (yet).
	 */
	if (!_res.retrans)
		_res.retrans = RES_TIMEOUT;
	if (!_res.retry)
		_res.retry = 4;
	if (!(_res.options & RES_INIT))
		_res.options = RES_DEFAULT;

	/*
	 * This one used to initialize implicitly to zero, so unless the app
	 * has set it to something in particular, we can randomize it now.
	 */
	if (!_res.id)
		_res.id = res_randomid();

	return (__res_vinit(&_res, 1));
}
#endif

void
p_query(const u_char *msg) {
	fp_query(msg, stdout);
}

void
fp_query(const u_char *msg, FILE *file) {
	fp_nquery(msg, PACKETSZ, file);
}
libresolv_hidden_def (fp_query)

void
fp_nquery(const u_char *msg, int len, FILE *file) {
	if (__res_maybe_init (&_res, 0) == -1)
		return;

	res_pquery(&_res, msg, len, file);
}
libresolv_hidden_def (fp_nquery)

int
res_mkquery(int op,			/* opcode of query */
	    const char *dname,		/* domain name */
	    int class, int type,	/* class and type of query */
	    const u_char *data,		/* resource record data */
	    int datalen,		/* length of data */
	    const u_char *newrr_in,	/* new rr for modify or append */
	    u_char *buf,		/* buffer to put query */
	    int buflen)			/* size of buffer */
{
	if (__res_maybe_init (&_res, 1) == -1) {
		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
		return (-1);
	}
	return (res_nmkquery(&_res, op, dname, class, type,
			     data, datalen,
			     newrr_in, buf, buflen));
}

#ifdef BIND_UPDATE
int
res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
	if (__res_maybe_init (&_res, 1) == -1) {
		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
		return (-1);
	}

	return (res_nmkupdate(&_res, rrecp_in, buf, buflen));
}
#endif

int
res_query(const char *name,	/* domain name */
	  int class, int type,	/* class and type of query */
	  u_char *answer,	/* buffer to put answer */
	  int anslen)		/* size of answer buffer */
{
	if (__res_maybe_init (&_res, 1) == -1) {
		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
		return (-1);
	}
	return (res_nquery(&_res, name, class, type, answer, anslen));
}

void
res_send_setqhook(res_send_qhook hook) {
	_res.qhook = hook;
}

void
res_send_setrhook(res_send_rhook hook) {
	_res.rhook = hook;
}

int
res_isourserver(const struct sockaddr_in *inp) {
	return (res_ourserver_p(&_res, (const struct sockaddr_in6 *) inp));
}

int
res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) {
	if (__res_maybe_init (&_res, 1) == -1) {
		/* errno should have been set by res_init() in this case. */
		return (-1);
	}

	return (res_nsend(&_res, buf, buflen, ans, anssiz));
}

#ifndef _LIBC
int
res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key,
	       u_char *ans, int anssiz)
{
	if (__res_maybe_init (&_res, 1) == -1) {
		/* errno should have been set by res_init() in this case. */
		return (-1);
	}

	return (res_nsendsigned(&_res, buf, buflen, key, ans, anssiz));
}
#endif

void
res_close(void) {
#ifdef _LIBC
  	/*
	 * Some stupid programs out there call res_close() before res_init().
	 * Since _res._vcsock isn't explicitly initialized, these means that
	 * we could do a close(0), which might lead to some security problems.
	 * Therefore we check if res_init() was called before by looking at
	 * the RES_INIT bit in _res.options.  If it hasn't been set we bail out
	 * early.  */
	if ((_res.options & RES_INIT) == 0)
	  return;
#endif
	res_nclose(&_res);
}

#ifdef BIND_UPDATE
int
res_update(ns_updrec *rrecp_in) {
	if (__res_maybe_init (&_res, 1) == -1) {
		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
		return (-1);
	}

	return (res_nupdate(&_res, rrecp_in, NULL));
}
#endif

int
res_search(const char *name,	/* domain name */
	   int class, int type,	/* class and type of query */
	   u_char *answer,	/* buffer to put answer */
	   int anslen)		/* size of answer */
{
	if (__res_maybe_init (&_res, 1) == -1) {
		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
		return (-1);
	}

	return (res_nsearch(&_res, name, class, type, answer, anslen));
}

int
res_querydomain(const char *name,
		const char *domain,
		int class, int type,	/* class and type of query */
		u_char *answer,		/* buffer to put answer */
		int anslen)		/* size of answer */
{
	if (__res_maybe_init (&_res, 1) == -1) {
		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
		return (-1);
	}

	return (res_nquerydomain(&_res, name, domain,
				 class, type,
				 answer, anslen));
}

const char *
hostalias(const char *name) {
	static char abuf[MAXDNAME];

	return (res_hostalias(&_res, name, abuf, sizeof abuf));
}
libresolv_hidden_def (hostalias)

#ifdef ultrix
int
local_hostname_length(const char *hostname) {
	int len_host, len_domain;

	if (!*_res.defdname)
		res_init();
	len_host = strlen(hostname);
	len_domain = strlen(_res.defdname);
	if (len_host > len_domain &&
	    !strcasecmp(hostname + len_host - len_domain, _res.defdname) &&
	    hostname[len_host - len_domain - 1] == '.')
		return (len_host - len_domain - 1);
	return (0);
}
#endif /*ultrix*/

#endif


#include <shlib-compat.h>

#if SHLIB_COMPAT(libresolv, GLIBC_2_0, GLIBC_2_2)
# undef res_mkquery
# undef res_query
# undef res_querydomain
# undef res_search
weak_alias (__res_mkquery, res_mkquery);
weak_alias (__res_query, res_query);
weak_alias (__res_querydomain, res_querydomain);
weak_alias (__res_search, res_search);
#endif