1/*
2 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (c) 1995-1999 by Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18#if defined(LIBC_SCCS) && !defined(lint)
19static const char rcsid[] = "$Id: res_data.c,v 1.7 2008/12/11 09:59:00 marka Exp $";
20#endif /* LIBC_SCCS and not lint */
21#include <sys/cdefs.h>
22__FBSDID("$FreeBSD$");
23
24#include "port_before.h"
25
26#include <sys/types.h>
27#include <sys/param.h>
28#include <sys/socket.h>
29#include <sys/time.h>
30
31#include <netinet/in.h>
32#include <arpa/inet.h>
33#include <arpa/nameser.h>
34
35#include <ctype.h>
36#include <netdb.h>
37#include <resolv.h>
38#include <res_update.h>
39#include <stdio.h>
40#include <stdlib.h>
41#include <string.h>
42#include <unistd.h>
43
44#include "port_after.h"
45
46const char *_res_opcodes[] = {
47	"QUERY",
48	"IQUERY",
49	"CQUERYM",
50	"CQUERYU",	/*%< experimental */
51	"NOTIFY",	/*%< experimental */
52	"UPDATE",
53	"6",
54	"7",
55	"8",
56	"9",
57	"10",
58	"11",
59	"12",
60	"13",
61	"ZONEINIT",
62	"ZONEREF",
63};
64
65#ifdef BIND_UPDATE
66const char *_res_sectioncodes[] = {
67	"ZONE",
68	"PREREQUISITES",
69	"UPDATE",
70	"ADDITIONAL",
71};
72#endif
73
74#ifndef __BIND_NOSTATIC
75
76/* Proto. */
77
78int  res_ourserver_p(const res_state, const struct sockaddr_in *);
79
80__noinline int
81res_init(void) {
82	extern int __res_vinit(res_state, int);
83	res_state statp = &_res;
84
85	/*
86	 * These three fields used to be statically initialized.  This made
87	 * it hard to use this code in a shared library.  It is necessary,
88	 * now that we're doing dynamic initialization here, that we preserve
89	 * the old semantics: if an application modifies one of these three
90	 * fields of _res before res_init() is called, res_init() will not
91	 * alter them.  Of course, if an application is setting them to
92	 * _zero_ before calling res_init(), hoping to override what used
93	 * to be the static default, we can't detect it and unexpected results
94	 * will follow.  Zero for any of these fields would make no sense,
95	 * so one can safely assume that the applications were already getting
96	 * unexpected results.
97	 *
98	 * _res.options is tricky since some apps were known to diddle the bits
99	 * before res_init() was first called. We can't replicate that semantic
100	 * with dynamic initialization (they may have turned bits off that are
101	 * set in RES_DEFAULT).  Our solution is to declare such applications
102	 * "broken".  They could fool us by setting RES_INIT but none do (yet).
103	 */
104	if (!statp->retrans)
105		statp->retrans = RES_TIMEOUT;
106	if (!statp->retry)
107		statp->retry = RES_DFLRETRY;
108	if (!(statp->options & RES_INIT))
109		statp->options = RES_DEFAULT;
110
111	return (__res_vinit(statp, 1));
112}
113
114void
115p_query(const u_char *msg) {
116	fp_query(msg, stdout);
117}
118
119void
120fp_query(const u_char *msg, FILE *file) {
121	fp_nquery(msg, PACKETSZ, file);
122}
123
124void
125fp_nquery(const u_char *msg, int len, FILE *file) {
126	res_state statp = &_res;
127	if ((statp->options & RES_INIT) == 0U && res_init() == -1)
128		return;
129
130	res_pquery(statp, msg, len, file);
131}
132
133int
134res_mkquery(int op,			/*!< opcode of query  */
135	    const char *dname,		/*!< domain name  */
136	    int class, int type,	/*!< class and type of query  */
137	    const u_char *data,		/*!< resource record data  */
138	    int datalen,		/*!< length of data  */
139	    const u_char *newrr_in,	/*!< new rr for modify or append  */
140	    u_char *buf,		/*!< buffer to put query  */
141	    int buflen)			/*!< size of buffer  */
142{
143	res_state statp = &_res;
144	if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
145		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
146		return (-1);
147	}
148	return (res_nmkquery(statp, op, dname, class, type,
149			     data, datalen,
150			     newrr_in, buf, buflen));
151}
152
153int
154res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
155	res_state statp = &_res;
156	if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
157		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
158		return (-1);
159	}
160
161	return (res_nmkupdate(statp, rrecp_in, buf, buflen));
162}
163
164int
165res_query(const char *name,	/*!< domain name  */
166	  int class, int type,	/*!< class and type of query  */
167	  u_char *answer,	/*!< buffer to put answer  */
168	  int anslen)		/*!< size of answer buffer  */
169{
170	res_state statp = &_res;
171	if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
172		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
173		return (-1);
174	}
175	return (res_nquery(statp, name, class, type, answer, anslen));
176}
177
178#ifndef _LIBC
179void
180res_send_setqhook(res_send_qhook hook) {
181	_res.qhook = hook;
182}
183
184void
185res_send_setrhook(res_send_rhook hook) {
186	_res.rhook = hook;
187}
188#endif
189
190int
191res_isourserver(const struct sockaddr_in *inp) {
192	return (res_ourserver_p(&_res, inp));
193}
194
195int
196res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) {
197	res_state statp = &_res;
198	if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
199		/* errno should have been set by res_init() in this case. */
200		return (-1);
201	}
202
203	return (res_nsend(statp, buf, buflen, ans, anssiz));
204}
205
206#ifndef _LIBC
207int
208res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key,
209	       u_char *ans, int anssiz)
210{
211	res_state statp = &_res;
212	if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
213		/* errno should have been set by res_init() in this case. */
214		return (-1);
215	}
216
217	return (res_nsendsigned(statp, buf, buflen, key, ans, anssiz));
218}
219#endif
220
221void
222res_close(void) {
223	res_nclose(&_res);
224}
225
226int
227res_update(ns_updrec *rrecp_in) {
228	res_state statp = &_res;
229	if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
230		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
231		return (-1);
232	}
233
234	return (res_nupdate(statp, rrecp_in, NULL));
235}
236
237int
238res_search(const char *name,	/*!< domain name  */
239	   int class, int type,	/*!< class and type of query  */
240	   u_char *answer,	/*!< buffer to put answer  */
241	   int anslen)		/*!< size of answer  */
242{
243	res_state statp = &_res;
244	if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
245		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
246		return (-1);
247	}
248
249	return (res_nsearch(statp, name, class, type, answer, anslen));
250}
251
252int
253res_querydomain(const char *name,
254		const char *domain,
255		int class, int type,	/*!< class and type of query  */
256		u_char *answer,		/*!< buffer to put answer  */
257		int anslen)		/*!< size of answer  */
258{
259	res_state statp = &_res;
260	if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
261		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
262		return (-1);
263	}
264
265	return (res_nquerydomain(statp, name, domain,
266				 class, type,
267				 answer, anslen));
268}
269
270u_int
271res_randomid(void) {
272	res_state statp = &_res;
273	if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
274		RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
275		return (-1);
276	}
277
278	return (res_nrandomid(statp));
279}
280
281int
282res_opt(int n0, u_char *buf, int buflen, int anslen)
283{
284	return (res_nopt(&_res, n0, buf, buflen, anslen));
285}
286
287const char *
288hostalias(const char *name) {
289	static char abuf[MAXDNAME];
290
291	return (res_hostalias(&_res, name, abuf, sizeof abuf));
292}
293
294#ifdef ultrix
295int
296local_hostname_length(const char *hostname) {
297	int len_host, len_domain;
298	res_state statp;
299
300	statp = &_res;
301	if (!*statp->defdname)
302		res_init();
303	len_host = strlen(hostname);
304	len_domain = strlen(statp->defdname);
305	if (len_host > len_domain &&
306	    !strcasecmp(hostname + len_host - len_domain, statp->defdname) &&
307	    hostname[len_host - len_domain - 1] == '.')
308		return (len_host - len_domain - 1);
309	return (0);
310}
311#endif /*ultrix*/
312
313/*
314 * Weak aliases for applications that use certain private entry points,
315 * and fail to include <resolv.h>.
316 */
317#undef res_init
318__weak_reference(__res_init, res_init);
319#undef p_query
320__weak_reference(__p_query, p_query);
321#undef res_mkquery
322__weak_reference(__res_mkquery, res_mkquery);
323#undef res_query
324__weak_reference(__res_query, res_query);
325#undef res_send
326__weak_reference(__res_send, res_send);
327#undef res_close
328__weak_reference(__res_close, _res_close);
329#undef res_search
330__weak_reference(__res_search, res_search);
331#undef res_querydomain
332__weak_reference(__res_querydomain, res_querydomain);
333
334#endif
335
336/*! \file */
337