1/*	$NetBSD: res_data.c,v 1.8 2004/06/09 18:07:03 christos Exp $	*/
2
3/*
4 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
5 * Copyright (c) 1995-1999 by Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
17 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20#include <sys/cdefs.h>
21#if defined(LIBC_SCCS) && !defined(lint)
22#ifdef notdef
23static const char rcsid[] = "Id: res_data.c,v 1.1.206.2 2004/03/16 12:34:18 marka Exp";
24#else
25__RCSID("$NetBSD: res_data.c,v 1.8 2004/06/09 18:07:03 christos Exp $");
26#endif
27#endif /* LIBC_SCCS and not lint */
28
29
30
31#include <sys/types.h>
32#include <sys/param.h>
33#include <sys/socket.h>
34#include <sys/time.h>
35
36#include <netinet/in.h>
37#include <arpa/inet.h>
38#include "arpa_nameser.h"
39
40#include <ctype.h>
41#include <netdb.h>
42#include "resolv_private.h"
43#include <stdio.h>
44#include <stdlib.h>
45#include <string.h>
46#include <unistd.h>
47
48
49__LIBC_HIDDEN__
50const char * const _res_opcodes[] = {
51	"QUERY",
52	"IQUERY",
53	"CQUERYM",
54	"CQUERYU",	/* experimental */
55	"NOTIFY",	/* experimental */
56	"UPDATE",
57	"6",
58	"7",
59	"8",
60	"9",
61	"10",
62	"11",
63	"12",
64	"13",
65	"ZONEINIT",
66	"ZONEREF",
67};
68
69#ifdef BIND_UPDATE
70const char * const _res_sectioncodes[] = {
71	"ZONE",
72	"PREREQUISITES",
73	"UPDATE",
74	"ADDITIONAL",
75};
76#endif
77
78#ifndef __BIND_NOSTATIC
79extern struct __res_state _nres;
80
81/* Proto. */
82
83int  res_ourserver_p(const res_state, const struct sockaddr *);
84
85#define res_need_init()   ((_nres.options & RES_INIT) == 0U)
86
87int
88res_init(void) {
89	int rv;
90	extern int __res_vinit(res_state, int);
91#ifdef COMPAT__RES
92	/*
93	 * Compatibility with program that were accessing _res directly
94	 * to set options. We keep another struct res that is the same
95	 * size as the original res structure, and then copy fields to
96	 * it so that we achieve the same initialization
97	 */
98	extern void *__res_get_old_state(void);
99	extern void __res_put_old_state(void *);
100	res_state ores = __res_get_old_state();
101
102	if (ores->options != 0)
103		_nres.options = ores->options;
104	if (ores->retrans != 0)
105		_nres.retrans = ores->retrans;
106	if (ores->retry != 0)
107		_nres.retry = ores->retry;
108#endif
109
110	/*
111	 * These three fields used to be statically initialized.  This made
112	 * it hard to use this code in a shared library.  It is necessary,
113	 * now that we're doing dynamic initialization here, that we preserve
114	 * the old semantics: if an application modifies one of these three
115	 * fields of _res before res_init() is called, res_init() will not
116	 * alter them.  Of course, if an application is setting them to
117	 * _zero_ before calling res_init(), hoping to override what used
118	 * to be the static default, we can't detect it and unexpected results
119	 * will follow.  Zero for any of these fields would make no sense,
120	 * so one can safely assume that the applications were already getting
121	 * unexpected results.
122	 *
123	 * _nres.options is tricky since some apps were known to diddle the bits
124	 * before res_init() was first called. We can't replicate that semantic
125	 * with dynamic initialization (they may have turned bits off that are
126	 * set in RES_DEFAULT).  Our solution is to declare such applications
127	 * "broken".  They could fool us by setting RES_INIT but none do (yet).
128	 */
129	if (!_nres.retrans)
130		_nres.retrans = RES_TIMEOUT;
131	if (!_nres.retry)
132		_nres.retry = 4;
133	if (!(_nres.options & RES_INIT))
134		_nres.options = RES_DEFAULT;
135
136	/*
137	 * This one used to initialize implicitly to zero, so unless the app
138	 * has set it to something in particular, we can randomize it now.
139	 */
140	if (!_nres.id)
141		_nres.id = res_randomid();
142
143	rv = __res_vinit(&_nres, 1);
144#ifdef COMPAT__RES
145	__res_put_old_state(&_nres);
146#endif
147	return rv;
148}
149
150void
151p_query(const u_char *msg) {
152	fp_query(msg, stdout);
153}
154
155void
156fp_query(const u_char *msg, FILE *file) {
157	fp_nquery(msg, PACKETSZ, file);
158}
159
160void
161fp_nquery(const u_char *msg, int len, FILE *file) {
162	if (res_need_init() && res_init() == -1)
163		return;
164
165	res_pquery(&_nres, msg, len, file);
166}
167
168int
169res_mkquery(int op,			/* opcode of query */
170	    const char *dname,		/* domain name */
171	    int class, int type,	/* class and type of query */
172	    const u_char *data,		/* resource record data */
173	    int datalen,		/* length of data */
174	    const u_char *newrr_in,	/* new rr for modify or append */
175	    u_char *buf,		/* buffer to put query */
176	    int buflen)			/* size of buffer */
177{
178	if (res_need_init() && res_init() == -1) {
179		RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
180		return (-1);
181	}
182	return (res_nmkquery(&_nres, op, dname, class, type,
183			     data, datalen,
184			     newrr_in, buf, buflen));
185}
186
187#ifdef _LIBRESOLV
188int
189res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
190	if (res_need_init() && res_init() == -1) {
191		RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
192		return (-1);
193	}
194
195	return (res_nmkupdate(&_nres, rrecp_in, buf, buflen));
196}
197#endif
198
199int
200res_query(const char *name,	/* domain name */
201	  int class, int type,	/* class and type of query */
202	  u_char *answer,	/* buffer to put answer */
203	  int anslen)		/* size of answer buffer */
204{
205	if (res_need_init() && res_init() == -1) {
206		RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
207		return (-1);
208	}
209	return (res_nquery(&_nres, name, class, type, answer, anslen));
210}
211
212void
213res_send_setqhook(res_send_qhook hook) {
214	_nres.qhook = hook;
215}
216
217void
218res_send_setrhook(res_send_rhook hook) {
219	_nres.rhook = hook;
220}
221
222int
223res_isourserver(const struct sockaddr_in *inp) {
224	return (res_ourserver_p(&_nres, (const struct sockaddr *)(const void *)inp));
225}
226
227int
228res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) {
229	if (res_need_init() && res_init() == -1) {
230		/* errno should have been set by res_init() in this case. */
231		return (-1);
232	}
233
234	return (res_nsend(&_nres, buf, buflen, ans, anssiz));
235}
236
237#ifdef _LIBRESOLV
238int
239res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key,
240	       u_char *ans, int anssiz)
241{
242	if (res_need_init() && res_init() == -1) {
243		/* errno should have been set by res_init() in this case. */
244		return (-1);
245	}
246
247	return (res_nsendsigned(&_nres, buf, buflen, key, ans, anssiz));
248}
249#endif
250
251void
252res_close(void) {
253	res_nclose(&_nres);
254}
255
256#ifdef _LIBRESOLV
257int
258res_update(ns_updrec *rrecp_in) {
259	if (res_need_init() && res_init() == -1) {
260		RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
261		return (-1);
262	}
263
264	return (res_nupdate(&_nres, rrecp_in, NULL));
265}
266#endif
267
268int
269res_search(const char *name,	/* domain name */
270	   int class, int type,	/* class and type of query */
271	   u_char *answer,	/* buffer to put answer */
272	   int anslen)		/* size of answer */
273{
274	if (res_need_init() && res_init() == -1) {
275		RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
276		return (-1);
277	}
278
279	return (res_nsearch(&_nres, name, class, type, answer, anslen));
280}
281
282int
283res_querydomain(const char *name,
284		const char *domain,
285		int class, int type,	/* class and type of query */
286		u_char *answer,		/* buffer to put answer */
287		int anslen)		/* size of answer */
288{
289	if (res_need_init() && res_init() == -1) {
290		RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
291		return (-1);
292	}
293
294	return (res_nquerydomain(&_nres, name, domain,
295				 class, type,
296				 answer, anslen));
297}
298
299int
300res_opt(int a, u_char *b, int c, int d)
301{
302	return res_nopt(&_nres, a, b, c, d);
303}
304
305const char *
306hostalias(const char *name) {
307	return NULL;
308}
309
310#ifdef ultrix
311int
312local_hostname_length(const char *hostname) {
313	int len_host, len_domain;
314
315	if (!*_nres.defdname)
316		res_init();
317	len_host = strlen(hostname);
318	len_domain = strlen(_nres.defdname);
319	if (len_host > len_domain &&
320	    !strcasecmp(hostname + len_host - len_domain, _nres.defdname) &&
321	    hostname[len_host - len_domain - 1] == '.')
322		return (len_host - len_domain - 1);
323	return (0);
324}
325#endif /*ultrix*/
326
327#endif
328