1 /*	$NetBSD: res_data.c,v 1.1.1.1 2009/04/12 15:33:57 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 #if defined(LIBC_SCCS) && !defined(lint)
21 static const char rcsid[] = "Id: res_data.c,v 1.7 2008/12/11 09:59:00 marka Exp";
22 #endif /* LIBC_SCCS and not lint */
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 
46 const 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
66 const char *_res_sectioncodes[] = {
67 	"ZONE",
68 	"PREREQUISITES",
69 	"UPDATE",
70 	"ADDITIONAL",
71 };
72 #endif
73 
74 #undef _res
75 #ifndef __BIND_NOSTATIC
76 struct __res_state _res
77 # if defined(__BIND_RES_TEXT)
78 	= { RES_TIMEOUT, }	/*%< Motorola, et al. */
79 # endif
80         ;
81 
82 #if defined(DO_PTHREADS) || defined(__linux)
83 #define _res (*__res_state())
84 #endif
85 
86 /* Proto. */
87 
88 int  res_ourserver_p(const res_state, const struct sockaddr_in *);
89 
90 int
91 res_init(void) {
92 	extern int __res_vinit(res_state, int);
93 
94 	/*
95 	 * These three fields used to be statically initialized.  This made
96 	 * it hard to use this code in a shared library.  It is necessary,
97 	 * now that we're doing dynamic initialization here, that we preserve
98 	 * the old semantics: if an application modifies one of these three
99 	 * fields of _res before res_init() is called, res_init() will not
100 	 * alter them.  Of course, if an application is setting them to
101 	 * _zero_ before calling res_init(), hoping to override what used
102 	 * to be the static default, we can't detect it and unexpected results
103 	 * will follow.  Zero for any of these fields would make no sense,
104 	 * so one can safely assume that the applications were already getting
105 	 * unexpected results.
106 	 *
107 	 * _res.options is tricky since some apps were known to diddle the bits
108 	 * before res_init() was first called. We can't replicate that semantic
109 	 * with dynamic initialization (they may have turned bits off that are
110 	 * set in RES_DEFAULT).  Our solution is to declare such applications
111 	 * "broken".  They could fool us by setting RES_INIT but none do (yet).
112 	 */
113 	if (!_res.retrans)
114 		_res.retrans = RES_TIMEOUT;
115 	if (!_res.retry)
116 		_res.retry = 4;
117 	if (!(_res.options & RES_INIT))
118 		_res.options = RES_DEFAULT;
119 
120 	/*
121 	 * This one used to initialize implicitly to zero, so unless the app
122 	 * has set it to something in particular, we can randomize it now.
123 	 */
124 	if (!_res.id)
125 		_res.id = res_nrandomid(&_res);
126 
127 	return (__res_vinit(&_res, 1));
128 }
129 
130 void
131 p_query(const u_char *msg) {
132 	fp_query(msg, stdout);
133 }
134 
135 void
136 fp_query(const u_char *msg, FILE *file) {
137 	fp_nquery(msg, PACKETSZ, file);
138 }
139 
140 void
141 fp_nquery(const u_char *msg, int len, FILE *file) {
142 	if ((_res.options & RES_INIT) == 0U && res_init() == -1)
143 		return;
144 
145 	res_pquery(&_res, msg, len, file);
146 }
147 
148 int
149 res_mkquery(int op,			/*!< opcode of query  */
150 	    const char *dname,		/*!< domain name  */
151 	    int class, int type,	/*!< class and type of query  */
152 	    const u_char *data,		/*!< resource record data  */
153 	    int datalen,		/*!< length of data  */
154 	    const u_char *newrr_in,	/*!< new rr for modify or append  */
155 	    u_char *buf,		/*!< buffer to put query  */
156 	    int buflen)			/*!< size of buffer  */
157 {
158 	if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
159 		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
160 		return (-1);
161 	}
162 	return (res_nmkquery(&_res, op, dname, class, type,
163 			     data, datalen,
164 			     newrr_in, buf, buflen));
165 }
166 
167 int
168 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
169 	if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
170 		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
171 		return (-1);
172 	}
173 
174 	return (res_nmkupdate(&_res, rrecp_in, buf, buflen));
175 }
176 
177 int
178 res_query(const char *name,	/*!< domain name  */
179 	  int class, int type,	/*!< class and type of query  */
180 	  u_char *answer,	/*!< buffer to put answer  */
181 	  int anslen)		/*!< size of answer buffer  */
182 {
183 	if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
184 		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
185 		return (-1);
186 	}
187 	return (res_nquery(&_res, name, class, type, answer, anslen));
188 }
189 
190 void
191 res_send_setqhook(res_send_qhook hook) {
192 	_res.qhook = hook;
193 }
194 
195 void
196 res_send_setrhook(res_send_rhook hook) {
197 	_res.rhook = hook;
198 }
199 
200 int
201 res_isourserver(const struct sockaddr_in *inp) {
202 	return (res_ourserver_p(&_res, inp));
203 }
204 
205 int
206 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) {
207 	if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
208 		/* errno should have been set by res_init() in this case. */
209 		return (-1);
210 	}
211 
212 	return (res_nsend(&_res, buf, buflen, ans, anssiz));
213 }
214 
215 int
216 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key,
217 	       u_char *ans, int anssiz)
218 {
219 	if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
220 		/* errno should have been set by res_init() in this case. */
221 		return (-1);
222 	}
223 
224 	return (res_nsendsigned(&_res, buf, buflen, key, ans, anssiz));
225 }
226 
227 void
228 res_close(void) {
229 	res_nclose(&_res);
230 }
231 
232 int
233 res_update(ns_updrec *rrecp_in) {
234 	if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
235 		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
236 		return (-1);
237 	}
238 
239 	return (res_nupdate(&_res, rrecp_in, NULL));
240 }
241 
242 int
243 res_search(const char *name,	/*!< domain name  */
244 	   int class, int type,	/*!< class and type of query  */
245 	   u_char *answer,	/*!< buffer to put answer  */
246 	   int anslen)		/*!< size of answer  */
247 {
248 	if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
249 		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
250 		return (-1);
251 	}
252 
253 	return (res_nsearch(&_res, name, class, type, answer, anslen));
254 }
255 
256 int
257 res_querydomain(const char *name,
258 		const char *domain,
259 		int class, int type,	/*!< class and type of query  */
260 		u_char *answer,		/*!< buffer to put answer  */
261 		int anslen)		/*!< size of answer  */
262 {
263 	if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
264 		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
265 		return (-1);
266 	}
267 
268 	return (res_nquerydomain(&_res, name, domain,
269 				 class, type,
270 				 answer, anslen));
271 }
272 
273 u_int
274 res_randomid(void) {
275 	if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
276 		RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
277 		return (-1);
278 	}
279 
280 	return (res_nrandomid(&_res));
281 }
282 
283 const char *
284 hostalias(const char *name) {
285 	static char abuf[MAXDNAME];
286 
287 	return (res_hostalias(&_res, name, abuf, sizeof abuf));
288 }
289 
290 #ifdef ultrix
291 int
292 local_hostname_length(const char *hostname) {
293 	int len_host, len_domain;
294 
295 	if (!*_res.defdname)
296 		res_init();
297 	len_host = strlen(hostname);
298 	len_domain = strlen(_res.defdname);
299 	if (len_host > len_domain &&
300 	    !strcasecmp(hostname + len_host - len_domain, _res.defdname) &&
301 	    hostname[len_host - len_domain - 1] == '.')
302 		return (len_host - len_domain - 1);
303 	return (0);
304 }
305 #endif /*ultrix*/
306 
307 #endif
308 
309 /*! \file */
310