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
23 static 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__
50 const 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
70 const char * const _res_sectioncodes[] = {
71 "ZONE",
72 "PREREQUISITES",
73 "UPDATE",
74 "ADDITIONAL",
75 };
76 #endif
77
78 #ifndef __BIND_NOSTATIC
79 extern struct __res_state _nres;
80
81 /* Proto. */
82
83 int res_ourserver_p(const res_state, const struct sockaddr *);
84
85 #define res_need_init() ((_nres.options & RES_INIT) == 0U)
86
87 int
res_init(void)88 res_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
150 void
p_query(const u_char * msg)151 p_query(const u_char *msg) {
152 fp_query(msg, stdout);
153 }
154
155 void
fp_query(const u_char * msg,FILE * file)156 fp_query(const u_char *msg, FILE *file) {
157 fp_nquery(msg, PACKETSZ, file);
158 }
159
160 void
fp_nquery(const u_char * msg,int len,FILE * file)161 fp_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
168 int
res_mkquery(int op,const char * dname,int class,int type,const u_char * data,int datalen,const u_char * newrr_in,u_char * buf,int buflen)169 res_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
188 int
res_mkupdate(ns_updrec * rrecp_in,u_char * buf,int buflen)189 res_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
199 int
res_query(const char * name,int class,int type,u_char * answer,int anslen)200 res_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
212 void
res_send_setqhook(res_send_qhook hook)213 res_send_setqhook(res_send_qhook hook) {
214 _nres.qhook = hook;
215 }
216
217 void
res_send_setrhook(res_send_rhook hook)218 res_send_setrhook(res_send_rhook hook) {
219 _nres.rhook = hook;
220 }
221
222 int
res_isourserver(const struct sockaddr_in * inp)223 res_isourserver(const struct sockaddr_in *inp) {
224 return (res_ourserver_p(&_nres, (const struct sockaddr *)(const void *)inp));
225 }
226
227 int
res_send(const u_char * buf,int buflen,u_char * ans,int anssiz)228 res_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
238 int
res_sendsigned(const u_char * buf,int buflen,ns_tsig_key * key,u_char * ans,int anssiz)239 res_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
251 void
res_close(void)252 res_close(void) {
253 res_nclose(&_nres);
254 }
255
256 #ifdef _LIBRESOLV
257 int
res_update(ns_updrec * rrecp_in)258 res_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
268 int
res_search(const char * name,int class,int type,u_char * answer,int anslen)269 res_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
282 int
res_querydomain(const char * name,const char * domain,int class,int type,u_char * answer,int anslen)283 res_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
299 int
res_opt(int a,u_char * b,int c,int d)300 res_opt(int a, u_char *b, int c, int d)
301 {
302 return res_nopt(&_nres, a, b, c, d);
303 }
304
305 const char *
hostalias(const char * name)306 hostalias(const char *name) {
307 return NULL;
308 }
309
310 #ifdef ultrix
311 int
local_hostname_length(const char * hostname)312 local_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