1 /*-
2 * SPDX-License-Identifier: ISC
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 #include "port_before.h"
24
25 #include <sys/param.h>
26 #include <sys/socket.h>
27 #include <sys/time.h>
28
29 #include <netinet/in.h>
30 #include <arpa/inet.h>
31 #include <arpa/nameser.h>
32
33 #include <ctype.h>
34 #include <netdb.h>
35 #include <resolv.h>
36 #include <res_update.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <unistd.h>
41
42 #include "port_after.h"
43
44 const char *_res_opcodes[] = {
45 "QUERY",
46 "IQUERY",
47 "CQUERYM",
48 "CQUERYU", /*%< experimental */
49 "NOTIFY", /*%< experimental */
50 "UPDATE",
51 "6",
52 "7",
53 "8",
54 "9",
55 "10",
56 "11",
57 "12",
58 "13",
59 "ZONEINIT",
60 "ZONEREF",
61 };
62
63 #ifdef BIND_UPDATE
64 const char *_res_sectioncodes[] = {
65 "ZONE",
66 "PREREQUISITES",
67 "UPDATE",
68 "ADDITIONAL",
69 };
70 #endif
71
72 #ifndef __BIND_NOSTATIC
73
74 /* Proto. */
75
76 int res_ourserver_p(const res_state, const struct sockaddr_in *);
77
78 __noinline int
res_init(void)79 res_init(void) {
80 extern int __res_vinit(res_state, int);
81 res_state statp = &_res;
82
83 /*
84 * These three fields used to be statically initialized. This made
85 * it hard to use this code in a shared library. It is necessary,
86 * now that we're doing dynamic initialization here, that we preserve
87 * the old semantics: if an application modifies one of these three
88 * fields of _res before res_init() is called, res_init() will not
89 * alter them. Of course, if an application is setting them to
90 * _zero_ before calling res_init(), hoping to override what used
91 * to be the static default, we can't detect it and unexpected results
92 * will follow. Zero for any of these fields would make no sense,
93 * so one can safely assume that the applications were already getting
94 * unexpected results.
95 *
96 * _res.options is tricky since some apps were known to diddle the bits
97 * before res_init() was first called. We can't replicate that semantic
98 * with dynamic initialization (they may have turned bits off that are
99 * set in RES_DEFAULT). Our solution is to declare such applications
100 * "broken". They could fool us by setting RES_INIT but none do (yet).
101 */
102 if (!statp->retrans)
103 statp->retrans = RES_TIMEOUT;
104 if (!statp->retry)
105 statp->retry = RES_DFLRETRY;
106 if (!(statp->options & RES_INIT))
107 statp->options = RES_DEFAULT;
108
109 return (__res_vinit(statp, 1));
110 }
111
112 void
p_query(const u_char * msg)113 p_query(const u_char *msg) {
114 fp_query(msg, stdout);
115 }
116
117 void
fp_query(const u_char * msg,FILE * file)118 fp_query(const u_char *msg, FILE *file) {
119 fp_nquery(msg, PACKETSZ, file);
120 }
121
122 void
fp_nquery(const u_char * msg,int len,FILE * file)123 fp_nquery(const u_char *msg, int len, FILE *file) {
124 res_state statp = &_res;
125 if ((statp->options & RES_INIT) == 0U && res_init() == -1)
126 return;
127
128 res_pquery(statp, msg, len, file);
129 }
130
131 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)132 res_mkquery(int op, /*!< opcode of query */
133 const char *dname, /*!< domain name */
134 int class, int type, /*!< class and type of query */
135 const u_char *data, /*!< resource record data */
136 int datalen, /*!< length of data */
137 const u_char *newrr_in, /*!< new rr for modify or append */
138 u_char *buf, /*!< buffer to put query */
139 int buflen) /*!< size of buffer */
140 {
141 res_state statp = &_res;
142 if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
143 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
144 return (-1);
145 }
146 return (res_nmkquery(statp, op, dname, class, type,
147 data, datalen,
148 newrr_in, buf, buflen));
149 }
150
151 int
res_mkupdate(ns_updrec * rrecp_in,u_char * buf,int buflen)152 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
153 res_state statp = &_res;
154 if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
155 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
156 return (-1);
157 }
158
159 return (res_nmkupdate(statp, rrecp_in, buf, buflen));
160 }
161
162 int
res_query(const char * name,int class,int type,u_char * answer,int anslen)163 res_query(const char *name, /*!< domain name */
164 int class, int type, /*!< class and type of query */
165 u_char *answer, /*!< buffer to put answer */
166 int anslen) /*!< size of answer buffer */
167 {
168 res_state statp = &_res;
169 if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
170 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
171 return (-1);
172 }
173 return (res_nquery(statp, name, class, type, answer, anslen));
174 }
175
176 #ifndef _LIBC
177 void
res_send_setqhook(res_send_qhook hook)178 res_send_setqhook(res_send_qhook hook) {
179 _res.qhook = hook;
180 }
181
182 void
res_send_setrhook(res_send_rhook hook)183 res_send_setrhook(res_send_rhook hook) {
184 _res.rhook = hook;
185 }
186 #endif
187
188 int
res_isourserver(const struct sockaddr_in * inp)189 res_isourserver(const struct sockaddr_in *inp) {
190 return (res_ourserver_p(&_res, inp));
191 }
192
193 int
res_send(const u_char * buf,int buflen,u_char * ans,int anssiz)194 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) {
195 res_state statp = &_res;
196 if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
197 /* errno should have been set by res_init() in this case. */
198 return (-1);
199 }
200
201 return (res_nsend(statp, buf, buflen, ans, anssiz));
202 }
203
204 #ifndef _LIBC
205 int
res_sendsigned(const u_char * buf,int buflen,ns_tsig_key * key,u_char * ans,int anssiz)206 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key,
207 u_char *ans, int anssiz)
208 {
209 res_state statp = &_res;
210 if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
211 /* errno should have been set by res_init() in this case. */
212 return (-1);
213 }
214
215 return (res_nsendsigned(statp, buf, buflen, key, ans, anssiz));
216 }
217 #endif
218
219 void
res_close(void)220 res_close(void) {
221 res_nclose(&_res);
222 }
223
224 int
res_update(ns_updrec * rrecp_in)225 res_update(ns_updrec *rrecp_in) {
226 res_state statp = &_res;
227 if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
228 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
229 return (-1);
230 }
231
232 return (res_nupdate(statp, rrecp_in, NULL));
233 }
234
235 int
res_search(const char * name,int class,int type,u_char * answer,int anslen)236 res_search(const char *name, /*!< domain name */
237 int class, int type, /*!< class and type of query */
238 u_char *answer, /*!< buffer to put answer */
239 int anslen) /*!< size of answer */
240 {
241 res_state statp = &_res;
242 if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
243 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
244 return (-1);
245 }
246
247 return (res_nsearch(statp, name, class, type, answer, anslen));
248 }
249
250 int
res_querydomain(const char * name,const char * domain,int class,int type,u_char * answer,int anslen)251 res_querydomain(const char *name,
252 const char *domain,
253 int class, int type, /*!< class and type of query */
254 u_char *answer, /*!< buffer to put answer */
255 int anslen) /*!< size of answer */
256 {
257 res_state statp = &_res;
258 if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
259 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
260 return (-1);
261 }
262
263 return (res_nquerydomain(statp, name, domain,
264 class, type,
265 answer, anslen));
266 }
267
268 u_int
res_randomid(void)269 res_randomid(void) {
270 res_state statp = &_res;
271 if ((statp->options & RES_INIT) == 0U && res_init() == -1) {
272 RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
273 return (-1);
274 }
275
276 return (res_nrandomid(statp));
277 }
278
279 int
res_opt(int n0,u_char * buf,int buflen,int anslen)280 res_opt(int n0, u_char *buf, int buflen, int anslen)
281 {
282 return (res_nopt(&_res, n0, buf, buflen, anslen));
283 }
284
285 const char *
hostalias(const char * name)286 hostalias(const char *name) {
287 static char abuf[MAXDNAME];
288
289 return (res_hostalias(&_res, name, abuf, sizeof abuf));
290 }
291
292 #ifdef ultrix
293 int
local_hostname_length(const char * hostname)294 local_hostname_length(const char *hostname) {
295 int len_host, len_domain;
296 res_state statp;
297
298 statp = &_res;
299 if (!*statp->defdname)
300 res_init();
301 len_host = strlen(hostname);
302 len_domain = strlen(statp->defdname);
303 if (len_host > len_domain &&
304 !strcasecmp(hostname + len_host - len_domain, statp->defdname) &&
305 hostname[len_host - len_domain - 1] == '.')
306 return (len_host - len_domain - 1);
307 return (0);
308 }
309 #endif /*ultrix*/
310
311 /*
312 * Weak aliases for applications that use certain private entry points,
313 * and fail to include <resolv.h>.
314 */
315 #undef res_init
316 __weak_reference(__res_init, res_init);
317 #undef p_query
318 __weak_reference(__p_query, p_query);
319 #undef res_mkquery
320 __weak_reference(__res_mkquery, res_mkquery);
321 #undef res_query
322 __weak_reference(__res_query, res_query);
323 #undef res_send
324 __weak_reference(__res_send, res_send);
325 #undef res_close
326 __weak_reference(__res_close, _res_close);
327 #undef res_search
328 __weak_reference(__res_search, res_search);
329 #undef res_querydomain
330 __weak_reference(__res_querydomain, res_querydomain);
331
332 #endif
333
334 /*! \file */
335