res_data.c revision 1.9
1 /* $NetBSD: res_data.c,v 1.9 2007/01/27 22:26:44 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 1.3.18.1 2005/04/27 05:01:10 sra Exp"; 24 #else 25 __RCSID("$NetBSD: res_data.c,v 1.9 2007/01/27 22:26:44 christos Exp $"); 26 #endif 27 #endif /* LIBC_SCCS and not lint */ 28 29 #include "port_before.h" 30 31 #include "namespace.h" 32 #include <sys/types.h> 33 #include <sys/param.h> 34 #include <sys/socket.h> 35 #include <sys/time.h> 36 37 #include <netinet/in.h> 38 #include <arpa/inet.h> 39 #include <arpa/nameser.h> 40 41 #include <ctype.h> 42 #include <netdb.h> 43 #include <resolv.h> 44 #include <res_update.h> 45 #include <stdio.h> 46 #include <stdlib.h> 47 #include <string.h> 48 #include <unistd.h> 49 50 #include "port_after.h" 51 52 #ifdef __weak_alias 53 __weak_alias(res_init,_res_init) 54 __weak_alias(res_mkquery,_res_mkquery) 55 __weak_alias(res_query,_res_query) 56 __weak_alias(res_search,_res_search) 57 __weak_alias(res_send,__res_send) 58 __weak_alias(res_close,__res_close) 59 /* XXX: these leaked in the old bind8 libc */ 60 __weak_alias(res_querydomain,__res_querydomain) 61 __weak_alias(res_send_setqhook,__res_send_setqhook) 62 __weak_alias(res_send_setrhook,__res_send_setrhook) 63 #if 0 64 __weak_alias(p_query,__p_query) 65 __weak_alias(fp_query,__fp_query) 66 __weak_alias(fp_nquery,__fp_nquery) 67 __weak_alias(res_isourserver,__res_isourserver) 68 __weak_alias(res_opt,_res_opt) 69 __weak_alias(hostalias,__hostalias) 70 #endif 71 #endif 72 73 const char *_res_opcodes[] = { 74 "QUERY", 75 "IQUERY", 76 "CQUERYM", 77 "CQUERYU", /*%< experimental */ 78 "NOTIFY", /*%< experimental */ 79 "UPDATE", 80 "6", 81 "7", 82 "8", 83 "9", 84 "10", 85 "11", 86 "12", 87 "13", 88 "ZONEINIT", 89 "ZONEREF", 90 }; 91 92 #ifdef BIND_UPDATE 93 const char *_res_sectioncodes[] = { 94 "ZONE", 95 "PREREQUISITES", 96 "UPDATE", 97 "ADDITIONAL", 98 }; 99 #endif 100 101 #ifndef __BIND_NOSTATIC 102 extern struct __res_state _nres; 103 104 /* Proto. */ 105 106 int res_ourserver_p(const res_state, const struct sockaddr *); 107 108 int 109 res_init(void) { 110 int rv; 111 extern int __res_vinit(res_state, int); 112 #ifdef COMPAT__RES 113 /* 114 * Compatibility with program that were accessing _res directly 115 * to set options. We keep another struct res that is the same 116 * size as the original res structure, and then copy fields to 117 * it so that we achieve the same initialization 118 */ 119 extern void *__res_get_old_state(void); 120 extern void __res_put_old_state(void *); 121 res_state ores = __res_get_old_state(); 122 123 if (ores->options != 0) 124 _nres.options = ores->options; 125 if (ores->retrans != 0) 126 _nres.retrans = ores->retrans; 127 if (ores->retry != 0) 128 _nres.retry = ores->retry; 129 #endif 130 131 /* 132 * These three fields used to be statically initialized. This made 133 * it hard to use this code in a shared library. It is necessary, 134 * now that we're doing dynamic initialization here, that we preserve 135 * the old semantics: if an application modifies one of these three 136 * fields of _res before res_init() is called, res_init() will not 137 * alter them. Of course, if an application is setting them to 138 * _zero_ before calling res_init(), hoping to override what used 139 * to be the static default, we can't detect it and unexpected results 140 * will follow. Zero for any of these fields would make no sense, 141 * so one can safely assume that the applications were already getting 142 * unexpected results. 143 * 144 * _nres.options is tricky since some apps were known to diddle the bits 145 * before res_init() was first called. We can't replicate that semantic 146 * with dynamic initialization (they may have turned bits off that are 147 * set in RES_DEFAULT). Our solution is to declare such applications 148 * "broken". They could fool us by setting RES_INIT but none do (yet). 149 */ 150 if (!_nres.retrans) 151 _nres.retrans = RES_TIMEOUT; 152 if (!_nres.retry) 153 _nres.retry = 4; 154 if (!(_nres.options & RES_INIT)) 155 _nres.options = RES_DEFAULT; 156 157 /* 158 * This one used to initialize implicitly to zero, so unless the app 159 * has set it to something in particular, we can randomize it now. 160 */ 161 if (!_nres.id) 162 _nres.id = res_randomid(); 163 164 rv = __res_vinit(&_nres, 1); 165 #ifdef COMPAT__RES 166 __res_put_old_state(&_nres); 167 #endif 168 return rv; 169 } 170 171 void 172 p_query(const u_char *msg) { 173 fp_query(msg, stdout); 174 } 175 176 void 177 fp_query(const u_char *msg, FILE *file) { 178 fp_nquery(msg, PACKETSZ, file); 179 } 180 181 void 182 fp_nquery(const u_char *msg, int len, FILE *file) { 183 if ((_nres.options & RES_INIT) == 0U && res_init() == -1) 184 return; 185 186 res_pquery(&_nres, msg, len, file); 187 } 188 189 int 190 res_mkquery(int op, /*!< opcode of query */ 191 const char *dname, /*!< domain name */ 192 int class, int type, /*!< class and type of query */ 193 const u_char *data, /*!< resource record data */ 194 int datalen, /*!< length of data */ 195 const u_char *newrr_in, /*!< new rr for modify or append */ 196 u_char *buf, /*!< buffer to put query */ 197 int buflen) /*!< size of buffer */ 198 { 199 if ((_nres.options & RES_INIT) == 0U && res_init() == -1) { 200 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 201 return (-1); 202 } 203 return (res_nmkquery(&_nres, op, dname, class, type, 204 data, datalen, 205 newrr_in, buf, buflen)); 206 } 207 208 #ifdef _LIBRESOLV 209 int 210 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { 211 if ((_nres.options & RES_INIT) == 0U && res_init() == -1) { 212 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 213 return (-1); 214 } 215 216 return (res_nmkupdate(&_nres, rrecp_in, buf, buflen)); 217 } 218 #endif 219 220 int 221 res_query(const char *name, /*!< domain name */ 222 int class, int type, /*!< class and type of query */ 223 u_char *answer, /*!< buffer to put answer */ 224 int anslen) /*!< size of answer buffer */ 225 { 226 if ((_nres.options & RES_INIT) == 0U && res_init() == -1) { 227 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 228 return (-1); 229 } 230 return (res_nquery(&_nres, name, class, type, answer, anslen)); 231 } 232 233 void 234 res_send_setqhook(res_send_qhook hook) { 235 _nres.qhook = hook; 236 } 237 238 void 239 res_send_setrhook(res_send_rhook hook) { 240 _nres.rhook = hook; 241 } 242 243 int 244 res_isourserver(const struct sockaddr_in *inp) { 245 return (res_ourserver_p(&_nres, (const struct sockaddr *)(const void *)inp)); 246 } 247 248 int 249 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { 250 if ((_nres.options & RES_INIT) == 0U && res_init() == -1) { 251 /* errno should have been set by res_init() in this case. */ 252 return (-1); 253 } 254 255 return (res_nsend(&_nres, buf, buflen, ans, anssiz)); 256 } 257 258 #ifdef _LIBRESOLV 259 int 260 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, 261 u_char *ans, int anssiz) 262 { 263 if ((_nres.options & RES_INIT) == 0U && res_init() == -1) { 264 /* errno should have been set by res_init() in this case. */ 265 return (-1); 266 } 267 268 return (res_nsendsigned(&_nres, buf, buflen, key, ans, anssiz)); 269 } 270 #endif 271 272 void 273 res_close(void) { 274 res_nclose(&_nres); 275 } 276 277 #ifdef _LIBRESOLV 278 int 279 res_update(ns_updrec *rrecp_in) { 280 if ((_nres.options & RES_INIT) == 0U && res_init() == -1) { 281 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 282 return (-1); 283 } 284 285 return (res_nupdate(&_nres, rrecp_in, NULL)); 286 } 287 #endif 288 289 int 290 res_search(const char *name, /*!< domain name */ 291 int class, int type, /*!< class and type of query */ 292 u_char *answer, /*!< buffer to put answer */ 293 int anslen) /*!< size of answer */ 294 { 295 if ((_nres.options & RES_INIT) == 0U && res_init() == -1) { 296 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 297 return (-1); 298 } 299 300 return (res_nsearch(&_nres, name, class, type, answer, anslen)); 301 } 302 303 int 304 res_querydomain(const char *name, 305 const char *domain, 306 int class, int type, /*!< class and type of query */ 307 u_char *answer, /*!< buffer to put answer */ 308 int anslen) /*!< size of answer */ 309 { 310 if ((_nres.options & RES_INIT) == 0U && res_init() == -1) { 311 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 312 return (-1); 313 } 314 315 return (res_nquerydomain(&_nres, name, domain, 316 class, type, 317 answer, anslen)); 318 } 319 320 int 321 res_opt(int a, u_char *b, int c, int d) 322 { 323 return res_nopt(&_nres, a, b, c, d); 324 } 325 326 const char * 327 hostalias(const char *name) { 328 static char abuf[MAXDNAME]; 329 330 return (res_hostalias(&_nres, name, abuf, sizeof abuf)); 331 } 332 333 #ifdef ultrix 334 int 335 local_hostname_length(const char *hostname) { 336 int len_host, len_domain; 337 338 if (!*_nres.defdname) 339 res_init(); 340 len_host = strlen(hostname); 341 len_domain = strlen(_nres.defdname); 342 if (len_host > len_domain && 343 !strcasecmp(hostname + len_host - len_domain, _nres.defdname) && 344 hostname[len_host - len_domain - 1] == '.') 345 return (len_host - len_domain - 1); 346 return (0); 347 } 348 #endif /*ultrix*/ 349 350 #endif 351 352 /*! \file */ 353
Indexes created Mon Sep 22 05:09:51 GMT 2025