1 /* 2 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 3 * Copyright (c) 1995-1999 by Internet Software Consortium. 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 15 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #if defined(LIBC_SCCS) && !defined(lint) 19 static const char rcsid[] = "$Id: res_data.c,v 1.5 2007/09/14 05:32:25 marka Exp $"; 20 #endif /* LIBC_SCCS and not lint */ 21 22 #include "port_before.h" 23 24 #include <sys/types.h> 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 #ifndef _LIBC 44 #undef _res 45 #endif 46 47 48 const char *_res_opcodes[] = { 49 "QUERY", 50 "IQUERY", 51 "CQUERYM", 52 "CQUERYU", /*%< experimental */ 53 "NOTIFY", /*%< experimental */ 54 "UPDATE", 55 "6", 56 "7", 57 "8", 58 "9", 59 "10", 60 "11", 61 "12", 62 "13", 63 "ZONEINIT", 64 "ZONEREF", 65 }; 66 67 #ifdef BIND_UPDATE 68 const char *_res_sectioncodes[] = { 69 "ZONE", 70 "PREREQUISITES", 71 "UPDATE", 72 "ADDITIONAL", 73 }; 74 #endif 75 76 #undef _res 77 #ifndef __BIND_NOSTATIC 78 #ifndef _LIBC 79 struct __res_state _res 80 # if defined(__BIND_RES_TEXT) 81 = { RES_TIMEOUT, } /*%< Motorola, et al. */ 82 # endif 83 ; 84 #endif /* !_LIBC */ 85 86 #if defined(DO_PTHREADS) || defined(__linux) 87 #define _res (*__res_state()) 88 #endif 89 90 /* Proto. */ 91 92 int res_ourserver_p(const res_state, const struct sockaddr_in *); 93 94 int 95 res_init(void) { 96 extern int __res_vinit(res_state, int); 97 98 /* 99 * These three fields used to be statically initialized. This made 100 * it hard to use this code in a shared library. It is necessary, 101 * now that we're doing dynamic initialization here, that we preserve 102 * the old semantics: if an application modifies one of these three 103 * fields of _res before res_init() is called, res_init() will not 104 * alter them. Of course, if an application is setting them to 105 * _zero_ before calling res_init(), hoping to override what used 106 * to be the static default, we can't detect it and unexpected results 107 * will follow. Zero for any of these fields would make no sense, 108 * so one can safely assume that the applications were already getting 109 * unexpected results. 110 * 111 * _res.options is tricky since some apps were known to diddle the bits 112 * before res_init() was first called. We can't replicate that semantic 113 * with dynamic initialization (they may have turned bits off that are 114 * set in RES_DEFAULT). Our solution is to declare such applications 115 * "broken". They could fool us by setting RES_INIT but none do (yet). 116 */ 117 if (!_res.retrans) 118 _res.retrans = RES_TIMEOUT; 119 if (!_res.retry) 120 #ifndef _LIBC 121 _res.retry = 4; 122 #else 123 _res.retry = RES_DFLRETRY; 124 #endif 125 if (!(_res.options & RES_INIT)) 126 _res.options = RES_DEFAULT; 127 128 /* 129 * This one used to initialize implicitly to zero, so unless the app 130 * has set it to something in particular, we can randomize it now. 131 */ 132 if (!_res.id) 133 _res.id = res_randomid(); 134 135 return (__res_vinit(&_res, 1)); 136 } 137 138 void 139 p_query(const u_char *msg) { 140 fp_query(msg, stdout); 141 } 142 143 void 144 fp_query(const u_char *msg, FILE *file) { 145 fp_nquery(msg, PACKETSZ, file); 146 } 147 148 void 149 fp_nquery(const u_char *msg, int len, FILE *file) { 150 if ((_res.options & RES_INIT) == 0U && res_init() == -1) 151 return; 152 153 res_pquery(&_res, msg, len, file); 154 } 155 156 int 157 res_mkquery(int op, /*!< opcode of query */ 158 const char *dname, /*!< domain name */ 159 int class, int type, /*!< class and type of query */ 160 const u_char *data, /*!< resource record data */ 161 int datalen, /*!< length of data */ 162 const u_char *newrr_in, /*!< new rr for modify or append */ 163 u_char *buf, /*!< buffer to put query */ 164 int buflen) /*!< size of buffer */ 165 { 166 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 167 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 168 return (-1); 169 } 170 return (res_nmkquery(&_res, op, dname, class, type, 171 data, datalen, 172 newrr_in, buf, buflen)); 173 } 174 175 int 176 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { 177 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 178 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 179 return (-1); 180 } 181 182 return (res_nmkupdate(&_res, rrecp_in, buf, buflen)); 183 } 184 185 int 186 res_query(const char *name, /*!< domain name */ 187 int class, int type, /*!< class and type of query */ 188 u_char *answer, /*!< buffer to put answer */ 189 int anslen) /*!< size of answer buffer */ 190 { 191 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 192 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 193 return (-1); 194 } 195 return (res_nquery(&_res, name, class, type, answer, anslen)); 196 } 197 198 #ifndef _LIBC 199 void 200 res_send_setqhook(res_send_qhook hook) { 201 _res.qhook = hook; 202 } 203 204 void 205 res_send_setrhook(res_send_rhook hook) { 206 _res.rhook = hook; 207 } 208 #endif 209 210 int 211 res_isourserver(const struct sockaddr_in *inp) { 212 return (res_ourserver_p(&_res, inp)); 213 } 214 215 int 216 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { 217 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 218 /* errno should have been set by res_init() in this case. */ 219 return (-1); 220 } 221 222 return (res_nsend(&_res, buf, buflen, ans, anssiz)); 223 } 224 225 #ifndef _LIBC 226 int 227 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, 228 u_char *ans, int anssiz) 229 { 230 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 231 /* errno should have been set by res_init() in this case. */ 232 return (-1); 233 } 234 235 return (res_nsendsigned(&_res, buf, buflen, key, ans, anssiz)); 236 } 237 #endif 238 239 void 240 res_close(void) { 241 res_nclose(&_res); 242 } 243 244 int 245 res_update(ns_updrec *rrecp_in) { 246 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 247 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 248 return (-1); 249 } 250 251 return (res_nupdate(&_res, rrecp_in, NULL)); 252 } 253 254 int 255 res_search(const char *name, /*!< domain name */ 256 int class, int type, /*!< class and type of query */ 257 u_char *answer, /*!< buffer to put answer */ 258 int anslen) /*!< size of answer */ 259 { 260 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 261 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 262 return (-1); 263 } 264 265 return (res_nsearch(&_res, name, class, type, answer, anslen)); 266 } 267 268 int 269 res_querydomain(const char *name, 270 const char *domain, 271 int class, int type, /*!< class and type of query */ 272 u_char *answer, /*!< buffer to put answer */ 273 int anslen) /*!< size of answer */ 274 { 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_nquerydomain(&_res, name, domain, 281 class, type, 282 answer, anslen)); 283 } 284 285 #ifdef _LIBC 286 int 287 res_opt(int n0, u_char *buf, int buflen, int anslen) 288 { 289 return (res_nopt(&_res, n0, buf, buflen, anslen)); 290 } 291 #endif 292 293 const char * 294 hostalias(const char *name) { 295 static char abuf[MAXDNAME]; 296 297 return (res_hostalias(&_res, name, abuf, sizeof abuf)); 298 } 299 300 #ifdef ultrix 301 int 302 local_hostname_length(const char *hostname) { 303 int len_host, len_domain; 304 305 if (!*_res.defdname) 306 res_init(); 307 len_host = strlen(hostname); 308 len_domain = strlen(_res.defdname); 309 if (len_host > len_domain && 310 !strcasecmp(hostname + len_host - len_domain, _res.defdname) && 311 hostname[len_host - len_domain - 1] == '.') 312 return (len_host - len_domain - 1); 313 return (0); 314 } 315 #endif /*ultrix*/ 316 317 #ifdef _LIBC 318 /* 319 * Weak aliases for applications that use certain private entry points, 320 * and fail to include <resolv.h>. 321 */ 322 #undef res_init 323 __weak_reference(__res_init, res_init); 324 #undef p_query 325 __weak_reference(__p_query, p_query); 326 #undef res_mkquery 327 __weak_reference(__res_mkquery, res_mkquery); 328 #undef res_query 329 __weak_reference(__res_query, res_query); 330 #undef res_send 331 __weak_reference(__res_send, res_send); 332 #undef res_close 333 __weak_reference(__res_close, _res_close); 334 #undef res_search 335 __weak_reference(__res_search, res_search); 336 #undef res_querydomain 337 __weak_reference(__res_querydomain, res_querydomain); 338 #endif 339 340 #endif 341 /*! \file */ 342