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 * $Id: res_data.c,v 1.5 2007/09/14 05:32:25 marka Exp $ 18 */ 19 20 #include "port_before.h" 21 22 #include <sys/types.h> 23 #include <sys/param.h> 24 #include <sys/socket.h> 25 #include <sys/time.h> 26 27 #include <netinet/in.h> 28 #include <arpa/inet.h> 29 #include <arpa/nameser.h> 30 31 #include <ctype.h> 32 #include <netdb.h> 33 #include <resolv.h> 34 #include <res_update.h> 35 #include <stdio.h> 36 #include <stdlib.h> 37 #include <string.h> 38 #include <unistd.h> 39 40 #include "port_after.h" 41 #ifndef _LIBC 42 #undef _res 43 #endif 44 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 #ifndef _LIBC 77 struct __res_state _res 78 # if defined(__BIND_RES_TEXT) 79 = { RES_TIMEOUT, } /*%< Motorola, et al. */ 80 # endif 81 ; 82 #endif /* !_LIBC */ 83 84 #if defined(DO_PTHREADS) || defined(__linux) 85 #define _res (*__res_state()) 86 #endif 87 88 /* Proto. */ 89 90 int res_ourserver_p(const res_state, const struct sockaddr_in *); 91 92 int 93 res_init(void) { 94 extern int __res_vinit(res_state, int); 95 96 /* 97 * These three fields used to be statically initialized. This made 98 * it hard to use this code in a shared library. It is necessary, 99 * now that we're doing dynamic initialization here, that we preserve 100 * the old semantics: if an application modifies one of these three 101 * fields of _res before res_init() is called, res_init() will not 102 * alter them. Of course, if an application is setting them to 103 * _zero_ before calling res_init(), hoping to override what used 104 * to be the static default, we can't detect it and unexpected results 105 * will follow. Zero for any of these fields would make no sense, 106 * so one can safely assume that the applications were already getting 107 * unexpected results. 108 * 109 * _res.options is tricky since some apps were known to diddle the bits 110 * before res_init() was first called. We can't replicate that semantic 111 * with dynamic initialization (they may have turned bits off that are 112 * set in RES_DEFAULT). Our solution is to declare such applications 113 * "broken". They could fool us by setting RES_INIT but none do (yet). 114 */ 115 if (!_res.retrans) 116 _res.retrans = RES_TIMEOUT; 117 if (!_res.retry) 118 #ifndef _LIBC 119 _res.retry = 4; 120 #else 121 _res.retry = RES_DFLRETRY; 122 #endif 123 if (!(_res.options & RES_INIT)) 124 _res.options = RES_DEFAULT; 125 126 /* 127 * This one used to initialize implicitly to zero, so unless the app 128 * has set it to something in particular, we can randomize it now. 129 */ 130 if (!_res.id) 131 _res.id = res_randomid(); 132 133 return (__res_vinit(&_res, 1)); 134 } 135 136 void 137 p_query(const u_char *msg) { 138 fp_query(msg, stdout); 139 } 140 141 void 142 fp_query(const u_char *msg, FILE *file) { 143 fp_nquery(msg, PACKETSZ, file); 144 } 145 146 void 147 fp_nquery(const u_char *msg, int len, FILE *file) { 148 if ((_res.options & RES_INIT) == 0U && res_init() == -1) 149 return; 150 151 res_pquery(&_res, msg, len, file); 152 } 153 154 int 155 res_mkquery(int op, /*!< opcode of query */ 156 const char *dname, /*!< domain name */ 157 int class, int type, /*!< class and type of query */ 158 const u_char *data, /*!< resource record data */ 159 int datalen, /*!< length of data */ 160 const u_char *newrr_in, /*!< new rr for modify or append */ 161 u_char *buf, /*!< buffer to put query */ 162 int buflen) /*!< size of buffer */ 163 { 164 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 165 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 166 return (-1); 167 } 168 return (res_nmkquery(&_res, op, dname, class, type, 169 data, datalen, 170 newrr_in, buf, buflen)); 171 } 172 173 int 174 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { 175 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 176 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 177 return (-1); 178 } 179 180 return (res_nmkupdate(&_res, rrecp_in, buf, buflen)); 181 } 182 183 int 184 res_query(const char *name, /*!< domain name */ 185 int class, int type, /*!< class and type of query */ 186 u_char *answer, /*!< buffer to put answer */ 187 int anslen) /*!< size of answer buffer */ 188 { 189 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 190 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 191 return (-1); 192 } 193 return (res_nquery(&_res, name, class, type, answer, anslen)); 194 } 195 196 #ifndef _LIBC 197 void 198 res_send_setqhook(res_send_qhook hook) { 199 _res.qhook = hook; 200 } 201 202 void 203 res_send_setrhook(res_send_rhook hook) { 204 _res.rhook = hook; 205 } 206 #endif 207 208 int 209 res_isourserver(const struct sockaddr_in *inp) { 210 return (res_ourserver_p(&_res, inp)); 211 } 212 213 int 214 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { 215 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 216 /* errno should have been set by res_init() in this case. */ 217 return (-1); 218 } 219 220 return (res_nsend(&_res, buf, buflen, ans, anssiz)); 221 } 222 223 #ifndef _LIBC 224 int 225 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, 226 u_char *ans, int anssiz) 227 { 228 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 229 /* errno should have been set by res_init() in this case. */ 230 return (-1); 231 } 232 233 return (res_nsendsigned(&_res, buf, buflen, key, ans, anssiz)); 234 } 235 #endif 236 237 void 238 res_close(void) { 239 res_nclose(&_res); 240 } 241 242 int 243 res_update(ns_updrec *rrecp_in) { 244 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 245 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 246 return (-1); 247 } 248 249 return (res_nupdate(&_res, rrecp_in, NULL)); 250 } 251 252 int 253 res_search(const char *name, /*!< domain name */ 254 int class, int type, /*!< class and type of query */ 255 u_char *answer, /*!< buffer to put answer */ 256 int anslen) /*!< size of answer */ 257 { 258 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 259 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 260 return (-1); 261 } 262 263 return (res_nsearch(&_res, name, class, type, answer, anslen)); 264 } 265 266 int 267 res_querydomain(const char *name, 268 const char *domain, 269 int class, int type, /*!< class and type of query */ 270 u_char *answer, /*!< buffer to put answer */ 271 int anslen) /*!< size of answer */ 272 { 273 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 274 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 275 return (-1); 276 } 277 278 return (res_nquerydomain(&_res, name, domain, 279 class, type, 280 answer, anslen)); 281 } 282 283 #ifdef _LIBC 284 int 285 res_opt(int n0, u_char *buf, int buflen, int anslen) 286 { 287 return (res_nopt(&_res, n0, buf, buflen, anslen)); 288 } 289 #endif 290 291 const char * 292 hostalias(const char *name) { 293 static char abuf[MAXDNAME]; 294 295 return (res_hostalias(&_res, name, abuf, sizeof abuf)); 296 } 297 298 #ifdef ultrix 299 int 300 local_hostname_length(const char *hostname) { 301 int len_host, len_domain; 302 303 if (!*_res.defdname) 304 res_init(); 305 len_host = strlen(hostname); 306 len_domain = strlen(_res.defdname); 307 if (len_host > len_domain && 308 !strcasecmp(hostname + len_host - len_domain, _res.defdname) && 309 hostname[len_host - len_domain - 1] == '.') 310 return (len_host - len_domain - 1); 311 return (0); 312 } 313 #endif /*ultrix*/ 314 315 #ifdef _LIBC 316 /* 317 * Weak aliases for applications that use certain private entry points, 318 * and fail to include <resolv.h>. 319 */ 320 #undef res_init 321 __weak_reference(__res_init, res_init); 322 #undef p_query 323 __weak_reference(__p_query, p_query); 324 #undef res_mkquery 325 __weak_reference(__res_mkquery, res_mkquery); 326 #undef res_query 327 __weak_reference(__res_query, res_query); 328 #undef res_send 329 __weak_reference(__res_send, res_send); 330 #undef res_close 331 __weak_reference(__res_close, _res_close); 332 #undef res_search 333 __weak_reference(__res_search, res_search); 334 #undef res_querydomain 335 __weak_reference(__res_querydomain, res_querydomain); 336 #endif 337 338 #endif 339 /*! \file */ 340