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 <sys/cdefs.h> 24 #include "port_before.h" 25 26 #include <sys/param.h> 27 #include <sys/socket.h> 28 #include <sys/time.h> 29 30 #include <netinet/in.h> 31 #include <arpa/inet.h> 32 #include <arpa/nameser.h> 33 34 #include <ctype.h> 35 #include <netdb.h> 36 #include <resolv.h> 37 #include <res_update.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 #include <unistd.h> 42 43 #include "port_after.h" 44 45 const char *_res_opcodes[] = { 46 "QUERY", 47 "IQUERY", 48 "CQUERYM", 49 "CQUERYU", /*%< experimental */ 50 "NOTIFY", /*%< experimental */ 51 "UPDATE", 52 "6", 53 "7", 54 "8", 55 "9", 56 "10", 57 "11", 58 "12", 59 "13", 60 "ZONEINIT", 61 "ZONEREF", 62 }; 63 64 #ifdef BIND_UPDATE 65 const char *_res_sectioncodes[] = { 66 "ZONE", 67 "PREREQUISITES", 68 "UPDATE", 69 "ADDITIONAL", 70 }; 71 #endif 72 73 #ifndef __BIND_NOSTATIC 74 75 /* Proto. */ 76 77 int res_ourserver_p(const res_state, const struct sockaddr_in *); 78 79 __noinline int 80 res_init(void) { 81 extern int __res_vinit(res_state, int); 82 res_state statp = &_res; 83 84 /* 85 * These three fields used to be statically initialized. This made 86 * it hard to use this code in a shared library. It is necessary, 87 * now that we're doing dynamic initialization here, that we preserve 88 * the old semantics: if an application modifies one of these three 89 * fields of _res before res_init() is called, res_init() will not 90 * alter them. Of course, if an application is setting them to 91 * _zero_ before calling res_init(), hoping to override what used 92 * to be the static default, we can't detect it and unexpected results 93 * will follow. Zero for any of these fields would make no sense, 94 * so one can safely assume that the applications were already getting 95 * unexpected results. 96 * 97 * _res.options is tricky since some apps were known to diddle the bits 98 * before res_init() was first called. We can't replicate that semantic 99 * with dynamic initialization (they may have turned bits off that are 100 * set in RES_DEFAULT). Our solution is to declare such applications 101 * "broken". They could fool us by setting RES_INIT but none do (yet). 102 */ 103 if (!statp->retrans) 104 statp->retrans = RES_TIMEOUT; 105 if (!statp->retry) 106 statp->retry = RES_DFLRETRY; 107 if (!(statp->options & RES_INIT)) 108 statp->options = RES_DEFAULT; 109 110 return (__res_vinit(statp, 1)); 111 } 112 113 void 114 p_query(const u_char *msg) { 115 fp_query(msg, stdout); 116 } 117 118 void 119 fp_query(const u_char *msg, FILE *file) { 120 fp_nquery(msg, PACKETSZ, file); 121 } 122 123 void 124 fp_nquery(const u_char *msg, int len, FILE *file) { 125 res_state statp = &_res; 126 if ((statp->options & RES_INIT) == 0U && res_init() == -1) 127 return; 128 129 res_pquery(statp, msg, len, file); 130 } 131 132 int 133 res_mkquery(int op, /*!< opcode of query */ 134 const char *dname, /*!< domain name */ 135 int class, int type, /*!< class and type of query */ 136 const u_char *data, /*!< resource record data */ 137 int datalen, /*!< length of data */ 138 const u_char *newrr_in, /*!< new rr for modify or append */ 139 u_char *buf, /*!< buffer to put query */ 140 int buflen) /*!< size of buffer */ 141 { 142 res_state statp = &_res; 143 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 144 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 145 return (-1); 146 } 147 return (res_nmkquery(statp, op, dname, class, type, 148 data, datalen, 149 newrr_in, buf, buflen)); 150 } 151 152 int 153 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { 154 res_state statp = &_res; 155 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 156 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 157 return (-1); 158 } 159 160 return (res_nmkupdate(statp, rrecp_in, buf, buflen)); 161 } 162 163 int 164 res_query(const char *name, /*!< domain name */ 165 int class, int type, /*!< class and type of query */ 166 u_char *answer, /*!< buffer to put answer */ 167 int anslen) /*!< size of answer buffer */ 168 { 169 res_state statp = &_res; 170 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 171 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 172 return (-1); 173 } 174 return (res_nquery(statp, name, class, type, answer, anslen)); 175 } 176 177 #ifndef _LIBC 178 void 179 res_send_setqhook(res_send_qhook hook) { 180 _res.qhook = hook; 181 } 182 183 void 184 res_send_setrhook(res_send_rhook hook) { 185 _res.rhook = hook; 186 } 187 #endif 188 189 int 190 res_isourserver(const struct sockaddr_in *inp) { 191 return (res_ourserver_p(&_res, inp)); 192 } 193 194 int 195 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { 196 res_state statp = &_res; 197 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 198 /* errno should have been set by res_init() in this case. */ 199 return (-1); 200 } 201 202 return (res_nsend(statp, buf, buflen, ans, anssiz)); 203 } 204 205 #ifndef _LIBC 206 int 207 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, 208 u_char *ans, int anssiz) 209 { 210 res_state statp = &_res; 211 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 212 /* errno should have been set by res_init() in this case. */ 213 return (-1); 214 } 215 216 return (res_nsendsigned(statp, buf, buflen, key, ans, anssiz)); 217 } 218 #endif 219 220 void 221 res_close(void) { 222 res_nclose(&_res); 223 } 224 225 int 226 res_update(ns_updrec *rrecp_in) { 227 res_state statp = &_res; 228 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 229 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 230 return (-1); 231 } 232 233 return (res_nupdate(statp, rrecp_in, NULL)); 234 } 235 236 int 237 res_search(const char *name, /*!< domain name */ 238 int class, int type, /*!< class and type of query */ 239 u_char *answer, /*!< buffer to put answer */ 240 int anslen) /*!< size of answer */ 241 { 242 res_state statp = &_res; 243 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 244 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 245 return (-1); 246 } 247 248 return (res_nsearch(statp, name, class, type, answer, anslen)); 249 } 250 251 int 252 res_querydomain(const char *name, 253 const char *domain, 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 res_state statp = &_res; 259 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 260 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 261 return (-1); 262 } 263 264 return (res_nquerydomain(statp, name, domain, 265 class, type, 266 answer, anslen)); 267 } 268 269 u_int 270 res_randomid(void) { 271 res_state statp = &_res; 272 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 273 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 274 return (-1); 275 } 276 277 return (res_nrandomid(statp)); 278 } 279 280 int 281 res_opt(int n0, u_char *buf, int buflen, int anslen) 282 { 283 return (res_nopt(&_res, n0, buf, buflen, anslen)); 284 } 285 286 const char * 287 hostalias(const char *name) { 288 static char abuf[MAXDNAME]; 289 290 return (res_hostalias(&_res, name, abuf, sizeof abuf)); 291 } 292 293 #ifdef ultrix 294 int 295 local_hostname_length(const char *hostname) { 296 int len_host, len_domain; 297 res_state statp; 298 299 statp = &_res; 300 if (!*statp->defdname) 301 res_init(); 302 len_host = strlen(hostname); 303 len_domain = strlen(statp->defdname); 304 if (len_host > len_domain && 305 !strcasecmp(hostname + len_host - len_domain, statp->defdname) && 306 hostname[len_host - len_domain - 1] == '.') 307 return (len_host - len_domain - 1); 308 return (0); 309 } 310 #endif /*ultrix*/ 311 312 /* 313 * Weak aliases for applications that use certain private entry points, 314 * and fail to include <resolv.h>. 315 */ 316 #undef res_init 317 __weak_reference(__res_init, res_init); 318 #undef p_query 319 __weak_reference(__p_query, p_query); 320 #undef res_mkquery 321 __weak_reference(__res_mkquery, res_mkquery); 322 #undef res_query 323 __weak_reference(__res_query, res_query); 324 #undef res_send 325 __weak_reference(__res_send, res_send); 326 #undef res_close 327 __weak_reference(__res_close, _res_close); 328 #undef res_search 329 __weak_reference(__res_search, res_search); 330 #undef res_querydomain 331 __weak_reference(__res_querydomain, res_querydomain); 332 333 #endif 334 335 /*! \file */ 336