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 $"; 22 #endif /* LIBC_SCCS and not lint */ 23 #include <sys/cdefs.h> 24 __FBSDID("$FreeBSD$"); 25 26 #include "port_before.h" 27 28 #include <sys/param.h> 29 #include <sys/socket.h> 30 #include <sys/time.h> 31 32 #include <netinet/in.h> 33 #include <arpa/inet.h> 34 #include <arpa/nameser.h> 35 36 #include <ctype.h> 37 #include <netdb.h> 38 #include <resolv.h> 39 #include <res_update.h> 40 #include <stdio.h> 41 #include <stdlib.h> 42 #include <string.h> 43 #include <unistd.h> 44 45 #include "port_after.h" 46 47 const char *_res_opcodes[] = { 48 "QUERY", 49 "IQUERY", 50 "CQUERYM", 51 "CQUERYU", /*%< experimental */ 52 "NOTIFY", /*%< experimental */ 53 "UPDATE", 54 "6", 55 "7", 56 "8", 57 "9", 58 "10", 59 "11", 60 "12", 61 "13", 62 "ZONEINIT", 63 "ZONEREF", 64 }; 65 66 #ifdef BIND_UPDATE 67 const char *_res_sectioncodes[] = { 68 "ZONE", 69 "PREREQUISITES", 70 "UPDATE", 71 "ADDITIONAL", 72 }; 73 #endif 74 75 #ifndef __BIND_NOSTATIC 76 77 /* Proto. */ 78 79 int res_ourserver_p(const res_state, const struct sockaddr_in *); 80 81 __noinline int 82 res_init(void) { 83 extern int __res_vinit(res_state, int); 84 res_state statp = &_res; 85 86 /* 87 * These three fields used to be statically initialized. This made 88 * it hard to use this code in a shared library. It is necessary, 89 * now that we're doing dynamic initialization here, that we preserve 90 * the old semantics: if an application modifies one of these three 91 * fields of _res before res_init() is called, res_init() will not 92 * alter them. Of course, if an application is setting them to 93 * _zero_ before calling res_init(), hoping to override what used 94 * to be the static default, we can't detect it and unexpected results 95 * will follow. Zero for any of these fields would make no sense, 96 * so one can safely assume that the applications were already getting 97 * unexpected results. 98 * 99 * _res.options is tricky since some apps were known to diddle the bits 100 * before res_init() was first called. We can't replicate that semantic 101 * with dynamic initialization (they may have turned bits off that are 102 * set in RES_DEFAULT). Our solution is to declare such applications 103 * "broken". They could fool us by setting RES_INIT but none do (yet). 104 */ 105 if (!statp->retrans) 106 statp->retrans = RES_TIMEOUT; 107 if (!statp->retry) 108 statp->retry = RES_DFLRETRY; 109 if (!(statp->options & RES_INIT)) 110 statp->options = RES_DEFAULT; 111 112 return (__res_vinit(statp, 1)); 113 } 114 115 void 116 p_query(const u_char *msg) { 117 fp_query(msg, stdout); 118 } 119 120 void 121 fp_query(const u_char *msg, FILE *file) { 122 fp_nquery(msg, PACKETSZ, file); 123 } 124 125 void 126 fp_nquery(const u_char *msg, int len, FILE *file) { 127 res_state statp = &_res; 128 if ((statp->options & RES_INIT) == 0U && res_init() == -1) 129 return; 130 131 res_pquery(statp, msg, len, file); 132 } 133 134 int 135 res_mkquery(int op, /*!< opcode of query */ 136 const char *dname, /*!< domain name */ 137 int class, int type, /*!< class and type of query */ 138 const u_char *data, /*!< resource record data */ 139 int datalen, /*!< length of data */ 140 const u_char *newrr_in, /*!< new rr for modify or append */ 141 u_char *buf, /*!< buffer to put query */ 142 int buflen) /*!< size of buffer */ 143 { 144 res_state statp = &_res; 145 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 146 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 147 return (-1); 148 } 149 return (res_nmkquery(statp, op, dname, class, type, 150 data, datalen, 151 newrr_in, buf, buflen)); 152 } 153 154 int 155 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { 156 res_state statp = &_res; 157 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 158 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 159 return (-1); 160 } 161 162 return (res_nmkupdate(statp, rrecp_in, buf, buflen)); 163 } 164 165 int 166 res_query(const char *name, /*!< domain name */ 167 int class, int type, /*!< class and type of query */ 168 u_char *answer, /*!< buffer to put answer */ 169 int anslen) /*!< size of answer buffer */ 170 { 171 res_state statp = &_res; 172 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 173 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 174 return (-1); 175 } 176 return (res_nquery(statp, name, class, type, answer, anslen)); 177 } 178 179 #ifndef _LIBC 180 void 181 res_send_setqhook(res_send_qhook hook) { 182 _res.qhook = hook; 183 } 184 185 void 186 res_send_setrhook(res_send_rhook hook) { 187 _res.rhook = hook; 188 } 189 #endif 190 191 int 192 res_isourserver(const struct sockaddr_in *inp) { 193 return (res_ourserver_p(&_res, inp)); 194 } 195 196 int 197 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { 198 res_state statp = &_res; 199 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 200 /* errno should have been set by res_init() in this case. */ 201 return (-1); 202 } 203 204 return (res_nsend(statp, buf, buflen, ans, anssiz)); 205 } 206 207 #ifndef _LIBC 208 int 209 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, 210 u_char *ans, int anssiz) 211 { 212 res_state statp = &_res; 213 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 214 /* errno should have been set by res_init() in this case. */ 215 return (-1); 216 } 217 218 return (res_nsendsigned(statp, buf, buflen, key, ans, anssiz)); 219 } 220 #endif 221 222 void 223 res_close(void) { 224 res_nclose(&_res); 225 } 226 227 int 228 res_update(ns_updrec *rrecp_in) { 229 res_state statp = &_res; 230 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 231 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 232 return (-1); 233 } 234 235 return (res_nupdate(statp, rrecp_in, NULL)); 236 } 237 238 int 239 res_search(const char *name, /*!< domain name */ 240 int class, int type, /*!< class and type of query */ 241 u_char *answer, /*!< buffer to put answer */ 242 int anslen) /*!< size of answer */ 243 { 244 res_state statp = &_res; 245 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 246 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 247 return (-1); 248 } 249 250 return (res_nsearch(statp, name, class, type, answer, anslen)); 251 } 252 253 int 254 res_querydomain(const char *name, 255 const char *domain, 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 res_state statp = &_res; 261 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 262 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 263 return (-1); 264 } 265 266 return (res_nquerydomain(statp, name, domain, 267 class, type, 268 answer, anslen)); 269 } 270 271 u_int 272 res_randomid(void) { 273 res_state statp = &_res; 274 if ((statp->options & RES_INIT) == 0U && res_init() == -1) { 275 RES_SET_H_ERRNO(statp, NETDB_INTERNAL); 276 return (-1); 277 } 278 279 return (res_nrandomid(statp)); 280 } 281 282 int 283 res_opt(int n0, u_char *buf, int buflen, int anslen) 284 { 285 return (res_nopt(&_res, n0, buf, buflen, anslen)); 286 } 287 288 const char * 289 hostalias(const char *name) { 290 static char abuf[MAXDNAME]; 291 292 return (res_hostalias(&_res, name, abuf, sizeof abuf)); 293 } 294 295 #ifdef ultrix 296 int 297 local_hostname_length(const char *hostname) { 298 int len_host, len_domain; 299 res_state statp; 300 301 statp = &_res; 302 if (!*statp->defdname) 303 res_init(); 304 len_host = strlen(hostname); 305 len_domain = strlen(statp->defdname); 306 if (len_host > len_domain && 307 !strcasecmp(hostname + len_host - len_domain, statp->defdname) && 308 hostname[len_host - len_domain - 1] == '.') 309 return (len_host - len_domain - 1); 310 return (0); 311 } 312 #endif /*ultrix*/ 313 314 /* 315 * Weak aliases for applications that use certain private entry points, 316 * and fail to include <resolv.h>. 317 */ 318 #undef res_init 319 __weak_reference(__res_init, res_init); 320 #undef p_query 321 __weak_reference(__p_query, p_query); 322 #undef res_mkquery 323 __weak_reference(__res_mkquery, res_mkquery); 324 #undef res_query 325 __weak_reference(__res_query, res_query); 326 #undef res_send 327 __weak_reference(__res_send, res_send); 328 #undef res_close 329 __weak_reference(__res_close, _res_close); 330 #undef res_search 331 __weak_reference(__res_search, res_search); 332 #undef res_querydomain 333 __weak_reference(__res_querydomain, res_querydomain); 334 335 #endif 336 337 /*! \file */ 338