1 /* $NetBSD: res_data.c,v 1.7 2004/05/22 23:47:09 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 1.1.206.2 2004/03/16 12:34:18 marka Exp"; 24 #else 25 __RCSID("$NetBSD: res_data.c,v 1.7 2004/05/22 23:47:09 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 #undef _res 74 75 const char *_res_opcodes[] = { 76 "QUERY", 77 "IQUERY", 78 "CQUERYM", 79 "CQUERYU", /* experimental */ 80 "NOTIFY", /* experimental */ 81 "UPDATE", 82 "6", 83 "7", 84 "8", 85 "9", 86 "10", 87 "11", 88 "12", 89 "13", 90 "ZONEINIT", 91 "ZONEREF", 92 }; 93 94 #ifdef BIND_UPDATE 95 const char *_res_sectioncodes[] = { 96 "ZONE", 97 "PREREQUISITES", 98 "UPDATE", 99 "ADDITIONAL", 100 }; 101 #endif 102 103 #ifndef __BIND_NOSTATIC 104 struct __res_state _res 105 # if defined(__BIND_RES_TEXT) 106 = { RES_TIMEOUT, } /* Motorola, et al. */ 107 # endif 108 ; 109 110 /* Proto. */ 111 112 int res_ourserver_p(const res_state, const struct sockaddr *); 113 114 int 115 res_init(void) { 116 extern int __res_vinit(res_state, int); 117 118 /* 119 * These three fields used to be statically initialized. This made 120 * it hard to use this code in a shared library. It is necessary, 121 * now that we're doing dynamic initialization here, that we preserve 122 * the old semantics: if an application modifies one of these three 123 * fields of _res before res_init() is called, res_init() will not 124 * alter them. Of course, if an application is setting them to 125 * _zero_ before calling res_init(), hoping to override what used 126 * to be the static default, we can't detect it and unexpected results 127 * will follow. Zero for any of these fields would make no sense, 128 * so one can safely assume that the applications were already getting 129 * unexpected results. 130 * 131 * _res.options is tricky since some apps were known to diddle the bits 132 * before res_init() was first called. We can't replicate that semantic 133 * with dynamic initialization (they may have turned bits off that are 134 * set in RES_DEFAULT). Our solution is to declare such applications 135 * "broken". They could fool us by setting RES_INIT but none do (yet). 136 */ 137 if (!_res.retrans) 138 _res.retrans = RES_TIMEOUT; 139 if (!_res.retry) 140 _res.retry = 4; 141 if (!(_res.options & RES_INIT)) 142 _res.options = RES_DEFAULT; 143 144 /* 145 * This one used to initialize implicitly to zero, so unless the app 146 * has set it to something in particular, we can randomize it now. 147 */ 148 if (!_res.id) 149 _res.id = res_randomid(); 150 151 return (__res_vinit(&_res, 1)); 152 } 153 154 void 155 p_query(const u_char *msg) { 156 fp_query(msg, stdout); 157 } 158 159 void 160 fp_query(const u_char *msg, FILE *file) { 161 fp_nquery(msg, PACKETSZ, file); 162 } 163 164 void 165 fp_nquery(const u_char *msg, int len, FILE *file) { 166 if ((_res.options & RES_INIT) == 0U && res_init() == -1) 167 return; 168 169 res_pquery(&_res, msg, len, file); 170 } 171 172 int 173 res_mkquery(int op, /* opcode of query */ 174 const char *dname, /* domain name */ 175 int class, int type, /* class and type of query */ 176 const u_char *data, /* resource record data */ 177 int datalen, /* length of data */ 178 const u_char *newrr_in, /* new rr for modify or append */ 179 u_char *buf, /* buffer to put query */ 180 int buflen) /* size of buffer */ 181 { 182 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 183 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 184 return (-1); 185 } 186 return (res_nmkquery(&_res, op, dname, class, type, 187 data, datalen, 188 newrr_in, buf, buflen)); 189 } 190 191 #ifdef _LIBRESOLV 192 int 193 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { 194 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 195 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 196 return (-1); 197 } 198 199 return (res_nmkupdate(&_res, rrecp_in, buf, buflen)); 200 } 201 #endif 202 203 int 204 res_query(const char *name, /* domain name */ 205 int class, int type, /* class and type of query */ 206 u_char *answer, /* buffer to put answer */ 207 int anslen) /* size of answer buffer */ 208 { 209 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 210 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 211 return (-1); 212 } 213 return (res_nquery(&_res, name, class, type, answer, anslen)); 214 } 215 216 void 217 res_send_setqhook(res_send_qhook hook) { 218 _res.qhook = hook; 219 } 220 221 void 222 res_send_setrhook(res_send_rhook hook) { 223 _res.rhook = hook; 224 } 225 226 int 227 res_isourserver(const struct sockaddr_in *inp) { 228 return (res_ourserver_p(&_res, (const struct sockaddr *)(const void *)inp)); 229 } 230 231 int 232 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { 233 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 234 /* errno should have been set by res_init() in this case. */ 235 return (-1); 236 } 237 238 return (res_nsend(&_res, buf, buflen, ans, anssiz)); 239 } 240 241 #ifdef _LIBRESOLV 242 int 243 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, 244 u_char *ans, int anssiz) 245 { 246 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 247 /* errno should have been set by res_init() in this case. */ 248 return (-1); 249 } 250 251 return (res_nsendsigned(&_res, buf, buflen, key, ans, anssiz)); 252 } 253 #endif 254 255 void 256 res_close(void) { 257 res_nclose(&_res); 258 } 259 260 #ifdef _LIBRESOLV 261 int 262 res_update(ns_updrec *rrecp_in) { 263 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 264 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 265 return (-1); 266 } 267 268 return (res_nupdate(&_res, rrecp_in, NULL)); 269 } 270 #endif 271 272 int 273 res_search(const char *name, /* domain name */ 274 int class, int type, /* class and type of query */ 275 u_char *answer, /* buffer to put answer */ 276 int anslen) /* size of answer */ 277 { 278 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 279 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 280 return (-1); 281 } 282 283 return (res_nsearch(&_res, name, class, type, answer, anslen)); 284 } 285 286 int 287 res_querydomain(const char *name, 288 const char *domain, 289 int class, int type, /* class and type of query */ 290 u_char *answer, /* buffer to put answer */ 291 int anslen) /* size of answer */ 292 { 293 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 294 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 295 return (-1); 296 } 297 298 return (res_nquerydomain(&_res, name, domain, 299 class, type, 300 answer, anslen)); 301 } 302 303 int 304 res_opt(int a, u_char *b, int c, int d) 305 { 306 return res_nopt(&_res, a, b, c, d); 307 } 308 309 const char * 310 hostalias(const char *name) { 311 static char abuf[MAXDNAME]; 312 313 return (res_hostalias(&_res, name, abuf, sizeof abuf)); 314 } 315 316 #ifdef ultrix 317 int 318 local_hostname_length(const char *hostname) { 319 int len_host, len_domain; 320 321 if (!*_res.defdname) 322 res_init(); 323 len_host = strlen(hostname); 324 len_domain = strlen(_res.defdname); 325 if (len_host > len_domain && 326 !strcasecmp(hostname + len_host - len_domain, _res.defdname) && 327 hostname[len_host - len_domain - 1] == '.') 328 return (len_host - len_domain - 1); 329 return (0); 330 } 331 #endif /*ultrix*/ 332 333 #endif 334