1 /* $NetBSD: res_data.c,v 1.8 2004/06/09 18:07:03 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 1.8 2004/06/09 18:07:03 christos Exp $"); 26 #endif 27 #endif /* LIBC_SCCS and not lint */ 28 29 30 31 #include <sys/types.h> 32 #include <sys/param.h> 33 #include <sys/socket.h> 34 #include <sys/time.h> 35 36 #include <netinet/in.h> 37 #include <arpa/inet.h> 38 #include <arpa/nameser.h> 39 40 #include <ctype.h> 41 #include <netdb.h> 42 #include "resolv_private.h" 43 #include <stdio.h> 44 #include <stdlib.h> 45 #include <string.h> 46 #include <unistd.h> 47 48 49 __LIBC_HIDDEN__ 50 const char * const _res_opcodes[] = { 51 "QUERY", 52 "IQUERY", 53 "CQUERYM", 54 "CQUERYU", /* experimental */ 55 "NOTIFY", /* experimental */ 56 "UPDATE", 57 "6", 58 "7", 59 "8", 60 "9", 61 "10", 62 "11", 63 "12", 64 "13", 65 "ZONEINIT", 66 "ZONEREF", 67 }; 68 69 #ifdef BIND_UPDATE 70 const char * const _res_sectioncodes[] = { 71 "ZONE", 72 "PREREQUISITES", 73 "UPDATE", 74 "ADDITIONAL", 75 }; 76 #endif 77 78 #ifndef __BIND_NOSTATIC 79 extern struct __res_state _nres; 80 81 /* Proto. */ 82 83 int res_ourserver_p(const res_state, const struct sockaddr *); 84 85 #define res_need_init() ((_nres.options & RES_INIT) == 0U) 86 87 int 88 res_init(void) { 89 int rv; 90 extern int __res_vinit(res_state, int); 91 #ifdef COMPAT__RES 92 /* 93 * Compatibility with program that were accessing _res directly 94 * to set options. We keep another struct res that is the same 95 * size as the original res structure, and then copy fields to 96 * it so that we achieve the same initialization 97 */ 98 extern void *__res_get_old_state(void); 99 extern void __res_put_old_state(void *); 100 res_state ores = __res_get_old_state(); 101 102 if (ores->options != 0) 103 _nres.options = ores->options; 104 if (ores->retrans != 0) 105 _nres.retrans = ores->retrans; 106 if (ores->retry != 0) 107 _nres.retry = ores->retry; 108 #endif 109 110 /* 111 * These three fields used to be statically initialized. This made 112 * it hard to use this code in a shared library. It is necessary, 113 * now that we're doing dynamic initialization here, that we preserve 114 * the old semantics: if an application modifies one of these three 115 * fields of _res before res_init() is called, res_init() will not 116 * alter them. Of course, if an application is setting them to 117 * _zero_ before calling res_init(), hoping to override what used 118 * to be the static default, we can't detect it and unexpected results 119 * will follow. Zero for any of these fields would make no sense, 120 * so one can safely assume that the applications were already getting 121 * unexpected results. 122 * 123 * _nres.options is tricky since some apps were known to diddle the bits 124 * before res_init() was first called. We can't replicate that semantic 125 * with dynamic initialization (they may have turned bits off that are 126 * set in RES_DEFAULT). Our solution is to declare such applications 127 * "broken". They could fool us by setting RES_INIT but none do (yet). 128 */ 129 if (!_nres.retrans) 130 _nres.retrans = RES_TIMEOUT; 131 if (!_nres.retry) 132 _nres.retry = 4; 133 if (!(_nres.options & RES_INIT)) 134 _nres.options = RES_DEFAULT; 135 136 /* 137 * This one used to initialize implicitly to zero, so unless the app 138 * has set it to something in particular, we can randomize it now. 139 */ 140 if (!_nres.id) 141 _nres.id = res_randomid(); 142 143 rv = __res_vinit(&_nres, 1); 144 #ifdef COMPAT__RES 145 __res_put_old_state(&_nres); 146 #endif 147 return rv; 148 } 149 150 void 151 p_query(const u_char *msg) { 152 fp_query(msg, stdout); 153 } 154 155 void 156 fp_query(const u_char *msg, FILE *file) { 157 fp_nquery(msg, PACKETSZ, file); 158 } 159 160 void 161 fp_nquery(const u_char *msg, int len, FILE *file) { 162 if (res_need_init() && res_init() == -1) 163 return; 164 165 res_pquery(&_nres, msg, len, file); 166 } 167 168 int 169 res_mkquery(int op, /* opcode of query */ 170 const char *dname, /* domain name */ 171 int class, int type, /* class and type of query */ 172 const u_char *data, /* resource record data */ 173 int datalen, /* length of data */ 174 const u_char *newrr_in, /* new rr for modify or append */ 175 u_char *buf, /* buffer to put query */ 176 int buflen) /* size of buffer */ 177 { 178 if (res_need_init() && res_init() == -1) { 179 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 180 return (-1); 181 } 182 return (res_nmkquery(&_nres, op, dname, class, type, 183 data, datalen, 184 newrr_in, buf, buflen)); 185 } 186 187 #ifdef _LIBRESOLV 188 int 189 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { 190 if (res_need_init() && res_init() == -1) { 191 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 192 return (-1); 193 } 194 195 return (res_nmkupdate(&_nres, rrecp_in, buf, buflen)); 196 } 197 #endif 198 199 int 200 res_query(const char *name, /* domain name */ 201 int class, int type, /* class and type of query */ 202 u_char *answer, /* buffer to put answer */ 203 int anslen) /* size of answer buffer */ 204 { 205 if (res_need_init() && res_init() == -1) { 206 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 207 return (-1); 208 } 209 return (res_nquery(&_nres, name, class, type, answer, anslen)); 210 } 211 212 void 213 res_send_setqhook(res_send_qhook hook) { 214 _nres.qhook = hook; 215 } 216 217 void 218 res_send_setrhook(res_send_rhook hook) { 219 _nres.rhook = hook; 220 } 221 222 int 223 res_isourserver(const struct sockaddr_in *inp) { 224 return (res_ourserver_p(&_nres, (const struct sockaddr *)(const void *)inp)); 225 } 226 227 int 228 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { 229 if (res_need_init() && res_init() == -1) { 230 /* errno should have been set by res_init() in this case. */ 231 return (-1); 232 } 233 234 return (res_nsend(&_nres, buf, buflen, ans, anssiz)); 235 } 236 237 #ifdef _LIBRESOLV 238 int 239 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, 240 u_char *ans, int anssiz) 241 { 242 if (res_need_init() && res_init() == -1) { 243 /* errno should have been set by res_init() in this case. */ 244 return (-1); 245 } 246 247 return (res_nsendsigned(&_nres, buf, buflen, key, ans, anssiz)); 248 } 249 #endif 250 251 void 252 res_close(void) { 253 res_nclose(&_nres); 254 } 255 256 #ifdef _LIBRESOLV 257 int 258 res_update(ns_updrec *rrecp_in) { 259 if (res_need_init() && res_init() == -1) { 260 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 261 return (-1); 262 } 263 264 return (res_nupdate(&_nres, rrecp_in, NULL)); 265 } 266 #endif 267 268 int 269 res_search(const char *name, /* domain name */ 270 int class, int type, /* class and type of query */ 271 u_char *answer, /* buffer to put answer */ 272 int anslen) /* size of answer */ 273 { 274 if (res_need_init() && res_init() == -1) { 275 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 276 return (-1); 277 } 278 279 return (res_nsearch(&_nres, name, class, type, answer, anslen)); 280 } 281 282 int 283 res_querydomain(const char *name, 284 const char *domain, 285 int class, int type, /* class and type of query */ 286 u_char *answer, /* buffer to put answer */ 287 int anslen) /* size of answer */ 288 { 289 if (res_need_init() && res_init() == -1) { 290 RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL); 291 return (-1); 292 } 293 294 return (res_nquerydomain(&_nres, name, domain, 295 class, type, 296 answer, anslen)); 297 } 298 299 int 300 res_opt(int a, u_char *b, int c, int d) 301 { 302 return res_nopt(&_nres, a, b, c, d); 303 } 304 305 const char * 306 hostalias(const char *name) { 307 return NULL; 308 } 309 310 #ifdef ultrix 311 int 312 local_hostname_length(const char *hostname) { 313 int len_host, len_domain; 314 315 if (!*_nres.defdname) 316 res_init(); 317 len_host = strlen(hostname); 318 len_domain = strlen(_nres.defdname); 319 if (len_host > len_domain && 320 !strcasecmp(hostname + len_host - len_domain, _nres.defdname) && 321 hostname[len_host - len_domain - 1] == '.') 322 return (len_host - len_domain - 1); 323 return (0); 324 } 325 #endif /*ultrix*/ 326 327 #endif 328
