1 /* $NetBSD: res_data.c,v 1.1.1.1 2009/04/12 15:33:57 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 #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 24 #include "port_before.h" 25 26 #include <sys/types.h> 27 #include <sys/param.h> 28 #include <sys/socket.h> 29 #include <sys/time.h> 30 31 #include <netinet/in.h> 32 #include <arpa/inet.h> 33 #include <arpa/nameser.h> 34 35 #include <ctype.h> 36 #include <netdb.h> 37 #include <resolv.h> 38 #include <res_update.h> 39 #include <stdio.h> 40 #include <stdlib.h> 41 #include <string.h> 42 #include <unistd.h> 43 44 #include "port_after.h" 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 struct __res_state _res 77 # if defined(__BIND_RES_TEXT) 78 = { RES_TIMEOUT, } /*%< Motorola, et al. */ 79 # endif 80 ; 81 82 #if defined(DO_PTHREADS) || defined(__linux) 83 #define _res (*__res_state()) 84 #endif 85 86 /* Proto. */ 87 88 int res_ourserver_p(const res_state, const struct sockaddr_in *); 89 90 int 91 res_init(void) { 92 extern int __res_vinit(res_state, int); 93 94 /* 95 * These three fields used to be statically initialized. This made 96 * it hard to use this code in a shared library. It is necessary, 97 * now that we're doing dynamic initialization here, that we preserve 98 * the old semantics: if an application modifies one of these three 99 * fields of _res before res_init() is called, res_init() will not 100 * alter them. Of course, if an application is setting them to 101 * _zero_ before calling res_init(), hoping to override what used 102 * to be the static default, we can't detect it and unexpected results 103 * will follow. Zero for any of these fields would make no sense, 104 * so one can safely assume that the applications were already getting 105 * unexpected results. 106 * 107 * _res.options is tricky since some apps were known to diddle the bits 108 * before res_init() was first called. We can't replicate that semantic 109 * with dynamic initialization (they may have turned bits off that are 110 * set in RES_DEFAULT). Our solution is to declare such applications 111 * "broken". They could fool us by setting RES_INIT but none do (yet). 112 */ 113 if (!_res.retrans) 114 _res.retrans = RES_TIMEOUT; 115 if (!_res.retry) 116 _res.retry = 4; 117 if (!(_res.options & RES_INIT)) 118 _res.options = RES_DEFAULT; 119 120 /* 121 * This one used to initialize implicitly to zero, so unless the app 122 * has set it to something in particular, we can randomize it now. 123 */ 124 if (!_res.id) 125 _res.id = res_nrandomid(&_res); 126 127 return (__res_vinit(&_res, 1)); 128 } 129 130 void 131 p_query(const u_char *msg) { 132 fp_query(msg, stdout); 133 } 134 135 void 136 fp_query(const u_char *msg, FILE *file) { 137 fp_nquery(msg, PACKETSZ, file); 138 } 139 140 void 141 fp_nquery(const u_char *msg, int len, FILE *file) { 142 if ((_res.options & RES_INIT) == 0U && res_init() == -1) 143 return; 144 145 res_pquery(&_res, msg, len, file); 146 } 147 148 int 149 res_mkquery(int op, /*!< opcode of query */ 150 const char *dname, /*!< domain name */ 151 int class, int type, /*!< class and type of query */ 152 const u_char *data, /*!< resource record data */ 153 int datalen, /*!< length of data */ 154 const u_char *newrr_in, /*!< new rr for modify or append */ 155 u_char *buf, /*!< buffer to put query */ 156 int buflen) /*!< size of buffer */ 157 { 158 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 159 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 160 return (-1); 161 } 162 return (res_nmkquery(&_res, op, dname, class, type, 163 data, datalen, 164 newrr_in, buf, buflen)); 165 } 166 167 int 168 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { 169 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 170 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 171 return (-1); 172 } 173 174 return (res_nmkupdate(&_res, rrecp_in, buf, buflen)); 175 } 176 177 int 178 res_query(const char *name, /*!< domain name */ 179 int class, int type, /*!< class and type of query */ 180 u_char *answer, /*!< buffer to put answer */ 181 int anslen) /*!< size of answer buffer */ 182 { 183 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 184 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 185 return (-1); 186 } 187 return (res_nquery(&_res, name, class, type, answer, anslen)); 188 } 189 190 void 191 res_send_setqhook(res_send_qhook hook) { 192 _res.qhook = hook; 193 } 194 195 void 196 res_send_setrhook(res_send_rhook hook) { 197 _res.rhook = hook; 198 } 199 200 int 201 res_isourserver(const struct sockaddr_in *inp) { 202 return (res_ourserver_p(&_res, inp)); 203 } 204 205 int 206 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { 207 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 208 /* errno should have been set by res_init() in this case. */ 209 return (-1); 210 } 211 212 return (res_nsend(&_res, buf, buflen, ans, anssiz)); 213 } 214 215 int 216 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, 217 u_char *ans, int anssiz) 218 { 219 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 220 /* errno should have been set by res_init() in this case. */ 221 return (-1); 222 } 223 224 return (res_nsendsigned(&_res, buf, buflen, key, ans, anssiz)); 225 } 226 227 void 228 res_close(void) { 229 res_nclose(&_res); 230 } 231 232 int 233 res_update(ns_updrec *rrecp_in) { 234 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 235 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 236 return (-1); 237 } 238 239 return (res_nupdate(&_res, rrecp_in, NULL)); 240 } 241 242 int 243 res_search(const char *name, /*!< domain name */ 244 int class, int type, /*!< class and type of query */ 245 u_char *answer, /*!< buffer to put answer */ 246 int anslen) /*!< size of answer */ 247 { 248 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 249 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 250 return (-1); 251 } 252 253 return (res_nsearch(&_res, name, class, type, answer, anslen)); 254 } 255 256 int 257 res_querydomain(const char *name, 258 const char *domain, 259 int class, int type, /*!< class and type of query */ 260 u_char *answer, /*!< buffer to put answer */ 261 int anslen) /*!< size of answer */ 262 { 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_nquerydomain(&_res, name, domain, 269 class, type, 270 answer, anslen)); 271 } 272 273 u_int 274 res_randomid(void) { 275 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 276 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 277 return (-1); 278 } 279 280 return (res_nrandomid(&_res)); 281 } 282 283 const char * 284 hostalias(const char *name) { 285 static char abuf[MAXDNAME]; 286 287 return (res_hostalias(&_res, name, abuf, sizeof abuf)); 288 } 289 290 #ifdef ultrix 291 int 292 local_hostname_length(const char *hostname) { 293 int len_host, len_domain; 294 295 if (!*_res.defdname) 296 res_init(); 297 len_host = strlen(hostname); 298 len_domain = strlen(_res.defdname); 299 if (len_host > len_domain && 300 !strcasecmp(hostname + len_host - len_domain, _res.defdname) && 301 hostname[len_host - len_domain - 1] == '.') 302 return (len_host - len_domain - 1); 303 return (0); 304 } 305 #endif /*ultrix*/ 306 307 #endif 308 309 /*! \file */ 310