res_data.c revision 170244
1/* 2 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC") 3 * Copyright (c) 1995-1999 by Internet Software Consortium. 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT 15 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18#if defined(LIBC_SCCS) && !defined(lint) 19static const char rcsid[] = "$Id: res_data.c,v 1.3.18.1 2005/04/27 05:01:10 sra Exp $"; 20#endif /* LIBC_SCCS and not lint */ 21#include <sys/cdefs.h> 22__FBSDID("$FreeBSD: head/lib/libc/resolv/res_data.c 170244 2007-06-03 17:20:27Z ume $"); 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 46const 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 66const char *_res_sectioncodes[] = { 67 "ZONE", 68 "PREREQUISITES", 69 "UPDATE", 70 "ADDITIONAL", 71}; 72#endif 73 74#ifndef __BIND_NOSTATIC 75 76/* Proto. */ 77 78int res_ourserver_p(const res_state, const struct sockaddr_in *); 79 80int 81res_init(void) { 82 extern int __res_vinit(res_state, int); 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 (!_res.retrans) 104 _res.retrans = RES_TIMEOUT; 105 if (!_res.retry) 106 _res.retry = RES_DFLRETRY; 107 if (!(_res.options & RES_INIT)) 108 _res.options = RES_DEFAULT; 109 110 /* 111 * This one used to initialize implicitly to zero, so unless the app 112 * has set it to something in particular, we can randomize it now. 113 */ 114 if (!_res.id) 115 _res.id = res_randomid(); 116 117 return (__res_vinit(&_res, 1)); 118} 119 120void 121p_query(const u_char *msg) { 122 fp_query(msg, stdout); 123} 124 125void 126fp_query(const u_char *msg, FILE *file) { 127 fp_nquery(msg, PACKETSZ, file); 128} 129 130void 131fp_nquery(const u_char *msg, int len, FILE *file) { 132 if ((_res.options & RES_INIT) == 0U && res_init() == -1) 133 return; 134 135 res_pquery(&_res, msg, len, file); 136} 137 138int 139res_mkquery(int op, /*!< opcode of query */ 140 const char *dname, /*!< domain name */ 141 int class, int type, /*!< class and type of query */ 142 const u_char *data, /*!< resource record data */ 143 int datalen, /*!< length of data */ 144 const u_char *newrr_in, /*!< new rr for modify or append */ 145 u_char *buf, /*!< buffer to put query */ 146 int buflen) /*!< size of buffer */ 147{ 148 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 149 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 150 return (-1); 151 } 152 return (res_nmkquery(&_res, op, dname, class, type, 153 data, datalen, 154 newrr_in, buf, buflen)); 155} 156 157int 158res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { 159 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 160 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 161 return (-1); 162 } 163 164 return (res_nmkupdate(&_res, rrecp_in, buf, buflen)); 165} 166 167int 168res_query(const char *name, /*!< domain name */ 169 int class, int type, /*!< class and type of query */ 170 u_char *answer, /*!< buffer to put answer */ 171 int anslen) /*!< size of answer buffer */ 172{ 173 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 174 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 175 return (-1); 176 } 177 return (res_nquery(&_res, name, class, type, answer, anslen)); 178} 179 180#ifndef _LIBC 181void 182res_send_setqhook(res_send_qhook hook) { 183 _res.qhook = hook; 184} 185 186void 187res_send_setrhook(res_send_rhook hook) { 188 _res.rhook = hook; 189} 190#endif 191 192int 193res_isourserver(const struct sockaddr_in *inp) { 194 return (res_ourserver_p(&_res, inp)); 195} 196 197int 198res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { 199 if ((_res.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(&_res, buf, buflen, ans, anssiz)); 205} 206 207#ifndef _LIBC 208int 209res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, 210 u_char *ans, int anssiz) 211{ 212 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 213 /* errno should have been set by res_init() in this case. */ 214 return (-1); 215 } 216 217 return (res_nsendsigned(&_res, buf, buflen, key, ans, anssiz)); 218} 219#endif 220 221void 222res_close(void) { 223 res_nclose(&_res); 224} 225 226int 227res_update(ns_updrec *rrecp_in) { 228 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 229 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 230 return (-1); 231 } 232 233 return (res_nupdate(&_res, rrecp_in, NULL)); 234} 235 236int 237res_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 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 243 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 244 return (-1); 245 } 246 247 return (res_nsearch(&_res, name, class, type, answer, anslen)); 248} 249 250int 251res_querydomain(const char *name, 252 const char *domain, 253 int class, int type, /*!< class and type of query */ 254 u_char *answer, /*!< buffer to put answer */ 255 int anslen) /*!< size of answer */ 256{ 257 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 258 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 259 return (-1); 260 } 261 262 return (res_nquerydomain(&_res, name, domain, 263 class, type, 264 answer, anslen)); 265} 266 267int 268res_opt(int n0, u_char *buf, int buflen, int anslen) 269{ 270 return (res_nopt(&_res, n0, buf, buflen, anslen)); 271} 272 273const char * 274hostalias(const char *name) { 275 static char abuf[MAXDNAME]; 276 277 return (res_hostalias(&_res, name, abuf, sizeof abuf)); 278} 279 280#ifdef ultrix 281int 282local_hostname_length(const char *hostname) { 283 int len_host, len_domain; 284 285 if (!*_res.defdname) 286 res_init(); 287 len_host = strlen(hostname); 288 len_domain = strlen(_res.defdname); 289 if (len_host > len_domain && 290 !strcasecmp(hostname + len_host - len_domain, _res.defdname) && 291 hostname[len_host - len_domain - 1] == '.') 292 return (len_host - len_domain - 1); 293 return (0); 294} 295#endif /*ultrix*/ 296 297/* 298 * Weak aliases for applications that use certain private entry points, 299 * and fail to include <resolv.h>. 300 */ 301#undef res_init 302__weak_reference(__res_init, res_init); 303#undef p_query 304__weak_reference(__p_query, p_query); 305#undef res_mkquery 306__weak_reference(__res_mkquery, res_mkquery); 307#undef res_query 308__weak_reference(__res_query, res_query); 309#undef res_send 310__weak_reference(__res_send, res_send); 311#undef res_close 312__weak_reference(__res_close, _res_close); 313#undef res_search 314__weak_reference(__res_search, res_search); 315#undef res_querydomain 316__weak_reference(__res_querydomain, res_querydomain); 317 318#endif 319 320/*! \file */ 321