res_data.c revision 156952
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 1.1.206.2 2004/03/16 12:34:18 marka Exp $"; 20#endif /* LIBC_SCCS and not lint */ 21 22#include "port_before.h" 23 24#include <sys/types.h> 25#include <sys/param.h> 26#include <sys/socket.h> 27#include <sys/time.h> 28 29#include <netinet/in.h> 30#include <arpa/inet.h> 31#include <arpa/nameser.h> 32 33#include <ctype.h> 34#include <netdb.h> 35#include <resolv.h> 36#include <res_update.h> 37#include <stdio.h> 38#include <stdlib.h> 39#include <string.h> 40#include <unistd.h> 41 42#include "port_after.h" 43#undef _res 44 45const char *_res_opcodes[] = { 46 "QUERY", 47 "IQUERY", 48 "CQUERYM", 49 "CQUERYU", /* experimental */ 50 "NOTIFY", /* experimental */ 51 "UPDATE", 52 "6", 53 "7", 54 "8", 55 "9", 56 "10", 57 "11", 58 "12", 59 "13", 60 "ZONEINIT", 61 "ZONEREF", 62}; 63 64#ifdef BIND_UPDATE 65const char *_res_sectioncodes[] = { 66 "ZONE", 67 "PREREQUISITES", 68 "UPDATE", 69 "ADDITIONAL", 70}; 71#endif 72 73#ifndef __BIND_NOSTATIC 74struct __res_state _res 75# if defined(__BIND_RES_TEXT) 76 = { RES_TIMEOUT, } /* Motorola, et al. */ 77# endif 78 ; 79 80/* Proto. */ 81 82int res_ourserver_p(const res_state, const struct sockaddr_in *); 83 84int 85res_init(void) { 86 extern int __res_vinit(res_state, int); 87 88 /* 89 * These three fields used to be statically initialized. This made 90 * it hard to use this code in a shared library. It is necessary, 91 * now that we're doing dynamic initialization here, that we preserve 92 * the old semantics: if an application modifies one of these three 93 * fields of _res before res_init() is called, res_init() will not 94 * alter them. Of course, if an application is setting them to 95 * _zero_ before calling res_init(), hoping to override what used 96 * to be the static default, we can't detect it and unexpected results 97 * will follow. Zero for any of these fields would make no sense, 98 * so one can safely assume that the applications were already getting 99 * unexpected results. 100 * 101 * _res.options is tricky since some apps were known to diddle the bits 102 * before res_init() was first called. We can't replicate that semantic 103 * with dynamic initialization (they may have turned bits off that are 104 * set in RES_DEFAULT). Our solution is to declare such applications 105 * "broken". They could fool us by setting RES_INIT but none do (yet). 106 */ 107 if (!_res.retrans) 108 _res.retrans = RES_TIMEOUT; 109 if (!_res.retry) 110 _res.retry = 4; 111 if (!(_res.options & RES_INIT)) 112 _res.options = RES_DEFAULT; 113 114 /* 115 * This one used to initialize implicitly to zero, so unless the app 116 * has set it to something in particular, we can randomize it now. 117 */ 118 if (!_res.id) 119 _res.id = res_randomid(); 120 121 return (__res_vinit(&_res, 1)); 122} 123 124void 125p_query(const u_char *msg) { 126 fp_query(msg, stdout); 127} 128 129void 130fp_query(const u_char *msg, FILE *file) { 131 fp_nquery(msg, PACKETSZ, file); 132} 133 134void 135fp_nquery(const u_char *msg, int len, FILE *file) { 136 if ((_res.options & RES_INIT) == 0U && res_init() == -1) 137 return; 138 139 res_pquery(&_res, msg, len, file); 140} 141 142int 143res_mkquery(int op, /* opcode of query */ 144 const char *dname, /* domain name */ 145 int class, int type, /* class and type of query */ 146 const u_char *data, /* resource record data */ 147 int datalen, /* length of data */ 148 const u_char *newrr_in, /* new rr for modify or append */ 149 u_char *buf, /* buffer to put query */ 150 int buflen) /* size of buffer */ 151{ 152 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 153 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 154 return (-1); 155 } 156 return (res_nmkquery(&_res, op, dname, class, type, 157 data, datalen, 158 newrr_in, buf, buflen)); 159} 160 161int 162res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) { 163 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 164 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 165 return (-1); 166 } 167 168 return (res_nmkupdate(&_res, rrecp_in, buf, buflen)); 169} 170 171int 172res_query(const char *name, /* domain name */ 173 int class, int type, /* class and type of query */ 174 u_char *answer, /* buffer to put answer */ 175 int anslen) /* size of answer buffer */ 176{ 177 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 178 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL); 179 return (-1); 180 } 181 return (res_nquery(&_res, name, class, type, answer, anslen)); 182} 183 184void 185res_send_setqhook(res_send_qhook hook) { 186 _res.qhook = hook; 187} 188 189void 190res_send_setrhook(res_send_rhook hook) { 191 _res.rhook = hook; 192} 193 194int 195res_isourserver(const struct sockaddr_in *inp) { 196 return (res_ourserver_p(&_res, inp)); 197} 198 199int 200res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) { 201 if ((_res.options & RES_INIT) == 0U && res_init() == -1) { 202 /* errno should have been set by res_init() in this case. */ 203 return (-1); 204 } 205 206 return (res_nsend(&_res, buf, buflen, ans, anssiz)); 207} 208 209int 210res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key, 211 u_char *ans, int anssiz) 212{ 213 if ((_res.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(&_res, buf, buflen, key, ans, anssiz)); 219} 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 267const char * 268hostalias(const char *name) { 269 static char abuf[MAXDNAME]; 270 271 return (res_hostalias(&_res, name, abuf, sizeof abuf)); 272} 273 274#ifdef ultrix 275int 276local_hostname_length(const char *hostname) { 277 int len_host, len_domain; 278 279 if (!*_res.defdname) 280 res_init(); 281 len_host = strlen(hostname); 282 len_domain = strlen(_res.defdname); 283 if (len_host > len_domain && 284 !strcasecmp(hostname + len_host - len_domain, _res.defdname) && 285 hostname[len_host - len_domain - 1] == '.') 286 return (len_host - len_domain - 1); 287 return (0); 288} 289#endif /*ultrix*/ 290 291#endif 292