contrib/bind-9.5.2/lib/bind/resolv/res_data.c

   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)
  19 static const char rcsid[] = "$Id: res_data.c,v 1.5 2007/09/14 05:32:25 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 #ifndef _LIBC
  44 #undef _res
  45 #endif
  46
  47
  48 const char *_res_opcodes[] = {
  49         "QUERY",
  50         "IQUERY",
  51         "CQUERYM",
  52         "CQUERYU",      /*%< experimental */
  53         "NOTIFY",       /*%< experimental */
  54         "UPDATE",
  55         "6",
  56         "7",
  57         "8",
  58         "9",
  59         "10",
  60         "11",
  61         "12",
  62         "13",
  63         "ZONEINIT",
  64         "ZONEREF",
  65 };
  66
  67 #ifdef BIND_UPDATE
  68 const char *_res_sectioncodes[] = {
  69         "ZONE",
  70         "PREREQUISITES",
  71         "UPDATE",
  72         "ADDITIONAL",
  73 };
  74 #endif
  75
  76 #undef _res
  77 #ifndef __BIND_NOSTATIC
  78 #ifndef _LIBC
  79 struct __res_state _res
  80 # if defined(__BIND_RES_TEXT)
  81         = { RES_TIMEOUT, }      /*%< Motorola, et al. */
  82 # endif
  83         ;
  84 #endif /* !_LIBC */
  85
  86 #if defined(DO_PTHREADS) || defined(__linux)
  87 #define _res (*__res_state())
  88 #endif
  89
  90 /* Proto. */
  91
  92 int  res_ourserver_p(const res_state, const struct sockaddr_in *);
  93
  94 int
  95 res_init(void) {
  96         extern int __res_vinit(res_state, int);
  97
  98         /*
  99          * These three fields used to be statically initialized.  This made
 100          * it hard to use this code in a shared library.  It is necessary,
 101          * now that we're doing dynamic initialization here, that we preserve
 102          * the old semantics: if an application modifies one of these three
 103          * fields of _res before res_init() is called, res_init() will not
 104          * alter them.  Of course, if an application is setting them to
 105          * _zero_ before calling res_init(), hoping to override what used
 106          * to be the static default, we can't detect it and unexpected results
 107          * will follow.  Zero for any of these fields would make no sense,
 108          * so one can safely assume that the applications were already getting
 109          * unexpected results.
 110          *
 111          * _res.options is tricky since some apps were known to diddle the bits
 112          * before res_init() was first called. We can't replicate that semantic
 113          * with dynamic initialization (they may have turned bits off that are
 114          * set in RES_DEFAULT).  Our solution is to declare such applications
 115          * "broken".  They could fool us by setting RES_INIT but none do (yet).
 116          */
 117         if (!_res.retrans)
 118                 _res.retrans = RES_TIMEOUT;
 119         if (!_res.retry)
 120 #ifndef _LIBC
 121                 _res.retry = 4;
 122 #else
 123                 _res.retry = RES_DFLRETRY;
 124 #endif
 125         if (!(_res.options & RES_INIT))
 126                 _res.options = RES_DEFAULT;
 127
 128         /*
 129          * This one used to initialize implicitly to zero, so unless the app
 130          * has set it to something in particular, we can randomize it now.
 131          */
 132         if (!_res.id)
 133                 _res.id = res_randomid();
 134
 135         return (__res_vinit(&_res, 1));
 136 }
 137
 138 void
 139 p_query(const u_char *msg) {
 140         fp_query(msg, stdout);
 141 }
 142
 143 void
 144 fp_query(const u_char *msg, FILE *file) {
 145         fp_nquery(msg, PACKETSZ, file);
 146 }
 147
 148 void
 149 fp_nquery(const u_char *msg, int len, FILE *file) {
 150         if ((_res.options & RES_INIT) == 0U && res_init() == -1)
 151                 return;
 152
 153         res_pquery(&_res, msg, len, file);
 154 }
 155
 156 int
 157 res_mkquery(int op,                     /*!< opcode of query  */
 158             const char *dname,          /*!< domain name  */
 159             int class, int type,        /*!< class and type of query  */
 160             const u_char *data,         /*!< resource record data  */
 161             int datalen,                /*!< length of data  */
 162             const u_char *newrr_in,     /*!< new rr for modify or append  */
 163             u_char *buf,                /*!< buffer to put query  */
 164             int buflen)                 /*!< size of buffer  */
 165 {
 166         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 167                 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 168                 return (-1);
 169         }
 170         return (res_nmkquery(&_res, op, dname, class, type,
 171                              data, datalen,
 172                              newrr_in, buf, buflen));
 173 }
 174
 175 int
 176 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
 177         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 178                 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 179                 return (-1);
 180         }
 181
 182         return (res_nmkupdate(&_res, rrecp_in, buf, buflen));
 183 }
 184
 185 int
 186 res_query(const char *name,     /*!< domain name  */
 187           int class, int type,  /*!< class and type of query  */
 188           u_char *answer,       /*!< buffer to put answer  */
 189           int anslen)           /*!< size of answer buffer  */
 190 {
 191         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 192                 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 193                 return (-1);
 194         }
 195         return (res_nquery(&_res, name, class, type, answer, anslen));
 196 }
 197
 198 #ifndef _LIBC
 199 void
 200 res_send_setqhook(res_send_qhook hook) {
 201         _res.qhook = hook;
 202 }
 203
 204 void
 205 res_send_setrhook(res_send_rhook hook) {
 206         _res.rhook = hook;
 207 }
 208 #endif
 209
 210 int
 211 res_isourserver(const struct sockaddr_in *inp) {
 212         return (res_ourserver_p(&_res, inp));
 213 }
 214
 215 int
 216 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) {
 217         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 218                 /* errno should have been set by res_init() in this case. */
 219                 return (-1);
 220         }
 221
 222         return (res_nsend(&_res, buf, buflen, ans, anssiz));
 223 }
 224
 225 #ifndef _LIBC
 226 int
 227 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key,
 228                u_char *ans, int anssiz)
 229 {
 230         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 231                 /* errno should have been set by res_init() in this case. */
 232                 return (-1);
 233         }
 234
 235         return (res_nsendsigned(&_res, buf, buflen, key, ans, anssiz));
 236 }
 237 #endif
 238
 239 void
 240 res_close(void) {
 241         res_nclose(&_res);
 242 }
 243
 244 int
 245 res_update(ns_updrec *rrecp_in) {
 246         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 247                 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 248                 return (-1);
 249         }
 250
 251         return (res_nupdate(&_res, rrecp_in, NULL));
 252 }
 253
 254 int
 255 res_search(const char *name,    /*!< domain name  */
 256            int class, int type, /*!< class and type of query  */
 257            u_char *answer,      /*!< buffer to put answer  */
 258            int anslen)          /*!< size of answer  */
 259 {
 260         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 261                 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 262                 return (-1);
 263         }
 264
 265         return (res_nsearch(&_res, name, class, type, answer, anslen));
 266 }
 267
 268 int
 269 res_querydomain(const char *name,
 270                 const char *domain,
 271                 int class, int type,    /*!< class and type of query  */
 272                 u_char *answer,         /*!< buffer to put answer  */
 273                 int anslen)             /*!< size of answer  */
 274 {
 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_nquerydomain(&_res, name, domain,
 281                                  class, type,
 282                                  answer, anslen));
 283 }
 284
 285 #ifdef _LIBC
 286 int
 287 res_opt(int n0, u_char *buf, int buflen, int anslen)
 288 {
 289        return (res_nopt(&_res, n0, buf, buflen, anslen));
 290 }
 291 #endif
 292
 293 const char *
 294 hostalias(const char *name) {
 295         static char abuf[MAXDNAME];
 296
 297         return (res_hostalias(&_res, name, abuf, sizeof abuf));
 298 }
 299
 300 #ifdef ultrix
 301 int
 302 local_hostname_length(const char *hostname) {
 303         int len_host, len_domain;
 304
 305         if (!*_res.defdname)
 306                 res_init();
 307         len_host = strlen(hostname);
 308         len_domain = strlen(_res.defdname);
 309         if (len_host > len_domain &&
 310             !strcasecmp(hostname + len_host - len_domain, _res.defdname) &&
 311             hostname[len_host - len_domain - 1] == '.')
 312                 return (len_host - len_domain - 1);
 313         return (0);
 314 }
 315 #endif /*ultrix*/
 316
 317 #ifdef _LIBC
 318 /*
 319  * Weak aliases for applications that use certain private entry points,
 320  * and fail to include <resolv.h>.
 321  */
 322 #undef res_init
 323 __weak_reference(__res_init, res_init);
 324 #undef p_query
 325 __weak_reference(__p_query, p_query);
 326 #undef res_mkquery
 327 __weak_reference(__res_mkquery, res_mkquery);
 328 #undef res_query
 329 __weak_reference(__res_query, res_query);
 330 #undef res_send
 331 __weak_reference(__res_send, res_send);
 332 #undef res_close
 333 __weak_reference(__res_close, _res_close);
 334 #undef res_search
 335 __weak_reference(__res_search, res_search);
 336 #undef res_querydomain
 337 __weak_reference(__res_querydomain, res_querydomain);
 338 #endif
 339
 340 #endif
 341 /*! \file */