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
  44 const char *_res_opcodes[] = {
  45         "QUERY",
  46         "IQUERY",
  47         "CQUERYM",
  48         "CQUERYU",      /*%< experimental */
  49         "NOTIFY",       /*%< experimental */
  50         "UPDATE",
  51         "6",
  52         "7",
  53         "8",
  54         "9",
  55         "10",
  56         "11",
  57         "12",
  58         "13",
  59         "ZONEINIT",
  60         "ZONEREF",
  61 };
  62
  63 #ifdef BIND_UPDATE
  64 const char *_res_sectioncodes[] = {
  65         "ZONE",
  66         "PREREQUISITES",
  67         "UPDATE",
  68         "ADDITIONAL",
  69 };
  70 #endif
  71
  72 #undef _res
  73 #ifndef __BIND_NOSTATIC
  74 struct __res_state _res
  75 # if defined(__BIND_RES_TEXT)
  76         = { RES_TIMEOUT, }      /*%< Motorola, et al. */
  77 # endif
  78         ;
  79
  80 #if defined(DO_PTHREADS) || defined(__linux)
  81 #define _res (*__res_state())
  82 #endif
  83
  84 /* Proto. */
  85
  86 int  res_ourserver_p(const res_state, const struct sockaddr_in *);
  87
  88 int
  89 res_init(void) {
  90         extern int __res_vinit(res_state, int);
  91
  92         /*
  93          * These three fields used to be statically initialized.  This made
  94          * it hard to use this code in a shared library.  It is necessary,
  95          * now that we're doing dynamic initialization here, that we preserve
  96          * the old semantics: if an application modifies one of these three
  97          * fields of _res before res_init() is called, res_init() will not
  98          * alter them.  Of course, if an application is setting them to
  99          * _zero_ before calling res_init(), hoping to override what used
 100          * to be the static default, we can't detect it and unexpected results
 101          * will follow.  Zero for any of these fields would make no sense,
 102          * so one can safely assume that the applications were already getting
 103          * unexpected results.
 104          *
 105          * _res.options is tricky since some apps were known to diddle the bits
 106          * before res_init() was first called. We can't replicate that semantic
 107          * with dynamic initialization (they may have turned bits off that are
 108          * set in RES_DEFAULT).  Our solution is to declare such applications
 109          * "broken".  They could fool us by setting RES_INIT but none do (yet).
 110          */
 111         if (!_res.retrans)
 112                 _res.retrans = RES_TIMEOUT;
 113         if (!_res.retry)
 114                 _res.retry = 4;
 115         if (!(_res.options & RES_INIT))
 116                 _res.options = RES_DEFAULT;
 117
 118         /*
 119          * This one used to initialize implicitly to zero, so unless the app
 120          * has set it to something in particular, we can randomize it now.
 121          */
 122         if (!_res.id)
 123                 _res.id = res_randomid();
 124
 125         return (__res_vinit(&_res, 1));
 126 }
 127
 128 void
 129 p_query(const u_char *msg) {
 130         fp_query(msg, stdout);
 131 }
 132
 133 void
 134 fp_query(const u_char *msg, FILE *file) {
 135         fp_nquery(msg, PACKETSZ, file);
 136 }
 137
 138 void
 139 fp_nquery(const u_char *msg, int len, FILE *file) {
 140         if ((_res.options & RES_INIT) == 0U && res_init() == -1)
 141                 return;
 142
 143         res_pquery(&_res, msg, len, file);
 144 }
 145
 146 int
 147 res_mkquery(int op,                     /*!< opcode of query  */
 148             const char *dname,          /*!< domain name  */
 149             int class, int type,        /*!< class and type of query  */
 150             const u_char *data,         /*!< resource record data  */
 151             int datalen,                /*!< length of data  */
 152             const u_char *newrr_in,     /*!< new rr for modify or append  */
 153             u_char *buf,                /*!< buffer to put query  */
 154             int buflen)                 /*!< size of buffer  */
 155 {
 156         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 157                 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 158                 return (-1);
 159         }
 160         return (res_nmkquery(&_res, op, dname, class, type,
 161                              data, datalen,
 162                              newrr_in, buf, buflen));
 163 }
 164
 165 int
 166 res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
 167         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 168                 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 169                 return (-1);
 170         }
 171
 172         return (res_nmkupdate(&_res, rrecp_in, buf, buflen));
 173 }
 174
 175 int
 176 res_query(const char *name,     /*!< domain name  */
 177           int class, int type,  /*!< class and type of query  */
 178           u_char *answer,       /*!< buffer to put answer  */
 179           int anslen)           /*!< size of answer buffer  */
 180 {
 181         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 182                 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 183                 return (-1);
 184         }
 185         return (res_nquery(&_res, name, class, type, answer, anslen));
 186 }
 187
 188 void
 189 res_send_setqhook(res_send_qhook hook) {
 190         _res.qhook = hook;
 191 }
 192
 193 void
 194 res_send_setrhook(res_send_rhook hook) {
 195         _res.rhook = hook;
 196 }
 197
 198 int
 199 res_isourserver(const struct sockaddr_in *inp) {
 200         return (res_ourserver_p(&_res, inp));
 201 }
 202
 203 int
 204 res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) {
 205         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 206                 /* errno should have been set by res_init() in this case. */
 207                 return (-1);
 208         }
 209
 210         return (res_nsend(&_res, buf, buflen, ans, anssiz));
 211 }
 212
 213 int
 214 res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key,
 215                u_char *ans, int anssiz)
 216 {
 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_nsendsigned(&_res, buf, buflen, key, ans, anssiz));
 223 }
 224
 225 void
 226 res_close(void) {
 227         res_nclose(&_res);
 228 }
 229
 230 int
 231 res_update(ns_updrec *rrecp_in) {
 232         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 233                 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 234                 return (-1);
 235         }
 236
 237         return (res_nupdate(&_res, rrecp_in, NULL));
 238 }
 239
 240 int
 241 res_search(const char *name,    /*!< domain name  */
 242            int class, int type, /*!< class and type of query  */
 243            u_char *answer,      /*!< buffer to put answer  */
 244            int anslen)          /*!< size of answer  */
 245 {
 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_nsearch(&_res, name, class, type, answer, anslen));
 252 }
 253
 254 int
 255 res_querydomain(const char *name,
 256                 const char *domain,
 257                 int class, int type,    /*!< class and type of query  */
 258                 u_char *answer,         /*!< buffer to put answer  */
 259                 int anslen)             /*!< size of answer  */
 260 {
 261         if ((_res.options & RES_INIT) == 0U && res_init() == -1) {
 262                 RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
 263                 return (-1);
 264         }
 265
 266         return (res_nquerydomain(&_res, name, domain,
 267                                  class, type,
 268                                  answer, anslen));
 269 }
 270
 271 const char *
 272 hostalias(const char *name) {
 273         static char abuf[MAXDNAME];
 274
 275         return (res_hostalias(&_res, name, abuf, sizeof abuf));
 276 }
 277
 278 #ifdef ultrix
 279 int
 280 local_hostname_length(const char *hostname) {
 281         int len_host, len_domain;
 282
 283         if (!*_res.defdname)
 284                 res_init();
 285         len_host = strlen(hostname);
 286         len_domain = strlen(_res.defdname);
 287         if (len_host > len_domain &&
 288             !strcasecmp(hostname + len_host - len_domain, _res.defdname) &&
 289             hostname[len_host - len_domain - 1] == '.')
 290                 return (len_host - len_domain - 1);
 291         return (0);
 292 }
 293 #endif /*ultrix*/
 294
 295 #endif
 296
 297 /*! \file */