resolv/resolv.h

   1 /*
   2  * ++Copyright++ 1983, 1987, 1989, 1993
   3  * -
   4  * Copyright (c) 1983, 1987, 1989, 1993
   5  *    The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 4. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  * -
  31  * Portions Copyright (c) 1993 by Digital Equipment Corporation.
  32  *
  33  * Permission to use, copy, modify, and distribute this software for any
  34  * purpose with or without fee is hereby granted, provided that the above
  35  * copyright notice and this permission notice appear in all copies, and that
  36  * the name of Digital Equipment Corporation not be used in advertising or
  37  * publicity pertaining to distribution of the document or software without
  38  * specific, written prior permission.
  39  *
  40  * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
  41  * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
  42  * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
  43  * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  44  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  45  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  46  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  47  * SOFTWARE.
  48  * -
  49  * --Copyright--
  50  */
  51
  52 /*
  53  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
  54  *
  55  * Permission to use, copy, modify, and distribute this software for any
  56  * purpose with or without fee is hereby granted, provided that the above
  57  * copyright notice and this permission notice appear in all copies.
  58  *
  59  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
  60  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  61  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  62  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  63  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  64  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  65  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  66  * SOFTWARE.
  67  */
  68
  69 /*
  70  *      @(#)resolv.h    8.1 (Berkeley) 6/2/93
  71  *      $Id$
  72  */
  73
  74 #ifndef _RESOLV_H
  75 #define _RESOLV_H 1
  76
  77 #include <features.h>
  78
  79 #include <sys/param.h>
  80 #if (!defined(BSD)) || (BSD < 199306)
  81 # include <sys/bitypes.h>
  82 #else
  83 # include <sys/types.h>
  84 #endif
  85 #include <stdio.h>
  86 #include <netinet/in.h>
  87
  88 /*
  89  * Revision information.  This is the release date in YYYYMMDD format.
  90  * It can change every day so the right thing to do with it is use it
  91  * in preprocessor commands such as "#if (__RES > 19931104)".  Do not
  92  * compare for equality; rather, use it to determine whether your resolver
  93  * is new enough to contain a certain feature.
  94  */
  95
  96 #define __RES   19991006
  97
  98 /*
  99  * This used to be defined in res_query.c, now it's in herror.c.
 100  * [XXX no it's not.  It's in irs/irs_data.c]
 101  * It was
 102  * never extern'd by any *.h file before it was placed here.  For thread
 103  * aware programs, the last h_errno value set is stored in res->h_errno.
 104  *
 105  * XXX: There doesn't seem to be a good reason for exposing RES_SET_H_ERRNO
 106  *      (and __h_errno_set) to the public via <resolv.h>.
 107  * XXX: __h_errno_set is really part of IRS, not part of the resolver.
 108  *      If somebody wants to build and use a resolver that doesn't use IRS,
 109  *      what do they do?  Perhaps something like
 110  *              #ifdef WANT_IRS
 111  *              # define RES_SET_H_ERRNO(r,x) __h_errno_set(r,x)
 112  *              #else
 113  *              # define RES_SET_H_ERRNO(r,x) (h_errno = (r)->res_h_errno = (x))
 114  *              #endif
 115  */
 116 #define RES_SET_H_ERRNO(r,x)                    \
 117   do                                            \
 118     {                                           \
 119       (r)->res_h_errno = x;                     \
 120       __set_h_errno(x);                         \
 121     }                                           \
 122   while (0)
 123
 124 struct __res_state; /* forward */
 125
 126 /*
 127  * Resolver configuration file.
 128  * Normally not present, but may contain the address of the
 129  * initial name server(s) to query and the domain search list.
 130  */
 131
 132 #ifndef _PATH_RESCONF
 133 #define _PATH_RESCONF        "/etc/resolv.conf"
 134 #endif
 135
 136 typedef enum { res_goahead, res_nextns, res_modified, res_done, res_error }
 137         res_sendhookact;
 138
 139 typedef res_sendhookact (*res_send_qhook) (struct sockaddr_in * const *ns,
 140                                            const u_char **query,
 141                                            int *querylen,
 142                                            u_char *ans,
 143                                            int anssiz,
 144                                            int *resplen);
 145
 146 typedef res_sendhookact (*res_send_rhook) (const struct sockaddr_in *ns,
 147                                            const u_char *query,
 148                                            int querylen,
 149                                            u_char *ans,
 150                                            int anssiz,
 151                                            int *resplen);
 152
 153 struct res_sym {
 154         int     number;         /* Identifying number, like T_MX */
 155         char *  name;           /* Its symbolic name, like "MX" */
 156         char *  humanname;      /* Its fun name, like "mail exchanger" */
 157 };
 158
 159 /*
 160  * Global defines and variables for resolver stub.
 161  */
 162 #define MAXNS                   3       /* max # name servers we'll track */
 163 #define MAXDFLSRCH              3       /* # default domain levels to try */
 164 #define MAXDNSRCH               6       /* max # domains in search path */
 165 #define LOCALDOMAINPARTS        2       /* min levels in name that is "local" */
 166
 167 #define RES_TIMEOUT             5       /* min. seconds between retries */
 168 #define MAXRESOLVSORT           10      /* number of net to sort on */
 169 #define RES_MAXNDOTS            15      /* should reflect bit field size */
 170 #define RES_MAXRETRANS          30      /* only for resolv.conf/RES_OPTIONS */
 171 #define RES_MAXRETRY            5       /* only for resolv.conf/RES_OPTIONS */
 172 #define RES_DFLRETRY            2       /* Default #/tries. */
 173
 174 struct __res_state {
 175         int     retrans;                /* retransmission time interval */
 176         int     retry;                  /* number of times to retransmit */
 177         u_long  options;                /* option flags - see below. */
 178         int     nscount;                /* number of name servers */
 179         struct sockaddr_in
 180                 nsaddr_list[MAXNS];     /* address of name server */
 181 #define nsaddr  nsaddr_list[0]          /* for backward compatibility */
 182         u_short id;                     /* current message id */
 183         char    *dnsrch[MAXDNSRCH+1];   /* components of domain to search */
 184         char    defdname[256];          /* default domain (deprecated) */
 185         u_long  pfcode;                 /* RES_PRF_ flags - see below. */
 186         unsigned ndots:4;               /* threshold for initial abs. query */
 187         unsigned nsort:4;               /* number of elements in sort_list[] */
 188         char    unused[3];
 189         struct {
 190                 struct in_addr  addr;
 191                 u_int32_t       mask;
 192         } sort_list[MAXRESOLVSORT];
 193         res_send_qhook qhook;           /* query hook */
 194         res_send_rhook rhook;           /* response hook */
 195         int     res_h_errno;            /* last one set for this context */
 196         int     _sock;                  /* PRIVATE: for res_send i/o */
 197         u_int   _flags;                 /* PRIVATE: see below */
 198         char    pad[52];                /* On an i386 this means 512b total. */
 199 };
 200
 201 typedef struct __res_state *res_state;
 202
 203 /*
 204  * Resolver flags (used to be discrete per-module statics ints).
 205  */
 206 #define RES_F_VC        0x00000001      /* socket is TCP */
 207 #define RES_F_CONN      0x00000002      /* socket is connected */
 208
 209 /* res_findzonecut() options */
 210 #define RES_EXHAUSTIVE  0x00000001      /* always do all queries */
 211
 212 /*
 213  * Resolver options (keep these in synch with res_debug.c, please)
 214  */
 215 #define RES_INIT        0x00000001      /* address initialized */
 216 #define RES_DEBUG       0x00000002      /* print debug messages */
 217 #define RES_AAONLY      0x00000004      /* authoritative answers only (!IMPL)*/
 218 #define RES_USEVC       0x00000008      /* use virtual circuit */
 219 #define RES_PRIMARY     0x00000010      /* query primary server only (!IMPL) */
 220 #define RES_IGNTC       0x00000020      /* ignore trucation errors */
 221 #define RES_RECURSE     0x00000040      /* recursion desired */
 222 #define RES_DEFNAMES    0x00000080      /* use default domain name */
 223 #define RES_STAYOPEN    0x00000100      /* Keep TCP socket open */
 224 #define RES_DNSRCH      0x00000200      /* search up local domain tree */
 225 #define RES_INSECURE1   0x00000400      /* type 1 security disabled */
 226 #define RES_INSECURE2   0x00000800      /* type 2 security disabled */
 227 #define RES_NOALIASES   0x00001000      /* shuts off HOSTALIASES feature */
 228 #define RES_USE_INET6   0x00002000      /* use/map IPv6 in gethostbyname() */
 229 #define RES_ROTATE      0x00004000      /* rotate ns list after each query */
 230 #define RES_NOCHECKNAME 0x00008000      /* do not check names for sanity. */
 231 #define RES_KEEPTSIG    0x00010000      /* do not strip TSIG records */
 232
 233 #define RES_DEFAULT     (RES_RECURSE | RES_DEFNAMES | RES_DNSRCH)
 234
 235 /*
 236  * Resolver "pfcode" values.  Used by dig.
 237  */
 238 #define RES_PRF_STATS   0x00000001
 239 #define RES_PRF_UPDATE  0x00000002
 240 #define RES_PRF_CLASS   0x00000004
 241 #define RES_PRF_CMD     0x00000008
 242 #define RES_PRF_QUES    0x00000010
 243 #define RES_PRF_ANS     0x00000020
 244 #define RES_PRF_AUTH    0x00000040
 245 #define RES_PRF_ADD     0x00000080
 246 #define RES_PRF_HEAD1   0x00000100
 247 #define RES_PRF_HEAD2   0x00000200
 248 #define RES_PRF_TTLID   0x00000400
 249 #define RES_PRF_HEADX   0x00000800
 250 #define RES_PRF_QUERY   0x00001000
 251 #define RES_PRF_REPLY   0x00002000
 252 #define RES_PRF_INIT    0x00004000
 253 /*                      0x00008000      */
 254
 255 /* Things involving an internal (static) resolver context. */
 256 #if defined _REENTRANT || defined _LIBC_REENTRANT
 257 extern struct __res_state *__res_state(void) __attribute__ ((__const__));
 258 # if defined __RES_PTHREAD_INTERNAL
 259 extern struct __res_state _res;
 260 # else
 261 #  define _res (*__res_state())
 262 # endif
 263 #else
 264 extern struct __res_state _res;
 265 #endif
 266
 267 #define fp_nquery               __fp_nquery
 268 #define fp_query                __fp_query
 269 #define hostalias               __hostalias
 270 #define p_query                 __p_query
 271 #define res_close               __res_close
 272 #define res_isourserver         __res_isourserver
 273 #define res_send                __res_send
 274
 275 __BEGIN_DECLS
 276 void            fp_nquery (const u_char *, int, FILE *) __THROW;
 277 void            fp_query (const u_char *, FILE *) __THROW;
 278 const char *    hostalias (const char *) __THROW;
 279 void            p_query (const u_char *) __THROW;
 280 void            res_close (void) __THROW;
 281 int             res_init (void) __THROW;
 282 int             res_isourserver (const struct sockaddr_in *) __THROW;
 283 int             res_mkquery (int, const char *, int, int, const u_char *,
 284                              int, const u_char *, u_char *, int) __THROW;
 285 int             res_query (const char *, int, int, u_char *, int) __THROW;
 286 int             res_querydomain (const char *, const char *, int, int,
 287                                  u_char *, int) __THROW;
 288 int             res_search (const char *, int, int, u_char *, int) __THROW;
 289 int             res_send (const u_char *, int, u_char *, int) __THROW;
 290 __END_DECLS
 291
 292 #if !defined(SHARED_LIBBIND) || defined(_LIBC)
 293 /*
 294  * If libbind is a shared object (well, DLL anyway)
 295  * these externs break the linker when resolv.h is
 296  * included by a lib client (like named)
 297  * Make them go away if a client is including this
 298  *
 299  */
 300 extern const struct res_sym __p_key_syms[];
 301 extern const struct res_sym __p_cert_syms[];
 302 extern const struct res_sym __p_class_syms[];
 303 extern const struct res_sym __p_type_syms[];
 304 extern const struct res_sym __p_rcode_syms[];
 305 #endif /* SHARED_LIBBIND */
 306
 307 #define b64_ntop                __b64_ntop
 308 #define b64_pton                __b64_pton
 309 #define dn_comp                 __dn_comp
 310 #define dn_count_labels         __dn_count_labels
 311 #define dn_skipname             __dn_skipname
 312 #define fp_resstat              __fp_resstat
 313 #define loc_aton                __loc_aton
 314 #define loc_ntoa                __loc_ntoa
 315 #define p_cdname                __p_cdname
 316 #define p_cdnname               __p_cdnname
 317 #define p_class                 __p_class
 318 #define p_fqname                __p_fqname
 319 #define p_fqnname               __p_fqnname
 320 #define p_option                __p_option
 321 #define p_secstodate            __p_secstodate
 322 #define p_section               __p_section
 323 #define p_time                  __p_time
 324 #define p_type                  __p_type
 325 #define p_rcode                 __p_rcode
 326 #define putlong                 __putlong
 327 #define putshort                __putshort
 328 #define res_dnok                __res_dnok
 329 #define res_findzonecut         __res_findzonecut
 330 #define res_hnok                __res_hnok
 331 #define res_hostalias           __res_hostalias
 332 #define res_mailok              __res_mailok
 333 #define res_nameinquery         __res_nameinquery
 334 #define res_nclose              __res_nclose
 335 #define res_ninit               __res_ninit
 336 #define res_nmkquery            __res_nmkquery
 337 #define res_npquery             __res_npquery
 338 #define res_nquery              __res_nquery
 339 #define res_nquerydomain        __res_nquerydomain
 340 #define res_nsearch             __res_nsearch
 341 #define res_nsend               __res_nsend
 342 #define res_nisourserver        __res_nisourserver
 343 #define res_ownok               __res_ownok
 344 #define res_queriesmatch        __res_queriesmatch
 345 #define res_randomid            __res_randomid
 346 #define sym_ntop                __sym_ntop
 347 #define sym_ntos                __sym_ntos
 348 #define sym_ston                __sym_ston
 349 __BEGIN_DECLS
 350 int             res_hnok (const char *) __THROW;
 351 int             res_ownok (const char *) __THROW;
 352 int             res_mailok (const char *) __THROW;
 353 int             res_dnok (const char *) __THROW;
 354 int             sym_ston (const struct res_sym *, const char *, int *) __THROW;
 355 const char *    sym_ntos (const struct res_sym *, int, int *) __THROW;
 356 const char *    sym_ntop (const struct res_sym *, int, int *) __THROW;
 357 int             b64_ntop (u_char const *, size_t, char *, size_t) __THROW;
 358 int             b64_pton (char const *, u_char *, size_t) __THROW;
 359 int             loc_aton (const char *__ascii, u_char *__binary) __THROW;
 360 const char *    loc_ntoa (const u_char *__binary, char *__ascii) __THROW;
 361 int             dn_skipname (const u_char *, const u_char *) __THROW;
 362 void            putlong (u_int32_t, u_char *) __THROW;
 363 void            putshort (u_int16_t, u_char *) __THROW;
 364 const char *    p_class (int) __THROW;
 365 const char *    p_time (u_int32_t) __THROW;
 366 const char *    p_type (int) __THROW;
 367 const char *    p_rcode (int) __THROW;
 368 const u_char *  p_cdnname (const u_char *, const u_char *, int, FILE *)
 369      __THROW;
 370 const u_char *  p_cdname (const u_char *, const u_char *, FILE *) __THROW;
 371 const u_char *  p_fqnname (const u_char *cp, const u_char *msg,
 372                            int, char *, int) __THROW;
 373 const u_char *  p_fqname (const u_char *, const u_char *, FILE *) __THROW;
 374 const char *    p_option (u_long option) __THROW;
 375 char *          p_secstodate (u_long) __THROW;
 376 int             dn_count_labels (const char *) __THROW;
 377 int             dn_comp (const char *, u_char *, int,
 378                              u_char **, u_char **) __THROW;
 379 int             dn_expand (const u_char *, const u_char *, const u_char *,
 380                            char *, int) __THROW;
 381 u_int           res_randomid (void) __THROW;
 382 int             res_nameinquery (const char *, int, int,
 383                                  const u_char *, const u_char *) __THROW;
 384 int             res_queriesmatch (const u_char *, const u_char *,
 385                                   const u_char *, const u_char *) __THROW;
 386 const char *    p_section (int section, int opcode) __THROW;
 387 /* Things involving a resolver context. */
 388 int             res_ninit (res_state) __THROW;
 389 int             res_nisourserver (const res_state,
 390                                   const struct sockaddr_in *) __THROW;
 391 void            fp_resstat (const res_state, FILE *) __THROW;
 392 void            res_npquery (const res_state, const u_char *, int, FILE *) __THROW;
 393 const char *    res_hostalias (const res_state, const char *,
 394                                char *, size_t) __THROW;
 395 int             res_nquery (res_state,
 396                             const char *, int, int, u_char *, int) __THROW;
 397 int             res_nsearch (res_state, const char *, int,
 398                              int, u_char *, int) __THROW;
 399 int             res_nquerydomain (res_state,
 400                                   const char *, const char *, int, int,
 401                                   u_char *, int) __THROW;
 402 int             res_nmkquery (res_state,
 403                               int, const char *, int, int, const u_char *,
 404                               int, const u_char *, u_char *, int) __THROW;
 405 int             res_nsend (res_state, const u_char *, int, u_char *, int) __THROW;
 406 void            res_nclose (res_state) __THROW;
 407 __END_DECLS
 408
 409 #endif /* !_RESOLV_H_ */