include/resolv.h

   1 /*
   2  * Copyright (c) 1983, 1987, 1989
   3  *    The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
  36  *
  37  * Permission to use, copy, modify, and distribute this software for any
  38  * purpose with or without fee is hereby granted, provided that the above
  39  * copyright notice and this permission notice appear in all copies.
  40  *
  41  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
  42  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
  43  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
  44  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
  45  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  46  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
  47  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
  48  * SOFTWARE.
  49  */
  50
  51 /*
  52  *      @(#)resolv.h    8.1 (Berkeley) 6/2/93
  53  *      $Id: resolv.h,v 1.7.2.2 2001/11/03 00:21:34 gson Exp $
  54  */
  55
  56 #ifndef _RESOLV_H_
  57 #define _RESOLV_H_
  58
  59 #include <sys/param.h>
  60 #if !defined(__CYGWIN__) && ((!defined(BSD)) || (BSD < 199306))
  61 # include <sys/bitypes.h>
  62 #else
  63 # include <sys/types.h>
  64 #endif
  65 #include <sys/cdefs.h>
  66 #include <sys/socket.h>
  67 #include <stdio.h>
  68 #include <arpa/nameser.h>
  69
  70 /*
  71  * Revision information.  This is the release date in YYYYMMDD format.
  72  * It can change every day so the right thing to do with it is use it
  73  * in preprocessor commands such as "#if (__RES > 19931104)".  Do not
  74  * compare for equality; rather, use it to determine whether your resolver
  75  * is new enough to contain a certain feature.
  76  */
  77
  78 #define __RES   19991006
  79
  80 /*
  81  * This used to be defined in res_query.c, now it's in herror.c.
  82  * [XXX no it's not.  It's in irs/irs_data.c]
  83  * It was
  84  * never extern'd by any *.h file before it was placed here.  For thread
  85  * aware programs, the last h_errno value set is stored in res->h_errno.
  86  *
  87  * XXX: There doesn't seem to be a good reason for exposing RES_SET_H_ERRNO
  88  *      (and __h_errno_set) to the public via <resolv.h>.
  89  * XXX: __h_errno_set is really part of IRS, not part of the resolver.
  90  *      If somebody wants to build and use a resolver that doesn't use IRS,
  91  *      what do they do?  Perhaps something like
  92  *              #ifdef WANT_IRS
  93  *              # define RES_SET_H_ERRNO(r,x) __h_errno_set(r,x)
  94  *              #else
  95  *              # define RES_SET_H_ERRNO(r,x) (h_errno = (r)->res_h_errno = (x))
  96  *              #endif
  97  */
  98
  99 #define RES_SET_H_ERRNO(r,x) __h_errno_set(r,x)
 100 struct __res_state; /* forward */
 101 __BEGIN_DECLS
 102 void __h_errno_set(struct __res_state *res, int err);
 103 __END_DECLS
 104
 105 /*
 106  * Resolver configuration file.
 107  * Normally not present, but may contain the address of the
 108  * inital name server(s) to query and the domain search list.
 109  */
 110
 111 #ifndef _PATH_RESCONF
 112 #define _PATH_RESCONF        "/etc/resolv.conf"
 113 #endif
 114
 115 typedef enum { res_goahead, res_nextns, res_modified, res_done, res_error }
 116         res_sendhookact;
 117
 118 typedef res_sendhookact (*res_send_qhook)__P((struct sockaddr * const *ns,
 119                                               const u_char **query,
 120                                               int *querylen,
 121                                               u_char *ans,
 122                                               int anssiz,
 123                                               int *resplen));
 124
 125 typedef res_sendhookact (*res_send_rhook)__P((const struct sockaddr *ns,
 126                                               const u_char *query,
 127                                               int querylen,
 128                                               u_char *ans,
 129                                               int anssiz,
 130                                               int *resplen));
 131
 132 struct res_sym {
 133         int             number;    /* Identifying number, like T_MX */
 134         const char *    name;      /* Its symbolic name, like "MX" */
 135         const char *    humanname; /* Its fun name, like "mail exchanger" */
 136 };
 137
 138 /*
 139  * Global defines and variables for resolver stub.
 140  */
 141 #define MAXNS                   3       /* max # name servers we'll track */
 142 #define MAXDFLSRCH              3       /* # default domain levels to try */
 143 #define MAXDNSRCH               6       /* max # domains in search path */
 144 #define LOCALDOMAINPARTS        2       /* min levels in name that is "local" */
 145
 146 #define RES_TIMEOUT             5       /* min. seconds between retries */
 147 #define MAXRESOLVSORT           10      /* number of net to sort on */
 148 #define RES_MAXNDOTS            15      /* should reflect bit field size */
 149 #define RES_MAXRETRANS          30      /* only for resolv.conf/RES_OPTIONS */
 150 #define RES_MAXRETRY            5       /* only for resolv.conf/RES_OPTIONS */
 151 #define RES_DFLRETRY            2       /* Default #/tries. */
 152 #define RES_MAXTIME             65535   /* Infinity, in milliseconds. */
 153
 154 struct __res_state_ext;
 155
 156 struct __res_state {
 157         int     retrans;                /* retransmition time interval */
 158         int     retry;                  /* number of times to retransmit */
 159         u_long  options;                /* option flags - see below. */
 160         int     nscount;                /* number of name servers */
 161         struct sockaddr_in
 162                 nsaddr_list[MAXNS];     /* address of name server */
 163 #define nsaddr  nsaddr_list[0]          /* for backward compatibility */
 164         u_short id;                     /* current message id */
 165         char    *dnsrch[MAXDNSRCH+1];   /* components of domain to search */
 166         char    defdname[256];          /* default domain (deprecated) */
 167         u_long  pfcode;                 /* RES_PRF_ flags - see below. */
 168         unsigned ndots:4;               /* threshold for initial abs. query */
 169         unsigned nsort:4;               /* number of elements in sort_list[] */
 170         char    unused[3];
 171         struct {
 172                 struct in_addr  addr;
 173                 u_int32_t       mask;
 174         } sort_list[MAXRESOLVSORT];
 175         res_send_qhook qhook;           /* query hook */
 176         res_send_rhook rhook;           /* response hook */
 177         int     res_h_errno;            /* last one set for this context */
 178         int     _vcsock;                /* PRIVATE: for res_send VC i/o */
 179         u_int   _flags;                 /* PRIVATE: see below */
 180         union {
 181                 /* On an 32-bit arch this means 512b total. */
 182                 char    pad[72 - 3*sizeof (int) - 2*sizeof (void *)];
 183                 struct {
 184                         u_int16_t               nscount;
 185                         u_int16_t               nstimes[MAXNS]; /* ms. */
 186                         int                     nssocks[MAXNS];
 187                         struct __res_state_ext *ext;    /* extention for IPv6 */
 188                 } _ext;
 189         } _u;
 190 };
 191
 192 typedef struct __res_state *res_state;
 193
 194 union res_sockaddr_union {
 195         struct sockaddr_in      sin;
 196 #ifdef IN6ADDR_ANY_INIT
 197         struct sockaddr_in6     sin6;
 198 #endif
 199 #ifdef ISC_ALIGN64
 200         int64_t                 __align;        /* 64bit alignment */
 201 #else
 202         int32_t                 __align;        /* 32bit alignment */
 203 #endif
 204         char                    __space[128];   /* max size */
 205 };
 206
 207 /*
 208  * Resolver flags (used to be discrete per-module statics ints).
 209  */
 210 #define RES_F_VC        0x00000001      /* socket is TCP */
 211 #define RES_F_CONN      0x00000002      /* socket is connected */
 212 #define RES_F_EDNS0ERR  0x00000004      /* EDNS0 caused errors */
 213
 214 /* res_findzonecut() options */
 215 #define RES_EXHAUSTIVE  0x00000001      /* always do all queries */
 216
 217 /*
 218  * Resolver options (keep these in synch with res_debug.c, please)
 219  */
 220 #define RES_INIT        0x00000001      /* address initialized */
 221 #define RES_DEBUG       0x00000002      /* print debug messages */
 222 #define RES_AAONLY      0x00000004      /* authoritative answers only (!IMPL)*/
 223 #define RES_USEVC       0x00000008      /* use virtual circuit */
 224 #define RES_PRIMARY     0x00000010      /* query primary server only (!IMPL) */
 225 #define RES_IGNTC       0x00000020      /* ignore trucation errors */
 226 #define RES_RECURSE     0x00000040      /* recursion desired */
 227 #define RES_DEFNAMES    0x00000080      /* use default domain name */
 228 #define RES_STAYOPEN    0x00000100      /* Keep TCP socket open */
 229 #define RES_DNSRCH      0x00000200      /* search up local domain tree */
 230 #define RES_INSECURE1   0x00000400      /* type 1 security disabled */
 231 #define RES_INSECURE2   0x00000800      /* type 2 security disabled */
 232 #define RES_NOALIASES   0x00001000      /* shuts off HOSTALIASES feature */
 233 #define RES_USE_INET6   0x00002000      /* use/map IPv6 in gethostbyname() */
 234 #define RES_ROTATE      0x00004000      /* rotate ns list after each query */
 235 #define RES_NOCHECKNAME 0x00008000      /* do not check names for sanity. */
 236 #define RES_KEEPTSIG    0x00010000      /* do not strip TSIG records */
 237 #define RES_BLAST       0x00020000      /* blast all recursive servers */
 238 #define RES_NO_NIBBLE   0x00040000      /* disable IPv6 nibble mode reverse */
 239 #define RES_NO_BITSTRING 0x00080000     /* disable IPv6 bit string mode reverse */
 240 /* KAME extensions: use higher bit to avoid conflict with ISC use */
 241 #define RES_USE_DNAME   0x10000000      /* use DNAME */
 242 #define RES_USE_A6      0x20000000      /* use A6 */
 243 #define RES_USE_EDNS0   0x40000000      /* use EDNS0 if configured */
 244
 245 #define RES_DEFAULT     (RES_RECURSE | RES_DEFNAMES | RES_DNSRCH)
 246
 247 /*
 248  * Resolver "pfcode" values.  Used by dig.
 249  */
 250 #define RES_PRF_STATS   0x00000001
 251 #define RES_PRF_UPDATE  0x00000002
 252 #define RES_PRF_CLASS   0x00000004
 253 #define RES_PRF_CMD     0x00000008
 254 #define RES_PRF_QUES    0x00000010
 255 #define RES_PRF_ANS     0x00000020
 256 #define RES_PRF_AUTH    0x00000040
 257 #define RES_PRF_ADD     0x00000080
 258 #define RES_PRF_HEAD1   0x00000100
 259 #define RES_PRF_HEAD2   0x00000200
 260 #define RES_PRF_TTLID   0x00000400
 261 #define RES_PRF_HEADX   0x00000800
 262 #define RES_PRF_QUERY   0x00001000
 263 #define RES_PRF_REPLY   0x00002000
 264 #define RES_PRF_INIT    0x00004000
 265 /*                      0x00008000      */
 266
 267 /* Things involving an internal (static) resolver context. */
 268 #if defined(_REENTRANT) || defined(__CYGWIN__)
 269 __BEGIN_DECLS
 270 extern struct __res_state *__res_state(void);
 271 __END_DECLS
 272 #define _res (*__res_state())
 273 #else
 274 #ifndef __BIND_NOSTATIC
 275 extern struct __res_state _res;
 276 #endif
 277 #endif
 278
 279 #ifndef __BIND_NOSTATIC
 280 #define fp_nquery               __fp_nquery
 281 #define fp_query                __fp_query
 282 #define hostalias               __hostalias
 283 #define p_query                 __p_query
 284 #define res_close               __res_close
 285 #define res_init                __res_init
 286 #define res_isourserver         __res_isourserver
 287 #define res_mkquery             __res_mkquery
 288 #define res_query               __res_query
 289 #define res_querydomain         __res_querydomain
 290 #define res_search              __res_search
 291 #define res_send                __res_send
 292 #define res_sendsigned          __res_sendsigned
 293
 294 __BEGIN_DECLS
 295 void            fp_nquery __P((const u_char *, int, FILE *));
 296 void            fp_query __P((const u_char *, FILE *));
 297 const char *    hostalias __P((const char *));
 298 void            p_query __P((const u_char *));
 299 void            res_close __P((void));
 300 int             res_init __P((void));
 301 int             res_isourserver __P((const struct sockaddr_in *));
 302 int             res_mkquery __P((int, const char *, int, int, const u_char *,
 303                                  int, const u_char *, u_char *, int));
 304 int             res_query __P((const char *, int, int, u_char *, int));
 305 int             res_querydomain __P((const char *, const char *, int, int,
 306                                      u_char *, int));
 307 int             res_search __P((const char *, int, int, u_char *, int));
 308 int             res_send __P((const u_char *, int, u_char *, int));
 309 int             res_sendsigned __P((const u_char *, int, ns_tsig_key *,
 310                                     u_char *, int));
 311 __END_DECLS
 312 #endif
 313
 314 #if !defined(SHARED_LIBBIND) || defined(LIB)
 315 /*
 316  * If libbind is a shared object (well, DLL anyway)
 317  * these externs break the linker when resolv.h is
 318  * included by a lib client (like named)
 319  * Make them go away if a client is including this
 320  *
 321  */
 322 extern const struct res_sym __p_key_syms[];
 323 extern const struct res_sym __p_cert_syms[];
 324 extern const struct res_sym __p_class_syms[];
 325 extern const struct res_sym __p_type_syms[];
 326 extern const struct res_sym __p_rcode_syms[];
 327 #endif /* SHARED_LIBBIND */
 328
 329 #define b64_ntop                __b64_ntop
 330 #define b64_pton                __b64_pton
 331 #define dn_comp                 __dn_comp
 332 #define dn_count_labels         __dn_count_labels
 333 #define dn_expand               __dn_expand
 334 #define dn_skipname             __dn_skipname
 335 #define fp_resstat              __fp_resstat
 336 #define loc_aton                __loc_aton
 337 #define loc_ntoa                __loc_ntoa
 338 #define p_cdname                __p_cdname
 339 #define p_cdnname               __p_cdnname
 340 #define p_class                 __p_class
 341 #define p_fqname                __p_fqname
 342 #define p_fqnname               __p_fqnname
 343 #define p_option                __p_option
 344 #define p_secstodate            __p_secstodate
 345 #define p_section               __p_section
 346 #define p_time                  __p_time
 347 #define p_type                  __p_type
 348 #define p_rcode                 __p_rcode
 349 #define putlong                 __putlong
 350 #define putshort                __putshort
 351 #define res_dnok                __res_dnok
 352 #define res_findzonecut         __res_findzonecut
 353 #define res_hnok                __res_hnok
 354 #define res_hostalias           __res_hostalias
 355 #define res_mailok              __res_mailok
 356 #define res_nameinquery         __res_nameinquery
 357 #define res_nclose              __res_nclose
 358 #define res_ninit               __res_ninit
 359 #define res_nmkquery            __res_nmkquery
 360 #define res_pquery              __res_pquery
 361 #define res_nquery              __res_nquery
 362 #define res_nquerydomain        __res_nquerydomain
 363 #define res_nsearch             __res_nsearch
 364 #define res_nsend               __res_nsend
 365 #define res_nsendsigned         __res_nsendsigned
 366 #define res_nisourserver        __res_nisourserver
 367 #define res_ownok               __res_ownok
 368 #define res_queriesmatch        __res_queriesmatch
 369 #define res_randomid            __res_randomid
 370 #define sym_ntop                __sym_ntop
 371 #define sym_ntos                __sym_ntos
 372 #define sym_ston                __sym_ston
 373 #define res_nopt                __res_nopt
 374 #define res_ndestroy            __res_ndestroy
 375 #define res_nametoclass         __res_nametoclass
 376 #define res_nametotype          __res_nametotype
 377 #define res_setservers          __res_setservers
 378 #define res_getservers          __res_getservers
 379 __BEGIN_DECLS
 380 int             res_hnok __P((const char *));
 381 int             res_ownok __P((const char *));
 382 int             res_mailok __P((const char *));
 383 int             res_dnok __P((const char *));
 384 int             sym_ston __P((const struct res_sym *, const char *, int *));
 385 const char *    sym_ntos __P((const struct res_sym *, int, int *));
 386 const char *    sym_ntop __P((const struct res_sym *, int, int *));
 387 int             b64_ntop __P((u_char const *, size_t, char *, size_t));
 388 int             b64_pton __P((char const *, u_char *, size_t));
 389 int             loc_aton __P((const char *ascii, u_char *binary));
 390 const char *    loc_ntoa __P((const u_char *binary, char *ascii));
 391 int             dn_skipname __P((const u_char *, const u_char *));
 392 void            putlong __P((u_int32_t, u_char *));
 393 void            putshort __P((u_int16_t, u_char *));
 394 #ifndef __ultrix__
 395 u_int16_t       _getshort __P((const u_char *src));
 396 u_int32_t       _getlong __P((const u_char *src));
 397 #endif
 398 const char *    p_class __P((int));
 399 const char *    p_time __P((u_int32_t));
 400 const char *    p_type __P((int));
 401 const char *    p_rcode __P((int));
 402 const u_char *  p_cdnname __P((const u_char *, const u_char *, int, FILE *));
 403 const u_char *  p_cdname __P((const u_char *, const u_char *, FILE *));
 404 const u_char *  p_fqnname __P((const u_char *cp, const u_char *msg,
 405                                int, char *, int));
 406 const u_char *  p_fqname __P((const u_char *, const u_char *, FILE *));
 407 const char *    p_option __P((u_long option));
 408 char *          p_secstodate __P((u_long));
 409 int             dn_count_labels __P((const char *));
 410 int             dn_comp __P((const char *, u_char *, int,
 411                              u_char **, u_char **));
 412 int             dn_expand __P((const u_char *, const u_char *, const u_char *,
 413                                char *, int));
 414 u_int           res_randomid __P((void));
 415 int             res_nameinquery __P((const char *, int, int,
 416                                      const u_char *, const u_char *));
 417 int             res_queriesmatch __P((const u_char *, const u_char *,
 418                                       const u_char *, const u_char *));
 419 const char *    p_section __P((int section, int opcode));
 420 /* Things involving a resolver context. */
 421 int             res_ninit __P((res_state));
 422 int             res_nisourserver __P((const res_state,
 423                                       const struct sockaddr_in *));
 424 void            fp_resstat __P((const res_state, FILE *));
 425 void            res_pquery __P((const res_state, const u_char *, int, FILE *));
 426 const char *    res_hostalias __P((const res_state, const char *,
 427                                    char *, size_t));
 428 int             res_nquery __P((res_state,
 429                                 const char *, int, int, u_char *, int));
 430 int             res_nsearch __P((res_state, const char *, int,
 431                                  int, u_char *, int));
 432 int             res_nquerydomain __P((res_state,
 433                                       const char *, const char *, int, int,
 434                                       u_char *, int));
 435 int             res_nmkquery __P((res_state,
 436                                   int, const char *, int, int, const u_char *,
 437                                   int, const u_char *, u_char *, int));
 438 int             res_nsend __P((res_state, const u_char *, int, u_char *, int));
 439 int             res_nsendsigned __P((res_state, const u_char *, int,
 440                                      ns_tsig_key *, u_char *, int));
 441 int             res_findzonecut __P((res_state, const char *, ns_class, int,
 442                                      char *, size_t, struct in_addr *, int));
 443 void            res_nclose __P((res_state));
 444 int             res_nopt __P((res_state, int, u_char *, int, int));
 445 void            res_send_setqhook __P((res_send_qhook hook));
 446 void            res_send_setrhook __P((res_send_rhook hook));
 447 int             __res_vinit __P((res_state, int));
 448 void            res_destroyservicelist __P((void));
 449 const char *    res_servicename __P((u_int16_t port, const char *proto));
 450 const char *    res_protocolname __P((int num));
 451 void            res_destroyprotolist __P((void));
 452 void            res_buildprotolist __P((void));
 453 const char *    res_get_nibblesuffix __P((res_state));
 454 const char *    res_get_bitstringsuffix __P((res_state));
 455 void            res_ndestroy __P((res_state));
 456 u_int16_t       res_nametoclass __P((const char *buf, int *success));
 457 u_int16_t       res_nametotype __P((const char *buf, int *success));
 458 void            res_setservers __P((res_state,
 459                                     const union res_sockaddr_union *, int));
 460 int             res_getservers __P((res_state,
 461                                     union res_sockaddr_union *, int));
 462 __END_DECLS
 463
 464 #endif /* !_RESOLV_H_ */