resolv.h

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/*
 * Copyright (c) 1983, 1987, 1989
 *    The Regents of the University of California.  All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
 * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*%
 *      @(#)resolv.h    8.1 (Berkeley) 6/2/93
 * $FreeBSD: release/9.0.0/include/resolv.h 203964 2010-02-16 19:39:50Z imp $
 */

#ifndef _RESOLV_H_
#define _RESOLV_H_

#include <sys/param.h>
#include <sys/types.h>
#include <sys/cdefs.h>
#include <stdio.h>
#include <netinet/in.h> /* struct in_addr */

/*%
 * Revision information.  This is the release date in YYYYMMDD format.
 * It can change every day so the right thing to do with it is use it
 * in preprocessor commands such as "#if (__RES > 19931104)".  Do not
 * compare for equality; rather, use it to determine whether your resolver
 * is new enough to contain a certain feature.
 */

#define __RES   19960801

/*%
 * This used to be defined in res_query.c, now it's in herror.c.  It was
 * never extern'd by any *.h file before it was placed here.  herror.c is
 * part of libresolv.a even though it might make more sense in libnetdb.a
 * or even libnet.a.
 */

extern int h_errno;

/*%
 * Resolver configuration file.
 * Normally not present, but may contain the address of the
 * initial name server(s) to query and the domain search list.
 */

#ifndef _PATH_RESCONF
#define _PATH_RESCONF        "/etc/resolv.conf"
#endif

typedef enum { res_goahead, res_nextns, res_modified, res_done, res_error }
        res_sendhookact;

typedef res_sendhookact (*res_send_qhook)(struct sockaddr_in * const *ns,
                                              const u_char **query,
                                              int *querylen,
                                              u_char *ans,
                                              int anssiz,
                                              int *resplen);

typedef res_sendhookact (*res_send_rhook)(const struct sockaddr_in *ns,
                                              const u_char *query,
                                              int querylen,
                                              u_char *ans,
                                              int anssiz,
                                              int *resplen);

struct res_sym {
        int             number;    /*%< Identifying number, like T_MX */
        const char *    name;      /*%< Its symbolic name, like "MX" */
        const char *    humanname; /*%< Its fun name, like "mail exchanger" */
};

/*%
 * Global defines and variables for resolver stub.
 */
#define MAXNS                   3       /*%< max # name servers we'll track */
#define MAXDFLSRCH              3       /*%< # default domain levels to try */
#define MAXDNSRCH               6       /*%< max # domains in search path */
#define LOCALDOMAINPARTS        2       /*%< min levels in name that is "local" */
#define RES_TIMEOUT             5       /*%< min. seconds between retries */
#define MAXRESOLVSORT           10      /*%< number of net to sort on */
#define RES_MAXNDOTS            15      /*%< should reflect bit field size */

struct __res_state {
        int     retrans;                /*%< retransmission time interval */
        int     retry;                  /*%< number of times to retransmit */
        u_long  options;                /*%< option flags - see below. */
        int     nscount;                /*%< number of name servers */
        struct sockaddr_in
                nsaddr_list[MAXNS];     /*%< address of name server */
#define nsaddr  nsaddr_list[0]          /*%< for backward compatibility */
        u_short id;                     /*%< current message id */
        char    *dnsrch[MAXDNSRCH+1];   /*%< components of domain to search */
        char    defdname[256];          /*%< default domain (deprecated) */
        u_long  pfcode;                 /*%< RES_PRF_ flags - see below. */
        unsigned ndots:4;               /*%< threshold for initial abs. query */
        unsigned nsort:4;               /*%< number of elements in sort_list[] */
        char    unused[3];
        struct {
                struct in_addr  addr;
                u_int32_t       mask;
        } sort_list[MAXRESOLVSORT];
        char    pad[72];                /* on an i386 this means 512b total */
};

typedef struct __res_state *res_state;

/*%
 * Resolver options (keep these in synch with res_debug.c, please)
 */
#define RES_INIT        0x00000001      /*%< address initialized */
#define RES_DEBUG       0x00000002      /*%< print debug messages */
#define RES_AAONLY      0x00000004      /*%< authoritative answers only (!IMPL)*/
#define RES_USEVC       0x00000008      /*%< use virtual circuit */
#define RES_PRIMARY     0x00000010      /*%< query primary server only (!IMPL) */
#define RES_IGNTC       0x00000020      /*%< ignore truncation errors */
#define RES_RECURSE     0x00000040      /*%< recursion desired */
#define RES_DEFNAMES    0x00000080      /*%< use default domain name */
#define RES_STAYOPEN    0x00000100      /*%< Keep TCP socket open */
#define RES_DNSRCH      0x00000200      /*%< search up local domain tree */
#define RES_INSECURE1   0x00000400      /*%< type 1 security disabled */
#define RES_INSECURE2   0x00000800      /*%< type 2 security disabled */
#define RES_NOALIASES   0x00001000      /*%< shuts off HOSTALIASES feature */
#define RES_USE_INET6   0x00002000      /*%< use/map IPv6 in gethostbyname() */
#define RES_NOTLDQUERY  0x00004000      /*%< Don't query TLD names */

#define RES_DEFAULT     (RES_RECURSE | RES_DEFNAMES | \
                         RES_DNSRCH)

/*%
 * Resolver "pfcode" values.  Used by dig.
 */
#define RES_PRF_STATS   0x00000001
#define RES_PRF_UPDATE  0x00000002
#define RES_PRF_CLASS   0x00000004
#define RES_PRF_CMD     0x00000008
#define RES_PRF_QUES    0x00000010
#define RES_PRF_ANS     0x00000020
#define RES_PRF_AUTH    0x00000040
#define RES_PRF_ADD     0x00000080
#define RES_PRF_HEAD1   0x00000100
#define RES_PRF_HEAD2   0x00000200
#define RES_PRF_TTLID   0x00000400
#define RES_PRF_HEADX   0x00000800
#define RES_PRF_QUERY   0x00001000
#define RES_PRF_REPLY   0x00002000
#define RES_PRF_INIT    0x00004000
/*                      0x00008000      */

#define fp_nquery               __fp_nquery
#define fp_query                __fp_query
#define hostalias               __hostalias
#define p_query                 __p_query
#define res_close               __res_close
#define res_init                __res_init
#define res_isourserver         __res_isourserver
#define res_mkquery             __res_mkquery
#define res_query               __res_query
#define res_querydomain         __res_querydomain
#define res_search              __res_search
#define res_send                __res_send

__BEGIN_DECLS
void            fp_nquery(const u_char *, int, FILE *);
void            fp_query(const u_char *, FILE *);
const char *    hostalias(const char *);
void            p_query(const u_char *);
void            res_close(void);
int             res_init(void);
int             res_isourserver(const struct sockaddr_in *);
int             res_mkquery(int, const char *, int, int, const u_char *,
                                 int, const u_char *, u_char *, int);
int             res_query(const char *, int, int, u_char *, int);
int             res_querydomain(const char *, const char *, int, int,
                                     u_char *, int);
int             res_search(const char *, int, int, u_char *, int);
int             res_send(const u_char *, int, u_char *, int);
__END_DECLS

extern struct __res_state _res;


extern const struct res_sym __p_class_syms[];
extern const struct res_sym __p_type_syms[];

/* Private routines shared between libc/net, named, nslookup and others. */
#define b64_ntop                __b64_ntop
#define b64_pton                __b64_pton
#define dn_comp                 __dn_comp
#define dn_count_labels         __dn_count_labels
#define dn_expand               __dn_expand
#define dn_skipname             __dn_skipname
#define fp_resstat              __fp_resstat
#define loc_aton                __loc_aton
#define loc_ntoa                __loc_ntoa
#define p_cdname                __p_cdname
#define p_cdnname               __p_cdnname
#define fp_resstat              __fp_resstat
#define p_class                 __p_class
#define p_fqname                __p_fqname
#define p_fqnname               __p_fqnname
#define p_option                __p_option
#define p_secstodate            __p_secstodate
#define p_section               __p_section
#define p_time                  __p_time
#define p_type                  __p_type
#define putlong                 __putlong
#define putshort                __putshort
#define res_dnok                __res_dnok
#define res_hnok                __res_hnok
#define res_mailok              __res_mailok
#define res_nameinquery         __res_nameinquery
#define res_ownok               __res_ownok
#define res_queriesmatch        __res_queriesmatch
#define res_randomid            __res_randomid
#define sym_ntop                __sym_ntop
#define sym_ntos                __sym_ntos
#define sym_ston                __sym_ston
#define res_send_setqhook       __res_send_setqhook
#define res_send_setrhook       __res_send_setrhook
#define res_mkupdate            __res_mkupdate
#define res_mkupdrec            __res_mkupdrec
#define res_freeupdrec          __res_freeupdrec

__BEGIN_DECLS
int             res_hnok(const char *);
int             res_ownok(const char *);
int             res_mailok(const char *);
int             res_dnok(const char *);
int             sym_ston(const struct res_sym *, const char *, int *);
const char *    sym_ntos(const struct res_sym *, int, int *);
const char *    sym_ntop(const struct res_sym *, int, int *);
int             b64_ntop(u_char const *, size_t, char *, size_t);
int             b64_pton(char const *, u_char *, size_t);
int             loc_aton(const char *, u_char *);
const char *    loc_ntoa(const u_char *, char *);
int             dn_skipname(const u_char *, const u_char *);
void            fp_resstat(struct __res_state *, FILE *);
void            putlong(u_int32_t, u_char *);
void            putshort(u_int16_t, u_char *);
const char *    p_class(int);
const char *    p_time(u_int32_t);
const char *    p_type(int);
const u_char *  p_cdnname(const u_char *, const u_char *, int, FILE *);
const u_char *  p_cdname(const u_char *, const u_char *, FILE *);
const u_char *  p_fqnname(const u_char *, const u_char *, int, char *, int);
const u_char *  p_fqname(const u_char *, const u_char *, FILE *);
const char *    p_option(u_long);
char *          p_secstodate(u_long);
int             dn_count_labels(const char *);
int             dn_comp(const char *, u_char *, int, u_char **, u_char **);
int             dn_expand(const u_char *, const u_char *, const u_char *,
                          char *, int);
u_int           res_randomid(void);
int             res_nameinquery(const char *, int, int, const u_char *,
                                const u_char *);
int             res_queriesmatch(const u_char *, const u_char *,
                                 const u_char *, const u_char *);
const char *    p_section(int, int);
void            res_send_setqhook(res_send_qhook);
void            res_send_setrhook(res_send_rhook);

/* XXX The following depend on the ns_updrec typedef in arpa/nameser.h */
#ifdef _ARPA_NAMESER_H_
int             res_update (ns_updrec *);
int             res_mkupdate (ns_updrec *, u_char *, int);
ns_updrec *     res_mkupdrec (int, const char *, u_int, u_int, u_long);
void            res_freeupdrec (ns_updrec *);
#endif
__END_DECLS

#endif /* !_RESOLV_H_ */