/*      $NetBSD: res_data.c,v 1.14 2009/10/24 05:35:37 christos Exp $   */

/*
 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
 * Copyright (c) 1995-1999 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.
 */

#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
#ifdef notdef
static const char rcsid[] = "Id: res_data.c,v 1.7 2008/12/11 09:59:00 marka Exp";
#else
__RCSID("$NetBSD: res_data.c,v 1.14 2009/10/24 05:35:37 christos Exp $");
#endif
#endif /* LIBC_SCCS and not lint */

#include "port_before.h"

#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/time.h>

#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>

#include <ctype.h>
#include <netdb.h>
#include <resolv.h>
#include <res_update.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "port_after.h"

#include "res_private.h"

#ifdef __weak_alias
__weak_alias(res_init,_res_init)
__weak_alias(res_mkquery,_res_mkquery)
__weak_alias(res_query,_res_query)
__weak_alias(res_search,_res_search)
__weak_alias(res_send,__res_send)
__weak_alias(res_close,__res_close)
/* XXX: these leaked in the old bind8 libc */
__weak_alias(res_querydomain,__res_querydomain)
__weak_alias(res_send_setqhook,__res_send_setqhook)
__weak_alias(res_send_setrhook,__res_send_setrhook)
#if 0
__weak_alias(p_query,__p_query)
__weak_alias(fp_query,__fp_query)
__weak_alias(fp_nquery,__fp_nquery)
__weak_alias(res_isourserver,__res_isourserver)
__weak_alias(res_opt,_res_opt)
__weak_alias(hostalias,__hostalias)
#endif
#endif

const char *_res_opcodes[] = {
        "QUERY",
        "IQUERY",
        "CQUERYM",
        "CQUERYU",      /*%< experimental */
        "NOTIFY",       /*%< experimental */
        "UPDATE",
        "6",
        "7",
        "8",
        "9",
        "10",
        "11",
        "12",
        "13",
        "ZONEINIT",
        "ZONEREF",
};

#ifdef BIND_UPDATE
const char *_res_sectioncodes[] = {
        "ZONE",
        "PREREQUISITES",
        "UPDATE",
        "ADDITIONAL",
};
#endif

#ifndef __BIND_NOSTATIC 
extern struct __res_state _nres;

/* Proto. */

int  res_ourserver_p(const res_state, const struct sockaddr *);

int
res_init(void) {
        int rv;
#ifdef COMPAT__RES
        /*
         * Compatibility with program that were accessing _res directly
         * to set options. We keep another struct res that is the same
         * size as the original res structure, and then copy fields to
         * it so that we achieve the same initialization
         */
        extern void *__res_get_old_state(void);
        extern void __res_put_old_state(void *);
        res_state ores = __res_get_old_state();

        if (ores->options != 0)
                _nres.options = ores->options;
        if (ores->retrans != 0)
                _nres.retrans = ores->retrans;
        if (ores->retry != 0)
                _nres.retry = ores->retry;
#endif

        /*
         * These three fields used to be statically initialized.  This made
         * it hard to use this code in a shared library.  It is necessary,
         * now that we're doing dynamic initialization here, that we preserve
         * the old semantics: if an application modifies one of these three
         * fields of _res before res_init() is called, res_init() will not
         * alter them.  Of course, if an application is setting them to
         * _zero_ before calling res_init(), hoping to override what used
         * to be the static default, we can't detect it and unexpected results
         * will follow.  Zero for any of these fields would make no sense,
         * so one can safely assume that the applications were already getting
         * unexpected results.
         *
         * _nres.options is tricky since some apps were known to diddle the bits
         * before res_init() was first called. We can't replicate that semantic
         * with dynamic initialization (they may have turned bits off that are
         * set in RES_DEFAULT).  Our solution is to declare such applications
         * "broken".  They could fool us by setting RES_INIT but none do (yet).
         */
        if (!_nres.retrans)
                _nres.retrans = RES_TIMEOUT;
        if (!_nres.retry)
                _nres.retry = 4;
        if (!(_nres.options & RES_INIT))
                _nres.options = RES_DEFAULT;

        /*
         * This one used to initialize implicitly to zero, so unless the app
         * has set it to something in particular, we can randomize it now.
         */
        if (!_nres.id)
                _nres.id = res_nrandomid(&_nres);

        rv = __res_vinit(&_nres, 1);
#ifdef COMPAT__RES
        __res_put_old_state(&_nres);
#endif
        return rv;
}

void
p_query(const u_char *msg) {
        fp_query(msg, stdout);
}

void
fp_query(const u_char *msg, FILE *file) {
        fp_nquery(msg, PACKETSZ, file);
}

void
fp_nquery(const u_char *msg, int len, FILE *file) {
        if ((_nres.options & RES_INIT) == 0U && res_init() == -1)
                return;

        res_pquery(&_nres, msg, len, file);
}

int
res_mkquery(int op,                     /*!< opcode of query  */
            const char *dname,          /*!< domain name  */
            int class, int type,        /*!< class and type of query  */
            const u_char *data,         /*!< resource record data  */
            int datalen,                /*!< length of data  */
            const u_char *newrr_in,     /*!< new rr for modify or append  */
            u_char *buf,                /*!< buffer to put query  */
            int buflen)                 /*!< size of buffer  */
{
        if ((_nres.options & RES_INIT) == 0U && res_init() == -1) {
                RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
                return (-1);
        }
        return (res_nmkquery(&_nres, op, dname, class, type,
                             data, datalen,
                             newrr_in, buf, buflen));
}

#ifdef _LIBRESOLV
int
res_mkupdate(ns_updrec *rrecp_in, u_char *buf, int buflen) {
        if ((_nres.options & RES_INIT) == 0U && res_init() == -1) {
                RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
                return (-1);
        }

        return (res_nmkupdate(&_nres, rrecp_in, buf, buflen));
}
#endif

int
res_query(const char *name,     /*!< domain name  */
          int class, int type,  /*!< class and type of query  */
          u_char *answer,       /*!< buffer to put answer  */
          int anslen)           /*!< size of answer buffer  */
{
        if ((_nres.options & RES_INIT) == 0U && res_init() == -1) {
                RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
                return (-1);
        }
        return (res_nquery(&_nres, name, class, type, answer, anslen));
}

void
res_send_setqhook(res_send_qhook hook) {
        _nres.qhook = hook;
}

void
res_send_setrhook(res_send_rhook hook) {
        _nres.rhook = hook;
}

int
res_isourserver(const struct sockaddr_in *inp) {
        return (res_ourserver_p(&_nres, (const struct sockaddr *)(const void *)inp));
}

int
res_send(const u_char *buf, int buflen, u_char *ans, int anssiz) {
        if ((_nres.options & RES_INIT) == 0U && res_init() == -1) {
                /* errno should have been set by res_init() in this case. */
                return (-1);
        }

        return (res_nsend(&_nres, buf, buflen, ans, anssiz));
}

#ifdef _LIBRESOLV
int
res_sendsigned(const u_char *buf, int buflen, ns_tsig_key *key,
               u_char *ans, int anssiz)
{
        if ((_nres.options & RES_INIT) == 0U && res_init() == -1) {
                /* errno should have been set by res_init() in this case. */
                return (-1);
        }

        return (res_nsendsigned(&_nres, buf, buflen, key, ans, anssiz));
}
#endif

void
res_close(void) {
        res_nclose(&_nres);
}

#ifdef _LIBRESOLV
int
res_update(ns_updrec *rrecp_in) {
        if ((_nres.options & RES_INIT) == 0U && res_init() == -1) {
                RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
                return (-1);
        }

        return (res_nupdate(&_nres, rrecp_in, NULL));
}
#endif

int
res_search(const char *name,    /*!< domain name  */
           int class, int type, /*!< class and type of query  */
           u_char *answer,      /*!< buffer to put answer  */
           int anslen)          /*!< size of answer  */
{
        if ((_nres.options & RES_INIT) == 0U && res_init() == -1) {
                RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
                return (-1);
        }

        return (res_nsearch(&_nres, name, class, type, answer, anslen));
}

int
res_querydomain(const char *name,
                const char *domain,
                int class, int type,    /*!< class and type of query  */
                u_char *answer,         /*!< buffer to put answer  */
                int anslen)             /*!< size of answer  */
{
        if ((_nres.options & RES_INIT) == 0U && res_init() == -1) {
                RES_SET_H_ERRNO(&_nres, NETDB_INTERNAL);
                return (-1);
        }

        return (res_nquerydomain(&_nres, name, domain,
                                 class, type,
                                 answer, anslen));
}

int
res_opt(int a, u_char *b, int c, int d)
{
        return res_nopt(&_nres, a, b, c, d);
}

u_int
res_randomid(void) {
        if ((_nres.options & RES_INIT) == 0U && res_init() == -1) {
                RES_SET_H_ERRNO(&_res, NETDB_INTERNAL);
                return (u_int)-1;
        }

        return (res_nrandomid(&_nres));
}

const char *
hostalias(const char *name) {
        static char abuf[MAXDNAME];

        return (res_hostalias(&_nres, name, abuf, sizeof abuf));
}

#ifdef ultrix
int
local_hostname_length(const char *hostname) {
        int len_host, len_domain;

        if (!*_nres.defdname)
                res_init();
        len_host = strlen(hostname);
        len_domain = strlen(_nres.defdname);
        if (len_host > len_domain &&
            !strcasecmp(hostname + len_host - len_domain, _nres.defdname) &&
            hostname[len_host - len_domain - 1] == '.')
                return (len_host - len_domain - 1);
        return (0);
}
#endif /*ultrix*/

#endif

/*! \file */