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/*
* Copyright (C) Internet Systems Consortium, Inc. ("ISC")
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* See the COPYRIGHT file distributed with this work for additional
* information regarding copyright ownership.
*/
/*
* A simple database driver that enables the server to return the
* current time in a DNS record.
*/
#include <config.h>
#include <string.h>
#include <stdio.h>
#include <time.h>
#include <isc/print.h>
#include <isc/result.h>
#include <isc/util.h>
#include <dns/sdb.h>
#include <named/globals.h>
#include "timedb.h"
static dns_sdbimplementation_t *timedb = NULL;
/*
* This database operates on relative names.
*
* "time" and "@" return the time in a TXT record.
* "clock" is a CNAME to "time"
* "current" is a DNAME to "@" (try time.current.time)
*/
#ifdef DNS_CLIENTINFO_VERSION
static isc_result_t
timedb_lookup(const char *zone, const char *name, void *dbdata,
dns_sdblookup_t *lookup, dns_clientinfomethods_t *methods,
dns_clientinfo_t *clientinfo)
#else
static isc_result_t
timedb_lookup(const char *zone, const char *name, void *dbdata,
dns_sdblookup_t *lookup)
#endif /* DNS_CLIENTINFO_VERSION */
{
isc_result_t result;
UNUSED(zone);
UNUSED(dbdata);
#ifdef DNS_CLIENTINFO_VERSION
UNUSED(methods);
UNUSED(clientinfo);
#endif /* DNS_CLIENTINFO_VERSION */
if (strcmp(name, "@") == 0 || strcmp(name, "time") == 0) {
time_t now = time(NULL);
char buf[100];
int n;
/*
* Call ctime to create the string, put it in quotes, and
* remove the trailing newline.
*/
n = snprintf(buf, sizeof(buf), "\"%s", ctime(&now));
if (n < 0)
return (ISC_R_FAILURE);
buf[n - 1] = '\"';
result = dns_sdb_putrr(lookup, "txt", 1, buf);
if (result != ISC_R_SUCCESS)
return (ISC_R_FAILURE);
} else if (strcmp(name, "clock") == 0) {
result = dns_sdb_putrr(lookup, "cname", 1, "time");
if (result != ISC_R_SUCCESS)
return (ISC_R_FAILURE);
} else if (strcmp(name, "current") == 0) {
result = dns_sdb_putrr(lookup, "dname", 1, "@");
if (result != ISC_R_SUCCESS)
return (ISC_R_FAILURE);
} else
return (ISC_R_NOTFOUND);
return (ISC_R_SUCCESS);
}
/*
* lookup() does not return SOA or NS records, so authority() must be defined.
*/
static isc_result_t
timedb_authority(const char *zone, void *dbdata, dns_sdblookup_t *lookup) {
isc_result_t result;
UNUSED(zone);
UNUSED(dbdata);
result = dns_sdb_putsoa(lookup, "localhost.", "root.localhost.", 0);
if (result != ISC_R_SUCCESS)
return (ISC_R_FAILURE);
result = dns_sdb_putrr(lookup, "ns", 86400, "ns1.localdomain.");
if (result != ISC_R_SUCCESS)
return (ISC_R_FAILURE);
result = dns_sdb_putrr(lookup, "ns", 86400, "ns2.localdomain.");
if (result != ISC_R_SUCCESS)
return (ISC_R_FAILURE);
return (ISC_R_SUCCESS);
}
/*
* This zone does not support zone transfer, so allnodes() is NULL. There
* is no database specific data, so create() and destroy() are NULL.
*/
static dns_sdbmethods_t timedb_methods = {
timedb_lookup,
timedb_authority,
NULL, /* allnodes */
NULL, /* create */
NULL, /* destroy */
NULL /* lookup2 */
};
/*
* Wrapper around dns_sdb_register().
*/
isc_result_t
timedb_init(void) {
unsigned int flags;
flags = DNS_SDBFLAG_RELATIVEOWNER | DNS_SDBFLAG_RELATIVERDATA;
return (dns_sdb_register("time", &timedb_methods, NULL, flags,
ns_g_mctx, &timedb));
}
/*
* Wrapper around dns_sdb_unregister().
*/
void
timedb_clear(void) {
if (timedb != NULL)
dns_sdb_unregister(&timedb);
}
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