/*
 * Copyright (C) 2002 Stichting NLnet, Netherlands, stichting@nlnet.nl.
 * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
 *
 * SPDX-License-Identifier: MPL-2.0
 *
 * 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 https://mozilla.org/MPL/2.0/.
 *
 * See the COPYRIGHT file distributed with this work for additional
 * information regarding copyright ownership.
 */

/*
 * Copyright (C) 1999-2001, 2016  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/.
 */

#ifdef DLZ_STUB
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <isc/mem.h>
#include <isc/print.h>
#include <isc/result.h>
#include <isc/util.h>

#include <dns/log.h>
#include <dns/result.h>
#include <dns/sdlz.h>

#include <dlz/dlz_stub_driver.h>
#include <named/globals.h>

static dns_sdlzimplementation_t *dlz_stub = NULL;

typedef struct config_data {
	char *myzone;
	char *myname;
	char *myip;
	isc_mem_t *mctx;
} config_data_t;

/*
 * SDLZ methods
 */

static isc_result_t
stub_dlz_allnodes(const char *zone, void *driverarg, void *dbdata,
		  dns_sdlzallnodes_t *allnodes) {
	config_data_t *cd;
	isc_result_t result;

	UNUSED(zone);
	UNUSED(driverarg);

	cd = (config_data_t *)dbdata;

	result = dns_sdlz_putnamedrr(allnodes, cd->myname, "soa", 86400,
				     "web root.localhost. "
				     "0 28800 7200 604800 86400");
	if (result != ISC_R_SUCCESS) {
		return (ISC_R_FAILURE);
	}
	result = dns_sdlz_putnamedrr(allnodes, "ns", "ns", 86400, cd->myname);
	if (result != ISC_R_SUCCESS) {
		return (ISC_R_FAILURE);
	}
	result = dns_sdlz_putnamedrr(allnodes, cd->myname, "a", 1, cd->myip);
	if (result != ISC_R_SUCCESS) {
		return (ISC_R_FAILURE);
	}
	return (ISC_R_SUCCESS);
}

static isc_result_t
stub_dlz_allowzonexfr(void *driverarg, void *dbdata, const char *name,
		      const char *client) {
	config_data_t *cd;

	UNUSED(driverarg);
	UNUSED(client);

	cd = (config_data_t *)dbdata;

	if (strcmp(name, cd->myname) == 0) {
		return (ISC_R_SUCCESS);
	}
	return (ISC_R_NOTFOUND);
}

static isc_result_t
stub_dlz_authority(const char *zone, void *driverarg, void *dbdata,
		   dns_sdlzlookup_t *lookup) {
	isc_result_t result;
	config_data_t *cd;

	UNUSED(driverarg);

	cd = (config_data_t *)dbdata;

	if (strcmp(zone, cd->myzone) == 0) {
		result = dns_sdlz_putsoa(lookup, cd->myname, "root.localhost.",
					 0);
		if (result != ISC_R_SUCCESS) {
			return (ISC_R_FAILURE);
		}

		result = dns_sdlz_putrr(lookup, "ns", 86400, cd->myname);
		if (result != ISC_R_SUCCESS) {
			return (ISC_R_FAILURE);
		}

		return (ISC_R_SUCCESS);
	}
	return (ISC_R_NOTFOUND);
}

static isc_result_t
stub_dlz_findzonedb(void *driverarg, void *dbdata, const char *name,
		    dns_clientinfomethods_t *methods,
		    dns_clientinfo_t *clientinfo) {
	config_data_t *cd;

	UNUSED(driverarg);
	UNUSED(methods);
	UNUSED(clientinfo);

	cd = (config_data_t *)dbdata;

	/* Write info message to log */
	isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ,
		      ISC_LOG_DEBUG(2), "dlz_stub findzone looking for '%s'",
		      name);

	if (strcmp(cd->myzone, name) == 0) {
		return (ISC_R_SUCCESS);
	} else {
		return (ISC_R_NOTFOUND);
	}
}

static isc_result_t
stub_dlz_lookup(const char *zone, const char *name, void *driverarg,
		void *dbdata, dns_sdlzlookup_t *lookup,
		dns_clientinfomethods_t *methods,
		dns_clientinfo_t *clientinfo) {
	isc_result_t result;
	config_data_t *cd;

	UNUSED(zone);
	UNUSED(driverarg);
	UNUSED(methods);
	UNUSED(clientinfo);

	cd = (config_data_t *)dbdata;

	if (strcmp(name, cd->myname) == 0) {
		result = dns_sdlz_putrr(lookup, "a", 1, cd->myip);
		if (result != ISC_R_SUCCESS) {
			return (ISC_R_FAILURE);
		}

		return (ISC_R_SUCCESS);
	}
	return (ISC_R_FAILURE);
}

static isc_result_t
stub_dlz_create(const char *dlzname, unsigned int argc, char *argv[],
		void *driverarg, void **dbdata) {
	config_data_t *cd;

	UNUSED(driverarg);

	if (argc < 4) {
		return (ISC_R_FAILURE);
	}
	/*
	 * Write info message to log
	 */
	isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ,
		      ISC_LOG_INFO,
		      "Loading '%s' using DLZ_stub driver. "
		      "Zone: %s, Name: %s IP: %s",
		      dlzname, argv[1], argv[2], argv[3]);

	cd = isc_mem_get(named_g_mctx, sizeof(config_data_t));
	if ((cd) == NULL) {
		return (ISC_R_NOMEMORY);
	}

	memset(cd, 0, sizeof(config_data_t));

	cd->myzone = isc_mem_strdup(named_g_mctx, argv[1]);

	cd->myname = isc_mem_strdup(named_g_mctx, argv[2]);

	cd->myip = isc_mem_strdup(named_g_mctx, argv[3]);

	isc_mem_attach(named_g_mctx, &cd->mctx);

	*dbdata = cd;

	return (ISC_R_SUCCESS);
}

static void
stub_dlz_destroy(void *driverarg, void *dbdata) {
	config_data_t *cd;
	isc_mem_t *mctx;

	UNUSED(driverarg);

	cd = (config_data_t *)dbdata;

	/*
	 * Write debugging message to log
	 */
	isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ,
		      ISC_LOG_DEBUG(2), "Unloading DLZ_stub driver.");

	isc_mem_free(named_g_mctx, cd->myzone);
	isc_mem_free(named_g_mctx, cd->myname);
	isc_mem_free(named_g_mctx, cd->myip);
	mctx = cd->mctx;
	isc_mem_putanddetach(&mctx, cd, sizeof(config_data_t));
}

static dns_sdlzmethods_t dlz_stub_methods = {
	stub_dlz_create,
	stub_dlz_destroy,
	stub_dlz_findzonedb,
	stub_dlz_lookup,
	stub_dlz_authority,
	stub_dlz_allnodes,
	stub_dlz_allowzonexfr,
	NULL,
	NULL,
	NULL,
	NULL,
	NULL,
	NULL,
	NULL,
};

/*%
 * Wrapper around dns_sdlzregister().
 */
isc_result_t
dlz_stub_init(void) {
	isc_result_t result;

	/*
	 * Write debugging message to log
	 */
	isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ,
		      ISC_LOG_DEBUG(2), "Registering DLZ_stub driver.");

	result = dns_sdlzregister("dlz_stub", &dlz_stub_methods, NULL,
				  DNS_SDLZFLAG_RELATIVEOWNER |
					  DNS_SDLZFLAG_RELATIVERDATA,
				  named_g_mctx, &dlz_stub);
	if (result != ISC_R_SUCCESS) {
		UNEXPECTED_ERROR(__FILE__, __LINE__,
				 "dns_sdlzregister() failed: %s",
				 isc_result_totext(result));
		result = ISC_R_UNEXPECTED;
	}

	return (result);
}

/*
 * Wrapper around dns_sdlzunregister().
 */
void
dlz_stub_clear(void) {
	/*
	 * Write debugging message to log
	 */
	isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_DLZ,
		      ISC_LOG_DEBUG(2), "Unregistering DLZ_stub driver.");

	if (dlz_stub != NULL) {
		dns_sdlzunregister(&dlz_stub);
	}
}

#endif /* ifdef DLZ_STUB */