/*
Copyright (c) 2019-2020 Roger Light <roger@atchoo.org>

All rights reserved. This program and the accompanying materials
are made available under the terms of the Eclipse Public License v1.0
and Eclipse Distribution License v1.0 which accompany this distribution.

The Eclipse Public License is available at
   http://www.eclipse.org/legal/epl-v10.html
and the Eclipse Distribution License is available at
  http://www.eclipse.org/org/documents/edl-v10.php.

Contributors:
   Roger Light - initial implementation and documentation.
*/

#include "config.h"

#include "mosquitto_broker_internal.h"
#include "mqtt_protocol.h"
#include "memory_mosq.h"
#include "packet_mosq.h"
#include "property_mosq.h"
#include "util_mosq.h"

int send__auth(struct mosquitto_db *db, struct mosquitto *context, int reason_code, const void *auth_data, uint16_t auth_data_len)
{
	struct mosquitto__packet *packet = NULL;
	int rc;
	mosquitto_property *properties = NULL;
	int proplen, varbytes;
	uint32_t remaining_length;

	if(context->auth_method == NULL) return MOSQ_ERR_INVAL;
	if(context->protocol != mosq_p_mqtt5) return MOSQ_ERR_PROTOCOL;

	log__printf(NULL, MOSQ_LOG_DEBUG, "Sending AUTH to %s (rc%d, %s)", context->id, reason_code, context->auth_method);

	remaining_length = 1;

	rc = mosquitto_property_add_string(&properties, MQTT_PROP_AUTHENTICATION_METHOD, context->auth_method);
	if(rc){
		mosquitto_property_free_all(&properties);
		return rc;
	}

	if(auth_data != NULL && auth_data_len > 0){
		rc = mosquitto_property_add_binary(&properties, MQTT_PROP_AUTHENTICATION_DATA, auth_data, auth_data_len);
		if(rc){
			mosquitto_property_free_all(&properties);
			return rc;
		}
	}

	proplen = property__get_length_all(properties);
	varbytes = packet__varint_bytes(proplen);
	remaining_length += proplen + varbytes;

	if(packet__check_oversize(context, remaining_length)){
		mosquitto_property_free_all(&properties);
		mosquitto__free(packet);
		return MOSQ_ERR_OVERSIZE_PACKET;
	}

	packet = mosquitto__calloc(1, sizeof(struct mosquitto__packet));
	if(!packet) return MOSQ_ERR_NOMEM;

	packet->command = CMD_AUTH;
	packet->remaining_length = remaining_length;

	rc = packet__alloc(packet);
	if(rc){
		mosquitto_property_free_all(&properties);
		mosquitto__free(packet);
		return rc;
	}
	packet__write_byte(packet, reason_code);
	property__write_all(packet, properties, true);
	mosquitto_property_free_all(&properties);

	return packet__queue(context, packet);
}