/*

Copyright (c) 2009-2021 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 2.0

and Eclipse Distribution License v1.0 which accompany this distribution.

The Eclipse Public License is available at

   https://www.eclipse.org/legal/epl-2.0/

and the Eclipse Distribution License is available at

  http://www.eclipse.org/org/documents/edl-v10.php.

SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause

Contributors:

   Roger Light - initial implementation and documentation.

*/

#include "config.h"

#include <assert.h>

#include <string.h>

#ifdef WITH_BROKER

#  include "mosquitto_broker_internal.h"

#  include "sys_tree.h"

#endif

#include "logging_mosq.h"

#include "mosquitto.h"

#include "mosquitto_internal.h"

#include "mosquitto/mqtt_protocol.h"

#include "packet_mosq.h"

#include "property_mosq.h"

#include "send_mosq.h"

int send__connect(struct mosquitto *mosq, uint16_t keepalive, bool clean_session, const mosquitto_property *properties)

{

  struct mosquitto__packet *packet = NULL;

  uint32_t payloadlen;

  uint8_t will = 0;

  uint8_t byte;

  int rc;

  uint8_t version;

  char *clientid, *username, *password;

  uint32_t headerlen;

  uint32_t proplen = 0, varbytes;

  mosquitto_property *local_props = NULL;

  uint16_t receive_maximum;

  assert(mosq);

  if(mosq->protocol == mosq_p_mqtt31 && !mosq->id){

    return MOSQ_ERR_PROTOCOL;

  }

#if defined(WITH_BROKER) && defined(WITH_BRIDGE)

  if(mosq->bridge){

    clientid = mosq->bridge->remote_clientid;

    username = mosq->bridge->remote_username;

    password = mosq->bridge->remote_password;

  }else{

    clientid = mosq->id;

    username = mosq->username;

    password = mosq->password;

  }

#else

  clientid = mosq->id;

  username = mosq->username;

  password = mosq->password;

#endif

  if(mosq->protocol == mosq_p_mqtt5){

    /* Generate properties from options */

    if(!mosquitto_property_read_int16(properties, MQTT_PROP_RECEIVE_MAXIMUM, &receive_maximum, false)){

      rc = mosquitto_property_add_int16(&local_props, MQTT_PROP_RECEIVE_MAXIMUM, mosq->msgs_in.inflight_maximum);

      if(rc){

        return rc;

      }

    }else{

      mosq->msgs_in.inflight_maximum = receive_maximum;

      mosq->msgs_in.inflight_quota = receive_maximum;

    }

    version = MQTT_PROTOCOL_V5;

    headerlen = 10;

    proplen = 0;

    proplen += mosquitto_property_get_length_all(properties);

    proplen += mosquitto_property_get_length_all(local_props);

    varbytes = mosquitto_varint_bytes(proplen);

    headerlen += proplen + varbytes;

  }else if(mosq->protocol == mosq_p_mqtt311){

    version = MQTT_PROTOCOL_V311;

    headerlen = 10;

  }else if(mosq->protocol == mosq_p_mqtt31){

    version = MQTT_PROTOCOL_V31;

    headerlen = 12;

  }else{

    return MOSQ_ERR_INVAL;

  }

  if(clientid){

    payloadlen = (uint32_t)(2U+strlen(clientid));

  }else{

    payloadlen = 2U;

  }

#ifdef WITH_BROKER

  if(mosq->will && (mosq->bridge == NULL || mosq->bridge->notifications_local_only == false)){

#else

  if(mosq->will){

#endif

    will = 1;

    assert(mosq->will->msg.topic);

    payloadlen += (uint32_t)(2+strlen(mosq->will->msg.topic) + 2+(uint32_t)mosq->will->msg.payloadlen);

    if(mosq->protocol == mosq_p_mqtt5){

      payloadlen += mosquitto_property_get_remaining_length(mosq->will->properties);

    }

  }

  /* After this check we can be sure that the username and password are

   * always valid for the current protocol, so there is no need to check

   * username before checking password. */

  if(mosq->protocol == mosq_p_mqtt31 || mosq->protocol == mosq_p_mqtt311){

    if(password != NULL && username == NULL){

      return MOSQ_ERR_INVAL;

    }

  }

  if(username){

    payloadlen += (uint32_t)(2+strlen(username));

  }

  if(password){

    payloadlen += (uint32_t)(2+strlen(password));

  }

  rc = packet__alloc(&packet, CMD_CONNECT, headerlen + payloadlen);

  if(rc){

    mosquitto_FREE(packet);

    return rc;

  }

  /* Variable header */

  if(version == MQTT_PROTOCOL_V31){

    packet__write_string(packet, PROTOCOL_NAME_v31, (uint16_t)strlen(PROTOCOL_NAME_v31));

  }else{

    packet__write_string(packet, PROTOCOL_NAME, (uint16_t)strlen(PROTOCOL_NAME));

  }

#if defined(WITH_BROKER) && defined(WITH_BRIDGE)

  if(mosq->bridge && mosq->bridge->protocol_version != mosq_p_mqtt5 && mosq->bridge->try_private && mosq->bridge->try_private_accepted){

    version |= 0x80;

  }else{

  }

#endif

  packet__write_byte(packet, version);

  byte = (uint8_t)((clean_session&0x1)<<1);

  if(will){

    byte = byte | (uint8_t)(((mosq->will->msg.qos&0x3)<<3) | ((will&0x1)<<2));

    if(mosq->retain_available){

      byte |= (uint8_t)((mosq->will->msg.retain&0x1)<<5);

    }

  }

  if(username){

    byte = byte | 0x1<<7;

  }

  if(mosq->password){

    byte = byte | 0x1<<6;

  }

  packet__write_byte(packet, byte);

  packet__write_uint16(packet, keepalive);

  if(mosq->protocol == mosq_p_mqtt5){

    /* Write properties */

    packet__write_varint(packet, proplen);

    property__write_all(packet, properties, false);

    property__write_all(packet, local_props, false);

  }

  mosquitto_property_free_all(&local_props);

  /* Payload */

  if(clientid){

    packet__write_string(packet, clientid, (uint16_t)strlen(clientid));

  }else{

    packet__write_uint16(packet, 0);

  }

  if(will){

    if(mosq->protocol == mosq_p_mqtt5){

      /* Write will properties */

      property__write_all(packet, mosq->will->properties, true);

    }

    packet__write_string(packet, mosq->will->msg.topic, (uint16_t)strlen(mosq->will->msg.topic));

    packet__write_string(packet, (const char *)mosq->will->msg.payload, (uint16_t)mosq->will->msg.payloadlen);

  }

  if(username){

    packet__write_string(packet, username, (uint16_t)strlen(username));

  }

  if(password){

    packet__write_string(packet, password, (uint16_t)strlen(password));

  }

  mosq->keepalive = keepalive;

#ifdef WITH_BROKER

# ifdef WITH_BRIDGE

  log__printf(mosq, MOSQ_LOG_DEBUG, "Bridge %s sending CONNECT", SAFE_PRINT(clientid));

# endif

  metrics__int_inc(mosq_counter_mqtt_connect_sent, 1);

#else

  log__printf(mosq, MOSQ_LOG_DEBUG, "Client %s sending CONNECT", SAFE_PRINT(clientid));

#endif

  return packet__queue(mosq, packet);

}