var obj = {}

obj.parent = parent;

obj.db = db;

obj.args = args;

obj.connections = {}; // NodesID --> client array

const aedes = require('aedes')();

obj.handle = aedes.handle;

const allowedSubscriptionTopics = ['presence', 'console', 'powerAction'];

const denyError = new Error('denied');

var authError = new Error('Auth error')

authError.returnCode = 1

// Generate a username and password for MQTT login

obj.generateLogin = function (meshid, nodeid) {

const meshidsplit = meshid.split('/'), nodeidsplit = nodeid.split('/');

const xmeshid = meshidsplit[2], xnodeid = nodeidsplit[2], xdomainid = meshidsplit[1];

const username = 'MCAuth1:' + xnodeid + ':' + xmeshid + ':' + xdomainid;

const nonce = Buffer.from(parent.crypto.randomBytes(9), 'binary').toString('base64');

return { meshid: meshid, nodeid: nodeid, user: username, pass: parent.config.settings.mqtt.auth.keyid + ':' + nonce + ':' + parent.crypto.createHash('sha384').update(username + ':' + nonce + ':' + parent.config.settings.mqtt.auth.key).digest("base64") };

}

// Connection Authentication

aedes.authenticate = function (client, username, password, callback) {

obj.parent.debug('mqtt', "Authentication User:" + username + ", Pass:" + password.toString() + ", ClientID:" + client.id + ", " + client.conn.xtransport + "://" + cleanRemoteAddr(client.conn.xip));

// Parse the username and password

var usersplit = username.split(':');

var passsplit = password.toString().split(':');

if ((usersplit.length !== 4) || (passsplit.length !== 3)) { obj.parent.debug('mqtt', "Invalid user/pass format, " + client.conn.xtransport + "://" + cleanRemoteAddr(client.conn.xip)); callback(authError, null); return; }

if (usersplit[0] !== 'MCAuth1') { obj.parent.debug('mqtt', "Invalid auth method, " + client.conn.xtransport + "://" + cleanRemoteAddr(client.conn.xip)); callback(authError, null); return; }

// Check authentication

if (passsplit[0] !== parent.config.settings.mqtt.auth.keyid) { obj.parent.debug('mqtt', "Invalid auth keyid, " + client.conn.xtransport + "://" + cleanRemoteAddr(client.conn.xip)); callback(authError, null); return; }

if (parent.crypto.createHash('sha384').update(username + ':' + passsplit[1] + ':' + parent.config.settings.mqtt.auth.key).digest("base64") !== passsplit[2]) { obj.parent.debug("mqtt", "Invalid password, " + client.conn.xtransport + "://" + cleanRemoteAddr(client.conn.xip)); callback(authError, null); return; }

// Setup the identifiers

const xnodeid = usersplit[1];

var xmeshid = usersplit[2];

const xdomainid = usersplit[3];

// Check the domain

if ((typeof client.conn.xdomain == 'object') && (xdomainid != client.conn.xdomain.id)) { obj.parent.debug('mqtt', "Invalid domain connection, " + client.conn.xtransport + "://" + cleanRemoteAddr(client.conn.xip)); callback(null, false); return; }

// Convert meshid from HEX to Base64 if needed

if (xmeshid.length === 96) { xmeshid = Buffer.from(xmeshid, 'hex').toString('base64'); }

if ((xmeshid.length !== 64) || (xnodeid.length != 64)) { callback(authError, null); return; }

// Set the client nodeid and meshid

client.xdbNodeKey = 'node/' + xdomainid + '/' + xnodeid;

client.xdbMeshKey = 'mesh/' + xdomainid + '/' + xmeshid;

client.xdomainid = xdomainid;

// Check if this node exists in the database

db.Get(client.xdbNodeKey, function (err, nodes) {

if ((nodes == null) || (nodes.length != 1)) { callback(authError, null); return; } // Node does not exist

// If this device now has a different meshid, fix it here.

client.xdbMeshKey = nodes[0].meshid;

if (obj.connections[client.xdbNodeKey] == null) {

obj.connections[client.xdbNodeKey] = [client];

parent.SetConnectivityState(client.xdbMeshKey, client.xdbNodeKey, Date.now(), 16, 7, null, { name: nodes[0].name }); // Indicate this node has a MQTT connection, 7 = Present state

} else {

obj.connections[client.xdbNodeKey].push(client);

}

client.conn.parent = client;

client.conn.on('end', function () {

// client is "this.parent"

obj.parent.debug('mqtt', "Connection closed, " + this.parent.conn.xtransport + '://' + cleanRemoteAddr(this.parent.conn.xip));

// Remove this client from the connections list

if ((this.parent.xdbNodeKey != null) && (obj.connections[this.parent.xdbNodeKey] != null)) {

var clients = obj.connections[this.parent.xdbNodeKey], i = clients.indexOf(client);

if (i >= 0) {

if (clients.length == 1) {

delete obj.connections[this.parent.xdbNodeKey];

parent.ClearConnectivityState(this.parent.xdbMeshKey, this.parent.xdbNodeKey, 16, null, { name: nodes[0].name }); // Remove the MQTT connection for this node

} else { clients.splice(i, 1); }

}

}

this.parent.close();

});

callback(null, true);

});

}

// Check if a client can publish a packet

aedes.authorizeSubscribe = function (client, sub, callback) {

// Subscription control

obj.parent.debug('mqtt', "AuthorizeSubscribe \"" + sub.topic + '", ' + client.conn.xtransport + '://' + cleanRemoteAddr(client.conn.xip));

if (allowedSubscriptionTopics.indexOf(sub.topic) === -1) { sub = null; } // If not a supported subscription, deny it.

callback(null, sub); // We authorize supported topics, but will not allow agents to publish anything to other agents.

}

// Check if a client can publish a packet

aedes.authorizePublish = function (client, packet, callback) {

// Handle a published message

obj.parent.debug('mqtt', "AuthorizePublish, " + client.conn.xtransport + '://' + cleanRemoteAddr(client.conn.xip));

handleMessage(client.xdbNodeKey, client.xdbMeshKey, client.xdomainid, packet.topic, packet.payload);

// We don't accept that any client message be published, so don't call the callback.

}

// Publish a message to a specific nodeid & topic, also send this to peer servers.

obj.publish = function (nodeid, topic, message) {

// Publish this message on peer servers.

if (parent.multiServer != null) { parent.multiServer.DispatchMessage(JSON.stringify({ action: 'mqtt', nodeid: nodeid, topic: topic, message: message })); }

obj.publishNoPeers(nodeid, topic, message);

}

// Publish a message to a specific nodeid & topic, don't send to peer servers.

obj.publishNoPeers = function (nodeid, topic, message) {

// Look for any MQTT connections to send this to

var clients = obj.connections[nodeid];

if (clients == null) return;

if (typeof message == 'string') { message = Buffer.from(message); }

for (var i in clients) {

// Only publish to client that subscribe to the topic

if (clients[i].subscriptions[topic] != null) {

clients[i].publish({ cmd: 'publish', qos: 0, topic: topic, payload: message, retain: false }, function () { });

}

}

}

// Handle messages coming from clients

function handleMessage(nodeid, meshid, domainid, topic, message) {

// Handle messages here

if (topic == 'console') { parent.webserver.routeAgentCommand({ action: 'msg', type: 'console', value: message.toString(), source: 'MQTT' }, domainid, nodeid, meshid); return; } // Handle console messages

//console.log('handleMessage', nodeid, topic, message.toString());

//obj.publish(nodeid, 'echoTopic', "Echo: " + message.toString());

}

// Clean a IPv6 address that encodes a IPv4 address

function cleanRemoteAddr(addr) { if (typeof addr != 'string') { return null; } if (addr.indexOf('::ffff:') == 0) { return addr.substring(7); } else { return addr; } }

// Change a node to a new meshid

obj.changeDeviceMesh = function(nodeid, newMeshId) {

var nodes = obj.connections[nodeid];

if (nodes != null) { for (var i in nodes) { nodes[i].xdbMeshKey = newMeshId; } }

}

return obj;