MeshCentral/mqttbroker.js
2021-01-09 14:31:09 -08:00

154 lines
8.6 KiB
JavaScript

/**
* @description MQTT broker reference implementation based on AEDES
* @author Joko Banu Sastriawan, Ylian Saint-Hilaire
* @copyright Intel Corporation 2018-2021
* @license Apache-2.0
* @version v0.0.1
*/
module.exports.CreateMQTTBroker = function (parent, db, args) {
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' ];
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); // 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); // 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 }); }
}
}
// 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;
}