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meshdesktopmultiplex.js
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/**
* @description MeshCentral remote desktop multiplexor
* @author Ylian Saint-Hilaire
* @copyright Intel Corporation 2018-2021
* @license Apache-2.0
* @version v0.0.1
*/
/*jslint node: true */
/*jshint node: true */
/*jshint strict:false */
/*jshint -W097 */
/*jshint esversion: 6 */
"use strict";
/*
--- KVM Commands ---
MNG_KVM_NOP = 0,
MNG_KVM_KEY = 1,
MNG_KVM_MOUSE = 2,
MNG_KVM_MOUSE_CURSOR = 88,
MNG_KVM_MOUSE_MOVE = 89,
MNG_KVM_PICTURE = 3,
MNG_KVM_COPY = 4,
MNG_KVM_COMPRESSION = 5,
MNG_KVM_REFRESH = 6,
MNG_KVM_SCREEN = 7,
MNG_KVM_PAUSE = 8,
MNG_TERMTEXT = 9,
MNG_CTRLALTDEL = 10,
MNG_KVM_GET_DISPLAYS = 11,
MNG_KVM_SET_DISPLAY = 12,
MNG_KVM_FRAME_RATE_TIMER = 13,
MNG_KVM_INIT_TOUCH = 14,
MNG_KVM_TOUCH = 15,
MNG_KVM_CONNECTCOUNT = 16,
MNG_KVM_MESSAGE = 17,
MNG_ECHO = 21,
MNG_JUMBO = 27,
MNG_GETDIR = 50,
MNG_FILEMOVE = 51,
MNG_FILEDELETE = 52,
MNG_FILECOPY = 53,
MNG_FILECREATEDIR = 54,
MNG_FILETRANSFER = 55,
MNG_FILEUPLOAD = 56,
MNG_FILESEARCH = 57,
MNG_FILETRANSFER2 = 58,
MNG_KVM_DISCONNECT = 59,
MNG_GETDIR2 = 60, // Same as MNG_GETDIR but with date/time.
MNG_FILEUPLOAD2 = 61, // Used for slot based fast upload.
MNG_FILEDELETEREC = 62, // Same as MNG_FILEDELETE but recursive
MNG_USERCONSENT = 63, // Used to notify management console of user consent state
MNG_DEBUG = 64, // Debug/Logging Message for ILibRemoteLogging
MNG_ERROR = 65,
MNG_ENCAPSULATE_AGENT_COMMAND = 70,
MNG_KVM_DISPLAY_INFO = 82
*/
function CreateDesktopMultiplexor(parent, domain, nodeid, func) {
var obj = {};
obj.nodeid = nodeid;
obj.parent = parent;
obj.agent = null; // Reference to the connection object that is the agent.
obj.viewers = []; // Array of references to all viewers.
obj.viewersOverflowCount = 0; // Number of viewers currently in overflow state.
obj.width = 0; // Current width of the display in pixels.
obj.height = 0; // Current height of the display in pixels.
obj.swidth = 0; // Current width of the display in tiles.
obj.sheight = 0; // Current height of the display in tiles.
obj.screen = null; // The main screen, (x * y) --> tile index. Indicates this image is covering each tile on the screen.
obj.counter = 1; // The main counter, used as index for the obj.images table when now images come in.
obj.imagesCount = 0; // Total number of images in the obj.images table.
obj.imagesCounters = {}; // Main table of indexes --> tile count, the number of tiles still using this image.
obj.images = {}; // Main table of indexes --> image data object.
obj.lastScreenSizeCmd = null; // Pointer to the last screen size command from the agent.
obj.lastScreenSizeCounter = 0; // Index into the image table of the screen size command, this is generally also the first command.
obj.lastConsoleMessage = null; // Last agent console message.
obj.firstData = null; // Index in the image table of the first image in the table, generally this points to the display resolution command.
obj.lastData = null; // Index in the images table of the last image in the table.
obj.lastDisplayInfoData = null; // Pointer to the last display information command from the agent (Number of displays).
obj.lastDisplayLocationData = null; // Pointer to the last display location and size command from the agent.
obj.desktopPaused = true; // Current desktop pause state, it's true if all viewers are paused.
obj.imageCompression = 50; // Current image compression, this is the highest value of all viewers.
obj.imageScaling = 1024; // Current image scaling, this is the highest value of all viewers.
obj.imageFrameRate = 50; // Current framerate setting, this is the lowest values of all viewers.
obj.protocolOptions = null; // Set to the protocol options of the first viewer that connected.
obj.viewerConnected = false; // Set to true if one viewer attempted to connect to the agent.
obj.recordingFile = null; // Present if we are recording to file.
obj.recordingFileSize = 0; // Current size of the recording file.
obj.recordingFileWriting = false; // Set to true is we are in the process if writing to the recording file.
obj.startTime = null; // Starting time of the multiplex session.
obj.userIds = []; // List of userid's that have intertracted with this session.
// Accounting
parent.trafficStats.desktopMultiplex.sessions++;
// Add an agent or viewer
obj.addPeer = function (peer) {
if (obj.viewers == null) { parent.parent.debug('relay', 'DesktopRelay: Error, addingPeer on disposed session'); return; }
if (peer.req == null) return; // This peer is already disposed, don't add it.
if (peer.req.query.browser) {
//console.log('addPeer-viewer', obj.nodeid);
// Setup the viewer
if (obj.viewers.indexOf(peer) >= 0) return true;
obj.viewers.push(peer);
peer.desktopPaused = true;
peer.imageCompression = 30;
peer.imageScaling = 1024;
peer.imageFrameRate = 100;
peer.lastImageNumberSent = null;
peer.dataPtr = obj.firstData;
peer.sending = false;
peer.overflow = false;
peer.sendQueue = [];
peer.paused = false;
// Add the user to the userids list if needed
if ((peer.user != null) && (obj.userIds.indexOf(peer.user._id) == -1)) { obj.userIds.push(peer.user._id); }
// Setup slow relay is requested. This will show down sending any data to this viewer.
if ((peer.req.query.slowrelay != null)) {
var sr = null;
try { sr = parseInt(peer.req.query.slowrelay); } catch (ex) { }
if ((typeof sr == 'number') && (sr > 0) && (sr < 1000)) { peer.slowRelay = sr; }
}
// Indicated we are connected
obj.sendToViewer(peer, obj.recordingFile ? 'cr' : 'c');
// If the agent sent display information or console message, send it to the viewer
if (obj.lastDisplayInfoData != null) { obj.sendToViewer(peer, obj.lastDisplayInfoData); }
if (obj.lastDisplayLocationData != null) { obj.sendToViewer(peer, obj.lastDisplayLocationData); }
if (obj.lastConsoleMessage != null) { obj.sendToViewer(peer, obj.lastConsoleMessage); }
// Log joining the multiplex session
if (obj.startTime != null) {
var event = { etype: 'relay', action: 'relaylog', domain: domain.id, nodeid: obj.nodeid, userid: peer.user._id, username: peer.user.name, msgid: 4, msg: "Joined desktop multiplex session", protocol: 2 };
parent.parent.DispatchEvent(['*', obj.nodeid, peer.user._id, obj.meshid], obj, event);
}
// Send an updated list of all peers to all viewers
obj.sendSessionMetadata();
} else {
//console.log('addPeer-agent', obj.nodeid);
if (obj.agent != null) { parent.parent.debug('relay', 'DesktopRelay: Error, duplicate agent connection'); return false; }
// Setup the agent
obj.agent = peer;
peer.sending = false;
peer.overflow = false;
peer.sendQueue = [];
peer.paused = false;
// Indicated we are connected and send connection options and protocol if needed
obj.sendToAgent(obj.recordingFile?'cr':'c');
if (obj.viewerConnected == true) {
if (obj.protocolOptions != null) { obj.sendToAgent(JSON.stringify(obj.protocolOptions)); } // Send connection options
obj.sendToAgent('2'); // Send remote desktop connect
}
}
// Log multiplex session start
if ((obj.agent != null) && (obj.viewers.length > 0) && (obj.startTime == null)) {
var event = { etype: 'relay', action: 'relaylog', domain: domain.id, nodeid: obj.nodeid, userid: obj.viewers[0].user._id, username: obj.viewers[0].user.name, msgid: 6, msg: "Started desktop multiplex session", protocol: 2 };
parent.parent.DispatchEvent(['*', obj.nodeid, obj.viewers[0].user._id, obj.meshid], obj, event);
obj.startTime = Date.now();
}
return true;
}
// Remove an agent or viewer
// Return true if this multiplexor is no longer needed.
obj.removePeer = function (peer) {
if (obj.viewers == null) return;
if (peer == obj.agent) {
//console.log('removePeer-agent', obj.nodeid);
// Clean up the agent
obj.agent = null;
// Agent has disconnected, disconnect everyone.
if (obj.viewers != null) { for (var i in obj.viewers) { obj.viewers[i].close(); } }
dispose();
return true;
} else {
//console.log('removePeer-viewer', obj.nodeid);
// Remove a viewer
if (obj.viewers != null) {
var i = obj.viewers.indexOf(peer);
if (i == -1) return false;
obj.viewers.splice(i, 1);
}
// Resume flow control if this was the peer that was limiting traffic (because it was the fastest one).
if (peer.overflow == true) {
obj.viewersOverflowCount--;
peer.overflow = false;
if ((obj.viewersOverflowCount < obj.viewers.length) && (obj.recordingFileWriting == false) && obj.agent && (obj.agent.paused == true)) { obj.agent.paused = false; obj.agent.ws._socket.resume(); }
}
// Aggressive clean up of the viewer
delete peer.desktopPaused;
delete peer.imageCompression;
delete peer.imageScaling;
delete peer.imageFrameRate;
delete peer.lastImageNumberSent;
delete peer.dataPtr;
delete peer.sending;
delete peer.overflow;
delete peer.sendQueue;
// Log leaving the multiplex session
if (obj.startTime != null) {
var event = { etype: 'relay', action: 'relaylog', domain: domain.id, nodeid: obj.nodeid, userid: peer.user._id, username: peer.user.name, msgid: 5, msg: "Left the desktop multiplex session", protocol: 2 };
parent.parent.DispatchEvent(['*', obj.nodeid, peer.user._id, obj.meshid], obj, event);
}
// If this is the last viewer, disconnect the agent
if ((obj.viewers != null) && (obj.viewers.length == 0) && (obj.agent != null)) { obj.agent.close(); dispose(); return true; }
// Send an updated list of all peers to all viewers
obj.sendSessionMetadata();
}
return false;
}
// Clean up ourselves
function dispose() {
if (obj.viewers == null) return;
//console.log('dispose', obj.nodeid);
delete obj.viewers;
delete obj.imagesCounters;
delete obj.images;
// Close the recording file if needed
if (obj.recordingFile != null) {
// Compute session length
if (obj.startTime != null) { obj.sessionStart = obj.startTime; obj.sessionLength = Math.round((Date.now() - obj.startTime) / 1000); }
// Write the last record of the recording file
var rf = obj.recordingFile;
delete obj.recordingFile;
recordingEntry(rf.fd, 3, 0, 'MeshCentralMCREC', function (fd, filename) {
parent.parent.fs.close(fd);
// Now that the recording file is closed, check if we need to index this file.
if (domain.sessionrecording.index !== false) { parent.parent.certificateOperations.acceleratorPerformOperation('indexMcRec', filename); }
// Add a event entry about this recording
var basefile = parent.parent.path.basename(filename);
var event = { etype: 'relay', action: 'recording', domain: domain.id, nodeid: obj.nodeid, msgid: 7, mshArgs: [obj.sessionLength], msg: "Finished recording session" + (obj.sessionLength ? (', ' + obj.sessionLength + ' second(s)') : ''), filename: basefile, size: obj.recordingFileSize, protocol: 2, icon: obj.icon, name: obj.name, meshid: obj.meshid, userids: obj.userIds, multiplex: true };
var mesh = parent.meshes[obj.meshid];
if (mesh != null) { event.meshname = mesh.name; }
if (obj.sessionStart) { event.startTime = obj.sessionStart; event.lengthTime = obj.sessionLength; }
parent.parent.DispatchEvent(['*', 'recording', obj.nodeid, obj.meshid], obj, event);
cleanUpRecordings();
}, rf.filename);
}
// Log end of multiplex session
if (obj.startTime != null) {
var event = { etype: 'relay', action: 'relaylog', domain: domain.id, nodeid: obj.nodeid, msgid: 8, msgArgs: [Math.floor((Date.now() - obj.startTime) / 1000)], msg: "Closed desktop multiplex session" + ', ' + Math.floor((Date.now() - obj.startTime) / 1000) + ' second(s)', protocol: 2 };
parent.parent.DispatchEvent(['*', obj.nodeid, obj.meshid], obj, event);
obj.startTime = null;
}
// Send an updated list of all peers to all viewers
obj.sendSessionMetadata();
parent.parent.debug('relay', 'DesktopRelay: Disposing desktop multiplexor');
}
// Send data to the agent or queue it up for sending
obj.sendToAgent = function (data) {
if ((obj.viewers == null) || (obj.agent == null)) return;
//console.log('SendToAgent', data.length);
if (obj.agent.sending) {
obj.agent.sendQueue.push(data);
// Flow control, pause all viewers is the queue is backing up
if (obj.agent.sendQueue > 10) {
obj.agent.overflow = true;
for (var i in obj.viewers) {
var v = obj.viewers[i];
if (v.paused == false) { v.paused = true; v.ws._socket.pause(); }
}
}
} else {
obj.agent.ws.send(data, sendAgentNext);
}
}
// Send more data to the agent
function sendAgentNext() {
if ((obj.viewers == null) || (obj.agent == null)) return;
if (obj.agent.sendQueue.length > 0) {
// Send from the pending send queue
obj.agent.ws.send(obj.agent.sendQueue.shift(), sendAgentNext);
} else {
// Nothing to send
obj.agent.sending = false;
// Flow control, resume all viewers
if (obj.agent.overflow == true) {
obj.agent.overflow = false;
for (var i in obj.viewers) {
var v = obj.viewers[i];
if (v.paused == true) { v.paused = false; v.ws._socket.resume(); }
}
}
}
}
// Send the list of all users currently vieweing this session to all viewers and servers
obj.sendSessionMetadata = function () {
var allUsers = {};
if (obj.viewers != null) {
for (var i in obj.viewers) {
var v = obj.viewers[i];
if ((v.user != null) && (v.user._id != null)) {
var id = v.user._id;
if (v.guestName) { id += '/guest:' + Buffer.from(v.guestName).toString('base64'); } // If this is a guest connect, add the Base64 guest name.
if (allUsers[id] == null) { allUsers[id] = 1; } else { allUsers[id]++; }
}
}
obj.sendToAllViewers(JSON.stringify({ type: 'metadata', 'ctrlChannel': '102938', users: allUsers, startTime: obj.startTime }));
}
// Update the sessions attached the to agent
if (obj.nodeid != null) {
const xagent = parent.wsagents[obj.nodeid];
if (xagent != null) {
if (xagent.sessions == null) { xagent.sessions = {}; }
xagent.sessions.multidesk = allUsers;
xagent.updateSessions();
}
}
}
// Send this command to all viewers
obj.sendToAllViewers = function (data) {
if (obj.viewers == null) return;
for (var i in obj.viewers) { obj.sendToViewer(obj.viewers[i], data); }
}
// Send this command to all viewers
obj.sendToAllInputViewers = function (data) {
if (obj.viewers == null) return;
for (var i in obj.viewers) { if (obj.viewers[i].viewOnly != true) { obj.sendToViewer(obj.viewers[i], data); } }
}
// Send data to the viewer or queue it up for sending
obj.sendToViewer = function (viewer, data) {
if ((viewer == null) || (obj.viewers == null)) return;
//console.log('SendToViewer', data.length);
if (viewer.sending) {
viewer.sendQueue.push(data);
} else {
viewer.sending = true;
if (viewer.slowRelay) {
setTimeout(function () { try { viewer.ws.send(data, function () { sendViewerNext(viewer); }); } catch (ex) { } }, viewer.slowRelay);
} else {
try { viewer.ws.send(data, function () { sendViewerNext(viewer); }); } catch (ex) { }
}
// Flow control, pause the agent if needed
checkViewerOverflow(viewer);
}
}
// Check if a viewer is in overflow situation
function checkViewerOverflow(viewer) {
if ((viewer.overflow == true) || (obj.viewers == null)) return;
if ((viewer.sendQueue.length > 5) || ((viewer.dataPtr != null) && (viewer.dataPtr != obj.lastData))) {
viewer.overflow = true;
obj.viewersOverflowCount++;
if ((obj.viewersOverflowCount >= obj.viewers.length) && obj.agent && (obj.agent.paused == false)) { obj.agent.paused = true; obj.agent.ws._socket.pause(); }
}
}
// Check if a viewer is in underflow situation
function checkViewerUnderflow(viewer) {
if ((viewer.overflow == false) || (obj.viewers == null)) return;
if ((viewer.sendQueue.length <= 5) && ((viewer.dataPtr == null) || (viewer.dataPtr == obj.lastData))) {
viewer.overflow = false;
obj.viewersOverflowCount--;
if ((obj.viewersOverflowCount < obj.viewers.length) && (obj.recordingFileWriting == false) && obj.agent && (obj.agent.paused == true)) { obj.agent.paused = false; obj.agent.ws._socket.resume(); }
}
}
// Send more data to the viewer
function sendViewerNext(viewer) {
if ((viewer.sendQueue == null) || (obj.viewers == null)) return;
if (viewer.sendQueue.length > 0) {
// Send from the pending send queue
if (viewer.sending == false) { viewer.sending = true; }
if (viewer.slowRelay) {
setTimeout(function () { try { viewer.ws.send(viewer.sendQueue.shift(), function () { sendViewerNext(viewer); }); } catch (ex) { } }, viewer.slowRelay);
} else {
try { viewer.ws.send(viewer.sendQueue.shift(), function () { sendViewerNext(viewer); }); } catch (ex) { }
}
checkViewerOverflow(viewer);
} else {
if (viewer.dataPtr != null) {
// Send the next image
//if ((viewer.lastImageNumberSent != null) && ((viewer.lastImageNumberSent + 1) != (viewer.dataPtr))) { console.log('SVIEW-S1', viewer.lastImageNumberSent, viewer.dataPtr); } // DEBUG
var image = obj.images[viewer.dataPtr];
viewer.lastImageNumberSent = viewer.dataPtr;
//if ((image.next != null) && ((viewer.dataPtr + 1) != image.next)) { console.log('SVIEW-S2', viewer.dataPtr, image.next); } // DEBUG
viewer.dataPtr = image.next;
if (viewer.slowRelay) {
setTimeout(function () { try { viewer.ws.send(image.data, function () { sendViewerNext(viewer); }); } catch (ex) { } }, viewer.slowRelay);
} else {
try { viewer.ws.send(image.data, function () { sendViewerNext(viewer); }); } catch (ex) { }
}
// Flow control, pause the agent if needed
if (viewer.sending == false) { viewer.sending = true; }
checkViewerOverflow(viewer);
} else {
// Nothing to send
viewer.sending = false;
// Flow control, resume agent if needed
checkViewerUnderflow(viewer);
}
}
}
// Process data coming from the agent or any viewers
obj.processData = function (peer, data) {
if (obj.viewers == null) return;
if (peer == obj.agent) {
obj.recordingFileWriting = true;
recordData(true, data, function () {
if (obj.viewers == null) return;
obj.recordingFileWriting = false;
if ((obj.viewersOverflowCount < obj.viewers.length) && obj.agent && (obj.agent.paused == true)) { obj.agent.paused = false; obj.agent.ws._socket.resume(); }
obj.processAgentData(data);
});
} else {
obj.processViewerData(peer, data);
}
}
// Process incoming viewer data
obj.processViewerData = function (viewer, data) {
if (typeof data == 'string') {
if (data == '2') {
if (obj.viewerConnected == false) {
if (obj.agent != null) {
if (obj.protocolOptions != null) { obj.sendToAgent(JSON.stringify(obj.protocolOptions)); } // Send connection options
obj.sendToAgent('2'); // Send remote desktop connect
}
obj.viewerConnected = true;
}
return;
}
var json = null;
try { json = JSON.parse(data); } catch (ex) { }
if (json == null) return;
if ((json.type == 'options') && (obj.protocolOptions == null)) { obj.protocolOptions = json; }
if ((json.ctrlChannel == '102938') && (json.type == 'lock') && (viewer.viewOnly == false)) { obj.sendToAgent('{"ctrlChannel":"102938","type":"lock"}'); } // Account lock support
return;
}
//console.log('ViewerData', data.length, typeof data, data);
if ((typeof data != 'object') || (data.length < 4)) return; // Ignore all control traffic for now (WebRTC)
var command = data.readUInt16BE(0);
var cmdsize = data.readUInt16BE(2);
if (data.length != cmdsize) return; // Invalid command length
//console.log('ViewerData', data.length, command, cmdsize);
switch (command) {
case 1: // Key Events, forward to agent
if (viewer.viewOnly == false) { obj.sendToAgent(data); }
break;
case 2: // Mouse events, forward to agent
if (viewer.viewOnly == false) { obj.sendToAgent(data); }
break;
case 5: // Compression
if (data.length < 10) return;
//viewer.imageType = data[4]; // Always 1=JPEG
viewer.imageCompression = data[5];
viewer.imageScaling = data.readUInt16BE(6);
viewer.imageFrameRate = data.readUInt16BE(8);
//console.log('Viewer-Compression', viewer.imageCompression, viewer.imageScaling, viewer.imageFrameRate);
// See if this changes anything
var viewersimageCompression = null;
var viewersimageScaling = null;
var viewersimageFrameRate = null;
for (var i in obj.viewers) {
if ((viewersimageCompression == null) || (obj.viewers[i].imageCompression > viewersimageCompression)) { viewersimageCompression = obj.viewers[i].imageCompression; };
if ((viewersimageScaling == null) || (obj.viewers[i].imageScaling > viewersimageScaling)) { viewersimageScaling = obj.viewers[i].imageScaling; };
if ((viewersimageFrameRate == null) || (obj.viewers[i].imageFrameRate < viewersimageFrameRate)) { viewersimageFrameRate = obj.viewers[i].imageFrameRate; };
}
if ((obj.imageCompression != viewersimageCompression) || (obj.imageScaling != viewersimageScaling) || (obj.imageFrameRate != viewersimageFrameRate)) {
// Update and send to agent new compression settings
obj.imageCompression = viewersimageCompression;
obj.imageScaling = viewersimageScaling;
obj.imageFrameRate = viewersimageFrameRate
//console.log('Send-Agent-Compression', obj.imageCompression, obj.imageScaling, obj.imageFrameRate);
var cmd = Buffer.alloc(10);
cmd.writeUInt16BE(5, 0); // Command 5, compression
cmd.writeUInt16BE(10, 2); // Command size, 10 bytes long
cmd[4] = 1; // Image type, 1 = JPEG
cmd[5] = obj.imageCompression; // Image compression level
cmd.writeUInt16BE(obj.imageScaling, 6); // Scaling level
cmd.writeUInt16BE(obj.imageFrameRate, 8); // Frame rate timer
obj.sendToAgent(cmd);
}
break;
case 6: // Refresh, handle this on the server
//console.log('Viewer-Refresh');
viewer.dataPtr = obj.firstData; // Start over
if (viewer.sending == false) { sendViewerNext(viewer); }
break;
case 8: // Pause and unpause
if (data.length != 5) break;
var pause = data[4]; // 0 = Unpause, 1 = Pause
if (viewer.desktopPaused == (pause == 1)) break;
viewer.desktopPaused = (pause == 1);
//console.log('Viewer-' + ((pause == 1)?'Pause':'UnPause'));
var viewersPaused = true;
for (var i in obj.viewers) { if (obj.viewers[i].desktopPaused == false) { viewersPaused = false; }; }
if (viewersPaused != obj.desktopPaused) {
obj.desktopPaused = viewersPaused;
//console.log('Send-Agent-' + ((viewersPaused == true) ? 'Pause' : 'UnPause'));
data[4] = (viewersPaused == true) ? 1 : 0;
obj.sendToAgent(data);
}
break;
case 10: // CTRL-ALT-DEL, forward to agent
if (viewer.viewOnly == false) { obj.sendToAgent(data); }
break;
case 12: // SET DISPLAY, forward to agent
if (viewer.viewOnly == false) { obj.sendToAgent(data); }
break;
case 14: // Touch setup
break;
case 82: // Request display information
if (obj.lastDisplayLocationData != null) { obj.sendToAgent(obj.lastDisplayLocationData); }
break;
case 85: // Unicode Key Events, forward to agent
if (viewer.viewOnly == false) { obj.sendToAgent(data); }
break;
case 87: // Remote input lock, forward to agent
if (viewer.viewOnly == false) { obj.sendToAgent(data); }
break;
default:
console.log('Un-handled viewer command: ' + command);
break;
}
}
// Process incoming agent data
obj.processAgentData = function (data) {
if ((typeof data != 'object') || (data.length < 4)) {
if (typeof data == 'string') {
var json = null;
try { json = JSON.parse(data); } catch (ex) { }
if (json == null) return;
if (json.type == 'console') {
// This is a console message, store it and forward this to all viewers
if (json.msg != null) { obj.lastConsoleMessage = data; } else { obj.lastConsoleMessage = null; }
obj.sendToAllViewers(data);
}
// All other control messages (notably WebRTC), are ignored for now.
}
return; // Ignore all other traffic
}
const jumboData = data;
var command = data.readUInt16BE(0);
var cmdsize = data.readUInt16BE(2);
//console.log('AgentData', data.length, command, cmdsize);
if ((command == 27) && (cmdsize == 8)) {
// Jumbo packet
if (data.length >= 12) {
command = data.readUInt16BE(8);
cmdsize = data.readUInt32BE(4);
if (data.length == (cmdsize + 8)) {
data = data.slice(8, data.length);
} else {
console.log('TODO-PARTIAL-JUMBO', command, cmdsize, data.length);
return; // TODO
}
}
}
switch (command) {
case 3: // Tile, check dimentions and store
if ((data.length < 10) || (obj.lastData == null)) break;
var x = data.readUInt16BE(4), y = data.readUInt16BE(6);
var dimensions = require('image-size')(data.slice(8));
var sx = (x / 16), sy = (y / 16), sw = (dimensions.width / 16), sh = (dimensions.height / 16);
obj.counter++;
// Keep a reference to this image & how many tiles it covers
obj.images[obj.counter] = { next: null, prev: obj.lastData, data: jumboData };
obj.images[obj.lastData].next = obj.counter;
obj.lastData = obj.counter;
obj.imagesCounters[obj.counter] = (sw * sh);
obj.imagesCount++;
if (obj.imagesCount == 2000000000) { obj.imagesCount = 1; } // Loop the counter if needed
//console.log('Adding Image ' + obj.counter, x, y, dimensions.width, dimensions.height);
// Update the screen with the correct pointers.
for (var i = 0; i < sw; i++) {
for (var j = 0; j < sh; j++) {
var k = ((obj.swidth * (j + sy)) + (i + sx));
const oi = obj.screen[k];
obj.screen[k] = obj.counter;
if ((oi != null) && (--obj.imagesCounters[oi] == 0)) {
// Remove data from the link list
obj.imagesCount--;
var d = obj.images[oi];
//console.log('Removing Image', oi, obj.images[oi].prev, obj.images[oi].next);
obj.images[d.prev].next = d.next;
obj.images[d.next].prev = d.prev;
delete obj.images[oi];
delete obj.imagesCounters[oi];
// If any viewers are currently on image "oi" must be moved to "d.next"
for (var l in obj.viewers) { const v = obj.viewers[l]; if (v.dataPtr == oi) { v.dataPtr = d.next; } }
}
}
}
// Any viewer on dataPtr null, change to this image
for (var i in obj.viewers) {
const v = obj.viewers[i];
if (v.dataPtr == null) { v.dataPtr = obj.counter; if (v.sending == false) { sendViewerNext(v); } }
}
// Debug, display the link list
//var xx = '', xptr = obj.firstData;
//while (xptr != null) { xx += '>' + xptr; xptr = obj.images[xptr].next; }
//console.log('list', xx);
//console.log('images', obj.imagesCount);
break;
case 4: // Tile Copy, do nothing.
break;
case 7: // Screen Size, clear the screen state and compute the tile count
if (data.length < 8) break;
if ((obj.width === data.readUInt16BE(4)) && (obj.height === data.readUInt16BE(6))) break; // Same screen size as before, skip this.
obj.counter++;
obj.lastScreenSizeCmd = data;
obj.lastScreenSizeCounter = obj.counter;
obj.width = data.readUInt16BE(4);
obj.height = data.readUInt16BE(6);
obj.swidth = obj.width / 16;
obj.sheight = obj.height / 16;
if (Math.floor(obj.swidth) != obj.swidth) { obj.swidth = Math.floor(obj.swidth) + 1; }
if (Math.floor(obj.sheight) != obj.sheight) { obj.sheight = Math.floor(obj.sheight) + 1; }
// Reset the display
obj.screen = new Array(obj.swidth * obj.sheight);
obj.imagesCount = 0;
obj.imagesCounters = {};
obj.images = {};
obj.images[obj.counter] = { next: null, prev: null, data: data };
obj.firstData = obj.counter;
obj.lastData = obj.counter;
// Add viewers must be set to start at "obj.counter"
for (var i in obj.viewers) {
const v = obj.viewers[i];
v.dataPtr = obj.counter;
if (v.sending == false) { sendViewerNext(v); }
}
//console.log("ScreenSize", obj.width, obj.height, obj.swidth, obj.sheight, obj.swidth * obj.sheight);
break;
case 11: // GetDisplays
// Store and send this to all viewers right away
obj.lastDisplayInfoData = data;
obj.sendToAllInputViewers(data);
break;
case 12: // SetDisplay
obj.sendToAllInputViewers(data);
break;
case 14: // KVM_INIT_TOUCH
break;
case 15: // KVM_TOUCH
break;
case 16: // MNG_KVM_CONNECTCOUNT
break;
case 17: // MNG_KVM_MESSAGE
// Send this to all viewers right away
obj.sendToAllViewers(data);
break;
case 65: // Alert
// Send this to all viewers right away
obj.sendToAllViewers(data);
break;
case 82:
// Display information
if ((data.length < 14) || (((data.length - 4) % 10) != 0)) break; // Command must be 14 bytes and have header + 10 byte for each display.
obj.lastDisplayLocationData = data;
obj.sendToAllInputViewers(data);
break;
case 87: // MNG_KVM_INPUT_LOCK
// Send this to all viewers right away
// This will update all views on the current state of the input lock
obj.sendToAllInputViewers(data);
break;
case 88: // MNG_KVM_MOUSE_CURSOR
// Send this to all viewers right away
obj.sendToAllInputViewers(data);
break;
default:
console.log('Un-handled agent command: ' + command);
break;
}
}
function recordingSetup(domain, func) {
// Setup session recording
if ((domain.sessionrecording == true || ((typeof domain.sessionrecording == 'object') && ((domain.sessionrecording.protocols == null) || (domain.sessionrecording.protocols.indexOf(2) >= 0))))) {
// Check again to make sure we need to start recording
if (domain.sessionrecording.onlyselecteddevicegroups === true) {
var mesh = parent.meshes[obj.meshid];
if ((mesh.flags == null) || ((mesh.flags & 4) == 0)) { func(false); return; } // Do not record the session
}
var now = new Date(Date.now());
var recFilename = 'desktopSession' + ((domain.id == '') ? '' : '-') + domain.id + '-' + now.getUTCFullYear() + '-' + parent.common.zeroPad(now.getUTCMonth(), 2) + '-' + parent.common.zeroPad(now.getUTCDate(), 2) + '-' + parent.common.zeroPad(now.getUTCHours(), 2) + '-' + parent.common.zeroPad(now.getUTCMinutes(), 2) + '-' + parent.common.zeroPad(now.getUTCSeconds(), 2) + '-' + obj.nodeid.split('/')[2] + '.mcrec'
var recFullFilename = null;
if (domain.sessionrecording.filepath) {
try { parent.parent.fs.mkdirSync(domain.sessionrecording.filepath); } catch (e) { }
recFullFilename = parent.parent.path.join(domain.sessionrecording.filepath, recFilename);
} else {
try { parent.parent.fs.mkdirSync(parent.parent.recordpath); } catch (e) { }
recFullFilename = parent.parent.path.join(parent.parent.recordpath, recFilename);
}
parent.parent.fs.open(recFullFilename, 'w', function (err, fd) {
if (err != null) {
parent.parent.debug('relay', 'Relay: Unable to record to file: ' + recFullFilename);
func(false);
return;
}
// Write the recording file header
parent.parent.debug('relay', 'Relay: Started recoding to file: ' + recFullFilename);
var metadata = { magic: 'MeshCentralRelaySession', ver: 1, nodeid: obj.nodeid, meshid: obj.meshid, time: new Date().toLocaleString(), protocol: 2, devicename: obj.name, devicegroup: obj.meshname };
var firstBlock = JSON.stringify(metadata);
recordingEntry(fd, 1, 0, firstBlock, function () {
obj.recordingFile = { fd: fd, filename: recFullFilename };
obj.recordingFileWriting = false;
func(true);
});
});
} else {
func(false);
}
}
// Record data to the recording file
function recordData(isAgent, data, func) {
try {
if (obj.recordingFile != null) {
// Write data to recording file
recordingEntry(obj.recordingFile.fd, 2, (isAgent ? 0 : 2), data, function () { func(data); });
} else {
func(data);
}
} catch (ex) { console.log(ex); }
}
// Record a new entry in a recording log
function recordingEntry(fd, type, flags, data, func, tag) {
try {
if (typeof data == 'string') {
// String write
var blockData = Buffer.from(data), header = Buffer.alloc(16); // Header: Type (2) + Flags (2) + Size(4) + Time(8)
header.writeInt16BE(type, 0); // Type (1 = Header, 2 = Network Data)
header.writeInt16BE(flags, 2); // Flags (1 = Binary, 2 = User)
header.writeInt32BE(blockData.length, 4); // Size
header.writeIntBE(new Date(), 10, 6); // Time
var block = Buffer.concat([header, blockData]);
parent.parent.fs.write(fd, block, 0, block.length, function () { func(fd, tag); });
obj.recordingFileSize += block.length;
} else {
// Binary write
var header = Buffer.alloc(16); // Header: Type (2) + Flags (2) + Size(4) + Time(8)
header.writeInt16BE(type, 0); // Type (1 = Header, 2 = Network Data)
header.writeInt16BE(flags | 1, 2); // Flags (1 = Binary, 2 = User)
header.writeInt32BE(data.length, 4); // Size
header.writeIntBE(new Date(), 10, 6); // Time
var block = Buffer.concat([header, data]);
parent.parent.fs.write(fd, block, 0, block.length, function () { func(fd, tag); });
obj.recordingFileSize += block.length;
}
} catch (ex) { console.log(ex); func(fd, tag); }
}
// If there is a recording quota, remove any old recordings if needed
function cleanUpRecordings() {
if ((parent.cleanUpRecordingsActive !== true) && domain.sessionrecording && ((typeof domain.sessionrecording.maxrecordings == 'number') || (typeof domain.sessionrecording.maxrecordingsizemegabytes == 'number'))) {
parent.cleanUpRecordingsActive = true;
setTimeout(function () {
var recPath = null, fs = require('fs');
if (domain.sessionrecording.filepath) { recPath = domain.sessionrecording.filepath; } else { recPath = parent.parent.recordpath; }
fs.readdir(recPath, function (err, files) {
if ((err != null) || (files == null)) { delete parent.cleanUpRecordingsActive; return; }
var recfiles = [];
for (var i in files) {
if (files[i].endsWith('.mcrec')) {
var j = files[i].indexOf('-');
if (j > 0) { recfiles.push({ n: files[i], r: files[i].substring(j + 1), s: fs.statSync(parent.parent.path.join(recPath, files[i])).size }); }
}
}
recfiles.sort(function (a, b) { if (a.r < b.r) return 1; if (a.r > b.r) return -1; return 0; });
var totalFiles = 0, totalSize = 0;
for (var i in recfiles) {
var overQuota = false;
if ((typeof domain.sessionrecording.maxrecordings == 'number') && (totalFiles >= domain.sessionrecording.maxrecordings)) { overQuota = true; }
else if ((typeof domain.sessionrecording.maxrecordingsizemegabytes == 'number') && (totalSize >= (domain.sessionrecording.maxrecordingsizemegabytes * 1048576))) { overQuota = true; }
if (overQuota) { fs.unlinkSync(parent.parent.path.join(recPath, recfiles[i].n)); }
totalFiles++;
totalSize += recfiles[i].s;
}
delete parent.cleanUpRecordingsActive;
});
});
}
}
// Get node information
parent.db.Get(nodeid, function (err, nodes) {
if ((err != null) || (nodes.length != 1)) { func(null); return; }
obj.meshid = nodes[0].meshid;
obj.icon = nodes[0].icon;
obj.name = nodes[0].name;
recordingSetup(domain, function () { func(obj); });
});
return obj;
}
function checkDeviceSharePublicIdentifier(parent, domain, nodeid, pid, func) {
// Check the public id
parent.db.GetAllTypeNodeFiltered([nodeid], domain.id, 'deviceshare', null, function (err, docs) {
if ((err != null) || (docs.length == 0)) { func(false); return; }
// Search for the device share public identifier
var found = false;
for (var i = 0; i < docs.length; i++) { if (docs[i].publicid == pid) { found = true; } }
func(found);
});
}
module.exports.CreateMeshRelay = function (parent, ws, req, domain, user, cookie) {
if ((cookie != null) && (typeof cookie.nid == 'string') && (typeof cookie.pid == 'string')) {
checkDeviceSharePublicIdentifier(parent, domain, cookie.nid, cookie.pid, function (result) {
// If the identifier if not found, close the connection
if (result == false) { try { ws.close(); } catch (e) { } return; }
// Public device sharing identifier found, continue as normal.
CreateMeshRelayEx(parent, ws, req, domain, user, cookie);
});
} else {
CreateMeshRelayEx(parent, ws, req, domain, user, cookie);
}
}
// If we are in multi-server mode, the desktop multiplexor needs to be created on the server with the agent connected to it.
// So, if the agent is connected to a different server, just relay the connection to that server
function CreateMeshRelayEx(parent, ws, req, domain, user, cookie) {
// Do validation work
if (cookie) {
if ((typeof cookie.expire == 'number') && (cookie.expire <= Date.now())) { delete req.query.nodeid; }
else if (typeof cookie.nid == 'string') { req.query.nodeid = cookie.nid; }
}
if ((req.query.nodeid == null) || (req.query.p != '2') || (req.query.id == null) || (domain == null)) { try { ws.close(); } catch (e) { } return; } // Not is not a valid remote desktop connection.
// Check routing if in multi-server mode
var nodeid = req.query.nodeid;
if (parent.parent.multiServer != null) {
const routing = parent.parent.GetRoutingServerIdNotSelf(nodeid, 1); // 1 = MeshAgent routing type
if (routing == null) {
// No need to relay the connection to a different server
return CreateMeshRelayEx2(parent, ws, req, domain, user, cookie);
} else {
// We must relay the connection to a different server
return parent.parent.multiServer.createPeerRelay(ws, req, routing.serverid, req.session.userid);
}
} else {
// No need to relay the connection to a different server
return CreateMeshRelayEx2(parent, ws, req, domain, user, cookie);
}
}
function CreateMeshRelayEx2(parent, ws, req, domain, user, cookie) {
const currentTime = Date.now();
var obj = {};
obj.ws = ws;
obj.ws.me = obj;
obj.id = req.query.id;
obj.nodeid = req.query.nodeid;
obj.user = user;
obj.ruserid = null;
obj.req = req; // Used in multi-server.js
obj.viewOnly = ((cookie != null) && (cookie.vo == 1)); // set view only mode
// If the domain has remote desktop viewonly set, force everyone to be in viewonly mode.
if ((typeof domain.desktop == 'object') && (domain.desktop.viewonly == true)) { obj.viewOnly = true; }
// Setup traffic accounting
if (parent.trafficStats.desktopMultiplex == null) { parent.trafficStats.desktopMultiplex = { connections: 1, sessions: 0, in: 0, out: 0 }; } else { parent.trafficStats.desktopMultiplex.connections++; }
ws._socket.bytesReadEx = 0;
ws._socket.bytesWrittenEx = 0;
// Setup subscription for desktop sharing public identifier
// If the identifier is removed, drop the connection
if ((cookie != null) && (typeof cookie.pid == 'string')) {
obj.pid = cookie.pid;
obj.guestName = cookie.gn;
parent.parent.AddEventDispatch([obj.nodeid], obj);
obj.HandleEvent = function (source, event, ids, id) { if ((event.action == 'removedDeviceShare') && (obj.pid == event.publicid)) { obj.close(); } }
}
// Check relay authentication
if ((user == null) && (obj.req.query != null) && (obj.req.query.rauth != null)) {
const rcookie = parent.parent.decodeCookie(obj.req.query.rauth, parent.parent.loginCookieEncryptionKey, 240); // Cookie with 4 hour timeout
if (rcookie.ruserid != null) { obj.ruserid = rcookie.ruserid; }
if (rcookie.nodeid != null) { obj.nodeid = rcookie.nodeid; }
}
// If there is no authentication, drop this connection
if ((obj.id != null) && (obj.user == null) && (obj.ruserid == null)) { try { ws.close(); parent.parent.debug('relay', 'DesktopRelay: Connection with no authentication (' + obj.req.clientIp + ')'); } catch (e) { console.log(e); } return; }
// Relay session count (we may remove this in the future)
obj.relaySessionCounted = true;
parent.relaySessionCount++;
// Mesh Rights
const MESHRIGHT_EDITMESH = 1;
const MESHRIGHT_MANAGEUSERS = 2;
const MESHRIGHT_MANAGECOMPUTERS = 4;
const MESHRIGHT_REMOTECONTROL = 8;
const MESHRIGHT_AGENTCONSOLE = 16;
const MESHRIGHT_SERVERFILES = 32;
const MESHRIGHT_WAKEDEVICE = 64;
const MESHRIGHT_SETNOTES = 128;
const MESHRIGHT_REMOTEVIEW = 256;
// Site rights
const SITERIGHT_SERVERBACKUP = 1;
const SITERIGHT_MANAGEUSERS = 2;
const SITERIGHT_SERVERRESTORE = 4;
const SITERIGHT_FILEACCESS = 8;
const SITERIGHT_SERVERUPDATE = 16;
const SITERIGHT_LOCKED = 32;
// Clean a IPv6 address that encodes a IPv4 address
function cleanRemoteAddr(addr) { if (addr.startsWith('::ffff:')) { return addr.substring(7); } else { return addr; } }
// Disconnect this agent
obj.close = function (arg) {
if (obj.ws == null) return; // Already closed.
// Close the connection
if ((arg == 1) || (arg == null)) { try { ws.close(); parent.parent.debug('relay', 'DesktopRelay: Soft disconnect (' + obj.req.clientIp + ')'); } catch (e) { console.log(e); } } // Soft close, close the websocket
if (arg == 2) { try { ws._socket._parent.end(); parent.parent.debug('relay', 'DesktopRelay: Hard disconnect (' + obj.req.clientIp + ')'); } catch (e) { console.log(e); } } // Hard close, close the TCP socket
if (obj.relaySessionCounted) { parent.relaySessionCount--; delete obj.relaySessionCounted; }
if ((obj.deskMultiplexor != null) && (typeof obj.deskMultiplexor == 'object') && (obj.deskMultiplexor.removePeer(obj) == true)) { delete parent.desktoprelays[obj.nodeid]; }
// Aggressive cleanup
delete obj.id;
delete obj.ws;
delete obj.req;
delete obj.user;
delete obj.nodeid;
delete obj.ruserid;
delete obj.expireTimer;
delete obj.deskMultiplexor;
// Clear timers if present
if (obj.pingtimer != null) { clearInterval(obj.pingtimer); delete obj.pingtimer; }
if (obj.pongtimer != null) { clearInterval(obj.pongtimer); delete obj.pongtimer; }
// Unsubscribe
if (obj.pid != null) { parent.parent.RemoveAllEventDispatch(obj); }
};
obj.sendAgentMessage = function (command, userid, domainid) {
var rights, mesh;
if (command.nodeid == null) return false;
var user = parent.users[userid];
if (user == null) return false;
var splitnodeid = command.nodeid.split('/');
// Check that we are in the same domain and the user has rights over this node.
if ((splitnodeid[0] == 'node') && (splitnodeid[1] == domainid)) {
// Get the user object
// See if the node is connected