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Web based remote computer management and file server
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JavaScript
/*
* noVNC: HTML5 VNC client
* Copyright (C) 2018 The noVNC Authors
* Licensed under MPL 2.0 (see LICENSE.txt)
*
* See README.md for usage and integration instructions.
*
*/
import * as Log from './util/logging.js';
import { decodeUTF8 } from './util/strings.js';
import { dragThreshold } from './util/browser.js';
import EventTargetMixin from './util/eventtarget.js';
import Display from "./display.js";
import Keyboard from "./input/keyboard.js";
import Mouse from "./input/mouse.js";
import Cursor from "./util/cursor.js";
import Websock from "./websock.js";
import DES from "./des.js";
import KeyTable from "./input/keysym.js";
import XtScancode from "./input/xtscancodes.js";
import { encodings } from "./encodings.js";
import "./util/polyfill.js";
import RawDecoder from "./decoders/raw.js";
import CopyRectDecoder from "./decoders/copyrect.js";
import RREDecoder from "./decoders/rre.js";
import HextileDecoder from "./decoders/hextile.js";
import TightDecoder from "./decoders/tight.js";
import TightPNGDecoder from "./decoders/tightpng.js";
// How many seconds to wait for a disconnect to finish
const DISCONNECT_TIMEOUT = 3;
const DEFAULT_BACKGROUND = 'rgb(40, 40, 40)';
export default class RFB extends EventTargetMixin {
constructor(target, url, options) {
if (!target) {
throw new Error("Must specify target");
}
if (!url) {
throw new Error("Must specify URL");
}
super();
this._target = target;
this._url = url;
// Connection details
options = options || {};
this._rfb_credentials = options.credentials || {};
this._shared = 'shared' in options ? !!options.shared : true;
this._repeaterID = options.repeaterID || '';
this._showDotCursor = options.showDotCursor || false;
// Internal state
this._rfb_connection_state = '';
this._rfb_init_state = '';
this._rfb_auth_scheme = -1;
this._rfb_clean_disconnect = true;
// Server capabilities
this._rfb_version = 0;
this._rfb_max_version = 3.8;
this._rfb_tightvnc = false;
this._rfb_xvp_ver = 0;
this._fb_width = 0;
this._fb_height = 0;
this._fb_name = "";
this._capabilities = { power: false };
this._supportsFence = false;
this._supportsContinuousUpdates = false;
this._enabledContinuousUpdates = false;
this._supportsSetDesktopSize = false;
this._screen_id = 0;
this._screen_flags = 0;
this._qemuExtKeyEventSupported = false;
// Internal objects
this._sock = null; // Websock object
this._display = null; // Display object
this._flushing = false; // Display flushing state
this._keyboard = null; // Keyboard input handler object
this._mouse = null; // Mouse input handler object
// Timers
this._disconnTimer = null; // disconnection timer
this._resizeTimeout = null; // resize rate limiting
// Decoder states
this._decoders = {};
this._FBU = {
rects: 0,
x: 0,
y: 0,
width: 0,
height: 0,
encoding: null,
};
// Mouse state
this._mouse_buttonMask = 0;
this._mouse_arr = [];
this._viewportDragging = false;
this._viewportDragPos = {};
this._viewportHasMoved = false;
// Bound event handlers
this._eventHandlers = {
focusCanvas: this._focusCanvas.bind(this),
windowResize: this._windowResize.bind(this),
};
// main setup
Log.Debug(">> RFB.constructor");
// Create DOM elements
this._screen = document.createElement('div');
this._screen.style.display = 'flex';
this._screen.style.width = '100%';
this._screen.style.height = '100%';
this._screen.style.overflow = 'auto';
this._screen.style.background = DEFAULT_BACKGROUND;
this._canvas = document.createElement('canvas');
this._canvas.style.margin = 'auto';
// Some browsers add an outline on focus
this._canvas.style.outline = 'none';
// IE miscalculates width without this :(
this._canvas.style.flexShrink = '0';
this._canvas.width = 0;
this._canvas.height = 0;
this._canvas.tabIndex = -1;
this._screen.appendChild(this._canvas);
// Cursor
this._cursor = new Cursor();
// XXX: TightVNC 2.8.11 sends no cursor at all until Windows changes
// it. Result: no cursor at all until a window border or an edit field
// is hit blindly. But there are also VNC servers that draw the cursor
// in the framebuffer and don't send the empty local cursor. There is
// no way to satisfy both sides.
//
// The spec is unclear on this "initial cursor" issue. Many other
// viewers (TigerVNC, RealVNC, Remmina) display an arrow as the
// initial cursor instead.
this._cursorImage = RFB.cursors.none;
// populate decoder array with objects
this._decoders[encodings.encodingRaw] = new RawDecoder();
this._decoders[encodings.encodingCopyRect] = new CopyRectDecoder();
this._decoders[encodings.encodingRRE] = new RREDecoder();
this._decoders[encodings.encodingHextile] = new HextileDecoder();
this._decoders[encodings.encodingTight] = new TightDecoder();
this._decoders[encodings.encodingTightPNG] = new TightPNGDecoder();
// NB: nothing that needs explicit teardown should be done
// before this point, since this can throw an exception
try {
this._display = new Display(this._canvas);
} catch (exc) {
Log.Error("Display exception: " + exc);
throw exc;
}
this._display.onflush = this._onFlush.bind(this);
this._display.clear();
this._keyboard = new Keyboard(this._canvas);
this._keyboard.onkeyevent = this._handleKeyEvent.bind(this);
this._mouse = new Mouse(this._canvas);
this._mouse.onmousebutton = this._handleMouseButton.bind(this);
this._mouse.onmousemove = this._handleMouseMove.bind(this);
this._sock = new Websock();
this._sock.on('message', () => {
this._handle_message();
});
this._sock.on('open', () => {
if ((this._rfb_connection_state === 'connecting') &&
(this._rfb_init_state === '')) {
this._rfb_init_state = 'ProtocolVersion';
Log.Debug("Starting VNC handshake");
} else {
this._fail("Unexpected server connection while " +
this._rfb_connection_state);
}
});
this._sock.on('close', (e) => {
Log.Debug("WebSocket on-close event");
let msg = "";
if (e.code) {
msg = "(code: " + e.code;
if (e.reason) {
msg += ", reason: " + e.reason;
}
msg += ")";
}
switch (this._rfb_connection_state) {
case 'connecting':
this._fail("Connection closed " + msg);
break;
case 'connected':
// Handle disconnects that were initiated server-side
this._updateConnectionState('disconnecting');
this._updateConnectionState('disconnected');
break;
case 'disconnecting':
// Normal disconnection path
this._updateConnectionState('disconnected');
break;
case 'disconnected':
this._fail("Unexpected server disconnect " +
"when already disconnected " + msg);
break;
default:
this._fail("Unexpected server disconnect before connecting " +
msg);
break;
}
this._sock.off('close');
});
this._sock.on('error', e => Log.Warn("WebSocket on-error event"));
// Slight delay of the actual connection so that the caller has
// time to set up callbacks
setTimeout(this._updateConnectionState.bind(this, 'connecting'));
Log.Debug("<< RFB.constructor");
// ===== PROPERTIES =====
this.dragViewport = false;
this.focusOnClick = true;
this._viewOnly = false;
this._clipViewport = false;
this._scaleViewport = false;
this._resizeSession = false;
}
// ===== PROPERTIES =====
get viewOnly() { return this._viewOnly; }
set viewOnly(viewOnly) {
this._viewOnly = viewOnly;
if (this._rfb_connection_state === "connecting" ||
this._rfb_connection_state === "connected") {
if (viewOnly) {
this._keyboard.ungrab();
this._mouse.ungrab();
} else {
this._keyboard.grab();
this._mouse.grab();
}
}
}
get capabilities() { return this._capabilities; }
get touchButton() { return this._mouse.touchButton; }
set touchButton(button) { this._mouse.touchButton = button; }
get clipViewport() { return this._clipViewport; }
set clipViewport(viewport) {
this._clipViewport = viewport;
this._updateClip();
}
get scaleViewport() { return this._scaleViewport; }
set scaleViewport(scale) {
this._scaleViewport = scale;
// Scaling trumps clipping, so we may need to adjust
// clipping when enabling or disabling scaling
if (scale && this._clipViewport) {
this._updateClip();
}
this._updateScale();
if (!scale && this._clipViewport) {
this._updateClip();
}
}
get resizeSession() { return this._resizeSession; }
set resizeSession(resize) {
this._resizeSession = resize;
if (resize) {
this._requestRemoteResize();
}
}
get showDotCursor() { return this._showDotCursor; }
set showDotCursor(show) {
this._showDotCursor = show;
this._refreshCursor();
}
get background() { return this._screen.style.background; }
set background(cssValue) { this._screen.style.background = cssValue; }
// ===== PUBLIC METHODS =====
disconnect() {
this._updateConnectionState('disconnecting');
this._sock.off('error');
this._sock.off('message');
this._sock.off('open');
}
sendCredentials(creds) {
this._rfb_credentials = creds;
setTimeout(this._init_msg.bind(this), 0);
}
sendCtrlAltDel() {
if (this._rfb_connection_state !== 'connected' || this._viewOnly) { return; }
Log.Info("Sending Ctrl-Alt-Del");
this.sendKey(KeyTable.XK_Control_L, "ControlLeft", true);
this.sendKey(KeyTable.XK_Alt_L, "AltLeft", true);
this.sendKey(KeyTable.XK_Delete, "Delete", true);
this.sendKey(KeyTable.XK_Delete, "Delete", false);
this.sendKey(KeyTable.XK_Alt_L, "AltLeft", false);
this.sendKey(KeyTable.XK_Control_L, "ControlLeft", false);
}
machineShutdown() {
this._xvpOp(1, 2);
}
machineReboot() {
this._xvpOp(1, 3);
}
machineReset() {
this._xvpOp(1, 4);
}
// Send a key press. If 'down' is not specified then send a down key
// followed by an up key.
sendKey(keysym, code, down) {
if (this._rfb_connection_state !== 'connected' || this._viewOnly) { return; }
if (down === undefined) {
this.sendKey(keysym, code, true);
this.sendKey(keysym, code, false);
return;
}
const scancode = XtScancode[code];
if (this._qemuExtKeyEventSupported && scancode) {
// 0 is NoSymbol
keysym = keysym || 0;
Log.Info("Sending key (" + (down ? "down" : "up") + "): keysym " + keysym + ", scancode " + scancode);
RFB.messages.QEMUExtendedKeyEvent(this._sock, keysym, down, scancode);
} else {
if (!keysym) {
return;
}
Log.Info("Sending keysym (" + (down ? "down" : "up") + "): " + keysym);
RFB.messages.keyEvent(this._sock, keysym, down ? 1 : 0);
}
}
focus() {
this._canvas.focus();
}
blur() {
this._canvas.blur();
}
clipboardPasteFrom(text) {
if (this._rfb_connection_state !== 'connected' || this._viewOnly) { return; }
RFB.messages.clientCutText(this._sock, text);
}
// ===== PRIVATE METHODS =====
_connect() {
Log.Debug(">> RFB.connect");
Log.Info("connecting to " + this._url);
try {
// WebSocket.onopen transitions to the RFB init states
this._sock.open(this._url, ['binary']);
} catch (e) {
if (e.name === 'SyntaxError') {
this._fail("Invalid host or port (" + e + ")");
} else {
this._fail("Error when opening socket (" + e + ")");
}
}
// Make our elements part of the page
this._target.appendChild(this._screen);
this._cursor.attach(this._canvas);
this._refreshCursor();
// Monitor size changes of the screen
// FIXME: Use ResizeObserver, or hidden overflow
window.addEventListener('resize', this._eventHandlers.windowResize);
// Always grab focus on some kind of click event
this._canvas.addEventListener("mousedown", this._eventHandlers.focusCanvas);
this._canvas.addEventListener("touchstart", this._eventHandlers.focusCanvas);
Log.Debug("<< RFB.connect");
}
_disconnect() {
Log.Debug(">> RFB.disconnect");
this._cursor.detach();
this._canvas.removeEventListener("mousedown", this._eventHandlers.focusCanvas);
this._canvas.removeEventListener("touchstart", this._eventHandlers.focusCanvas);
window.removeEventListener('resize', this._eventHandlers.windowResize);
this._keyboard.ungrab();
this._mouse.ungrab();
this._sock.close();
try {
this._target.removeChild(this._screen);
} catch (e) {
if (e.name === 'NotFoundError') {
// Some cases where the initial connection fails
// can disconnect before the _screen is created
} else {
throw e;
}
}
clearTimeout(this._resizeTimeout);
Log.Debug("<< RFB.disconnect");
}
_focusCanvas(event) {
// Respect earlier handlers' request to not do side-effects
if (event.defaultPrevented) {
return;
}
if (!this.focusOnClick) {
return;
}
this.focus();
}
_windowResize(event) {
// If the window resized then our screen element might have
// as well. Update the viewport dimensions.
window.requestAnimationFrame(() => {
this._updateClip();
this._updateScale();
});
if (this._resizeSession) {
// Request changing the resolution of the remote display to
// the size of the local browser viewport.
// In order to not send multiple requests before the browser-resize
// is finished we wait 0.5 seconds before sending the request.
clearTimeout(this._resizeTimeout);
this._resizeTimeout = setTimeout(this._requestRemoteResize.bind(this), 500);
}
}
// Update state of clipping in Display object, and make sure the
// configured viewport matches the current screen size
_updateClip() {
const cur_clip = this._display.clipViewport;
let new_clip = this._clipViewport;
if (this._scaleViewport) {
// Disable viewport clipping if we are scaling
new_clip = false;
}
if (cur_clip !== new_clip) {
this._display.clipViewport = new_clip;
}
if (new_clip) {
// When clipping is enabled, the screen is limited to
// the size of the container.
const size = this._screenSize();
this._display.viewportChangeSize(size.w, size.h);
this._fixScrollbars();
}
}
_updateScale() {
if (!this._scaleViewport) {
this._display.scale = 1.0;
} else {
const size = this._screenSize();
this._display.autoscale(size.w, size.h);
}
this._fixScrollbars();
}
// Requests a change of remote desktop size. This message is an extension
// and may only be sent if we have received an ExtendedDesktopSize message
_requestRemoteResize() {
clearTimeout(this._resizeTimeout);
this._resizeTimeout = null;
if (!this._resizeSession || this._viewOnly ||
!this._supportsSetDesktopSize) {
return;
}
const size = this._screenSize();
RFB.messages.setDesktopSize(this._sock,
Math.floor(size.w), Math.floor(size.h),
this._screen_id, this._screen_flags);
Log.Debug('Requested new desktop size: ' +
size.w + 'x' + size.h);
}
// Gets the the size of the available screen
_screenSize() {
let r = this._screen.getBoundingClientRect();
return { w: r.width, h: r.height };
}
_fixScrollbars() {
// This is a hack because Chrome screws up the calculation
// for when scrollbars are needed. So to fix it we temporarily
// toggle them off and on.
const orig = this._screen.style.overflow;
this._screen.style.overflow = 'hidden';
// Force Chrome to recalculate the layout by asking for
// an element's dimensions
this._screen.getBoundingClientRect();
this._screen.style.overflow = orig;
}
/*
* Connection states:
* connecting
* connected
* disconnecting
* disconnected - permanent state
*/
_updateConnectionState(state) {
const oldstate = this._rfb_connection_state;
if (state === oldstate) {
Log.Debug("Already in state '" + state + "', ignoring");
return;
}
// The 'disconnected' state is permanent for each RFB object
if (oldstate === 'disconnected') {
Log.Error("Tried changing state of a disconnected RFB object");
return;
}
// Ensure proper transitions before doing anything
switch (state) {
case 'connected':
if (oldstate !== 'connecting') {
Log.Error("Bad transition to connected state, " +
"previous connection state: " + oldstate);
return;
}
break;
case 'disconnected':
if (oldstate !== 'disconnecting') {
Log.Error("Bad transition to disconnected state, " +
"previous connection state: " + oldstate);
return;
}
break;
case 'connecting':
if (oldstate !== '') {
Log.Error("Bad transition to connecting state, " +
"previous connection state: " + oldstate);
return;
}
break;
case 'disconnecting':
if (oldstate !== 'connected' && oldstate !== 'connecting') {
Log.Error("Bad transition to disconnecting state, " +
"previous connection state: " + oldstate);
return;
}
break;
default:
Log.Error("Unknown connection state: " + state);
return;
}
// State change actions
this._rfb_connection_state = state;
Log.Debug("New state '" + state + "', was '" + oldstate + "'.");
if (this._disconnTimer && state !== 'disconnecting') {
Log.Debug("Clearing disconnect timer");
clearTimeout(this._disconnTimer);
this._disconnTimer = null;
// make sure we don't get a double event
this._sock.off('close');
}
switch (state) {
case 'connecting':
this._connect();
break;
case 'connected':
this.dispatchEvent(new CustomEvent("connect", { detail: {} }));
break;
case 'disconnecting':
this._disconnect();
this._disconnTimer = setTimeout(() => {
Log.Error("Disconnection timed out.");
this._updateConnectionState('disconnected');
}, DISCONNECT_TIMEOUT * 1000);
break;
case 'disconnected':
this.dispatchEvent(new CustomEvent(
"disconnect", { detail:
{ clean: this._rfb_clean_disconnect } }));
break;
}
}
/* Print errors and disconnect
*
* The parameter 'details' is used for information that
* should be logged but not sent to the user interface.
*/
_fail(details) {
switch (this._rfb_connection_state) {
case 'disconnecting':
Log.Error("Failed when disconnecting: " + details);
break;
case 'connected':
Log.Error("Failed while connected: " + details);
break;
case 'connecting':
Log.Error("Failed when connecting: " + details);
break;
default:
Log.Error("RFB failure: " + details);
break;
}
this._rfb_clean_disconnect = false; //This is sent to the UI
// Transition to disconnected without waiting for socket to close
this._updateConnectionState('disconnecting');
this._updateConnectionState('disconnected');
return false;
}
_setCapability(cap, val) {
this._capabilities[cap] = val;
this.dispatchEvent(new CustomEvent("capabilities",
{ detail: { capabilities: this._capabilities } }));
}
_handle_message() {
if (this._sock.rQlen === 0) {
Log.Warn("handle_message called on an empty receive queue");
return;
}
switch (this._rfb_connection_state) {
case 'disconnected':
Log.Error("Got data while disconnected");
break;
case 'connected':
while (true) {
if (this._flushing) {
break;
}
if (!this._normal_msg()) {
break;
}
if (this._sock.rQlen === 0) {
break;
}
}
break;
default:
this._init_msg();
break;
}
}
_handleKeyEvent(keysym, code, down) {
this.sendKey(keysym, code, down);
}
_handleMouseButton(x, y, down, bmask) {
if (down) {
this._mouse_buttonMask |= bmask;
} else {
this._mouse_buttonMask &= ~bmask;
}
if (this.dragViewport) {
if (down && !this._viewportDragging) {
this._viewportDragging = true;
this._viewportDragPos = {'x': x, 'y': y};
this._viewportHasMoved = false;
// Skip sending mouse events
return;
} else {
this._viewportDragging = false;
// If we actually performed a drag then we are done
// here and should not send any mouse events
if (this._viewportHasMoved) {
return;
}
// Otherwise we treat this as a mouse click event.
// Send the button down event here, as the button up
// event is sent at the end of this function.
RFB.messages.pointerEvent(this._sock,
this._display.absX(x),
this._display.absY(y),
bmask);
}
}
if (this._viewOnly) { return; } // View only, skip mouse events
if (this._rfb_connection_state !== 'connected') { return; }
RFB.messages.pointerEvent(this._sock, this._display.absX(x), this._display.absY(y), this._mouse_buttonMask);
}
_handleMouseMove(x, y) {
if (this._viewportDragging) {
const deltaX = this._viewportDragPos.x - x;
const deltaY = this._viewportDragPos.y - y;
if (this._viewportHasMoved || (Math.abs(deltaX) > dragThreshold ||
Math.abs(deltaY) > dragThreshold)) {
this._viewportHasMoved = true;
this._viewportDragPos = {'x': x, 'y': y};
this._display.viewportChangePos(deltaX, deltaY);
}
// Skip sending mouse events
return;
}
if (this._viewOnly) { return; } // View only, skip mouse events
if (this._rfb_connection_state !== 'connected') { return; }
RFB.messages.pointerEvent(this._sock, this._display.absX(x), this._display.absY(y), this._mouse_buttonMask);
}
// Message Handlers
_negotiate_protocol_version() {
if (this._sock.rQwait("version", 12)) {
return false;
}
const sversion = this._sock.rQshiftStr(12).substr(4, 7);
Log.Info("Server ProtocolVersion: " + sversion);
let is_repeater = 0;
switch (sversion) {
case "000.000": // UltraVNC repeater
is_repeater = 1;
break;
case "003.003":
case "003.006": // UltraVNC
case "003.889": // Apple Remote Desktop
this._rfb_version = 3.3;
break;
case "003.007":
this._rfb_version = 3.7;
break;
case "003.008":
case "004.000": // Intel AMT KVM
case "004.001": // RealVNC 4.6
case "005.000": // RealVNC 5.3
this._rfb_version = 3.8;
break;
default:
return this._fail("Invalid server version " + sversion);
}
if (is_repeater) {
let repeaterID = "ID:" + this._repeaterID;
while (repeaterID.length < 250) {
repeaterID += "\0";
}
this._sock.send_string(repeaterID);
return true;
}
if (this._rfb_version > this._rfb_max_version) {
this._rfb_version = this._rfb_max_version;
}
const cversion = "00" + parseInt(this._rfb_version, 10) +
".00" + ((this._rfb_version * 10) % 10);
this._sock.send_string("RFB " + cversion + "\n");
Log.Debug('Sent ProtocolVersion: ' + cversion);
this._rfb_init_state = 'Security';
}
_negotiate_security() {
// Polyfill since IE and PhantomJS doesn't have
// TypedArray.includes()
function includes(item, array) {
for (let i = 0; i < array.length; i++) {
if (array[i] === item) {
return true;
}
}
return false;
}
if (this._rfb_version >= 3.7) {
// Server sends supported list, client decides
const num_types = this._sock.rQshift8();
if (this._sock.rQwait("security type", num_types, 1)) { return false; }
if (num_types === 0) {
this._rfb_init_state = "SecurityReason";
this._security_context = "no security types";
this._security_status = 1;
return this._init_msg();
}
const types = this._sock.rQshiftBytes(num_types);
Log.Debug("Server security types: " + types);
// Look for each auth in preferred order
if (includes(1, types)) {
this._rfb_auth_scheme = 1; // None
} else if (includes(22, types)) {
this._rfb_auth_scheme = 22; // XVP
} else if (includes(16, types)) {
this._rfb_auth_scheme = 16; // Tight
} else if (includes(2, types)) {
this._rfb_auth_scheme = 2; // VNC Auth
} else {
return this._fail("Unsupported security types (types: " + types + ")");
}
this._sock.send([this._rfb_auth_scheme]);
} else {
// Server decides
if (this._sock.rQwait("security scheme", 4)) { return false; }
this._rfb_auth_scheme = this._sock.rQshift32();
if (this._rfb_auth_scheme == 0) {
this._rfb_init_state = "SecurityReason";
this._security_context = "authentication scheme";
this._security_status = 1;
return this._init_msg();
}
}
this._rfb_init_state = 'Authentication';
Log.Debug('Authenticating using scheme: ' + this._rfb_auth_scheme);
return this._init_msg(); // jump to authentication
}
_handle_security_reason() {
if (this._sock.rQwait("reason length", 4)) {
return false;
}
const strlen = this._sock.rQshift32();
let reason = "";
if (strlen > 0) {
if (this._sock.rQwait("reason", strlen, 4)) { return false; }
reason = this._sock.rQshiftStr(strlen);
}
if (reason !== "") {
this.dispatchEvent(new CustomEvent(
"securityfailure",
{ detail: { status: this._security_status,
reason: reason } }));
return this._fail("Security negotiation failed on " +
this._security_context +
" (reason: " + reason + ")");
} else {
this.dispatchEvent(new CustomEvent(
"securityfailure",
{ detail: { status: this._security_status } }));
return this._fail("Security negotiation failed on " +
this._security_context);
}
}
// authentication
_negotiate_xvp_auth() {
if (!this._rfb_credentials.username ||
!this._rfb_credentials.password ||
!this._rfb_credentials.target) {
this.dispatchEvent(new CustomEvent(
"credentialsrequired",
{ detail: { types: ["username", "password", "target"] } }));
return false;
}
const xvp_auth_str = String.fromCharCode(this._rfb_credentials.username.length) +
String.fromCharCode(this._rfb_credentials.target.length) +
this._rfb_credentials.username +
this._rfb_credentials.target;
this._sock.send_string(xvp_auth_str);
this._rfb_auth_scheme = 2;
return this._negotiate_authentication();
}
_negotiate_std_vnc_auth() {
if (this._sock.rQwait("auth challenge", 16)) { return false; }
if (!this._rfb_credentials.password) {
this.dispatchEvent(new CustomEvent(
"credentialsrequired",
{ detail: { types: ["password"] } }));
return false;
}
// TODO(directxman12): make genDES not require an Array
const challenge = Array.prototype.slice.call(this._sock.rQshiftBytes(16));
const response = RFB.genDES(this._rfb_credentials.password, challenge);
this._sock.send(response);
this._rfb_init_state = "SecurityResult";
return true;
}
_negotiate_tight_tunnels(numTunnels) {
const clientSupportedTunnelTypes = {
0: { vendor: 'TGHT', signature: 'NOTUNNEL' }
};
const serverSupportedTunnelTypes = {};
// receive tunnel capabilities
for (let i = 0; i < numTunnels; i++) {
const cap_code = this._sock.rQshift32();
const cap_vendor = this._sock.rQshiftStr(4);
const cap_signature = this._sock.rQshiftStr(8);
serverSupportedTunnelTypes[cap_code] = { vendor: cap_vendor, signature: cap_signature };
}
Log.Debug("Server Tight tunnel types: " + serverSupportedTunnelTypes);
// Siemens touch panels have a VNC server that supports NOTUNNEL,
// but forgets to advertise it. Try to detect such servers by
// looking for their custom tunnel type.
if (serverSupportedTunnelTypes[1] &&
(serverSupportedTunnelTypes[1].vendor === "SICR") &&
(serverSupportedTunnelTypes[1].signature === "SCHANNEL")) {
Log.Debug("Detected Siemens server. Assuming NOTUNNEL support.");
serverSupportedTunnelTypes[0] = { vendor: 'TGHT', signature: 'NOTUNNEL' };
}
// choose the notunnel type
if (serverSupportedTunnelTypes[0]) {
if (serverSupportedTunnelTypes[0].vendor != clientSupportedTunnelTypes[0].vendor ||
serverSupportedTunnelTypes[0].signature != clientSupportedTunnelTypes[0].signature) {
return this._fail("Client's tunnel type had the incorrect " +
"vendor or signature");
}
Log.Debug("Selected tunnel type: " + clientSupportedTunnelTypes[0]);
this._sock.send([0, 0, 0, 0]); // use NOTUNNEL
return false; // wait until we receive the sub auth count to continue
} else {
return this._fail("Server wanted tunnels, but doesn't support " +
"the notunnel type");
}
}
_negotiate_tight_auth() {
if (!this._rfb_tightvnc) { // first pass, do the tunnel negotiation
if (this._sock.rQwait("num tunnels", 4)) { return false; }
const numTunnels = this._sock.rQshift32();
if (numTunnels > 0 && this._sock.rQwait("tunnel capabilities", 16 * numTunnels, 4)) { return false; }
this._rfb_tightvnc = true;
if (numTunnels > 0) {
this._negotiate_tight_tunnels(numTunnels);
return false; // wait until we receive the sub auth to continue
}
}
// second pass, do the sub-auth negotiation
if (this._sock.rQwait("sub auth count", 4)) { return false; }
const subAuthCount = this._sock.rQshift32();
if (subAuthCount === 0) { // empty sub-auth list received means 'no auth' subtype selected
this._rfb_init_state = 'SecurityResult';
return true;
}
if (this._sock.rQwait("sub auth capabilities", 16 * subAuthCount, 4)) { return false; }
const clientSupportedTypes = {
'STDVNOAUTH__': 1,
'STDVVNCAUTH_': 2
};
const serverSupportedTypes = [];
for (let i = 0; i < subAuthCount; i++) {
this._sock.rQshift32(); // capNum
const capabilities = this._sock.rQshiftStr(12);
serverSupportedTypes.push(capabilities);
}
Log.Debug("Server Tight authentication types: " + serverSupportedTypes);
for (let authType in clientSupportedTypes) {
if (serverSupportedTypes.indexOf(authType) != -1) {
this._sock.send([0, 0, 0, clientSupportedTypes[authType]]);
Log.Debug("Selected authentication type: " + authType);
switch (authType) {
case 'STDVNOAUTH__': // no auth
this._rfb_init_state = 'SecurityResult';
return true;
case 'STDVVNCAUTH_': // VNC auth
this._rfb_auth_scheme = 2;
return this._init_msg();
default:
return this._fail("Unsupported tiny auth scheme " +
"(scheme: " + authType + ")");
}
}
}
return this._fail("No supported sub-auth types!");
}
_negotiate_authentication() {
switch (this._rfb_auth_scheme) {
case 1: // no auth
if (this._rfb_version >= 3.8) {
this._rfb_init_state = 'SecurityResult';
return true;
}
this._rfb_init_state = 'ClientInitialisation';
return this._init_msg();
case 22: // XVP auth
return this._negotiate_xvp_auth();
case 2: // VNC authentication
return this._negotiate_std_vnc_auth();
case 16: // TightVNC Security Type
return this._negotiate_tight_auth();
default:
return this._fail("Unsupported auth scheme (scheme: " +
this._rfb_auth_scheme + ")");
}
}
_handle_security_result() {
if (this._sock.rQwait('VNC auth response ', 4)) { return false; }
const status = this._sock.rQshift32();
if (status === 0) { // OK
this._rfb_init_state = 'ClientInitialisation';
Log.Debug('Authentication OK');
return this._init_msg();
} else {
if (this._rfb_version >= 3.8) {
this._rfb_init_state = "SecurityReason";
this._security_context = "security result";
this._security_status = status;
return this._init_msg();
} else {
this.dispatchEvent(new CustomEvent(
"securityfailure",
{ detail: { status: status } }));
return this._fail("Security handshake failed");
}
}
}
_negotiate_server_init() {
if (this._sock.rQwait("server initialization", 24)) { return false; }
/* Screen size */
const width = this._sock.rQshift16();
const height = this._sock.rQshift16();
/* PIXEL_FORMAT */
const bpp = this._sock.rQshift8();
const depth = this._sock.rQshift8();
const big_endian = this._sock.rQshift8();
const true_color = this._sock.rQshift8();
const red_max = this._sock.rQshift16();
const green_max = this._sock.rQshift16();
const blue_max = this._sock.rQshift16();
const red_shift = this._sock.rQshift8();
const green_shift = this._sock.rQshift8();
const blue_shift = this._sock.rQshift8();
this._sock.rQskipBytes(3); // padding
// NB(directxman12): we don't want to call any callbacks or print messages until
// *after* we're past the point where we could backtrack
/* Connection name/title */
const name_length = this._sock.rQshift32();
if (this._sock.rQwait('server init name', name_length, 24)) { return false; }
this._fb_name = decodeUTF8(this._sock.rQshiftStr(name_length));
if (this._rfb_tightvnc) {
if (this._sock.rQwait('TightVNC extended server init header', 8, 24 + name_length)) { return false; }
// In TightVNC mode, ServerInit message is extended
const numServerMessages = this._sock.rQshift16();
const numClientMessages = this._sock.rQshift16();
const numEncodings = this._sock.rQshift16();
this._sock.rQskipBytes(2); // padding
const totalMessagesLength = (numServerMessages + numClientMessages + numEncodings) * 16;
if (this._sock.rQwait('TightVNC extended server init header', totalMessagesLength, 32 + name_length)) { return false; }
// we don't actually do anything with the capability information that TIGHT sends,
// so we just skip the all of this.
// TIGHT server message capabilities
this._sock.rQskipBytes(16 * numServerMessages);
// TIGHT client message capabilities
this._sock.rQskipBytes(16 * numClientMessages);
// TIGHT encoding capabilities
this._sock.rQskipBytes(16 * numEncodings);
}
// NB(directxman12): these are down here so that we don't run them multiple times
// if we backtrack
Log.Info("Screen: " + width + "x" + height +
", bpp: " + bpp + ", depth: " + depth +
", big_endian: " + big_endian +
", true_color: " + true_color +
", red_max: " + red_max +
", green_max: " + green_max +
", blue_max: " + blue_max +
", red_shift: " + red_shift +
", green_shift: " + green_shift +
", blue_shift: " + blue_shift);
if (big_endian !== 0) {
Log.Warn("Server native endian is not little endian");
}
if (red_shift !== 16) {
Log.Warn("Server native red-shift is not 16");
}
if (blue_shift !== 0) {
Log.Warn("Server native blue-shift is not 0");
}
// we're past the point where we could backtrack, so it's safe to call this
this.dispatchEvent(new CustomEvent(
"desktopname",
{ detail: { name: this._fb_name } }));
this._resize(width, height);
if (!this._viewOnly) { this._keyboard.grab(); }
if (!this._viewOnly) { this._mouse.grab(); }
this._fb_depth = 24;
if (this._fb_name === "Intel(r) AMT KVM") {
Log.Warn("Intel AMT KVM only supports 8/16 bit depths. Using low color mode.");
this._fb_depth = 8;
}
RFB.messages.pixelFormat(this._sock, this._fb_depth, true);
this._sendEncodings();
RFB.messages.fbUpdateRequest(this._sock, false, 0, 0, this._fb_width, this._fb_height);
this._updateConnectionState('connected');
return true;
}
_sendEncodings() {
const encs = [];
// In preference order
encs.push(encodings.encodingCopyRect);
// Only supported with full depth support
if (this._fb_depth == 24) {
encs.push(encodings.encodingTight);
encs.push(encodings.encodingTightPNG);
encs.push(encodings.encodingHextile);
encs.push(encodings.encodingRRE);
}
encs.push(encodings.encodingRaw);
// Psuedo-encoding settings
encs.push(encodings.pseudoEncodingQualityLevel0 + 6);
encs.push(encodings.pseudoEncodingCompressLevel0 + 2);
encs.push(encodings.pseudoEncodingDesktopSize);
encs.push(encodings.pseudoEncodingLastRect);
encs.push(encodings.pseudoEncodingQEMUExtendedKeyEvent);
encs.push(encodings.pseudoEncodingExtendedDesktopSize);
encs.push(encodings.pseudoEncodingXvp);
encs.push(encodings.pseudoEncodingFence);
encs.push(encodings.pseudoEncodingContinuousUpdates);
if (this._fb_depth == 24) {
encs.push(encodings.pseudoEncodingCursor);
}
RFB.messages.clientEncodings(this._sock, encs);
}
/* RFB protocol initialization states:
* ProtocolVersion
* Security
* Authentication
* SecurityResult
* ClientInitialization - not triggered by server message
* ServerInitialization
*/
_init_msg() {
switch (this._rfb_init_state) {
case 'ProtocolVersion':
return this._negotiate_protocol_version();
case 'Security':
return this._negotiate_security();
case 'Authentication':
return this._negotiate_authentication();
case 'SecurityResult':
return this._handle_security_result();
case 'SecurityReason':
return this._handle_security_reason();
case 'ClientInitialisation':
this._sock.send([this._shared ? 1 : 0]); // ClientInitialisation
this._rfb_init_state = 'ServerInitialisation';
return true;
case 'ServerInitialisation':
return this._negotiate_server_init();
default:
return this._fail("Unknown init state (state: " +
this._rfb_init_state + ")");
}
}
_handle_set_colour_map_msg() {
Log.Debug("SetColorMapEntries");
return this._fail("Unexpected SetColorMapEntries message");
}
_handle_server_cut_text() {
Log.Debug("ServerCutText");
if (this._sock.rQwait("ServerCutText header", 7, 1)) { return false; }
this._sock.rQskipBytes(3); // Padding
const length = this._sock.rQshift32();
if (this._sock.rQwait("ServerCutText", length, 8)) { return false; }
const text = this._sock.rQshiftStr(length);
if (this._viewOnly) { return true; }
this.dispatchEvent(new CustomEvent(
"clipboard",
{ detail: { text: text } }));
return true;
}
_handle_server_fence_msg() {
if (this._sock.rQwait("ServerFence header", 8, 1)) { return false; }
this._sock.rQskipBytes(3); // Padding
let flags = this._sock.rQshift32();
let length = this._sock.rQshift8();
if (this._sock.rQwait("ServerFence payload", length, 9)) { return false; }
if (length > 64) {
Log.Warn("Bad payload length (" + length + ") in fence response");
length = 64;
}
const payload = this._sock.rQshiftStr(length);
this._supportsFence = true;
/*
* Fence flags
*
* (1<<0) - BlockBefore
* (1<<1) - BlockAfter
* (1<<2) - SyncNext
* (1<<31) - Request
*/
if (!(flags & (1<<31))) {
return this._fail("Unexpected fence response");
}
// Filter out unsupported flags
// FIXME: support syncNext
flags &= (1<<0) | (1<<1);
// BlockBefore and BlockAfter are automatically handled by
// the fact that we process each incoming message
// synchronuosly.
RFB.messages.clientFence(this._sock, flags, payload);
return true;
}
_handle_xvp_msg() {
if (this._sock.rQwait("XVP version and message", 3, 1)) { return false; }
this._sock.rQskipBytes(1); // Padding
const xvp_ver = this._sock.rQshift8();
const xvp_msg = this._sock.rQshift8();
switch (xvp_msg) {
case 0: // XVP_FAIL
Log.Error("XVP Operation Failed");
break;
case 1: // XVP_INIT
this._rfb_xvp_ver = xvp_ver;
Log.Info("XVP extensions enabled (version " + this._rfb_xvp_ver + ")");
this._setCapability("power", true);
break;
default:
this._fail("Illegal server XVP message (msg: " + xvp_msg + ")");
break;
}
return true;
}
_normal_msg() {
let msg_type;
if (this._FBU.rects > 0) {
msg_type = 0;
} else {
msg_type = this._sock.rQshift8();
}
let first, ret;
switch (msg_type) {
case 0: // FramebufferUpdate
ret = this._framebufferUpdate();
if (ret && !this._enabledContinuousUpdates) {
RFB.messages.fbUpdateRequest(this._sock, true, 0, 0,
this._fb_width, this._fb_height);
}
return ret;
case 1: // SetColorMapEntries
return this._handle_set_colour_map_msg();
case 2: // Bell
Log.Debug("Bell");
this.dispatchEvent(new CustomEvent(
"bell",
{ detail: {} }));
return true;
case 3: // ServerCutText
return this._handle_server_cut_text();
case 150: // EndOfContinuousUpdates
first = !this._supportsContinuousUpdates;
this._supportsContinuousUpdates = true;
this._enabledContinuousUpdates = false;
if (first) {
this._enabledContinuousUpdates = true;
this._updateContinuousUpdates();
Log.Info("Enabling continuous updates.");
} else {
// FIXME: We need to send a framebufferupdaterequest here
// if we add support for turning off continuous updates
}
return true;
case 248: // ServerFence
return this._handle_server_fence_msg();
case 250: // XVP
return this._handle_xvp_msg();
default:
this._fail("Unexpected server message (type " + msg_type