core/rfb.js

   1 /*
   2  * noVNC: HTML5 VNC client
   3  * Copyright (C) 2012 Joel Martin
   4  * Copyright (C) 2016 Samuel Mannehed for Cendio AB
   5  * Licensed under MPL 2.0 (see LICENSE.txt)
   6  *
   7  * See README.md for usage and integration instructions.
   8  *
   9  * TIGHT decoder portion:
  10  * (c) 2012 Michael Tinglof, Joe Balaz, Les Piech (Mercuri.ca)
  11  */
  12
  13 import * as Log from './util/logging.js';
  14 import _ from './util/localization.js';
  15 import { decodeUTF8 } from './util/strings.js';
  16 import { browserSupportsCursorURIs } from './util/browsers.js';
  17 import Display from "./display.js";
  18 import Keyboard from "./input/keyboard.js";
  19 import Mouse from "./input/mouse.js";
  20 import Websock from "./websock.js";
  21 import Base64 from "./base64.js";
  22 import DES from "./des.js";
  23 import KeyTable from "./input/keysym.js";
  24 import XtScancode from "./input/xtscancodes.js";
  25 import Inflator from "./inflator.js";
  26 import { encodings, encodingName } from "./encodings.js";
  27
  28 /*jslint white: false, browser: true */
  29 /*global window, Util, Display, Keyboard, Mouse, Websock, Websock_native, Base64, DES, KeyTable, Inflator, XtScancode */
  30
  31 export default function RFB(target) {
  32     this._target = target;
  33
  34     // Connection details
  35     this._url = '';
  36     this._rfb_credentials = {};
  37
  38     // Internal state
  39     this._rfb_connection_state = '';
  40     this._rfb_init_state = '';
  41     this._rfb_auth_scheme = '';
  42     this._rfb_disconnect_reason = "";
  43
  44     // Server capabilities
  45     this._rfb_version = 0;
  46     this._rfb_max_version = 3.8;
  47     this._rfb_tightvnc = false;
  48     this._rfb_xvp_ver = 0;
  49
  50     this._fb_width = 0;
  51     this._fb_height = 0;
  52
  53     this._fb_name = "";
  54
  55     this._capabilities = { power: false, resize: false };
  56
  57     this._supportsFence = false;
  58
  59     this._supportsContinuousUpdates = false;
  60     this._enabledContinuousUpdates = false;
  61
  62     this._supportsSetDesktopSize = false;
  63     this._screen_id = 0;
  64     this._screen_flags = 0;
  65
  66     this._qemuExtKeyEventSupported = false;
  67
  68     // Internal objects
  69     this._sock = null;              // Websock object
  70     this._display = null;           // Display object
  71     this._flushing = false;         // Display flushing state
  72     this._keyboard = null;          // Keyboard input handler object
  73     this._mouse = null;             // Mouse input handler object
  74
  75     // Timers
  76     this._disconnTimer = null;      // disconnection timer
  77
  78     // Decoder states and stats
  79     this._encHandlers = {};
  80     this._encStats = {};
  81
  82     this._FBU = {
  83         rects: 0,
  84         subrects: 0,            // RRE and HEXTILE
  85         lines: 0,               // RAW
  86         tiles: 0,               // HEXTILE
  87         bytes: 0,
  88         x: 0,
  89         y: 0,
  90         width: 0,
  91         height: 0,
  92         encoding: 0,
  93         subencoding: -1,
  94         background: null,
  95         zlibs: []               // TIGHT zlib streams
  96     };
  97     for (var i = 0; i < 4; i++) {
  98         this._FBU.zlibs[i] = new Inflator();
  99     }
 100
 101     this._destBuff = null;
 102     this._paletteBuff = new Uint8Array(1024);  // 256 * 4 (max palette size * max bytes-per-pixel)
 103
 104     this._rre_chunk_sz = 100;
 105
 106     this._timing = {
 107         last_fbu: 0,
 108         fbu_total: 0,
 109         fbu_total_cnt: 0,
 110         full_fbu_total: 0,
 111         full_fbu_cnt: 0,
 112
 113         fbu_rt_start: 0,
 114         fbu_rt_total: 0,
 115         fbu_rt_cnt: 0,
 116         pixels: 0
 117     };
 118
 119     // Mouse state
 120     this._mouse_buttonMask = 0;
 121     this._mouse_arr = [];
 122     this._viewportDragging = false;
 123     this._viewportDragPos = {};
 124     this._viewportHasMoved = false;
 125
 126     // main setup
 127     Log.Debug(">> RFB.constructor");
 128
 129     // Target canvas must be able to have focus
 130     if (!this._target.hasAttribute('tabindex')) {
 131         this._target.tabIndex = -1;
 132     }
 133
 134     // populate encHandlers with bound versions
 135     this._encHandlers[encodings.encodingRaw] = RFB.encodingHandlers.RAW.bind(this);
 136     this._encHandlers[encodings.encodingCopyRect] = RFB.encodingHandlers.COPYRECT.bind(this);
 137     this._encHandlers[encodings.encodingRRE] = RFB.encodingHandlers.RRE.bind(this);
 138     this._encHandlers[encodings.encodingHextile] = RFB.encodingHandlers.HEXTILE.bind(this);
 139     this._encHandlers[encodings.encodingTight] = RFB.encodingHandlers.TIGHT.bind(this);
 140
 141     this._encHandlers[encodings.pseudoEncodingDesktopSize] = RFB.encodingHandlers.DesktopSize.bind(this);
 142     this._encHandlers[encodings.pseudoEncodingLastRect] = RFB.encodingHandlers.last_rect.bind(this);
 143     this._encHandlers[encodings.pseudoEncodingCursor] = RFB.encodingHandlers.Cursor.bind(this);
 144     this._encHandlers[encodings.pseudoEncodingQEMUExtendedKeyEvent] = RFB.encodingHandlers.QEMUExtendedKeyEvent.bind(this);
 145     this._encHandlers[encodings.pseudoEncodingExtendedDesktopSize] = RFB.encodingHandlers.ExtendedDesktopSize.bind(this);
 146
 147     // NB: nothing that needs explicit teardown should be done
 148     // before this point, since this can throw an exception
 149     try {
 150         this._display = new Display(this._target);
 151     } catch (exc) {
 152         Log.Error("Display exception: " + exc);
 153         throw exc;
 154     }
 155     this._display.onflush = this._onFlush.bind(this);
 156     this._display.clear();
 157
 158     this._keyboard = new Keyboard(this._target);
 159     this._keyboard.onkeyevent = this._handleKeyEvent.bind(this);
 160
 161     this._mouse = new Mouse(this._target);
 162     this._mouse.onmousebutton = this._handleMouseButton.bind(this);
 163     this._mouse.onmousemove = this._handleMouseMove.bind(this);
 164
 165     this._sock = new Websock();
 166     this._sock.on('message', this._handle_message.bind(this));
 167     this._sock.on('open', function () {
 168         if ((this._rfb_connection_state === 'connecting') &&
 169             (this._rfb_init_state === '')) {
 170             this._rfb_init_state = 'ProtocolVersion';
 171             Log.Debug("Starting VNC handshake");
 172         } else {
 173             this._fail("Unexpected server connection");
 174         }
 175     }.bind(this));
 176     this._sock.on('close', function (e) {
 177         Log.Warn("WebSocket on-close event");
 178         var msg = "";
 179         if (e.code) {
 180             msg = " (code: " + e.code;
 181             if (e.reason) {
 182                 msg += ", reason: " + e.reason;
 183             }
 184             msg += ")";
 185         }
 186         switch (this._rfb_connection_state) {
 187             case 'disconnecting':
 188                 this._updateConnectionState('disconnected');
 189                 break;
 190             case 'connecting':
 191                 this._fail('Failed to connect to server', msg);
 192                 break;
 193             case 'connected':
 194                 // Handle disconnects that were initiated server-side
 195                 this._updateConnectionState('disconnecting');
 196                 this._updateConnectionState('disconnected');
 197                 break;
 198             case 'disconnected':
 199                 this._fail("Unexpected server disconnect",
 200                            "Already disconnected: " + msg);
 201                 break;
 202             default:
 203                 this._fail("Unexpected server disconnect",
 204                            "Not in any state yet: " + msg);
 205                 break;
 206         }
 207         this._sock.off('close');
 208     }.bind(this));
 209     this._sock.on('error', function (e) {
 210         Log.Warn("WebSocket on-error event");
 211     });
 212
 213     Log.Debug("<< RFB.constructor");
 214 };
 215
 216 RFB.prototype = {
 217     // ===== PROPERTIES =====
 218
 219     disconnectTimeout: 3,
 220     viewportDrag: false,
 221
 222     _localCursor: false,
 223     get localCursor() { return this._localCursor; },
 224     set localCursor(cursor) {
 225         if (!cursor || (cursor in {'0': 1, 'no': 1, 'false': 1})) {
 226             this._localCursor = false;
 227             this._display.disableLocalCursor(); //Only show server-side cursor
 228         } else {
 229             if (browserSupportsCursorURIs()) {
 230                 this._localCursor = true;
 231             } else {
 232                 Log.Warn("Browser does not support local cursor");
 233                 this._display.disableLocalCursor();
 234             }
 235         }
 236
 237         // Need to send an updated list of encodings if we are connected
 238         if (this._rfb_connection_state === "connected") {
 239             this._sendEncodings();
 240         }
 241     },
 242
 243     _viewOnly: false,
 244     get viewOnly() { return this._viewOnly; },
 245     set viewOnly(viewOnly) {
 246         this._viewOnly = viewOnly;
 247
 248         if (this._rfb_connection_state === "connecting" ||
 249             this._rfb_connection_state === "connected") {
 250             if (viewOnly) {
 251                 this._keyboard.ungrab();
 252                 this._mouse.ungrab();
 253             } else {
 254                 this._keyboard.grab();
 255                 this._mouse.grab();
 256             }
 257         }
 258     },
 259
 260     get capabilities() { return this._capabilities; },
 261
 262     get touchButton() { return this._mouse.touchButton; },
 263     set touchButton(button) { this._mouse.touchButton = button; },
 264
 265     get scale() { return this._display.scale; },
 266     set scale(scale) { this._display.scale = scale; },
 267
 268     get viewport() { return this._display.viewport; },
 269     set viewport(viewport) { this._display.viewport = viewport; },
 270
 271     get isClipped() { return this._display.isClipped; },
 272
 273     // ===== EVENT HANDLERS =====
 274
 275     onupdatestate: function () {},  // onupdatestate(rfb, state, oldstate): connection state change
 276     onnotification: function () {}, // onnotification(rfb, msg, level, options): notification for the UI
 277     ondisconnected: function () {}, // ondisconnected(rfb, reason): disconnection finished
 278     oncredentialsrequired: function () {}, // oncredentialsrequired(rfb, types): VNC credentials are required
 279     onclipboard: function () {},    // onclipboard(rfb, text): RFB clipboard contents received
 280     onbell: function () {},         // onbell(rfb): RFB Bell message received
 281     onfbresize: function () {},     // onfbresize(rfb, width, height): frame buffer resized
 282     ondesktopname: function () {},  // ondesktopname(rfb, name): desktop name received
 283     oncapabilities: function () {}, // oncapabilities(rfb, caps): the supported capabilities has changed
 284
 285     // ===== PUBLIC METHODS =====
 286
 287     connect: function (url, options) {
 288         if (!url) {
 289             this._fail(_("Must specify URL"));
 290             return;
 291         }
 292
 293         this._url = url;
 294
 295         options = options || {}
 296
 297         this._rfb_credentials = options.credentials || {};
 298         this._shared = 'shared' in options ? !!options.shared : true;
 299         this._repeaterID = options.repeaterID || '';
 300
 301         this._rfb_init_state = '';
 302         this._updateConnectionState('connecting');
 303     },
 304
 305     disconnect: function () {
 306         this._updateConnectionState('disconnecting');
 307         this._sock.off('error');
 308         this._sock.off('message');
 309         this._sock.off('open');
 310     },
 311
 312     sendCredentials: function (creds) {
 313         this._rfb_credentials = creds;
 314         setTimeout(this._init_msg.bind(this), 0);
 315     },
 316
 317     sendCtrlAltDel: function () {
 318         if (this._rfb_connection_state !== 'connected' || this._viewOnly) { return; }
 319         Log.Info("Sending Ctrl-Alt-Del");
 320
 321         this.sendKey(KeyTable.XK_Control_L, "ControlLeft", true);
 322         this.sendKey(KeyTable.XK_Alt_L, "AltLeft", true);
 323         this.sendKey(KeyTable.XK_Delete, "Delete", true);
 324         this.sendKey(KeyTable.XK_Delete, "Delete", false);
 325         this.sendKey(KeyTable.XK_Alt_L, "AltLeft", false);
 326         this.sendKey(KeyTable.XK_Control_L, "ControlLeft", false);
 327     },
 328
 329     machineShutdown: function () {
 330         this._xvpOp(1, 2);
 331     },
 332
 333     machineReboot: function () {
 334         this._xvpOp(1, 3);
 335     },
 336
 337     machineReset: function () {
 338         this._xvpOp(1, 4);
 339     },
 340
 341     // Send a key press. If 'down' is not specified then send a down key
 342     // followed by an up key.
 343     sendKey: function (keysym, code, down) {
 344         if (this._rfb_connection_state !== 'connected' || this._viewOnly) { return; }
 345
 346         if (down === undefined) {
 347             this.sendKey(keysym, code, true);
 348             this.sendKey(keysym, code, false);
 349             return;
 350         }
 351
 352         var scancode = XtScancode[code];
 353
 354         if (this._qemuExtKeyEventSupported && scancode) {
 355             // 0 is NoSymbol
 356             keysym = keysym || 0;
 357
 358             Log.Info("Sending key (" + (down ? "down" : "up") + "): keysym " + keysym + ", scancode " + scancode);
 359
 360             RFB.messages.QEMUExtendedKeyEvent(this._sock, keysym, down, scancode);
 361         } else {
 362             if (!keysym) {
 363                 return;
 364             }
 365             Log.Info("Sending keysym (" + (down ? "down" : "up") + "): " + keysym);
 366             RFB.messages.keyEvent(this._sock, keysym, down ? 1 : 0);
 367         }
 368     },
 369
 370     clipboardPasteFrom: function (text) {
 371         if (this._rfb_connection_state !== 'connected' || this._viewOnly) { return; }
 372         RFB.messages.clientCutText(this._sock, text);
 373     },
 374
 375     autoscale: function (width, height, downscaleOnly) {
 376         if (this._rfb_connection_state !== 'connected') { return; }
 377         this._display.autoscale(width, height, downscaleOnly);
 378     },
 379
 380     viewportChangeSize: function(width, height) {
 381         if (this._rfb_connection_state !== 'connected') { return; }
 382         this._display.viewportChangeSize(width, height);
 383     },
 384
 385     // Requests a change of remote desktop size. This message is an extension
 386     // and may only be sent if we have received an ExtendedDesktopSize message
 387     requestDesktopSize: function (width, height) {
 388         if (this._rfb_connection_state !== 'connected' ||
 389             this._viewOnly) {
 390             return;
 391         }
 392
 393         if (!this._supportsSetDesktopSize) {
 394             return;
 395         }
 396
 397         RFB.messages.setDesktopSize(this._sock, width, height,
 398                                     this._screen_id, this._screen_flags);
 399     },
 400
 401
 402     // ===== PRIVATE METHODS =====
 403
 404     _connect: function () {
 405         Log.Debug(">> RFB.connect");
 406
 407         Log.Info("connecting to " + this._url);
 408
 409         try {
 410             // WebSocket.onopen transitions to the RFB init states
 411             this._sock.open(this._url, ['binary']);
 412         } catch (e) {
 413             if (e.name === 'SyntaxError') {
 414                 this._fail("Invalid host or port value given", e);
 415             } else {
 416                 this._fail("Error while connecting", e);
 417             }
 418         }
 419
 420         // Always grab focus on some kind of click event
 421         this._target.addEventListener("mousedown", this._focusCanvas);
 422         this._target.addEventListener("touchstart", this._focusCanvas);
 423
 424         Log.Debug("<< RFB.connect");
 425     },
 426
 427     _disconnect: function () {
 428         Log.Debug(">> RFB.disconnect");
 429         this._target.removeEventListener("mousedown", this._focusCanvas);
 430         this._target.removeEventListener("touchstart", this._focusCanvas);
 431         this._cleanup();
 432         this._sock.close();
 433         this._print_stats();
 434         Log.Debug("<< RFB.disconnect");
 435     },
 436
 437     _print_stats: function () {
 438         var stats = this._encStats;
 439
 440         Log.Info("Encoding stats for this connection:");
 441         Object.keys(stats).forEach(function (key) {
 442             var s = stats[key];
 443             if (s[0] + s[1] > 0) {
 444                 Log.Info("    " + encodingName(key) + ": " + s[0] + " rects");
 445             }
 446         });
 447
 448         Log.Info("Encoding stats since page load:");
 449         Object.keys(stats).forEach(function (key) {
 450             var s = stats[key];
 451             Log.Info("    " + encodingName(key) + ": " + s[1] + " rects");
 452         });
 453     },
 454
 455     _cleanup: function () {
 456         if (!this._viewOnly) { this._keyboard.ungrab(); }
 457         if (!this._viewOnly) { this._mouse.ungrab(); }
 458         this._display.defaultCursor();
 459         if (Log.get_logging() !== 'debug') {
 460             // Show noVNC logo when disconnected, unless in
 461             // debug mode
 462             this._display.clear();
 463         }
 464     },
 465
 466     // Event handler for canvas so this points to the canvas element
 467     _focusCanvas: function(event) {
 468         // Respect earlier handlers' request to not do side-effects
 469         if (!event.defaultPrevented)
 470             this.focus();
 471     },
 472
 473     /*
 474      * Connection states:
 475      *   connecting
 476      *   connected
 477      *   disconnecting
 478      *   disconnected - permanent state
 479      */
 480     _updateConnectionState: function (state) {
 481         var oldstate = this._rfb_connection_state;
 482
 483         if (state === oldstate) {
 484             Log.Debug("Already in state '" + state + "', ignoring");
 485             return;
 486         }
 487
 488         // The 'disconnected' state is permanent for each RFB object
 489         if (oldstate === 'disconnected') {
 490             Log.Error("Tried changing state of a disconnected RFB object");
 491             return;
 492         }
 493
 494         // Ensure proper transitions before doing anything
 495         switch (state) {
 496             case 'connected':
 497                 if (oldstate !== 'connecting') {
 498                     Log.Error("Bad transition to connected state, " +
 499                                "previous connection state: " + oldstate);
 500                     return;
 501                 }
 502                 break;
 503
 504             case 'disconnected':
 505                 if (oldstate !== 'disconnecting') {
 506                     Log.Error("Bad transition to disconnected state, " +
 507                                "previous connection state: " + oldstate);
 508                     return;
 509                 }
 510                 break;
 511
 512             case 'connecting':
 513                 if (oldstate !== '') {
 514                     Log.Error("Bad transition to connecting state, " +
 515                                "previous connection state: " + oldstate);
 516                     return;
 517                 }
 518                 break;
 519
 520             case 'disconnecting':
 521                 if (oldstate !== 'connected' && oldstate !== 'connecting') {
 522                     Log.Error("Bad transition to disconnecting state, " +
 523                                "previous connection state: " + oldstate);
 524                     return;
 525                 }
 526                 break;
 527
 528             default:
 529                 Log.Error("Unknown connection state: " + state);
 530                 return;
 531         }
 532
 533         // State change actions
 534
 535         this._rfb_connection_state = state;
 536         this.onupdatestate(this, state, oldstate);
 537
 538         var smsg = "New state '" + state + "', was '" + oldstate + "'.";
 539         Log.Debug(smsg);
 540
 541         if (this._disconnTimer && state !== 'disconnecting') {
 542             Log.Debug("Clearing disconnect timer");
 543             clearTimeout(this._disconnTimer);
 544             this._disconnTimer = null;
 545
 546             // make sure we don't get a double event
 547             this._sock.off('close');
 548         }
 549
 550         switch (state) {
 551             case 'disconnected':
 552                 // Call ondisconnected callback after onupdatestate since
 553                 // we don't know if the UI only displays the latest message
 554                 if (this._rfb_disconnect_reason !== "") {
 555                     this.ondisconnected(this, this._rfb_disconnect_reason);
 556                 } else {
 557                     // No reason means clean disconnect
 558                     this.ondisconnected(this);
 559                 }
 560                 break;
 561
 562             case 'connecting':
 563                 this._connect();
 564                 break;
 565
 566             case 'disconnecting':
 567                 this._disconnect();
 568
 569                 this._disconnTimer = setTimeout(function () {
 570                     this._rfb_disconnect_reason = _("Disconnect timeout");
 571                     this._updateConnectionState('disconnected');
 572                 }.bind(this), this._disconnectTimeout * 1000);
 573                 break;
 574         }
 575     },
 576
 577     /* Print errors and disconnect
 578      *
 579      * The optional parameter 'details' is used for information that
 580      * should be logged but not sent to the user interface.
 581      */
 582     _fail: function (msg, details) {
 583         var fullmsg = msg;
 584         if (typeof details !== 'undefined') {
 585             fullmsg = msg + " (" + details + ")";
 586         }
 587         switch (this._rfb_connection_state) {
 588             case 'disconnecting':
 589                 Log.Error("Failed when disconnecting: " + fullmsg);
 590                 break;
 591             case 'connected':
 592                 Log.Error("Failed while connected: " + fullmsg);
 593                 break;
 594             case 'connecting':
 595                 Log.Error("Failed when connecting: " + fullmsg);
 596                 break;
 597             default:
 598                 Log.Error("RFB failure: " + fullmsg);
 599                 break;
 600         }
 601         this._rfb_disconnect_reason = msg; //This is sent to the UI
 602
 603         // Transition to disconnected without waiting for socket to close
 604         this._updateConnectionState('disconnecting');
 605         this._updateConnectionState('disconnected');
 606
 607         return false;
 608     },
 609
 610     /*
 611      * Send a notification to the UI. Valid levels are:
 612      *   'normal'|'warn'|'error'
 613      *
 614      *   NOTE: Options could be added in the future.
 615      *   NOTE: If this function is called multiple times, remember that the
 616      *         interface could be only showing the latest notification.
 617      */
 618     _notification: function(msg, level, options) {
 619         switch (level) {
 620             case 'normal':
 621             case 'warn':
 622             case 'error':
 623                 Log.Debug("Notification[" + level + "]:" + msg);
 624                 break;
 625             default:
 626                 Log.Error("Invalid notification level: " + level);
 627                 return;
 628         }
 629
 630         if (options) {
 631             this.onnotification(this, msg, level, options);
 632         } else {
 633             this.onnotification(this, msg, level);
 634         }
 635     },
 636
 637     _setCapability: function (cap, val) {
 638         this._capabilities[cap] = val;
 639         this.oncapabilities(this, this._capabilities);
 640     },
 641
 642     _handle_message: function () {
 643         if (this._sock.rQlen() === 0) {
 644             Log.Warn("handle_message called on an empty receive queue");
 645             return;
 646         }
 647
 648         switch (this._rfb_connection_state) {
 649             case 'disconnected':
 650                 Log.Error("Got data while disconnected");
 651                 break;
 652             case 'connected':
 653                 while (true) {
 654                     if (this._flushing) {
 655                         break;
 656                     }
 657                     if (!this._normal_msg()) {
 658                         break;
 659                     }
 660                     if (this._sock.rQlen() === 0) {
 661                         break;
 662                     }
 663                 }
 664                 break;
 665             default:
 666                 this._init_msg();
 667                 break;
 668         }
 669     },
 670
 671     _handleKeyEvent: function (keysym, code, down) {
 672         this.sendKey(keysym, code, down);
 673     },
 674
 675     _handleMouseButton: function (x, y, down, bmask) {
 676         if (down) {
 677             this._mouse_buttonMask |= bmask;
 678         } else {
 679             this._mouse_buttonMask &= ~bmask;
 680         }
 681
 682         if (this._viewportDrag) {
 683             if (down && !this._viewportDragging) {
 684                 this._viewportDragging = true;
 685                 this._viewportDragPos = {'x': x, 'y': y};
 686
 687                 // Skip sending mouse events
 688                 return;
 689             } else {
 690                 this._viewportDragging = false;
 691
 692                 // If the viewport didn't actually move, then treat as a mouse click event
 693                 // Send the button down event here, as the button up event is sent at the end of this function
 694                 if (!this._viewportHasMoved && !this._viewOnly) {
 695                     RFB.messages.pointerEvent(this._sock, this._display.absX(x), this._display.absY(y), bmask);
 696                 }
 697                 this._viewportHasMoved = false;
 698             }
 699         }
 700
 701         if (this._viewOnly) { return; } // View only, skip mouse events
 702
 703         if (this._rfb_connection_state !== 'connected') { return; }
 704         RFB.messages.pointerEvent(this._sock, this._display.absX(x), this._display.absY(y), this._mouse_buttonMask);
 705     },
 706
 707     _handleMouseMove: function (x, y) {
 708         if (this._viewportDragging) {
 709             var deltaX = this._viewportDragPos.x - x;
 710             var deltaY = this._viewportDragPos.y - y;
 711
 712             // The goal is to trigger on a certain physical width, the
 713             // devicePixelRatio brings us a bit closer but is not optimal.
 714             var dragThreshold = 10 * (window.devicePixelRatio || 1);
 715
 716             if (this._viewportHasMoved || (Math.abs(deltaX) > dragThreshold ||
 717                                            Math.abs(deltaY) > dragThreshold)) {
 718                 this._viewportHasMoved = true;
 719
 720                 this._viewportDragPos = {'x': x, 'y': y};
 721                 this._display.viewportChangePos(deltaX, deltaY);
 722             }
 723
 724             // Skip sending mouse events
 725             return;
 726         }
 727
 728         if (this._viewOnly) { return; } // View only, skip mouse events
 729
 730         if (this._rfb_connection_state !== 'connected') { return; }
 731         RFB.messages.pointerEvent(this._sock, this._display.absX(x), this._display.absY(y), this._mouse_buttonMask);
 732     },
 733
 734     // Message Handlers
 735
 736     _negotiate_protocol_version: function () {
 737         if (this._sock.rQlen() < 12) {
 738             return this._fail("Error while negotiating with server",
 739                               "Incomplete protocol version");
 740         }
 741
 742         var sversion = this._sock.rQshiftStr(12).substr(4, 7);
 743         Log.Info("Server ProtocolVersion: " + sversion);
 744         var is_repeater = 0;
 745         switch (sversion) {
 746             case "000.000":  // UltraVNC repeater
 747                 is_repeater = 1;
 748                 break;
 749             case "003.003":
 750             case "003.006":  // UltraVNC
 751             case "003.889":  // Apple Remote Desktop
 752                 this._rfb_version = 3.3;
 753                 break;
 754             case "003.007":
 755                 this._rfb_version = 3.7;
 756                 break;
 757             case "003.008":
 758             case "004.000":  // Intel AMT KVM
 759             case "004.001":  // RealVNC 4.6
 760             case "005.000":  // RealVNC 5.3
 761                 this._rfb_version = 3.8;
 762                 break;
 763             default:
 764                 return this._fail("Unsupported server",
 765                                   "Invalid server version: " + sversion);
 766         }
 767
 768         if (is_repeater) {
 769             var repeaterID = "ID:" + this._repeaterID;
 770             while (repeaterID.length < 250) {
 771                 repeaterID += "\0";
 772             }
 773             this._sock.send_string(repeaterID);
 774             return true;
 775         }
 776
 777         if (this._rfb_version > this._rfb_max_version) {
 778             this._rfb_version = this._rfb_max_version;
 779         }
 780
 781         var cversion = "00" + parseInt(this._rfb_version, 10) +
 782                        ".00" + ((this._rfb_version * 10) % 10);
 783         this._sock.send_string("RFB " + cversion + "\n");
 784         Log.Debug('Sent ProtocolVersion: ' + cversion);
 785
 786         this._rfb_init_state = 'Security';
 787     },
 788
 789     _negotiate_security: function () {
 790         // Polyfill since IE and PhantomJS doesn't have
 791         // TypedArray.includes()
 792         function includes(item, array) {
 793             for (var i = 0; i < array.length; i++) {
 794                 if (array[i] === item) {
 795                     return true;
 796                 }
 797             }
 798             return false;
 799         }
 800
 801         if (this._rfb_version >= 3.7) {
 802             // Server sends supported list, client decides
 803             var num_types = this._sock.rQshift8();
 804             if (this._sock.rQwait("security type", num_types, 1)) { return false; }
 805
 806             if (num_types === 0) {
 807                 var strlen = this._sock.rQshift32();
 808                 var reason = this._sock.rQshiftStr(strlen);
 809                 return this._fail("Error while negotiating with server",
 810                                   "Security failure: " + reason);
 811             }
 812
 813             var types = this._sock.rQshiftBytes(num_types);
 814             Log.Debug("Server security types: " + types);
 815
 816             // Look for each auth in preferred order
 817             this._rfb_auth_scheme = 0;
 818             if (includes(1, types)) {
 819                 this._rfb_auth_scheme = 1; // None
 820             } else if (includes(22, types)) {
 821                 this._rfb_auth_scheme = 22; // XVP
 822             } else if (includes(16, types)) {
 823                 this._rfb_auth_scheme = 16; // Tight
 824             } else if (includes(2, types)) {
 825                 this._rfb_auth_scheme = 2; // VNC Auth
 826             } else {
 827                 return this._fail("Unsupported server",
 828                                   "Unsupported security types: " + types);
 829             }
 830
 831             this._sock.send([this._rfb_auth_scheme]);
 832         } else {
 833             // Server decides
 834             if (this._sock.rQwait("security scheme", 4)) { return false; }
 835             this._rfb_auth_scheme = this._sock.rQshift32();
 836         }
 837
 838         this._rfb_init_state = 'Authentication';
 839         Log.Debug('Authenticating using scheme: ' + this._rfb_auth_scheme);
 840
 841         return this._init_msg(); // jump to authentication
 842     },
 843
 844     // authentication
 845     _negotiate_xvp_auth: function () {
 846         if (!this._rfb_credentials.username ||
 847             !this._rfb_credentials.password ||
 848             !this._rfb_credentials.target) {
 849             this.oncredentialsrequired(this, ["username", "password", "target"]);
 850             return false;
 851         }
 852
 853         var xvp_auth_str = String.fromCharCode(this._rfb_credentials.username.length) +
 854                            String.fromCharCode(this._rfb_credentials.target.length) +
 855                            this._rfb_credentials.username +
 856                            this._rfb_credentials.target;
 857         this._sock.send_string(xvp_auth_str);
 858         this._rfb_auth_scheme = 2;
 859         return this._negotiate_authentication();
 860     },
 861
 862     _negotiate_std_vnc_auth: function () {
 863         if (this._sock.rQwait("auth challenge", 16)) { return false; }
 864
 865         if (!this._rfb_credentials.password) {
 866             this.oncredentialsrequired(this, ["password"]);
 867             return false;
 868         }
 869
 870         // TODO(directxman12): make genDES not require an Array
 871         var challenge = Array.prototype.slice.call(this._sock.rQshiftBytes(16));
 872         var response = RFB.genDES(this._rfb_credentials.password, challenge);
 873         this._sock.send(response);
 874         this._rfb_init_state = "SecurityResult";
 875         return true;
 876     },
 877
 878     _negotiate_tight_tunnels: function (numTunnels) {
 879         var clientSupportedTunnelTypes = {
 880             0: { vendor: 'TGHT', signature: 'NOTUNNEL' }
 881         };
 882         var serverSupportedTunnelTypes = {};
 883         // receive tunnel capabilities
 884         for (var i = 0; i < numTunnels; i++) {
 885             var cap_code = this._sock.rQshift32();
 886             var cap_vendor = this._sock.rQshiftStr(4);
 887             var cap_signature = this._sock.rQshiftStr(8);
 888             serverSupportedTunnelTypes[cap_code] = { vendor: cap_vendor, signature: cap_signature };
 889         }
 890
 891         // choose the notunnel type
 892         if (serverSupportedTunnelTypes[0]) {
 893             if (serverSupportedTunnelTypes[0].vendor != clientSupportedTunnelTypes[0].vendor ||
 894                 serverSupportedTunnelTypes[0].signature != clientSupportedTunnelTypes[0].signature) {
 895                 return this._fail("Unsupported server",
 896                                   "Client's tunnel type had the incorrect " +
 897                                   "vendor or signature");
 898             }
 899             this._sock.send([0, 0, 0, 0]);  // use NOTUNNEL
 900             return false; // wait until we receive the sub auth count to continue
 901         } else {
 902             return this._fail("Unsupported server",
 903                               "Server wanted tunnels, but doesn't support " +
 904                               "the notunnel type");
 905         }
 906     },
 907
 908     _negotiate_tight_auth: function () {
 909         if (!this._rfb_tightvnc) {  // first pass, do the tunnel negotiation
 910             if (this._sock.rQwait("num tunnels", 4)) { return false; }
 911             var numTunnels = this._sock.rQshift32();
 912             if (numTunnels > 0 && this._sock.rQwait("tunnel capabilities", 16 * numTunnels, 4)) { return false; }
 913
 914             this._rfb_tightvnc = true;
 915
 916             if (numTunnels > 0) {
 917                 this._negotiate_tight_tunnels(numTunnels);
 918                 return false;  // wait until we receive the sub auth to continue
 919             }
 920         }
 921
 922         // second pass, do the sub-auth negotiation
 923         if (this._sock.rQwait("sub auth count", 4)) { return false; }
 924         var subAuthCount = this._sock.rQshift32();
 925         if (subAuthCount === 0) {  // empty sub-auth list received means 'no auth' subtype selected
 926             this._rfb_init_state = 'SecurityResult';
 927             return true;
 928         }
 929
 930         if (this._sock.rQwait("sub auth capabilities", 16 * subAuthCount, 4)) { return false; }
 931
 932         var clientSupportedTypes = {
 933             'STDVNOAUTH__': 1,
 934             'STDVVNCAUTH_': 2
 935         };
 936
 937         var serverSupportedTypes = [];
 938
 939         for (var i = 0; i < subAuthCount; i++) {
 940             var capNum = this._sock.rQshift32();
 941             var capabilities = this._sock.rQshiftStr(12);
 942             serverSupportedTypes.push(capabilities);
 943         }
 944
 945         for (var authType in clientSupportedTypes) {
 946             if (serverSupportedTypes.indexOf(authType) != -1) {
 947                 this._sock.send([0, 0, 0, clientSupportedTypes[authType]]);
 948
 949                 switch (authType) {
 950                     case 'STDVNOAUTH__':  // no auth
 951                         this._rfb_init_state = 'SecurityResult';
 952                         return true;
 953                     case 'STDVVNCAUTH_': // VNC auth
 954                         this._rfb_auth_scheme = 2;
 955                         return this._init_msg();
 956                     default:
 957                         return this._fail("Unsupported server",
 958                                           "Unsupported tiny auth scheme: " +
 959                                           authType);
 960                 }
 961             }
 962         }
 963
 964         return this._fail("Unsupported server",
 965                           "No supported sub-auth types!");
 966     },
 967
 968     _negotiate_authentication: function () {
 969         switch (this._rfb_auth_scheme) {
 970             case 0:  // connection failed
 971                 if (this._sock.rQwait("auth reason", 4)) { return false; }
 972                 var strlen = this._sock.rQshift32();
 973                 var reason = this._sock.rQshiftStr(strlen);
 974                 return this._fail("Authentication failure", reason);
 975
 976             case 1:  // no auth
 977                 if (this._rfb_version >= 3.8) {
 978                     this._rfb_init_state = 'SecurityResult';
 979                     return true;
 980                 }
 981                 this._rfb_init_state = 'ClientInitialisation';
 982                 return this._init_msg();
 983
 984             case 22:  // XVP auth
 985                 return this._negotiate_xvp_auth();
 986
 987             case 2:  // VNC authentication
 988                 return this._negotiate_std_vnc_auth();
 989
 990             case 16:  // TightVNC Security Type
 991                 return this._negotiate_tight_auth();
 992
 993             default:
 994                 return this._fail("Unsupported server",
 995                                   "Unsupported auth scheme: " +
 996                                   this._rfb_auth_scheme);
 997         }
 998     },
 999
1000     _handle_security_result: function () {
1001         if (this._sock.rQwait('VNC auth response ', 4)) { return false; }
1002         switch (this._sock.rQshift32()) {
1003             case 0:  // OK
1004                 this._rfb_init_state = 'ClientInitialisation';
1005                 Log.Debug('Authentication OK');
1006                 return this._init_msg();
1007             case 1:  // failed
1008                 if (this._rfb_version >= 3.8) {
1009                     var length = this._sock.rQshift32();
1010                     if (this._sock.rQwait("SecurityResult reason", length, 8)) { return false; }
1011                     var reason = this._sock.rQshiftStr(length);
1012                     return this._fail("Authentication failure", reason);
1013                 } else {
1014                     return this._fail("Authentication failure");
1015                 }
1016             case 2:
1017                 return this._fail("Too many authentication attempts");
1018             default:
1019                 return this._fail("Unsupported server",
1020                                   "Unknown SecurityResult");
1021         }
1022     },
1023
1024     _negotiate_server_init: function () {
1025         if (this._sock.rQwait("server initialization", 24)) { return false; }
1026
1027         /* Screen size */
1028         var width = this._sock.rQshift16();
1029         var height = this._sock.rQshift16();
1030
1031         /* PIXEL_FORMAT */
1032         var bpp         = this._sock.rQshift8();
1033         var depth       = this._sock.rQshift8();
1034         var big_endian  = this._sock.rQshift8();
1035         var true_color  = this._sock.rQshift8();
1036
1037         var red_max     = this._sock.rQshift16();
1038         var green_max   = this._sock.rQshift16();
1039         var blue_max    = this._sock.rQshift16();
1040         var red_shift   = this._sock.rQshift8();
1041         var green_shift = this._sock.rQshift8();
1042         var blue_shift  = this._sock.rQshift8();
1043         this._sock.rQskipBytes(3);  // padding
1044
1045         // NB(directxman12): we don't want to call any callbacks or print messages until
1046         //                   *after* we're past the point where we could backtrack
1047
1048         /* Connection name/title */
1049         var name_length = this._sock.rQshift32();
1050         if (this._sock.rQwait('server init name', name_length, 24)) { return false; }
1051         this._fb_name = decodeUTF8(this._sock.rQshiftStr(name_length));
1052
1053         if (this._rfb_tightvnc) {
1054             if (this._sock.rQwait('TightVNC extended server init header', 8, 24 + name_length)) { return false; }
1055             // In TightVNC mode, ServerInit message is extended
1056             var numServerMessages = this._sock.rQshift16();
1057             var numClientMessages = this._sock.rQshift16();
1058             var numEncodings = this._sock.rQshift16();
1059             this._sock.rQskipBytes(2);  // padding
1060
1061             var totalMessagesLength = (numServerMessages + numClientMessages + numEncodings) * 16;
1062             if (this._sock.rQwait('TightVNC extended server init header', totalMessagesLength, 32 + name_length)) { return false; }
1063
1064             // we don't actually do anything with the capability information that TIGHT sends,
1065             // so we just skip the all of this.
1066
1067             // TIGHT server message capabilities
1068             this._sock.rQskipBytes(16 * numServerMessages);
1069
1070             // TIGHT client message capabilities
1071             this._sock.rQskipBytes(16 * numClientMessages);
1072
1073             // TIGHT encoding capabilities
1074             this._sock.rQskipBytes(16 * numEncodings);
1075         }
1076
1077         // NB(directxman12): these are down here so that we don't run them multiple times
1078         //                   if we backtrack
1079         Log.Info("Screen: " + width + "x" + height +
1080                   ", bpp: " + bpp + ", depth: " + depth +
1081                   ", big_endian: " + big_endian +
1082                   ", true_color: " + true_color +
1083                   ", red_max: " + red_max +
1084                   ", green_max: " + green_max +
1085                   ", blue_max: " + blue_max +
1086                   ", red_shift: " + red_shift +
1087                   ", green_shift: " + green_shift +
1088                   ", blue_shift: " + blue_shift);
1089
1090         if (big_endian !== 0) {
1091             Log.Warn("Server native endian is not little endian");
1092         }
1093
1094         if (red_shift !== 16) {
1095             Log.Warn("Server native red-shift is not 16");
1096         }
1097
1098         if (blue_shift !== 0) {
1099             Log.Warn("Server native blue-shift is not 0");
1100         }
1101
1102         // we're past the point where we could backtrack, so it's safe to call this
1103         this.ondesktopname(this, this._fb_name);
1104
1105         this._resize(width, height);
1106
1107         if (!this._viewOnly) { this._keyboard.grab(); }
1108         if (!this._viewOnly) { this._mouse.grab(); }
1109
1110         this._fb_depth = 24;
1111
1112         if (this._fb_name === "Intel(r) AMT KVM") {
1113             Log.Warn("Intel AMT KVM only supports 8/16 bit depths. Using low color mode.");
1114             this._fb_depth = 8;
1115         }
1116
1117         RFB.messages.pixelFormat(this._sock, this._fb_depth, true);
1118         this._sendEncodings();
1119         RFB.messages.fbUpdateRequest(this._sock, false, 0, 0, this._fb_width, this._fb_height);
1120
1121         this._timing.fbu_rt_start = (new Date()).getTime();
1122         this._timing.pixels = 0;
1123
1124         // Cursor will be server side until the server decides to honor
1125         // our request and send over the cursor image
1126         this._display.disableLocalCursor();
1127
1128         this._updateConnectionState('connected');
1129         return true;
1130     },
1131
1132     _sendEncodings: function () {
1133         var encs = [];
1134
1135         // In preference order
1136         encs.push(encodings.encodingCopyRect);
1137         // Only supported with full depth support
1138         if (this._fb_depth == 24) {
1139             encs.push(encodings.encodingTight);
1140             encs.push(encodings.encodingHextile);
1141             encs.push(encodings.encodingRRE);
1142         }
1143         encs.push(encodings.encodingRaw);
1144
1145         // Psuedo-encoding settings
1146         encs.push(encodings.pseudoEncodingTightPNG);
1147         encs.push(encodings.pseudoEncodingQualityLevel0 + 6);
1148         encs.push(encodings.pseudoEncodingCompressLevel0 + 2);
1149
1150         encs.push(encodings.pseudoEncodingDesktopSize);
1151         encs.push(encodings.pseudoEncodingLastRect);
1152         encs.push(encodings.pseudoEncodingQEMUExtendedKeyEvent);
1153         encs.push(encodings.pseudoEncodingExtendedDesktopSize);
1154         encs.push(encodings.pseudoEncodingXvp);
1155         encs.push(encodings.pseudoEncodingFence);
1156         encs.push(encodings.pseudoEncodingContinuousUpdates);
1157
1158         if (this._localCursor && this._fb_depth == 24) {
1159             encs.push(encodings.pseudoEncodingCursor);
1160         }
1161
1162         RFB.messages.clientEncodings(this._sock, encs);
1163     },
1164
1165     /* RFB protocol initialization states:
1166      *   ProtocolVersion
1167      *   Security
1168      *   Authentication
1169      *   SecurityResult
1170      *   ClientInitialization - not triggered by server message
1171      *   ServerInitialization
1172      */
1173     _init_msg: function () {
1174         switch (this._rfb_init_state) {
1175             case 'ProtocolVersion':
1176                 return this._negotiate_protocol_version();
1177
1178             case 'Security':
1179                 return this._negotiate_security();
1180
1181             case 'Authentication':
1182                 return this._negotiate_authentication();
1183
1184             case 'SecurityResult':
1185                 return this._handle_security_result();
1186
1187             case 'ClientInitialisation':
1188                 this._sock.send([this._shared ? 1 : 0]); // ClientInitialisation
1189                 this._rfb_init_state = 'ServerInitialisation';
1190                 return true;
1191
1192             case 'ServerInitialisation':
1193                 return this._negotiate_server_init();
1194
1195             default:
1196                 return this._fail("Internal error", "Unknown init state: " +
1197                                   this._rfb_init_state);
1198         }
1199     },
1200
1201     _handle_set_colour_map_msg: function () {
1202         Log.Debug("SetColorMapEntries");
1203
1204         return this._fail("Protocol error", "Unexpected SetColorMapEntries message");
1205     },
1206
1207     _handle_server_cut_text: function () {
1208         Log.Debug("ServerCutText");
1209
1210         if (this._sock.rQwait("ServerCutText header", 7, 1)) { return false; }
1211         this._sock.rQskipBytes(3);  // Padding
1212         var length = this._sock.rQshift32();
1213         if (this._sock.rQwait("ServerCutText", length, 8)) { return false; }
1214
1215         var text = this._sock.rQshiftStr(length);
1216
1217         if (this._viewOnly) { return true; }
1218
1219         this.onclipboard(this, text);
1220
1221         return true;
1222     },
1223
1224     _handle_server_fence_msg: function() {
1225         if (this._sock.rQwait("ServerFence header", 8, 1)) { return false; }
1226         this._sock.rQskipBytes(3); // Padding
1227         var flags = this._sock.rQshift32();
1228         var length = this._sock.rQshift8();
1229
1230         if (this._sock.rQwait("ServerFence payload", length, 9)) { return false; }
1231
1232         if (length > 64) {
1233             Log.Warn("Bad payload length (" + length + ") in fence response");
1234             length = 64;
1235         }
1236
1237         var payload = this._sock.rQshiftStr(length);
1238
1239         this._supportsFence = true;
1240
1241         /*
1242          * Fence flags
1243          *
1244          *  (1<<0)  - BlockBefore
1245          *  (1<<1)  - BlockAfter
1246          *  (1<<2)  - SyncNext
1247          *  (1<<31) - Request
1248          */
1249
1250         if (!(flags & (1<<31))) {
1251             return this._fail("Internal error",
1252                               "Unexpected fence response");
1253         }
1254
1255         // Filter out unsupported flags
1256         // FIXME: support syncNext
1257         flags &= (1<<0) | (1<<1);
1258
1259         // BlockBefore and BlockAfter are automatically handled by
1260         // the fact that we process each incoming message
1261         // synchronuosly.
1262         RFB.messages.clientFence(this._sock, flags, payload);
1263
1264         return true;
1265     },
1266
1267     _handle_xvp_msg: function () {
1268         if (this._sock.rQwait("XVP version and message", 3, 1)) { return false; }
1269         this._sock.rQskip8();  // Padding
1270         var xvp_ver = this._sock.rQshift8();
1271         var xvp_msg = this._sock.rQshift8();
1272
1273         switch (xvp_msg) {
1274             case 0:  // XVP_FAIL
1275                 Log.Error("Operation Failed");
1276                 this._notification("XVP Operation Failed", 'error');
1277                 break;
1278             case 1:  // XVP_INIT
1279                 this._rfb_xvp_ver = xvp_ver;
1280                 Log.Info("XVP extensions enabled (version " + this._rfb_xvp_ver + ")");
1281                 this._setCapability("power", true);
1282                 break;
1283             default:
1284                 this._fail("Unexpected server message",
1285                            "Illegal server XVP message " + xvp_msg);
1286                 break;
1287         }
1288
1289         return true;
1290     },
1291
1292     _normal_msg: function () {
1293         var msg_type;
1294
1295         if (this._FBU.rects > 0) {
1296             msg_type = 0;
1297         } else {
1298             msg_type = this._sock.rQshift8();
1299         }
1300
1301         switch (msg_type) {
1302             case 0:  // FramebufferUpdate
1303                 var ret = this._framebufferUpdate();
1304                 if (ret && !this._enabledContinuousUpdates) {
1305                     RFB.messages.fbUpdateRequest(this._sock, true, 0, 0,
1306                                                  this._fb_width, this._fb_height);
1307                 }
1308                 return ret;
1309
1310             case 1:  // SetColorMapEntries
1311                 return this._handle_set_colour_map_msg();
1312
1313             case 2:  // Bell
1314                 Log.Debug("Bell");
1315                 this.onbell(this);
1316                 return true;
1317
1318             case 3:  // ServerCutText
1319                 return this._handle_server_cut_text();
1320
1321             case 150: // EndOfContinuousUpdates
1322                 var first = !(this._supportsContinuousUpdates);
1323                 this._supportsContinuousUpdates = true;
1324                 this._enabledContinuousUpdates = false;
1325                 if (first) {
1326                     this._enabledContinuousUpdates = true;
1327                     this._updateContinuousUpdates();
1328                     Log.Info("Enabling continuous updates.");
1329                 } else {
1330                     // FIXME: We need to send a framebufferupdaterequest here
1331                     // if we add support for turning off continuous updates
1332                 }
1333                 return true;
1334
1335             case 248: // ServerFence
1336                 return this._handle_server_fence_msg();
1337
1338             case 250:  // XVP
1339                 return this._handle_xvp_msg();
1340
1341             default:
1342                 this._fail("Unexpected server message", "Type:" + msg_type);
1343                 Log.Debug("sock.rQslice(0, 30): " + this._sock.rQslice(0, 30));
1344                 return true;
1345         }
1346     },
1347
1348     _onFlush: function() {
1349         this._flushing = false;
1350         // Resume processing
1351         if (this._sock.rQlen() > 0) {
1352             this._handle_message();
1353         }
1354     },
1355
1356     _framebufferUpdate: function () {
1357         var ret = true;
1358         var now;
1359
1360         if (this._FBU.rects === 0) {
1361             if (this._sock.rQwait("FBU header", 3, 1)) { return false; }
1362             this._sock.rQskip8();  // Padding
1363             this._FBU.rects = this._sock.rQshift16();
1364             this._FBU.bytes = 0;
1365             this._timing.cur_fbu = 0;
1366             if (this._timing.fbu_rt_start > 0) {
1367                 now = (new Date()).getTime();
1368                 Log.Info("First FBU latency: " + (now - this._timing.fbu_rt_start));
1369             }
1370
1371             // Make sure the previous frame is fully rendered first
1372             // to avoid building up an excessive queue
1373             if (this._display.pending()) {
1374                 this._flushing = true;
1375                 this._display.flush();
1376                 return false;
1377             }
1378         }
1379
1380         while (this._FBU.rects > 0) {
1381             if (this._rfb_connection_state !== 'connected') { return false; }
1382
1383             if (this._sock.rQwait("FBU", this._FBU.bytes)) { return false; }
1384             if (this._FBU.bytes === 0) {
1385                 if (this._sock.rQwait("rect header", 12)) { return false; }
1386                 /* New FramebufferUpdate */
1387
1388                 var hdr = this._sock.rQshiftBytes(12);
1389                 this._FBU.x        = (hdr[0] << 8) + hdr[1];
1390                 this._FBU.y        = (hdr[2] << 8) + hdr[3];
1391                 this._FBU.width    = (hdr[4] << 8) + hdr[5];
1392                 this._FBU.height   = (hdr[6] << 8) + hdr[7];
1393                 this._FBU.encoding = parseInt((hdr[8] << 24) + (hdr[9] << 16) +
1394                                               (hdr[10] << 8) + hdr[11], 10);
1395
1396                 if (!this._encHandlers[this._FBU.encoding]) {
1397                     this._fail("Unexpected server message",
1398                                "Unsupported encoding " +
1399                                this._FBU.encoding);
1400                     return false;
1401                 }
1402             }
1403
1404             this._timing.last_fbu = (new Date()).getTime();
1405
1406             ret = this._encHandlers[this._FBU.encoding]();
1407
1408             now = (new Date()).getTime();
1409             this._timing.cur_fbu += (now - this._timing.last_fbu);
1410
1411             if (ret) {
1412                 if (!(this._FBU.encoding in this._encStats)) {
1413                     this._encStats[this._FBU.encoding] = [0, 0];
1414                 }
1415                 this._encStats[this._FBU.encoding][0]++;
1416                 this._encStats[this._FBU.encoding][1]++;
1417                 this._timing.pixels += this._FBU.width * this._FBU.height;
1418             }
1419
1420             if (this._timing.pixels >= (this._fb_width * this._fb_height)) {
1421                 if ((this._FBU.width === this._fb_width && this._FBU.height === this._fb_height) ||
1422                     this._timing.fbu_rt_start > 0) {
1423                     this._timing.full_fbu_total += this._timing.cur_fbu;
1424                     this._timing.full_fbu_cnt++;
1425                     Log.Info("Timing of full FBU, curr: " +
1426                               this._timing.cur_fbu + ", total: " +
1427                               this._timing.full_fbu_total + ", cnt: " +
1428                               this._timing.full_fbu_cnt + ", avg: " +
1429                               (this._timing.full_fbu_total / this._timing.full_fbu_cnt));
1430                 }
1431
1432                 if (this._timing.fbu_rt_start > 0) {
1433                     var fbu_rt_diff = now - this._timing.fbu_rt_start;
1434                     this._timing.fbu_rt_total += fbu_rt_diff;
1435                     this._timing.fbu_rt_cnt++;
1436                     Log.Info("full FBU round-trip, cur: " +
1437                               fbu_rt_diff + ", total: " +
1438                               this._timing.fbu_rt_total + ", cnt: " +
1439                               this._timing.fbu_rt_cnt + ", avg: " +
1440                               (this._timing.fbu_rt_total / this._timing.fbu_rt_cnt));
1441                     this._timing.fbu_rt_start = 0;
1442                 }
1443             }
1444
1445             if (!ret) { return ret; }  // need more data
1446         }
1447
1448         this._display.flip();
1449
1450         return true;  // We finished this FBU
1451     },
1452
1453     _updateContinuousUpdates: function() {
1454         if (!this._enabledContinuousUpdates) { return; }
1455
1456         RFB.messages.enableContinuousUpdates(this._sock, true, 0, 0,
1457                                              this._fb_width, this._fb_height);
1458     },
1459
1460     _resize: function(width, height) {
1461         this._fb_width = width;
1462         this._fb_height = height;
1463
1464         this._destBuff = new Uint8Array(this._fb_width * this._fb_height * 4);
1465
1466         this._display.resize(this._fb_width, this._fb_height);
1467         this.onfbresize(this, this._fb_width, this._fb_height);
1468
1469         this._timing.fbu_rt_start = (new Date()).getTime();
1470         this._updateContinuousUpdates();
1471     },
1472
1473     _xvpOp: function (ver, op) {
1474         if (this._rfb_xvp_ver < ver) { return; }
1475         Log.Info("Sending XVP operation " + op + " (version " + ver + ")");
1476         RFB.messages.xvpOp(this._sock, ver, op);
1477     },
1478 };
1479
1480 // Class Methods
1481 RFB.messages = {
1482     keyEvent: function (sock, keysym, down) {
1483         var buff = sock._sQ;
1484         var offset = sock._sQlen;
1485
1486         buff[offset] = 4;  // msg-type
1487         buff[offset + 1] = down;
1488
1489         buff[offset + 2] = 0;
1490         buff[offset + 3] = 0;
1491
1492         buff[offset + 4] = (keysym >> 24);
1493         buff[offset + 5] = (keysym >> 16);
1494         buff[offset + 6] = (keysym >> 8);
1495         buff[offset + 7] = keysym;
1496
1497         sock._sQlen += 8;
1498         sock.flush();
1499     },
1500
1501     QEMUExtendedKeyEvent: function (sock, keysym, down, keycode) {
1502         function getRFBkeycode(xt_scancode) {
1503             var upperByte = (keycode >> 8);
1504             var lowerByte = (keycode & 0x00ff);
1505             if (upperByte === 0xe0 && lowerByte < 0x7f) {
1506                 lowerByte = lowerByte | 0x80;
1507                 return lowerByte;
1508             }
1509             return xt_scancode;
1510         }
1511
1512         var buff = sock._sQ;
1513         var offset = sock._sQlen;
1514
1515         buff[offset] = 255; // msg-type
1516         buff[offset + 1] = 0; // sub msg-type
1517
1518         buff[offset + 2] = (down >> 8);
1519         buff[offset + 3] = down;
1520
1521         buff[offset + 4] = (keysym >> 24);
1522         buff[offset + 5] = (keysym >> 16);
1523         buff[offset + 6] = (keysym >> 8);
1524         buff[offset + 7] = keysym;
1525
1526         var RFBkeycode = getRFBkeycode(keycode);
1527
1528         buff[offset + 8] = (RFBkeycode >> 24);
1529         buff[offset + 9] = (RFBkeycode >> 16);
1530         buff[offset + 10] = (RFBkeycode >> 8);
1531         buff[offset + 11] = RFBkeycode;
1532
1533         sock._sQlen += 12;
1534         sock.flush();
1535     },
1536
1537     pointerEvent: function (sock, x, y, mask) {
1538         var buff = sock._sQ;
1539         var offset = sock._sQlen;
1540
1541         buff[offset] = 5; // msg-type
1542
1543         buff[offset + 1] = mask;
1544
1545         buff[offset + 2] = x >> 8;
1546         buff[offset + 3] = x;
1547
1548         buff[offset + 4] = y >> 8;
1549         buff[offset + 5] = y;
1550
1551         sock._sQlen += 6;
1552         sock.flush();
1553     },
1554
1555     // TODO(directxman12): make this unicode compatible?
1556     clientCutText: function (sock, text) {
1557         var buff = sock._sQ;
1558         var offset = sock._sQlen;
1559
1560         buff[offset] = 6; // msg-type
1561
1562         buff[offset + 1] = 0; // padding
1563         buff[offset + 2] = 0; // padding
1564         buff[offset + 3] = 0; // padding
1565
1566         var n = text.length;
1567
1568         buff[offset + 4] = n >> 24;
1569         buff[offset + 5] = n >> 16;
1570         buff[offset + 6] = n >> 8;
1571         buff[offset + 7] = n;
1572
1573         for (var i = 0; i < n; i++) {
1574             buff[offset + 8 + i] =  text.charCodeAt(i);
1575         }
1576
1577         sock._sQlen += 8 + n;
1578         sock.flush();
1579     },
1580
1581     setDesktopSize: function (sock, width, height, id, flags) {
1582         var buff = sock._sQ;
1583         var offset = sock._sQlen;
1584
1585         buff[offset] = 251;              // msg-type
1586         buff[offset + 1] = 0;            // padding
1587         buff[offset + 2] = width >> 8;   // width
1588         buff[offset + 3] = width;
1589         buff[offset + 4] = height >> 8;  // height
1590         buff[offset + 5] = height;
1591
1592         buff[offset + 6] = 1;            // number-of-screens
1593         buff[offset + 7] = 0;            // padding
1594
1595         // screen array
1596         buff[offset + 8] = id >> 24;     // id
1597         buff[offset + 9] = id >> 16;
1598         buff[offset + 10] = id >> 8;
1599         buff[offset + 11] = id;
1600         buff[offset + 12] = 0;           // x-position
1601         buff[offset + 13] = 0;
1602         buff[offset + 14] = 0;           // y-position
1603         buff[offset + 15] = 0;
1604         buff[offset + 16] = width >> 8;  // width
1605         buff[offset + 17] = width;
1606         buff[offset + 18] = height >> 8; // height
1607         buff[offset + 19] = height;
1608         buff[offset + 20] = flags >> 24; // flags
1609         buff[offset + 21] = flags >> 16;
1610         buff[offset + 22] = flags >> 8;
1611         buff[offset + 23] = flags;
1612
1613         sock._sQlen += 24;
1614         sock.flush();
1615     },
1616
1617     clientFence: function (sock, flags, payload) {
1618         var buff = sock._sQ;
1619         var offset = sock._sQlen;
1620
1621         buff[offset] = 248; // msg-type
1622
1623         buff[offset + 1] = 0; // padding
1624         buff[offset + 2] = 0; // padding
1625         buff[offset + 3] = 0; // padding
1626
1627         buff[offset + 4] = flags >> 24; // flags
1628         buff[offset + 5] = flags >> 16;
1629         buff[offset + 6] = flags >> 8;
1630         buff[offset + 7] = flags;
1631
1632         var n = payload.length;
1633
1634         buff[offset + 8] = n; // length
1635
1636         for (var i = 0; i < n; i++) {
1637             buff[offset + 9 + i] = payload.charCodeAt(i);
1638         }
1639
1640         sock._sQlen += 9 + n;
1641         sock.flush();
1642     },
1643
1644     enableContinuousUpdates: function (sock, enable, x, y, width, height) {
1645         var buff = sock._sQ;
1646         var offset = sock._sQlen;
1647
1648         buff[offset] = 150;             // msg-type
1649         buff[offset + 1] = enable;      // enable-flag
1650
1651         buff[offset + 2] = x >> 8;      // x
1652         buff[offset + 3] = x;
1653         buff[offset + 4] = y >> 8;      // y
1654         buff[offset + 5] = y;
1655         buff[offset + 6] = width >> 8;  // width
1656         buff[offset + 7] = width;
1657         buff[offset + 8] = height >> 8; // height
1658         buff[offset + 9] = height;
1659
1660         sock._sQlen += 10;
1661         sock.flush();
1662     },
1663
1664     pixelFormat: function (sock, depth, true_color) {
1665         var buff = sock._sQ;
1666         var offset = sock._sQlen;
1667
1668         var bpp, bits;
1669
1670         if (depth > 16) {
1671             bpp = 32;
1672         } else if (depth > 8) {
1673             bpp = 16;
1674         } else {
1675             bpp = 8;
1676         }
1677
1678         bits = Math.floor(depth/3);
1679
1680         buff[offset] = 0;  // msg-type
1681
1682         buff[offset + 1] = 0; // padding
1683         buff[offset + 2] = 0; // padding
1684         buff[offset + 3] = 0; // padding
1685
1686         buff[offset + 4] = bpp;                 // bits-per-pixel
1687         buff[offset + 5] = depth;               // depth
1688         buff[offset + 6] = 0;                   // little-endian
1689         buff[offset + 7] = true_color ? 1 : 0;  // true-color
1690
1691         buff[offset + 8] = 0;    // red-max
1692         buff[offset + 9] = (1 << bits) - 1;  // red-max
1693
1694         buff[offset + 10] = 0;   // green-max
1695         buff[offset + 11] = (1 << bits) - 1; // green-max
1696
1697         buff[offset + 12] = 0;   // blue-max
1698         buff[offset + 13] = (1 << bits) - 1; // blue-max
1699
1700         buff[offset + 14] = bits * 2; // red-shift
1701         buff[offset + 15] = bits * 1; // green-shift
1702         buff[offset + 16] = bits * 0; // blue-shift
1703
1704         buff[offset + 17] = 0;   // padding
1705         buff[offset + 18] = 0;   // padding
1706         buff[offset + 19] = 0;   // padding
1707
1708         sock._sQlen += 20;
1709         sock.flush();
1710     },
1711
1712     clientEncodings: function (sock, encodings) {
1713         var buff = sock._sQ;
1714         var offset = sock._sQlen;
1715
1716         buff[offset] = 2; // msg-type
1717         buff[offset + 1] = 0; // padding
1718
1719         buff[offset + 2] = encodings.length >> 8;
1720         buff[offset + 3] = encodings.length;
1721
1722         var i, j = offset + 4;
1723         for (i = 0; i < encodings.length; i++) {
1724             var enc = encodings[i];
1725             buff[j] = enc >> 24;
1726             buff[j + 1] = enc >> 16;
1727             buff[j + 2] = enc >> 8;
1728             buff[j + 3] = enc;
1729
1730             j += 4;
1731         }
1732
1733         sock._sQlen += j - offset;
1734         sock.flush();
1735     },
1736
1737     fbUpdateRequest: function (sock, incremental, x, y, w, h) {
1738         var buff = sock._sQ;
1739         var offset = sock._sQlen;
1740
1741         if (typeof(x) === "undefined") { x = 0; }
1742         if (typeof(y) === "undefined") { y = 0; }
1743
1744         buff[offset] = 3;  // msg-type
1745         buff[offset + 1] = incremental ? 1 : 0;
1746
1747         buff[offset + 2] = (x >> 8) & 0xFF;
1748         buff[offset + 3] = x & 0xFF;
1749
1750         buff[offset + 4] = (y >> 8) & 0xFF;
1751         buff[offset + 5] = y & 0xFF;
1752
1753         buff[offset + 6] = (w >> 8) & 0xFF;
1754         buff[offset + 7] = w & 0xFF;
1755
1756         buff[offset + 8] = (h >> 8) & 0xFF;
1757         buff[offset + 9] = h & 0xFF;
1758
1759         sock._sQlen += 10;
1760         sock.flush();
1761     },
1762
1763     xvpOp: function (sock, ver, op) {
1764         var buff = sock._sQ;
1765         var offset = sock._sQlen;
1766
1767         buff[offset] = 250; // msg-type
1768         buff[offset + 1] = 0; // padding
1769
1770         buff[offset + 2] = ver;
1771         buff[offset + 3] = op;
1772
1773         sock._sQlen += 4;
1774         sock.flush();
1775     },
1776 };
1777
1778 RFB.genDES = function (password, challenge) {
1779     var passwd = [];
1780     for (var i = 0; i < password.length; i++) {
1781         passwd.push(password.charCodeAt(i));
1782     }
1783     return (new DES(passwd)).encrypt(challenge);
1784 };
1785
1786 RFB.encodingHandlers = {
1787     RAW: function () {
1788         if (this._FBU.lines === 0) {
1789             this._FBU.lines = this._FBU.height;
1790         }
1791
1792         var pixelSize = this._fb_depth == 8 ? 1 : 4;
1793         this._FBU.bytes = this._FBU.width * pixelSize;  // at least a line
1794         if (this._sock.rQwait("RAW", this._FBU.bytes)) { return false; }
1795         var cur_y = this._FBU.y + (this._FBU.height - this._FBU.lines);
1796         var curr_height = Math.min(this._FBU.lines,
1797                                    Math.floor(this._sock.rQlen() / (this._FBU.width * pixelSize)));
1798         var data = this._sock.get_rQ();
1799         var index = this._sock.get_rQi();
1800         if (this._fb_depth == 8) {
1801             var pixels = this._FBU.width * curr_height
1802             var newdata = new Uint8Array(pixels * 4);
1803             var i;
1804             for (i = 0;i < pixels;i++) {
1805                 newdata[i * 4 + 0] = ((data[index + i] >> 0) & 0x3) * 255 / 3;
1806                 newdata[i * 4 + 1] = ((data[index + i] >> 2) & 0x3) * 255 / 3;
1807                 newdata[i * 4 + 2] = ((data[index + i] >> 4) & 0x3) * 255 / 3;
1808                 newdata[i * 4 + 4] = 0;
1809             }
1810             data = newdata;
1811             index = 0;
1812         }
1813         this._display.blitImage(this._FBU.x, cur_y, this._FBU.width,
1814                                 curr_height, data, index);
1815         this._sock.rQskipBytes(this._FBU.width * curr_height * pixelSize);
1816         this._FBU.lines -= curr_height;
1817
1818         if (this._FBU.lines > 0) {
1819             this._FBU.bytes = this._FBU.width * pixelSize;  // At least another line
1820         } else {
1821             this._FBU.rects--;
1822             this._FBU.bytes = 0;
1823         }
1824
1825         return true;
1826     },
1827
1828     COPYRECT: function () {
1829         this._FBU.bytes = 4;
1830         if (this._sock.rQwait("COPYRECT", 4)) { return false; }
1831         this._display.copyImage(this._sock.rQshift16(), this._sock.rQshift16(),
1832                                 this._FBU.x, this._FBU.y, this._FBU.width,
1833                                 this._FBU.height);
1834
1835         this._FBU.rects--;
1836         this._FBU.bytes = 0;
1837         return true;
1838     },
1839
1840     RRE: function () {
1841         var color;
1842         if (this._FBU.subrects === 0) {
1843             this._FBU.bytes = 4 + 4;
1844             if (this._sock.rQwait("RRE", 4 + 4)) { return false; }
1845             this._FBU.subrects = this._sock.rQshift32();
1846             color = this._sock.rQshiftBytes(4);  // Background
1847             this._display.fillRect(this._FBU.x, this._FBU.y, this._FBU.width, this._FBU.height, color);
1848         }
1849
1850         while (this._FBU.subrects > 0 && this._sock.rQlen() >= (4 + 8)) {
1851             color = this._sock.rQshiftBytes(4);
1852             var x = this._sock.rQshift16();
1853             var y = this._sock.rQshift16();
1854             var width = this._sock.rQshift16();
1855             var height = this._sock.rQshift16();
1856             this._display.fillRect(this._FBU.x + x, this._FBU.y + y, width, height, color);
1857             this._FBU.subrects--;
1858         }
1859
1860         if (this._FBU.subrects > 0) {
1861             var chunk = Math.min(this._rre_chunk_sz, this._FBU.subrects);
1862             this._FBU.bytes = (4 + 8) * chunk;
1863         } else {
1864             this._FBU.rects--;
1865             this._FBU.bytes = 0;
1866         }
1867
1868         return true;
1869     },
1870
1871     HEXTILE: function () {
1872         var rQ = this._sock.get_rQ();
1873         var rQi = this._sock.get_rQi();
1874
1875         if (this._FBU.tiles === 0) {
1876             this._FBU.tiles_x = Math.ceil(this._FBU.width / 16);
1877             this._FBU.tiles_y = Math.ceil(this._FBU.height / 16);
1878             this._FBU.total_tiles = this._FBU.tiles_x * this._FBU.tiles_y;
1879             this._FBU.tiles = this._FBU.total_tiles;
1880         }
1881
1882         while (this._FBU.tiles > 0) {
1883             this._FBU.bytes = 1;
1884             if (this._sock.rQwait("HEXTILE subencoding", this._FBU.bytes)) { return false; }
1885             var subencoding = rQ[rQi];  // Peek
1886             if (subencoding > 30) {  // Raw
1887                 this._fail("Unexpected server message",
1888                            "Illegal hextile subencoding: " + subencoding);
1889                 return false;
1890             }
1891
1892             var subrects = 0;
1893             var curr_tile = this._FBU.total_tiles - this._FBU.tiles;
1894             var tile_x = curr_tile % this._FBU.tiles_x;
1895             var tile_y = Math.floor(curr_tile / this._FBU.tiles_x);
1896             var x = this._FBU.x + tile_x * 16;
1897             var y = this._FBU.y + tile_y * 16;
1898             var w = Math.min(16, (this._FBU.x + this._FBU.width) - x);
1899             var h = Math.min(16, (this._FBU.y + this._FBU.height) - y);
1900
1901             // Figure out how much we are expecting
1902             if (subencoding & 0x01) {  // Raw
1903                 this._FBU.bytes += w * h * 4;
1904             } else {
1905                 if (subencoding & 0x02) {  // Background
1906                     this._FBU.bytes += 4;
1907                 }
1908                 if (subencoding & 0x04) {  // Foreground
1909                     this._FBU.bytes += 4;
1910                 }
1911                 if (subencoding & 0x08) {  // AnySubrects
1912                     this._FBU.bytes++;  // Since we aren't shifting it off
1913                     if (this._sock.rQwait("hextile subrects header", this._FBU.bytes)) { return false; }
1914                     subrects = rQ[rQi + this._FBU.bytes - 1];  // Peek
1915                     if (subencoding & 0x10) {  // SubrectsColoured
1916                         this._FBU.bytes += subrects * (4 + 2);
1917                     } else {
1918                         this._FBU.bytes += subrects * 2;
1919                     }
1920                 }
1921             }
1922
1923             if (this._sock.rQwait("hextile", this._FBU.bytes)) { return false; }
1924
1925             // We know the encoding and have a whole tile
1926             this._FBU.subencoding = rQ[rQi];
1927             rQi++;
1928             if (this._FBU.subencoding === 0) {
1929                 if (this._FBU.lastsubencoding & 0x01) {
1930                     // Weird: ignore blanks are RAW
1931                     Log.Debug("     Ignoring blank after RAW");
1932                 } else {
1933                     this._display.fillRect(x, y, w, h, this._FBU.background);
1934                 }
1935             } else if (this._FBU.subencoding & 0x01) {  // Raw
1936                 this._display.blitImage(x, y, w, h, rQ, rQi);
1937                 rQi += this._FBU.bytes - 1;
1938             } else {
1939                 if (this._FBU.subencoding & 0x02) {  // Background
1940                     this._FBU.background = [rQ[rQi], rQ[rQi + 1], rQ[rQi + 2], rQ[rQi + 3]];
1941                     rQi += 4;
1942                 }
1943                 if (this._FBU.subencoding & 0x04) {  // Foreground
1944                     this._FBU.foreground = [rQ[rQi], rQ[rQi + 1], rQ[rQi + 2], rQ[rQi + 3]];
1945                     rQi += 4;
1946                 }
1947
1948                 this._display.startTile(x, y, w, h, this._FBU.background);
1949                 if (this._FBU.subencoding & 0x08) {  // AnySubrects
1950                     subrects = rQ[rQi];
1951                     rQi++;
1952
1953                     for (var s = 0; s < subrects; s++) {
1954                         var color;
1955                         if (this._FBU.subencoding & 0x10) {  // SubrectsColoured
1956                             color = [rQ[rQi], rQ[rQi + 1], rQ[rQi + 2], rQ[rQi + 3]];
1957                             rQi += 4;
1958                         } else {
1959                             color = this._FBU.foreground;
1960                         }
1961                         var xy = rQ[rQi];
1962                         rQi++;
1963                         var sx = (xy >> 4);
1964                         var sy = (xy & 0x0f);
1965
1966                         var wh = rQ[rQi];
1967                         rQi++;
1968                         var sw = (wh >> 4) + 1;
1969                         var sh = (wh & 0x0f) + 1;
1970
1971                         this._display.subTile(sx, sy, sw, sh, color);
1972                     }
1973                 }
1974                 this._display.finishTile();
1975             }
1976             this._sock.set_rQi(rQi);
1977             this._FBU.lastsubencoding = this._FBU.subencoding;
1978             this._FBU.bytes = 0;
1979             this._FBU.tiles--;
1980         }
1981
1982         if (this._FBU.tiles === 0) {
1983             this._FBU.rects--;
1984         }
1985
1986         return true;
1987     },
1988
1989     TIGHT: function () {
1990         this._FBU.bytes = 1;  // compression-control byte
1991         if (this._sock.rQwait("TIGHT compression-control", this._FBU.bytes)) { return false; }
1992
1993         var checksum = function (data) {
1994             var sum = 0;
1995             for (var i = 0; i < data.length; i++) {
1996                 sum += data[i];
1997                 if (sum > 65536) sum -= 65536;
1998             }
1999             return sum;
2000         };
2001
2002         var resetStreams = 0;
2003         var streamId = -1;
2004         var decompress = function (data, expected) {
2005             for (var i = 0; i < 4; i++) {
2006                 if ((resetStreams >> i) & 1) {
2007                     this._FBU.zlibs[i].reset();
2008                     Log.Info("Reset zlib stream " + i);
2009                 }
2010             }
2011
2012             //var uncompressed = this._FBU.zlibs[streamId].uncompress(data, 0);
2013             var uncompressed = this._FBU.zlibs[streamId].inflate(data, true, expected);
2014             /*if (uncompressed.status !== 0) {
2015                 Log.Error("Invalid data in zlib stream");
2016             }*/
2017
2018             //return uncompressed.data;
2019             return uncompressed;
2020         }.bind(this);
2021
2022         var indexedToRGBX2Color = function (data, palette, width, height) {
2023             // Convert indexed (palette based) image data to RGB
2024             // TODO: reduce number of calculations inside loop
2025             var dest = this._destBuff;
2026             var w = Math.floor((width + 7) / 8);
2027             var w1 = Math.floor(width / 8);
2028
2029             /*for (var y = 0; y < height; y++) {
2030                 var b, x, dp, sp;
2031                 var yoffset = y * width;
2032                 var ybitoffset = y * w;
2033                 var xoffset, targetbyte;
2034                 for (x = 0; x < w1; x++) {
2035                     xoffset = yoffset + x * 8;
2036                     targetbyte = data[ybitoffset + x];
2037                     for (b = 7; b >= 0; b--) {
2038                         dp = (xoffset + 7 - b) * 3;
2039                         sp = (targetbyte >> b & 1) * 3;
2040                         dest[dp] = palette[sp];
2041                         dest[dp + 1] = palette[sp + 1];
2042                         dest[dp + 2] = palette[sp + 2];
2043                     }
2044                 }
2045
2046                 xoffset = yoffset + x * 8;
2047                 targetbyte = data[ybitoffset + x];
2048                 for (b = 7; b >= 8 - width % 8; b--) {
2049                     dp = (xoffset + 7 - b) * 3;
2050                     sp = (targetbyte >> b & 1) * 3;
2051                     dest[dp] = palette[sp];
2052                     dest[dp + 1] = palette[sp + 1];
2053                     dest[dp + 2] = palette[sp + 2];
2054                 }
2055             }*/
2056
2057             for (var y = 0; y < height; y++) {
2058                 var b, x, dp, sp;
2059                 for (x = 0; x < w1; x++) {
2060                     for (b = 7; b >= 0; b--) {
2061                         dp = (y * width + x * 8 + 7 - b) * 4;
2062                         sp = (data[y * w + x] >> b & 1) * 3;
2063                         dest[dp] = palette[sp];
2064                         dest[dp + 1] = palette[sp + 1];
2065                         dest[dp + 2] = palette[sp + 2];
2066                         dest[dp + 3] = 255;
2067                     }
2068                 }
2069
2070                 for (b = 7; b >= 8 - width % 8; b--) {
2071                     dp = (y * width + x * 8 + 7 - b) * 4;
2072                     sp = (data[y * w + x] >> b & 1) * 3;
2073                     dest[dp] = palette[sp];
2074                     dest[dp + 1] = palette[sp + 1];
2075                     dest[dp + 2] = palette[sp + 2];
2076                     dest[dp + 3] = 255;
2077                 }
2078             }
2079
2080             return dest;
2081         }.bind(this);
2082
2083         var indexedToRGBX = function (data, palette, width, height) {
2084             // Convert indexed (palette based) image data to RGB
2085             var dest = this._destBuff;
2086             var total = width * height * 4;
2087             for (var i = 0, j = 0; i < total; i += 4, j++) {
2088                 var sp = data[j] * 3;
2089                 dest[i] = palette[sp];
2090                 dest[i + 1] = palette[sp + 1];
2091                 dest[i + 2] = palette[sp + 2];
2092                 dest[i + 3] = 255;
2093             }
2094
2095             return dest;
2096         }.bind(this);
2097
2098         var rQi = this._sock.get_rQi();
2099         var rQ = this._sock.rQwhole();
2100         var cmode, data;
2101         var cl_header, cl_data;
2102
2103         var handlePalette = function () {
2104             var numColors = rQ[rQi + 2] + 1;
2105             var paletteSize = numColors * 3;
2106             this._FBU.bytes += paletteSize;
2107             if (this._sock.rQwait("TIGHT palette " + cmode, this._FBU.bytes)) { return false; }
2108
2109             var bpp = (numColors <= 2) ? 1 : 8;
2110             var rowSize = Math.floor((this._FBU.width * bpp + 7) / 8);
2111             var raw = false;
2112             if (rowSize * this._FBU.height < 12) {
2113                 raw = true;
2114                 cl_header = 0;
2115                 cl_data = rowSize * this._FBU.height;
2116                 //clength = [0, rowSize * this._FBU.height];
2117             } else {
2118                 // begin inline getTightCLength (returning two-item arrays is bad for performance with GC)
2119                 var cl_offset = rQi + 3 + paletteSize;
2120                 cl_header = 1;
2121                 cl_data = 0;
2122                 cl_data += rQ[cl_offset] & 0x7f;
2123                 if (rQ[cl_offset] & 0x80) {
2124                     cl_header++;
2125                     cl_data += (rQ[cl_offset + 1] & 0x7f) << 7;
2126                     if (rQ[cl_offset + 1] & 0x80) {
2127                         cl_header++;
2128                         cl_data += rQ[cl_offset + 2] << 14;
2129                     }
2130                 }
2131                 // end inline getTightCLength
2132             }
2133
2134             this._FBU.bytes += cl_header + cl_data;
2135             if (this._sock.rQwait("TIGHT " + cmode, this._FBU.bytes)) { return false; }
2136
2137             // Shift ctl, filter id, num colors, palette entries, and clength off
2138             this._sock.rQskipBytes(3);
2139             //var palette = this._sock.rQshiftBytes(paletteSize);
2140             this._sock.rQshiftTo(this._paletteBuff, paletteSize);
2141             this._sock.rQskipBytes(cl_header);
2142
2143             if (raw) {
2144                 data = this._sock.rQshiftBytes(cl_data);
2145             } else {
2146                 data = decompress(this._sock.rQshiftBytes(cl_data), rowSize * this._FBU.height);
2147             }
2148
2149             // Convert indexed (palette based) image data to RGB
2150             var rgbx;
2151             if (numColors == 2) {
2152                 rgbx = indexedToRGBX2Color(data, this._paletteBuff, this._FBU.width, this._FBU.height);
2153                 this._display.blitRgbxImage(this._FBU.x, this._FBU.y, this._FBU.width, this._FBU.height, rgbx, 0, false);
2154             } else {
2155                 rgbx = indexedToRGBX(data, this._paletteBuff, this._FBU.width, this._FBU.height);
2156                 this._display.blitRgbxImage(this._FBU.x, this._FBU.y, this._FBU.width, this._FBU.height, rgbx, 0, false);
2157             }
2158
2159
2160             return true;
2161         }.bind(this);
2162
2163         var handleCopy = function () {
2164             var raw = false;
2165             var uncompressedSize = this._FBU.width * this._FBU.height * 3;
2166             if (uncompressedSize < 12) {
2167                 raw = true;
2168                 cl_header = 0;
2169                 cl_data = uncompressedSize;
2170             } else {
2171                 // begin inline getTightCLength (returning two-item arrays is for peformance with GC)
2172                 var cl_offset = rQi + 1;
2173                 cl_header = 1;
2174                 cl_data = 0;
2175                 cl_data += rQ[cl_offset] & 0x7f;
2176                 if (rQ[cl_offset] & 0x80) {
2177                     cl_header++;
2178                     cl_data += (rQ[cl_offset + 1] & 0x7f) << 7;
2179                     if (rQ[cl_offset + 1] & 0x80) {
2180                         cl_header++;
2181                         cl_data += rQ[cl_offset + 2] << 14;
2182                     }
2183                 }
2184                 // end inline getTightCLength
2185             }
2186             this._FBU.bytes = 1 + cl_header + cl_data;
2187             if (this._sock.rQwait("TIGHT " + cmode, this._FBU.bytes)) { return false; }
2188
2189             // Shift ctl, clength off
2190             this._sock.rQshiftBytes(1 + cl_header);
2191
2192             if (raw) {
2193                 data = this._sock.rQshiftBytes(cl_data);
2194             } else {
2195                 data = decompress(this._sock.rQshiftBytes(cl_data), uncompressedSize);
2196             }
2197
2198             this._display.blitRgbImage(this._FBU.x, this._FBU.y, this._FBU.width, this._FBU.height, data, 0, false);
2199
2200             return true;
2201         }.bind(this);
2202
2203         var ctl = this._sock.rQpeek8();
2204
2205         // Keep tight reset bits
2206         resetStreams = ctl & 0xF;
2207
2208         // Figure out filter
2209         ctl = ctl >> 4;
2210         streamId = ctl & 0x3;
2211
2212         if (ctl === 0x08)       cmode = "fill";
2213         else if (ctl === 0x09)  cmode = "jpeg";
2214         else if (ctl === 0x0A)  cmode = "png";
2215         else if (ctl & 0x04)    cmode = "filter";
2216         else if (ctl < 0x04)    cmode = "copy";
2217         else return this._fail("Unexpected server message",
2218                                "Illegal tight compression received, " +
2219                                "ctl: " + ctl);
2220
2221         switch (cmode) {
2222             // fill use depth because TPIXELs drop the padding byte
2223             case "fill":  // TPIXEL
2224                 this._FBU.bytes += 3;
2225                 break;
2226             case "jpeg":  // max clength
2227                 this._FBU.bytes += 3;
2228                 break;
2229             case "png":  // max clength
2230                 this._FBU.bytes += 3;
2231                 break;
2232             case "filter":  // filter id + num colors if palette
2233                 this._FBU.bytes += 2;
2234                 break;
2235             case "copy":
2236                 break;
2237         }
2238
2239         if (this._sock.rQwait("TIGHT " + cmode, this._FBU.bytes)) { return false; }
2240
2241         // Determine FBU.bytes
2242         switch (cmode) {
2243             case "fill":
2244                 // skip ctl byte
2245                 this._display.fillRect(this._FBU.x, this._FBU.y, this._FBU.width, this._FBU.height, [rQ[rQi + 3], rQ[rQi + 2], rQ[rQi + 1]], false);
2246                 this._sock.rQskipBytes(4);
2247                 break;
2248             case "png":
2249             case "jpeg":
2250                 // begin inline getTightCLength (returning two-item arrays is for peformance with GC)
2251                 var cl_offset = rQi + 1;
2252                 cl_header = 1;
2253                 cl_data = 0;
2254                 cl_data += rQ[cl_offset] & 0x7f;
2255                 if (rQ[cl_offset] & 0x80) {
2256                     cl_header++;
2257                     cl_data += (rQ[cl_offset + 1] & 0x7f) << 7;
2258                     if (rQ[cl_offset + 1] & 0x80) {
2259                         cl_header++;
2260                         cl_data += rQ[cl_offset + 2] << 14;
2261                     }
2262                 }
2263                 // end inline getTightCLength
2264                 this._FBU.bytes = 1 + cl_header + cl_data;  // ctl + clength size + jpeg-data
2265                 if (this._sock.rQwait("TIGHT " + cmode, this._FBU.bytes)) { return false; }
2266
2267                 // We have everything, render it
2268                 this._sock.rQskipBytes(1 + cl_header);  // shift off clt + compact length
2269                 data = this._sock.rQshiftBytes(cl_data);
2270                 this._display.imageRect(this._FBU.x, this._FBU.y, "image/" + cmode, data);
2271                 break;
2272             case "filter":
2273                 var filterId = rQ[rQi + 1];
2274                 if (filterId === 1) {
2275                     if (!handlePalette()) { return false; }
2276                 } else {
2277                     // Filter 0, Copy could be valid here, but servers don't send it as an explicit filter
2278                     // Filter 2, Gradient is valid but not use if jpeg is enabled
2279                     this._fail("Unexpected server message",
2280                                "Unsupported tight subencoding received, " +
2281                                "filter: " + filterId);
2282                 }
2283                 break;
2284             case "copy":
2285                 if (!handleCopy()) { return false; }
2286                 break;
2287         }
2288
2289
2290         this._FBU.bytes = 0;
2291         this._FBU.rects--;
2292
2293         return true;
2294     },
2295
2296     last_rect: function () {
2297         this._FBU.rects = 0;
2298         return true;
2299     },
2300
2301     ExtendedDesktopSize: function () {
2302         this._FBU.bytes = 1;
2303         if (this._sock.rQwait("ExtendedDesktopSize", this._FBU.bytes)) { return false; }
2304
2305         this._supportsSetDesktopSize = true;
2306         this._setCapability("resize", true);
2307
2308         var number_of_screens = this._sock.rQpeek8();
2309
2310         this._FBU.bytes = 4 + (number_of_screens * 16);
2311         if (this._sock.rQwait("ExtendedDesktopSize", this._FBU.bytes)) { return false; }
2312
2313         this._sock.rQskipBytes(1);  // number-of-screens
2314         this._sock.rQskipBytes(3);  // padding
2315
2316         for (var i = 0; i < number_of_screens; i += 1) {
2317             // Save the id and flags of the first screen
2318             if (i === 0) {
2319                 this._screen_id = this._sock.rQshiftBytes(4);    // id
2320                 this._sock.rQskipBytes(2);                       // x-position
2321                 this._sock.rQskipBytes(2);                       // y-position
2322                 this._sock.rQskipBytes(2);                       // width
2323                 this._sock.rQskipBytes(2);                       // height
2324                 this._screen_flags = this._sock.rQshiftBytes(4); // flags
2325             } else {
2326                 this._sock.rQskipBytes(16);
2327             }
2328         }
2329
2330         /*
2331          * The x-position indicates the reason for the change:
2332          *
2333          *  0 - server resized on its own
2334          *  1 - this client requested the resize
2335          *  2 - another client requested the resize
2336          */
2337
2338         // We need to handle errors when we requested the resize.
2339         if (this._FBU.x === 1 && this._FBU.y !== 0) {
2340             var msg = "";
2341             // The y-position indicates the status code from the server
2342             switch (this._FBU.y) {
2343             case 1:
2344                 msg = "Resize is administratively prohibited";
2345                 break;
2346             case 2:
2347                 msg = "Out of resources";
2348                 break;
2349             case 3:
2350                 msg = "Invalid screen layout";
2351                 break;
2352             default:
2353                 msg = "Unknown reason";
2354                 break;
2355             }
2356             this._notification("Server did not accept the resize request: "
2357                                + msg, 'normal');
2358         } else {
2359             this._resize(this._FBU.width, this._FBU.height);
2360         }
2361
2362         this._FBU.bytes = 0;
2363         this._FBU.rects -= 1;
2364         return true;
2365     },
2366
2367     DesktopSize: function () {
2368         this._resize(this._FBU.width, this._FBU.height);
2369         this._FBU.bytes = 0;
2370         this._FBU.rects -= 1;
2371         return true;
2372     },
2373
2374     Cursor: function () {
2375         Log.Debug(">> set_cursor");
2376         var x = this._FBU.x;  // hotspot-x
2377         var y = this._FBU.y;  // hotspot-y
2378         var w = this._FBU.width;
2379         var h = this._FBU.height;
2380
2381         var pixelslength = w * h * 4;
2382         var masklength = Math.floor((w + 7) / 8) * h;
2383
2384         this._FBU.bytes = pixelslength + masklength;
2385         if (this._sock.rQwait("cursor encoding", this._FBU.bytes)) { return false; }
2386
2387         this._display.changeCursor(this._sock.rQshiftBytes(pixelslength),
2388                                    this._sock.rQshiftBytes(masklength),
2389                                    x, y, w, h);
2390
2391         this._FBU.bytes = 0;
2392         this._FBU.rects--;
2393
2394         Log.Debug("<< set_cursor");
2395         return true;
2396     },
2397
2398     QEMUExtendedKeyEvent: function () {
2399         this._FBU.rects--;
2400
2401         // Old Safari doesn't support creating keyboard events
2402         try {
2403             var keyboardEvent = document.createEvent("keyboardEvent");
2404             if (keyboardEvent.code !== undefined) {
2405                 this._qemuExtKeyEventSupported = true;
2406             }
2407         } catch (err) {
2408         }
2409     },
2410 };