rfbproto.java

JAVA版vpn客户端,是在web上实现远程访问的最佳方式.

    int reasonLen = is.readInt();
    byte[] reason = new byte[reasonLen];
    readFully(reason);
    throw new Exception(new String(reason));
  }

  //
  // Initialize capability lists (TightVNC protocol extensions).
  //

  void initCapabilities() {
    tunnelCaps    = new CapsContainer();
    authCaps      = new CapsContainer();
    serverMsgCaps = new CapsContainer();
    clientMsgCaps = new CapsContainer();
    encodingCaps  = new CapsContainer();

    // Supported authentication methods
    authCaps.add(AuthNone, StandardVendor, SigAuthNone,
		 "No authentication");
    authCaps.add(AuthVNC, StandardVendor, SigAuthVNC,
		 "Standard VNC password authentication");

    // Supported encoding types
    encodingCaps.add(EncodingCopyRect, StandardVendor,
		     SigEncodingCopyRect, "Standard CopyRect encoding");
    encodingCaps.add(EncodingRRE, StandardVendor,
		     SigEncodingRRE, "Standard RRE encoding");
    encodingCaps.add(EncodingCoRRE, StandardVendor,
		     SigEncodingCoRRE, "Standard CoRRE encoding");
    encodingCaps.add(EncodingHextile, StandardVendor,
		     SigEncodingHextile, "Standard Hextile encoding");
    encodingCaps.add(EncodingZRLE, StandardVendor,
		     SigEncodingZRLE, "Standard ZRLE encoding");
    encodingCaps.add(EncodingZlib, TridiaVncVendor,
		     SigEncodingZlib, "Zlib encoding");
    encodingCaps.add(EncodingTight, TightVncVendor,
		     SigEncodingTight, "Tight encoding");

    // Supported pseudo-encoding types
    encodingCaps.add(EncodingCompressLevel0, TightVncVendor,
		     SigEncodingCompressLevel0, "Compression level");
    encodingCaps.add(EncodingQualityLevel0, TightVncVendor,
		     SigEncodingQualityLevel0, "JPEG quality level");
    encodingCaps.add(EncodingXCursor, TightVncVendor,
		     SigEncodingXCursor, "X-style cursor shape update");
    encodingCaps.add(EncodingRichCursor, TightVncVendor,
		     SigEncodingRichCursor, "Rich-color cursor shape update");
    encodingCaps.add(EncodingPointerPos, TightVncVendor,
		     SigEncodingPointerPos, "Pointer position update");
    encodingCaps.add(EncodingLastRect, TightVncVendor,
		     SigEncodingLastRect, "LastRect protocol extension");
    encodingCaps.add(EncodingNewFBSize, TightVncVendor,
		     SigEncodingNewFBSize, "Framebuffer size change");
  }

  //
  // Setup tunneling (TightVNC protocol extensions)
  //

  void setupTunneling() throws IOException {
    int nTunnelTypes = is.readInt();
    if (nTunnelTypes != 0) {
      readCapabilityList(tunnelCaps, nTunnelTypes);

      // We don't support tunneling yet.
      writeInt(NoTunneling);
    }
  }

  //
  // Negotiate authentication scheme (TightVNC protocol extensions)
  //

  int negotiateAuthenticationTight() throws Exception {
    int nAuthTypes = is.readInt();
    if (nAuthTypes == 0)
      return AuthNone;

    readCapabilityList(authCaps, nAuthTypes);
    for (int i = 0; i < authCaps.numEnabled(); i++) {
      int authType = authCaps.getByOrder(i);
      if (authType == AuthNone || authType == AuthVNC) {
	writeInt(authType);
	return authType;
      }
    }
    throw new Exception("No suitable authentication scheme found");
  }

  //
  // Read a capability list (TightVNC protocol extensions)
  //

  void readCapabilityList(CapsContainer caps, int count) throws IOException {
    int code;
    byte[] vendor = new byte[4];
    byte[] name = new byte[8];
    for (int i = 0; i < count; i++) {
      code = is.readInt();
      readFully(vendor);
      readFully(name);
      caps.enable(new CapabilityInfo(code, vendor, name));
    }
  }

  //
  // Write a 32-bit integer into the output stream.
  //

  void writeInt(int value) throws IOException {
    byte[] b = new byte[4];
    b[0] = (byte) ((value >> 24) & 0xff);
    b[1] = (byte) ((value >> 16) & 0xff);
    b[2] = (byte) ((value >> 8) & 0xff);
    b[3] = (byte) (value & 0xff);
    os.write(b);
  }

  //
  // Write the client initialisation message
  //

  void writeClientInit() throws IOException {
    if (viewer.options.shareDesktop) {
      os.write(1);
    } else {
      os.write(0);
    }
    viewer.options.disableShareDesktop();
  }


  //
  // Read the server initialisation message
  //

  String desktopName;
  int framebufferWidth, framebufferHeight;
  int bitsPerPixel, depth;
  boolean bigEndian, trueColour;
  int redMax, greenMax, blueMax, redShift, greenShift, blueShift;

  void readServerInit() throws IOException {
    framebufferWidth = is.readUnsignedShort();
    framebufferHeight = is.readUnsignedShort();
    bitsPerPixel = is.readUnsignedByte();
    depth = is.readUnsignedByte();
    bigEndian = (is.readUnsignedByte() != 0);
    trueColour = (is.readUnsignedByte() != 0);
    redMax = is.readUnsignedShort();
    greenMax = is.readUnsignedShort();
    blueMax = is.readUnsignedShort();
    redShift = is.readUnsignedByte();
    greenShift = is.readUnsignedByte();
    blueShift = is.readUnsignedByte();
    byte[] pad = new byte[3];
    readFully(pad);
    int nameLength = is.readInt();
    byte[] name = new byte[nameLength];
    readFully(name);
    desktopName = new String(name);

    // Read interaction capabilities (TightVNC protocol extensions)
    if (protocolTightVNC) {
      int nServerMessageTypes = is.readUnsignedShort();
      int nClientMessageTypes = is.readUnsignedShort();
      int nEncodingTypes = is.readUnsignedShort();
      is.readUnsignedShort();
      readCapabilityList(serverMsgCaps, nServerMessageTypes);
      readCapabilityList(clientMsgCaps, nClientMessageTypes);
      readCapabilityList(encodingCaps, nEncodingTypes);
    }

    inNormalProtocol = true;
  }


  //
  // Create session file and write initial protocol messages into it.
  //

  void startSession(String fname) throws IOException {
    rec = new SessionRecorder(fname);
    rec.writeHeader();
    rec.write(versionMsg_3_3.getBytes());
    rec.writeIntBE(SecTypeNone);
    rec.writeShortBE(framebufferWidth);
    rec.writeShortBE(framebufferHeight);
    byte[] fbsServerInitMsg =	{
      32, 24, 0, 1, 0,
      (byte)0xFF, 0, (byte)0xFF, 0, (byte)0xFF,
      16, 8, 0, 0, 0, 0
    };
    rec.write(fbsServerInitMsg);
    rec.writeIntBE(desktopName.length());
    rec.write(desktopName.getBytes());
    numUpdatesInSession = 0;

    // FIXME: If there were e.g. ZRLE updates only, that should not
    //        affect recording of Zlib and Tight updates. So, actually
    //        we should maintain separate flags for Zlib, ZRLE and
    //        Tight, instead of one ``wereZlibUpdates'' variable.
    //
    if (wereZlibUpdates)
      recordFromBeginning = false;

    zlibWarningShown = false;
    tightWarningShown = false;
  }

  //
  // Close session file.
  //

  void closeSession() throws IOException {
    if (rec != null) {
      rec.close();
      rec = null;
    }
  }


  //
  // Set new framebuffer size
  //

  void setFramebufferSize(int width, int height) {
    framebufferWidth = width;
    framebufferHeight = height;
  }


  //
  // Read the server message type
  //

  int readServerMessageType() throws IOException {
    int msgType = is.readUnsignedByte();

    // If the session is being recorded:
    if (rec != null) {
      if (msgType == Bell) {	// Save Bell messages in session files.
	rec.writeByte(msgType);
	if (numUpdatesInSession > 0)
	  rec.flush();
      }
    }

    return msgType;
  }


  //
  // Read a FramebufferUpdate message
  //

  int updateNRects;

  void readFramebufferUpdate() throws IOException {
    is.readByte();
    updateNRects = is.readUnsignedShort();

    // If the session is being recorded:
    if (rec != null) {
      rec.writeByte(FramebufferUpdate);
      rec.writeByte(0);
      rec.writeShortBE(updateNRects);
    }

    numUpdatesInSession++;
  }

  // Read a FramebufferUpdate rectangle header

  int updateRectX, updateRectY, updateRectW, updateRectH, updateRectEncoding;

  void readFramebufferUpdateRectHdr() throws Exception {
    updateRectX = is.readUnsignedShort();
    updateRectY = is.readUnsignedShort();
    updateRectW = is.readUnsignedShort();
    updateRectH = is.readUnsignedShort();
    updateRectEncoding = is.readInt();

    if (updateRectEncoding == EncodingZlib ||
        updateRectEncoding == EncodingZRLE ||
	updateRectEncoding == EncodingTight)
      wereZlibUpdates = true;

    // If the session is being recorded:
    if (rec != null) {
      if (numUpdatesInSession > 1)
	rec.flush();		// Flush the output on each rectangle.
      rec.writeShortBE(updateRectX);
      rec.writeShortBE(updateRectY);
      rec.writeShortBE(updateRectW);
      rec.writeShortBE(updateRectH);
      if (updateRectEncoding == EncodingZlib && !recordFromBeginning) {
	// Here we cannot write Zlib-encoded rectangles because the
	// decoder won't be able to reproduce zlib stream state.
	if (!zlibWarningShown) {
	  System.out.println("Warning: Raw encoding will be used " +
			     "instead of Zlib in recorded session.");
	  zlibWarningShown = true;
	}
	rec.writeIntBE(EncodingRaw);
      } else {
	rec.writeIntBE(updateRectEncoding);
	if (updateRectEncoding == EncodingTight && !recordFromBeginning &&
	    !tightWarningShown) {
	  System.out.println("Warning: Re-compressing Tight-encoded " +
			     "updates for session recording.");
	  tightWarningShown = true;
	}
      }
    }

    if (updateRectEncoding < 0 || updateRectEncoding > MaxNormalEncoding)
      return;

    if (updateRectX + updateRectW > framebufferWidth ||
	updateRectY + updateRectH > framebufferHeight) {
      throw new Exception("Framebuffer update rectangle too large: " +
			  updateRectW + "x" + updateRectH + " at (" +
			  updateRectX + "," + updateRectY + ")");
    }
  }

  // Read CopyRect source X and Y.

  int copyRectSrcX, copyRectSrcY;

  void readCopyRect() throws IOException {
    copyRectSrcX = is.readUnsignedShort();
    copyRectSrcY = is.readUnsignedShort();

    // If the session is being recorded:
    if (rec != null) {
      rec.writeShortBE(copyRectSrcX);
      rec.writeShortBE(copyRectSrcY);
    }
  }


  //
  // Read a ServerCutText message
  //

  String readServerCutText() throws IOException {
    byte[] pad = new byte[3];
    readFully(pad);
    int len = is.readInt();
    byte[] text = new byte[len];
    readFully(text);
    return new String(text);
  }


  //
  // Read an integer in compact representation (1..3 bytes).
  // Such format is used as a part of the Tight encoding.
  // Also, this method records data if session recording is active and
  // the viewer's recordFromBeginning variable is set to true.
  //

  int readCompactLen() throws IOException {
    int[] portion = new int[3];
    portion[0] = is.readUnsignedByte();
    int byteCount = 1;
    int len = portion[0] & 0x7F;
    if ((portion[0] & 0x80) != 0) {
      portion[1] = is.readUnsignedByte();
      byteCount++;
      len |= (portion[1] & 0x7F) << 7;
      if ((portion[1] & 0x80) != 0) {
	portion[2] = is.readUnsignedByte();
	byteCount++;
	len |= (portion[2] & 0xFF) << 14;
      }
    }

    if (rec != null && recordFromBeginning)
      for (int i = 0; i < byteCount; i++)
	rec.writeByte(portion[i]);

    return len;
  }


  //
  // Write a FramebufferUpdateRequest message
  //

  void writeFramebufferUpdateRequest(int x, int y, int w, int h,
				     boolean incremental)
       throws IOException
  {
    byte[] b = new byte[10];

    b[0] = (byte) FramebufferUpdateRequest;
    b[1] = (byte) (incremental ? 1 : 0);
    b[2] = (byte) ((x >> 8) & 0xff);
    b[3] = (byte) (x & 0xff);
    b[4] = (byte) ((y >> 8) & 0xff);
    b[5] = (byte) (y & 0xff);
    b[6] = (byte) ((w >> 8) & 0xff);
    b[7] = (byte) (w & 0xff);
    b[8] = (byte) ((h >> 8) & 0xff);
    b[9] = (byte) (h & 0xff);

    os.write(b);
  }


  //
  // Write a SetPixelFormat message
  //

  void writeSetPixelFormat(int bitsPerPixel, int depth, boolean bigEndian,
			   boolean trueColour,
			   int redMax, int greenMax, int blueMax,
			   int redShift, int greenShift, int blueShift)
       throws IOException
  {
    byte[] b = new byte[20];

    b[0]  = (byte) SetPixelFormat;
    b[4]  = (byte) bitsPerPixel;
    b[5]  = (byte) depth;
    b[6]  = (byte) (bigEndian ? 1 : 0);
    b[7]  = (byte) (trueColour ? 1 : 0);
    b[8]  = (byte) ((redMax >> 8) & 0xff);
    b[9]  = (byte) (redMax & 0xff);
    b[10] = (byte) ((greenMax >> 8) & 0xff);
    b[11] = (byte) (greenMax & 0xff);
    b[12] = (byte) ((blueMax >> 8) & 0xff);
    b[13] = (byte) (blueMax & 0xff);
    b[14] = (byte) redShift;