// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements. See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership. The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the License for the
// specific language governing permissions and limitations
// under the License.
package rdpclient.rdp;
import streamer.BaseElement;
import streamer.ByteBuffer;
import streamer.Link;
/**
* @see http://msdn.microsoft.com/en-us/library/cc240621.aspx
*/
public class ServerFastPath extends BaseElement {
/**
* TPKT protocol version (first byte).
*/
public static final int PROTOCOL_TPKT = 0x03;
/**
* Fast path protocol version (first two bits of first byte).
*/
public static final int PROTOCOL_FASTPATH = 0x00;
/**
* CredSSP packets.
*/
public static final int PROTOCOL_CREDSSP = 0x30;
/**
* TPKT packets will be pushed to that pad.
*/
public static final String TPKT_PAD = "tpkt";
/**
* CredSSP packets will be pushed to same pad as TPKT, because they are part
* of slow-path initialization sequence.
*/
public static final String CREDSSP_PAD = "tpkt";
private static final String ORDERS_PAD = "orders";
private static final String BITMAP_PAD = "bitmap";
private static final String PALETTE_PAD = "palette";
/**
* Indicates that packet contains 8 byte secure checksum at top of packet. Top
* two bits of first byte.
*/
public static final int FASTPATH_OUTPUT_SECURE_CHECKSUM = 1;
/**
* Indicates that packet contains 8 byte secure checksum at top of packet and
* packet content is encrypted. Top two bits of first byte.
*/
public static final int FASTPATH_OUTPUT_ENCRYPTED = 2;
public static final int FASTPATH_UPDATETYPE_ORDERS = 0;
public static final int FASTPATH_UPDATETYPE_BITMAP = 1;
public static final int FASTPATH_UPDATETYPE_PALETTE = 2;
public static final int FASTPATH_UPDATETYPE_SYNCHRONIZE = 3;
public static final int FASTPATH_UPDATETYPE_SURFCMDS = 4;
public static final int FASTPATH_UPDATETYPE_PTR_NULL = 5;
public static final int FASTPATH_UPDATETYPE_PTR_DEFAULT = 6;
public static final int FASTPATH_UPDATETYPE_PTR_POSITION = 8;
public static final int FASTPATH_UPDATETYPE_COLOR = 9;
public static final int FASTPATH_UPDATETYPE_CACHED = 0xa;
public static final int FASTPATH_UPDATETYPE_POINTER = 0xb;
public static final int FASTPATH_FRAGMENT_SINGLE = 0;
public static final int FASTPATH_FRAGMENT_LAST = 1;
public static final int FASTPATH_FRAGMENT_FIRST = 2;
public static final int FASTPATH_FRAGMENT_NEXT = 3;
public static final int FASTPATH_OUTPUT_COMPRESSION_USED = 2;
public ServerFastPath(String id) {
super(id);
}
@Override
public void handleData(ByteBuffer buf, Link link) {
if (buf == null)
return;
if (verbose)
System.out.println("[" + this + "] INFO: Data received: " + buf + ".");
// * DEBUG */System.out.println(buf.toHexString(buf.length));
// We need at 4 bytes to read packet type (TPKT or FastPath) and packet
// length
if (!cap(buf, 4, UNLIMITED, link, false))
return;
int typeAndFlags = buf.readUnsignedByte();
switch (typeAndFlags) {
case PROTOCOL_TPKT: // 0x03
handleTpkt(buf, link);
break;
case PROTOCOL_CREDSSP: // 0x30, potential clash with FastPath
handleCredSSP(buf, link);
break;
default: // (value & 0x03) == 0x00
case PROTOCOL_FASTPATH:
handleFastPath(buf, link, typeAndFlags);
break;
}
}
private void handleTpkt(ByteBuffer buf, Link link) {
// Reserved
buf.skipBytes(1);
// Read TPKT length
int length = buf.readUnsignedShort();
if (!cap(buf, length, length, link, false))
// Wait for full packet to arrive
return;
int payloadLength = length - buf.cursor;
// Extract payload
ByteBuffer outBuf = buf.slice(buf.cursor, payloadLength, true);
buf.unref();
if (verbose) {
outBuf.putMetadata("source", this);
}
pushDataToPad(TPKT_PAD, outBuf);
}
private void handleCredSSP(ByteBuffer buf, Link link) {
if (verbose)
System.out.println("[" + this + "] INFO: CredSSP data received: " + buf + ".");
// Store header position: will parse whole header later in BER format parser
int headerPosition = buf.cursor - 1;
long payloadLength = buf.readBerLength();
if (payloadLength > 10 * 1024)
throw new RuntimeException("[" + this + "] ERROR: CredSSP packets seems to be too long: " + payloadLength + "bytes. Data: " + buf + ".");
// Length is the size of payload, so we need to append size of header
int headerLength = buf.cursor - headerPosition;
int packetLength = (int)payloadLength + headerLength;
if (!cap(buf, packetLength, packetLength, link, false))
// Wait for full packet to arrive
return;
// Extract payload (with header)
ByteBuffer outBuf = buf.slice(headerPosition, packetLength, true);
buf.unref();
if (verbose) {
outBuf.putMetadata("source", this);
}
pushDataToPad(CREDSSP_PAD, outBuf);
}
private void handleFastPath(ByteBuffer buf, Link link, int typeAndFlags) {
// Number of bytes in updateData field (including header (1+1 or 2
// bytes))
int length = buf.readVariableUnsignedShort();
if (!cap(buf, length, length, link, false))
// Wait for full packet to arrive
return;
int type = typeAndFlags & 0x3;
int securityFlags = (typeAndFlags >> 6) & 0x3;
// Assertions
{
if (type != PROTOCOL_FASTPATH)
throw new RuntimeException("Unknown protocol. Expected protocol: 0 (FastPath). Actual protocol: " + type + ", data: " + buf + ".");
switch (securityFlags) {
case FASTPATH_OUTPUT_SECURE_CHECKSUM:
// TODO
throw new RuntimeException("Secure checksum is not supported in FastPath packets.");
case FASTPATH_OUTPUT_ENCRYPTED:
// TODO
throw new RuntimeException("Encryption is not supported in FastPath packets.");
}
}
// TODO: optional FIPS information, when FIPS is selected
// TODO: optional data signature (checksum), when checksum or FIPS is
// selected
// Array of FastPath update fields
while (buf.cursor < buf.length) {
int updateHeader = buf.readUnsignedByte();
int size = buf.readUnsignedShortLE();
int updateCode = updateHeader & 0xf;
int fragmentation = (updateHeader >> 4) & 0x3;
int compression = (updateHeader >> 6) & 0x3;
if (verbose)
System.out.println("[" + this + "] INFO: FastPath update received. UpdateCode: " + updateCode + ", fragmentation: " + fragmentation + ", compression: "
+ compression + ", size: " + size + ".");
ByteBuffer data = buf.readBytes(size);
buf.putMetadata("fragmentation", fragmentation);
buf.putMetadata("compression", compression);
switch (updateCode) {
case FASTPATH_UPDATETYPE_ORDERS:
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_ORDERS.");
pushDataToPad(ORDERS_PAD, data);
break;
case FASTPATH_UPDATETYPE_BITMAP:
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_BITMAP.");
pushDataToPad(BITMAP_PAD, data);
break;
case FASTPATH_UPDATETYPE_PALETTE:
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_PALETTE.");
pushDataToPad(PALETTE_PAD, data);
break;
case FASTPATH_UPDATETYPE_SYNCHRONIZE:
// @see http://msdn.microsoft.com/en-us/library/cc240625.aspx
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_SYNCHRONIZE.");
data.unref();
if (size != 0)
throw new RuntimeException("Size of FastPath synchronize packet must be 0. UpdateCode: " + updateCode + ", fragmentation: " + fragmentation
+ ", compression: " + compression + ", size: " + size + ", data: " + data + ".");
break;
case FASTPATH_UPDATETYPE_SURFCMDS:
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_SURFCMDS.");
break;
case FASTPATH_UPDATETYPE_PTR_NULL:
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_PTR_NULL.");
break;
case FASTPATH_UPDATETYPE_PTR_DEFAULT:
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_PTR_DEFAULT.");
break;
case FASTPATH_UPDATETYPE_PTR_POSITION:
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_PTR_POSITION.");
break;
case FASTPATH_UPDATETYPE_COLOR:
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_COLOR.");
break;
case FASTPATH_UPDATETYPE_CACHED:
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_CACHED.");
break;
case FASTPATH_UPDATETYPE_POINTER:
if (verbose)
System.out.println("[" + this + "] INFO: FASTPATH_UPDATETYPE_POINTER.");
break;
default:
throw new RuntimeException("Unknown FastPath update. UpdateCode: " + updateCode + ", fragmentation: " + fragmentation + ", compression: " + compression
+ ", size: " + size + ", data: " + data + ".");
}
buf.unref();
}
}
}