public void establishKey() throws RdesktopException, IOException, CryptoException {
RdpPacket_Localised buffer;
int flags = SEC_CLIENT_RANDOM;
if (readCert) {
// RDP5-style encryption, use old code for now
int length = SEC_MODULUS_SIZE + SEC_PADDING_SIZE;
buffer = this.init(flags, 76);
buffer.setLittleEndian32(length);
buffer.copyFromByteArray(this.sec_crypted_random, 0, buffer.getPosition(), SEC_MODULUS_SIZE);
buffer.incrementPosition(SEC_MODULUS_SIZE);
} else {
int length = server_public_key_len + SEC_PADDING_SIZE;
buffer = this.init(flags, length + 4);
buffer.setLittleEndian32(length);
buffer.copyFromByteArray(
this.sec_crypted_random, 0, buffer.getPosition(), server_public_key_len);
buffer.incrementPosition(server_public_key_len);
}
buffer.incrementPosition(SEC_PADDING_SIZE);
buffer.markEnd();
this.send(buffer, flags);
}
/**
* Prepare data as a Secure PDU and pass down to the MCS layer
*
* @param sec_data Data to send
* @param flags Encryption flags
* @param channel Channel over which to send data
* @throws RdesktopException
* @throws IOException
* @throws CryptoException
*/
public void send_to_channel(RdpPacket_Localised sec_data, int flags, int channel)
throws RdesktopException, IOException, CryptoException {
int datalength = 0;
byte[] signature = null;
byte[] data;
byte[] buffer;
sec_data.setPosition(sec_data.getHeader(RdpPacket.SECURE_HEADER));
if (this.licenceIssued == false || (flags & SEC_ENCRYPT) != 0) {
sec_data.setLittleEndian32(flags);
}
if (Options.debug_hexdump) {
int length = sec_data.getEnd() - sec_data.getPosition();
byte[] packet = new byte[length];
sec_data.copyToByteArray(
packet, 0, sec_data.getPosition(), sec_data.getEnd() - sec_data.getPosition());
System.out.println("Sending packet:");
System.out.println(net.propero.rdp.tools.HexDump.dumpHexString(packet));
}
if ((flags & SEC_ENCRYPT) != 0) {
flags &= ~SEC_ENCRYPT;
datalength = sec_data.getEnd() - sec_data.getPosition() - 8;
data = new byte[datalength];
buffer = null;
sec_data.copyToByteArray(data, 0, sec_data.getPosition() + 8, datalength);
signature = this.sign(this.sec_sign_key, 8, this.keylength, data, datalength);
buffer = this.encrypt(data, datalength);
sec_data.copyFromByteArray(signature, 0, sec_data.getPosition(), 8);
sec_data.copyFromByteArray(buffer, 0, sec_data.getPosition() + 8, datalength);
}
// McsLayer.send(sec_data);
McsLayer.send_to_channel(sec_data, channel);
}
/**
* Receive a Secure layer PDU from the MCS layer
*
* @return Packet representing received Secure PDU
* @throws RdesktopException
* @throws IOException
* @throws CryptoException
* @throws OrderException
*/
public RdpPacket_Localised receive()
throws RdesktopException, IOException, CryptoException, OrderException {
int sec_flags = 0;
RdpPacket_Localised buffer = null;
while (true) {
int[] channel = new int[1];
buffer = McsLayer.receive(channel);
if (buffer == null) return null;
buffer.setHeader(RdpPacket.SECURE_HEADER);
if (Constants.encryption || (!this.licenceIssued)) {
sec_flags = buffer.getLittleEndian32();
if ((sec_flags & SEC_LICENCE_NEG) != 0) {
licence.process(buffer);
continue;
}
if ((sec_flags & SEC_ENCRYPT) != 0) {
buffer.incrementPosition(8); // signature
byte[] data = new byte[buffer.size() - buffer.getPosition()];
buffer.copyToByteArray(data, 0, buffer.getPosition(), data.length);
byte[] packet = this.decrypt(data);
buffer.copyFromByteArray(packet, 0, buffer.getPosition(), packet.length);
// buffer.setStart(buffer.getPosition());
// return buffer;
}
}
if (channel[0] != MCS.MCS_GLOBAL_CHANNEL) {
channels.channel_process(buffer, channel[0]);
continue;
}
buffer.setStart(buffer.getPosition());
return buffer;
}
}
