/// <summary>
/// Send a SYN and ACK diagram
/// </summary>
/// <param name="initSequenceNumber">Specify an initial sequence number</param>
/// <returns></returns>
public bool SendSynAndAckPacket(uint? initSequenceNumber = null, uUdpVer_Values? version = null)
{
if (Connected) return false;
RdpeudpPacket SynAndAckPacket = new RdpeudpPacket();
SynAndAckPacket.fecHeader.snSourceAck = SnSourceAck;
SynAndAckPacket.fecHeader.uReceiveWindowSize = UReceiveWindowSize;
SynAndAckPacket.fecHeader.uFlags = RDPUDP_FLAG.RDPUDP_FLAG_SYN | RDPUDP_FLAG.RDPUDP_FLAG_ACK;
if(version != null)
{
SynAndAckPacket.fecHeader.uFlags |= RDPUDP_FLAG.RDPUDP_FLAG_SYNEX;
SynAndAckPacket.SynDataEx = CreateSynExData((uUdpVer_Values)version);
}
SynAndAckPacket.SynData = CreateSynData(initSequenceNumber);
SendPacket(SynAndAckPacket);
// Set the OutSnAckOfAcksSeqNum value, number from which the receive thread decoding the state of the send packet.
OutSnAckOfAcksSeqNum = SynAndAckPacket.SynData.Value.snInitialSequenceNumber + 1;
return true;
}
/// <summary>
/// Establish a UDP connection.
/// </summary>
/// <param name="udpTransportMode">Transport mode: Reliable or Lossy.</param>
/// <param name="timeout">Wait time.</param>
/// <param name="verifyPacket">Whether verify the received packet.</param>
/// <returns>The accepted socket.</returns>
private RdpeudpSocket EstablishUDPConnection(TransportMode udpTransportMode, TimeSpan timeout, bool verifyPacket = false, bool autoHanlde = false, uUdpVer_Values? uUdpVer =null)
{
// Start UDP listening.
if(rdpeudpServer == null)
rdpeudpServer = new RdpeudpServer((IPEndPoint)this.rdpbcgrAdapter.SessionContext.LocalIdentity, autoHanlde);
if(!rdpeudpServer.Running)
rdpeudpServer.Start();
// Send a Server Initiate Multitransport Request PDU.
byte[] securityCookie = new byte[16];
Random rnd = new Random();
rnd.NextBytes(securityCookie);
Multitransport_Protocol_value requestedProtocol = Multitransport_Protocol_value.INITITATE_REQUEST_PROTOCOL_UDPFECR;
if (udpTransportMode == TransportMode.Lossy)
{
requestedProtocol = Multitransport_Protocol_value.INITITATE_REQUEST_PROTOCOL_UDPFECL;
}
this.rdpbcgrAdapter.SendServerInitiateMultitransportRequestPDU(++this.multitransportRequestId, requestedProtocol, securityCookie);
// Create a UDP socket.
RdpeudpServerSocket rdpudpSocket = rdpeudpServer.CreateSocket(((IPEndPoint)this.rdpbcgrAdapter.SessionContext.Identity).Address, udpTransportMode, timeout);
if (rdpudpSocket == null)
{
this.Site.Assert.Fail("Failed to create a UDP socket for the Client : {0}", ((IPEndPoint)this.rdpbcgrAdapter.SessionContext.Identity).Address);
}
if (udpTransportMode == TransportMode.Reliable)
{
this.rdpeudpSocketR = rdpudpSocket;
}
else
{
this.rdpeudpSocketL = rdpudpSocket;
}
// Expect a SYN packet.
RdpeudpPacket synPacket = rdpudpSocket.ExpectSynPacket(timeout);
if (synPacket == null)
{
this.Site.Assert.Fail("Time out when waiting for the SYN packet");
}
// Verify the SYN packet.
if (verifyPacket)
{
VerifySYNPacket(synPacket, udpTransportMode);
}
// Send a SYN and ACK packet.
if (this.clientRdpudpVerfionInfoValidFlag == uSynExFlags_Values.RDPUDP_VERSION_INFO_VALID)
{
//Section 3.1.5.1.3: The uUdpVer field MUST be set to the highest RDP-UDP protocol version supported by both endpoints.
uUdpVer = uUdpVer > this.clientUUdpVer ? this.clientUUdpVer : uUdpVer;
SendSynAndAckPacket(udpTransportMode, SynAndAck_InvalidType.None, initSequenceNumber, uUdpVer);
}
else if(this.clientRdpudpVerfionInfoValidFlag == uSynExFlags_Values.None)
{
//Section 3.1.5.1.3: The highest version supported by both endpoints, which is RDPUDP_PROTOCOL_VERSION_1 if either this packet or the SYN packet does not specify a version, is the version that MUST be used by both endpoints.
SendSynAndAckPacket(udpTransportMode, SynAndAck_InvalidType.None, initSequenceNumber, uUdpVer_Values.RDPUDP_PROTOCOL_VERSION_1);
}
else
{
//Section 3.1.5.1.3: The RDPUDP_SYNEX_PAYLOAD structure (section 2.2.2.9) SHOULD only be present if it is also present in the received SYN packet.
// When the
SendSynAndAckPacket(udpTransportMode, SynAndAck_InvalidType.None, initSequenceNumber,null);
}
// Expect an ACK packet or ACK and Source Packet.
RdpeudpPacket ackPacket = rdpudpSocket.ExpectACKPacket(timeout);
if (ackPacket == null)
{
this.Site.Assert.Fail("Time out when waiting for the ACK packet to response the ACK and SYN packet");
}
// Verify the ACK packet.
if (verifyPacket)
{
VerifyACKPacket(ackPacket);
}
// If the packet is an ACK and Source Packet, add the source packet to the un-processed packet.
if (ackPacket.fecHeader.uFlags.HasFlag(RDPUDP_FLAG.RDPUDP_FLAG_DATA))
{
byte[] bytes = PduMarshaler.Marshal(ackPacket, false);
RdpeudpBasePacket stackpacket = new RdpeudpBasePacket(bytes);
rdpudpSocket.ReceivePacket(stackpacket);
}
rdpudpSocket.Connected = true;
return rdpudpSocket;
}
/// <summary>
/// Create RDPUDP_SYNDATAEX_PAYLOAD Structure
/// </summary>
/// <returns></returns>
public RDPUDP_SYNDATAEX_PAYLOAD CreateSynExData(uUdpVer_Values version)
{
RDPUDP_SYNDATAEX_PAYLOAD SynExData = new RDPUDP_SYNDATAEX_PAYLOAD();
SynExData.uSynExFlags = uSynExFlags_Values.RDPUDP_VERSION_INFO_VALID;
//The uUdpVer field MUST be set to the highest RDP-UDP protocol version supported by both endpoints
if((version & uUdpVer_Values.RDPUDP_PROTOCOL_VERSION_2) != 0)
{
SynExData.uUdpVer = uUdpVer_Values.RDPUDP_PROTOCOL_VERSION_2;
}
else
{
SynExData.uUdpVer = uUdpVer_Values.RDPUDP_PROTOCOL_VERSION_1;
}
return SynExData;
}
/// <summary>
/// Send SYN and ACK packet.
/// </summary>
/// <param name="udpTransportMode">Transport mode: Reliable or Lossy</param>
/// <param name="invalidType">invalid type</param>
public void SendSynAndAckPacket(TransportMode udpTransportMode, SynAndAck_InvalidType invalidType, uint? initSequenceNumber = null, uUdpVer_Values? uUdpVer= null)
{
RdpeudpServerSocket rdpeudpSocket = rdpeudpSocketR;
if (udpTransportMode == TransportMode.Lossy)
{
rdpeudpSocket = rdpeudpSocketL;
}
if (invalidType == SynAndAck_InvalidType.None)
{
// If invalid type is None, send the packet directly.
rdpeudpSocket.SendSynAndAckPacket(initSequenceNumber,uUdpVer);
return;
}
// Create the SYN and ACK packet first.
RdpeudpPacket SynAndAckPacket = CreateInvalidSynAndACKPacket(udpTransportMode, invalidType, initSequenceNumber);
rdpeudpSocket.SendPacket(SynAndAckPacket);
}