protected static int ReadInteger(RdpPacket packet)
{
if (packet.ReadByte() != 2)
{
throw new Exception("Data Error!");
}
int num2 = packet.ReadByte();
byte[] buffer = new byte[4];
switch (num2)
{
case 4:
packet.Read(buffer, 0, 4);
return(BitConverter.ToInt32(buffer, 0));
case 3:
packet.Read(buffer, 0, 3);
return(BitConverter.ToInt32(buffer, 0));
case 2:
packet.Read(buffer, 0, 2);
return(BitConverter.ToInt32(buffer, 0));
}
packet.Read(buffer, 0, 1);
return(BitConverter.ToInt32(buffer, 0));
}
/// <summary>
/// Server X.224 Connection Confirm PDU
/// </summary>
private static int receiveConnectNegotiation()
{
RdpPacket packet = ISO.Receive();
packet.Position += 7L;
if (packet.Position >= packet.Length)
{
return(0);
}
switch (packet.ReadByte())
{
// TYPE_RDP_NEG_RSP
case 0x02:
Options.serverNegotiateFlags = (NegotiationFlags)packet.ReadByte();
packet.ReadLittleEndian16();
return(packet.ReadLittleEndian32());
// TYPE_RDP_NEG_FAILURE
case 0x03:
packet.ReadByte();
packet.ReadLittleEndian16();
switch ((NegotiationFailureCodes)packet.ReadLittleEndian32())
{
case NegotiationFailureCodes.SSL_REQUIRED_BY_SERVER:
throw new RDFatalException("The server requires that the client support Enhanced RDP Security with TLS 1.0");
case NegotiationFailureCodes.SSL_NOT_ALLOWED_BY_SERVER:
return(0x10000000);
case NegotiationFailureCodes.SSL_CERT_NOT_ON_SERVER:
throw new RDFatalException("The server does not possess a valid authentication certificate and cannot initialize the External Security Protocol Provider");
case NegotiationFailureCodes.INCONSISTENT_FLAGS:
throw new RDFatalException("The list of requested security protocols is not consistent with the current security protocol in effect.");
case NegotiationFailureCodes.HYBRID_REQUIRED_BY_SERVER:
throw new RDFatalException("The server requires that the client support Enhanced RDP Security with CredSSP");
case NegotiationFailureCodes.SSL_WITH_USER_AUTH_REQUIRED_BY_SERVER:
throw new RDFatalException("The server requires that the client support Enhanced RDP Security and certificate-based client authentication");
}
throw new RDFatalException("Unknown Negotiation failure!");
}
throw new RDFatalException("Negotiation failed, requested security level not supported by server.");
}
protected static int ReadTag(RdpPacket packet, string Identifier)
{
int num = packet.ReadByte();
ReadLength(packet, Identifier);
return(num);
}
protected static int ReadTag(RdpPacket packet, int ExpectedTag, string Identifier)
{
int num = packet.ReadByte();
if (num != ExpectedTag)
{
throw new Exception(string.Concat(new object[] { "Expected DER tag ", ExpectedTag, " but got ", num }));
}
return(ReadLength(packet, Identifier));
}
internal static RdpPacket Receive()
{
byte[] buffer = new byte[0x3000];
int count = Network.Receive(buffer);
RdpPacket packet = new RdpPacket();
packet.Write(buffer, 0, count);
packet.Position = 0L;
int num2 = 0;
if (packet.ReadByte() == 3)
{
packet.ReadByte();
num2 = packet.ReadBigEndian16();
long position = packet.Position;
while (num2 > count)
{
int num4 = Network.Receive(buffer);
packet.Position = count;
packet.Write(buffer, 0, num4);
count += num4;
}
packet.Position = position;
return(packet);
}
num2 = packet.ReadByte();
if ((num2 & 0x80) != 0)
{
num2 &= -129;
num2 = num2 << (8 + packet.ReadByte());
}
return(packet);
}
protected static int ReadLength(RdpPacket packet, string Identifier)
{
int num;
byte[] buffer = new byte[4];
int num2 = packet.ReadByte();
switch (num2)
{
case 0x84:
buffer[3] = (byte)packet.ReadByte();
buffer[2] = (byte)packet.ReadByte();
buffer[1] = (byte)packet.ReadByte();
buffer[0] = (byte)packet.ReadByte();
num = BitConverter.ToInt32(buffer, 0);
break;
case 0x83:
buffer[2] = (byte)packet.ReadByte();
buffer[1] = (byte)packet.ReadByte();
buffer[0] = (byte)packet.ReadByte();
num = BitConverter.ToInt32(buffer, 0);
break;
case 130:
buffer[1] = (byte)packet.ReadByte();
buffer[0] = (byte)packet.ReadByte();
num = BitConverter.ToInt32(buffer, 0);
break;
case 0x81:
num = packet.ReadByte();
break;
default:
num = num2;
break;
}
m_Fixup.Add(Identifier, new Fixup(Identifier, packet.Position, num));
return(num);
}
