void Decode(byte[] message, int startIndex, int length)
{
int payloadOffset = length;
int micOffset = 64;
ValidateArguments(message, startIndex, length);
if (message.Length >= 64)
{
Flags = (NtlmFlags)BitConverterLE.ToUInt32(message, startIndex + 60);
}
else
{
Flags = (NtlmFlags)0x8201;
}
int lmLength = BitConverterLE.ToUInt16(message, startIndex + 12);
int lmOffset = BitConverterLE.ToUInt16(message, startIndex + 16);
LmChallengeResponse = new byte[lmLength];
Buffer.BlockCopy(message, startIndex + lmOffset, LmChallengeResponse, 0, lmLength);
payloadOffset = Math.Min(payloadOffset, lmOffset);
int ntLength = BitConverterLE.ToUInt16(message, startIndex + 20);
int ntOffset = BitConverterLE.ToUInt16(message, startIndex + 24);
NtChallengeResponse = new byte[ntLength];
Buffer.BlockCopy(message, startIndex + ntOffset, NtChallengeResponse, 0, ntLength);
payloadOffset = Math.Min(payloadOffset, ntOffset);
int domainLength = BitConverterLE.ToUInt16(message, startIndex + 28);
int domainOffset = BitConverterLE.ToUInt16(message, startIndex + 32);
Domain = DecodeString(message, startIndex + domainOffset, domainLength);
payloadOffset = Math.Min(payloadOffset, domainOffset);
int userLength = BitConverterLE.ToUInt16(message, startIndex + 36);
int userOffset = BitConverterLE.ToUInt16(message, startIndex + 40);
UserName = DecodeString(message, startIndex + userOffset, userLength);
payloadOffset = Math.Min(payloadOffset, userOffset);
int workstationLength = BitConverterLE.ToUInt16(message, startIndex + 44);
int workstationOffset = BitConverterLE.ToUInt16(message, startIndex + 48);
Workstation = DecodeString(message, startIndex + workstationOffset, workstationLength);
payloadOffset = Math.Min(payloadOffset, workstationOffset);
int skeyLength = BitConverterLE.ToUInt16(message, startIndex + 52);
int skeyOffset = BitConverterLE.ToUInt16(message, startIndex + 56);
EncryptedRandomSessionKey = new byte[skeyLength];
Buffer.BlockCopy(message, startIndex + skeyOffset, EncryptedRandomSessionKey, 0, skeyLength);
payloadOffset = Math.Min(payloadOffset, skeyOffset);
// OSVersion
if ((Flags & NtlmFlags.NegotiateVersion) != 0 && length >= 72)
{
// decode the OS Version
int major = message[startIndex + 64];
int minor = message[startIndex + 65];
int build = BitConverterLE.ToUInt16(message, startIndex + 66);
OSVersion = new Version(major, minor, build);
micOffset += 8;
}
// MIC
if (micOffset + 16 <= payloadOffset)
{
Mic = new byte[16];
Buffer.BlockCopy(message, startIndex + micOffset, Mic, 0, Mic.Length);
}
}