The CryptSignAndEncryptMessage function creates a hash of the specified content, signs the hash, encrypts the content, hashes the encrypted contents and the signed hash, and then encodes both the encrypted content and the signed hash. The result is the same as if the hash were first signed and then encrypted.

static extern bool CryptSignAndEncryptMessage(

Declare Function CryptSignAndEncryptMessage Lib "crypt32.dll" (TODO) As TODO

Documentation

[CryptSignAndEncryptMessage] on MSDN http://msdn.microsoft.com/en-us/library/windows/desktop/aa380278%28v=vs.85%29.aspx

secur32

3: EncryptMessage

public static extern int EncryptMessage(ref SECURITY_HANDLE phContext, uint fQOP, //managed ulong == 64 bit

Declare Function EncryptMessage Lib "secur32.dll" (TODO) As TODO

Documentation

[EncryptMessage] on MSDN

4: InitializeSecurityContext

public static extern int EncryptMessage(ref SECURITY_HANDLE phContext,

public void EncryptMessage(byte[] message,bool bUseClientContext,out byte[] encryptedBuffer)

if(EncryptMessage(ref EncryptionContext,0,ref DescBuffer,0) != SEC_E_OK)

throw new Exception("EncryptMessage() failed!!!");

MyHelper.EncryptMessage(Message,true,out EncryptedBuffer);

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