public void EncryptMessage(byte[] message, out byte[] encryptedBuffer) { encryptedBuffer = null; SECURITY_HANDLE EncryptionContext = _hClientContext; SecPkgContext_Sizes ContextSizes; if (QueryContextAttributes(ref EncryptionContext, SECPKG_ATTR_SIZES, out ContextSizes) != SEC_E_OK) { throw new Exception("QueryContextAttribute() failed!!!"); } MultipleSecBufferHelper[] ThisSecHelper = new MultipleSecBufferHelper[] { new MultipleSecBufferHelper(new byte[ContextSizes.cbSecurityTrailer], SecBufferType.SECBUFFER_TOKEN), new MultipleSecBufferHelper(message, SecBufferType.SECBUFFER_DATA), new MultipleSecBufferHelper(new byte[ContextSizes.cbBlockSize], SecBufferType.SECBUFFER_PADDING) }; SecBufferDesc DescBuffer = new SecBufferDesc(ThisSecHelper); try { if (EncryptMessage(ref EncryptionContext, SECQOP_WRAP_NO_ENCRYPT, ref DescBuffer, 0) != SEC_E_OK) { throw new Exception("EncryptMessage() failed!!!"); } encryptedBuffer = DescBuffer.GetSecBufferByteArray(); } finally { DescBuffer.Dispose(); } }
public void DecryptMessage(int messageLength, byte[] encryptedBuffer, out byte[] decryptedBuffer) { decryptedBuffer = null; SECURITY_HANDLE DecryptionContext = _hClientContext; byte[] EncryptedMessage = new byte[messageLength]; Array.Copy(encryptedBuffer, 0, EncryptedMessage, 0, messageLength); int SecurityTrailerLength = encryptedBuffer.Length - messageLength; byte[] SecurityTrailer = new byte[SecurityTrailerLength]; Array.Copy(encryptedBuffer, messageLength, SecurityTrailer, 0, SecurityTrailerLength); MultipleSecBufferHelper[] ThisSecHelper = new MultipleSecBufferHelper[] { new MultipleSecBufferHelper(EncryptedMessage, SecBufferType.SECBUFFER_DATA), new MultipleSecBufferHelper(SecurityTrailer, SecBufferType.SECBUFFER_STREAM) }; SecBufferDesc DescBuffer = new SecBufferDesc(ThisSecHelper); try { uint EncryptionQuality; if (DecryptMessage(ref DecryptionContext, ref DescBuffer, 0, out EncryptionQuality) != SEC_E_OK) { throw new Exception("DecryptMessage() failed!!!"); } decryptedBuffer = new byte[messageLength]; Array.Copy(DescBuffer.GetSecBufferByteArray(), 0, decryptedBuffer, 0, messageLength); } finally { DescBuffer.Dispose(); } }
internal SecBufferDesc(MultipleSecBufferHelper[] secBufferBytesArray) { if (secBufferBytesArray == null || secBufferBytesArray.Length == 0) { throw new ArgumentException("secBufferBytesArray cannot be null or 0 length"); } ulVersion = (int)SecBufferType.SECBUFFER_VERSION; cBuffers = secBufferBytesArray.Length; //Allocate memory for SecBuffer Array.... pBuffers = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(SecBuffer)) * cBuffers); for (int Index = 0; Index < secBufferBytesArray.Length; Index++) { //Super hack: Now allocate memory for the individual SecBuffers //and just copy the bit values to the SecBuffer array!!! SecBuffer ThisSecBuffer = new SecBuffer(secBufferBytesArray[Index].Buffer, secBufferBytesArray[Index].BufferType); //We will write out bits in the following order: //int cbBuffer; //int BufferType; //pvBuffer; //Note: that we won't be releasing the memory allocated by ThisSecBuffer until we //are disposed... int CurrentOffset = Index * Marshal.SizeOf(typeof(SecBuffer)); Marshal.WriteInt32(pBuffers, CurrentOffset, ThisSecBuffer.cbBuffer); int length = CurrentOffset + Marshal.SizeOf(ThisSecBuffer.cbBuffer); Marshal.WriteInt32(pBuffers, length, ThisSecBuffer.BufferType); length = CurrentOffset + Marshal.SizeOf(ThisSecBuffer.cbBuffer) + Marshal.SizeOf(ThisSecBuffer.BufferType); Marshal.WriteIntPtr(pBuffers, length, ThisSecBuffer.pvBuffer); } }