DoFinal() public method

public DoFinal ( byte output, int outOff ) : int
output byte
outOff int
return int
Example #1
0
        public static IDStorage decryptKeyStoreStorage(byte[] c_baKey, byte[] c_baIV, string c_sBase64JsonStorage)
        {
            const int MacBitSize = 128;
            byte [] baPayload = new byte[0];

            var decryptCipher = new GcmBlockCipher(new AesFastEngine());
            var parameters = new AeadParameters(new KeyParameter(c_baKey), MacBitSize, c_baIV, baPayload);
            decryptCipher.Init (false, parameters);

            byte[] baEncryptedStorage = Convert.FromBase64String (c_sBase64JsonStorage);

            var decryptedText = new byte[decryptCipher.GetOutputSize(baEncryptedStorage.Length)];
            try
            {
                var len = decryptCipher.ProcessBytes(baEncryptedStorage, 0, baEncryptedStorage.Length, decryptedText, 0);
                decryptCipher.DoFinal(decryptedText, len);
            }
            catch (InvalidCipherTextException)
            {
                //Return null if it doesn't authenticate
                return null;
            }

            string sJsonStorage = Encoding.GetEncoding (1252).GetString (decryptedText);
            IDStorage _KeyStoreStorage = JsonConvert.DeserializeObject <IDStorage> (sJsonStorage);

            return _KeyStoreStorage;
        }
Example #2
0
        public byte[] Encrypt(byte[] plain, byte[] key, byte[] iv, byte[] aad = null, byte[] associated = null)
        {
            if (key.Length * 8 != this.KeySize)
            {
                throw new InvalidOperationException($"the given key has invalid size {key.Length * 8}, expect {this.KeySize}");
            }

            var cipher = new Modes.GcmBlockCipher(new Engines.AesEngine());

            cipher.Init(true, new Parameters.AeadParameters(new Parameters.KeyParameter(key), this.MacSize, iv, associated));

            if (aad != null)
            {
                cipher.ProcessAadBytes(aad, 0, aad.Length);
            }

            var ret = new byte[cipher.GetOutputSize(plain.Length)];
            var len = cipher.ProcessBytes(plain, 0, plain.Length, ret, 0);

            cipher.DoFinal(ret, len);

            return(ret);
        }
Example #3
0
		private void randomTest(
			SecureRandom	srng,
			IGcmMultiplier	m)
		{
			int kLength = 16 + 8 * srng.Next(3);
			byte[] K = new byte[kLength];
			srng.NextBytes(K);

			int pLength = srng.Next(1024);
			byte[] P = new byte[pLength];
			srng.NextBytes(P);

			int aLength = srng.Next(1024);
			byte[] A = new byte[aLength];
			srng.NextBytes(A);

			int ivLength = 1 + srng.Next(1024);
			byte[] IV = new byte[ivLength];
			srng.NextBytes(IV);

			GcmBlockCipher cipher = new GcmBlockCipher(new AesFastEngine(), m);
			AeadParameters parameters = new AeadParameters(new KeyParameter(K), 16 * 8, IV, A);
			cipher.Init(true, parameters);
			byte[] C = new byte[cipher.GetOutputSize(P.Length)];
			int len = cipher.ProcessBytes(P, 0, P.Length, C, 0);
			len += cipher.DoFinal(C, len);

			if (C.Length != len)
			{
//				Console.WriteLine("" + C.Length + "/" + len);
				Fail("encryption reported incorrect length in randomised test");
			}

			byte[] encT = cipher.GetMac();
			byte[] tail = new byte[C.Length - P.Length];
			Array.Copy(C, P.Length, tail, 0, tail.Length);

			if (!AreEqual(encT, tail))
			{
				Fail("stream contained wrong mac in randomised test");
			}

			cipher.Init(false, parameters);
			byte[] decP = new byte[cipher.GetOutputSize(C.Length)];
			len = cipher.ProcessBytes(C, 0, C.Length, decP, 0);
			len += cipher.DoFinal(decP, len);

			if (!AreEqual(P, decP))
			{
				Fail("incorrect decrypt in randomised test");
			}

			byte[] decT = cipher.GetMac();
			if (!AreEqual(encT, decT))
			{
				Fail("decryption produced different mac from encryption");
			}
		}
Example #4
0
		private void checkTestCase(
			GcmBlockCipher	encCipher,
			GcmBlockCipher	decCipher,
			string			testName,
			byte[]			P,
			byte[]			C,
			byte[]			T)
		{
			byte[] enc = new byte[encCipher.GetOutputSize(P.Length)];
			int len = encCipher.ProcessBytes(P, 0, P.Length, enc, 0);
			len += encCipher.DoFinal(enc, len);

			if (enc.Length != len)
			{
//				Console.WriteLine("" + enc.Length + "/" + len);
				Fail("encryption reported incorrect length: " + testName);
			}

			byte[] mac = encCipher.GetMac();

			byte[] data = new byte[P.Length];
			Array.Copy(enc, data, data.Length);
			byte[] tail = new byte[enc.Length - P.Length];
			Array.Copy(enc, P.Length, tail, 0, tail.Length);

			if (!AreEqual(C, data))
			{
				Fail("incorrect encrypt in: " + testName);
			}

			if (!AreEqual(T, mac))
			{
				Fail("GetMac() returned wrong mac in: " + testName);
			}

			if (!AreEqual(T, tail))
			{
				Fail("stream contained wrong mac in: " + testName);
			}

			byte[] dec = new byte[decCipher.GetOutputSize(enc.Length)];
			len = decCipher.ProcessBytes(enc, 0, enc.Length, dec, 0);
			len += decCipher.DoFinal(dec, len);
			mac = decCipher.GetMac();

			data = new byte[C.Length];
			Array.Copy(dec, data, data.Length);

			if (!AreEqual(P, data))
			{
				Fail("incorrect decrypt in: " + testName);
			}
		}
Example #5
0
		/// <summary>
		/// Simple Decryption & Authentication (AES-GCM) of a UTF8 Message
		/// </summary>
		/// <param name="encryptedMessage">The encrypted message.</param>
		/// <param name="key">The key.</param>
		/// <param name="nonSecretPayloadLength">Length of the optional non-secret payload.</param>
		/// <returns>Decrypted Message</returns>
		public static byte[] SimpleDecrypt(byte[] encryptedMessage, byte[] key, int nonSecretPayloadLength = 0)
		{
			//User Error Checks
			if (key == null || key.Length != KeyBitSize / 8)
				throw new ArgumentException(String.Format("Key needs to be {0} bit!", KeyBitSize), "key");

			if (encryptedMessage == null || encryptedMessage.Length == 0)
				throw new ArgumentException("Encrypted Message Required!", "encryptedMessage");

			using (var cipherStream = new MemoryStream(encryptedMessage))
			using (var cipherReader = new BinaryReader(cipherStream))
			{
				//Grab Payload
				var nonSecretPayload = cipherReader.ReadBytes(nonSecretPayloadLength);

				//Grab Nonce
				var nonce = cipherReader.ReadBytes(NonceBitSize / 8);

				var cipher = new GcmBlockCipher(new AesFastEngine());
				var parameters = new AeadParameters(new KeyParameter(key), MacBitSize, nonce, nonSecretPayload);
				cipher.Init(false, parameters);

				//Decrypt Cipher Text
				var cipherText = cipherReader.ReadBytes(encryptedMessage.Length - nonSecretPayloadLength - nonce.Length);
				var plainText = new byte[cipher.GetOutputSize(cipherText.Length)];

				try
				{
					var len = cipher.ProcessBytes(cipherText, 0, cipherText.Length, plainText, 0);
					cipher.DoFinal(plainText, len);

				}
				catch (InvalidCipherTextException)
				{
					//Return null if it doesn't authenticate
					return null;
				}

				return plainText;
			}

		}
Example #6
0
		/// <summary>
		/// Simple Encryption And Authentication (AES-GCM) of a UTF8 string.
		/// </summary>
		/// <param name="secretMessage">The secret message.</param>
		/// <param name="key">The key.</param>
		/// <param name="nonSecretPayload">Optional non-secret payload.</param>
		/// <returns>Encrypted Message</returns>
		/// <remarks>
		/// Adds overhead of (Optional-Payload + BlockSize(16) + Message +  HMac-Tag(16)) * 1.33 Base64
		/// </remarks>
		public static byte[] SimpleEncrypt(byte[] secretMessage, byte[] key, byte[] nonSecretPayload = null)
		{
			//User Error Checks
			if (key == null || key.Length != KeyBitSize / 8)
				throw new ArgumentException(String.Format("Key needs to be {0} bit!", KeyBitSize), "key");

			if (secretMessage == null || secretMessage.Length == 0)
				throw new ArgumentException("Secret Message Required!", "secretMessage");

			//Non-secret Payload Optional
			nonSecretPayload = nonSecretPayload ?? new byte[] { };

			//Using random nonce large enough not to repeat
			var nonce = new byte[NonceBitSize / 8];
			Random.NextBytes(nonce, 0, nonce.Length);

			var cipher = new GcmBlockCipher(new AesFastEngine());
			var parameters = new AeadParameters(new KeyParameter(key), MacBitSize, nonce, nonSecretPayload);
			cipher.Init(true, parameters);

			//Generate Cipher Text With Auth Tag
			var cipherText = new byte[cipher.GetOutputSize(secretMessage.Length)];
			var len = cipher.ProcessBytes(secretMessage, 0, secretMessage.Length, cipherText, 0);
			cipher.DoFinal(cipherText, len);

			//Assemble Message
			using (var combinedStream = new MemoryStream())
			{
				using (var binaryWriter = new BinaryWriter(combinedStream))
				{
					//Prepend Authenticated Payload
					binaryWriter.Write(nonSecretPayload);
					//Prepend Nonce
					binaryWriter.Write(nonce);
					//Write Cipher Text
					binaryWriter.Write(cipherText);
				}
				return combinedStream.ToArray();
			}
		}
Example #7
0
        // AES
        private String decrypt(byte[] data, byte[] key, byte[] iv)
        {
            var cipher = new GcmBlockCipher(new AesFastEngine());
            var parameters = new ParametersWithIV(new KeyParameter(key, 0, 32), iv);

            cipher.Init(false, parameters);
            var pText = new byte[cipher.GetOutputSize(data.Length)];
            var len2 = cipher.ProcessBytes(data, 0, data.Length, pText, 0);
            cipher.DoFinal(pText, len2);

            return System.Text.Encoding.Default.GetString(pText);
        }
		protected override int Decrypt (DisposeContext d, ContentType contentType, IBufferOffsetSize input, IBufferOffsetSize output)
		{
			var implicitNonce = IsClient ? ServerWriteIV : ClientWriteIV;
			var writeKey = IsClient ? ServerWriteKey : ClientWriteKey;

			#if DEBUG_FULL
			if (Cipher.EnableDebugging) {
				DebugHelper.WriteLine ("FIXED IV", implicitNonce);
				DebugHelper.WriteLine ("WRITE KEY", writeKey);
				DebugHelper.WriteLine ("SEQUENCE: {0}", ReadSequenceNumber);
			}
			#endif

			var length = input.Size - ExplicitNonceSize;

			var aad = new TlsBuffer (13);
			aad.Write (ReadSequenceNumber);
			aad.Write ((byte)contentType);
			aad.Write ((short)Protocol);
			aad.Write ((short)(length - MacSize));

			#if DEBUG_FULL
			if (Cipher.EnableDebugging)
				DebugHelper.WriteFull ("TAG", aad);
			#endif

			var gcm = new GcmBlockCipher (new AesEngine ());
			var key = new KeyParameter (writeKey.Buffer);

			var nonce = d.CreateBuffer (ImplicitNonceSize + ExplicitNonceSize);
			Buffer.BlockCopy (implicitNonce.Buffer, 0, nonce.Buffer, 0, ImplicitNonceSize);
			Buffer.BlockCopy (input.Buffer, input.Offset, nonce.Buffer, ImplicitNonceSize, ExplicitNonceSize);

			#if DEBUG_FULL
			if (Cipher.EnableDebugging)
				DebugHelper.WriteLine ("NONCE", nonce);
			#endif

			var parameters = new AeadParameters (key, 128, nonce.Buffer, aad.Buffer);
			gcm.Init (false, parameters);

			int ret;
			try {
				ret = gcm.ProcessBytes (input.Buffer, input.Offset + ExplicitNonceSize, length, output.Buffer, output.Offset);

				ret += gcm.DoFinal (output.Buffer, output.Offset + ret);
			} catch (CryptoException ex) {
				throw new TlsException (AlertDescription.BadRecordMAC, ex.Message);
			}

			return ret;
		}
Example #9
0
        public static string encryptIdStorage(byte[] c_baKey, byte[] c_baIV, IDStorage c_KeyStoreStorage)
        {
            const int MacBitSize = 128;
            byte [] baPayload = new byte[0];

            var encryptCipher = new GcmBlockCipher(new AesFastEngine());
            var parameters = new AeadParameters(new KeyParameter(c_baKey), MacBitSize, c_baIV, baPayload);
            encryptCipher.Init (true, parameters);

            string sJsonStorage = JsonConvert.SerializeObject (c_KeyStoreStorage);//ConvertToJSON and
            byte[] baJsonStorage = Encoding.GetEncoding(1252).GetBytes(sJsonStorage);// get Bytes from ASCII-String

            var cipherText = new byte[encryptCipher.GetOutputSize(baJsonStorage.Length)];
            var len = encryptCipher.ProcessBytes(baJsonStorage, 0, baJsonStorage.Length, cipherText, 0);
            encryptCipher.DoFinal(cipherText, len);

            string sCipherString = Convert.ToBase64String (cipherText);
            return sCipherString;
        }