public BCEngine()
 {
     _blockCipher = new AesEngine();
     _encoding    = Encoding.UTF8;
     pkcs         = new Pkcs7Padding();
     _padding     = pkcs;
 }
Esempio n. 2
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        /// <summary>
        /// Encapsulates the specified links into a CCF container.
        /// </summary>
        /// <param name="name">The name of the package.</param>
        /// <param name="links">The links.</param>
        /// <returns>
        /// CCF container.
        /// </returns>
        public static byte[] CreateCCF(string name, string[] links)
        {
            var sb = new StringBuilder();

            sb.Append("<?xml version=\"1.0\" encoding=\"utf-8\"?>");
            sb.Append("<CryptLoad>");
            sb.Append("<Package service=\"\" name=\"" + name + "\" url=\"Directlinks\">");

            foreach (var link in links)
            {
                sb.Append("<Download Url=\"" + link + "\">");
                sb.Append("<Url>" + link + "</Url>");
                //sb.Append("<FileName></FileName>");
                //sb.Append("<FileSize></FileSize>");
                sb.Append("</Download>");
            }

            sb.Append("</Package>");
            sb.Append("</CryptLoad>");

            var aes = new AesEngine();
            var cbc = new CbcBlockCipher(aes);
            var pk7 = new Pkcs7Padding();
            var pad = new PaddedBufferedBlockCipher(cbc, pk7);

            pad.Init(true, new ParametersWithIV(new KeyParameter(CCFKey), CCFIV));

            return(pad.DoFinal(Encoding.UTF8.GetBytes(sb.ToString())));
        }
Esempio n. 3
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        internal static string AESDecryption(string cipher, string key, string salt, Pkcs7Padding padding)
        {
            BCEngine bcEngine = new BCEngine(new AesEngine(), Encoding.UTF8);

            bcEngine.SetPadding(padding);
            return(bcEngine.Decrypt(cipher, key));
        }
Esempio n. 4
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        public BCEngine(IBlockCipher blockCipher, Encoding encoding)
        {
            _blockCipher = blockCipher;
            //_encoding = encoding;

            _encoding = Encoding.ASCII;
            Pkcs7Padding pkcs = new Pkcs7Padding();

            _padding = pkcs;
        }
Esempio n. 5
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        public AesCbcCryptor(byte[] key, byte[] iv)
        {
            KeyParameter keyParam = new KeyParameter(key);

            this._parametersWithIv = new ParametersWithIV(keyParam, iv, 0, iv.Length);
            AesEngine           engine      = new AesEngine();
            CbcBlockCipher      blockCipher = new CbcBlockCipher(engine);
            IBlockCipherPadding padding     = new Pkcs7Padding();

            this._cipher = new BufferedBlockCipher(blockCipher);
            this._cipher.Init(false, this._parametersWithIv);
        }
        public string Decrypt(ProtectedMemory key, string message)
        {
            Blake2bProtectedCryptoProvider blake2b = new Blake2bProtectedCryptoProvider();

            using ProtectedMemory paddedKey = blake2b.ComputeHashProtected(key, 64);
            ExtractHeader(message, paddedKey, out byte[] iv, out byte[] buffer);
            using (ProtectedMemory aesKey = DeriveAesKey(paddedKey))
            {
                AesState aesState = new AesState(aesKey, iv);
                aesState.AesCbcDecryptBuffer(ref buffer);
            }
            int contentLength = Pkcs7Padding.GetContentLength(buffer, 16);

            return(Encoding.UTF8.GetString(buffer, 0, contentLength));
        }
Esempio n. 7
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        /*
         * No idea... doesnt work.. cant seem to fix it..
         * Lets not pretend i know what this does...
         *
         */
        private static BufferedBlockCipher SetupBlockCipher(byte[] sharedKey, byte[] ivData, bool forEncryption)
        {
            // Setup cipher parameters with key and IV.
            var keyParam = new KeyParameter(sharedKey);
            var param    = new ParametersWithIV(keyParam, ivData);

            // Setup AES cipher in CBC mode with PKCS7 padding.
            var padding = new Pkcs7Padding();

            BufferedBlockCipher cipher = new PaddedBufferedBlockCipher(new CbcBlockCipher(new AesEngine()), padding);

            cipher.Reset();
            cipher.Init(forEncryption, param);
            return(cipher);
        }
Esempio n. 8
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        public override void PerformTest()
        {
            SecureRandom rand = new SecureRandom(new byte[20]);

            rand.SetSeed(DateTime.Now.Ticks);

            doTestPadding(new Pkcs7Padding(), rand,
                          Hex.Decode("ffffff0505050505"),
                          Hex.Decode("0000000004040404"));

            Pkcs7Padding padder = new Pkcs7Padding();

            try
            {
                padder.PadCount(new byte[8]);

                Fail("invalid padding not detected");
            }
            catch (InvalidCipherTextException e)
            {
                if (!"pad block corrupted".Equals(e.Message))
                {
                    Fail("wrong exception for corrupt padding: " + e);
                }
            }

            doTestPadding(new ISO10126d2Padding(), rand,
                          null,
                          null);

            doTestPadding(new X923Padding(), rand,
                          null,
                          null);

            doTestPadding(new TbcPadding(), rand,
                          Hex.Decode("ffffff0000000000"),
                          Hex.Decode("00000000ffffffff"));

            doTestPadding(new ZeroBytePadding(), rand,
                          Hex.Decode("ffffff0000000000"),
                          null);

            doTestPadding(new ISO7816d4Padding(), rand,
                          Hex.Decode("ffffff8000000000"),
                          Hex.Decode("0000000080000000"));
        }
Esempio n. 9
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        public static byte[] DecryptByteArray(byte[] key, byte[] iv, byte[] encryptedData)
        {
            AesEngine                 engine         = new AesEngine();
            CbcBlockCipher            blockCipher    = new CbcBlockCipher(engine); //CBC
            IBlockCipherPadding       padding        = new Pkcs7Padding();
            PaddedBufferedBlockCipher cipher         = new PaddedBufferedBlockCipher(blockCipher, padding);
            KeyParameter              keyParam       = new KeyParameter(key);
            ParametersWithIV          keyParamWithIV = new ParametersWithIV(keyParam, iv, 0, iv.Length);

            //Decrypt
            cipher.Init(false, keyParamWithIV);
            byte[] comparisonBytes = new byte[cipher.GetOutputSize(encryptedData.Length)];
            int    length          = cipher.ProcessBytes(encryptedData, comparisonBytes, 0);

            cipher.DoFinal(comparisonBytes, length); //Do the final block
            return(comparisonBytes);
        }
        public ProtectedMemory DecryptProtected(ProtectedMemory key, string message)
        {
            Blake2bProtectedCryptoProvider blake2b = new Blake2bProtectedCryptoProvider();

            using ProtectedMemory paddedKey = blake2b.ComputeHashProtected(key, 64);
            ExtractHeader(message, paddedKey, out byte[] iv, out byte[] messageBytes);
            using ProtectedMemory protectedBuffer = ProtectedMemory.Allocate(messageBytes.Length);
            protectedBuffer.Write(messageBytes, 0, messageBytes.Length);
            using (ProtectedMemory aesKey = DeriveAesKey(paddedKey))
            {
                AesState aesState = new AesState(aesKey, iv);
                aesState.AesCbcDecryptBuffer(protectedBuffer);
            }
            int             contentLength = Pkcs7Padding.GetContentLength(protectedBuffer, 16);
            ProtectedMemory result        = ProtectedMemory.Allocate(contentLength);

            protectedBuffer.CopyTo(0, result, 0, contentLength);
            return(result);
        }
Esempio n. 11
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        static PaddedBufferedBlockCipher MakeCipher(CipherMode cipher, CipherPadding padding)
        {
            var                 engine       = new T();
            IBlockCipher        blockCipher  = null;
            IBlockCipherPadding blockPadding = null;

            switch (cipher)
            {
            case CipherMode.CBC:
                blockCipher = new CbcBlockCipher(engine);
                break;
            }

            switch (padding)
            {
            case CipherPadding.ISO10126d2:
                blockPadding = new ISO10126d2Padding();
                break;

            case CipherPadding.ISO7816d4:
                blockPadding = new ISO7816d4Padding();
                break;

            case CipherPadding.PKCS7:
                blockPadding = new Pkcs7Padding();
                break;

            case CipherPadding.TBC:
                blockPadding = new TbcPadding();
                break;

            case CipherPadding.X923:
                blockPadding = new X923Padding();
                break;

            case CipherPadding.ZeroByte:
                blockPadding = new ZeroBytePadding();
                break;
            }

            return(new PaddedBufferedBlockCipher(blockCipher, blockPadding));
        }
        /// <summary>
        /// Builds an IBlockCipherPadding
        /// </summary>
        /// <param name="padding">SymmetricBlockPadding enum, padding name</param>
        /// <returns>IBlockCipherPadding with loaded padding type, if padding is WITHCTS returns null</returns>
        private IBlockCipherPadding getPadding(SymmetricBlockPadding padding)
        {
            IBlockCipherPadding paddingCipher = null;

            switch (padding)
            {
            case SymmetricBlockPadding.NOPADDING:
                paddingCipher = null;
                break;

            case SymmetricBlockPadding.ISO7816D4PADDING:
                paddingCipher = new ISO7816d4Padding();
                break;

            case SymmetricBlockPadding.ISO10126D2PADDING:
                paddingCipher = new ISO10126d2Padding();
                break;

            case SymmetricBlockPadding.PKCS7PADDING:
                paddingCipher = new Pkcs7Padding();
                break;

            case SymmetricBlockPadding.WITHCTS:
                break;

            case SymmetricBlockPadding.X923PADDING:
                paddingCipher = new X923Padding();
                break;

            case SymmetricBlockPadding.ZEROBYTEPADDING:
                paddingCipher = new ZeroBytePadding();
                break;

            default:
                this.error.setError("SB018", "Cipher " + padding + " not recognised.");
                break;
            }
            return(paddingCipher);
        }
Esempio n. 13
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        public LoginProvider(string username, string plainTextPassword)
        {
            this.Username = username;

            // Password must be 8 bute aligned
            byte[] passwordByteArray    = Encoding.ASCII.GetBytes(plainTextPassword);
            int    paddingBytesRequired = 8 - (passwordByteArray.Length % 8);

            if (paddingBytesRequired > 0)
            {
                this.Password = new byte[passwordByteArray.Length + paddingBytesRequired];
                Buffer.BlockCopy(passwordByteArray, 0, this.Password, 0, passwordByteArray.Length);

                // Password must be padded using PKCS5Padding - BouncyCastle provides a Pkcs7Padding class
                // PKCS5Padding is identical to Pkcs7Padding, providing you only pad to exactly 8 bytes
                Pkcs7Padding passwordPadder = new Pkcs7Padding();
                passwordPadder.AddPadding(this.Password, passwordByteArray.Length);
            }
            else
            {
                this.Password = passwordByteArray;
            }
        }
Esempio n. 14
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        private static PaddedBufferedBlockCipher CreateCipher(string encryptionMode, int segmentSize)
        {
            var engine = new RC6Engine();
            var padding = new Pkcs7Padding();
            IBlockCipher cipherWithoutPadding = null;
            switch (encryptionMode)
            {
                case "ECB":
                    cipherWithoutPadding = engine;
                    break;
                case "CBC":
                    cipherWithoutPadding = new CbcBlockCipher(engine);
                    break;
                case "CFB":
                    cipherWithoutPadding = new CfbBlockCipher(engine, segmentSize);
                    break;
                case "OFB":
                    cipherWithoutPadding = new OfbBlockCipher(engine, segmentSize);
                    break;
            }

            return new PaddedBufferedBlockCipher(cipherWithoutPadding, padding);
        }
Esempio n. 15
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        private void AES_CBC_MAC_Decrypt(string alg, byte[] k)
        {
            KeyParameter key;

            int tLen;

            switch (alg)
            {
            case "A128CBC-HS256":
                tLen = 16;
                break;

            case "A192CBC-HS256":
                tLen = 24;
                break;

            case "A256CBC-HS256":
                tLen = 32;
                break;

            default:
                throw new JoseException("Internal error");
            }

            KeyParameter macKey = new KeyParameter(k, 0, tLen);

            key = new KeyParameter(k, tLen, tLen);
            bool fError = false;

            //  HMAC AAD
            //  HMAC IV
            //  HMAC ciphertext
            //  HMAC 64bit int = cbit(AAD)
            byte[] rgbAl  = new byte[8];
            byte[] rgbAad = CreateAad();

            int cbAad = rgbAad.Length * 8;

            for (int i = 7; i > 0; i--)
            {
                rgbAl[i] = (byte)(cbAad % 256);
                cbAad   /= 256;
                if (cbAad == 0)
                {
                    break;
                }
            }

            HMac hmac = new HMac(new Sha256Digest());

            byte[] resBuf = new byte[hmac.GetMacSize()];
            hmac.Init(macKey);

            hmac.BlockUpdate(rgbAad, 0, rgbAad.Length);
            hmac.BlockUpdate(_iv, 0, _iv.Length);
            hmac.BlockUpdate(_RgbEncrypted, 0, _RgbEncrypted.Length);
            hmac.BlockUpdate(rgbAl, 0, rgbAl.Length);
            hmac.DoFinal(resBuf, 0);

            if (tLen != _Tag.Length)
            {
                fError = true;
            }
            for (int i = 0; i < tLen; i++)
            {
                if (resBuf[i] != _Tag[i])
                {
                    fError = true;
                }
            }


            ICipherParameters   parms   = new ParametersWithIV(key, _iv);
            IBlockCipherPadding padding = new Pkcs7Padding();
            BufferedBlockCipher cipher  = new PaddedBufferedBlockCipher(new CbcBlockCipher(new AesEngine()), padding);

            cipher.Reset();

            cipher.Init(false, parms);

            byte[] rgbOut = new byte[cipher.GetOutputSize(_RgbEncrypted.Length)];
            int    len    = cipher.ProcessBytes(_RgbEncrypted, 0, _RgbEncrypted.Length, rgbOut, 0);

            len += cipher.DoFinal(rgbOut, len);

            payload = new byte[len];
            if (fError)
            {
                throw new JoseException("Does not validate");
            }
            Array.Copy(rgbOut, payload, len);
        }
Esempio n. 16
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        public static IBufferedCipher GetCipher(string algorithm)
        {
            //IL_0008: Unknown result type (might be due to invalid IL or missing references)
            //IL_0469: Unknown result type (might be due to invalid IL or missing references)
            //IL_0495: Unknown result type (might be due to invalid IL or missing references)
            //IL_07f1: Unknown result type (might be due to invalid IL or missing references)
            if (algorithm == null)
            {
                throw new ArgumentNullException("algorithm");
            }
            algorithm = Platform.ToUpperInvariant(algorithm);
            string text = (string)algorithms.get_Item((object)algorithm);

            if (text != null)
            {
                algorithm = text;
            }
            IBasicAgreement basicAgreement = null;

            if (algorithm == "IES")
            {
                basicAgreement = new DHBasicAgreement();
            }
            else if (algorithm == "ECIES")
            {
                basicAgreement = new ECDHBasicAgreement();
            }
            if (basicAgreement != null)
            {
                return(new BufferedIesCipher(new IesEngine(basicAgreement, new Kdf2BytesGenerator(new Sha1Digest()), new HMac(new Sha1Digest()))));
            }
            if (Platform.StartsWith(algorithm, "PBE"))
            {
                if (Platform.EndsWith(algorithm, "-CBC"))
                {
                    if (algorithm == "PBEWITHSHA1ANDDES-CBC")
                    {
                        return(new PaddedBufferedBlockCipher(new CbcBlockCipher(new DesEngine())));
                    }
                    if (algorithm == "PBEWITHSHA1ANDRC2-CBC")
                    {
                        return(new PaddedBufferedBlockCipher(new CbcBlockCipher(new RC2Engine())));
                    }
                    if (Strings.IsOneOf(algorithm, "PBEWITHSHAAND2-KEYTRIPLEDES-CBC", "PBEWITHSHAAND3-KEYTRIPLEDES-CBC"))
                    {
                        return(new PaddedBufferedBlockCipher(new CbcBlockCipher(new DesEdeEngine())));
                    }
                    if (Strings.IsOneOf(algorithm, "PBEWITHSHAAND128BITRC2-CBC", "PBEWITHSHAAND40BITRC2-CBC"))
                    {
                        return(new PaddedBufferedBlockCipher(new CbcBlockCipher(new RC2Engine())));
                    }
                }
                else if ((Platform.EndsWith(algorithm, "-BC") || Platform.EndsWith(algorithm, "-OPENSSL")) && Strings.IsOneOf(algorithm, "PBEWITHSHAAND128BITAES-CBC-BC", "PBEWITHSHAAND192BITAES-CBC-BC", "PBEWITHSHAAND256BITAES-CBC-BC", "PBEWITHSHA256AND128BITAES-CBC-BC", "PBEWITHSHA256AND192BITAES-CBC-BC", "PBEWITHSHA256AND256BITAES-CBC-BC", "PBEWITHMD5AND128BITAES-CBC-OPENSSL", "PBEWITHMD5AND192BITAES-CBC-OPENSSL", "PBEWITHMD5AND256BITAES-CBC-OPENSSL"))
                {
                    return(new PaddedBufferedBlockCipher(new CbcBlockCipher(new AesFastEngine())));
                }
            }
            string[] array = algorithm.Split(new char[1] {
                '/'
            });
            IBlockCipher           blockCipher           = null;
            IAsymmetricBlockCipher asymmetricBlockCipher = null;
            IStreamCipher          streamCipher          = null;
            string text2 = array[0];
            string text3 = (string)algorithms.get_Item((object)text2);

            if (text3 != null)
            {
                text2 = text3;
            }
            CipherAlgorithm cipherAlgorithm;

            try
            {
                cipherAlgorithm = (CipherAlgorithm)Enums.GetEnumValue(typeof(CipherAlgorithm), text2);
            }
            catch (ArgumentException)
            {
                throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
            }
            switch (cipherAlgorithm)
            {
            case CipherAlgorithm.AES:
                blockCipher = new AesFastEngine();
                break;

            case CipherAlgorithm.ARC4:
                streamCipher = new RC4Engine();
                break;

            case CipherAlgorithm.BLOWFISH:
                blockCipher = new BlowfishEngine();
                break;

            case CipherAlgorithm.CAMELLIA:
                blockCipher = new CamelliaEngine();
                break;

            case CipherAlgorithm.CAST5:
                blockCipher = new Cast5Engine();
                break;

            case CipherAlgorithm.CAST6:
                blockCipher = new Cast6Engine();
                break;

            case CipherAlgorithm.DES:
                blockCipher = new DesEngine();
                break;

            case CipherAlgorithm.DESEDE:
                blockCipher = new DesEdeEngine();
                break;

            case CipherAlgorithm.ELGAMAL:
                asymmetricBlockCipher = new ElGamalEngine();
                break;

            case CipherAlgorithm.GOST28147:
                blockCipher = new Gost28147Engine();
                break;

            case CipherAlgorithm.HC128:
                streamCipher = new HC128Engine();
                break;

            case CipherAlgorithm.HC256:
                streamCipher = new HC256Engine();
                break;

            case CipherAlgorithm.IDEA:
                blockCipher = new IdeaEngine();
                break;

            case CipherAlgorithm.NOEKEON:
                blockCipher = new NoekeonEngine();
                break;

            case CipherAlgorithm.PBEWITHSHAAND128BITRC4:
            case CipherAlgorithm.PBEWITHSHAAND40BITRC4:
                streamCipher = new RC4Engine();
                break;

            case CipherAlgorithm.RC2:
                blockCipher = new RC2Engine();
                break;

            case CipherAlgorithm.RC5:
                blockCipher = new RC532Engine();
                break;

            case CipherAlgorithm.RC5_64:
                blockCipher = new RC564Engine();
                break;

            case CipherAlgorithm.RC6:
                blockCipher = new RC6Engine();
                break;

            case CipherAlgorithm.RIJNDAEL:
                blockCipher = new RijndaelEngine();
                break;

            case CipherAlgorithm.RSA:
                asymmetricBlockCipher = new RsaBlindedEngine();
                break;

            case CipherAlgorithm.SALSA20:
                streamCipher = new Salsa20Engine();
                break;

            case CipherAlgorithm.SEED:
                blockCipher = new SeedEngine();
                break;

            case CipherAlgorithm.SERPENT:
                blockCipher = new SerpentEngine();
                break;

            case CipherAlgorithm.SKIPJACK:
                blockCipher = new SkipjackEngine();
                break;

            case CipherAlgorithm.TEA:
                blockCipher = new TeaEngine();
                break;

            case CipherAlgorithm.THREEFISH_256:
                blockCipher = new ThreefishEngine(256);
                break;

            case CipherAlgorithm.THREEFISH_512:
                blockCipher = new ThreefishEngine(512);
                break;

            case CipherAlgorithm.THREEFISH_1024:
                blockCipher = new ThreefishEngine(1024);
                break;

            case CipherAlgorithm.TNEPRES:
                blockCipher = new TnepresEngine();
                break;

            case CipherAlgorithm.TWOFISH:
                blockCipher = new TwofishEngine();
                break;

            case CipherAlgorithm.VMPC:
                streamCipher = new VmpcEngine();
                break;

            case CipherAlgorithm.VMPC_KSA3:
                streamCipher = new VmpcKsa3Engine();
                break;

            case CipherAlgorithm.XTEA:
                blockCipher = new XteaEngine();
                break;

            default:
                throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
            }
            if (streamCipher != null)
            {
                if (array.Length > 1)
                {
                    throw new ArgumentException("Modes and paddings not used for stream ciphers");
                }
                return(new BufferedStreamCipher(streamCipher));
            }
            bool flag  = false;
            bool flag2 = true;
            IBlockCipherPadding blockCipherPadding = null;
            IAeadBlockCipher    aeadBlockCipher    = null;

            if (array.Length > 2)
            {
                if (streamCipher != null)
                {
                    throw new ArgumentException("Paddings not used for stream ciphers");
                }
                string        text4 = array[2];
                CipherPadding cipherPadding;
                if (text4 == "")
                {
                    cipherPadding = CipherPadding.RAW;
                }
                else if (text4 == "X9.23PADDING")
                {
                    cipherPadding = CipherPadding.X923PADDING;
                }
                else
                {
                    try
                    {
                        cipherPadding = (CipherPadding)Enums.GetEnumValue(typeof(CipherPadding), text4);
                    }
                    catch (ArgumentException)
                    {
                        throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
                    }
                }
                switch (cipherPadding)
                {
                case CipherPadding.NOPADDING:
                    flag2 = false;
                    break;

                case CipherPadding.ISO10126PADDING:
                case CipherPadding.ISO10126D2PADDING:
                case CipherPadding.ISO10126_2PADDING:
                    blockCipherPadding = new ISO10126d2Padding();
                    break;

                case CipherPadding.ISO7816_4PADDING:
                case CipherPadding.ISO9797_1PADDING:
                    blockCipherPadding = new ISO7816d4Padding();
                    break;

                case CipherPadding.ISO9796_1:
                case CipherPadding.ISO9796_1PADDING:
                    asymmetricBlockCipher = new ISO9796d1Encoding(asymmetricBlockCipher);
                    break;

                case CipherPadding.OAEP:
                case CipherPadding.OAEPPADDING:
                    asymmetricBlockCipher = new OaepEncoding(asymmetricBlockCipher);
                    break;

                case CipherPadding.OAEPWITHMD5ANDMGF1PADDING:
                    asymmetricBlockCipher = new OaepEncoding(asymmetricBlockCipher, new MD5Digest());
                    break;

                case CipherPadding.OAEPWITHSHA1ANDMGF1PADDING:
                case CipherPadding.OAEPWITHSHA_1ANDMGF1PADDING:
                    asymmetricBlockCipher = new OaepEncoding(asymmetricBlockCipher, new Sha1Digest());
                    break;

                case CipherPadding.OAEPWITHSHA224ANDMGF1PADDING:
                case CipherPadding.OAEPWITHSHA_224ANDMGF1PADDING:
                    asymmetricBlockCipher = new OaepEncoding(asymmetricBlockCipher, new Sha224Digest());
                    break;

                case CipherPadding.OAEPWITHSHA256ANDMGF1PADDING:
                case CipherPadding.OAEPWITHSHA_256ANDMGF1PADDING:
                    asymmetricBlockCipher = new OaepEncoding(asymmetricBlockCipher, new Sha256Digest());
                    break;

                case CipherPadding.OAEPWITHSHA384ANDMGF1PADDING:
                case CipherPadding.OAEPWITHSHA_384ANDMGF1PADDING:
                    asymmetricBlockCipher = new OaepEncoding(asymmetricBlockCipher, new Sha384Digest());
                    break;

                case CipherPadding.OAEPWITHSHA512ANDMGF1PADDING:
                case CipherPadding.OAEPWITHSHA_512ANDMGF1PADDING:
                    asymmetricBlockCipher = new OaepEncoding(asymmetricBlockCipher, new Sha512Digest());
                    break;

                case CipherPadding.PKCS1:
                case CipherPadding.PKCS1PADDING:
                    asymmetricBlockCipher = new Pkcs1Encoding(asymmetricBlockCipher);
                    break;

                case CipherPadding.PKCS5:
                case CipherPadding.PKCS5PADDING:
                case CipherPadding.PKCS7:
                case CipherPadding.PKCS7PADDING:
                    blockCipherPadding = new Pkcs7Padding();
                    break;

                case CipherPadding.TBCPADDING:
                    blockCipherPadding = new TbcPadding();
                    break;

                case CipherPadding.WITHCTS:
                    flag = true;
                    break;

                case CipherPadding.X923PADDING:
                    blockCipherPadding = new X923Padding();
                    break;

                case CipherPadding.ZEROBYTEPADDING:
                    blockCipherPadding = new ZeroBytePadding();
                    break;

                default:
                    throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");

                case CipherPadding.RAW:
                    break;
                }
            }
            string text5 = "";

            if (array.Length > 1)
            {
                text5 = array[1];
                int    digitIndex = GetDigitIndex(text5);
                string text6      = ((digitIndex >= 0) ? text5.Substring(0, digitIndex) : text5);
                try
                {
                    switch ((text6 == "") ? CipherMode.NONE : ((CipherMode)Enums.GetEnumValue(typeof(CipherMode), text6)))
                    {
                    case CipherMode.CBC:
                        blockCipher = new CbcBlockCipher(blockCipher);
                        break;

                    case CipherMode.CCM:
                        aeadBlockCipher = new CcmBlockCipher(blockCipher);
                        break;

                    case CipherMode.CFB:
                    {
                        int bitBlockSize = ((digitIndex < 0) ? (8 * blockCipher.GetBlockSize()) : int.Parse(text5.Substring(digitIndex)));
                        blockCipher = new CfbBlockCipher(blockCipher, bitBlockSize);
                        break;
                    }

                    case CipherMode.CTR:
                        blockCipher = new SicBlockCipher(blockCipher);
                        break;

                    case CipherMode.CTS:
                        flag        = true;
                        blockCipher = new CbcBlockCipher(blockCipher);
                        break;

                    case CipherMode.EAX:
                        aeadBlockCipher = new EaxBlockCipher(blockCipher);
                        break;

                    case CipherMode.GCM:
                        aeadBlockCipher = new GcmBlockCipher(blockCipher);
                        break;

                    case CipherMode.GOFB:
                        blockCipher = new GOfbBlockCipher(blockCipher);
                        break;

                    case CipherMode.OCB:
                        aeadBlockCipher = new OcbBlockCipher(blockCipher, CreateBlockCipher(cipherAlgorithm));
                        break;

                    case CipherMode.OFB:
                    {
                        int blockSize = ((digitIndex < 0) ? (8 * blockCipher.GetBlockSize()) : int.Parse(text5.Substring(digitIndex)));
                        blockCipher = new OfbBlockCipher(blockCipher, blockSize);
                        break;
                    }

                    case CipherMode.OPENPGPCFB:
                        blockCipher = new OpenPgpCfbBlockCipher(blockCipher);
                        break;

                    case CipherMode.SIC:
                        if (blockCipher.GetBlockSize() < 16)
                        {
                            throw new ArgumentException("Warning: SIC-Mode can become a twotime-pad if the blocksize of the cipher is too small. Use a cipher with a block size of at least 128 bits (e.g. AES)");
                        }
                        blockCipher = new SicBlockCipher(blockCipher);
                        break;

                    default:
                        throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");

                    case CipherMode.ECB:
                    case CipherMode.NONE:
                        break;
                    }
                }
                catch (ArgumentException)
                {
                    throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
                }
            }
            if (aeadBlockCipher != null)
            {
                if (flag)
                {
                    throw new SecurityUtilityException("CTS mode not valid for AEAD ciphers.");
                }
                if (flag2 && array.Length > 2 && array[2] != "")
                {
                    throw new SecurityUtilityException("Bad padding specified for AEAD cipher.");
                }
                return(new BufferedAeadBlockCipher(aeadBlockCipher));
            }
            if (blockCipher != null)
            {
                if (flag)
                {
                    return(new CtsBlockCipher(blockCipher));
                }
                if (blockCipherPadding != null)
                {
                    return(new PaddedBufferedBlockCipher(blockCipher, blockCipherPadding));
                }
                if (!flag2 || blockCipher.IsPartialBlockOkay)
                {
                    return(new BufferedBlockCipher(blockCipher));
                }
                return(new PaddedBufferedBlockCipher(blockCipher));
            }
            if (asymmetricBlockCipher != null)
            {
                return(new BufferedAsymmetricBlockCipher(asymmetricBlockCipher));
            }
            throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
        }
Esempio n. 17
0
        public static IBufferedCipher GetCipher(
            string algorithm)
        {
            if (algorithm == null)
            {
                throw new ArgumentNullException("algorithm");
            }

            algorithm = Platform.ToUpperInvariant(algorithm);

            {
                string aliased = (string)algorithms[algorithm];

                if (aliased != null)
                {
                    algorithm = aliased;
                }
            }

            IBasicAgreement iesAgreement = null;

            if (algorithm == "IES")
            {
                iesAgreement = new DHBasicAgreement();
            }
            else if (algorithm == "ECIES")
            {
                iesAgreement = new ECDHBasicAgreement();
            }

            if (iesAgreement != null)
            {
                return(new BufferedIesCipher(
                           new IesEngine(
                               iesAgreement,
                               new Kdf2BytesGenerator(
                                   new Sha1Digest()),
                               new HMac(
                                   new Sha1Digest()))));
            }



            if (Platform.StartsWith(algorithm, "PBE"))
            {
                if (Platform.EndsWith(algorithm, "-CBC"))
                {
                    if (algorithm == "PBEWITHSHA1ANDDES-CBC")
                    {
                        return(new PaddedBufferedBlockCipher(
                                   new CbcBlockCipher(new DesEngine())));
                    }
                    else if (algorithm == "PBEWITHSHA1ANDRC2-CBC")
                    {
                        return(new PaddedBufferedBlockCipher(
                                   new CbcBlockCipher(new RC2Engine())));
                    }
                    else if (Strings.IsOneOf(algorithm,
                                             "PBEWITHSHAAND2-KEYTRIPLEDES-CBC", "PBEWITHSHAAND3-KEYTRIPLEDES-CBC"))
                    {
                        return(new PaddedBufferedBlockCipher(
                                   new CbcBlockCipher(new DesEdeEngine())));
                    }
                    else if (Strings.IsOneOf(algorithm,
                                             "PBEWITHSHAAND128BITRC2-CBC", "PBEWITHSHAAND40BITRC2-CBC"))
                    {
                        return(new PaddedBufferedBlockCipher(
                                   new CbcBlockCipher(new RC2Engine())));
                    }
                }
                else if (Platform.EndsWith(algorithm, "-BC") || Platform.EndsWith(algorithm, "-OPENSSL"))
                {
                    if (Strings.IsOneOf(algorithm,
                                        "PBEWITHSHAAND128BITAES-CBC-BC",
                                        "PBEWITHSHAAND192BITAES-CBC-BC",
                                        "PBEWITHSHAAND256BITAES-CBC-BC",
                                        "PBEWITHSHA256AND128BITAES-CBC-BC",
                                        "PBEWITHSHA256AND192BITAES-CBC-BC",
                                        "PBEWITHSHA256AND256BITAES-CBC-BC",
                                        "PBEWITHMD5AND128BITAES-CBC-OPENSSL",
                                        "PBEWITHMD5AND192BITAES-CBC-OPENSSL",
                                        "PBEWITHMD5AND256BITAES-CBC-OPENSSL"))
                    {
                        return(new PaddedBufferedBlockCipher(
                                   new CbcBlockCipher(new AesFastEngine())));
                    }
                }
            }



            string[] parts = algorithm.Split('/');

            IBlockCipher           blockCipher     = null;
            IAsymmetricBlockCipher asymBlockCipher = null;
            IStreamCipher          streamCipher    = null;

            string algorithmName = parts[0];

            {
                string aliased = (string)algorithms[algorithmName];

                if (aliased != null)
                {
                    algorithmName = aliased;
                }
            }

            CipherAlgorithm cipherAlgorithm;

            try
            {
                cipherAlgorithm = (CipherAlgorithm)Enums.GetEnumValue(typeof(CipherAlgorithm), algorithmName);
            }
            catch (ArgumentException)
            {
                throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
            }

            switch (cipherAlgorithm)
            {
            case CipherAlgorithm.AES:
                blockCipher = new AesFastEngine();
                break;

            case CipherAlgorithm.ARC4:
                streamCipher = new RC4Engine();
                break;

            case CipherAlgorithm.BLOWFISH:
                blockCipher = new BlowfishEngine();
                break;

            case CipherAlgorithm.CAMELLIA:
                blockCipher = new CamelliaEngine();
                break;

            case CipherAlgorithm.CAST5:
                blockCipher = new Cast5Engine();
                break;

            case CipherAlgorithm.CAST6:
                blockCipher = new Cast6Engine();
                break;

            case CipherAlgorithm.DES:
                blockCipher = new DesEngine();
                break;

            case CipherAlgorithm.DESEDE:
                blockCipher = new DesEdeEngine();
                break;

            case CipherAlgorithm.ELGAMAL:
                asymBlockCipher = new ElGamalEngine();
                break;

            case CipherAlgorithm.GOST28147:
                blockCipher = new Gost28147Engine();
                break;

            case CipherAlgorithm.HC128:
                streamCipher = new HC128Engine();
                break;

            case CipherAlgorithm.HC256:
                streamCipher = new HC256Engine();
                break;

            case CipherAlgorithm.IDEA:
                blockCipher = new IdeaEngine();
                break;

            case CipherAlgorithm.NOEKEON:
                blockCipher = new NoekeonEngine();
                break;

            case CipherAlgorithm.PBEWITHSHAAND128BITRC4:
            case CipherAlgorithm.PBEWITHSHAAND40BITRC4:
                streamCipher = new RC4Engine();
                break;

            case CipherAlgorithm.RC2:
                blockCipher = new RC2Engine();
                break;

            case CipherAlgorithm.RC5:
                blockCipher = new RC532Engine();
                break;

            case CipherAlgorithm.RC5_64:
                blockCipher = new RC564Engine();
                break;

            case CipherAlgorithm.RC6:
                blockCipher = new RC6Engine();
                break;

            case CipherAlgorithm.RIJNDAEL:
                blockCipher = new RijndaelEngine();
                break;

            case CipherAlgorithm.RSA:
                asymBlockCipher = new RsaBlindedEngine();
                break;

            case CipherAlgorithm.SALSA20:
                streamCipher = new Salsa20Engine();
                break;

            case CipherAlgorithm.SEED:
                blockCipher = new SeedEngine();
                break;

            case CipherAlgorithm.SERPENT:
                blockCipher = new SerpentEngine();
                break;

            case CipherAlgorithm.SKIPJACK:
                blockCipher = new SkipjackEngine();
                break;

            case CipherAlgorithm.TEA:
                blockCipher = new TeaEngine();
                break;

            case CipherAlgorithm.THREEFISH_256:
                blockCipher = new ThreefishEngine(ThreefishEngine.BLOCKSIZE_256);
                break;

            case CipherAlgorithm.THREEFISH_512:
                blockCipher = new ThreefishEngine(ThreefishEngine.BLOCKSIZE_512);
                break;

            case CipherAlgorithm.THREEFISH_1024:
                blockCipher = new ThreefishEngine(ThreefishEngine.BLOCKSIZE_1024);
                break;

            case CipherAlgorithm.TNEPRES:
                blockCipher = new TnepresEngine();
                break;

            case CipherAlgorithm.TWOFISH:
                blockCipher = new TwofishEngine();
                break;

            case CipherAlgorithm.VMPC:
                streamCipher = new VmpcEngine();
                break;

            case CipherAlgorithm.VMPC_KSA3:
                streamCipher = new VmpcKsa3Engine();
                break;

            case CipherAlgorithm.XTEA:
                blockCipher = new XteaEngine();
                break;

            default:
                throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
            }

            if (streamCipher != null)
            {
                if (parts.Length > 1)
                {
                    throw new ArgumentException("Modes and paddings not used for stream ciphers");
                }

                return(new BufferedStreamCipher(streamCipher));
            }


            bool cts    = false;
            bool padded = true;
            IBlockCipherPadding padding         = null;
            IAeadBlockCipher    aeadBlockCipher = null;

            if (parts.Length > 2)
            {
                if (streamCipher != null)
                {
                    throw new ArgumentException("Paddings not used for stream ciphers");
                }

                string paddingName = parts[2];

                CipherPadding cipherPadding;
                if (paddingName == "")
                {
                    cipherPadding = CipherPadding.RAW;
                }
                else if (paddingName == "X9.23PADDING")
                {
                    cipherPadding = CipherPadding.X923PADDING;
                }
                else
                {
                    try
                    {
                        cipherPadding = (CipherPadding)Enums.GetEnumValue(typeof(CipherPadding), paddingName);
                    }
                    catch (ArgumentException)
                    {
                        throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
                    }
                }

                switch (cipherPadding)
                {
                case CipherPadding.NOPADDING:
                    padded = false;
                    break;

                case CipherPadding.RAW:
                    break;

                case CipherPadding.ISO10126PADDING:
                case CipherPadding.ISO10126D2PADDING:
                case CipherPadding.ISO10126_2PADDING:
                    padding = new ISO10126d2Padding();
                    break;

                case CipherPadding.ISO7816_4PADDING:
                case CipherPadding.ISO9797_1PADDING:
                    padding = new ISO7816d4Padding();
                    break;

                case CipherPadding.ISO9796_1:
                case CipherPadding.ISO9796_1PADDING:
                    asymBlockCipher = new ISO9796d1Encoding(asymBlockCipher);
                    break;

                case CipherPadding.OAEP:
                case CipherPadding.OAEPPADDING:
                    asymBlockCipher = new OaepEncoding(asymBlockCipher);
                    break;

                case CipherPadding.OAEPWITHMD5ANDMGF1PADDING:
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new MD5Digest());
                    break;

                case CipherPadding.OAEPWITHSHA1ANDMGF1PADDING:
                case CipherPadding.OAEPWITHSHA_1ANDMGF1PADDING:
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha1Digest());
                    break;

                case CipherPadding.OAEPWITHSHA224ANDMGF1PADDING:
                case CipherPadding.OAEPWITHSHA_224ANDMGF1PADDING:
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha224Digest());
                    break;

                case CipherPadding.OAEPWITHSHA256ANDMGF1PADDING:
                case CipherPadding.OAEPWITHSHA_256ANDMGF1PADDING:
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha256Digest());
                    break;

                case CipherPadding.OAEPWITHSHA384ANDMGF1PADDING:
                case CipherPadding.OAEPWITHSHA_384ANDMGF1PADDING:
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha384Digest());
                    break;

                case CipherPadding.OAEPWITHSHA512ANDMGF1PADDING:
                case CipherPadding.OAEPWITHSHA_512ANDMGF1PADDING:
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha512Digest());
                    break;

                case CipherPadding.PKCS1:
                case CipherPadding.PKCS1PADDING:
                    asymBlockCipher = new Pkcs1Encoding(asymBlockCipher);
                    break;

                case CipherPadding.PKCS5:
                case CipherPadding.PKCS5PADDING:
                case CipherPadding.PKCS7:
                case CipherPadding.PKCS7PADDING:
                    padding = new Pkcs7Padding();
                    break;

                case CipherPadding.TBCPADDING:
                    padding = new TbcPadding();
                    break;

                case CipherPadding.WITHCTS:
                    cts = true;
                    break;

                case CipherPadding.X923PADDING:
                    padding = new X923Padding();
                    break;

                case CipherPadding.ZEROBYTEPADDING:
                    padding = new ZeroBytePadding();
                    break;

                default:
                    throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
                }
            }

            string mode = "";

            if (parts.Length > 1)
            {
                mode = parts[1];

                int    di       = GetDigitIndex(mode);
                string modeName = di >= 0 ? mode.Substring(0, di) : mode;

                try
                {
                    CipherMode cipherMode = modeName == ""
                        ? CipherMode.NONE
                        : (CipherMode)Enums.GetEnumValue(typeof(CipherMode), modeName);

                    switch (cipherMode)
                    {
                    case CipherMode.ECB:
                    case CipherMode.NONE:
                        break;

                    case CipherMode.CBC:
                        blockCipher = new CbcBlockCipher(blockCipher);
                        break;

                    case CipherMode.CCM:
                        aeadBlockCipher = new CcmBlockCipher(blockCipher);
                        break;

                    case CipherMode.CFB:
                    {
                        int bits = (di < 0)
                                ?       8 * blockCipher.GetBlockSize()
                                :       int.Parse(mode.Substring(di));

                        blockCipher = new CfbBlockCipher(blockCipher, bits);
                        break;
                    }

                    case CipherMode.CTR:
                        blockCipher = new SicBlockCipher(blockCipher);
                        break;

                    case CipherMode.CTS:
                        cts         = true;
                        blockCipher = new CbcBlockCipher(blockCipher);
                        break;

                    case CipherMode.EAX:
                        aeadBlockCipher = new EaxBlockCipher(blockCipher);
                        break;

                    case CipherMode.GCM:
                        aeadBlockCipher = new GcmBlockCipher(blockCipher);
                        break;

                    case CipherMode.GOFB:
                        blockCipher = new GOfbBlockCipher(blockCipher);
                        break;

                    case CipherMode.OCB:
                        aeadBlockCipher = new OcbBlockCipher(blockCipher, CreateBlockCipher(cipherAlgorithm));
                        break;

                    case CipherMode.OFB:
                    {
                        int bits = (di < 0)
                                ?       8 * blockCipher.GetBlockSize()
                                :       int.Parse(mode.Substring(di));

                        blockCipher = new OfbBlockCipher(blockCipher, bits);
                        break;
                    }

                    case CipherMode.OPENPGPCFB:
                        blockCipher = new OpenPgpCfbBlockCipher(blockCipher);
                        break;

                    case CipherMode.SIC:
                        if (blockCipher.GetBlockSize() < 16)
                        {
                            throw new ArgumentException("Warning: SIC-Mode can become a twotime-pad if the blocksize of the cipher is too small. Use a cipher with a block size of at least 128 bits (e.g. AES)");
                        }
                        blockCipher = new SicBlockCipher(blockCipher);
                        break;

                    default:
                        throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
                    }
                }
                catch (ArgumentException)
                {
                    throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
                }
            }

            if (aeadBlockCipher != null)
            {
                if (cts)
                {
                    throw new SecurityUtilityException("CTS mode not valid for AEAD ciphers.");
                }
                if (padded && parts.Length > 2 && parts[2] != "")
                {
                    throw new SecurityUtilityException("Bad padding specified for AEAD cipher.");
                }

                return(new BufferedAeadBlockCipher(aeadBlockCipher));
            }

            if (blockCipher != null)
            {
                if (cts)
                {
                    return(new CtsBlockCipher(blockCipher));
                }

                if (padding != null)
                {
                    return(new PaddedBufferedBlockCipher(blockCipher, padding));
                }

                if (!padded || blockCipher.IsPartialBlockOkay)
                {
                    return(new BufferedBlockCipher(blockCipher));
                }

                return(new PaddedBufferedBlockCipher(blockCipher));
            }

            if (asymBlockCipher != null)
            {
                return(new BufferedAsymmetricBlockCipher(asymBlockCipher));
            }

            throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
        }
Esempio n. 18
0
        public static IBufferedCipher GetCipher(
            string algorithm)
        {
            if (algorithm == null)
            {
                throw new ArgumentNullException("algorithm");
            }

            algorithm = algorithm.ToUpper(CultureInfo.InvariantCulture);

            string aliased = (string)algorithms[algorithm];

            if (aliased != null)
            {
                algorithm = aliased;
            }



            IBasicAgreement iesAgreement = null;

            if (algorithm == "IES")
            {
                iesAgreement = new DHBasicAgreement();
            }
            else if (algorithm == "ECIES")
            {
                iesAgreement = new ECDHBasicAgreement();
            }

            if (iesAgreement != null)
            {
                return(new BufferedIesCipher(
                           new IesEngine(
                               iesAgreement,
                               new Kdf2BytesGenerator(
                                   new Sha1Digest()),
                               new HMac(
                                   new Sha1Digest()))));
            }



            if (algorithm.StartsWith("PBE"))
            {
                switch (algorithm)
                {
                case "PBEWITHSHAAND2-KEYTRIPLEDES-CBC":
                case "PBEWITHSHAAND3-KEYTRIPLEDES-CBC":
                    return(new PaddedBufferedBlockCipher(
                               new CbcBlockCipher(new DesEdeEngine())));

                case "PBEWITHSHAAND128BITRC2-CBC":
                case "PBEWITHSHAAND40BITRC2-CBC":
                    return(new PaddedBufferedBlockCipher(
                               new CbcBlockCipher(new RC2Engine())));

                case "PBEWITHSHAAND128BITAES-CBC-BC":
                case "PBEWITHSHAAND192BITAES-CBC-BC":
                case "PBEWITHSHAAND256BITAES-CBC-BC":
                case "PBEWITHSHA256AND128BITAES-CBC-BC":
                case "PBEWITHSHA256AND192BITAES-CBC-BC":
                case "PBEWITHSHA256AND256BITAES-CBC-BC":
                case "PBEWITHMD5AND128BITAES-CBC-OPENSSL":
                case "PBEWITHMD5AND192BITAES-CBC-OPENSSL":
                case "PBEWITHMD5AND256BITAES-CBC-OPENSSL":
                    return(new PaddedBufferedBlockCipher(
                               new CbcBlockCipher(new AesFastEngine())));

                case "PBEWITHSHA1ANDDES-CBC":
                    return(new PaddedBufferedBlockCipher(
                               new CbcBlockCipher(new DesEngine())));

                case "PBEWITHSHA1ANDRC2-CBC":
                    return(new PaddedBufferedBlockCipher(
                               new CbcBlockCipher(new RC2Engine())));
                }
            }



            string[] parts = algorithm.Split('/');

            IBlockCipher           blockCipher     = null;
            IAsymmetricBlockCipher asymBlockCipher = null;
            IStreamCipher          streamCipher    = null;

            switch (parts[0])
            {
            case "AES":
                blockCipher = new AesFastEngine();
                break;

            case "ARC4":
                streamCipher = new RC4Engine();
                break;

            case "BLOWFISH":
                blockCipher = new BlowfishEngine();
                break;

            case "CAMELLIA":
                blockCipher = new CamelliaEngine();
                break;

            case "CAST5":
                blockCipher = new Cast5Engine();
                break;

            case "CAST6":
                blockCipher = new Cast6Engine();
                break;

            case "DES":
                blockCipher = new DesEngine();
                break;

            case "DESEDE":
                blockCipher = new DesEdeEngine();
                break;

            case "ELGAMAL":
                asymBlockCipher = new ElGamalEngine();
                break;

            case "GOST28147":
                blockCipher = new Gost28147Engine();
                break;

            case "HC128":
                streamCipher = new HC128Engine();
                break;

            case "HC256":
                streamCipher = new HC256Engine();
                break;

#if INCLUDE_IDEA
            case "IDEA":
                blockCipher = new IdeaEngine();
                break;
#endif
            case "NOEKEON":
                blockCipher = new NoekeonEngine();
                break;

            case "PBEWITHSHAAND128BITRC4":
            case "PBEWITHSHAAND40BITRC4":
                streamCipher = new RC4Engine();
                break;

            case "RC2":
                blockCipher = new RC2Engine();
                break;

            case "RC5":
                blockCipher = new RC532Engine();
                break;

            case "RC5-64":
                blockCipher = new RC564Engine();
                break;

            case "RC6":
                blockCipher = new RC6Engine();
                break;

            case "RIJNDAEL":
                blockCipher = new RijndaelEngine();
                break;

            case "RSA":
                asymBlockCipher = new RsaBlindedEngine();
                break;

            case "SALSA20":
                streamCipher = new Salsa20Engine();
                break;

            case "SEED":
                blockCipher = new SeedEngine();
                break;

            case "SERPENT":
                blockCipher = new SerpentEngine();
                break;

            case "SKIPJACK":
                blockCipher = new SkipjackEngine();
                break;

            case "TEA":
                blockCipher = new TeaEngine();
                break;

            case "TWOFISH":
                blockCipher = new TwofishEngine();
                break;

            case "VMPC":
                streamCipher = new VmpcEngine();
                break;

            case "VMPC-KSA3":
                streamCipher = new VmpcKsa3Engine();
                break;

            case "XTEA":
                blockCipher = new XteaEngine();
                break;

            default:
                throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
            }

            if (streamCipher != null)
            {
                if (parts.Length > 1)
                {
                    throw new ArgumentException("Modes and paddings not used for stream ciphers");
                }

                return(new BufferedStreamCipher(streamCipher));
            }


            bool cts    = false;
            bool padded = true;
            IBlockCipherPadding padding         = null;
            IAeadBlockCipher    aeadBlockCipher = null;

            if (parts.Length > 2)
            {
                if (streamCipher != null)
                {
                    throw new ArgumentException("Paddings not used for stream ciphers");
                }

                switch (parts[2])
                {
                case "NOPADDING":
                    padded = false;
                    break;

                case "":
                case "RAW":
                    break;

                case "ISO10126PADDING":
                case "ISO10126D2PADDING":
                case "ISO10126-2PADDING":
                    padding = new ISO10126d2Padding();
                    break;

                case "ISO7816-4PADDING":
                case "ISO9797-1PADDING":
                    padding = new ISO7816d4Padding();
                    break;

                case "ISO9796-1":
                case "ISO9796-1PADDING":
                    asymBlockCipher = new ISO9796d1Encoding(asymBlockCipher);
                    break;

                case "OAEP":
                case "OAEPPADDING":
                    asymBlockCipher = new OaepEncoding(asymBlockCipher);
                    break;

                case "OAEPWITHMD5ANDMGF1PADDING":
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new MD5Digest());
                    break;

                case "OAEPWITHSHA1ANDMGF1PADDING":
                case "OAEPWITHSHA-1ANDMGF1PADDING":
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha1Digest());
                    break;

                case "OAEPWITHSHA224ANDMGF1PADDING":
                case "OAEPWITHSHA-224ANDMGF1PADDING":
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha224Digest());
                    break;

                case "OAEPWITHSHA256ANDMGF1PADDING":
                case "OAEPWITHSHA-256ANDMGF1PADDING":
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha256Digest());
                    break;

                case "OAEPWITHSHA384ANDMGF1PADDING":
                case "OAEPWITHSHA-384ANDMGF1PADDING":
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha384Digest());
                    break;

                case "OAEPWITHSHA512ANDMGF1PADDING":
                case "OAEPWITHSHA-512ANDMGF1PADDING":
                    asymBlockCipher = new OaepEncoding(asymBlockCipher, new Sha512Digest());
                    break;

                case "PKCS1":
                case "PKCS1PADDING":
                    asymBlockCipher = new Pkcs1Encoding(asymBlockCipher);
                    break;

                case "PKCS5":
                case "PKCS5PADDING":
                case "PKCS7":
                case "PKCS7PADDING":
                    padding = new Pkcs7Padding();
                    break;

                case "TBCPADDING":
                    padding = new TbcPadding();
                    break;

                case "WITHCTS":
                    cts = true;
                    break;

                case "X9.23PADDING":
                case "X923PADDING":
                    padding = new X923Padding();
                    break;

                case "ZEROBYTEPADDING":
                    padding = new ZeroBytePadding();
                    break;

                default:
                    throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
                }
            }

            string mode = "";
            if (parts.Length > 1)
            {
                mode = parts[1];

                int    di       = GetDigitIndex(mode);
                string modeName = di >= 0 ? mode.Substring(0, di) : mode;

                switch (modeName)
                {
                case "":
                case "ECB":
                case "NONE":
                    break;

                case "CBC":
                    blockCipher = new CbcBlockCipher(blockCipher);
                    break;

                case "CCM":
                    aeadBlockCipher = new CcmBlockCipher(blockCipher);
                    break;

                case "CFB":
                {
                    int bits = (di < 0)
                                                        ?       8 * blockCipher.GetBlockSize()
                                                        :       int.Parse(mode.Substring(di));

                    blockCipher = new CfbBlockCipher(blockCipher, bits);
                    break;
                }

                case "CTR":
                    blockCipher = new SicBlockCipher(blockCipher);
                    break;

                case "CTS":
                    cts         = true;
                    blockCipher = new CbcBlockCipher(blockCipher);
                    break;

                case "EAX":
                    aeadBlockCipher = new EaxBlockCipher(blockCipher);
                    break;

                case "GCM":
                    aeadBlockCipher = new GcmBlockCipher(blockCipher);
                    break;

                case "GOFB":
                    blockCipher = new GOfbBlockCipher(blockCipher);
                    break;

                case "OFB":
                {
                    int bits = (di < 0)
                                                        ?       8 * blockCipher.GetBlockSize()
                                                        :       int.Parse(mode.Substring(di));

                    blockCipher = new OfbBlockCipher(blockCipher, bits);
                    break;
                }

                case "OPENPGPCFB":
                    blockCipher = new OpenPgpCfbBlockCipher(blockCipher);
                    break;

                case "SIC":
                    if (blockCipher.GetBlockSize() < 16)
                    {
                        throw new ArgumentException("Warning: SIC-Mode can become a twotime-pad if the blocksize of the cipher is too small. Use a cipher with a block size of at least 128 bits (e.g. AES)");
                    }
                    blockCipher = new SicBlockCipher(blockCipher);
                    break;

                default:
                    throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
                }
            }

            if (aeadBlockCipher != null)
            {
                if (cts)
                {
                    throw new SecurityUtilityException("CTS mode not valid for AEAD ciphers.");
                }
                if (padded && parts.Length > 2 && parts[2] != "")
                {
                    throw new SecurityUtilityException("Bad padding specified for AEAD cipher.");
                }

                return(new BufferedAeadBlockCipher(aeadBlockCipher));
            }

            if (blockCipher != null)
            {
                if (cts)
                {
                    return(new CtsBlockCipher(blockCipher));
                }

                if (padding != null)
                {
                    return(new PaddedBufferedBlockCipher(blockCipher, padding));
                }

                if (!padded || blockCipher.IsPartialBlockOkay)
                {
                    return(new BufferedBlockCipher(blockCipher));
                }

                return(new PaddedBufferedBlockCipher(blockCipher));
            }

            if (asymBlockCipher != null)
            {
                return(new BufferedAsymmetricBlockCipher(asymBlockCipher));
            }

            throw new SecurityUtilityException("Cipher " + algorithm + " not recognised.");
        }