/// <summary>
        /// Encrypt a plain text message
        /// </summary>
        /// 
        /// <param name="Input">The plain text</param>
        /// 
        /// <returns>The cipher text</returns>
        public byte[] Encrypt(byte[] Input)
        {
            if (!_isEncryption)
                throw new CryptoAsymmetricSignException("FujisakiCipher:Encrypt", "The cipher is not initialized for encryption!", new ArgumentException());

            // generate random vector r of length k bits
            GF2Vector r = new GF2Vector(_K, _rndEngine);
            // convert r to byte array
            byte[] rBytes = r.GetEncoded();
            // compute (r||input)
            byte[] rm = ByteUtils.Concatenate(rBytes, Input);

            // compute H(r||input)
            _dgtEngine.BlockUpdate(rm, 0, rm.Length);
            byte[] hrm = new byte[_dgtEngine.DigestSize];
            _dgtEngine.DoFinal(hrm, 0);
            // convert H(r||input) to error vector z
            GF2Vector z = CCA2Conversions.Encode(_N, _T, hrm);

            // compute c1 = E(r, z)
            byte[] c1 = CCA2Primitives.Encrypt((MPKCPublicKey)_asmKey, r, z).GetEncoded();
            byte[] c2;

            // get PRNG object
            using (KDF2Drbg sr0 = new KDF2Drbg(GetDigest(_cprParams.Digest)))
            {
                // seed PRNG with r'
                sr0.Initialize(rBytes);
                // generate random c2
                c2 = new byte[Input.Length];
                sr0.Generate(c2);
            }

            // XOR with input
            for (int i = 0; i < Input.Length; i++)
                c2[i] ^= Input[i];

            // return (c1||c2)
            return ByteUtils.Concatenate(c1, c2);
        }
        public byte[] Encrypt(byte[] Input)
        {
            if (!_isEncryption)
                throw new CryptoAsymmetricSignException("PointchevalCipher:Encrypt", "The cipher is not initialized for encryption!", new ArgumentException());

            int kDiv8 = _K >> 3;
            // generate random r of length k div 8 bytes
            byte[] r = new byte[kDiv8];
            _rndEngine.GetBytes(r);
            // generate random vector r' of length k bits
            GF2Vector rPrime = new GF2Vector(_K, _rndEngine);
            // convert r' to byte array
            byte[] rPrimeBytes = rPrime.GetEncoded();
            // compute (input||r)
            byte[] mr = ByteUtils.Concatenate(Input, r);
            // compute H(input||r)
            _dgtEngine.BlockUpdate(mr, 0, mr.Length);
            byte[] hmr = new byte[_dgtEngine.DigestSize];
            _dgtEngine.DoFinal(hmr, 0);

            // convert H(input||r) to error vector z
            GF2Vector z = CCA2Conversions.Encode(_N, _T, hmr);

            // compute c1 = E(rPrime, z)
            byte[] c1 = CCA2Primitives.Encrypt((MPKCPublicKey)_asmKey, rPrime, z).GetEncoded();
            byte[] c2;
            // get PRNG object
            using (KDF2Drbg sr0 = new KDF2Drbg(GetDigest(_cprParams.Digest)))
            {
                // seed PRNG with r'
                sr0.Initialize(rPrimeBytes);
                // generate random c2
                c2 = new byte[Input.Length + kDiv8];
                sr0.Generate(c2);
            }

            // XOR with input
            for (int i = 0; i < Input.Length; i++)
                c2[i] ^= Input[i];

            // XOR with r
            for (int i = 0; i < kDiv8; i++)
                c2[Input.Length + i] ^= r[i];

            // return (c1||c2)
            return ByteUtils.Concatenate(c1, c2);
        }