Esempio n. 1
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        /// <summary>
        /// Creates a new PassphrasePrng from a passphrase and salt,
        /// and seeds it with the output of PKCS5
        /// </summary>
        ///
        /// <param name="Digest">Digest engine</param>
        /// <param name="Passphrase">The passphrase</param>
        /// <param name="Salt">The salt value</param>
        /// <param name="Iterations">The number of transformation iterations performed by the digest with PKCS5 (default is 10,000)</param>
        /// <param name="DisposeEngine">Dispose of digest engine when <see cref="Dispose()"/> on this class is called (default is true)</param>
        ///
        /// <exception cref="CryptoRandomException">Thrown if a null Digest, Passphrase or Salt are used</exception>
        public PBPRng(IDigest Digest, byte[] Passphrase, byte[] Salt, int Iterations = PKCS_ITERATIONS, bool DisposeEngine = true)
        {
            if (Digest == null)
            {
                throw new CryptoRandomException("PBPRng:Ctor", "Digest can not be null!", new ArgumentNullException());
            }
            if (Passphrase == null)
            {
                throw new CryptoRandomException("PBPRng:Ctor", "Passphrase can not be null!", new ArgumentNullException());
            }
            if (Salt == null)
            {
                throw new CryptoRandomException("PBPRng:Ctor", "Salt can not be null!", new ArgumentNullException());
            }

            try
            {
                _disposeEngine = DisposeEngine;
                PKCS5 pkcs = new PKCS5(Digest, Iterations, false);
                _digest = Digest;
                pkcs.Initialize(Salt, Passphrase);
                _rndData = new byte[_digest.BlockSize];
                pkcs.Generate(_rndData);
            }
            catch (Exception e)
            {
                throw new Exception(e.Message);
            }

            _position = 0;
        }