Renci.SshNet.Security.Cryptography.Ciphers.AesCipher.GenerateWorkingKey C# (CSharp) Méthode

        private uint[] GenerateWorkingKey(bool isEncryption, byte[] key)
        {
            int KC = key.Length / 4;  // key length in words

            if (((KC != 4) && (KC != 6) && (KC != 8)) || ((KC * 4) != key.Length))
                throw new ArgumentException("Key length not 128/192/256 bits.");

            _rounds = KC + 6;  // This is not always true for the generalized Rijndael that allows larger block sizes
            uint[] W = new uint[(_rounds + 1) *  4];   // 4 words in a block

            //
            // copy the key into the round key array
            //

            int t = 0;

            for (int i = 0; i < key.Length; t++)
            {
                W[(t >> 2) * 4 + (t & 3)] = LittleEndianToUInt32(key, i);
                i += 4;
            }

            //
            // while not enough round key material calculated
            // calculate new values
            //
            int k = (_rounds + 1) << 2;
            for (int i = KC; (i < k); i++)
            {
                uint temp = W[((i - 1) >> 2) * 4 + ((i - 1) & 3)];
                if ((i % KC) == 0)
                {
                    temp = SubWord(Shift(temp, 8)) ^ rcon[(i / KC) - 1];
                }
                else if ((KC > 6) && ((i % KC) == 4))
                {
                    temp = SubWord(temp);
                }

                W[(i >> 2) * 4 + (i & 3)] = W[((i - KC) >> 2) * 4 + ((i - KC) & 3)] ^ temp;
            }

            if (!isEncryption)
            {
                for (int j = 1; j < _rounds; j++)
                {
                    for (int i = 0; i < 4; i++)
                    {
                        W[j * 4 + i] = InvMcol(W[j * 4 + i]);
                    }
                }
            }

            return W;
        }