Builderdash.LoadFromPemFileClass.DecodeRsaPrivateKey C# (CSharp) Method

        private static RSACryptoServiceProvider DecodeRsaPrivateKey(byte[] privkey)
        {
            byte[] E, D, P, Q, DP, DQ, IQ;

            // ------ Set up stream to decode the asn.1 encoded RSA private key ------
            MemoryStream mem = new MemoryStream(privkey);
            //wrap Memory Stream with BinaryReader for easy reading
            BinaryReader binr = new BinaryReader(mem);

            try
            {
                ushort twobytes = binr.ReadUInt16();
                if (twobytes == 0x8130)  //data read as little endian order
                    //(actual data order for Sequence is 30 81)
                    binr.ReadByte();     //advance 1 byte
                else if (twobytes == 0x8230)
                    binr.ReadInt16();    //advance 2 bytes
                else
                    return null;

                twobytes = binr.ReadUInt16();
                if (twobytes != 0x0102)  //version number
                    return null;
                byte bt = binr.ReadByte();
                if (bt != 0x00)
                    return null;

                //------  all private key components are Integer sequences ----
                int elems = GetIntegerSize(binr);
                byte[] modulus = binr.ReadBytes(elems);

                elems = GetIntegerSize(binr);
                E = binr.ReadBytes(elems);

                elems = GetIntegerSize(binr);
                D = binr.ReadBytes(elems);

                elems = GetIntegerSize(binr);
                P = binr.ReadBytes(elems);

                elems = GetIntegerSize(binr);
                Q = binr.ReadBytes(elems);

                elems = GetIntegerSize(binr);
                DP = binr.ReadBytes(elems);

                elems = GetIntegerSize(binr);
                DQ = binr.ReadBytes(elems);

                elems = GetIntegerSize(binr);
                IQ = binr.ReadBytes(elems);

                // ------ create RSACryptoServiceProvider instance ------
                // ------ and initialize with public key           ------

                var cparams = new CspParameters(1,
                    "Microsoft Base Cryptographic Provider v1.0")
                                  {
                                      KeyNumber = 1,
                                      KeyContainerName = Guid.NewGuid().ToString()
                                  };

                var rsa = new RSACryptoServiceProvider(cparams);
                var rsAparams = new RSAParameters
                                    {
                                        Modulus = modulus,
                                        Exponent = E,
                                        D = D,
                                        P = P,
                                        Q = Q,
                                        DP = DP,
                                        DQ = DQ,
                                        InverseQ = IQ
                                    };
                rsa.ImportParameters(rsAparams);
                return rsa;
            }
            catch (Exception)
            {
                return null;
            }
            finally { binr.Close(); }
        }