BraintreeEncryption.Library.BouncyCastle.Crypto.Digests.Sha1Digest.ProcessBlock C# (CSharp) Method

        internal override void ProcessBlock()
        {
            //
            // expand 16 word block into 80 word block.
            //
            for (int i = 16; i < 80; i++)
            {
                uint t = X[i - 3] ^ X[i - 8] ^ X[i - 14] ^ X[i - 16];
                X[i] = t << 1 | t >> 31;
            }

            //
            // set up working variables.
            //
            uint A = H1;
            uint B = H2;
            uint C = H3;
            uint D = H4;
            uint E = H5;

            //
            // round 1
            //
            int idx = 0;

            for (int j = 0; j < 4; j++)
            {
                // E = rotateLeft(A, 5) + F(B, C, D) + E + X[idx++] + Y1
                // B = rotateLeft(B, 30)
                E += (A << 5 | (A >> 27)) + F(B, C, D) + X[idx++] + Y1;
                B = B << 30 | (B >> 2);

                D += (E << 5 | (E >> 27)) + F(A, B, C) + X[idx++] + Y1;
                A = A << 30 | (A >> 2);

                C += (D << 5 | (D >> 27)) + F(E, A, B) + X[idx++] + Y1;
                E = E << 30 | (E >> 2);

                B += (C << 5 | (C >> 27)) + F(D, E, A) + X[idx++] + Y1;
                D = D << 30 | (D >> 2);

                A += (B << 5 | (B >> 27)) + F(C, D, E) + X[idx++] + Y1;
                C = C << 30 | (C >> 2);
            }

            //
            // round 2
            //
            for (int j = 0; j < 4; j++)
            {
                // E = rotateLeft(A, 5) + H(B, C, D) + E + X[idx++] + Y2
                // B = rotateLeft(B, 30)
                E += (A << 5 | (A >> 27)) + H(B, C, D) + X[idx++] + Y2;
                B = B << 30 | (B >> 2);

                D += (E << 5 | (E >> 27)) + H(A, B, C) + X[idx++] + Y2;
                A = A << 30 | (A >> 2);

                C += (D << 5 | (D >> 27)) + H(E, A, B) + X[idx++] + Y2;
                E = E << 30 | (E >> 2);

                B += (C << 5 | (C >> 27)) + H(D, E, A) + X[idx++] + Y2;
                D = D << 30 | (D >> 2);

                A += (B << 5 | (B >> 27)) + H(C, D, E) + X[idx++] + Y2;
                C = C << 30 | (C >> 2);
            }

            //
            // round 3
            //
            for (int j = 0; j < 4; j++)
            {
                // E = rotateLeft(A, 5) + G(B, C, D) + E + X[idx++] + Y3
                // B = rotateLeft(B, 30)
                E += (A << 5 | (A >> 27)) + G(B, C, D) + X[idx++] + Y3;
                B = B << 30 | (B >> 2);

                D += (E << 5 | (E >> 27)) + G(A, B, C) + X[idx++] + Y3;
                A = A << 30 | (A >> 2);

                C += (D << 5 | (D >> 27)) + G(E, A, B) + X[idx++] + Y3;
                E = E << 30 | (E >> 2);

                B += (C << 5 | (C >> 27)) + G(D, E, A) + X[idx++] + Y3;
                D = D << 30 | (D >> 2);

                A += (B << 5 | (B >> 27)) + G(C, D, E) + X[idx++] + Y3;
                C = C << 30 | (C >> 2);
            }

            //
            // round 4
            //
            for (int j = 0; j < 4; j++)
            {
                // E = rotateLeft(A, 5) + H(B, C, D) + E + X[idx++] + Y4
                // B = rotateLeft(B, 30)
                E += (A << 5 | (A >> 27)) + H(B, C, D) + X[idx++] + Y4;
                B = B << 30 | (B >> 2);

                D += (E << 5 | (E >> 27)) + H(A, B, C) + X[idx++] + Y4;
                A = A << 30 | (A >> 2);

                C += (D << 5 | (D >> 27)) + H(E, A, B) + X[idx++] + Y4;
                E = E << 30 | (E >> 2);

                B += (C << 5 | (C >> 27)) + H(D, E, A) + X[idx++] + Y4;
                D = D << 30 | (D >> 2);

                A += (B << 5 | (B >> 27)) + H(C, D, E) + X[idx++] + Y4;
                C = C << 30 | (C >> 2);
            }

            H1 += A;
            H2 += B;
            H3 += C;
            H4 += D;
            H5 += E;

            //
            // reset start of the buffer.
            //
            xOff = 0;
            Array.Clear(X, 0, 16);
        }