static byte[] Sha256Algorithm(byte[] plaintext, Word32[] H0, int numberBits)
{
Block512[] blocks = ConvertPaddedTextToBlock512Array(PadPlainText512(plaintext));
// Define the hash variables and set their initial values.
Word32[] H = H0;
for (int i = 0; i < blocks.Length; i++)
{
Word32[] W = CreateMessageScheduleSha256(blocks[i]);
// Set the working variables a,...,h to the current hash values.
Word32 a = H[0];
Word32 b = H[1];
Word32 c = H[2];
Word32 d = H[3];
Word32 e = H[4];
Word32 f = H[5];
Word32 g = H[6];
Word32 h = H[7];
for (int t = 0; t < 64; t++)
{
Word32 T1 = h + Sigma1_256(e) + Ch(e, f, g) + K256[t] + W[t];
Word32 T2 = Sigma0_256(a) + Maj(a, b, c);
h = g;
g = f;
f = e;
e = d + T1;
d = c;
c = b;
b = a;
a = T1 + T2;
}
// Update the current value of the hash H after processing block i.
H[0] += a;
H[1] += b;
H[2] += c;
H[3] += d;
H[4] += e;
H[5] += f;
H[6] += g;
H[7] += h;
}
// Concatenate all the Word32 Hash Values
byte[] hash = ShaUtilities.Word32ArrayToByteArray(H);
// The number of bytes in the final output hash
int numberBytes = numberBits / 8;
byte[] truncatedHash = new byte[numberBytes];
Array.Copy(hash, truncatedHash, numberBytes);
return(truncatedHash);
}
static byte[] Sha1Algorithm(byte[] plaintext)
{
Block512[] blocks = ConvertPaddedTextToBlock512Array(PadPlainText512(plaintext));
// Define the hash variable and set its initial values.
Word32[] H = new Word32[5];
H0Sha1.CopyTo(H, 0);
for (int i = 0; i < blocks.Length; i++)
{
Word32[] W = CreateMessageScheduleSha1(blocks[i]);
// Set the working variables a,...,e to the current hash values.
Word32 a = H[0];
Word32 b = H[1];
Word32 c = H[2];
Word32 d = H[3];
Word32 e = H[4];
for (int t = 0; t < 80; t++)
{
Word32 T = RotL(5, a) + f(t, b, c, d) + e + K1[t] + W[t];
e = d;
d = c;
c = RotL(30, b);
b = a;
a = T;
}
// Update the current value of the hash H after processing block i.
H[0] += a;
H[1] += b;
H[2] += c;
H[3] += d;
H[4] += e;
}
// Concatenating the final 5 hash words H[0],...,H[4] gives the digest.
// Since each H[i] is 4 bytes, the digest is 5 * 4 = 20 bytes = 160 bits.
return(ShaUtilities.Word32ArrayToByteArray(H));
}