Sha512tDigest
using Org.BouncyCastle.Utilities;
using System;
namespace Org.BouncyCastle.Crypto.Digests
{
public class Sha512tDigest : LongDigest
{
private const ulong A5 = 11936128518282651045;
private readonly int digestLength;
private ulong H1t;
private ulong H2t;
private ulong H3t;
private ulong H4t;
private ulong H5t;
private ulong H6t;
private ulong H7t;
private ulong H8t;
public override string AlgorithmName => "SHA-512/" + (digestLength * 8).ToString();
public Sha512tDigest(int bitLength)
{
if (bitLength >= 512)
throw new ArgumentException("cannot be >= 512", "bitLength");
if (bitLength % 8 != 0)
throw new ArgumentException("needs to be a multiple of 8", "bitLength");
if (bitLength == 384)
throw new ArgumentException("cannot be 384 use SHA384 instead", "bitLength");
digestLength = bitLength / 8;
tIvGenerate(digestLength * 8);
Reset();
}
public Sha512tDigest(Sha512tDigest t)
: base(t)
{
digestLength = t.digestLength;
Reset(t);
}
public override int GetDigestSize()
{
return digestLength;
}
public override int DoFinal(byte[] output, int outOff)
{
Finish();
UInt64_To_BE(H1, output, outOff, digestLength);
UInt64_To_BE(H2, output, outOff + 8, digestLength - 8);
UInt64_To_BE(H3, output, outOff + 16, digestLength - 16);
UInt64_To_BE(H4, output, outOff + 24, digestLength - 24);
UInt64_To_BE(H5, output, outOff + 32, digestLength - 32);
UInt64_To_BE(H6, output, outOff + 40, digestLength - 40);
UInt64_To_BE(H7, output, outOff + 48, digestLength - 48);
UInt64_To_BE(H8, output, outOff + 56, digestLength - 56);
Reset();
return digestLength;
}
public override void Reset()
{
base.Reset();
H1 = H1t;
H2 = H2t;
H3 = H3t;
H4 = H4t;
H5 = H5t;
H6 = H6t;
H7 = H7t;
H8 = H8t;
}
private void tIvGenerate(int bitLength)
{
H1 = 14964410163792538797;
H2 = 2216346199247487646;
H3 = 11082046791023156622;
H4 = 65953792586715988;
H5 = 17630457682085488500;
H6 = 4512832404995164602;
H7 = 13413544941332994254;
H8 = 18322165818757711068;
Update(83);
Update(72);
Update(65);
Update(45);
Update(53);
Update(49);
Update(50);
Update(47);
if (bitLength > 100) {
Update((byte)(bitLength / 100 + 48));
bitLength %= 100;
Update((byte)(bitLength / 10 + 48));
bitLength %= 10;
Update((byte)(bitLength + 48));
} else if (bitLength > 10) {
Update((byte)(bitLength / 10 + 48));
bitLength %= 10;
Update((byte)(bitLength + 48));
} else {
Update((byte)(bitLength + 48));
}
Finish();
H1t = H1;
H2t = H2;
H3t = H3;
H4t = H4;
H5t = H5;
H6t = H6;
H7t = H7;
H8t = H8;
}
private static void UInt64_To_BE(ulong n, byte[] bs, int off, int max)
{
if (max > 0) {
UInt32_To_BE((uint)(n >> 32), bs, off, max);
if (max > 4)
UInt32_To_BE((uint)n, bs, off + 4, max - 4);
}
}
private static void UInt32_To_BE(uint n, byte[] bs, int off, int max)
{
int num = System.Math.Min(4, max);
while (--num >= 0) {
int num2 = 8 * (3 - num);
bs[off + num] = (byte)(n >> num2);
}
}
public override IMemoable Copy()
{
return new Sha512tDigest(this);
}
public override void Reset(IMemoable other)
{
Sha512tDigest sha512tDigest = (Sha512tDigest)other;
if (digestLength != sha512tDigest.digestLength)
throw new MemoableResetException("digestLength inappropriate in other");
CopyIn(sha512tDigest);
H1t = sha512tDigest.H1t;
H2t = sha512tDigest.H2t;
H3t = sha512tDigest.H3t;
H4t = sha512tDigest.H4t;
H5t = sha512tDigest.H5t;
H6t = sha512tDigest.H6t;
H7t = sha512tDigest.H7t;
H8t = sha512tDigest.H8t;
}
}
}