Files
CypherCore/Source/Framework/Cryptography/SessionKeyGeneration.cs
T
2019-01-01 12:01:55 -05:00

69 lines
1.9 KiB
C#

/*
* Copyright (C) 2012-2019 CypherCore <http://github.com/CypherCore>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
using System.Security.Cryptography;
namespace Framework.Cryptography
{
public class SessionKeyGenerator
{
public SessionKeyGenerator(byte[] buff, int size)
{
int halfSize = size / 2;
sh = SHA256.Create();
sh.TransformFinalBlock(buff, 0, halfSize);
o1 = sh.Hash;
sh.Initialize();
sh.TransformFinalBlock(buff, halfSize, size - halfSize);
o2 = sh.Hash;
FillUp();
}
public void Generate(byte[] buf, uint sz)
{
for (uint i = 0; i < sz; ++i)
{
if (taken == 32)
FillUp();
buf[i] = o0[taken];
taken++;
}
}
void FillUp()
{
sh.Initialize();
sh.TransformBlock(o1, 0, 32, o1, 0);
sh.TransformBlock(o0, 0, 32, o0, 0);
sh.TransformFinalBlock(o2, 0, 32);
o0 = sh.Hash;
taken = 0;
}
SHA256 sh;
uint taken;
byte[] o0 = new byte[32];
byte[] o1 = new byte[32];
byte[] o2 = new byte[32];
}
}