hondacrx
69 lines
1.9 KiB
C#
69 lines
1.9 KiB
C#
/*
|
|
* Copyright (C) 2012-2014 Arctium Emulation<http://arctium.org>
|
|
* Copyright (C) 2012-2020 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/>.
|
|
*/
|
|
|
|
namespace Framework.Cryptography
|
|
{
|
|
//Thx Fabian over at Arctium.
|
|
public sealed class SARC4
|
|
{
|
|
public SARC4()
|
|
{
|
|
_s = new byte[0x100];
|
|
_tmp = 0;
|
|
_tmp2 = 0;
|
|
}
|
|
|
|
public void PrepareKey(byte[] key)
|
|
{
|
|
for (int i = 0; i < 0x100; i++)
|
|
_s[i] = (byte)i;
|
|
|
|
var j = 0;
|
|
for (int i = 0; i < 0x100; i++)
|
|
{
|
|
j = (byte)((j + key[i % key.Length] + _s[i]) & 255);
|
|
|
|
var tempS = _s[i];
|
|
|
|
_s[i] = _s[j];
|
|
_s[j] = tempS;
|
|
}
|
|
}
|
|
|
|
public void ProcessBuffer(byte[] data, int length)
|
|
{
|
|
for (int i = 0; i < length; i++)
|
|
{
|
|
_tmp = (byte)((_tmp + 1) % 0x100);
|
|
_tmp2 = (byte)((_tmp2 + _s[_tmp]) % 0x100);
|
|
|
|
var sTemp = _s[_tmp];
|
|
|
|
_s[_tmp] = _s[_tmp2];
|
|
_s[_tmp2] = sTemp;
|
|
|
|
data[i] = (byte)(_s[(_s[_tmp] + _s[_tmp2]) % 0x100] ^ data[i]);
|
|
}
|
|
}
|
|
|
|
byte[] _s;
|
|
byte _tmp;
|
|
byte _tmp2;
|
|
}
|
|
}
|