mirror of
https://github.com/wismna/ModernKeePassLib.git
synced 2025-10-03 23:50:20 -04:00
Setup solution
This commit is contained in:
142
ModernKeePassLib/Cryptography/KeyDerivation/KdfEngine.cs
Normal file
142
ModernKeePassLib/Cryptography/KeyDerivation/KdfEngine.cs
Normal file
@@ -0,0 +1,142 @@
|
||||
/*
|
||||
KeePass Password Safe - The Open-Source Password Manager
|
||||
Copyright (C) 2003-2019 Dominik Reichl <dominik.reichl@t-online.de>
|
||||
|
||||
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 2 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, write to the Free Software
|
||||
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
||||
*/
|
||||
|
||||
using System;
|
||||
using System.Collections.Generic;
|
||||
using System.Diagnostics;
|
||||
using System.Text;
|
||||
|
||||
namespace ModernKeePassLib.Cryptography.KeyDerivation
|
||||
{
|
||||
public abstract class KdfEngine
|
||||
{
|
||||
public abstract PwUuid Uuid
|
||||
{
|
||||
get;
|
||||
}
|
||||
|
||||
public abstract string Name
|
||||
{
|
||||
get;
|
||||
}
|
||||
|
||||
public virtual KdfParameters GetDefaultParameters()
|
||||
{
|
||||
return new KdfParameters(this.Uuid);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Generate random seeds and store them in <paramref name="p" />.
|
||||
/// </summary>
|
||||
public virtual void Randomize(KdfParameters p)
|
||||
{
|
||||
Debug.Assert(p != null);
|
||||
Debug.Assert(p.KdfUuid.Equals(this.Uuid));
|
||||
}
|
||||
|
||||
public abstract byte[] Transform(byte[] pbMsg, KdfParameters p);
|
||||
|
||||
public virtual KdfParameters GetBestParameters(uint uMilliseconds)
|
||||
{
|
||||
throw new NotImplementedException();
|
||||
}
|
||||
|
||||
protected void MaximizeParamUInt64(KdfParameters p, string strName,
|
||||
ulong uMin, ulong uMax, uint uMilliseconds, bool bInterpSearch)
|
||||
{
|
||||
if(p == null) { Debug.Assert(false); return; }
|
||||
if(string.IsNullOrEmpty(strName)) { Debug.Assert(false); return; }
|
||||
if(uMin > uMax) { Debug.Assert(false); return; }
|
||||
|
||||
if(uMax > (ulong.MaxValue >> 1))
|
||||
{
|
||||
Debug.Assert(false);
|
||||
uMax = ulong.MaxValue >> 1;
|
||||
|
||||
if(uMin > uMax) { p.SetUInt64(strName, uMin); return; }
|
||||
}
|
||||
|
||||
byte[] pbMsg = new byte[32];
|
||||
for(int i = 0; i < pbMsg.Length; ++i) pbMsg[i] = (byte)i;
|
||||
|
||||
ulong uLow = uMin;
|
||||
ulong uHigh = uMin + 1UL;
|
||||
long tLow = 0;
|
||||
long tHigh = 0;
|
||||
long tTarget = (long)uMilliseconds;
|
||||
|
||||
// Determine range
|
||||
while(uHigh <= uMax)
|
||||
{
|
||||
p.SetUInt64(strName, uHigh);
|
||||
|
||||
// GC.Collect();
|
||||
Stopwatch sw = Stopwatch.StartNew();
|
||||
Transform(pbMsg, p);
|
||||
sw.Stop();
|
||||
|
||||
tHigh = sw.ElapsedMilliseconds;
|
||||
if(tHigh > tTarget) break;
|
||||
|
||||
uLow = uHigh;
|
||||
tLow = tHigh;
|
||||
uHigh <<= 1;
|
||||
}
|
||||
if(uHigh > uMax) { uHigh = uMax; tHigh = 0; }
|
||||
if(uLow > uHigh) uLow = uHigh; // Skips to end
|
||||
|
||||
// Find optimal number of iterations
|
||||
while((uHigh - uLow) >= 2UL)
|
||||
{
|
||||
ulong u = (uHigh + uLow) >> 1; // Binary search
|
||||
// Interpolation search, if possible
|
||||
if(bInterpSearch && (tLow > 0) && (tHigh > tTarget) &&
|
||||
(tLow <= tTarget))
|
||||
{
|
||||
u = uLow + (((uHigh - uLow) * (ulong)(tTarget - tLow)) /
|
||||
(ulong)(tHigh - tLow));
|
||||
if((u >= uLow) && (u <= uHigh))
|
||||
{
|
||||
u = Math.Max(u, uLow + 1UL);
|
||||
u = Math.Min(u, uHigh - 1UL);
|
||||
}
|
||||
else
|
||||
{
|
||||
Debug.Assert(false);
|
||||
u = (uHigh + uLow) >> 1;
|
||||
}
|
||||
}
|
||||
|
||||
p.SetUInt64(strName, u);
|
||||
|
||||
// GC.Collect();
|
||||
Stopwatch sw = Stopwatch.StartNew();
|
||||
Transform(pbMsg, p);
|
||||
sw.Stop();
|
||||
|
||||
long t = sw.ElapsedMilliseconds;
|
||||
if(t == tTarget) { uLow = u; break; }
|
||||
else if(t > tTarget) { uHigh = u; tHigh = t; }
|
||||
else { uLow = u; tLow = t; }
|
||||
}
|
||||
|
||||
p.SetUInt64(strName, uLow);
|
||||
}
|
||||
}
|
||||
}
|
Reference in New Issue
Block a user