mirror of
https://github.com/moparisthebest/keepass2android
synced 2024-08-13 17:03:49 -04:00
3506e253db
allow write access for kdb (UI not yet completed, but saving done)
128 lines
3.7 KiB
C#
128 lines
3.7 KiB
C#
/*
|
|
Twofish Cipher for KeePass Password Safe
|
|
Copyright (C) 2009-2010 SEG Tech <me@gogogadgetscott.info>
|
|
|
|
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.Text;
|
|
using System.IO;
|
|
using System.Security;
|
|
using System.Security.Cryptography;
|
|
using System.Diagnostics;
|
|
|
|
using KeePassLib;
|
|
using KeePassLib.Cryptography.Cipher;
|
|
|
|
using TwofishCipher.Crypto;
|
|
|
|
namespace TwofishCipher
|
|
{
|
|
public sealed class TwofishCipherEngine : ICipherEngine
|
|
{
|
|
private const CipherMode m_rCipherMode = CipherMode.CBC;
|
|
private const PaddingMode m_rCipherPadding = PaddingMode.PKCS7;
|
|
|
|
private PwUuid m_uuidCipher;
|
|
|
|
public static readonly byte[] TwofishCipherUuidBytes = new byte[]{
|
|
0xAD, 0x68, 0xF2, 0x9F, 0x57, 0x6F, 0x4B, 0xB9,
|
|
0xA3, 0x6A, 0xD4, 0x7A, 0xF9, 0x65, 0x34, 0x6C
|
|
};
|
|
|
|
public TwofishCipherEngine()
|
|
{
|
|
m_uuidCipher = new PwUuid(TwofishCipherUuidBytes);
|
|
}
|
|
|
|
public PwUuid CipherUuid
|
|
{
|
|
get
|
|
{
|
|
Debug.Assert(m_uuidCipher != null);
|
|
return m_uuidCipher;
|
|
}
|
|
}
|
|
|
|
public string DisplayName
|
|
{
|
|
get { return "Twofish (256-Bit Key)"; }
|
|
}
|
|
|
|
private static void ValidateArguments(Stream stream, bool bEncrypt, byte[] pbKey, byte[] pbIV)
|
|
{
|
|
Debug.Assert(stream != null); if(stream == null) throw new ArgumentNullException("stream");
|
|
|
|
Debug.Assert(pbKey != null); if(pbKey == null) throw new ArgumentNullException("pbKey");
|
|
Debug.Assert(pbKey.Length == 32);
|
|
if(pbKey.Length != 32) throw new ArgumentException("Key must be 256 bits wide!");
|
|
|
|
Debug.Assert(pbIV != null); if(pbIV == null) throw new ArgumentNullException("pbIV");
|
|
Debug.Assert(pbIV.Length == 16);
|
|
if(pbIV.Length != 16) throw new ArgumentException("Initialization vector must be 128 bits wide!");
|
|
|
|
if(bEncrypt)
|
|
{
|
|
Debug.Assert(stream.CanWrite);
|
|
if(stream.CanWrite == false) throw new ArgumentException("Stream must be writable!");
|
|
}
|
|
else // Decrypt
|
|
{
|
|
Debug.Assert(stream.CanRead);
|
|
if(stream.CanRead == false) throw new ArgumentException("Encrypted stream must be readable!");
|
|
}
|
|
}
|
|
|
|
private static Stream CreateStream(Stream s, bool bEncrypt, byte[] pbKey, byte[] pbIV)
|
|
{
|
|
ValidateArguments(s, bEncrypt, pbKey, pbIV);
|
|
|
|
Twofish f = new Twofish();
|
|
|
|
byte[] pbLocalIV = new byte[16];
|
|
Array.Copy(pbIV, pbLocalIV, 16);
|
|
f.IV = pbLocalIV;
|
|
|
|
byte[] pbLocalKey = new byte[32];
|
|
Array.Copy(pbKey, pbLocalKey, 32);
|
|
f.KeySize = 256;
|
|
f.Key = pbLocalKey;
|
|
|
|
f.Mode = m_rCipherMode;
|
|
f.Padding = m_rCipherPadding;
|
|
|
|
ICryptoTransform iTransform = (bEncrypt ? f.CreateEncryptor() : f.CreateDecryptor());
|
|
Debug.Assert(iTransform != null);
|
|
if(iTransform == null) throw new SecurityException("Unable to create Twofish transform!");
|
|
|
|
return new CryptoStream(s, iTransform, bEncrypt ? CryptoStreamMode.Write :
|
|
CryptoStreamMode.Read);
|
|
}
|
|
|
|
public Stream EncryptStream(Stream sPlainText, byte[] pbKey, byte[] pbIV)
|
|
{
|
|
return CreateStream(sPlainText, true, pbKey, pbIV);
|
|
}
|
|
|
|
public Stream DecryptStream(Stream sEncrypted, byte[] pbKey, byte[] pbIV)
|
|
{
|
|
return CreateStream(sEncrypted, false, pbKey, pbIV);
|
|
}
|
|
|
|
}
|
|
}
|