Files
easy7zip/CPP/7zip/Crypto/WzAES/WzAES.h
Igor Pavlov 980e181dcc 4.50 beta
2016-05-28 00:15:52 +01:00

120 lines
2.8 KiB
C++
Executable File

// WzAES.h
/*
This code implements Brian Gladman's scheme
specified in password Based File Encryption Utility:
- AES encryption (128,192,256-bit) in Counter (CTR) mode.
- HMAC-SHA1 authentication for encrypted data (10 bytes)
- Keys are derived by PPKDF2(RFC2898)-HMAC-SHA1 from ASCII password and
Salt (saltSize = aesKeySize / 2).
- 2 bytes contain Password Verifier's Code
*/
#ifndef __CRYPTO_WZ_AES_H
#define __CRYPTO_WZ_AES_H
#include "../Hash/HmacSha1.h"
#include "Common/MyCom.h"
#include "Common/Buffer.h"
#include "Common/MyVector.h"
#include "../../ICoder.h"
#include "../../IPassword.h"
extern "C"
{
#include "../../../../C/Crypto/Aes.h"
}
namespace NCrypto {
namespace NWzAES {
const unsigned int kSaltSizeMax = 16;
const unsigned int kMacSize = 10;
const UInt32 kPasswordSizeMax = 99; // 128;
// Password Verification Code Size
const unsigned int kPwdVerifCodeSize = 2;
class CKeyInfo
{
public:
Byte KeySizeMode; // 1 - 128-bit , 2 - 192-bit , 3 - 256-bit
Byte Salt[kSaltSizeMax];
Byte PwdVerifComputed[kPwdVerifCodeSize];
CByteBuffer Password;
UInt32 GetKeySize() const { return (8 * (KeySizeMode & 3) + 8); }
UInt32 GetSaltSize() const { return (4 * (KeySizeMode & 3) + 4); }
CKeyInfo() { Init(); }
void Init() { KeySizeMode = 3; }
};
class CBaseCoder:
public ICompressFilter,
public ICryptoSetPassword,
public CMyUnknownImp
{
protected:
CKeyInfo _key;
UInt32 _counter[AES_BLOCK_SIZE / 4];
Byte _buffer[AES_BLOCK_SIZE];
NSha1::CHmac _hmac;
unsigned int _blockPos;
Byte _pwdVerifFromArchive[kPwdVerifCodeSize];
void EncryptData(Byte *data, UInt32 size);
CAes Aes;
public:
STDMETHOD(Init)();
STDMETHOD_(UInt32, Filter)(Byte *data, UInt32 size) = 0;
STDMETHOD(CryptoSetPassword)(const Byte *data, UInt32 size);
UInt32 GetHeaderSize() const { return _key.GetSaltSize() + kPwdVerifCodeSize; }
};
class CEncoder:
public CBaseCoder
// public ICompressWriteCoderProperties
{
public:
MY_UNKNOWN_IMP1(ICryptoSetPassword)
// ICompressWriteCoderProperties
// STDMETHOD(WriteCoderProperties)(ISequentialOutStream *outStream);
STDMETHOD_(UInt32, Filter)(Byte *data, UInt32 size);
HRESULT WriteHeader(ISequentialOutStream *outStream);
HRESULT WriteFooter(ISequentialOutStream *outStream);
bool SetKeyMode(Byte mode)
{
if (mode < 1 || mode > 3)
return false;
_key.KeySizeMode = mode;
return true;
}
};
class CDecoder:
public CBaseCoder,
public ICompressSetDecoderProperties2
{
public:
MY_UNKNOWN_IMP2(
ICryptoSetPassword,
ICompressSetDecoderProperties2)
STDMETHOD_(UInt32, Filter)(Byte *data, UInt32 size);
STDMETHOD(SetDecoderProperties2)(const Byte *data, UInt32 size);
HRESULT ReadHeader(ISequentialInStream *inStream);
bool CheckPasswordVerifyCode();
HRESULT CheckMac(ISequentialInStream *inStream, bool &isOK);
};
}}
#endif