arc4.h
#ifndef CRYPTOPP_ARC4_H
#define CRYPTOPP_ARC4_H
#include "strciphr.h"
NAMESPACE_BEGIN(CryptoPP)
namespace Weak1 {
//! _
class CRYPTOPP_NO_VTABLE ARC4_Base : public VariableKeyLength<16, 1, 256>, public RandomNumberGenerator, public SymmetricCipher, public SymmetricCipherDocumentation
{
public:
~ARC4_Base();
static const char *StaticAlgorithmName() {return "ARC4";}
void GenerateBlock(byte *output, size_t size);
void DiscardBytes(size_t n);
void ProcessData(byte *outString, const byte *inString, size_t length);
bool IsRandomAccess() const {return false;}
bool IsSelfInverting() const {return true;}
bool IsForwardTransformation() const {return true;}
typedef SymmetricCipherFinal<ARC4_Base> Encryption;
typedef SymmetricCipherFinal<ARC4_Base> Decryption;
protected:
void UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs &params);
virtual unsigned int GetDefaultDiscardBytes() const {return 0;}
FixedSizeSecBlock<byte, 256> m_state;
byte m_x, m_y;
};
//! <a href="http://www.weidai.com/scan-mirror/cs.html#RC4">Alleged RC4</a>
DOCUMENTED_TYPEDEF(SymmetricCipherFinal<ARC4_Base>, ARC4)
//! _
class CRYPTOPP_NO_VTABLE MARC4_Base : public ARC4_Base
{
public:
static const char *StaticAlgorithmName() {return "MARC4";}
typedef SymmetricCipherFinal<MARC4_Base> Encryption;
typedef SymmetricCipherFinal<MARC4_Base> Decryption;
protected:
unsigned int GetDefaultDiscardBytes() const {return 256;}
};
//! Modified ARC4: it discards the first 256 bytes of keystream which may be weaker than the rest
DOCUMENTED_TYPEDEF(SymmetricCipherFinal<MARC4_Base>, MARC4)
}
#if CRYPTOPP_ENABLE_NAMESPACE_WEAK >= 1
namespace Weak {using namespace Weak1;} // import Weak1 into CryptoPP::Weak
#else
using namespace Weak1; // import Weak1 into CryptoPP with warning
#ifdef __GNUC__
#warning "You may be using a weak algorithm that has been retained for backwards compatibility. Please '#define CRYPTOPP_ENABLE_NAMESPACE_WEAK 1' before including this .h file and prepend the class name with 'Weak::' to remove this warning."
#else
#pragma message("You may be using a weak algorithm that has been retained for backwards compatibility. Please '#define CRYPTOPP_ENABLE_NAMESPACE_WEAK 1' before including this .h file and prepend the class name with 'Weak::' to remove this warning.")
#endif
#endif
NAMESPACE_END
#endif
StreamTransformation::ProcessData
virtual void ProcessData(byte *outString, const byte *inString, size_t length)=0
encrypt or decrypt an array of bytes of specified length
RandomNumberGenerator::DiscardBytes
virtual void DiscardBytes(size_t n)
generate and discard n bytes
RandomNumberGenerator
interface for random number generators
Definition: cryptlib.h:668
Weak1::ARC4_Base::IsForwardTransformation
bool IsForwardTransformation() const
returns whether this is an encryption object
Definition: arc4.h:25
Weak1::ARC4
Alleged RC4
Definition: arc4.h:39
Weak1::MARC4_Base
_
Definition: arc4.h:42
Weak1::MARC4
Modified ARC4: it discards the first 256 bytes of keystream which may be weaker than the rest...
Definition: arc4.h:55
SymmetricCipher
interface for one direction (encryption or decryption) of a stream cipher or cipher mode ...
Definition: cryptlib.h:610
RandomNumberGenerator::GenerateBlock
virtual void GenerateBlock(byte *output, size_t size)
generate random array of bytes
FixedSizeSecBlock< byte, 256 >
SymmetricCipherDocumentation::Decryption
SymmetricCipher Decryption
implements the SymmetricCipher interface
Definition: seckey.h:206
VariableKeyLength
support query of variable key length, template parameters are default, min, max, multiple (default mu...
Definition: seckey.h:80
strciphr.h
SymmetricCipherDocumentation
Each class derived from this one defines two types, Encryption and Decryption, both of which implemen...
Definition: seckey.h:201
Weak1::ARC4_Base::IsSelfInverting
bool IsSelfInverting() const
returns whether this transformation is self-inverting (e.g. xor with a keystream) ...
Definition: arc4.h:24
SymmetricCipherFinal< ARC4_Base >
Weak1::ARC4_Base
_
Definition: arc4.h:11
SymmetricCipherDocumentation::Encryption
SymmetricCipher Encryption
implements the SymmetricCipher interface
Definition: seckey.h:204
Weak1::ARC4_Base::IsRandomAccess
bool IsRandomAccess() const
returns whether this cipher supports random access
Definition: arc4.h:23
NameValuePairs
interface for retrieving values given their names
Definition: cryptlib.h:224