arc4.h
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// arc4.h - written and placed in the public domain by Wei Dai
//! \file arc4.h
//! \brief Classes for ARC4 cipher
#ifndef CRYPTOPP_ARC4_H
#define CRYPTOPP_ARC4_H
#include "cryptlib.h"
#include "strciphr.h"
#include "secblock.h"
#include "smartptr.h"
NAMESPACE_BEGIN(CryptoPP)
namespace Weak1 {
//! \class ARC4_Base
//! \brief Class specific methods used to operate the cipher.
//! \details Implementations and overrides in \p Base apply to both \p ENCRYPTION and \p DECRYPTION directions
class CRYPTOPP_NO_VTABLE ARC4_Base : public VariableKeyLength<16, 1, 256>, public RandomNumberGenerator, public SymmetricCipher, public SymmetricCipherDocumentation
{
public:
~ARC4_Base();
CRYPTOPP_CONSTEXPR 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 MARC4_Base
//! \brief Class specific methods used to operate the cipher.
//! \details Implementations and overrides in \p Base apply to both \p ENCRYPTION and \p DECRYPTION directions
//! \details MARC4 discards the first 256 bytes of keystream, which may be weaker than the rest
class CRYPTOPP_NO_VTABLE MARC4_Base : public ARC4_Base
{
public:
CRYPTOPP_CONSTEXPR static const char *StaticAlgorithmName() {return "MARC4";}
typedef SymmetricCipherFinal<MARC4_Base> Encryption;
typedef SymmetricCipherFinal<MARC4_Base> Decryption;
protected:
unsigned int GetDefaultDiscardBytes() const {return 256;}
};
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
Weak::MARC4_Base
Class specific methods used to operate the cipher.
Definition: arc4.h:55
SymmetricCipherDocumentation
Provides Encryption and Decryption typedefs used by derived classes to implement a symmetric cipher.
Definition: seckey.h:439
SymmetricCipherFinal< ARC4_Base >
secblock.h
Classes and functions for secure memory allocations.
SymmetricCipher
Interface for one direction (encryption or decryption) of a stream cipher or cipher mode.
Definition: cryptlib.h:1099
smartptr.h
Classes for automatic resource management.
Weak::ARC4_Base::IsSelfInverting
bool IsSelfInverting() const
Determines whether the cipher is self-inverting.
Definition: arc4.h:34
RandomNumberGenerator
Interface for random number generators.
Definition: cryptlib.h:1186
Weak::ARC4_Base
Class specific methods used to operate the cipher.
Definition: arc4.h:21
Weak::MARC4
Definition: arc4.h:67
FixedSizeSecBlock< byte, 256 >
Weak::ARC4_Base::IsForwardTransformation
bool IsForwardTransformation() const
Determines if the cipher is being operated in its forward direction.
Definition: arc4.h:35
Weak::ARC4_Base::IsRandomAccess
bool IsRandomAccess() const
Determines whether the cipher supports random access.
Definition: arc4.h:33
Weak::ARC4
Alleged RC4
Definition: arc4.h:49
CryptoPP
Crypto++ library namespace.
Weak
Namespace containing weak and wounded algorithms.
Definition: arc4.cpp:14
NameValuePairs
Interface for retrieving values given their names.
Definition: cryptlib.h:277
cryptlib.h
Abstract base classes that provide a uniform interface to this library.
strciphr.h
Classes for implementing stream ciphers.
VariableKeyLength
Inherited by keyed algorithms with variable key length.
Definition: seckey.h:177