ext-cryptopp/cmac.h
Jeffrey Walton 37e02f9e0e
Revert AltiVec and Power8 commits
The strategy of "cleanup under-aligned buffers" is not scaling well. Corner cases are still turing up. The library has some corner-case breaks, like old 32-bit Intels. And it still has not solved the AltiVec and Power8 alignment problems.
For now we are backing out the changes and investigating other strategies
2017-09-05 16:28:00 -04:00

68 lines
2.1 KiB
C++

// cmac.h - originally written and placed in the public domain by Wei Dai
//! \file cmac.h
//! \brief Classes for CMAC message authentication code
//! \since Crypto++ 5.6.0
#ifndef CRYPTOPP_CMAC_H
#define CRYPTOPP_CMAC_H
#include "seckey.h"
#include "secblock.h"
NAMESPACE_BEGIN(CryptoPP)
//! \class CMAC_Base
//! \brief CMAC base implementation
//! \since Crypto++ 5.6.0
class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE CMAC_Base : public MessageAuthenticationCode
{
public:
CMAC_Base() : m_counter(0) {}
void UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs &params);
void Update(const byte *input, size_t length);
void TruncatedFinal(byte *mac, size_t size);
unsigned int DigestSize() const {return GetCipher().BlockSize();}
unsigned int OptimalBlockSize() const {return GetCipher().BlockSize();}
unsigned int OptimalDataAlignment() const {return GetCipher().OptimalDataAlignment();}
protected:
friend class EAX_Base;
const BlockCipher & GetCipher() const {return const_cast<CMAC_Base*>(this)->AccessCipher();}
virtual BlockCipher & AccessCipher() =0;
void ProcessBuf();
SecByteBlock m_reg;
unsigned int m_counter;
};
//! \brief CMAC message authentication code
//! \tparam T block cipher
//! \details Template parameter T should be a class derived from BlockCipherDocumentation, for example AES, with a block size of 8, 16, or 32.
//! \sa <a href="http://www.cryptolounge.org/wiki/CMAC">CMAC</a>
//! \since Crypto++ 5.6.0
template <class T>
class CMAC : public MessageAuthenticationCodeImpl<CMAC_Base, CMAC<T> >, public SameKeyLengthAs<T>
{
public:
//! \brief Construct a CMAC
CMAC() {}
//! \brief Construct a CMAC
//! \param key the MAC key
//! \param length the key size, in bytes
CMAC(const byte *key, size_t length=SameKeyLengthAs<T>::DEFAULT_KEYLENGTH)
{this->SetKey(key, length);}
static std::string StaticAlgorithmName() {return std::string("CMAC(") + T::StaticAlgorithmName() + ")";}
private:
BlockCipher & AccessCipher() {return m_cipher;}
typename T::Encryption m_cipher;
};
NAMESPACE_END
#endif