Crypto++  8.2
Free C++ class library of cryptographic schemes
cmac.h
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1 // cmac.h - originally written and placed in the public domain by Wei Dai
2 
3 /// \file cmac.h
4 /// \brief Classes for CMAC message authentication code
5 /// \since Crypto++ 5.6.0
6 
7 #ifndef CRYPTOPP_CMAC_H
8 #define CRYPTOPP_CMAC_H
9 
10 #include "seckey.h"
11 #include "secblock.h"
12 
13 NAMESPACE_BEGIN(CryptoPP)
14 
15 /// \brief CMAC base implementation
16 /// \since Crypto++ 5.6.0
17 class CRYPTOPP_DLL CRYPTOPP_NO_VTABLE CMAC_Base : public MessageAuthenticationCode
18 {
19 public:
20 
21  virtual ~CMAC_Base() {}
22 
23  CMAC_Base() : m_counter(0) {}
24 
25  void UncheckedSetKey(const byte *key, unsigned int length, const NameValuePairs &params);
26  void Update(const byte *input, size_t length);
27  void TruncatedFinal(byte *mac, size_t size);
28  unsigned int DigestSize() const {return GetCipher().BlockSize();}
29  unsigned int OptimalBlockSize() const {return GetCipher().BlockSize();}
30  unsigned int OptimalDataAlignment() const {return GetCipher().OptimalDataAlignment();}
31  std::string AlgorithmProvider() const {return GetCipher().AlgorithmProvider();}
32 
33 protected:
34  friend class EAX_Base;
35 
36  const BlockCipher & GetCipher() const {return const_cast<CMAC_Base*>(this)->AccessCipher();}
37  virtual BlockCipher & AccessCipher() =0;
38 
39  void ProcessBuf();
40  SecByteBlock m_reg;
41  unsigned int m_counter;
42 };
43 
44 /// \brief CMAC message authentication code
45 /// \tparam T block cipher
46 /// \details Template parameter T should be a class derived from BlockCipherDocumentation, for example AES, with a block size of 8, 16, or 32.
47 /// \sa <a href="http://www.cryptolounge.org/wiki/CMAC">CMAC</a>
48 /// \since Crypto++ 5.6.0
49 template <class T>
50 class CMAC : public MessageAuthenticationCodeImpl<CMAC_Base, CMAC<T> >, public SameKeyLengthAs<T>
51 {
52 public:
53  /// \brief Construct a CMAC
54  CMAC() {}
55  /// \brief Construct a CMAC
56  /// \param key the MAC key
57  /// \param length the key size, in bytes
58  CMAC(const byte *key, size_t length=SameKeyLengthAs<T>::DEFAULT_KEYLENGTH)
59  {this->SetKey(key, length);}
60 
61  static std::string StaticAlgorithmName() {return std::string("CMAC(") + T::StaticAlgorithmName() + ")";}
62 
63 private:
64  BlockCipher & AccessCipher() {return m_cipher;}
65  typename T::Encryption m_cipher;
66 };
67 
68 NAMESPACE_END
69 
70 #endif
Interface for message authentication codes.
Definition: cryptlib.h:1266
virtual void SetKey(const byte *key, size_t length, const NameValuePairs &params=g_nullNameValuePairs)
Sets or reset the key of this object.
Definition: cryptlib.cpp:59
unsigned int DigestSize() const
Provides the digest size of the hash.
Definition: cmac.h:28
EAX block cipher base implementation.
Definition: eax.h:18
SecBlock<byte> typedef.
Definition: secblock.h:1058
Interface for one direction (encryption or decryption) of a block cipher.
Definition: cryptlib.h:1250
CMAC message authentication code.
Definition: cmac.h:50
Classes and functions for secure memory allocations.
unsigned int OptimalDataAlignment() const
Provides input and output data alignment for optimal performance.
Definition: cmac.h:30
CMAC()
Construct a CMAC.
Definition: cmac.h:54
Classes and functions for implementing secret key algorithms.
unsigned int OptimalBlockSize() const
Provides the input block size most efficient for this hash.
Definition: cmac.h:29
Provides a base implementation of Algorithm and SimpleKeyingInterface for message authentication code...
Definition: seckey.h:362
Provides key lengths based on another class's key length.
Definition: seckey.h:217
CMAC(const byte *key, size_t length=SameKeyLengthAs< T >::DEFAULT_KEYLENGTH)
Construct a CMAC.
Definition: cmac.h:58
std::string AlgorithmProvider() const
Retrieve the provider of this algorithm.
Definition: cmac.h:31
CMAC base implementation.
Definition: cmac.h:17
Crypto++ library namespace.
Interface for retrieving values given their names.
Definition: cryptlib.h:293