Crypto++ 8.2 Free C++ class library of cryptographic schemes

Public Member Functions | Static Public Member Functions | Static Public Attributes | List of all members
HMAC< T > Class Template Reference

HMAC. More...

Inheritance diagram for HMAC< T >:

## Public Member Functions
| HMAC ()
| Construct a HMAC.
| HMAC (const byte *key, size_t length=HMAC_Base::DEFAULT_KEYLENGTH)
| Construct a HMAC. More...
std::string | AlgorithmName () const
| Provides the name of this algorithm. More...
std::string | AlgorithmProvider () const
| Retrieve the provider of this algorithm. More...
Public Member Functions inherited from AlgorithmImpl< SimpleKeyingInterfaceImpl< HMAC_Base, HMAC< T > >, HMAC< T > >
std::string | AlgorithmName () const
| The algorithm name. More...
Public Member Functions inherited from SimpleKeyingInterfaceImpl< HMAC_Base, HMAC< T > >
size_t | MinKeyLength () const
| The minimum key length used by the algorithm. More...
size_t | MaxKeyLength () const
| The maximum key length used by the algorithm. More...
size_t | DefaultKeyLength () const
| The default key length used by the algorithm. More...
size_t | GetValidKeyLength (size_t keylength) const
| Provides a valid key length for the algorithm. More...
SimpleKeyingInterface::IV_Requirement | IVRequirement () const
| The default IV requirements for the algorithm. More...
unsigned int | IVSize () const
| The initialization vector length for the algorithm. More...
Public Member Functions inherited from HMAC_Base
| HMAC_Base ()
| Construct a HMAC_Base.
void | UncheckedSetKey (const byte *userKey, unsigned int keylength, const NameValuePairs &params)
| Sets the key for this object without performing parameter validation. More...
void | Restart ()
| Restart the hash. More...
void | Update (const byte *input, size_t length)
| Updates a hash with additional input. More...
void | TruncatedFinal (byte *mac, size_t size)
| Computes the hash of the current message. More...
unsigned int | OptimalBlockSize () const
| Provides the input block size most efficient for this hash. More...
unsigned int | DigestSize () const
| Provides the digest size of the hash. More...
Public Member Functions inherited from SimpleKeyingInterface
virtual bool | IsValidKeyLength (size_t keylength) const
| Returns whether keylength is a valid key length. More...
virtual void | SetKey (const byte *key, size_t length, const NameValuePairs &params=g_nullNameValuePairs)
| Sets or reset the key of this object. More...
void | SetKeyWithRounds (const byte *key, size_t length, int rounds)
| Sets or reset the key of this object. More...
void | SetKeyWithIV (const byte *key, size_t length, const byte *iv, size_t ivLength)
| Sets or reset the key of this object. More...
void | SetKeyWithIV (const byte *key, size_t length, const byte *iv)
| Sets or reset the key of this object. More...
bool | IsResynchronizable () const
| Determines if the object can be resynchronized. More...
bool | CanUseRandomIVs () const
| Determines if the object can use random IVs. More...
bool | CanUsePredictableIVs () const
| Determines if the object can use random but possibly predictable IVs. More...
bool | CanUseStructuredIVs () const
| Determines if the object can use structured IVs. More...
unsigned int | DefaultIVLength () const
| Provides the default size of an IV. More...
virtual unsigned int | MinIVLength () const
| Provides the minimum size of an IV. More...
virtual unsigned int | MaxIVLength () const
| Provides the maximum size of an IV. More...
virtual void | Resynchronize (const byte *iv, int ivLength=-1)
| Resynchronize with an IV. More...
virtual void | GetNextIV (RandomNumberGenerator &rng, byte *iv)
| Retrieves a secure IV for the next message. More...
Public Member Functions inherited from HashTransformation
HashTransformation & | Ref ()
| Provides a reference to this object. More...
virtual byte * | CreateUpdateSpace (size_t &size)
| Request space which can be written into by the caller. More...
virtual void | Final (byte *digest)
| Computes the hash of the current message. More...
unsigned int | TagSize () const
| Provides the tag size of the hash. More...
virtual unsigned int | BlockSize () const
| Provides the block size of the compression function. More...
virtual unsigned int | OptimalDataAlignment () const
| Provides input and output data alignment for optimal performance. More...
virtual void | CalculateDigest (byte *digest, const byte *input, size_t length)
| Updates the hash with additional input and computes the hash of the current message. More...
virtual bool | Verify (const byte *digest)
| Verifies the hash of the current message. More...
virtual bool | VerifyDigest (const byte *digest, const byte *input, size_t length)
| Updates the hash with additional input and verifies the hash of the current message. More...
virtual void | CalculateTruncatedDigest (byte *digest, size_t digestSize, const byte *input, size_t length)
| Updates the hash with additional input and computes the hash of the current message. More...
virtual bool | TruncatedVerify (const byte *digest, size_t digestLength)
| Verifies the hash of the current message. More...
virtual bool | VerifyTruncatedDigest (const byte *digest, size_t digestLength, const byte *input, size_t length)
| Updates the hash with additional input and verifies the hash of the current message. More...
Public Member Functions inherited from Algorithm
| Algorithm (bool checkSelfTestStatus=true)
| Interface for all crypto algorithms. More...
Public Member Functions inherited from Clonable
virtual Clonable * | Clone () const
| Copies this object. More...

## Static Public Member Functions
static std::string | StaticAlgorithmName ()
Static Public Member Functions inherited from AlgorithmImpl< SimpleKeyingInterfaceImpl< HMAC_Base, HMAC< T > >, HMAC< T > >
static std::string CRYPTOPP_API | StaticAlgorithmName ()
| The algorithm name. More...
Static Public Member Functions inherited from VariableKeyLength< 16, 0, INT_MAX >
static size_t CRYPTOPP_API | StaticGetValidKeyLength (size_t keylength)
| Provides a valid key length for the algorithm provided by a static function. More...

## Static Public Attributes
static const int | DIGESTSIZE =T::DIGESTSIZE
static const int | BLOCKSIZE =T::BLOCKSIZE
Static Public Attributes inherited from VariableKeyLength< 16, 0, INT_MAX >
static const int | MIN_KEYLENGTH
| The minimum key length used by the algorithm provided as a constant. More...
static const int | MAX_KEYLENGTH
| The maximum key length used by the algorithm provided as a constant. More...
static const int | DEFAULT_KEYLENGTH
| The default key length used by the algorithm provided as a constant. More...
static const int | KEYLENGTH_MULTIPLE
| The key length multiple used by the algorithm provided as a constant. More...
static const int | IV_REQUIREMENT
| The default IV requirements for the algorithm provided as a constant. More...
static const int | IV_LENGTH
| The default initialization vector length for the algorithm provided as a constant. More...

## Additional Inherited Members
Public Types inherited from SimpleKeyingInterface
enum | IV_Requirement { UNIQUE_IV = 0, RANDOM_IV, UNPREDICTABLE_RANDOM_IV, INTERNALLY_GENERATED_IV, NOT_RESYNCHRONIZABLE }
| Secure IVs requirements as enumerated values. More...

## Detailed Description

### template<class T>
class HMAC< T >

HMAC.

Template Parameters

  T | HashTransformation derived class

HMAC derives from MessageAuthenticationCodeImpl. It calculates the HMAC using `HMAC(K, text) = H(K XOR opad, H(K XOR ipad, text))`.

See also
  HMAC

Since
  Crypto++ 2.1

Definition at line 52 of file hmac.h.

## Constructor & Destructor Documentation

## ◆ HMAC()

template<class T>

HMAC< T >::HMAC | ( | const byte * | key,
|  | size_t | length = `HMAC_Base::DEFAULT_KEYLENGTH`
| ) |  |
| inline

Construct a HMAC.

Parameters

  key | the HMAC key
  length | the size of the HMAC key

Definition at line 65 of file hmac.h.

## Member Function Documentation

## ◆ AlgorithmName()

template<class T>

std::string HMAC< T >::AlgorithmName | ( |  | ) | const
| inline virtual

Provides the name of this algorithm.

Returns
  the standard algorithm name

The standard algorithm name can be a name like `AES` or `AES/GCM`. Some algorithms do not have standard names yet. For example, there is no standard algorithm name for Shoup's ECIES.

Note
  AlgorithmName is not universally implemented yet.

Reimplemented from Algorithm.

Definition at line 69 of file hmac.h.

## ◆ AlgorithmProvider()

template<class T>

std::string HMAC< T >::AlgorithmProvider | ( |  | ) | const
| inline virtual

Retrieve the provider of this algorithm.

Returns
  the algorithm provider

The algorithm provider can be a name like "C++", "SSE", "NEON", "AESNI", "ARMv8" and "Power8". C++ is standard C++ code. Other labels, like SSE, usually indicate a specialized implementation using instructions from a higher instruction set architecture (ISA). Future labels may include external hardware like a hardware security module (HSM).

Generally speaking Wei Dai's original IA-32 ASM code falls under "SSE2". Labels like "SSSE3" and "SSE4.1" follow after Wei's code and use intrinsics instead of ASM.

Algorithms which combine different instructions or ISAs provide the dominant one. For example on x86 `AES/GCM` returns "AESNI" rather than "CLMUL" or "AES+SSE4.1" or "AES+CLMUL" or "AES+SSE4.1+CLMUL".

Note
  Provider is not universally implemented yet.

Since
  Crypto++ 8.0

Reimplemented from Algorithm.

Definition at line 70 of file hmac.h.

The documentation for this class was generated from the following file:

- hmac.h