Crypto++  5.6.5
Free C++ class library of cryptographic schemes
Public Member Functions | List of all members
SipHash< C, D, T_128bit > Class Template Reference

SipHash message authentication code. More...

+ Inheritance diagram for SipHash< C, D, T_128bit >:

Public Member Functions

 SipHash ()
 Create a SipHash.
 
 SipHash (const byte *key, unsigned int length)
 Create a SipHash. More...
 
- Public Member Functions inherited from SipHash_Base< C, D, T_128bit >
virtual unsigned int DigestSize () const
 Provides the digest size of the hash. More...
 
virtual size_t MinKeyLength () const
 Returns smallest valid key length. More...
 
virtual size_t MaxKeyLength () const
 Returns largest valid key length. More...
 
virtual size_t DefaultKeyLength () const
 Returns default key length. More...
 
virtual size_t GetValidKeyLength (size_t keylength) const
 Returns a valid key length for the algorithm. More...
 
virtual IV_Requirement IVRequirement () const
 Minimal requirement for secure IVs. More...
 
virtual unsigned int IVSize () const
 Returns length of the IV accepted by this object. More...
 
virtual unsigned int OptimalBlockSize () const
 Provides the input block size most efficient for this hash. More...
 
virtual unsigned int OptimalDataAlignment () const
 Provides input and output data alignment for optimal performance. More...
 
virtual void Update (const byte *input, size_t length)
 Updates a hash with additional input. More...
 
virtual void TruncatedFinal (byte *digest, size_t digestSize)
 Computes the hash of the current message. 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
HashTransformationRef ()
 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 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...
 
virtual std::string AlgorithmName () const
 Provides the name of this algorithm. More...
 
- Public Member Functions inherited from Clonable
virtual ClonableClone () const
 Copies this object. 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...
 
- Static Public Member Functions inherited from SipHash_Base< C, D, T_128bit >
static std::string StaticAlgorithmName ()
 
- Static Public Member Functions inherited from SipHash_Info< T_128bit >
static const char * StaticAlgorithmName ()
 
- Static Public Member Functions inherited from FixedKeyLength< 16 >
static size_t StaticGetValidKeyLength (size_t keylength)
 The default key length for the algorithm provided by a static function. More...
 
- Static Public Attributes inherited from SipHash_Info< T_128bit >
static const int DIGESTSIZE = (T_128bit ? 16 : 8)
 
- Static Public Attributes inherited from FixedKeyLength< 16 >
static const int KEYLENGTH
 The default key length used by the algorithm provided as a constant. More...
 
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 IV_REQUIREMENT
 The default IV requirements for the algorithm provided as a constant. More...
 
static const int IV_LENGTH
 The default IV length used by the algorithm provided as a constant. More...
 

Detailed Description

template<unsigned int C = 2, unsigned int D = 4, bool T_128bit = false>
class SipHash< C, D, T_128bit >

SipHash message authentication code.

Template Parameters
Cthe number of compression rounds
Dthe number of finalization rounds
T_128bitflag indicating 128-bit (true) versus 64-bit (false) digest size

SipHash computes a 64-bit or 128-bit message authentication code from a variable-length message and 128-bit secret key. It was designed to be efficient even for short inputs, with performance comparable to non-cryptographic hash functions.

To create a SipHash-2-4 object with a 64-bit MAC use code similar to the following.

  SecByteBlock key(16);
  prng.GenerateBlock(key, key.size());
  SipHash<2,4,false> hash(key, key.size());
  hash.Update(...);
  hash.Final(...);

To create a SipHash-2-4 object with a 128-bit MAC use code similar to the following.

  SecByteBlock key(16);
  prng.GenerateBlock(key, key.size());
  SipHash<2,4,true> hash(key, key.size());
  hash.Update(...);
  hash.Final(...);
See also
Jean-Philippe Aumasson and Daniel J. Bernstein SipHash: a fast short-input PRF
Since
Crypto++ 6.0

Definition at line 144 of file siphash.h.

Constructor & Destructor Documentation

◆ SipHash()

template<unsigned int C = 2, unsigned int D = 4, bool T_128bit = false>
SipHash< C, D, T_128bit >::SipHash ( const byte *  key,
unsigned int  length 
)
inline

Create a SipHash.

Parameters
keya byte array used to key the cipher
lengththe size of the byte array, in bytes

Definition at line 153 of file siphash.h.


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