Main Page | Namespace List | Class Hierarchy | Alphabetical List | Class List | File List | Class Members | File Members

SHA256 Class Reference

#include <sha.h>

Inheritance diagram for SHA256:

IteratedHashWithStaticTransform< word32, BigEndian, 64, 32, SHA256 > ClonableImpl< SHA256, AlgorithmImpl< IteratedHash< word32, BigEndian, T_BlockSize >, SHA256 > > AlgorithmImpl< IteratedHash< word32, BigEndian, T_BlockSize >, SHA256 > IteratedHash< word32, BigEndian, T_BlockSize > IteratedHashBase2< word32, BigEndian, HashTransformation > IteratedHashBase< word32, HashTransformation > HashTransformation Algorithm Clonable List of all members.

Detailed Description

implements the SHA-256 standard

Definition at line 20 of file sha.h.

Public Types

typedef BigEndian ByteOrderClass
typedef IteratedHashBase<
word32, HashTransformation
>::HashWordType 		HashWordType

Public Member Functions

unsigned int DigestSize () const
 size of the hash returned by Final()
Clonable * Clone () const
 this is not implemented by most classes yet
std::string AlgorithmName () const
 returns name of this algorithm, not universally implemented yet
void TruncatedFinal (byte *digest, unsigned int size)
 truncated version of Final()
unsigned int BlockSize () const
 block size of underlying compression function, or 0 if not block based
unsigned int OptimalBlockSize () const
 input to Update() should have length a multiple of this for optimal speed
unsigned int OptimalDataAlignment () const
 returns how input should be aligned for optimal performance
void Update (const byte *input, unsigned int length)
 process more input
byte * CreateUpdateSpace (unsigned int &size)
 request space to write input into
void Restart ()
 discard the current state, and restart with a new message
virtual void Final (byte *digest)
 compute hash for current message, then restart for a new message
virtual void CalculateDigest (byte *digest, const byte *input, unsigned int length)
 use this if your input is in one piece and you don't want to call Update() and Final() separately
virtual bool Verify (const byte *digest)
 verify that digest is a valid digest for the current message, then reinitialize the object
virtual bool VerifyDigest (const byte *digest, const byte *input, unsigned int length)
 use this if your input is in one piece and you don't want to call Update() and Verify() separately
virtual void CalculateTruncatedDigest (byte *digest, unsigned int digestSize, const byte *input, unsigned int length)
 truncated version of CalculateDigest()
virtual bool TruncatedVerify (const byte *digest, unsigned int digestLength)
 truncated version of Verify()
virtual bool VerifyTruncatedDigest (const byte *digest, unsigned int digestLength, const byte *input, unsigned int length)
 truncated version of VerifyDigest()

Static Public Member Functions

void InitState (HashWordType *state)
void Transform (word32 *digest, const word32 *data)
const char * StaticAlgorithmName ()
void CorrectEndianess (HashWordType *out, const HashWordType *in, unsigned int byteCount)

Static Public Attributes

CompileAssert<((BLOCKSIZE
&(BLOCKSIZE-1))==0) 		cryptopp_assert___LINE__ )

Protected Member Functions

void HashEndianCorrectedBlock (const word32 *data)
virtual void HashEndianCorrectedBlock (const HashWordType *data)=0
void Init ()
void HashBlock (const HashWordType *input)
virtual void HashBlock (const word32 *input)=0
void SetBlockSize (unsigned int blockSize)
void SetStateSize (unsigned int stateSize)
word32 GetBitCountHi () const
word32 GetBitCountLo () const
virtual unsigned int HashMultipleBlocks (const word32 *input, unsigned int length)
void PadLastBlock (unsigned int lastBlockSize, byte padFirst=0x80)
void ThrowIfInvalidTruncatedSize (unsigned int size) const

Protected Attributes

SecBlock< word32 > m_data
SecBlock< word32 > m_digest

Static Protected Attributes

const word32 K [64]

Member Function Documentation

virtual void HashTransformation::Final (  byte *  digest  )  [inline, virtual, inherited]
 

compute hash for current message, then restart for a new message

Precondition:
size of digest == DigestSize().
Definition at line 532 of file cryptlib.h.

Referenced by PKCS5_PBKDF2_HMAC< T >::DeriveKey(), HashFilter::Put2(), and HMAC_Base::TruncatedFinal().

virtual bool HashTransformation::Verify (  const byte *  digest  )  [inline, virtual, inherited]
 

verify that digest is a valid digest for the current message, then reinitialize the object

Default implementation is to call Final() and do a bitwise comparison between its output and digest. Definition at line 558 of file cryptlib.h.

Member Data Documentation

const word32 SHA256::K [static, protected]
 

Initial value:

 {
        0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
        0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
        0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
        0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
        0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
        0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
        0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
        0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
        0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
        0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
        0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
        0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
        0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
        0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
        0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
        0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
}
Definition at line 150 of file sha.cpp.

The documentation for this class was generated from the following files:
Generated on Wed Jul 21 19:16:08 2004 for Crypto++ by doxygen 1.3.7-20040704