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CRC32 Class Reference

#include <crc.h>

Inheritance diagram for CRC32:

HashTransformation Algorithm Clonable List of all members.

Detailed Description

CRC Checksum Calculation.

Definition at line 19 of file crc.h.

Public Types

enum  { DIGESTSIZE = 4 }

Public Member Functions

void Update (const byte *input, unsigned int length)
 process more input

void TruncatedFinal (byte *hash, unsigned int size)
 truncated version of Final()

unsigned int DigestSize () const
 size of the hash returned by Final()

void UpdateByte (byte b)
byte GetCrcByte (unsigned int i) const
virtual byte * CreateUpdateSpace (unsigned int &size)
 request space to write input into

virtual void Final (byte *digest)
 compute hash for current message, then restart for a new message

virtual void Restart ()
 discard the current state, and restart with a new message

virtual unsigned int OptimalBlockSize () const
 input to Update() should have length a multiple of this for optimal speed

virtual unsigned int OptimalDataAlignment () const
 returns how input should be aligned for optimal performance

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()

virtual std::string AlgorithmName () const
 returns name of this algorithm, not universally implemented yet

virtual ClonableClone () const
 this is not implemented by most classes yet


Protected Member Functions

void ThrowIfInvalidTruncatedSize (unsigned int size) const


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 509 of file cryptlib.h.

References HashTransformation::DigestSize(), and HashTransformation::TruncatedFinal().

Referenced by HashTransformation::CalculateDigest().

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 532 of file cryptlib.h.

References HashTransformation::DigestSize(), and HashTransformation::TruncatedVerify().

Referenced by HashTransformation::VerifyDigest().


The documentation for this class was generated from the following files:
Generated on Sun Mar 14 20:44:32 2004 for Crypto++ by doxygen 1.3.6-20040222