SecureHashBase Class Reference

Hash algorithm base class. More...

#include <shashbase.h>

Inheritance diagram for SecureHashBase:

[legend]Collaboration diagram for SecureHashBase:

[legend]List of all members.

Public Member Functions
	SecureHashBase ()
	Constructor; a no-op here.
virtual	~SecureHashBase ()
	Destructor must clean up the hash state.
virtual const Parameters *	GetPar () const
	Returns a pointer to the (normally static) parameters of this hash algorithm.
virtual uint64	FedBytes () const
	Returns how many bytes were already fed (using feed()) since the last reset().
virtual void	reset ()
	Reset the hash; delete the current hash value (as returned by GetHash()).
virtual void	feed (const char *buf, size_t len)
	Feed the hash algo with data.
virtual void	final ()
	Do the final computing of the hash value (padding...).
virtual void	GetHash (char *buf) const
	Query the (current) hash value /message digest.
Static Public Attributes
const Parameters	par
Protected Attributes
uint64	length
	length of hashed data in BYTES.
Private Member Functions
	SecureHashBase (const SecureHashBase &)
	Do not use these:.
void	operator= (const SecureHashBase &)

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Detailed Description

Hash algorithm base class.

Author:

Wolfgang Wieser ] wwieser (a) gmx <*> de [

This is a base class for (mostly cryptographic) hash / message digest algorithms.

If no derived class is used but this class itself, a null-hash (which is always 0) is used.

How to compute a message digest / hash value:

• Reset the hash algorithm using reset() (this is also done by the constructor.)
• Give the hash algorithm input. Call feed() as long as you have input.
• Do final calculation calling final().
• Query the hash value using GetHash().

NOTE: This class is NOT "C++-safe" and you should generally be careful with cryptographic data, so it is best to manage (de)allocation of these objects in a higher order.

Definition at line 51 of file shashbase.h.

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Constructor & Destructor Documentation

SecureHashBase::SecureHashBase (  const SecureHashBase &   )  [private]

Do not use these:.

SecureHashBase::SecureHashBase (   )  [inline]

Constructor; a no-op here. Definition at line 77 of file shashbase.h. References length.

virtual SecureHashBase::~SecureHashBase (   )  [inline, virtual]

Destructor must clean up the hash state. Definition at line 79 of file shashbase.h.

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Member Function Documentation

uint64 SecureHashBase::FedBytes (   )  const [virtual]

Returns how many bytes were already fed (using feed()) since the last reset(). Reimplemented in CRC32Hash, RMD160Hash, SHA0Hash, and SHA1Hash. Definition at line 29 of file shashbase.cc. References length, and uint64.

void SecureHashBase::feed (  const char *  buf, size_t  len )  [virtual]

Feed the hash algo with data. Input the passed data into the hash algorithm and go on computing the hash value. buf does not have to be aligned. Note: Things are normally faster, if (len%GetPar()->block_size)=0, i.e. the length is always a multiple of the block size. Reimplemented in CRC32Hash, RMD160Hash, SHA0Hash, and SHA1Hash. Definition at line 41 of file shashbase.cc. References length. Referenced by test_hash().

void SecureHashBase::final (   )  [virtual]

Do the final computing of the hash value (padding...). This needs to be done before querying the has value using GetHash(). Reimplemented in CRC32Hash, RMD160Hash, SHA0Hash, and SHA1Hash. Definition at line 47 of file shashbase.cc. Referenced by test_hash().

void SecureHashBase::GetHash (  char *  buf  )  const [virtual]

Query the (current) hash value /message digest. Should call final() before doing this; otherwise there may be some not-yet-processed input bytes pending. Make sure that your buffer can hold enough (hash_size) bytes. buf does not have to be aligned. Reimplemented in CRC32Hash, RMD160Hash, SHA0Hash, and SHA1Hash. Definition at line 52 of file shashbase.cc. Referenced by test_hash().

virtual const Parameters* SecureHashBase::GetPar (   )  const [inline, virtual]

Returns a pointer to the (normally static) parameters of this hash algorithm. The returned pointer may only be used in read-only manner. It may point to memory allocated by the hash class as the pointer may not be used after the class was destroyed. Reimplemented in CRC32Hash, RMD160Hash, SHA0Hash, and SHA1Hash. Definition at line 90 of file shashbase.h. References par. Referenced by test_hash().

void SecureHashBase::operator= (  const SecureHashBase &   )  [private]

void SecureHashBase::reset (   )  [virtual]

Reset the hash; delete the current hash value (as returned by GetHash()). Reimplemented in CRC32Hash, RMD160Hash, SHA0Hash, and SHA1Hash. Definition at line 35 of file shashbase.cc. References length. Referenced by test_hash().

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Member Data Documentation

uint64 SecureHashBase::length [protected]

length of hashed data in BYTES. Definition at line 69 of file shashbase.h. Referenced by FedBytes(), feed(), reset(), and SecureHashBase().

const SecureHashBase::Parameters SecureHashBase::par [static]

Initial value: { INIT_FIELD(hash_size) 1, INIT_FIELD(block_size) 1, INIT_FIELD(hash_ID) 0x0000, INIT_FIELD(name) "null" } Parameters of the hash algo; every derived class must provide its own _static_ parameter description. Reimplemented in CRC32Hash, RMD160Hash, SHA0Hash, and SHA1Hash. Definition at line 20 of file shashbase.cc. Referenced by GetPar().

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

• /ray/src/lib/crypto/shashbase.h
• /ray/src/lib/crypto/shashbase.cc

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