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SimpleKeyingInterface Class Reference

#include <cryptlib.h>

Inheritance diagram for SimpleKeyingInterface:

BlockCipher MessageAuthenticationCode SimpleKeyedTransformation< T > SymmetricCipher MessageAuthenticationCodeTemplate< BASE > MessageAuthenticationCodeTemplate< CBC_MAC_Base< T > > MessageAuthenticationCodeTemplate< DMAC_Base< T > > MessageAuthenticationCodeTemplate< HMAC_Base< T > > MessageAuthenticationCodeTemplate< PanamaMAC_Base< B > > MessageAuthenticationCodeTemplate< XMACC_Base< T > > PanamaMAC_Base< B > ARC4_Base List of all members.

Detailed Description

keying interface for crypto algorithms that take byte strings as keys

Definition at line 331 of file cryptlib.h.

Public Types

enum  IV_Requirement {
  STRUCTURED_IV = 0, RANDOM_IV, UNPREDICTABLE_RANDOM_IV, INTERNALLY_GENERATED_IV,
  NOT_RESYNCHRONIZABLE
}

Public Member Functions

virtual unsigned int MinKeyLength () const =0
 returns smallest valid key length in bytes */

virtual unsigned int MaxKeyLength () const =0
 returns largest valid key length in bytes */

virtual unsigned int DefaultKeyLength () const =0
 returns default (recommended) key length in bytes */

virtual unsigned int GetValidKeyLength (unsigned int n) const =0
 returns the smallest valid key length in bytes that is >= min(n, GetMaxKeyLength())

virtual bool IsValidKeyLength (unsigned int n) const
 returns whether n is a valid key length

virtual void SetKey (const byte *key, unsigned int length, const NameValuePairs &params=g_nullNameValuePairs)=0
 set or reset the key of this object

void SetKeyWithRounds (const byte *key, unsigned int length, int rounds)
 calls SetKey() with an NameValuePairs object that just specifies "Rounds"

void SetKeyWithIV (const byte *key, unsigned int length, const byte *iv)
 calls SetKey() with an NameValuePairs object that just specifies "IV"

virtual IV_Requirement IVRequirement () const =0
 returns the minimal requirement for secure IVs

bool IsResynchronizable () const
 returns whether this object can be resynchronized (i.e. supports initialization vectors)

bool CanUseRandomIVs () const
 returns whether this object can use random IVs (in addition to ones returned by GetNextIV)

bool CanUsePredictableIVs () const
 returns whether this object can use random but possibly predictable IVs (in addition to ones returned by GetNextIV)

bool CanUseStructuredIVs () const
 returns whether this object can use structured IVs, for example a counter (in addition to ones returned by GetNextIV)

virtual unsigned int IVSize () const
 returns size of IVs used by this object

virtual void Resynchronize (const byte *IV)
 resynchronize with an IV

virtual void GetNextIV (byte *IV)
 get a secure IV for the next message


Protected Member Functions

void ThrowIfInvalidKeyLength (const Algorithm &algorithm, unsigned int length)
void AssertValidKeyLength (unsigned int length) const


Member Function Documentation

virtual void SimpleKeyingInterface::SetKey const byte *  key,
unsigned int  length,
const NameValuePairs params = g_nullNameValuePairs
[pure virtual]
 

set or reset the key of this object

Parameters:
params is used to specify Rounds, BlockSize, etc

Implemented in MessageAuthenticationCodeTemplate< BASE >, MessageAuthenticationCodeTemplate< CBC_MAC_Base< T > >, MessageAuthenticationCodeTemplate< HMAC_Base< T > >, MessageAuthenticationCodeTemplate< XMACC_Base< T > >, MessageAuthenticationCodeTemplate< DMAC_Base< T > >, and MessageAuthenticationCodeTemplate< PanamaMAC_Base< B > >.

Referenced by SetKeyWithIV(), and SetKeyWithRounds().

bool SimpleKeyingInterface::IsResynchronizable  )  const [inline]
 

returns whether this object can be resynchronized (i.e. supports initialization vectors)

If this function returns true, and no IV is passed to SetKey() and CanUseStructuredIVs()==true, an IV of all 0's will be assumed.

Definition at line 364 of file cryptlib.h.

References IVRequirement().

virtual void SimpleKeyingInterface::GetNextIV byte *  IV  )  [inline, virtual]
 

get a secure IV for the next message

This method should be called after you finish encrypting one message and are ready to start the next one. After calling it, you must call SetKey() or Resynchronize() before using this object again. This method is not implemented on decryption objects.

Definition at line 380 of file cryptlib.h.

References GetNextIV().

Referenced by GetNextIV().


The documentation for this class was generated from the following files:
Generated on Wed Jul 28 08:07:16 2004 for Crypto++ by doxygen 1.3.7