SAFER::Dec Class Reference

SAFER block cipher decryption operation. More...

`#include <safer.h>`

Inheritance diagram for SAFER::Dec:

## Public Member Functions

void | ProcessAndXorBlock (const byte *inBlock, const byte *xorBlock, byte *outBlock) const
| Encrypt or decrypt a block.
Public Member Functions inherited from SAFER::Base
unsigned int | OptimalDataAlignment () const
| Provides input and output data alignment for optimal performance.
void | UncheckedSetKey (const byte *userkey, unsigned int length, const NameValuePairs &params)
| Sets the key for this object without performing parameter validation.
Public Member Functions inherited from SimpleKeyingInterface
virtual size_t | MinKeyLength () const =0
| Returns smallest valid key length.
virtual size_t | MaxKeyLength () const =0
| Returns largest valid key length.
virtual size_t | DefaultKeyLength () const =0
| Returns default key length.
virtual size_t | GetValidKeyLength (size_t keylength) const =0
| Returns a valid key length for the algorithm.
virtual bool | IsValidKeyLength (size_t keylength) const
| Returns whether keylength is a valid key length.
virtual void | SetKey (const byte *key, size_t length, const NameValuePairs &params=g_nullNameValuePairs)
| Sets or reset the key of this object.
void | SetKeyWithRounds (const byte *key, size_t length, int rounds)
| Sets or reset the key of this object.
void | SetKeyWithIV (const byte *key, size_t length, const byte *iv, size_t ivLength)
| Sets or reset the key of this object.
void | SetKeyWithIV (const byte *key, size_t length, const byte *iv)
| Sets or reset the key of this object.
virtual IV_Requirement | IVRequirement () const =0
| Minimal requirement for secure IVs.
bool | IsResynchronizable () const
| Determines if the object can be resynchronized.
bool | CanUseRandomIVs () const
| Determines if the object can use random IVs.
bool | CanUsePredictableIVs () const
| Determines if the object can use random but possibly predictable IVs.
bool | CanUseStructuredIVs () const
| Determines if the object can use structured IVs.
virtual unsigned int | IVSize () const
| Returns length of the IV accepted by this object.
unsigned int | DefaultIVLength () const
| Provides the default size of an IV.
virtual unsigned int | MinIVLength () const
| Provides the minimum size of an IV.
virtual unsigned int | MaxIVLength () const
| Provides the maximum size of an IV.
virtual void | Resynchronize (const byte *iv, int ivLength=-1)
| Resynchronize with an IV.
virtual void | GetNextIV (RandomNumberGenerator &rng, byte *iv)
| Retrieves a secure IV for the next message.
Public Member Functions inherited from BlockTransformation
void | ProcessBlock (const byte *inBlock, byte *outBlock) const
| Encrypt or decrypt a block.
void | ProcessBlock (byte *inoutBlock) const
| Encrypt or decrypt a block in place.
virtual unsigned int | BlockSize () const =0
| Provides the block size of the cipher.
virtual bool | IsPermutation () const
| Determines if the transformation is a permutation.
virtual bool | IsForwardTransformation () const =0
| Determines if the cipher is being operated in its forward direction.
virtual unsigned int | OptimalNumberOfParallelBlocks () const
| Determines the number of blocks that can be processed in parallel.
virtual size_t | AdvancedProcessBlocks (const byte *inBlocks, const byte *xorBlocks, byte *outBlocks, size_t length, word32 flags) const
| Encrypt and xor multiple blocks using additional flags.
CipherDir | GetCipherDirection () const
| Provides the direction of the cipher.
Public Member Functions inherited from Algorithm
| Algorithm (bool checkSelfTestStatus=true)
| Interface for all crypto algorithms.
virtual std::string | AlgorithmName () const
| Provides the name of this algorithm.
virtual std::string | AlgorithmProvider () const
| Retrieve the provider of this algorithm.
Public Member Functions inherited from Clonable
virtual Clonable * | Clone () const
| Copies this object.

## 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...
Public Types inherited from BlockTransformation
enum | FlagsForAdvancedProcessBlocks { BT_InBlockIsCounter =1 , BT_DontIncrementInOutPointers =2 , BT_XorInput =4 , BT_ReverseDirection =8 , BT_AllowParallel =16 }
| Bit flags that control AdvancedProcessBlocks() behavior. More...

## Detailed Description

SAFER block cipher decryption operation.

Definition at line 41 of file safer.h.

## Member Function Documentation

## ProcessAndXorBlock()

void SAFER::Dec::ProcessAndXorBlock | ( | const byte * | inBlock,
|  | const byte * | xorBlock,
|  | byte * | outBlock ) const

virtual

Encrypt or decrypt a block.

Parameters

  inBlock | the input message before processing
  outBlock | the output message after processing
  xorBlock | an optional XOR mask

ProcessAndXorBlock encrypts or decrypts inBlock, xor with xorBlock, and write to outBlock.

The size of the block is determined by the block cipher and its documentation. Use BLOCKSIZE at compile time, or BlockSize() at runtime.

Note
  The message can be transformed in-place, or the buffers must not overlap

See also
  FixedBlockSize, BlockCipherFinal from seckey.h and BlockSize()

Implements BlockTransformation.

Definition at line 131 of file safer.cpp.

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

- safer.h
- safer.cpp