semf::app::AesCbc Class Reference

Abstract class for AES-CBC (Advanced Encryption Standard-Cipher Block Chaining) for symmetric encryption/decryption. More...

#include <aescbc.h>

Collaboration diagram for semf::app::AesCbc:

Public Types
enum	State : bool { Ok = true , Error = false }

Public Member Functions
virtual	~AesCbc ()=default
virtual void	setKey (const uint8_t key[], size_t size)=0
	Sets the AES key. More...
virtual void	setInitializationVector (const uint8_t initializationVector[])=0
	Sets the initialization vector. More...
virtual void	resetInitializationVector ()=0
virtual State	encrypt (const uint8_t dataIn[], uint8_t bufferOut[], size_t size)=0
	Encrypts the given data using AES-CBC algorithm. More...
virtual State	decrypt (const uint8_t dataIn[], uint8_t bufferOut[], size_t size)=0
	Performs an AES-CBC decryption on the given (encrypted) data. More...

Detailed Description

Abstract class for AES-CBC (Advanced Encryption Standard-Cipher Block Chaining) for symmetric encryption/decryption.

Warning

The format of the keys (public and private), modular and the data are in big endian format, where the MSByte is placed at the byte with the minimum address.

Definition at line 26 of file aescbc.h.

Member Enumeration Documentation

State

enum semf::app::AesCbc::State : bool

Enum for the output state of a method.

Enumerator
Ok	Successful execution of a method.
Error	Failed execution of a method.

Definition at line 30 of file aescbc.h.

Constructor & Destructor Documentation

~AesCbc()

virtual semf::app::AesCbc::~AesCbc ( )

virtualdefault

Member Function Documentation

decrypt()

virtual State semf::app::AesCbc::decrypt ( const uint8_t  dataIn[], uint8_t  bufferOut[], size_t  size  )

pure virtual

Performs an AES-CBC decryption on the given (encrypted) data.

Warning

The initialization vector has to be set before using this function.

Note

The content of the initialization vector is updated so that you can call the same function again on the next block(s) of data and get the same result as if it was encrypted in one call. This allows a "streaming" usage. If you need to retain the contents of the initialization vector, you should either save it manually or use the cipher module instead.

Parameters

dataIn	Input data which has to be decrypted.
bufferOut	Decrypted data.
size	Size of input data in bytes. It must be a multiple of the block size (16 Bytes).

Returns

State::Ok on success and State::Error on failure.

encrypt()

virtual State semf::app::AesCbc::encrypt ( const uint8_t  dataIn[], uint8_t  bufferOut[], size_t  size  )

pure virtual

Encrypts the given data using AES-CBC algorithm.

Warning

Initialization vector has to be set before using this function.

Note

The content of the initialization vector is updated so that you can call the same function again on the next block(s) of data and get the same result as if it is encrypted in one call. This allows a "streaming" usage. If you need to retain the contents of the initialization vector, you should either save it manually or use the cipher module instead.

Parameters

dataIn	Input data which has to be encrypted.
bufferOut	Encrypted data.
size	Size of input data in bytes. it must be a multiple of the block size (16 Bytes).

Returns

State::Ok on success and State::Error on failure.

resetInitializationVector()

virtual void semf::app::AesCbc::resetInitializationVector ( )

pure virtual

Resets the initialization vector.

setInitializationVector()

virtual void semf::app::AesCbc::setInitializationVector ( const uint8_t  initializationVector[] )

pure virtual

Sets the initialization vector.

Attention

The initialization vector must have the same size as the key.

Parameters

initializationVector

Pointer to the address of the initialization vector (as binary).

setKey()

virtual void semf::app::AesCbc::setKey ( const uint8_t  key[], size_t  size  )

pure virtual

Sets the AES key.

Parameters

key	Pointer to the address of the key (as binary).
size	Size of the key in bytes.

Warning

Only sizes of 128, 192, or 256 bits are supported.