Arduino Cryptography Library
Public Member Functions | List of all members
OFB< T > Class Template Reference

Implementation of the Output Feedback (OFB) mode for 128-bit block ciphers. More...

#include <OFB.h>

Inheritance diagram for OFB< T >:
OFBCommon Cipher

Public Member Functions

 OFB ()
 Constructs a new OFB object for the block cipher T.
 
- Public Member Functions inherited from OFBCommon
virtual ~OFBCommon ()
 Destroys this cipher object after clearing sensitive information.
 
size_t keySize () const
 Default size of the key for this cipher, in bytes. More...
 
size_t ivSize () const
 Size of the initialization vector for this cipher, in bytes. More...
 
bool setKey (const uint8_t *key, size_t len)
 Sets the key to use for future encryption and decryption operations. More...
 
bool setIV (const uint8_t *iv, size_t len)
 Sets the initialization vector to use for future encryption and decryption operations. More...
 
void encrypt (uint8_t *output, const uint8_t *input, size_t len)
 Encrypts an input buffer and writes the ciphertext to an output buffer. More...
 
void decrypt (uint8_t *output, const uint8_t *input, size_t len)
 Decrypts an input buffer and writes the plaintext to an output buffer. More...
 
void clear ()
 Clears all security-sensitive state from this cipher. More...
 
- Public Member Functions inherited from Cipher
 Cipher ()
 Constructs a new cipher object.
 
virtual ~Cipher ()
 Destroys this cipher object. More...
 

Additional Inherited Members

- Protected Member Functions inherited from OFBCommon
 OFBCommon ()
 Constructs a new cipher in OFB mode. More...
 
void setBlockCipher (BlockCipher *cipher)
 Sets the block cipher to use for this OFB object. More...
 

Detailed Description

template<typename T>
class OFB< T >

Implementation of the Output Feedback (OFB) mode for 128-bit block ciphers.

The template parameter T must be a concrete subclass of BlockCipher indicating the specific block cipher to use. T must have a block size of 16 bytes (128 bits).

For example, the following creates a OFB object using AES192 as the underlying cipher:

ofb.setKey(key, 24);
ofb.setIV(iv, 16);
ofb.encrypt(output, input, len);
bool setIV(const uint8_t *iv, size_t len)
Sets the initialization vector to use for future encryption and decryption operations.
Definition: OFB.cpp:76
void encrypt(uint8_t *output, const uint8_t *input, size_t len)
Encrypts an input buffer and writes the ciphertext to an output buffer.
Definition: OFB.cpp:85
bool setKey(const uint8_t *key, size_t len)
Sets the key to use for future encryption and decryption operations.
Definition: OFB.cpp:66
Implementation of the Output Feedback (OFB) mode for 128-bit block ciphers.
Definition: OFB.h:57

Decryption is identical to encryption for OFB mode.

The size of the ciphertext will always be the same as the size of the plaintext.

Reference: http://en.wikipedia.org/wiki/Block_cipher_mode_of_operation

See also
CTR, CFB, CBC

Definition at line 56 of file OFB.h.


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