cbc.h File Reference

Cipher block chaining mode of operation for block ciphers. More...

Detailed Description

Cipher block chaining mode of operation for block ciphers.

Author

Freie Universitaet Berlin, Computer Systems & Telematics

Nico von Geyso nico..nosp@m.geys.nosp@m.o@fu-.nosp@m.berl.nosp@m.in.de

Definition in file cbc.h.

#include <stddef.h>
#include "crypto/ciphers.h"

Include dependency graph for cbc.h:

Go to the source code of this file.

int	cipher_encrypt_cbc (const cipher_t *cipher, uint8_t iv[16], const uint8_t *input, size_t input_len, uint8_t *output)
	Encrypt data of arbitrary length in cipher block chaining mode.
int	cipher_decrypt_cbc (const cipher_t *cipher, uint8_t iv[16], const uint8_t *input, size_t input_len, uint8_t *output)
	Decrypt encrypted data in cipher block chaining mode.

Function Documentation

cipher_decrypt_cbc()

int cipher_decrypt_cbc	(	const cipher_t *	cipher,
		uint8_t	iv[16],
		const uint8_t *	input,
		size_t	input_len,
		uint8_t *	output
	)

Decrypt encrypted data in cipher block chaining mode.

Parameters

cipher	Already initialized cipher struct
iv	16 octet initialization vector.
input	pointer to input data to decrypt
input_len	length of the input data
output	pointer to allocated memory for plaintext data. It has to be of size input_len.

Returns

<0 on error

CIPHER_ERR_INVALID_LENGTH when input_len % BLOCK_SIZE != 0

CIPHER_ERR_DEC_FAILED on internal decryption error

otherwise number of bytes decrypted

cipher_encrypt_cbc()

int cipher_encrypt_cbc	(	const cipher_t *	cipher,
		uint8_t	iv[16],
		const uint8_t *	input,
		size_t	input_len,
		uint8_t *	output
	)

Encrypt data of arbitrary length in cipher block chaining mode.

Parameters

cipher	Already initialized cipher struct
iv	16 octet initialization vector. Must never be used more than once for a given key.
input	pointer to input data to encrypt
input_len	length of the input data
output	pointer to allocated memory for encrypted data. It has to be of size data_len + BLOCK_SIZE - data_len % BLOCK_SIZE.

Returns

<0 on error

CIPHER_ERR_INVALID_LENGTH when input_len % BLOCK_SIZE != 0

CIPHER_ERR_ENC_FAILED on internal encryption error

otherwise number of input bytes that aren't consumed