Class type for CBC decryption implementations. More...

Data Fields
size_t	context_size
	Size (in bytes) of the context structure appropriate for containing subkeys. More...

unsigned	block_size
	Size of individual blocks (in bytes). More...

unsigned	log_block_size
	Base-2 logarithm of the size of individual blocks, expressed in bytes. More...

void(*	init )(const br_block_cbcdec_class *ctx, const void key, size_t key_len)
	Initialisation function. More...

void(*	run )(const br_block_cbcdec_class const ctx, void iv, void data, size_t len)
	Run the CBC decryption. More...

Detailed Description

Class type for CBC decryption implementations.

A br_block_cbcdec_class instance points to the functions implementing a specific block cipher, when used in CBC mode for decrypting data.

Field Documentation

◆ block_size

unsigned br_block_cbcdec_class::block_size

Size of individual blocks (in bytes).

◆ context_size

size_t br_block_cbcdec_class::context_size

Size (in bytes) of the context structure appropriate for containing subkeys.

◆ init

void(* br_block_cbcdec_class::init) (const br_block_cbcdec_class **ctx, const void *key, size_t key_len)

Initialisation function.

This function sets the vtable field in the context structure. The key length MUST be one of the key lengths supported by the implementation.

Parameters

ctx	context structure to initialise.
key	secret key.
key_len	key length (in bytes).

◆ log_block_size

unsigned br_block_cbcdec_class::log_block_size

Base-2 logarithm of the size of individual blocks, expressed in bytes.

◆ run

void(* br_block_cbcdec_class::run) (const br_block_cbcdec_class *const *ctx, void *iv, void *data, size_t len)

Run the CBC decryption.

The iv parameter points to the IV for this run; it is updated with a copy of the last encrypted block. The data is decrypted "in place"; its length (len) MUST be a multiple of the block size.