API for block ciphers. More...

#include "cx_errors.h"
#include "lcx_wrappers.h"
#include "lcx_common.h"
#include "lcx_aes.h"
#include <stddef.h>

Include dependency graph for lcx_cipher.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Classes
struct	cipher_key_t

struct	cx_cipher_base_t

struct	cx_cipher_info_t

struct	cx_cipher_context_t

Macros
#define	MAX_IV_LENGTH 16

#define	MAX_BLOCK_LENGTH 16

Enumerations
enum	cx_cipher_id_t { CX_CIPHER_NONE = 0 , CX_CIPHER_AES_128 , CX_CIPHER_AES_192 , CX_CIPHER_AES_256 }

Functions
WARN_UNUSED_RESULT cx_err_t	cx_cipher_init (cx_cipher_context_t *ctx)
	Initialize a cipher context as NONE. More...

WARN_UNUSED_RESULT cx_err_t	cx_cipher_setup (cx_cipher_context_t *ctx, const cx_cipher_id_t type, uint32_t mode)
	Initialize and fill the context structure given the cipher info. More...

WARN_UNUSED_RESULT cx_err_t	cx_cipher_setkey (cx_cipher_context_t ctx, const uint8_t key, uint32_t key_bitlen, uint32_t operation)
	Set the key to use. More...

WARN_UNUSED_RESULT cx_err_t	cx_cipher_setiv (cx_cipher_context_t ctx, const uint8_t iv, size_t iv_len)
	Set the initialization vector. More...

WARN_UNUSED_RESULT cx_err_t	cx_cipher_set_padding (cx_cipher_context_t *ctx, uint32_t padding)
	Set the padding type. More...

WARN_UNUSED_RESULT cx_err_t	cx_cipher_update (cx_cipher_context_t ctx, const uint8_t input, size_t in_len, uint8_t output, size_t out_len)
	Encrypt or decrypt with the given context. More...

WARN_UNUSED_RESULT cx_err_t	cx_cipher_finish (cx_cipher_context_t ctx, uint8_t output, size_t *out_len)
	Finalize the operation. More...

WARN_UNUSED_RESULT cx_err_t	cx_cipher_enc_dec (cx_cipher_context_t ctx, const uint8_t iv, size_t iv_len, const uint8_t input, size_t in_len, uint8_t output, size_t *out_len)
	All-in-one encryption or decryption. More...

void	cx_cipher_reset (cx_cipher_context_t *ctx)

void	add_one_and_zeros_padding (uint8_t *output, size_t out_len, size_t data_len)

Detailed Description

API for block ciphers.

This file contains the functions which enable to use standard block ciphers like AES for encryption and decryption in a specific mode of operation.

Definition in file lcx_cipher.h.

Macro Definition Documentation

◆ MAX_BLOCK_LENGTH

#define MAX_BLOCK_LENGTH 16

Maximum block size in bytes

Definition at line 21 of file lcx_cipher.h.

◆ MAX_IV_LENGTH

#define MAX_IV_LENGTH 16

Maximum length of the initialization vector in bytes

Definition at line 19 of file lcx_cipher.h.

Enumeration Type Documentation

◆ cx_cipher_id_t

enum cx_cipher_id_t

Supported cipher identifiers

Enumerator
CX_CIPHER_NONE	No cipher.
CX_CIPHER_AES_128	AES with a 128-bit key.
CX_CIPHER_AES_192	AES with a 192-bit key.
CX_CIPHER_AES_256	AES with a 256-bit key.

Definition at line 36 of file lcx_cipher.h.

Function Documentation

◆ add_one_and_zeros_padding()

void add_one_and_zeros_padding	(	uint8_t *	output,
		size_t	out_len,
		size_t	data_len
	)

Definition at line 79 of file cx_cipher.c.

◆ cx_cipher_enc_dec()

WARN_UNUSED_RESULT cx_err_t cx_cipher_enc_dec	(	cx_cipher_context_t *	ctx,
		const uint8_t *	iv,
		size_t	iv_len,
		const uint8_t *	input,
		size_t	in_len,
		uint8_t *	output,
		size_t *	out_len
	)

All-in-one encryption or decryption.

This function must be called after the cipher context is initialized with cx_cipher_init and set with cx_cipher_setup. The key must be set with cx_cipher_setkey, the padding method to use must be set with cx_cipher_set_padding.

Parameters

[in]	ctx	Pointer to the context.
[in]	iv	Initialization vector: a buffer of at least iv_len bytes.
[in]	iv_len	Length of the initialization vector in bytes.
[in]	input	Input data: a buffer of at least in_len bytes.
[in]	in_len	Length of the input in bytes.
[out]	output	Output data: a buffer of at least in_len + block_size bytes.
[out]	out_len	Length of the output.

Returns

Error code:

CX_OK on success
CX_INTERNAL_ERROR
CX_INVALID_PARAMETER
CX_INVALID_PARAMETER_VALUE

Definition at line 492 of file cx_cipher.c.

◆ cx_cipher_finish()

WARN_UNUSED_RESULT cx_err_t cx_cipher_finish	(	cx_cipher_context_t *	ctx,
		uint8_t *	output,
		size_t *	out_len
	)

Finalize the operation.

This function must be called after the cipher context is initialized with cx_cipher_init and set with cx_cipher_setup. The key must be set with cx_cipher_setkey, the padding method to use must be set with cx_cipher_set_padding and the Initialization Vector must be set with cx_cipher_setiv. This function must be called after the last cx_cipher_update.

Parameters

[in]	ctx	Pointer to the context.
[out]	output	Output data: buffer of at least block_size bytes.
[out]	out_len	Length of the data written to the output.

Returns

Error code:

CX_Ok on success
CX_INTERNAL_ERROR
CX_INVALID_PARAMETER
CX_INVALID_PARAMETER_VALUE

Definition at line 411 of file cx_cipher.c.

◆ cx_cipher_init()

WARN_UNUSED_RESULT cx_err_t cx_cipher_init ( cx_cipher_context_t * ctx )

Initialize a cipher context as NONE.

This function must be called first.

Parameters

[in] ctx Pointer to the context. This must not be NULL.

Returns

Error code:

CX_OK on success
CX_INVALID_PARAMETER

Definition at line 209 of file cx_cipher.c.

◆ cx_cipher_reset()

void cx_cipher_reset ( cx_cipher_context_t * ctx )

Definition at line 516 of file cx_cipher.c.

◆ cx_cipher_set_padding()

WARN_UNUSED_RESULT cx_err_t cx_cipher_set_padding	(	cx_cipher_context_t *	ctx,
		uint32_t	padding
	)

Set the padding type.

This function must be called after the cipher context is initialized with cx_cipher_init.

Parameters

[in]	ctx	Pointer to the context.
[in]	padding	Type of padding: CX_PAD_NONE: no padding CX_PAD_ISO9797M1: pad with zeros only CX_PAD_ISO9797M2: pad with a single one and several zeros.

Returns

Error code:

CX_OK on success
CX_INVALID_PARAMETER
CX_INVALID_PARAMETER_VALUE

Definition at line 301 of file cx_cipher.c.

◆ cx_cipher_setiv()

WARN_UNUSED_RESULT cx_err_t cx_cipher_setiv	(	cx_cipher_context_t *	ctx,
		const uint8_t *	iv,
		size_t	iv_len
	)

Set the initialization vector.

This function must be called after the cipher context is initialized with cx_cipher_init.

Parameters

[in]	ctx	Pointer to the context.
[in]	iv	Initialization vector: a buffer of at least iv_len bytes.
[in]	iv_len	Length of the initialization vector in bytes.

Returns

Error code:

CX_OK on success
CX_INVALID_PARAMETER
CX_INVALID_PARAMETER_VALUE

Definition at line 276 of file cx_cipher.c.

◆ cx_cipher_setkey()

WARN_UNUSED_RESULT cx_err_t cx_cipher_setkey	(	cx_cipher_context_t *	ctx,
		const uint8_t *	key,
		uint32_t	key_bitlen,
		uint32_t	operation
	)

Set the key to use.

This function must be called after the cipher context is initialized with cx_cipher_init.

Parameters

[in]	ctx	Pointer to the context.
[in]	key	Key to use: a buffer of at least key_bitlen bits.
[in]	key_bitlen	Length of key in bits.
[in]	operation	The operation that the key will be used for: encryption or decryption.

Returns

Error code:

CX_OK on success
CX_INVALID_PARAMETER
CX_INVALID_PARAMETER_SIZE
CX_INVALID_PARAMETER_VALUE

Definition at line 253 of file cx_cipher.c.

◆ cx_cipher_setup()

WARN_UNUSED_RESULT cx_err_t cx_cipher_setup	(	cx_cipher_context_t *	ctx,
		const cx_cipher_id_t	type,
		uint32_t	mode
	)

Initialize and fill the context structure given the cipher info.

Parameters

[in]	ctx	Pointer to the context.
[in]	type	Cipher to use: CX_CIPHER_AES_128 CX_CIPHER_AES_192 CX_CIPHER_AES_256
[in]	mode	Mode of operation: ECB CBC CTR

Returns

Error code:

CX_OK on success
CX_INVALID_PARAMETER
CX_INVALID_PARAMETER_VALUE

Definition at line 218 of file cx_cipher.c.

◆ cx_cipher_update()

WARN_UNUSED_RESULT cx_err_t cx_cipher_update	(	cx_cipher_context_t *	ctx,
		const uint8_t *	input,
		size_t	in_len,
		uint8_t *	output,
		size_t *	out_len
	)

Encrypt or decrypt with the given context.

This function must be called after the cipher context is initialized with cx_cipher_init and set with cx_cipher_setup. The key must be set with cx_cipher_setkey, the padding method to use must be set with cx_cipher_set_padding and the Initialization Vector must be set with cx_cipher_setiv. One can call this function multiple times depending on the length of the data that needed to be processed.

Parameters

[in]	ctx	Pointer to the context.
[in]	input	Input data: buffer of at least in_len bytes.
[in]	in_len	Length of the input in bytes.
[out]	output	Output data: a buffer of at least in_len + block_size bytes.
[out]	out_len	Length of the data written to the output.

Returns

Error code:

CX_OK on success
CX_INTERNAL_ERROR
CX_INVALID_PARAMETER
CX_INVALID_PARAMETER_VALUE

Definition at line 324 of file cx_cipher.c.

Classes

Macros

Enumerations

Functions

Detailed Description

Macro Definition Documentation

◆ MAX_BLOCK_LENGTH

◆ MAX_IV_LENGTH

Enumeration Type Documentation

◆ cx_cipher_id_t

Function Documentation

◆ add_one_and_zeros_padding()

◆ cx_cipher_enc_dec()

◆ cx_cipher_finish()

◆ cx_cipher_init()

◆ cx_cipher_reset()

◆ cx_cipher_set_padding()

◆ cx_cipher_setiv()

◆ cx_cipher_setkey()

◆ cx_cipher_setup()

◆ cx_cipher_update()