cipher.c File Reference

CycloneBOOT Encryption & Decryption handling. More...

#include "cipher.h"
#include "cipher_modes/cbc.h"
#include "debug.h"
#include "update/update.h"

Macros
#define	TRACE_LEVEL   CBOOT_TRACE_LEVEL

Functions
cboot_error_t	cipherInit (CipherEngine *engine, const CipherAlgo *algo, CipherMode mode, const uint8_t *key, size_t keyLen)
	Initialize cipher engine context.
cboot_error_t	cipherSetIv (CipherEngine *engine, uint8_t *iv, size_t ivLen)
	Set cipher initialization vector.
cboot_error_t	cipherEncryptData (CipherEngine *engine, uint8_t *data, size_t length)
	Encrypt given data using cipher engine.
cboot_error_t	cipherDecryptData (CipherEngine *engine, uint8_t *data, size_t length)
	Decrypt given encrypted data using cipher engine.
__weak_func cboot_error_t	cipherGenerateIv (uint8_t *iv, size_t ivLen)
	Generate the initialization vector of an image about to be encrypted. The default implementation generates nothing, so that a build without a source of randomness refuses to encrypt rather than reusing a fixed vector. Override it with the entropy source of the platform, for example its TRNG. The vector is stored with the image, so it needs to differ between images, not to be secret.
cboot_error_t	cipherCheckMagicNumberCrc (uint32_t magicNumberCrc, bool_t *magicNumberIsValid)
cboot_error_t	cipherComputeMagicNumberCrc (uint32_t *magicNumberCrc)

Detailed Description

CycloneBOOT Encryption & Decryption handling.

License

SPDX-License-Identifier: GPL-2.0-or-later

Copyright (C) 2021-2026 Oryx Embedded SARL. All rights reserved.

This file is part of CycloneBOOT Open.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

Author

Oryx Embedded SARL (www.oryx-embedded.com)

Version

2.6.6

Function Documentation

cipherCheckMagicNumberCrc()

cboot_error_t cipherCheckMagicNumberCrc	(	uint32_t	magicNumberCrc,
		bool_t *	magicNumberIsValid
	)

Parameters

magicNumberCrc
keyIsValid

Returns

cboot_error_t

cipherComputeMagicNumberCrc()

cboot_error_t cipherComputeMagicNumberCrc

(

uint32_t *

magicNumberCrc

)

Parameters

magicNumberCrc

Returns

cboot_error_t

cipherDecryptData()

cboot_error_t cipherDecryptData	(	CipherEngine *	engine,
		uint8_t *	data,
		size_t	length
	)

Decrypt given encrypted data using cipher engine.

Parameters

[in]	engine	Pointer to the cipher Engine context
[in,out]	data	Buffer that initially contains encrypted data and then will hold plaintext data resulting for decryption
[in]	length	Length of the plaintext data buffer

Returns

Error code

cipherEncryptData()

cboot_error_t cipherEncryptData	(	CipherEngine *	engine,
		uint8_t *	data,
		size_t	length
	)

Encrypt given data using cipher engine.

Parameters

[in]	engine	Pointer to the cipher Engine context
[in,out]	data	Buffer that initially contains plaintext data and then will hold ciphertext data resulting from encryption
[in]	length	Length of the plaintext data buffer

Returns

Error code

cipherGenerateIv()

__weak_func cboot_error_t cipherGenerateIv	(	uint8_t *	iv,
		size_t	ivLen
	)

Generate the initialization vector of an image about to be encrypted. The default implementation generates nothing, so that a build without a source of randomness refuses to encrypt rather than reusing a fixed vector. Override it with the entropy source of the platform, for example its TRNG. The vector is stored with the image, so it needs to differ between images, not to be secret.

Parameters

[out]	iv	Buffer receiving the initialization vector
[in]	ivLen	Length of the initialization vector, in bytes

Returns

Status code

cipherInit()

cboot_error_t cipherInit	(	CipherEngine *	engine,
		const CipherAlgo *	algo,
		CipherMode	mode,
		const uint8_t *	key,
		size_t	keyLen
	)

Initialize cipher engine context.

Parameters

[in]	engine	Pointer to the cipher Engine context to initialize
[in]	algo	Cipher algorithm to be used for encryption/decryption.
[in]	mode	Cipher mode to be used with cipher algorithm
[in]	key	Pointer to the cipher key
[in]	keyLen	Length of the cipher key

Returns

Error code

cipherSetIv()

cboot_error_t cipherSetIv	(	CipherEngine *	engine,
		uint8_t *	iv,
		size_t	ivLen
	)

Set cipher initialization vector.

Parameters

[in]	engine	Pointer to the cipher Engine context
[in]	iv	Initialization vector to use for encryption
[in]	ivLen	Length of the cipher initialization vector

Returns

Error code