AES Class Reference

Class that implements AES encryption. More...

#include <cs_AES.h>

Public Member Functions
void	init ()
	Initialize the class, reads from State. More...
cs_ret_code_t	encryptEcb (cs_data_t key, cs_data_t prefix, cs_data_t input, cs_data_t output, cs_buffer_size_t &writtenSize)
	Encrypt data with given key in ECB mode. More...
cs_ret_code_t	encryptCtr (cs_data_t key, cs_data_t nonce, cs_data_t prefix, cs_data_t input, cs_data_t output, cs_buffer_size_t &writtenSize, uint8_t blockCtr=0)
	Encrypt data with given key in CTR mode. More...
cs_ret_code_t	decryptCtr (cs_data_t key, cs_data_t nonce, cs_data_t input, cs_data_t prefix, cs_data_t output, cs_buffer_size_t &writtenSize, uint8_t blockCtr=0)
	Decrypt data with given key in CTR mode. More...

Static Public Member Functions
static AES &	getInstance ()
	Use static variant of singleton, no dynamic memory allocation. More...

Private Member Functions
	AES ()
	AES (AES const &)
void	operator= (AES const &)
cs_ret_code_t	ctr (cs_data_t key, cs_data_t nonce, cs_data_t inputPrefix, cs_data_t input, cs_data_t outputPrefix, cs_data_t output, cs_buffer_size_t &writtenSize, uint8_t blockCtr=0)
	Encrypt or decrypt data with given key in CTR mode. More...

Private Attributes
nrf_ecb_hal_data_t	_block
	Struct with key, and single block of encrypted and decypted data. More...

Detailed Description

Class that implements AES encryption.

• Block size is 16 byte.
• ECB mode has no decrypt method, as that's not hardware accelerated.
• CTR mode has both encrypt and decrypt methods.

Constructor & Destructor Documentation

AES() [1/2]

AES::AES ( )

private

AES() [2/2]

AES::AES ( AES const &  )

private

Member Function Documentation

ctr()

cs_ret_code_t AES::ctr ( cs_data_t  key, cs_data_t  nonce, cs_data_t  inputPrefix, cs_data_t  input, cs_data_t  outputPrefix, cs_data_t  output, cs_buffer_size_t &  writtenSize, uint8_t  blockCtr = 0  )

private

Encrypt or decrypt data with given key in CTR mode.

Parameters

[in]	key	Key to encrypt with.
[in]	nonce	Nonce to use for encryption.
[in]	inputPrefix	Extra data to put before the input data.
[in]	input	Input data to be encrypted.
[in]	outputPrefix	Extra data to be written to before writing to the output buffer.
[out]	output	Buffer to encrypt to. Can be the same as input, as long as: output pointer + output prefix size >= input pointer + input prefix size.
[out]	writtenSize	How many bytes are written to output.
[in]	blockCtr	Optional initial block counter.

Returns

Return code.

decryptCtr()

cs_ret_code_t AES::decryptCtr	(	cs_data_t	key,
		cs_data_t	nonce,
		cs_data_t	input,
		cs_data_t	prefix,
		cs_data_t	output,
		cs_buffer_size_t &	writtenSize,
		uint8_t	blockCtr = 0
	)

Decrypt data with given key in CTR mode.

The decrypted data is a concatenation of prefix and output.

Parameters

[in]	key	Key to encrypt with.
[in]	nonce	Nonce to use for decryption.
[in]	input	Input data to be encrypted.
[out]	prefix	Buffer to encrypt to, before the output buffer. Can be the same as input.
[out]	output	Buffer to encrypt to. Can be the same as input, as long as: output pointer <= input pointer + prefix size.
[out]	writtenSize	How many bytes are written to output.
[in]	blockCtr	Optional initial block counter.

Returns

Return code.

encryptCtr()

cs_ret_code_t AES::encryptCtr	(	cs_data_t	key,
		cs_data_t	nonce,
		cs_data_t	prefix,
		cs_data_t	input,
		cs_data_t	output,
		cs_buffer_size_t &	writtenSize,
		uint8_t	blockCtr = 0
	)

Encrypt data with given key in CTR mode.

The data that's encrypted is a concatenation of prefix and input.

Parameters

[in]	key	Key to encrypt with.
[in]	nonce	Nonce to use for encryption.
[in]	prefix	Extra data to put before the input data.
[in]	input	Input data to be encrypted.
[out]	output	Buffer to encrypt to. Can be the same as input, as long as: output pointer <= input pointer - prefix size.
[out]	writtenSize	How many bytes are written to output.
[in]	blockCtr	Optional initial block counter.

Returns

Return code.

encryptEcb()

cs_ret_code_t AES::encryptEcb	(	cs_data_t	key,
		cs_data_t	prefix,
		cs_data_t	input,
		cs_data_t	output,
		cs_buffer_size_t &	writtenSize
	)

Encrypt data with given key in ECB mode.

The data that's encrypted is a concatenation of prefix and input.

Parameters

[in]	key	Key to encrypt with.
[in]	prefix	Extra data to put before the input data. Can be skipped by passing a null pointer and data size 0.
[in]	input	Input data to be encrypted.
[out]	output	Buffer to encrypt to. Can be the same as input, as long as: output pointer >= input pointer + prefix size.
[out]	writtenSize	How many bytes are written to output.

Returns

Return code.

getInstance()

static AES & AES::getInstance ( )

inlinestatic

Use static variant of singleton, no dynamic memory allocation.

init()

void AES::init

(

)

Initialize the class, reads from State.

operator=()

void AES::operator= ( AES const &  )

private

Member Data Documentation

_block

nrf_ecb_hal_data_t AES::_block

private

Struct with key, and single block of encrypted and decypted data.

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

• source/include/encryption/cs_AES.h