aes.hpp File Reference

AES/CMAC helpers. More...

#include <cstddef>
#include <cstdint>

Go to the source code of this file.

Namespaces
namespace	m5
	Top level namespace of M5stack.

Functions
bool	m5::nfc::crypto::aes_ecb_encrypt (uint8_t out[16], const uint8_t key[16], const uint8_t in[16])
	AES-128 ECB encryption of a single 16-byte block.
bool	m5::nfc::crypto::aes_cbc_crypt (uint8_t *out, const uint8_t key[16], const uint8_t iv_in[16], const uint8_t *in, size_t len, bool encrypt)
	AES-128 CBC encrypt or decrypt.
bool	m5::nfc::crypto::cmac_subkeys (uint8_t k1[16], uint8_t k2[16], const uint8_t key[16])
	Generate AES-CMAC subkeys K1 and K2.
bool	m5::nfc::crypto::cmac_aes_128 (uint8_t out[16], const uint8_t key[16], const uint8_t *msg, size_t msg_len)
	Calculate AES-CMAC (RFC 4493)

Detailed Description

AES/CMAC helpers.

Function Documentation

aes_cbc_crypt()

bool m5::nfc::crypto::aes_cbc_crypt	(	uint8_t *	out,
		const uint8_t	key[16],
		const uint8_t	iv_in[16],
		const uint8_t *	in,
		size_t	len,
		bool	encrypt )

AES-128 CBC encrypt or decrypt.

Parameters

[out]	out	Output buffer (same size as in)
	key	AES-128 key (16 bytes)
	iv_in	Initialization vector (16 bytes)
	in	Input buffer
	len	Input buffer length (must be multiple of 16)
	encrypt	True for encrypt, false for decrypt

Returns

True if successful

aes_ecb_encrypt()

bool m5::nfc::crypto::aes_ecb_encrypt	(	uint8_t	out[16],
		const uint8_t	key[16],
		const uint8_t	in[16] )

AES-128 ECB encryption of a single 16-byte block.

Parameters

[out]	out	Encrypted output (16 bytes)
	key	AES-128 key (16 bytes)
	in	Plaintext input (16 bytes)

Returns

True if successful

cmac_aes_128()

bool m5::nfc::crypto::cmac_aes_128	(	uint8_t	out[16],
		const uint8_t	key[16],
		const uint8_t *	msg,
		size_t	msg_len )

Calculate AES-CMAC (RFC 4493)

Parameters

[out]	out	CMAC output (16 bytes)
	key	AES-128 key (16 bytes)
	msg	Message buffer
	msg_len	Message length

Returns

True if successful

cmac_subkeys()

bool m5::nfc::crypto::cmac_subkeys	(	uint8_t	k1[16],
		uint8_t	k2[16],
		const uint8_t	key[16] )

Generate AES-CMAC subkeys K1 and K2.

Parameters

[out]	k1	Subkey K1 (16 bytes)
[out]	k2	Subkey K2 (16 bytes)
	key	AES-128 key (16 bytes)

Returns

True if successful