Cryptography

Cryptography. More...

Functions
int	bt_rand (void *buf, size_t len)
	Generate random data. More...
int	bt_encrypt_le (const uint8_t key[16], const uint8_t plaintext[16], uint8_t enc_data[16])
	AES encrypt little-endian data. More...
int	bt_encrypt_be (const uint8_t key[16], const uint8_t plaintext[16], uint8_t enc_data[16])
	AES encrypt big-endian data. More...
int	bt_ccm_decrypt (const uint8_t key[16], uint8_t nonce[13], const uint8_t *enc_data, size_t len, const uint8_t *aad, size_t aad_len, uint8_t *plaintext, size_t mic_size)
	Decrypt big-endian data with AES-CCM. More...
int	bt_ccm_encrypt (const uint8_t key[16], uint8_t nonce[13], const uint8_t *plaintext, size_t len, const uint8_t *aad, size_t aad_len, uint8_t *enc_data, size_t mic_size)
	Encrypt big-endian data with AES-CCM. More...

Detailed Description

Cryptography.

Function Documentation

bt_ccm_decrypt()

int bt_ccm_decrypt	(	const uint8_t	key[16],
		uint8_t	nonce[13],
		const uint8_t *	enc_data,
		size_t	len,
		const uint8_t *	aad,
		size_t	aad_len,
		uint8_t *	plaintext,
		size_t	mic_size
	)

#include <include/bluetooth/crypto.h>

Decrypt big-endian data with AES-CCM.

Decrypts and authorizes enc_data with AES-CCM, as described in https://tools.ietf.org/html/rfc3610.

Assumes that the MIC follows directly after the encrypted data.

Parameters

key	128 bit MS byte first key
nonce	13 byte MS byte first nonce
enc_data	Encrypted data
len	Length of the encrypted data
aad	Additional input data
aad_len	Additional input data length
plaintext	Plaintext buffer to place result in
mic_size	Size of the trailing MIC (in bytes)

Return values

0	Successfully decrypted the data.
-EINVAL	Invalid parameters.
-EBADMSG	Authentication failed.

bt_ccm_encrypt()

int bt_ccm_encrypt	(	const uint8_t	key[16],
		uint8_t	nonce[13],
		const uint8_t *	plaintext,
		size_t	len,
		const uint8_t *	aad,
		size_t	aad_len,
		uint8_t *	enc_data,
		size_t	mic_size
	)

#include <include/bluetooth/crypto.h>

Encrypt big-endian data with AES-CCM.

Encrypts and generates a MIC from plaintext with AES-CCM, as described in https://tools.ietf.org/html/rfc3610.

Places the MIC directly after the encrypted data.

Parameters

key	128 bit MS byte first key
nonce	13 byte MS byte first nonce
plaintext	Plaintext buffer to encrypt
len	Length of the encrypted data
aad	Additional input data
aad_len	Additional input data length
enc_data	Buffer to place encrypted data in
mic_size	Size of the trailing MIC (in bytes)

Return values

0	Successfully encrypted the data.
-EINVAL	Invalid parameters.

bt_encrypt_be()

int bt_encrypt_be	(	const uint8_t	key[16],
		const uint8_t	plaintext[16],
		uint8_t	enc_data[16]
	)

#include <include/bluetooth/crypto.h>

AES encrypt big-endian data.

An AES encrypt helper is used to request the Bluetooth controller's own hardware to encrypt the plaintext using the key and returns the encrypted data.

Parameters

key	128 bit MS byte first key for the encryption of the plaintext
plaintext	128 bit MS byte first plaintext data block to be encrypted
enc_data	128 bit MS byte first encrypted data block

Returns

Zero on success or error code otherwise.

bt_encrypt_le()

int bt_encrypt_le	(	const uint8_t	key[16],
		const uint8_t	plaintext[16],
		uint8_t	enc_data[16]
	)

#include <include/bluetooth/crypto.h>

AES encrypt little-endian data.

An AES encrypt helper is used to request the Bluetooth controller's own hardware to encrypt the plaintext using the key and returns the encrypted data.

Parameters

key	128 bit LS byte first key for the encryption of the plaintext
plaintext	128 bit LS byte first plaintext data block to be encrypted
enc_data	128 bit LS byte first encrypted data block

Returns

Zero on success or error code otherwise.

bt_rand()

int bt_rand	(	void *	buf,
		size_t	len
	)

#include <include/bluetooth/crypto.h>

Generate random data.

A random number generation helper which utilizes the Bluetooth controller's own RNG.

Parameters

buf	Buffer to insert the random data
len	Length of random data to generate

Returns

Zero on success or error code otherwise, positive in case of protocol error or negative (POSIX) in case of stack internal error