zephyr/subsys/bluetooth/host/ecc.h

89 lines
2.7 KiB
C

/* ecc.h - ECDH helpers */
/*
* Copyright (c) 2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
/** Key size used in Bluetooth's ECC domain. */
#define BT_ECC_KEY_SIZE 32
/** Length of a Bluetooth ECC public key coordinate. */
#define BT_PUB_KEY_COORD_LEN (BT_ECC_KEY_SIZE)
/** Length of a Bluetooth ECC public key. */
#define BT_PUB_KEY_LEN (2 * (BT_PUB_KEY_COORD_LEN))
/** Length of a Bluetooth ECC private key. */
#define BT_PRIV_KEY_LEN (BT_ECC_KEY_SIZE)
/** Length of a Bluetooth Diffie-Hellman key. */
#define BT_DH_KEY_LEN (BT_ECC_KEY_SIZE)
/* @brief Container for public key callback */
struct bt_pub_key_cb {
/** @brief Callback type for Public Key generation.
*
* Used to notify of the local public key or that the local key is not
* available (either because of a failure to read it or because it is
* being regenerated).
*
* @param key The local public key, or NULL in case of no key.
*/
void (*func)(const uint8_t key[BT_PUB_KEY_LEN]);
/* Internal */
sys_snode_t node;
};
/* @brief Check if public key is equal to the debug public key.
*
* Compare the Public key to the Bluetooth specification defined debug public
* key.
*
* @param pub_key The public key to compare.
*
* @return True if the public key is the debug public key.
*/
bool bt_pub_key_is_debug(uint8_t *pub_key);
/* @brief Generate a new Public Key.
*
* Generate a new ECC Public Key. Provided cb must persists until callback
* is called. Callee adds the callback structure to a linked list. Registering
* multiple callbacks requires multiple calls to bt_pub_key_gen() and separate
* callback structures. This method cannot be called directly from result
* callback. After calling all the registered callbacks the linked list
* is cleared.
*
* @param cb Callback to notify the new key.
*
* @return Zero on success or negative error code otherwise
*/
int bt_pub_key_gen(struct bt_pub_key_cb *cb);
/* @brief Get the current Public Key.
*
* Get the current ECC Public Key.
*
* @return Current key, or NULL if not available.
*/
const uint8_t *bt_pub_key_get(void);
/* @typedef bt_dh_key_cb_t
* @brief Callback type for DH Key calculation.
*
* Used to notify of the calculated DH Key.
*
* @param key The DH Key, or NULL in case of failure.
*/
typedef void (*bt_dh_key_cb_t)(const uint8_t key[BT_DH_KEY_LEN]);
/* @brief Calculate a DH Key from a remote Public Key.
*
* Calculate a DH Key from the remote Public Key.
*
* @param remote_pk Remote Public Key.
* @param cb Callback to notify the calculated key.
*
* @return Zero on success or negative error code otherwise
*/
int bt_dh_key_gen(const uint8_t remote_pk[BT_PUB_KEY_LEN], bt_dh_key_cb_t cb);