zephyr/subsys/bluetooth/host/keys.h

229 lines
6.9 KiB
C

/* keys.h - Bluetooth key handling */
/*
* Copyright (c) 2015-2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
/** @cond INTERNAL_HIDDEN */
enum bt_keys_type {
BT_KEYS_PERIPH_LTK = BIT(0),
BT_KEYS_IRK = BIT(1),
BT_KEYS_LTK = BIT(2),
BT_KEYS_LOCAL_CSRK = BIT(3),
BT_KEYS_REMOTE_CSRK = BIT(4),
BT_KEYS_LTK_P256 = BIT(5),
BT_KEYS_ALL = (BT_KEYS_PERIPH_LTK | BT_KEYS_IRK |
BT_KEYS_LTK | BT_KEYS_LOCAL_CSRK |
BT_KEYS_REMOTE_CSRK | BT_KEYS_LTK_P256),
};
enum {
BT_KEYS_ID_PENDING_ADD = BIT(0),
BT_KEYS_ID_PENDING_DEL = BIT(1),
BT_KEYS_ID_ADDED = BIT(2),
};
enum {
BT_KEYS_AUTHENTICATED = BIT(0),
BT_KEYS_DEBUG = BIT(1),
/* Bit 2 and 3 might accidentally exist in old stored keys */
BT_KEYS_SC = BIT(4),
BT_KEYS_OOB = BIT(5),
};
struct bt_ltk {
uint8_t rand[8];
uint8_t ediv[2];
uint8_t val[16];
};
struct bt_irk {
uint8_t val[16];
/* Cache for `bt_keys_find_irk`. Not reliable as "current RPA"! */
bt_addr_t rpa;
};
static inline bool bt_irk_eq(struct bt_irk const *a, struct bt_irk const *b)
{
return (memcmp(a->val, b->val, sizeof(a->val)) == 0);
}
struct bt_csrk {
uint8_t val[16];
uint32_t cnt;
};
struct bt_keys {
uint8_t id;
bt_addr_le_t addr;
uint8_t state;
uint8_t storage_start[0] __aligned(sizeof(void *));
uint8_t enc_size;
uint8_t flags;
uint16_t keys;
struct bt_ltk ltk;
struct bt_irk irk;
#if defined(CONFIG_BT_SIGNING)
struct bt_csrk local_csrk;
struct bt_csrk remote_csrk;
#endif /* BT_SIGNING */
#if !defined(CONFIG_BT_SMP_SC_PAIR_ONLY)
struct bt_ltk periph_ltk;
#endif /* CONFIG_BT_SMP_SC_PAIR_ONLY */
#if (defined(CONFIG_BT_KEYS_OVERWRITE_OLDEST))
uint32_t aging_counter;
#endif /* CONFIG_BT_KEYS_OVERWRITE_OLDEST */
};
#define BT_KEYS_STORAGE_LEN (sizeof(struct bt_keys) - \
offsetof(struct bt_keys, storage_start))
/**
* @brief Get a call through the callback for each key with the same type
*
* @param type Key type.
* @param func Callback function to be called when a matched record is found.
* @param data User data to be passed to the callback function.
*/
void bt_keys_foreach_type(enum bt_keys_type type, void (*func)(struct bt_keys *keys, void *data),
void *data);
/**
* @brief Get the key slot reference for an ID and address pair.
*
* If the pair already exists in the keys pool, no new reference is reserved
* and the same reference is returned directly.
* Otherwise try to reserve one for the new ID and address pair if there is
* a room for the new pair.
*
* @note If 'CONFIG_BT_KEYS_OVERWRITE_OLDEST' is defined and the keys pool is full,
* the function will try to find the oldest key that isn't in use with a connection.
* If a key with matched criteria is found, it will be overwritten with the new one.
*
* @param id Key identifier.
* @param addr Destination address.
*
* @return A valid reference pointer to the key slot if process succeeded.
* Otherwise, a NULL value is returned.
*/
struct bt_keys *bt_keys_get_addr(uint8_t id, const bt_addr_le_t *addr);
/**
* @brief Get the key slot reference for an ID and address pair with a certain type.
*
* If the pair already exists in the keys pool, no new reference is reserved
* and the same reference is returned directly.
* Otherwise try to reserve one for the new ID and address pair if there is
* a room for the new pair and set the type.
*
* @param type Key type.
* @param id Key identifier.
* @param addr Destination address.
*
* @return A valid reference pointer to the key slot if process succeeded.
* Otherwise, a NULL value is returned.
*/
struct bt_keys *bt_keys_get_type(enum bt_keys_type type, uint8_t id, const bt_addr_le_t *addr);
/**
* @brief Find key identified by type, ID and address
*
* @param type Key type.
* @param id Key identifier.
* @param addr Destination address.
*
* @return A valid reference pointer to the key slot if it exists.
* Otherwise, a NULL value is returned.
*/
struct bt_keys *bt_keys_find(enum bt_keys_type type, uint8_t id, const bt_addr_le_t *addr);
/**
* @brief Find key reference by trying to resolve an RPA using IRK
*
* @param id Key identifier.
* @param addr Destination address.
* @return A valid reference pointer to the key slot on success.
* Otherwise, a NULL value is returned.
*/
struct bt_keys *bt_keys_find_irk(uint8_t id, const bt_addr_le_t *addr);
/**
* @brief Find a key by ID and address
*
* @param id Key identifier.
* @param addr Destination address.
* @return A valid reference pointer to the key slot if it exists.
* Otherwise, a NULL value is returned.
*/
struct bt_keys *bt_keys_find_addr(uint8_t id, const bt_addr_le_t *addr);
/**
* @brief Add a type to a key
*
* @param keys Key reference.
* @param type Key type to be added.
*/
void bt_keys_add_type(struct bt_keys *keys, enum bt_keys_type type);
/**
* @brief Clear a key contents
*
* @param keys Key reference to be cleared.
*/
void bt_keys_clear(struct bt_keys *keys);
#if defined(CONFIG_BT_SETTINGS)
/**
* @brief Store key to persistent memory
*
* @param keys Key reference.
* @return 0 on success, non-zero error code otherwise
*/
int bt_keys_store(struct bt_keys *keys);
#else
static inline int bt_keys_store(struct bt_keys *keys)
{
return 0;
}
#endif
enum {
BT_LINK_KEY_AUTHENTICATED = BIT(0),
BT_LINK_KEY_DEBUG = BIT(1),
BT_LINK_KEY_SC = BIT(2),
};
struct bt_keys_link_key {
bt_addr_t addr;
uint8_t storage_start[0] __aligned(sizeof(void *));
uint8_t flags;
uint8_t val[16];
#if (defined(CONFIG_BT_KEYS_OVERWRITE_OLDEST))
uint32_t aging_counter;
#endif /* CONFIG_BT_KEYS_OVERWRITE_OLDEST */
};
#define BT_KEYS_LINK_KEY_STORAGE_LEN (sizeof(struct bt_keys_link_key) - \
offsetof(struct bt_keys_link_key, storage_start))
struct bt_keys_link_key *bt_keys_get_link_key(const bt_addr_t *addr);
struct bt_keys_link_key *bt_keys_find_link_key(const bt_addr_t *addr);
void bt_keys_link_key_clear(struct bt_keys_link_key *link_key);
void bt_keys_link_key_clear_addr(const bt_addr_t *addr);
void bt_keys_link_key_store(struct bt_keys_link_key *link_key);
/* This function is used to signal that the key has been used for paring */
/* It updates the aging counter and saves it to flash if configuration option */
/* BT_KEYS_SAVE_AGING_COUNTER_ON_PAIRING is enabled */
void bt_keys_update_usage(uint8_t id, const bt_addr_le_t *addr);
void bt_keys_link_key_update_usage(const bt_addr_t *addr);
void bt_keys_show_sniffer_info(struct bt_keys *keys, void *data);
/** @endcond */