/** @file * @brief Bluetooth connection handling */ /* * Copyright (c) 2015-2016 Intel Corporation * * SPDX-License-Identifier: Apache-2.0 */ #ifndef ZEPHYR_INCLUDE_BLUETOOTH_CONN_H_ #define ZEPHYR_INCLUDE_BLUETOOTH_CONN_H_ /** * @brief Connection management * @defgroup bt_conn Connection management * @ingroup bluetooth * @{ */ #include #include #include #include #include #ifdef __cplusplus extern "C" { #endif /** Opaque type representing a connection to a remote device */ struct bt_conn; /** Connection parameters for LE connections */ struct bt_le_conn_param { uint16_t interval_min; uint16_t interval_max; uint16_t latency; uint16_t timeout; }; /** @brief Initialize connection parameters * * @param int_min Minimum Connection Interval (N * 1.25 ms) * @param int_max Maximum Connection Interval (N * 1.25 ms) * @param lat Connection Latency * @param to Supervision Timeout (N * 10 ms) */ #define BT_LE_CONN_PARAM_INIT(int_min, int_max, lat, to) \ { \ .interval_min = (int_min), \ .interval_max = (int_max), \ .latency = (lat), \ .timeout = (to), \ } /** Helper to declare connection parameters inline * * @param int_min Minimum Connection Interval (N * 1.25 ms) * @param int_max Maximum Connection Interval (N * 1.25 ms) * @param lat Connection Latency * @param to Supervision Timeout (N * 10 ms) */ #define BT_LE_CONN_PARAM(int_min, int_max, lat, to) \ ((struct bt_le_conn_param[]) { \ BT_LE_CONN_PARAM_INIT(int_min, int_max, lat, to) \ }) /** Default LE connection parameters: * Connection Interval: 30-50 ms * Latency: 0 * Timeout: 4 s */ #define BT_LE_CONN_PARAM_DEFAULT BT_LE_CONN_PARAM(BT_GAP_INIT_CONN_INT_MIN, \ BT_GAP_INIT_CONN_INT_MAX, \ 0, 400) /** Connection PHY information for LE connections */ struct bt_conn_le_phy_info { uint8_t tx_phy; /** Connection transmit PHY */ uint8_t rx_phy; /** Connection receive PHY */ }; /** Connection PHY options */ enum { /** Convenience value when no options are specified. */ BT_CONN_LE_PHY_OPT_NONE = 0, /** LE Coded using S=2 coding preferred when transmitting. */ BT_CONN_LE_PHY_OPT_CODED_S2 = BIT(0), /** LE Coded using S=8 coding preferred when transmitting. */ BT_CONN_LE_PHY_OPT_CODED_S8 = BIT(1), }; /** Preferred PHY parameters for LE connections */ struct bt_conn_le_phy_param { uint16_t options; /** Connection PHY options. */ uint8_t pref_tx_phy; /** Bitmask of preferred transmit PHYs */ uint8_t pref_rx_phy; /** Bitmask of preferred receive PHYs */ }; /** Initialize PHY parameters * * @param _pref_tx_phy Bitmask of preferred transmit PHYs. * @param _pref_rx_phy Bitmask of preferred receive PHYs. */ #define BT_CONN_LE_PHY_PARAM_INIT(_pref_tx_phy, _pref_rx_phy) \ { \ .options = BT_CONN_LE_PHY_OPT_NONE, \ .pref_tx_phy = (_pref_tx_phy), \ .pref_rx_phy = (_pref_rx_phy), \ } /** Helper to declare PHY parameters inline * * @param _pref_tx_phy Bitmask of preferred transmit PHYs. * @param _pref_rx_phy Bitmask of preferred receive PHYs. */ #define BT_CONN_LE_PHY_PARAM(_pref_tx_phy, _pref_rx_phy) \ ((struct bt_conn_le_phy_param []) { \ BT_CONN_LE_PHY_PARAM_INIT(_pref_tx_phy, _pref_rx_phy) \ }) /** Only LE 1M PHY */ #define BT_CONN_LE_PHY_PARAM_1M BT_CONN_LE_PHY_PARAM(BT_GAP_LE_PHY_1M, \ BT_GAP_LE_PHY_1M) /** Only LE 2M PHY */ #define BT_CONN_LE_PHY_PARAM_2M BT_CONN_LE_PHY_PARAM(BT_GAP_LE_PHY_2M, \ BT_GAP_LE_PHY_2M) /** Only LE Coded PHY. */ #define BT_CONN_LE_PHY_PARAM_CODED BT_CONN_LE_PHY_PARAM(BT_GAP_LE_PHY_CODED, \ BT_GAP_LE_PHY_CODED) /** All LE PHYs. */ #define BT_CONN_LE_PHY_PARAM_ALL BT_CONN_LE_PHY_PARAM(BT_GAP_LE_PHY_1M | \ BT_GAP_LE_PHY_2M | \ BT_GAP_LE_PHY_CODED, \ BT_GAP_LE_PHY_1M | \ BT_GAP_LE_PHY_2M | \ BT_GAP_LE_PHY_CODED) /** Connection data length information for LE connections */ struct bt_conn_le_data_len_info { /** Maximum Link Layer transmission payload size in bytes. */ uint16_t tx_max_len; /** Maximum Link Layer transmission payload time in us. */ uint16_t tx_max_time; /** Maximum Link Layer reception payload size in bytes. */ uint16_t rx_max_len; /** Maximum Link Layer reception payload time in us. */ uint16_t rx_max_time; }; /** Connection data length parameters for LE connections */ struct bt_conn_le_data_len_param { /** Maximum Link Layer transmission payload size in bytes. */ uint16_t tx_max_len; /** Maximum Link Layer transmission payload time in us. */ uint16_t tx_max_time; }; /** Initialize transmit data length parameters * * @param _tx_max_len Maximum Link Layer transmission payload size in bytes. * @param _tx_max_time Maximum Link Layer transmission payload time in us. */ #define BT_CONN_LE_DATA_LEN_PARAM_INIT(_tx_max_len, _tx_max_time) \ { \ .tx_max_len = (_tx_max_len), \ .tx_max_time = (_tx_max_time), \ } /** Helper to declare transmit data length parameters inline * * @param _tx_max_len Maximum Link Layer transmission payload size in bytes. * @param _tx_max_time Maximum Link Layer transmission payload time in us. */ #define BT_CONN_LE_DATA_LEN_PARAM(_tx_max_len, _tx_max_time) \ ((struct bt_conn_le_data_len_param[]) { \ BT_CONN_LE_DATA_LEN_PARAM_INIT(_tx_max_len, _tx_max_time) \ }) /** Default LE data length parameters. */ #define BT_LE_DATA_LEN_PARAM_DEFAULT \ BT_CONN_LE_DATA_LEN_PARAM(BT_GAP_DATA_LEN_DEFAULT, \ BT_GAP_DATA_TIME_DEFAULT) /** Maximum LE data length parameters. */ #define BT_LE_DATA_LEN_PARAM_MAX \ BT_CONN_LE_DATA_LEN_PARAM(BT_GAP_DATA_LEN_MAX, \ BT_GAP_DATA_TIME_MAX) /** @brief Increment a connection's reference count. * * Increment the reference count of a connection object. * * @note Will return NULL if the reference count is zero. * * @param conn Connection object. * * @return Connection object with incremented reference count, or NULL if the * reference count is zero. */ struct bt_conn *bt_conn_ref(struct bt_conn *conn); /** @brief Decrement a connection's reference count. * * Decrement the reference count of a connection object. * * @param conn Connection object. */ void bt_conn_unref(struct bt_conn *conn); /** @brief Iterate through all existing connections. * * @param type Connection Type * @param func Function to call for each connection. * @param data Data to pass to the callback function. */ void bt_conn_foreach(int type, void (*func)(struct bt_conn *conn, void *data), void *data); /** @brief Look up an existing connection by address. * * Look up an existing connection based on the remote address. * * The caller gets a new reference to the connection object which must be * released with bt_conn_unref() once done using the object. * * @param id Local identity (in most cases BT_ID_DEFAULT). * @param peer Remote address. * * @return Connection object or NULL if not found. */ struct bt_conn *bt_conn_lookup_addr_le(uint8_t id, const bt_addr_le_t *peer); /** @brief Get destination (peer) address of a connection. * * @param conn Connection object. * * @return Destination address. */ const bt_addr_le_t *bt_conn_get_dst(const struct bt_conn *conn); /** @brief Get array index of a connection * * This function is used to map bt_conn to index of an array of * connections. The array has CONFIG_BT_MAX_CONN elements. * * @param conn Connection object. * * @return Index of the connection object. * The range of the returned value is 0..CONFIG_BT_MAX_CONN-1 */ uint8_t bt_conn_index(struct bt_conn *conn); /** Connection Type */ enum { /** LE Connection Type */ BT_CONN_TYPE_LE = BIT(0), /** BR/EDR Connection Type */ BT_CONN_TYPE_BR = BIT(1), /** SCO Connection Type */ BT_CONN_TYPE_SCO = BIT(2), /** ISO Connection Type */ BT_CONN_TYPE_ISO = BIT(3), /** All Connection Type */ BT_CONN_TYPE_ALL = BT_CONN_TYPE_LE | BT_CONN_TYPE_BR | BT_CONN_TYPE_SCO | BT_CONN_TYPE_ISO, }; /** LE Connection Info Structure */ struct bt_conn_le_info { /** Source (Local) Identity Address */ const bt_addr_le_t *src; /** Destination (Remote) Identity Address or remote Resolvable Private * Address (RPA) before identity has been resolved. */ const bt_addr_le_t *dst; /** Local device address used during connection setup. */ const bt_addr_le_t *local; /** Remote device address used during connection setup. */ const bt_addr_le_t *remote; uint16_t interval; /** Connection interval */ uint16_t latency; /** Connection peripheral latency */ uint16_t timeout; /** Connection supervision timeout */ #if defined(CONFIG_BT_USER_PHY_UPDATE) const struct bt_conn_le_phy_info *phy; #endif /* defined(CONFIG_BT_USER_PHY_UPDATE) */ #if defined(CONFIG_BT_USER_DATA_LEN_UPDATE) /* Connection maximum single fragment parameters */ const struct bt_conn_le_data_len_info *data_len; #endif /* defined(CONFIG_BT_USER_DATA_LEN_UPDATE) */ }; /** BR/EDR Connection Info Structure */ struct bt_conn_br_info { const bt_addr_t *dst; /** Destination (Remote) BR/EDR address */ }; enum { BT_CONN_ROLE_CENTRAL = 0, BT_CONN_ROLE_PERIPHERAL = 1, }; /** Connection role (central or peripheral) */ #define BT_CONN_ROLE_MASTER __DEPRECATED_MACRO BT_CONN_ROLE_CENTRAL #define BT_CONN_ROLE_SLAVE __DEPRECATED_MACRO BT_CONN_ROLE_PERIPHERAL /** Connection Info Structure */ struct bt_conn_info { /** Connection Type. */ uint8_t type; /** Connection Role. */ uint8_t role; /** Which local identity the connection was created with */ uint8_t id; /** Connection Type specific Info.*/ union { /** LE Connection specific Info. */ struct bt_conn_le_info le; /** BR/EDR Connection specific Info. */ struct bt_conn_br_info br; }; }; /** LE Connection Remote Info Structure */ struct bt_conn_le_remote_info { /** Remote LE feature set (bitmask). */ const uint8_t *features; }; /** BR/EDR Connection Remote Info structure */ struct bt_conn_br_remote_info { /** Remote feature set (pages of bitmasks). */ const uint8_t *features; /** Number of pages in the remote feature set. */ uint8_t num_pages; }; /** @brief Connection Remote Info Structure * * @note The version, manufacturer and subversion fields will only contain * valid data if @kconfig{CONFIG_BT_REMOTE_VERSION} is enabled. */ struct bt_conn_remote_info { /** Connection Type */ uint8_t type; /** Remote Link Layer version */ uint8_t version; /** Remote manufacturer identifier */ uint16_t manufacturer; /** Per-manufacturer unique revision */ uint16_t subversion; union { /** LE connection remote info */ struct bt_conn_le_remote_info le; /** BR/EDR connection remote info */ struct bt_conn_br_remote_info br; }; }; enum bt_conn_le_tx_power_phy { /** Convenience macro for when no PHY is set. */ BT_CONN_LE_TX_POWER_PHY_NONE, /** LE 1M PHY */ BT_CONN_LE_TX_POWER_PHY_1M, /** LE 2M PHY */ BT_CONN_LE_TX_POWER_PHY_2M, /** LE Coded PHY using S=8 coding. */ BT_CONN_LE_TX_POWER_PHY_CODED_S8, /** LE Coded PHY using S=2 coding. */ BT_CONN_LE_TX_POWER_PHY_CODED_S2, }; /** LE Transmit Power Level Structure */ struct bt_conn_le_tx_power { /** Input: 1M, 2M, Coded S2 or Coded S8 */ uint8_t phy; /** Output: current transmit power level */ int8_t current_level; /** Output: maximum transmit power level */ int8_t max_level; }; /** @brief Get connection info * * @param conn Connection object. * @param info Connection info object. * * @return Zero on success or (negative) error code on failure. */ int bt_conn_get_info(const struct bt_conn *conn, struct bt_conn_info *info); /** @brief Get connection info for the remote device. * * @param conn Connection object. * @param remote_info Connection remote info object. * * @note In order to retrieve the remote version (version, manufacturer * and subversion) @kconfig{CONFIG_BT_REMOTE_VERSION} must be enabled * * @note The remote information is exchanged directly after the connection has * been established. The application can be notified about when the remote * information is available through the remote_info_available callback. * * @return Zero on success or (negative) error code on failure. * @return -EBUSY The remote information is not yet available. */ int bt_conn_get_remote_info(struct bt_conn *conn, struct bt_conn_remote_info *remote_info); /** @brief Get connection transmit power level. * * @param conn Connection object. * @param tx_power_level Transmit power level descriptor. * * @return Zero on success or (negative) error code on failure. * @return -ENOBUFS HCI command buffer is not available. */ int bt_conn_le_get_tx_power_level(struct bt_conn *conn, struct bt_conn_le_tx_power *tx_power_level); /** @brief Update the connection parameters. * * If the local device is in the peripheral role then updating the connection * parameters will be delayed. This delay can be configured by through the * @kconfig{CONFIG_BT_CONN_PARAM_UPDATE_TIMEOUT} option. * * @param conn Connection object. * @param param Updated connection parameters. * * @return Zero on success or (negative) error code on failure. */ int bt_conn_le_param_update(struct bt_conn *conn, const struct bt_le_conn_param *param); /** @brief Update the connection transmit data length parameters. * * @param conn Connection object. * @param param Updated data length parameters. * * @return Zero on success or (negative) error code on failure. */ int bt_conn_le_data_len_update(struct bt_conn *conn, const struct bt_conn_le_data_len_param *param); /** @brief Update the connection PHY parameters. * * Update the preferred transmit and receive PHYs of the connection. * Use @ref BT_GAP_LE_PHY_NONE to indicate no preference. * * @param conn Connection object. * @param param Updated connection parameters. * * @return Zero on success or (negative) error code on failure. */ int bt_conn_le_phy_update(struct bt_conn *conn, const struct bt_conn_le_phy_param *param); /** @brief Disconnect from a remote device or cancel pending connection. * * Disconnect an active connection with the specified reason code or cancel * pending outgoing connection. * * The disconnect reason for a normal disconnect should be: * @ref BT_HCI_ERR_REMOTE_USER_TERM_CONN. * * The following disconnect reasons are accepted: * - @ref BT_HCI_ERR_AUTH_FAIL * - @ref BT_HCI_ERR_REMOTE_USER_TERM_CONN * - @ref BT_HCI_ERR_REMOTE_LOW_RESOURCES * - @ref BT_HCI_ERR_REMOTE_POWER_OFF * - @ref BT_HCI_ERR_UNSUPP_REMOTE_FEATURE * - @ref BT_HCI_ERR_PAIRING_NOT_SUPPORTED * - @ref BT_HCI_ERR_UNACCEPT_CONN_PARAM * * @param conn Connection to disconnect. * @param reason Reason code for the disconnection. * * @return Zero on success or (negative) error code on failure. */ int bt_conn_disconnect(struct bt_conn *conn, uint8_t reason); enum { /** Convenience value when no options are specified. */ BT_CONN_LE_OPT_NONE = 0, /** @brief Enable LE Coded PHY. * * Enable scanning on the LE Coded PHY. */ BT_CONN_LE_OPT_CODED = BIT(0), /** @brief Disable LE 1M PHY. * * Disable scanning on the LE 1M PHY. * * @note Requires @ref BT_CONN_LE_OPT_CODED. */ BT_CONN_LE_OPT_NO_1M = BIT(1), }; struct bt_conn_le_create_param { /** Bit-field of create connection options. */ uint32_t options; /** Scan interval (N * 0.625 ms) */ uint16_t interval; /** Scan window (N * 0.625 ms) */ uint16_t window; /** @brief Scan interval LE Coded PHY (N * 0.625 MS) * * Set zero to use same as LE 1M PHY scan interval */ uint16_t interval_coded; /** @brief Scan window LE Coded PHY (N * 0.625 MS) * * Set zero to use same as LE 1M PHY scan window. */ uint16_t window_coded; /** @brief Connection initiation timeout (N * 10 MS) * * Set zero to use the default @kconfig{CONFIG_BT_CREATE_CONN_TIMEOUT} * timeout. * * @note Unused in @ref bt_conn_le_create_auto */ uint16_t timeout; }; /** @brief Initialize create connection parameters * * @param _options Create connection options. * @param _interval Create connection scan interval (N * 0.625 ms). * @param _window Create connection scan window (N * 0.625 ms). */ #define BT_CONN_LE_CREATE_PARAM_INIT(_options, _interval, _window) \ { \ .options = (_options), \ .interval = (_interval), \ .window = (_window), \ .interval_coded = 0, \ .window_coded = 0, \ .timeout = 0, \ } /** Helper to declare create connection parameters inline * * @param _options Create connection options. * @param _interval Create connection scan interval (N * 0.625 ms). * @param _window Create connection scan window (N * 0.625 ms). */ #define BT_CONN_LE_CREATE_PARAM(_options, _interval, _window) \ ((struct bt_conn_le_create_param[]) { \ BT_CONN_LE_CREATE_PARAM_INIT(_options, _interval, _window) \ }) /** Default LE create connection parameters. * Scan continuously by setting scan interval equal to scan window. */ #define BT_CONN_LE_CREATE_CONN \ BT_CONN_LE_CREATE_PARAM(BT_CONN_LE_OPT_NONE, \ BT_GAP_SCAN_FAST_INTERVAL, \ BT_GAP_SCAN_FAST_INTERVAL) /** Default LE create connection using filter accept list parameters. * Scan window: 30 ms. * Scan interval: 60 ms. */ #define BT_CONN_LE_CREATE_CONN_AUTO \ BT_CONN_LE_CREATE_PARAM(BT_CONN_LE_OPT_NONE, \ BT_GAP_SCAN_FAST_INTERVAL, \ BT_GAP_SCAN_FAST_WINDOW) /** @brief Initiate an LE connection to a remote device. * * Allows initiate new LE link to remote peer using its address. * * The caller gets a new reference to the connection object which must be * released with bt_conn_unref() once done using the object. * * This uses the General Connection Establishment procedure. * * The application must disable explicit scanning before initiating * a new LE connection. * * @param[in] peer Remote address. * @param[in] create_param Create connection parameters. * @param[in] conn_param Initial connection parameters. * @param[out] conn Valid connection object on success. * * @return Zero on success or (negative) error code on failure. */ int bt_conn_le_create(const bt_addr_le_t *peer, const struct bt_conn_le_create_param *create_param, const struct bt_le_conn_param *conn_param, struct bt_conn **conn); /** @brief Automatically connect to remote devices in the filter accept list.. * * This uses the Auto Connection Establishment procedure. * The procedure will continue until a single connection is established or the * procedure is stopped through @ref bt_conn_create_auto_stop. * To establish connections to all devices in the the filter accept list the * procedure should be started again in the connected callback after a * new connection has been established. * * @param create_param Create connection parameters * @param conn_param Initial connection parameters. * * @return Zero on success or (negative) error code on failure. * @return -ENOMEM No free connection object available. */ int bt_conn_le_create_auto(const struct bt_conn_le_create_param *create_param, const struct bt_le_conn_param *conn_param); /** @brief Stop automatic connect creation. * * @return Zero on success or (negative) error code on failure. */ int bt_conn_create_auto_stop(void); /** @brief Automatically connect to remote device if it's in range. * * This function enables/disables automatic connection initiation. * Every time the device loses the connection with peer, this connection * will be re-established if connectable advertisement from peer is received. * * @note Auto connect is disabled during explicit scanning. * * @param addr Remote Bluetooth address. * @param param If non-NULL, auto connect is enabled with the given * parameters. If NULL, auto connect is disabled. * * @return Zero on success or error code otherwise. */ int bt_le_set_auto_conn(const bt_addr_le_t *addr, const struct bt_le_conn_param *param); /** Security level. */ typedef enum __packed { /** Level 0: Only for BR/EDR special cases, like SDP */ BT_SECURITY_L0, /** Level 1: No encryption and no authentication. */ BT_SECURITY_L1, /** Level 2: Encryption and no authentication (no MITM). */ BT_SECURITY_L2, /** Level 3: Encryption and authentication (MITM). */ BT_SECURITY_L3, /** Level 4: Authenticated Secure Connections and 128-bit key. */ BT_SECURITY_L4, /** Bit to force new pairing procedure, bit-wise OR with requested * security level. */ BT_SECURITY_FORCE_PAIR = BIT(7), } bt_security_t; /** @brief Set security level for a connection. * * This function enable security (encryption) for a connection. If the device * has bond information for the peer with sufficiently strong key encryption * will be enabled. If the connection is already encrypted with sufficiently * strong key this function does nothing. * * If the device has no bond information for the peer and is not already paired * then the pairing procedure will be initiated. If the device has bond * information or is already paired and the keys are too weak then the pairing * procedure will be initiated. * * This function may return error if required level of security is not possible * to achieve due to local or remote device limitation (e.g., input output * capabilities), or if the maximum number of paired devices has been reached. * * This function may return error if the pairing procedure has already been * initiated by the local device or the peer device. * * @note When @kconfig{CONFIG_BT_SMP_SC_ONLY} is enabled then the security * level will always be level 4. * * @note When @kconfig{CONFIG_BT_SMP_OOB_LEGACY_PAIR_ONLY} is enabled then the * security level will always be level 3. * * @param conn Connection object. * @param sec Requested security level. * * @return 0 on success or negative error */ int bt_conn_set_security(struct bt_conn *conn, bt_security_t sec); /** @brief Get security level for a connection. * * @return Connection security level */ bt_security_t bt_conn_get_security(struct bt_conn *conn); /** @brief Get encryption key size. * * This function gets encryption key size. * If there is no security (encryption) enabled 0 will be returned. * * @param conn Existing connection object. * * @return Encryption key size. */ uint8_t bt_conn_enc_key_size(struct bt_conn *conn); enum bt_security_err { /** Security procedure successful. */ BT_SECURITY_ERR_SUCCESS, /** Authentication failed. */ BT_SECURITY_ERR_AUTH_FAIL, /** PIN or encryption key is missing. */ BT_SECURITY_ERR_PIN_OR_KEY_MISSING, /** OOB data is not available. */ BT_SECURITY_ERR_OOB_NOT_AVAILABLE, /** The requested security level could not be reached. */ BT_SECURITY_ERR_AUTH_REQUIREMENT, /** Pairing is not supported */ BT_SECURITY_ERR_PAIR_NOT_SUPPORTED, /** Pairing is not allowed. */ BT_SECURITY_ERR_PAIR_NOT_ALLOWED, /** Invalid parameters. */ BT_SECURITY_ERR_INVALID_PARAM, /** Pairing failed but the exact reason could not be specified. */ BT_SECURITY_ERR_UNSPECIFIED, }; /** @brief Connection callback structure. * * This structure is used for tracking the state of a connection. * It is registered with the help of the bt_conn_cb_register() API. * It's permissible to register multiple instances of this @ref bt_conn_cb * type, in case different modules of an application are interested in * tracking the connection state. If a callback is not of interest for * an instance, it may be set to NULL and will as a consequence not be * used for that instance. */ struct bt_conn_cb { /** @brief A new connection has been established. * * This callback notifies the application of a new connection. * In case the err parameter is non-zero it means that the * connection establishment failed. * * @note If the connection was established from an advertising set then * the advertising set cannot be restarted directly from this * callback. Instead use the connected callback of the * advertising set. * * @param conn New connection object. * @param err HCI error. Zero for success, non-zero otherwise. * * @p err can mean either of the following: * - @ref BT_HCI_ERR_UNKNOWN_CONN_ID Creating the connection started by * @ref bt_conn_le_create was canceled either by the user through * @ref bt_conn_disconnect or by the timeout in the host through * @ref bt_conn_le_create_param timeout parameter, which defaults to * @kconfig{CONFIG_BT_CREATE_CONN_TIMEOUT} seconds. * - @p BT_HCI_ERR_ADV_TIMEOUT High duty cycle directed connectable * advertiser started by @ref bt_le_adv_start failed to be connected * within the timeout. */ void (*connected)(struct bt_conn *conn, uint8_t err); /** @brief A connection has been disconnected. * * This callback notifies the application that a connection * has been disconnected. * * When this callback is called the stack still has one reference to * the connection object. If the application in this callback tries to * start either a connectable advertiser or create a new connection * this might fail because there are no free connection objects * available. * To avoid this issue it is recommended to either start connectable * advertise or create a new connection using @ref k_work_submit or * increase @kconfig{CONFIG_BT_MAX_CONN}. * * @param conn Connection object. * @param reason HCI reason for the disconnection. */ void (*disconnected)(struct bt_conn *conn, uint8_t reason); /** @brief LE connection parameter update request. * * This callback notifies the application that a remote device * is requesting to update the connection parameters. The * application accepts the parameters by returning true, or * rejects them by returning false. Before accepting, the * application may also adjust the parameters to better suit * its needs. * * It is recommended for an application to have just one of these * callbacks for simplicity. However, if an application registers * multiple it needs to manage the potentially different * requirements for each callback. Each callback gets the * parameters as returned by previous callbacks, i.e. they are not * necessarily the same ones as the remote originally sent. * * If the application does not have this callback then the default * is to accept the parameters. * * @param conn Connection object. * @param param Proposed connection parameters. * * @return true to accept the parameters, or false to reject them. */ bool (*le_param_req)(struct bt_conn *conn, struct bt_le_conn_param *param); /** @brief The parameters for an LE connection have been updated. * * This callback notifies the application that the connection * parameters for an LE connection have been updated. * * @param conn Connection object. * @param interval Connection interval. * @param latency Connection latency. * @param timeout Connection supervision timeout. */ void (*le_param_updated)(struct bt_conn *conn, uint16_t interval, uint16_t latency, uint16_t timeout); #if defined(CONFIG_BT_SMP) /** @brief Remote Identity Address has been resolved. * * This callback notifies the application that a remote * Identity Address has been resolved * * @param conn Connection object. * @param rpa Resolvable Private Address. * @param identity Identity Address. */ void (*identity_resolved)(struct bt_conn *conn, const bt_addr_le_t *rpa, const bt_addr_le_t *identity); #endif /* CONFIG_BT_SMP */ #if defined(CONFIG_BT_SMP) || defined(CONFIG_BT_BREDR) /** @brief The security level of a connection has changed. * * This callback notifies the application that the security of a * connection has changed. * * The security level of the connection can either have been increased * or remain unchanged. An increased security level means that the * pairing procedure has been performed or the bond information from * a previous connection has been applied. If the security level * remains unchanged this means that the encryption key has been * refreshed for the connection. * * @param conn Connection object. * @param level New security level of the connection. * @param err Security error. Zero for success, non-zero otherwise. */ void (*security_changed)(struct bt_conn *conn, bt_security_t level, enum bt_security_err err); #endif /* defined(CONFIG_BT_SMP) || defined(CONFIG_BT_BREDR) */ #if defined(CONFIG_BT_REMOTE_INFO) /** @brief Remote information procedures has completed. * * This callback notifies the application that the remote information * has been retrieved from the remote peer. * * @param conn Connection object. * @param remote_info Connection information of remote device. */ void (*remote_info_available)(struct bt_conn *conn, struct bt_conn_remote_info *remote_info); #endif /* defined(CONFIG_BT_REMOTE_INFO) */ #if defined(CONFIG_BT_USER_PHY_UPDATE) /** @brief The PHY of the connection has changed. * * This callback notifies the application that the PHY of the * connection has changed. * * @param conn Connection object. * @param info Connection LE PHY information. */ void (*le_phy_updated)(struct bt_conn *conn, struct bt_conn_le_phy_info *param); #endif /* defined(CONFIG_BT_USER_PHY_UPDATE) */ #if defined(CONFIG_BT_USER_DATA_LEN_UPDATE) /** @brief The data length parameters of the connection has changed. * * This callback notifies the application that the maximum Link Layer * payload length or transmission time has changed. * * @param conn Connection object. * @param info Connection data length information. */ void (*le_data_len_updated)(struct bt_conn *conn, struct bt_conn_le_data_len_info *info); #endif /* defined(CONFIG_BT_USER_DATA_LEN_UPDATE) */ struct bt_conn_cb *_next; }; /** @brief Register connection callbacks. * * Register callbacks to monitor the state of connections. * * @param cb Callback struct. Must point to memory that remains valid. */ void bt_conn_cb_register(struct bt_conn_cb *cb); /** @def BT_CONN_CB_DEFINE * * @brief Register a callback structure for connection events. * * @param _name Name of callback structure. */ #define BT_CONN_CB_DEFINE(_name) \ static const STRUCT_SECTION_ITERABLE(bt_conn_cb, \ _CONCAT(bt_conn_cb_, \ _name)) /** @brief Enable/disable bonding. * * Set/clear the Bonding flag in the Authentication Requirements of * SMP Pairing Request/Response data. * The initial value of this flag depends on BT_BONDABLE Kconfig setting. * For the vast majority of applications calling this function shouldn't be * needed. * * @param enable Value allowing/disallowing to be bondable. */ void bt_set_bondable(bool enable); /** @brief Allow/disallow remote OOB data to be used for pairing. * * Set/clear the OOB data flag for SMP Pairing Request/Response data. * The initial value of this flag depends on BT_OOB_DATA_PRESENT Kconfig * setting. * * @param enable Value allowing/disallowing remote OOB data. */ void bt_set_oob_data_flag(bool enable); /** @brief Set OOB Temporary Key to be used for pairing * * This function allows to set OOB data for the LE legacy pairing procedure. * The function should only be called in response to the oob_data_request() * callback provided that the legacy method is user pairing. * * @param conn Connection object * @param tk Pointer to 16 byte long TK array * * @return Zero on success or -EINVAL if NULL */ int bt_le_oob_set_legacy_tk(struct bt_conn *conn, const uint8_t *tk); /** @brief Set OOB data during LE Secure Connections (SC) pairing procedure * * This function allows to set OOB data during the LE SC pairing procedure. * The function should only be called in response to the oob_data_request() * callback provided that LE SC method is used for pairing. * * The user should submit OOB data according to the information received in the * callback. This may yield three different configurations: with only local OOB * data present, with only remote OOB data present or with both local and * remote OOB data present. * * @param conn Connection object * @param oobd_local Local OOB data or NULL if not present * @param oobd_remote Remote OOB data or NULL if not present * * @return Zero on success or error code otherwise, positive in case of * protocol error or negative (POSIX) in case of stack internal error. */ int bt_le_oob_set_sc_data(struct bt_conn *conn, const struct bt_le_oob_sc_data *oobd_local, const struct bt_le_oob_sc_data *oobd_remote); /** @brief Get OOB data used for LE Secure Connections (SC) pairing procedure * * This function allows to get OOB data during the LE SC pairing procedure that * were set by the bt_le_oob_set_sc_data() API. * * @note The OOB data will only be available as long as the connection object * associated with it is valid. * * @param conn Connection object * @param oobd_local Local OOB data or NULL if not set * @param oobd_remote Remote OOB data or NULL if not set * * @return Zero on success or error code otherwise, positive in case of * protocol error or negative (POSIX) in case of stack internal error. */ int bt_le_oob_get_sc_data(struct bt_conn *conn, const struct bt_le_oob_sc_data **oobd_local, const struct bt_le_oob_sc_data **oobd_remote); /** @def BT_PASSKEY_INVALID * * Special passkey value that can be used to disable a previously * set fixed passkey. */ #define BT_PASSKEY_INVALID 0xffffffff /** @brief Set a fixed passkey to be used for pairing. * * This API is only available when the CONFIG_BT_FIXED_PASSKEY * configuration option has been enabled. * * Sets a fixed passkey to be used for pairing. If set, the * pairing_confim() callback will be called for all incoming pairings. * * @param passkey A valid passkey (0 - 999999) or BT_PASSKEY_INVALID * to disable a previously set fixed passkey. * * @return 0 on success or a negative error code on failure. */ int bt_passkey_set(unsigned int passkey); /** Info Structure for OOB pairing */ struct bt_conn_oob_info { /** Type of OOB pairing method */ enum { /** LE legacy pairing */ BT_CONN_OOB_LE_LEGACY, /** LE SC pairing */ BT_CONN_OOB_LE_SC, } type; union { /** LE Secure Connections OOB pairing parameters */ struct { /** OOB data configuration */ enum { /** Local OOB data requested */ BT_CONN_OOB_LOCAL_ONLY, /** Remote OOB data requested */ BT_CONN_OOB_REMOTE_ONLY, /** Both local and remote OOB data requested */ BT_CONN_OOB_BOTH_PEERS, /** No OOB data requested */ BT_CONN_OOB_NO_DATA, } oob_config; } lesc; }; }; #if defined(CONFIG_BT_SMP_APP_PAIRING_ACCEPT) /** @brief Pairing request and pairing response info structure. * * This structure is the same for both smp_pairing_req and smp_pairing_rsp * and a subset of the packet data, except for the initial Code octet. * It is documented in Core Spec. Vol. 3, Part H, 3.5.1 and 3.5.2. */ struct bt_conn_pairing_feat { /** IO Capability, Core Spec. Vol 3, Part H, 3.5.1, Table 3.4 */ uint8_t io_capability; /** OOB data flag, Core Spec. Vol 3, Part H, 3.5.1, Table 3.5 */ uint8_t oob_data_flag; /** AuthReq, Core Spec. Vol 3, Part H, 3.5.1, Fig. 3.3 */ uint8_t auth_req; /** Maximum Encryption Key Size, Core Spec. Vol 3, Part H, 3.5.1 */ uint8_t max_enc_key_size; /** Initiator Key Distribution/Generation, Core Spec. Vol 3, Part H, * 3.6.1, Fig. 3.11 */ uint8_t init_key_dist; /** Responder Key Distribution/Generation, Core Spec. Vol 3, Part H * 3.6.1, Fig. 3.11 */ uint8_t resp_key_dist; }; #endif /* CONFIG_BT_SMP_APP_PAIRING_ACCEPT */ /** Authenticated pairing callback structure */ struct bt_conn_auth_cb { #if defined(CONFIG_BT_SMP_APP_PAIRING_ACCEPT) /** @brief Query to proceed incoming pairing or not. * * On any incoming pairing req/rsp this callback will be called for * the application to decide whether to allow for the pairing to * continue. * * The pairing info received from the peer is passed to assist * making the decision. * * As this callback is synchronous the application should return * a response value immediately. Otherwise it may affect the * timing during pairing. Hence, this information should not be * conveyed to the user to take action. * * The remaining callbacks are not affected by this, but do notice * that other callbacks can be called during the pairing. Eg. if * pairing_confirm is registered both will be called for Just-Works * pairings. * * This callback may be unregistered in which case pairing continues * as if the Kconfig flag was not set. * * This callback is not called for BR/EDR Secure Simple Pairing (SSP). * * @param conn Connection where pairing is initiated. * @param feat Pairing req/resp info. */ enum bt_security_err (*pairing_accept)(struct bt_conn *conn, const struct bt_conn_pairing_feat *const feat); #endif /* CONFIG_BT_SMP_APP_PAIRING_ACCEPT */ /** @brief Display a passkey to the user. * * When called the application is expected to display the given * passkey to the user, with the expectation that the passkey will * then be entered on the peer device. The passkey will be in the * range of 0 - 999999, and is expected to be padded with zeroes so * that six digits are always shown. E.g. the value 37 should be * shown as 000037. * * This callback may be set to NULL, which means that the local * device lacks the ability do display a passkey. If set * to non-NULL the cancel callback must also be provided, since * this is the only way the application can find out that it should * stop displaying the passkey. * * @param conn Connection where pairing is currently active. * @param passkey Passkey to show to the user. */ void (*passkey_display)(struct bt_conn *conn, unsigned int passkey); /** @brief Request the user to enter a passkey. * * When called the user is expected to enter a passkey. The passkey * must be in the range of 0 - 999999, and should be expected to * be zero-padded, as that's how the peer device will typically be * showing it (e.g. 37 would be shown as 000037). * * Once the user has entered the passkey its value should be given * to the stack using the bt_conn_auth_passkey_entry() API. * * This callback may be set to NULL, which means that the local * device lacks the ability to enter a passkey. If set to non-NULL * the cancel callback must also be provided, since this is the * only way the application can find out that it should stop * requesting the user to enter a passkey. * * @param conn Connection where pairing is currently active. */ void (*passkey_entry)(struct bt_conn *conn); /** @brief Request the user to confirm a passkey. * * When called the user is expected to confirm that the given * passkey is also shown on the peer device.. The passkey will * be in the range of 0 - 999999, and should be zero-padded to * always be six digits (e.g. 37 would be shown as 000037). * * Once the user has confirmed the passkey to match, the * bt_conn_auth_passkey_confirm() API should be called. If the * user concluded that the passkey doesn't match the * bt_conn_auth_cancel() API should be called. * * This callback may be set to NULL, which means that the local * device lacks the ability to confirm a passkey. If set to non-NULL * the cancel callback must also be provided, since this is the * only way the application can find out that it should stop * requesting the user to confirm a passkey. * * @param conn Connection where pairing is currently active. * @param passkey Passkey to be confirmed. */ void (*passkey_confirm)(struct bt_conn *conn, unsigned int passkey); /** @brief Request the user to provide Out of Band (OOB) data. * * When called the user is expected to provide OOB data. The required * data are indicated by the information structure. * * For LE Secure Connections OOB pairing, the user should provide * local OOB data, remote OOB data or both depending on their * availability. Their value should be given to the stack using the * bt_le_oob_set_sc_data() API. * * This callback must be set to non-NULL in order to support OOB * pairing. * * @param conn Connection where pairing is currently active. * @param info OOB pairing information. */ void (*oob_data_request)(struct bt_conn *conn, struct bt_conn_oob_info *info); /** @brief Cancel the ongoing user request. * * This callback will be called to notify the application that it * should cancel any previous user request (passkey display, entry * or confirmation). * * This may be set to NULL, but must always be provided whenever the * passkey_display, passkey_entry passkey_confirm or pairing_confirm * callback has been provided. * * @param conn Connection where pairing is currently active. */ void (*cancel)(struct bt_conn *conn); /** @brief Request confirmation for an incoming pairing. * * This callback will be called to confirm an incoming pairing * request where none of the other user callbacks is applicable. * * If the user decides to accept the pairing the * bt_conn_auth_pairing_confirm() API should be called. If the * user decides to reject the pairing the bt_conn_auth_cancel() API * should be called. * * This callback may be set to NULL, which means that the local * device lacks the ability to confirm a pairing request. If set * to non-NULL the cancel callback must also be provided, since * this is the only way the application can find out that it should * stop requesting the user to confirm a pairing request. * * @param conn Connection where pairing is currently active. */ void (*pairing_confirm)(struct bt_conn *conn); #if defined(CONFIG_BT_BREDR) /** @brief Request the user to enter a passkey. * * This callback will be called for a BR/EDR (Bluetooth Classic) * connection where pairing is being performed. Once called the * user is expected to enter a PIN code with a length between * 1 and 16 digits. If the @a highsec parameter is set to true * the PIN code must be 16 digits long. * * Once entered, the PIN code should be given to the stack using * the bt_conn_auth_pincode_entry() API. * * This callback may be set to NULL, however in that case pairing * over BR/EDR will not be possible. If provided, the cancel * callback must be provided as well. * * @param conn Connection where pairing is currently active. * @param highsec true if 16 digit PIN is required. */ void (*pincode_entry)(struct bt_conn *conn, bool highsec); #endif /** @brief notify that pairing procedure was complete. * * This callback notifies the application that the pairing procedure * has been completed. * * @param conn Connection object. * @param bonded Bond information has been distributed during the * pairing procedure. */ void (*pairing_complete)(struct bt_conn *conn, bool bonded); /** @brief notify that pairing process has failed. * * @param conn Connection object. * @param reason Pairing failed reason */ void (*pairing_failed)(struct bt_conn *conn, enum bt_security_err reason); /** @brief Notify that bond has been deleted. * * This callback notifies the application that the bond information * for the remote peer has been deleted * * @param id Which local identity had the bond. * @param peer Remote address. */ void (*bond_deleted)(uint8_t id, const bt_addr_le_t *peer); }; /** @brief Register authentication callbacks. * * Register callbacks to handle authenticated pairing. Passing NULL * unregisters a previous callbacks structure. * * @param cb Callback struct. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_cb_register(const struct bt_conn_auth_cb *cb); /** @brief Reply with entered passkey. * * This function should be called only after passkey_entry callback from * bt_conn_auth_cb structure was called. * * @param conn Connection object. * @param passkey Entered passkey. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_passkey_entry(struct bt_conn *conn, unsigned int passkey); /** @brief Cancel ongoing authenticated pairing. * * This function allows to cancel ongoing authenticated pairing. * * @param conn Connection object. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_cancel(struct bt_conn *conn); /** @brief Reply if passkey was confirmed to match by user. * * This function should be called only after passkey_confirm callback from * bt_conn_auth_cb structure was called. * * @param conn Connection object. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_passkey_confirm(struct bt_conn *conn); /** @brief Reply if incoming pairing was confirmed by user. * * This function should be called only after pairing_confirm callback from * bt_conn_auth_cb structure was called if user confirmed incoming pairing. * * @param conn Connection object. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_pairing_confirm(struct bt_conn *conn); /** @brief Reply with entered PIN code. * * This function should be called only after PIN code callback from * bt_conn_auth_cb structure was called. It's for legacy 2.0 devices. * * @param conn Connection object. * @param pin Entered PIN code. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_pincode_entry(struct bt_conn *conn, const char *pin); /** Connection parameters for BR/EDR connections */ struct bt_br_conn_param { bool allow_role_switch; }; /** @brief Initialize BR/EDR connection parameters * * @param role_switch True if role switch is allowed */ #define BT_BR_CONN_PARAM_INIT(role_switch) \ { \ .allow_role_switch = (role_switch), \ } /** Helper to declare BR/EDR connection parameters inline * * @param role_switch True if role switch is allowed */ #define BT_BR_CONN_PARAM(role_switch) \ ((struct bt_br_conn_param[]) { \ BT_BR_CONN_PARAM_INIT(role_switch) \ }) /** Default BR/EDR connection parameters: * Role switch allowed */ #define BT_BR_CONN_PARAM_DEFAULT BT_BR_CONN_PARAM(true) /** @brief Initiate an BR/EDR connection to a remote device. * * Allows initiate new BR/EDR link to remote peer using its address. * * The caller gets a new reference to the connection object which must be * released with bt_conn_unref() once done using the object. * * @param peer Remote address. * @param param Initial connection parameters. * * @return Valid connection object on success or NULL otherwise. */ struct bt_conn *bt_conn_create_br(const bt_addr_t *peer, const struct bt_br_conn_param *param); /** @brief Initiate an SCO connection to a remote device. * * Allows initiate new SCO link to remote peer using its address. * * The caller gets a new reference to the connection object which must be * released with bt_conn_unref() once done using the object. * * @param peer Remote address. * * @return Valid connection object on success or NULL otherwise. */ struct bt_conn *bt_conn_create_sco(const bt_addr_t *peer); #ifdef __cplusplus } #endif /** * @} */ #endif /* ZEPHYR_INCLUDE_BLUETOOTH_CONN_H_ */