# Bluetooth ATT/GATT configuration options # Copyright (c) 2019 Intel Corporation # SPDX-License-Identifier: Apache-2.0 menu "ATT and GATT Options" config BT_ATT_ERR_TO_STR bool "Print ATT error codes as strings [EXPERIMENTAL]" select EXPERIMENTAL help This configuration enables printing of ATT error codes represented as strings. See bt_att_err_to_str() for more details. config BT_ATT_TX_COUNT int "Number of ATT buffers" default BT_BUF_ACL_TX_COUNT default 3 range 1 $(UINT8_MAX) help These buffers are only used for sending anything over ATT. Requests, responses, indications, confirmations, notifications. config BT_ATT_PREPARE_COUNT int "Number of ATT prepare write buffers" default 0 range 0 64 help Number of buffers available for ATT prepare write, setting this to 0 disables GATT long/reliable writes. config BT_ATT_RETRY_ON_SEC_ERR bool "Automatic security elevation and retry on security errors" default y depends on BT_SMP help If an ATT request fails due to insufficient security, the host will try to elevate the security level and retry the ATT request. config BT_EATT bool "Enhanced ATT Bearers support [EXPERIMENTAL]" depends on BT_L2CAP_ECRED select EXPERIMENTAL select BT_GATT_READ_MULT_VAR_LEN help This option enables support for Enhanced ATT bearers support. When enabled additional L2CAP channels can be connected as bearers enabling multiple outstanding request. if BT_EATT config BT_EATT_MAX int "Maximum number of Enhanced ATT bearers" default 3 range 1 16 help Number of Enhanced ATT bearers available. config BT_EATT_AUTO_CONNECT bool "Automatically connect EATT bearers when a link is established" default y help The device will try to connect BT_EATT_MAX enhanced ATT bearers when a connection to a peer is established. endif # BT_EATT config BT_GATT_AUTO_RESUBSCRIBE bool "Automatic re-subscription to characteristics" default y imply BT_GATT_AUTO_SEC_REQ depends on BT_GATT_CLIENT help Quirk: upon re-establishing a bonded connection, assumes the remote forgot the CCC values and sets them again. If this behavior is not desired for a particular subscription, set the `BT_GATT_SUBSCRIBE_FLAG_NO_RESUB` flag. This also means that upon a reconnection, the application will get an unprompted call to its `subscribe` callback. config BT_GATT_AUTO_SEC_REQ bool "Automatic security re-establishment request as a peripheral" default y depends on BT_SMP help This option requests security re-establishment automatically whenever a reconnection to a GATT client is established and there are notifiable or indicatable characteristics for which security is required. This configuration option only applies to the peripheral role, which sends a Security Request for this purpose. When disabled, it is the application's responsibility to call bt_conn_set_security() to re-establish security prior to sending any notifications or indications on the characteristics that require security (unless the central does that first). This option has been introduced to avoid interoperability issues with commercially available central devices that react negatively to receiving a Security Request immediately after reconnection. config BT_GATT_SERVICE_CHANGED bool "GATT Service Changed support" default y help This option enables support for the service changed characteristic. config BT_GATT_DYNAMIC_DB bool "GATT dynamic database support" depends on BT_GATT_SERVICE_CHANGED help This option enables registering/unregistering services at runtime. config BT_GATT_CACHING bool "GATT Caching support" default y depends on BT_GATT_SERVICE_CHANGED depends on PSA_CRYPTO_CLIENT select PSA_WANT_KEY_TYPE_AES select PSA_WANT_ALG_CMAC select MBEDTLS_AES_ROM_TABLES if MBEDTLS_PSA_CRYPTO_C help This option enables support for GATT Caching. When enabled the stack will register Client Supported Features and Database Hash characteristics which can be used by clients to detect if anything has changed on the GATT database. if BT_GATT_CACHING config BT_GATT_NOTIFY_MULTIPLE bool "GATT Notify Multiple Characteristic Values support" depends on BT_GATT_CACHING help This option enables support for the GATT Notify Multiple Characteristic Values procedure. if BT_GATT_NOTIFY_MULTIPLE config BT_GATT_NOTIFY_MULTIPLE_FLUSH_MS int "Delay for batching multiple notifications in a single PDU." default 1 range 0 4000 help Sets the time (in milliseconds) during which consecutive GATT notifications will be tentatively appended to form a single ATT_MULTIPLE_HANDLE_VALUE_NTF PDU. If set to 0, batching is disabled. Then, the only way to send ATT_MULTIPLE_HANDLE_VALUE_NTF PDUs is to use bt_gatt_notify_multiple. See the documentation of bt_gatt_notify() for more details. endif # BT_GATT_NOTIFY_MULTIPLE config BT_GATT_ENFORCE_CHANGE_UNAWARE bool "GATT Enforce change-unaware state" depends on BT_GATT_CACHING help When enable this option blocks notification and indications to client to conform to the following statement from the Bluetooth 5.1 specification: '...the server shall not send notifications and indications to such a client until it becomes change-aware." In case the service cannot deal with sudden errors (-EAGAIN) then it shall not use this option. endif # BT_GATT_CACHING config BT_GATT_ENFORCE_SUBSCRIPTION bool "GATT Enforce characteristic subscription" default y help When enabled, this option will make the server block sending notifications and indications to a device which has not subscribed to the supplied characteristic. config BT_GATT_CLIENT bool "GATT client support" help This option enables support for the GATT Client role. config BT_GATT_READ_MULTIPLE bool "GATT Read Multiple Characteristic Values support" default y help This option enables support for the GATT Read Multiple Characteristic Values procedure. config BT_GATT_READ_MULT_VAR_LEN bool "GATT Read Multiple Variable Length Characteristic Values support" default y help This option enables support for the GATT Read Multiple Variable Length Characteristic Values procedure. Mandatory if EATT is enabled, optional otherwise (Core spec v5.3, Vol 3, Part G, Section 4.2, Table 4.1). config BT_GATT_AUTO_DISCOVER_CCC bool "Support to automatic discover the CCC handles of characteristics" depends on BT_GATT_CLIENT help This option enables support for GATT to initiate discovery for CCC handles if the CCC handle is unknown by the application. config BT_GATT_AUTO_UPDATE_MTU bool "Automatically send ATT MTU exchange request on connect" depends on BT_GATT_CLIENT help This option if enabled allows automatically sending request for ATT MTU exchange. config BT_GAP_AUTO_UPDATE_CONN_PARAMS bool "Automatic Update of Connection Parameters" default y depends on BT_PERIPHERAL help This option if enabled allows automatically sending request for connection parameters update after GAP recommended 5 seconds of connection as peripheral. config BT_GAP_PERIPHERAL_PREF_PARAMS bool "Configure peripheral preferred connection parameters" default y depends on BT_PERIPHERAL help This allows to configure peripheral preferred connection parameters. Enabling this option results in adding PPCP characteristic in GAP. If disabled it is up to application to set expected connection parameters. if BT_GAP_PERIPHERAL_PREF_PARAMS config BT_PERIPHERAL_PREF_MIN_INT int "Peripheral preferred minimum connection interval in 1.25ms units" default 24 range 6 $(UINT16_MAX) if !BT_CONN_PARAM_ANY help Range 3200 to 65534 is invalid. 65535 represents no specific value. config BT_PERIPHERAL_PREF_MAX_INT int "Peripheral preferred maximum connection interval in 1.25ms units" default 40 range 6 $(UINT16_MAX) if !BT_CONN_PARAM_ANY help Range 3200 to 65534 is invalid. 65535 represents no specific value. config BT_PERIPHERAL_PREF_LATENCY int "Peripheral preferred peripheral latency in Connection Intervals" default 0 range 0 499 if !BT_CONN_PARAM_ANY config BT_PERIPHERAL_PREF_TIMEOUT int "Peripheral preferred supervision timeout in 10ms units" default 42 range 10 $(UINT16_MAX) if !BT_CONN_PARAM_ANY help It is up to user to provide valid timeout which pass required minimum value: in milliseconds it shall be larger than "(1+ Conn_Latency) * Conn_Interval_Max * 2" where Conn_Interval_Max is given in milliseconds. Range 3200 to 65534 is invalid. 65535 represents no specific value. endif # BT_GAP_PERIPHERAL_PREF_PARAMS config BT_DEVICE_NAME_GATT_WRITABLE bool "Allow to write device name by remote GATT clients" depends on BT_DEVICE_NAME_DYNAMIC default y help Enabling this option allows remote GATT clients to write to device name GAP characteristic. if BT_DEVICE_NAME_GATT_WRITABLE choice BT_DEVICE_NAME_GATT_WRITABLE_SECURITY prompt "Security requirements" default DEVICE_NAME_GATT_WRITABLE_ENCRYPT help Select security requirementsf for writing device name by remote GATT clients. config DEVICE_NAME_GATT_WRITABLE_NONE bool "No requirements" config DEVICE_NAME_GATT_WRITABLE_ENCRYPT bool "Encryption required" config DEVICE_NAME_GATT_WRITABLE_AUTHEN bool "Encryption and authentication required" endchoice #BT_DEVICE_NAME_GATT_WRITABLE_SECURITY endif #BT_DEVICE_NAME_GATT_WRITABLE config BT_DEVICE_APPEARANCE_GATT_WRITABLE bool "Allow to write GAP Appearance by remote GATT clients" depends on BT_DEVICE_APPEARANCE_DYNAMIC default y help Enabling this option allows remote GATT clients to write to device appearance GAP characteristic. if BT_DEVICE_APPEARANCE_GATT_WRITABLE choice BT_DEVICE_APPEARANCE_GATT_WRITABLE prompt "Security requirements" default DEVICE_APPEARANCE_GATT_WRITABLE_AUTHEN help Select security requirementsf for writing device name by remote GATT clients. config BT_DEVICE_APPEARANCE_GATT_WRITABLE_NONE bool "No requirements" config BT_DEVICE_APPEARANCE_GATT_WRITABLE_ENCRYPT bool "Encryption required" config DEVICE_APPEARANCE_GATT_WRITABLE_AUTHEN bool "Encryption and authentication required" endchoice #BT_DEVICE_APPEARANCE_GATT_WRITABLE endif #BT_DEVICE_APPEARANCE_GATT_WRITABLE config BT_GATT_AUTHORIZATION_CUSTOM bool "Custom authorization of GATT operations" help This option allows the user to define application-specific authorization logic for GATT operations that can be registered with the bt_gatt_authorization_cb_register API. See the API documentation for more details. endmenu