1# Change Log 2All notable changes to this project will be documented in this file. 3 4The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) 5and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html). 6 7--- 8 9## Unreleased 10 11### Added 12- HCI: ENABLE_HCI_SERIALIZED_CONTROLLER_OPERATIONS serializes Inquiry, Remote Name Request and Create Connection operations 13- GAP: support extended advertising with ENABLE_LE_EXTENDED_ADVERTISING 14- GAP: gap_enable_link_watchdog() uses automatic flush timeout to disconnect if data cannot be sent 15- GAP: gap_secure_connections_active() to query if BR/EDR Secure Connecions are possible 16- ATT DB: provide gatt_server_get_handle_range_for_service_with_uuid16 to find included service within handle range 17- GATT Service: Audio Input Control Service Server (AICS 1.0) 18- GATT Service: Volume Control Service Server (VCS 1.0) 19 20### Fixed 21- POSIX: fix RTS/CTS configuration by keeping local termios copy in btstack_uart_posix 22- HCI: fix handling of HCI Connection Complete with error (regression introduced in v1.5.1) 23- GAP: disable scanning, advertising, connection before updating random address 24- GAP: fix LE Scan with whitelist 25- HFP_AG: fix tracking for call dropped during outgoing ringing 26- HFP: Free HFP Connection object on SDP error / Service not found 27 28### Changed 29- Chipset: use da145xx in folder/file/function names for these SoCs 30- ATT Server: use uint8_t for status returns 31- AVDTP: use BLUETOOTH_SERVICE_CLASS_AUDIO_SINK / SOURCE instead of BLUETOOTH_PROTOCOL_AVDTP in SDP queries 32 33## Release v1.5.1 34 35### Added 36- GOEP Client: add goep_client_version_20_or_higher 37- ESP32: implement audio source 38 39### Fixed 40- PBAP Client: support disconnect while operation is ongoing 41- PBAP Client: use SRM only if GOEP v2.0 or higher connection 42- PBAP Client: emit vCard entry data as PBAP_DATA_PACKET 43- L2CAP: limit remote MTU by local tx configuration in ERTM 44 45### Changed 46- Example: init SM if LE supported to avoid issue with Android Cross-Transport Key-Derivation 47- ESP32: update sdkconfig for esp-idf v4.3, disable Bluedroid host stack 48- ESP32: use I2S configuration from ESP32 LyraT V4.3 49 50 51## Release v1.5.0 52 53### Added 54- HCI Dump: Support BTSnoop format in hci_dump_posix_fs.c for format = HCI_DUMP_BTSNOOP 55- HCI Dump RTT STDOUT: drop messages if RTT buffer is full and RTT is configured for non-blocking 56- HCI: hci_remove_event_handler to remove packet handler 57- hci_cmd: support variable length fields and arrayed parameters 58- GAP: ENABLE_EXPLICIT_LINK_KEY_REPLY allows for asynchronous link key lookup by application 59- GAP: gap_set_page_timeout to set Page Timeout 60- GAP: gap_inquiry_set_scan_activity to set Inquiry Scan Activity 61- L2CAP: emit L2CAP_EVENT_INFORMATION_RESPONSE event with extended features and fixed channels supported 62- L2CAP: support Enhanced Credit-based Flow-Control Mode for connection-oriented channels over BR/EDR/LE 63- A2DP: allow to register media codec validator for sink and source with: 64 - `a2dp_sink_register_media_config_validator` 65 - `a2dp_source_register_media_config_validator` 66- A2DP Sink: allow accept or reject of stream start on A2DP_SUBEVENT_START_STREAM_REQUESTED when ENABLE_AVDTP_ACCEPTOR_EXPLICIT_START_STREAM_CONFIRMATION is defined 67- OBEX: new obex_parser for chunked OBEX data 68- SM: Support Cross-Transport Key-Derivation (CTKD) of LE LTK from BR/EDR SC Link Key in Responder role 69- SM: sm_remove_event_handler to remove packet handler 70- GATT Service: Bond Management Service (BMS 1.0) Server 71- GATT Service: Microphone Control Service (MICS 1.0) Server 72- GATT Service: TX Power Service (TPS 1.0) Server 73- POSIX: btstack_signal allows to register for callback on signal, e.g. ctrl-c 74- Windows: btstack_stdin_window_register_ctrl_c_callback allows to register for ctrl-c 75 76### Fixed 77- A2DP Source: fix reconfigure 78- AVRCP Controller: prevent registering of notifications for unsupported events 79- RFCOMM: fixed handling of remote port configuration command 80- HFP AG: fix accept incoming connection while audio connection is established 81- PBAP Client: handle chunked vCard Listing 82- PBAP Client: use new streaming obex_parser to handle chunked OBEX data 83- SM: Work around for unexpected Windows 10 disconnect for BR Secure Connections (SMP over BR timeout) 84- SM: support storing bonding information for devices with identical IRK but different public addresses 85- GAP: restart advertising when private address changes 86- le_device_db_tlv: keep number of devices reported by le_device_db_count if old entry is replaced 87 88### Changed 89- Drop iOS support 90- HCI: provide status instead of undocumented int error code and bool for API functions 91- HCI: use 1000 ms watchdog to force power off for hci_power_control(HCI_POWER_OFF) 92- GAP: local name, EIR data, class of device and default link policy can be updated at any time 93- L2CAP: provide status instead of undocumented int error code and bool for API functions 94- L2CAP: remote features not required for SDP connections 95- L2CAP: replaced l2cap_register_packet_handler with l2cap_add_event_handler to register multiple handlers 96- L2CAP: drop reason parameter in l2cap_disconnect 97- L2CAP: use official terminology for L2CAP channel modes - ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE replaces ENABLE_LE_DATA_CHANNELS 98- L2CAP: unify API for can send now, request to send, and send packet and disconnect channel 99- L2CAP: unify events for can send now, packet sent, channel closed (CbM/ECBM using existing events) 100- RFCOMM: `RFCOMM_EVENT_PORT_CONFIGURATION` contains rfcomm_cid and remote flag, emitted for query config 101- RFCOMM: provide status instead of undocumented int error code and bool for API functions 102- RFCOMM: remote port configuration, line status, and modem status are sent by channel state machine 103- HSP: add ACL Connection to all events and BD ADDR to HSP_SUBEVENT_RFCOMM_CONNECTION_COMPLETE 104- HFP: API functions return status code if appropriate 105- HFP: removed one parameter from hfp_ag/hf_activate_voice_recognition function, introduce hfp_ag/hf_deactivate_voice_recognition instead 106- HFP: merged legacy and enhanced Voice Recognition Activation (VRA) API. If available enhanced mode will be preferred. 107- HFP: separate events for activation (HFP_SUBEVENT_VOICE_RECOGNITION_ACTIVATED) and deactivation (HFP_SUBEVENT_VOICE_RECOGNITION_DEACTIVATED) instead of combined HFP_SUBEVENT_VOICE_RECOGNITION_STATUS with status field. HFP_SUBEVENT_VOICE_RECOGNITION_ACTIVATED contains field "enhanced" to indicate if enhanced mode is used. 108- HFP: enhanced VRA: HFP_SUBEVENT_VOICE_RECOGNITION_ACTIVATED is emitted after VRA is ready and the the audio connection is established. This simplifies HFP HF client logic, i.e. client can call `hfp_hf_enhanced_voice_recognition_report_ready_for_audio directly` upon reception of HFP_SUBEVENT_VOICE_RECOGNITION_ACTIVATED event. 109- AVDTP: media config validator is called with preview of media codec configuration event and configured separately for sink/source 110- AVRCP: use PANEL as default unit + subunit info 111- AVRCP Controller: automatically query supported events when registering for notifications 112- AVRCP Target: cache companies and events in library and remove need to answer query in application callback. Use Bluetooth SIG as default company. 113- Run Loop: new functionality for HCI transport drivers and inter-process communication: 114 - *btstack_run_loop_poll_data_sources_from_irq*: used to transfer control from IRQ handler to main thread/run loop 115 - *btstack_run_loop_execute_on_main_thread*: schedule code execution on main thread from other thread 116 - *btstack_run_loop_trigger_exit*: trigger run loop exit 117- POSIX / Windows / Raspi / Qt: use updated ctrl-c handling 118- POSIX TLV: use max value size of 2048, assert in store function if value size is larger 119 120 121## Release v1.4.1 122 123### Added 124- GAP: emit GAP_EVENT_PAIRING_STARTED and GAP_EVENT_PAIRING_COMPLETE 125 126### Fixed 127- GAP: store link key in hci connection struct to allow authenticate after pairing without bonding 128- GAP: avoid requesting authentication twice 129- GAP: cache own address on start advertising and connecting, provide getters 130- GAP: stop LE connecting if create connection fails (e.g. connectable adv active and multiple roles not supported) 131- SM: fix race condition between local address changes and pairing procedure 132- ATT DB: fix spelling `gatt_server_get_handle_range_for_service_with_uuid128`, `gatt_server_get_handle_range_for_service_with_uuid16` 133 134### Changed 135- HCI: update advertising data without stopping advertising first 136- GAP: Drop local bonding flag in IO Capability Reply if remote does not indicate bonding 137- GAP: return status for `gap_set_security_mode` 138- GAP: abort legacy pairing if Level 4 is required 139- GAP: abort SSP on IO Capabilities Request event if Level 4 is required but SC not supported by remote 140- GAP: abort SSP on User Confirmation Request event if Level 3 is required but MITM protection not possible 141- GAP: validate minimal service security level can be reached during pairing in responder role 142- L2CAP: don't trigger hci disconnect if l2cap security requirements are insufficient 143- CVE-2020-26555: reject connections to and from devices with same BD ADDR 144- CVE-2020-26555: ignore NULL link key 145- CVE-2020-26558: abort LE Secure Connection pairing if remote uses the same public key 146 147## Release v1.4 148 149### Added 150- HCI: `btstack_transport_sco.h` supports SCO over physical PCM/I2S interface (`HAVE_SCO_TRANSPORT`) 151- POSIX: `btstack_transport_sco_i2s_test_bridge.c` implements SCO transport interface for UART-to-I2S test bridge 152- btstack_uart: `btstack_uart_t` interface extends `btstack_uart_block_t`: 153 - support sending and receiving SLIP frames for HCI H5 154 - support odd parity 155 - `hci_transport_h4` and chipset drivers have new functions to provide `btstack_uart_t` 156- btstack_uart_slip_wrapper: wrapper that implements SLIP functionality for existing `btstack_uart_block` drivers. 157- hci_transport: add parity field and pass on to `btstack_uart_t` in h4 and h5 158- GATT Client: Battery Service Client 159- GATT Client: Device Information Service Client 160- GATT Client: HID-over-GATT (HOG) Client, Report and Boot Host 161- GATT Client: Scan Parameters Service Client 162- GATT Server: Scan Parameters Service Server 163- GAP: support scan page configuration with `gap_set_page_scan_activity` and `gap_set_page_scan_type` 164- GAP: support sniff subrating with `gap_sniff_subrating_configure` 165- GAP: support QoS setup with `gap_qos_set` 166- AVRCP: new field `button_pressed` in `AVRCP_SUBEVENT_OPERATION` 167- AVRCP: `AVRCP_SUBEVENT_OPERATION` emitted for button release 168- AVRCP Controller: `avrcp_controller_start_press_and_hold_cmd` supports arbitrary device buttons 169- AVRCP Controller: reassemble fragmented AVCTP packets 170- AVDTP: `avdtp_register_media_config_validator` allows to validate media codec configuration 171- A2DP Source: `ENABLE_A2DP_SOURCE_EXPLICIT_CONFIG` disables auto config. requires call to `a2dp_source_set_config_{CODEC}` 172 173### Fixed 174- GAP: calculate IO Cap AuthReq Bondable Mode based on `gap_ssp_set_authentication_requirement` and `gap_set_bondable_mode` 175- GAP: only store link key for SSP if remote side has set bondable in io cap auth requirements 176- GAP: allow to disable link supervision timeout 177- GAP: fix `gap_connect` after `gap_connect_cancel` 178- GAP: re-configure advertisements after power cycle 179- HCI: handle start inquiry failure 180- L2CAP: fix create outgoing connection triggered from packet handler on hci disconnect event 181- L2CAP: return unknown mandatory option in config response 182- AVDTP: fix spelling `avdtp_set_preferred_sampling_frequency` 183- AVRCP Target: fix notification changed event 184- HFP: Emit audio connection released on SLC Release, e.g. on remote power off 185- HFP HF: fix audio connection setup if codec negotiation is supported 186- HFP HF: only emit single event for RING and AG Status updates 187- HFP AG: fix audio connection setup for in-band ringtone on incoming connection 188 189### Changed 190- Port Archive: moved ports that are not recommended for new designs to port/archive folder: 191 - MSP430: the ports used the older community GCC version without 20-bit support needed for code size > 64kB 192 - Broadcom/Cypress H5: uploading PatchRAM is only possible in H4 mode. It's better to also use H4 in general 193 - PIC32-Harmony: the port used Harmony v1 while Harmony v3 has been out since a while 194 - iOS: not supported 195- Run Loop Base: functionality used in most platform run loop implementations 196 - code from `btstack_run_loop_base.c` moved into `btstack_run_loop.c` to minimize changes to build systems 197 - `btstack_run_loop_base.c` is a placeholder and can be removed from build 198- HCI Dump: replace monolithic `hci_dump.c` (with many #ifdefs) into dispatcher with platform-specific implementations: 199 - `posix/hci_dump_posix_fs` - writes binary log file 200 - `posix/hci_dump_stdout` - log to console using printf with local system time 201 - `embedded/hci_dump_embedded_stdout` - log to console using printf 202 - `embedded/hci_dump_segger_stdout` - log to RTT console using `SEGGER_printf` 203 - `embedded/hci_dump_segger_binary` - writes binary log over RTT to host 204- HCI: config I2S for BCM Controllers if `ENABLE_SCO_OVER_PCM`, reduce bit clock to 256/512 kHz 205- btstack_uart_posix: supports SLIP frames and replaces `btstack_uart_block_posix` 206- hci_transport_h5: more performant H5 implementation that requires `btstack_uart_t` driver with SLIP support 207- POSIX Ports: use new `btstack_uart_posix` implementation 208- posix-h5/posix-h5-bcm: use even parity for UART 209- HCI Transport: extract convenience function declaration for h4, h5, em9304_spi, and usb into separate hci_transport_{type}.h 210- GAP: provide Device ID from EIR in GAP_EVENT_INQUIRY_RESULT 211- GAP: only store link key if it allows requested security level 212- GAP: abort SSP pairing if MITM protection required but not possible 213- SM: start pairing as Central for already encrypted connection on Slave Security Request 214- GATT Client: Use ATT_READ_REQUEST for first blob of Read Long Characteristic and Read Long Characteristic Descriptor 215- GATT Server: Allow ATT Read Callback to return custom ATT Error Code 216- Nordic SPP Service Server: use `GATTSERVICE_SUBEVENT_SPP_SERVICE_CONNECTED` and `GATTSERVICE_SUBEVENT_SPP_SERVICE_CONNECTED` 217 events instead of callback, and `RFCOMM_DATA_PACKET` for received data 218- u-blox SPP Service Server: use `GATTSERVICE_SUBEVENT_SPP_SERVICE_CONNECTED` and `GATTSERVICE_SUBEVENT_SPP_SERVICE_CONNECTED` 219 events instead of callback, and `RFCOMM_DATA_PACKET` for received data 220- HID: Move `src/classic/hid.h` into `src` and prefix with `btstack_` to use it with BLE and avoid name clashes 221- HFP: provide acl_handle in events to identify connection 222- HSP AG: emit HSP_SUBEVENT_BUTTON_PRESSED instead of audio connection setup/release 223- Example: use `btstack_event.h` getters instead of direct array access, use enum to compare status codes 224 225 226## Release v1.3.2 227 228### Added 229- GAP: support for Classic Out-of-Band (OOB) pairing via `gap_ssp_remote_oob_data` with `ENABLE_CLASSIC_OOB_PAIRING` 230- GAP: read local OOB data on start and on call to `gap_ssp_generate_oob_data`, provided via `GAP_EVENT_LOCAL_OOB_DATA` 231- HID Host: add profile, update `hid_host_demo.c` example 232 233### Fixed 234- L2CAP: make handling of HCI disconnect more robust 235- AVDTP: emit stream release for active stream if signaling connection is closed first, e.g. caused by HCI disconnect 236- AVRCP: fix issue when Controller and Target send at the same time 237 238### Changed 239- A2DP, AVDTP: use `a2dp_source_set_config_{TYPE}` and `avdtp_config{TYPE}_store` to avoid large number of parameters 240 241 242## Release v1.3 243 244### Added 245- CC256x: with ENABLE_CC256X_ASSISTED_HFP, HFP enables WBS codec on demand and configures PCM/I2S interface for 8kH/16kHz 246- BCM: with ENABLE_BCM_PCM_WBS, HFP enables WBS codec on demand and configures PCM/I2S interface for 8kH/16kHz 247- SDP Client RFCOMM: add `sdp_client_query_rfcomm_channel_and_name_for_service_class_uuid` 248- HFP: `ENABLE_HFP_AT_MESSAGES` lets HFP emit `HFP_SUBEVENT_AT_MESSAGE_SENT` and `HFP_SUBEVENT_AT_MESSAGE_RECEIVED` 249- A2DP, AVDTP: provide capabilities and configuration events for A2DP codecs: SBC, MPEG Audio, MPEG AAC, ATRAC 250- A2DP + AVDTP Source: allow to send media packet with `avdtp_source_stream_send_media_packet` and `a2dp_source_stream_send_media_packet` 251- A2DP + AVDTP Source: add `avdtp_source_stream_send_media_payload_rtp` and `a2dp_source_stream_send_media_payload_rtp` 252- A2DP Source: emit `A2DP_SUBEVENT_SIGNALING_CAPABILITIES_COMPLETE` 253- A2DP Source: allow to configure endpoints by calling `a2dp_source_set_config_{TYPE}` during SEP discovery with SBC fallback 254 255### Fixed 256- HCI: keep `le connecting request` on connection complete active, fixes gap_auto_connection_stop() + gap_auto_connection_start() 257- L2CAP: fix packet size check for incoming classic basic channels (regression introduced in v1.2.1) 258- HFP AG/HSP AG: avoid connecting to remote service with same role 259- A2DP Source: support multiple Stream Endpoints with different Media Codec types 260- A2DP Source: emit codec configure event with reconfigure flag set on reconfigure 261- GATT Compiler: support multiple instances of the same service 262 263### Changed 264- GAP: provide Link Type parameter to incoming connection filter for `gap_register_classic_connection_filter` 265- HFP/GOEP Client/AVDTP/A2DP: return `SDP_SERVICE_NOT_FOUND` if no suitable SDP record is found 266- AVDTP Source: `avdtp_source_stream_send_media_payload` includes SBC Header and was deprecated 267- AVDTP/A2DP: use `avdtp_channel_mode_t` in `A2DP_SUBEVENT_SIGNALING_MEDIA_CODEC_SBC_CONFIGURATION` 268- A2DP: fix events and use `a2dp_cid`, `local_seid,` `remote_seid` field names in A2DP sub-events 269- GATT Client: Skip MTU exchange after MTU exchange on ATT Server 270- Ports: STM32-F103RB Nucleo + CC256x port removed 271- ESP32: enabled HFP Wide-Band Speech, disable classic secure connections in HSP/HFP demos 272 273 274## Release v1.2.1 275 276### Fixed 277- L2CAP: use connection handle for channel lookups 278- L2CAP: forward data only in open state 279 280### Changed 281- L2CAP: check packet size against local mtu for classic basic channels 282 283 284## Release v1.2 285 286### Fixed 287- L2CAP: trigger pairing for outgoing LE Data Channels if security level insufficient 288- SM: fix update of sc flag for re-encrypted connection in peripheral role 289- SM: send security request on re-connect if bonded and `ENABLE_LE_PROACTIVE_AUTHENTICATION` is defined 290- ESP32: fix audio sink driver 291 292### Added 293- GAP: `gap_delete_bonding` removes device from LE Resolving List and from discards LE bonding information 294- GATT Client: delete bonding information if re-encryption fails and `ENABLE_LE_PROACTIVE_AUTHENTICATION` is not defined 295- GATT Client: gatt_client_set_required_security_level() allows to set required minimum security level for all GATT requests 296- SM: emit events for re-encryption started/complete when bonding information is available 297 298### Changed 299- AVRCP Controller: allow to send multiple absolute volume commands without waiting for response. 300- GAP: replaced `ENABLE_LE_CENTRAL_AUTO_ENCRYPION` with `ENABLE_LE_PROACTIVE_AUTHENTICATION` 301 302 303## Changes October 2020 304 305### Fixed 306- AVDTP Initiator: avoid use of remote seid for stream endpoint lookup, fixes issue with two connected devices 307- AVDTP Source: buffer for SBC media codec information got discarded, leading to invalid Set Configuration command in second connection 308- SM: only trigger Cross-Transport Key Derivation (CTKD) when bonding is enabled 309- SM: set LinkKey flag to request CTKD if enabled 310- SM: store CTKD key with Public Identity Address 311- SM: only allow CTKD to overwrite existing link key if derived key has same or higher authentication 312- SM: start SMP Timeout when sending Security Request 313- HFP HF: fix response to AG Codec Selection while waiting for OK of parallel command 314- HCI: fix reject of LE remote connection param request via HCI 315 316### Added 317- GAP: add `gap_get_link_key_for_bd_addr` 318- GAP: add `gap_bonded` to check if bonding information is available for active connection 319- SM: support h7 for CTKD 320 321### Changed 322- SM: Cross-Transport Key Derivation requires `ENABLE_CROSS_TRANSPORT_KEY_DERIVATION` now 323- SM: block connection if encryption fails for bonded devices as Central 324- SM: support pairing as Central after failed re-encryption 325 326 327## Release v1.1 328 329### Fixed 330- AVRCP/AVCTP: report AVRCP 1.6 and AVCTP 1.4 in SDP record 331 332### Added 333 334### Changed 335 336 337## Changes September 2020 338 339### Fixed 340- HFP: fix parsing of ranges e.g. in +CIND responses 341- AVDTP, AVRCP: fix bugs due to transaction id overrun 342- A2DP Source: fix issues with stream configuration by sink 343- hci_dump: fix tv_us calculation for non-posix / embedded systems with binary output 344 345### Added 346- `btstack_ring_buffer`: add `btstack_ring_buffer_reset` to reset it to initial state/empty 347- GAP: Support for address resolution of resolvable private addresses by Controller with `ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION` 348 349### Changed 350- AVDTP, AVRCP, HSP: schedule SDP query, avoids avoids 'command disallowed' if SDP client is busy 351- HSP, HFP: allow to configure usable SCO packet types 352- cc256x: update CC256xC init script to v1.4 353- A2DP Source: use Get All Capabilities if supported by remote get Delay Reporting capability 354 355## Changes August 2020 356 357### Fixed 358- ESP32: fix authentication for incoming Secure Connections 359- AVDTP: Fix forwarding of Delay reports 360- STM32-F4Discovery: fix pan_lwip_http_server by increasing HCI_ACL_PAYLOAD_SIZE 361- tool/create_packet_log: basic support for 16-bit Unicode log files from Windows 362 363### Added 364- `btstack_run_loop_base`: added `btstack_run_loop_base_dump_timer` 365- GAP: request role change for classic connection via `gap_request_role` 366- GAP: LE Whitelist API with `gap_le_whitelist_x` with x = add, remove, clear and new `gap_connect_with_whitelist` 367- SDP Client: add sdp_client_register_query_callback() allows to register query request instead of polling sdp_client_ready() 368- BNEP lwIP: add `bnep_lwip_connect` to establish BNEP connection and manage lwIP network interface 369- New `btstack_linked_queue` utility, a linked list-based queue with first-in-first-out semantics and constant time enqueue/dequeue operations 370- btstack_tlv_posix: add `btstack_tlv_posix_deinit` 371- New `btpclient` for use with [auto-pts project](https://github.com/intel/auto-pts) 372 373### Changed 374- GAP: treat AES-CCM encrypted connection as mutually authenticated (BIAS) 375- GAP: 'gap_auto_connect_x' API deprecated. Please directly manage LE Whitelist with `gap_le_whitelist_*` functions and call `gap_connect_with_whitelist` instead 376- example/hid_host_demo: try to become master for incoming connections 377- btstack_run_loop: use btstack_assert instead of local while(true) 378- att_db_util: allow to reset att_db via `att_db_util_init` 379 380## Changes July 2020 381 382### Fixed 383- AVDTP: fix invalid response for Get Capabilities request if Delay Reporting was supported 384- AVDTP: handle concurrent signaling establishment with reject and retry 385 386### Added 387- example/hid_host_demo: support reconnect from HID device 388- Crypto: support software AES128 for AES-CCM operations 389- AVRCP: introduced AVRCP_FEATURE_MASK_* as alternative to avrcp_controller_supported_feature_t and avrcp_target_supported_feature_t enums 390- btstack_audio: add set_volume() to sink and set_gain() to source interfaces, minimal volume control for portaudio playback 391- AVDTP: renamed definition of supported features from AVDTP_SOURCE_SF_ and AVDTP_SINK_SF_ to AVDTP_SOURCE_FEATURE_MASK_ and AVDTP_SINK_FEATURE_MASK_ respectively 392- GAP: Provide gap_get_role to query master/slave role for HCI connection handle 393- GAP: Provide gap_pin_code_response_binary to use binary data as PIN, e.g. for pairing with Nintendo Wii Remote 394 395### Changed 396- GAP: set minimum required encryption key size for Classic connections back from 16 to 7, matching the Core spec 397 398 399## Changes June 2020 400 401### Fixed 402- HFP: Fix parsing of empty fields, e.g. phone number in +CLCC and other AT commands 403- SM: Fix validation of confirm value for secure connection Passkey entry 404- AVRCP: handle concurrent signaling establishment with reject and retry 405 406### Added 407- GAP: Detect Secure Connection -> Legacy Connection Downgrade Attack by remote features and actual encryption type (BIAS) 408- GAP: Mutual authentication: request authentication after Classic connection got encrypted (BIAS) 409- Windows port for Dialog DA14585 connected via serial port 410 411## Changes 412- CVSD PLC: treat zero frames as good and allow to mark data as bad, e.g. if reported by Controller as erroneous 413 414## Changes May 2020 415 416### Fixed 417- hfp_hf, hsp_hs: use eSCO params in accept sco connection only for incoming eSCO connections 418- pbap_client: fix PBAP UUID len on connect message 419- SM: fix secure connection pairing as peripheral when local user confirmation happens after remote one 420- A2DP Source: only connect to remote sink stream endpoints 421- btstack_hal_flash_memory: fix write of 0xff bytes to simulated flash 422- hsp_hs: fix disconnect if audio not connected 423- hsp_ag: fix accept incoming connection 424 425### Added 426- example/le_mitm: MITM implementation that forwards ATT PDUs and allows for pairing 427- GAP: gap_set_security_level sets required security level for incoming and outgoing connections 428- cc256x: allow to specify power vector for each modulation type 429- FreeRTOS: btstack_run_loop_freertos_trigger_exit allows to request run loop exit 430- SM: support LE Secure Connections Only mode with sm_set_secure_connections_only_mode 431- GAP: enable BR/EDR Secure Connections if supported, add gap_secure_connections_enable 432 433### Changed 434- L2CAP ERTM: send extended features request only once per HCI connection 435 436 437## Changes April 2020 438 439### Fixed 440- hog_mouse_demo/hog_keyboard_demo: handle set protocol mode = boot protocol mode 441- HCI: only update BD_ADDR placeholder in shortened and complete name in EIR data, limit device name to 240/248 bytes 442 443### Added 444- GAP: gap_set_allow_role_switch allows to prevent role switch in outgoing classic ACL connections 445- example: hog_boot_host_demo implements an HID-over-GATT Boot Host that supports keyboard and mouse 446- HCI: add ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS that forces fragmentation of ACL-LE packets to fit into over-the-air packet 447 448### Changed 449- Broadcom/Cypress: wait 300 ms after PatchRAM update in hci.c to assert Controller is ready 450- esp32: provide esp-idf/component/btstack/btstack_port_esp32.c and only minimal app_main in template/main/main.c 451- att_db: skip att_read_callback for ATT Read Blob Request if offset == value_len 452 453 454## Changes March 2020 455 456### Fixed 457- GAP: fixed gap_set_scan_parameters() if issued right before gap_start_scan() 458- HCI: only send HCI Read Local Encryption Key Size if supported by Controller 459 460### Added 461- GATT Client: allow to register for any notification/indication and/or any connection 462- HCI: added hci_read_inquiry_scan_activity and hci_write_inquiry_scan_activity commands 463- chipset: assert hci packet buffers are suitable for firmware upload or patches (atwilc3000,bcm,cc256x,intel) 464- btstack_util: added btstack_replace_bd_addr_placeholder 465 466### Changed 467- AVRCP Target: volume in avrcp_target_volume_changed is reported as current value in interim response to register for volume change notifications 468- SDP Client: query attributes 0x0000..0xffff instead of 0x0001..0xffff to match other stacks / improve compatibility with bad sdp server implementations 469 470 471## Changes Februar 2020 472 473### Fixed 474- AVRCP Target: fix reporting of PLAYBACK_STATUS_CHANGED 475- HCI: handle reconnect request for Classic and LE connections triggered by packet handler for Disconnection Complete Event 476 477### Changed 478- hid_host_mode: allow sniff mode 479 480### Added 481- port/qt-usb and port/qt-h4: integrate BTstack Qt run loop for Unix- and Win32-based Qt application connected to Bluetooth module via H4 over serial port or USB 482 483 484## Changes January 2020 485 486### Fixed 487- L2CAP ERTM: avoid read-after-free on decline of incoming connection 488- GATT Client: set uuid16 to zero when deserializing uuid128 services, characteristics, and descriptors 489- att_db_util: fix realloc of att db buffer for large attributes 490- btstack_tlv_posix: only keep last value in memory, fix delete operation 491- l2cap_signaling: use packet boundary flags 0x00 for LE signaling packets (ignoring hci_non_flushable_packet_boundary_flag_supported()) 492 493### Added 494- att_db_util: provide GATT Database Hash via att_db_util_hash_calc 495- GATT Compiler: provide GATT Database Hash via GATT_DATABASE_HASH Characteristic 496- ATT Server: validate request pdu length 497 498### Changed 499- Crypto: update AES-CMAC implementation to access all message bytes sequentially 500 501 502## Changes December 2019 503 504### Fixed 505- example/pan_lwip_http_server: use Network Access Point, CoD 506- sm: emit pairing complete in master role when no keys are distributed / bonding disabled 507 508### Added 509 510### Changed 511- Updated CC256x initscript: CC256xC v1.3 512- ESP32: add CMake project files 513 514 515## Changes November 2019 516 517### Fixed 518- AVDTP Source: return correct `avdtp_cid` and `local_seid` in `AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW` 519- L2CAP: send LE Data Channel SDUs round robin with other data 520- L2CAP ERTM: send ERTM I-frames round robin with other data 521 522### Added 523- ATT Server: return error if request to send now for Notification or Indication already registered 524- Linked List: return if item was added for `btstack_linked_list_add[_tail]` 525- btstack_run_loop_remove: return bool true if timer/data source was removed 526- segger-rtt: allow to configure with `SEGGER_RTT_PACKETLOG_*` directives, update to v6.54 527- GAP: support setting Link Supervision Timetout for outgoing Classic connections using `gap_set_link_supervision_timeout` 528- lwip: add download test files to http server demo 529 530### Changed 531- Linked List: return bool true if item was removed 532 533 534## Changes October 2019 535 536### Fixed 537 538### Added 539- `btstack_bool.h`: provide boolean type 'bool' via `<stdbool.h>` or as backport 540- provide `btstack_assert(condition)` 541- H4 Transport: avoid calling `hci_transport_h4_trigger_next_read` when transport is closed 542 543### Changed 544- libusb and posix ports: store bonding information in TLV 545 546 547## Changes September 2019 548 549### Fixed 550- L2CAP ERTM: assert that packet can be stored in fragment buffers in ertm 551- L2CAP ERTM: reject incoming connection if ERTM is configured as mandatory but not supported by remote 552- GATT Client: allow Write Without Response independent of other requests 553 554### Added 555- GAP: allow to reject GAP classic connection via gap_register_classic_connection_filter 556- GAP: support reading RSSI for Classic+LE using gap_read_rssi. Emits `GAP_EVENT_RSSI_MEASUREMENT` 557 558### Changed 559- Bluetooth and BTstack Error Codes and Events: collect status codes in bluetooth.h and events in btstack_defines.h 560- bluetooth.h: extract internal defintitions to respective protocol layers 561- Updated CC256x initscripts (CC256xB v1.8, CC256xC v1.2, CC256xC v1.2) 562 563 564## Changes August 2019 565 566### Fixed 567- POSIX, WICED, Windows, FreeRTOS run loops: handle time_ms overrun after 49 days 568- RFCOMM: accept incoming L2CAP connection in Basic mode if ERTM is enabled but not requested for this connection 569- RFCOMM: limit RFCOMM MTU by local L2CAP MTU for outgoing connections (only revelvant for ERTM) 570- L2CAP ERTM: stop timers on disconnect 571- L2CAP ERTM: fix sending of segmented SDUs 572- L2CAP ERTM: handle unsupported Information Response 573- SM: generate local nonce for confirm value in JW+NC+PK in Secure Connections Responder role 574 575### Added 576- `btstack_run_loop_base`: portable implementation of timer and data source management as base for platform specific implementations 577 578## Changed 579- FreeRTOS: use xQueueCreateStatic (static variant of xQueueCreate) if available for static memory-only setups 580- L2CAP ERTM: handle invalid Information Response (assume no extended features supported) 581- POSIX: use monotonic clock as timebase if available 582- HCI Transport H4/H5/EM9304 SPI: ignore block read/sent from UART driver when closed 583- HCI: Read Encryption Key Size after encryption was enabled 584- Errata 11838: 585 - GAP: gap_set_required_encryption_key_size allows to set the required key size, default = 16 (max) 586 - GAP: validate encryption key size to emit GAP Security Levels 587 588## Changes July 2019 589 590### Fixed 591- SM: Fixed regression introduced in f3582630 592- L2CAP: avoid reading l2cap signaling command len out of bounds 593- HCI Transport H4/H5/EM9304 SPI: fix payload size checks (also for 8/16-bit platforms) 594 595### Changed 596- SM: Start encryption upon receiving slave securiy request if bonded 597- hci: use 2 as HCI_INCOMING_PRE_BUFFER_SIZE in LE-only configuration for GATT Client 598 599--- 600 601## Changes June 2019 602 603### Changed 604- FreeRTOS: use freertos/.. prefix to include FreeRTOS headers if HAVE_FREERTOS_INCLUDE_PREFIX is defined 605- BNEP: add Connection Handle to BNEP_EVENT_CHANNEL_OPENED 606- Examples: renamed le_counter to gatt_counter and le_streamer to le_streamer_server to indicate suppport for GATT over BR/EDR 607 608### Fixed 609- BNEP: Bluetooth address is stored in little-endian format for all BNEP_EVENT_* 610- libusb: avoid use-after-free for SCO packets on disconnect 611 612### Added 613- example: pan_lwip_http_server using lwIP as network stack to implement PAN NAP service 614- platform/lwip/bnep_lwip.c: BNEP lwIP adapter that forwards packets between BNEP service and lwIP 615- ENABLE_GATT_OVER_CLASSIC enables support for GATT over BR/EDR in att_server 616 617--- 618 619## Changes May 2019 620 621### Changed 622- ESP32: Configure SCO over HCI after power up 623- btstack_tlv_flash_bank: support targets where a value cannot be overwritten with zero. When ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD 624 is defined, an explicit delete field is used to indicate an invalid entry. 625 626### Fixed 627- SM: Avoid potential use-after-free on immediate disconnect (lookup connection via con handle instead of storing pointer) 628 629### Added 630- gatt_client: emit query complete event for signed write operation 631- hci_transport_h4: add workaround for flow control bug in CYW2070x, enable with ENABLE_CYPRESS_BAUDRATE_CHANGE_FLOWCONTROL_BUG_WORKAROUND 632 633--- 634 635## Changes April 2019 636 637### Changed 638- ESP32: use micro-ecc from 3rd-party as esp-idf removed it in their 3.3 release 639 640### Fixed 641- hci: pad LE Scan response with zeroes 642- SM: store local CSRK 643- ATT DB: call write callback for validated signed writes 644- ATT Server: abort signed write validation on incoming new request 645- Bluetooth SIG web scraping tools updated 646- libusb: compiles for FreeBSD 647 648### Added 649 650--- 651 652## Changes March 2019 653 654### Changed 655- use Makefile for stm32-f4discovery-cc256x port 656- le_device_db: add secure_connection argument to le_device_db_encryption_set and le_device_db_encryption_get 657 658### Fixed 659- SM: Use provided authentication requirements in slave security request 660 661### Added 662- port/stm32-f4discovery-cc256x: add support for built-in MEMS microphone 663- SM: Track if connection encryption is based on LE Secure Connection pairing 664- ATT DB: Validate if connection encrypted is based on SC if requested 665- att_db_util: support ATT_SECURITY_AUTHENTICATED_SC permission flag 666- GATT Compiler: support READ_AUTHENTICATED and WRITE_AUTHENTICATED permsission flags 667- ESP32: erase nvs flash is newer nvs version found 668- libusb: add support for nRF52840-PCA10056 running Zephyr hci_usb example 669- port/stm32-l073rz-nucleo-em9304 for Nucleo L073RZ with EM9304 DVK, replaces port/stm32-l053r8-nucleo-em9304 670 671## Changes February 2019 672 673### Changed 674- example/a2dp_sink_demo: use linear resampling to fix sample rate drift 675- btstack_audio: split interface into sink and source 676 677### Fixed 678- Crypto: fix lockup when stack is shutdown while waiting for result of HCI Command, e.g. LE Read Local P256 Public Key 679- SM: Avoid SM_EVENT_PAIRING_COMPLETE with ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION after successful pairing in responder role 680 681### Added 682- example/a2dp_sink_demo: add target role, support volume control on both devices 683- example/audio_duplex: playback audio audio source on audio sink (test audio path) 684- btstack_audio_embedded: implement audio source path 685 686--- 687 688## Changes January 2019 689 690### Changed 691- L2CAP: provide channel mode (basic/ertm) and fcs option in L2CAP_EVENT_CHANNEL_OPENED 692- RFCOMM: support L2CAP ERTM. Callbacks passed to rfcomm_enable_l2cap_ertm() are used to manage ERTM buffers 693 694### Added 695- L2CAP: emit L2CAP_EVENT_ERTM_BUFFER_RELEASED if ERTM buffer not needed/used anymore 696- L2CAP: add fcs_option to ERTM config l2cap_ertm_config_t 697- HCI: validate advertisement data length field when generating GAP_EVENT_ADVERTISING_REPORT 698- ad_parser: validate data element length fields in ad_iterator_has_more 699- Raspberry Pi 3 A+/B+ port in port/raspi, starts without power cycle 700 701### Fixed 702- HCI: release outgoing buffer on disconnect if waiting to send another ACL fragment 703- POSIX: use correct baudrate enums for baud rates higher than 921600 (Linux) 704- Crypto: directly process queued crypto operation on HCI result 705 706--- 707 708## Changes December 2018 709 710### Added 711- SM: generate and store ER / IR keys in TLV, unless manually set by application 712- hci_dump: support PacketLogger or BlueZ format output via SEGGER RTT Channel 1 Up 713 714### Fixed 715- SM: fix internal buffer overrun during random address generation 716 717## Changes November 2018 718 719### Added 720- GAP: gap_le_connection_interval provides connection interval for conn handle 721- Nordic SPP Service Server: GATT service that emulates a serial port over BLE based on Nordic Semiconductor documentation. 722- uBlox SPP Service Server: GATT service that emulates a serial port over BLE based on uBlox documentation. 723- SM: ENABLE_LE_CENTRAL_AUTO_ENCRYPTION triggers automatic encryption on connect to bonded devices 724- SM: generate and store ER / IR keys in TLV, unless manually set by application 725 726### Fixed 727- SM: prevent random address updates if gap_random_address_set was used 728- SM: fix internal buffer overrun that can cause storing of bonding information to fail 729- SM: ignore Slave Security Request after sending own Pairing Request 730- L2CAP: fix use after free on disconnect if ERTM is enabled 731- HFP: Handle multiple commands/responses in single RFCOMM packet 732- Memory Pools: clear all buffers before use 733 734--- 735 736## Changes October 2018 737 738### Added 739- SDP Server: queue incoming connections when already connected instead of rejecting them 740- GAP: Support enter/exit sniff mode via gap_sniff_mode_enter/exit. gap_set_default_link_policy_settings is needed to enable sniff mode in general. 741- HIDS Device: GATT service that exposes HID reports intended for HID Devices, like keyboard and mouse. 742 743### Fixed 744- HCI: fix bug in gap_inquiry_stop that triggered additional GAP_EVENT_INQUIRY_COMPLETE instead of stopping the inquiry 745- L2CAP: fix issue with outgoing connection before read remote supported complete when other channels exist 746- L2CAP ERTM: allow SDU of szie MPS in first packet that contains L2CAP SDU Length 747- L2CAP ERTM: fix memory corruption triggered if local_mtu > mps 748- L2CAP ERTM: fix outgoing fragment management 749- HFP: decline incoming RFCOMM connection after outgoing connection was started 750- AVRCP: fix crash on disconnect of connection established by remote 751 752--- 753 754## Changes September 2018 755 756### Fixed 757- HCI: Error creating outgoing connection (e.g. Connection Limit Exceeded) now handled 758- L2CAP: Error creating outgoing connection (e.g. Connection Limit Exceeded) now handled 759- L2CAP: Evaluate 'can send now' on HCI Disconnect as ACL buffers in Bluetooth Controller have been used for the closed connection are freed implicitly 760- L2CAP: Check can send now before sending extended information requeste needed for ERTM mode 761- L2CAP: Use valid signaling identifier for L2CAP Connection Parameter Update Request 762- RFCOMM: Trigger l2cap request to send on rfcomm credits when client is waiting to sendtrigger l2cap request to send on rfcomm credits when client is waiting to send 763- RFCOMM: Avoid use-after-free on channel finalize 764- GATT Client: stop timer on disconnect - fixes use after free / crash 765 766### Added 767- A2DP Source: Support stream reconfiguration (a2dp_source_reconfigure_stream_sampling_frequency) 768- 3rd-party: yxml is used for PBAP vCard list parsing 769- cc256xC: new v1.1 init scripts 770 771--- 772 773## Changes August 2018 774 775### Added 776- PBAP: added pbap_get_phonebook_size() to get phonebook entry count 777 778### Fixed 779- GATT Server: Allow enable Notifications/Indication with Write Command. Fixes issue with some Android devices. 780- SM: fix pairing for Secure Connections with Bonding if remote sends additional keys 781- SM: drop LTK flag from Pairing Response for Secure Connections 782- L2CAP: fix emitted L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_REQUEST 783 784## Changes June 2018 785 786### Added 787- btstack_audio.h: application level API for audio playback and recording 788- embedded/hal_audio.h: low-level API for audio playback and recording 789- HID Device: hid_device_connect(..) function 790- ESP32: implement hal_audio 791- DA14585: support for Dialog Semiconductor DA14585 LE-only controller 792- Raspberry Pi 3 + Raspberry Pi Zero W port in port/raspi 793 794### Changed 795- Errata 10734: 796 - SM: Generate new EC Public Keypair after each pairing 797 - SM: Abort failure with DHKEY_CHECK_FAILED if received public key is invalid (instead of unspecified error) 798- btstack.h: only include classic headers if ENABLE_CLASSIC is defined 799- windows: ignore virtual Bluetooth adapter provided by VMware 800- Replaced HCI_PACKET_BUFFER_SIZE with HCI_INCOMING_PACKET_BUFFER_SIZE and HCI_OUTGOING_PACKET_BUFFER_SIZE 801 802--- 803 804## Changes June 2018 805 806### Fixed 807- HFP: Fix Wide Band Speech bit in SDP record for both HF/AG. Missing bit prevents macOS from using mSBC 808- ATT Server: send ATT_EVENT_HANDLE_VALUE_INDICATION_COMPLETE with status ATT_HANDLE_VALUE_INDICATION_DISCONNECT on disconnect 809- AVRCP Controller: fix parsing of now playing info 810 811### Changed 812- ATT Server: ATT_HANDLE_VALUE_INDICATION_DISCONNECT is delivered to service handler if registered 813 814### Added 815- ATT Server: packet handler field added to att_service_handler_t to receive: connect/disconnect, atu exchange, indication complete 816 817--- 818 819## Changes May 2018 820 821### Added 822- GAP: re-encrypt outgoing connection if bonded 823- ATT Server: wait until re-encryption is complete 824- GATT Client: wait until re-encryption is complete 825- ATT Server: added att_server_request_to_send_notification and att_server_request_to_send_indication 826- GATT Client: if ENABLE_GATT_CLIENT_PAIRING, GATT Client starts pairing and retry operation on security error 827 828### Changed 829- ATT Server: att_server_register_can_send_now_callback is deprecated, use att_server_request_to_send_notification/indication instead 830 831### Fixed 832- SM: Fix LE Secure Connection pairing in Central role 833- le_device_db_tlv: fix seq nr management 834- SM: improve le_device_db lookup and storing of IRK 835- GATT Server: fix lookup for Client Characteristic Configuration in services with multiple Characteristics 836- RFCOMM: emit channel closed on HCI/L2CAP disconnect after sending DISC while expecting UA 837 838--- 839 840## Changes April 2018 841 842### Added 843- Crypto: btstack_crypo.h provides cryptographic functions for random data generation, AES128, EEC, CBC-MAC (Mesh) 844- SM: support pairing using Out-of-Band (OOB) data with LE Secure Connections 845- Embedded: support btstack_stdin via SEGGER RTT 846 847### Changed 848- att_db_util: added security requirement arguments to characteristic creators 849- SM: use btstack_crypto for cryptographpic functions 850- GAP: security level for Classic protocols (asides SDP) raised to 2 (encryption) 851 852### Fixed 853- HFP: fix answer call command 854- HCI: fix buffer overrun in gap_inquiry_explode 855- SDP: free service record item on sdp_unregister_service 856 857## Changes March 2018 858 859### Added 860- GAP: allow to limit number of connections in LE Peripheral role with gap_set_max_number_peripheral_connections 861- ATT Server: support for delayed ATT read response, see example/att_delayed_read_response.c 862- ATT Server: allow to specify security requirements seperately for read/writes. .h files need to be regenerated 863 864### Fixed 865- RFCOMM: fix infinite loop on L2CAP connection error (regression from 4c3eeed1) 866- HSP HS: accept incomming SCO connection 867- SM: fix iteration over LE Device DB entries for bonding and address resolving 868- SM: store pairing information only if both devices have requested bonding 869 870--- 871 872## Changes February 2018 873 874### Added 875- GATT Client: gatt_client_request_can_write_without_response_event() causes GATT_EVENT_CAN_WRITE_WITHOUT_RESPONSE 876- SM: new event SM_EVENT_PAIRING_COMPLETE 877- GAP: support iteration over stored Classic link keys: gap_link_key_iterator_init, gap_link_key_iterator_get_next, gap_link_key_iterator_done 878- GAP: add gap_delete_all_link_keys 879 880### Changed 881- GATT Client: round robin for multiple connections 882- ATT Dispatch: round robin for ATT Server & GATT Client 883- L2CAP: round robin for all L2CAP channels (fixed and dynamic) 884- btstack_link_key_db: addition functions for link key iteration 885- GAP: LE scanning enabled not reset on HCI Reset -> can be enabled before HCI Power Up 886- CSR: set all keys in psram instead of default 887 888### Fixed 889- tc3556x: fix startup after baud rate change 890 891--- 892 893## Changes January 2018 894 895### Added 896- Port for Windows with Zephyr HCI Firmware connected via serial port 897- em9304: upload patch containers during HCI bootup 898- Makefile for STM32-F4Discovery port 899- support for console out via SEGGER RTT 900- LE Data Channels example in BTstack and [iOS example on GitHub](https://github.com/bluekitchen/CBL2CAPChannel-Demo) 901- LE Streamer Client can send as fast as possbile as well 902- L2CAP: option to limit ATT MTU via l2cap_set_max_le_mtu 903 904### Changed 905- HCI: allow to set hci_set_master_slave_policy (0: try to become master, 1: accept slave) 906- GAP: gap_set_connection_parameters includes scan interval and window params 907- GATT Client: GATT_EVENT_MTU indicates max MTU 908- ATT DB Util: attribute handle is returned for new Services and Characteristics 909 910### Fixed 911- Windows: retry serial port operations if not all bytes have been read/written 912- HFP: avoid buffer overflows setting up messages 913- SBC Decoder: improved error handling for invalid SBC audio data 914- GAP: fix Connection Parameter Response in Central role 915- ATT DB Util: update pointer to database in case of realloc 916- GATT Client: set UUID16 field if 16-bit UUID is stored as UUID128 917- GAP: release HCI Connnection after gap_le_conne 918- ATT: Exchanged MTU is propagate to ATT Server and GATT Client 919 920--- 921 922## Changes December 2017 923 924### Added 925- Introduced btstack_network.h network interface abstraction 926- btstack_network_posix implementation using Linux tun/tap interface 927- WICED: support for btstack_stdin (HAVE_STDIN) 928- GATT Server: Writes to GATT Client Characteristic Configuration are stored in TLV and restored on reconnect. The db.h file generated from db.gatt needs to be re-created. 929- TLV: global TLV instance available via btstack_tlv_get_instance() (src/btstack_tlv.h) 930- TLV: POSIX implementation that appends to a file on disk (platform/posix/btstack_tlv_posix.c 931- LE Device DB TLV: overwrite oldest entry if no free entries available 932- SM: allow to set fixed passkey in display role using sm_use_fixed_passkey_in_display_role 933- Example/hid_host_demo with HID parser and support for basic US keyboard layout 934- EM9304: custom HCI Transport implementation for EM9304 on top of btstack_em9304_spi.h platform abstraction only requires hal_em9304_spi.h to be implemented for new ports 935- Port for Apollo2 MCU with EM9304 (ports/apollo2-em9304) 936 937### Changed 938- panu_demo: uses btstack_network.h now 939- WICED: configure printf to replace Linefeed with CRLF 940- SBC: split btstack_sbc_bludroid.c into seperate encoder and decoder implementations 941 942### Fixed 943- RFCOMM: support connection requests during connection failure 944- L2CAP: support connection requests during connection failure 945- L2CAP: fix default remote MTU as 672 instead of 48 (Minimal MTU) 946- HCI: avoid double free during halting 947- SM: fixed reconnect using legacy pairing in slave role 948 949 950