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### Fixed 12### Added 13### Changed 14 15## Changes November 2020 16 17### Fixed 18- L2CAP: trigger pairing for outgoing LE Data Channels if security level insufficient 19- SM: fix update of sc flag for re-encrypted connection in peripheral role 20 21### Added 22 23### Changed 24AVRCP Controller: allow to send multiple absolute volume commands without waiting for response. 25 26## Changes October 2020 27 28### Fixed 29- AVRCP/AVCTP: report AVRCP 1.6 and AVCTP 1.4 in SDP record 30- AVDTP Initiator: avoid use of remote seid for stream endpoint lookup, fixes issue with two connected devices 31- AVDTP Source: buffer for SBC media codec information got discarded, leading to invalid Set Configuration command in second connection 32- SM: only trigger Cross-Transport Key Derivation (CTKD) when bonding is enabled 33- SM: set LinkKey flag to request CTKD if enabled 34- SM: store CTKD key with Public Identity Address 35- SM: only allow CTKD to overwrite existing link key if derived key has same or higher authentication 36- SM: sending Security Request by Responder starts SMP Timeout 37- HFP HF: fix response to AG Codec Selection while waiting for OK of parallel command 38- HCI: fix reject of LE remote connection param request via HCI 39 40### Added 41- GAP: add `gap_get_link_key_for_bd_addr` 42- GAP: add `gap_bonded` to check if bonding information is available for active connection 43- SM: support h7 for CTKD 44 45### Changed 46- SM: Cross-Transport Key Derivation requires `ENABLE_CROSS_TRANSPORT_KEY_DERIVATION` now 47 48## Changes September 2020 49 50### Fixed 51- HFP: fix parsing of ranges e.g. in +CIND responses 52- AVDTP, AVRCP: fix bugs due to transaction id overrun 53- A2DP Source: fix issues with stream configuration by sink 54- hci_dump: fix tv_us calculation for non-posix / embedded systems with binary output 55 56### Added 57- `btstack_ring_buffer`: add `btstack_ring_buffer_reset` to reset it to initial state/empty 58- GAP: Support for address resolution of resolvable private addresses by Controller with `ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION` 59 60### Changed 61- AVDTP, AVRCP, HSP: schedule SDP query, avoids avoids 'command disallowed' if SDP client is busy 62- HSP, HFP: allow to configure usable SCO packet types 63- cc256x: update CC256xC init script to v1.4 64- A2DP Source: use Get All Capabilities if supported by remote get Delay Reporting capability 65 66## Changes August 2020 67 68### Fixed 69- ESP32: fix authentication for incoming Secure Connections 70- AVDTP: Fix forwarding of Delay reports 71- STM32-F4Discovery: fix pan_lwip_http_server by increasing HCI_ACL_PAYLOAD_SIZE 72- tool/create_packet_log: basic support for 16-bit Unicode log files from Windows 73 74### Added 75- `btstack_run_loop_base`: added `btstack_run_loop_base_dump_timer` 76- GAP: request role change for classic connection via `gap_request_role` 77- GAP: LE Whitelist API with `gap_le_whitelist_x` with x = add, remove, clear and new `gap_connect_with_whitelist` 78- SDP Client: add sdp_client_register_query_callback() allows to register query request instead of polling sdp_client_ready() 79- BNEP lwIP: add `bnep_lwip_connect` to establish BNEP connection and manage lwIP network interface 80- New `btstack_linked_queue` utility, a linked list-based queue with first-in-first-out semantics and constant time enqueue/dequeue operations 81- btstack_tlv_posix: add `btstack_tlv_posix_deinit` 82- New `btpclient` for use with [auto-pts project](https://github.com/intel/auto-pts) 83 84### Changed 85- GAP: treat AES-CCM encrypted connection as mutually authenticated (BIAS) 86- GAP: 'gap_auto_connect_x' API deprecated. Please direclty manage LE Whitelist with `gap_le_whitelist_*` functions and call `gap_connect_with_whitelist` instead 87- example/hid_host_demo: try to become master for incoming connections 88- btstack_run_loop: use btstack_assert instead of local while(true) 89- att_db_util: allow to reset att_db via `att_db_util_init` 90 91## Changes July 2020 92 93### Fixed 94- AVDTP: fix invalid response for Get Capabilities request if Delay Reporting was supported 95- AVDTP: handle concurrent signaling establishment with reject and retry 96 97### Added 98- example/hid_host_demo: support reconnect from HID device 99- Crypto: support software AES128 for AES-CCM operations 100- AVRCP: introduced AVRCP_FEATURE_MASK_* as alternative to avrcp_controller_supported_feature_t and avrcp_target_supported_feature_t enums 101- btstack_audio: add set_volume() to sink and set_gain() to source interfaces, minimal volume control for portaudio playback 102- 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 103- GAP: Provide gap_get_role to query master/slave role for HCI connection handle 104- GAP: Provide gap_pin_code_response_binary to use binary data as PIN, e.g. for pairing with Nintendo Wii Remote 105 106### Changed 107- GAP: set minimum required encryption key size for Classic connections back from 16 to 7, matching the Core spec 108 109 110## Changes June 2020 111 112### Fixed 113- HFP: Fix parsing of empty fields, e.g. phone number in +CLCC and other AT commands 114- SM: Fix validation of confirm value for secure connection Passkey entry 115- AVRCP: handle concurrent signaling establishment with reject and retry 116 117### Added 118- GAP: Detect Secure Connection -> Legacy Connection Downgrade Attack by remote features and actual encryption type (BIAS) 119- GAP: Mutual authentication: request authentication after Classic connection got encrypted (BIAS) 120- Windows port for Dialog DA14585 connected via serial port 121 122## Changes 123- CVSD PLC: treat zero frames as good and allow to mark data as bad, e.g. if reported by Controller as erroneous 124 125## Changes May 2020 126 127### Fixed 128- hfp_hf, hsp_hs: use eSCO params in accept sco connection only for incoming eSCO connections 129- pbap_client: fix PBAP UUID len on connect message 130- SM: fix secure connection pairing as peripheral when local user confirmation happens after remote one 131- A2DP Source: only connect to remote sink stream endpoints 132- btstack_hal_flash_memory: fix write of 0xff bytes to simulated flash 133- hsp_hs: fix disconnect if audio not connected 134- hsp_ag: fix accept incoming connection 135 136### Added 137- example/le_mitm: MITM implementation that forwards ATT PDUs and allows for pairing 138- GAP: gap_set_security_level sets required security level for incoming and outgoing connections 139- cc256x: allow to specify power vector for each modulation type 140- FreeRTOS: btstack_run_loop_freertos_trigger_exit allows to request run loop exit 141- SM: support LE Secure Connections Only mode with sm_set_secure_connections_only_mode 142- GAP: enable BR/EDR Secure Connections if supported, add gap_secure_connections_enable 143 144### Changed 145- L2CAP ERTM: send extended features request only once per HCI connection 146 147 148## Changes April 2020 149 150### Fixed 151- hog_mouse_demo/hog_keyboard_demo: handle set protocol mode = boot protocol mode 152- HCI: only update BD_ADDR placeholder in shortened and complete name in EIR data, limit device name to 240/248 bytes 153 154### Added 155- GAP: gap_set_allow_role_switch allows to prevent role switch in outgoing classic ACL connections 156- example: hog_boot_host_demo implements an HID-over-GATT Boot Host that supports keyboard and mouse 157- HCI: add ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS that forces fragmentation of ACL-LE packets to fit into over-the-air packet 158 159### Changed 160- Broadcom/Cypress: wait 300 ms after PatchRAM update in hci.c to assert Controller is ready 161- esp32: provide esp-idf/component/btstack/btstack_port_esp32.c and only minimal app_main in template/main/main.c 162- att_db: skip att_read_callback for ATT Read Blob Request if offset == value_len 163 164 165## Changes March 2020 166 167### Fixed 168- GAP: fixed gap_set_scan_parameters() if issued right before gap_start_scan() 169- HCI: only send HCI Read Local Encryption Key Size if supported by Controller 170 171### Added 172- GATT Client: allow to register for any notification/indication and/or any connection 173- HCI: added hci_read_inquiry_scan_activity and hci_write_inquiry_scan_activity commands 174- chipset: assert hci packet buffers are suitable for firmware upload or patches (atwilc3000,bcm,cc256x,intel) 175- btstack_util: added btstack_replace_bd_addr_placeholder 176 177### Changed 178- AVRCP Target: volume in avrcp_target_volume_changed is reported as current value in interim response to register for volume change notifications 179- SDP Client: query attributes 0x0000..0xffff instead of 0x0001..0xffff to match other stacks / improve compatibility with bad sdp server implementations 180 181 182## Changes Februar 2020 183 184### Fixed 185- AVRCP Target: fix reporting of PLAYBACK_STATUS_CHANGED 186- HCI: handle reconnect request for Classic and LE connections triggered by packet handler for Disconnection Complete Event 187 188### Changed 189- hid_host_mode: allow sniff mode 190 191### Added 192- 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 193 194 195## Changes January 2020 196 197### Fixed 198- L2CAP ERTM: avoid read-after-free on decline of incoming connection 199- GATT Client: set uuid16 to zero when deserializing uuid128 services, characteristics, and descriptors 200- att_db_util: fix realloc of att db buffer for large attributes 201- btstack_tlv_posix: only keep last value in memory, fix delete operation 202- l2cap_signaling: use packet boundary flags 0x00 for LE signaling packets (ignoring hci_non_flushable_packet_boundary_flag_supported()) 203 204### Added 205- att_db_util: provide GATT Database Hash via att_db_util_hash_calc 206- GATT Compiler: provide GATT Database Hash via GATT_DATABASE_HASH Characteristic 207- ATT Server: validate request pdu length 208 209### Changed 210- Crypto: update AES-CMAC implementation to access all message bytes sequentially 211 212 213## Changes December 2019 214 215### Fixed 216- example/pan_lwip_http_server: use Network Access Point, CoD 217- sm: emit pairing complete in master role when no keys are distributed / bonding disabled 218 219### Added 220 221### Changed 222- Updated CC256x initscript: CC256xC v1.3 223- ESP32: add CMake project files 224 225 226## Changes November 2019 227 228### Fixed 229- AVDTP Source: return correct `avdtp_cid` and `local_seid` in `AVDTP_SUBEVENT_STREAMING_CAN_SEND_MEDIA_PACKET_NOW` 230- L2CAP: send LE Data Channel SDUs round robin with other data 231- L2CAP ERTM: send ERTM I-frames round robin with other data 232 233### Added 234- ATT Server: return error if request to send now for Notification or Indication already registered 235- Linked List: return if item was added for `btstack_linked_list_add[_tail]` 236- btstack_run_loop_remove: return bool true if timer/data source was removed 237- segger-rtt: allow to configure with `SEGGER_RTT_PACKETLOG_*` directives, update to v6.54 238- GAP: support setting Link Supervision Timetout for outgoing Classic connections using `gap_set_link_supervision_timeout` 239- lwip: add download test files to http server demo 240 241### Changed 242- Linked List: return bool true if item was removed 243 244 245## Changes October 2019 246 247### Fixed 248 249### Added 250- `btstack_bool.h`: provide boolean type 'bool' via `<stdbool.h>` or as backport 251- provide `btstack_assert(condition)` 252- H4 Transport: avoid calling `hci_transport_h4_trigger_next_read` when transport is closed 253 254### Changed 255- libusb and posix ports: store bonding information in TLV 256 257 258## Changes September 2019 259 260### Fixed 261- L2CAP ERTM: assert that packet can be stored in fragment buffers in ertm 262- L2CAP ERTM: reject incoming connection if ERTM is configured as mandatory but not supported by remote 263- GATT Client: allow Write Without Response independent of other requests 264 265### Added 266- GAP: allow to reject GAP classic connection via gap_register_classic_connection_filter 267- GAP: support reading RSSI for Classic+LE using gap_read_rssi. Emits `GAP_EVENT_RSSI_MEASUREMENT` 268 269### Changed 270- Bluetooth and BTstack Error Codes and Events: collect status codes in bluetooth.h and events in btstack_defines.h 271- bluetooth.h: extract internal defintitions to respective protocol layers 272- Updated CC256x initscripts (CC256xB v1.8, CC256xC v1.2, CC256xC v1.2) 273 274 275## Changes August 2019 276 277### Fixed 278- POSIX, WICED, Windows, FreeRTOS run loops: handle time_ms overrun after 49 days 279- RFCOMM: accept incoming L2CAP connection in Basic mode if ERTM is enabled but not requested for this connection 280- RFCOMM: limit RFCOMM MTU by local L2CAP MTU for outgoing connections (only revelvant for ERTM) 281- L2CAP ERTM: stop timers on disconnect 282- L2CAP ERTM: fix sending of segmented SDUs 283- L2CAP ERTM: handle unsupported Information Response 284- SM: generate local nonce for confirm value in JW+NC+PK in Secure Connections Responder role 285 286### Added 287- `btstack_run_loop_base`: portable implementation of timer and data source management as base for platform specific implementations 288 289## Changed 290- FreeRTOS: use xQueueCreateStatic (static variant of xQueueCreate) if available for static memory-only setups 291- L2CAP ERTM: handle invalid Information Response (assume no extended features supported) 292- POSIX: use monotonic clock as timebase if available 293- HCI Transport H4/H5/EM9304 SPI: ignore block read/sent from UART driver when closed 294- HCI: Read Encryption Key Size after encryption was enabled 295- Errata 11838: 296 - GAP: gap_set_required_encryption_key_size allows to set the required key size, default = 16 (max) 297 - GAP: validate encryption key size to emit GAP Security Levels 298 299## Changes July 2019 300 301### Fixed 302- SM: Fixed regression introduced in f3582630 303- L2CAP: avoid reading l2cap signaling command len out of bounds 304- HCI Transport H4/H5/EM9304 SPI: fix payload size checks (also for 8/16-bit platforms) 305 306### Changed 307- SM: Start encryption upon receiving slave securiy request if bonded 308- hci: use 2 as HCI_INCOMING_PRE_BUFFER_SIZE in LE-only configuration for GATT Client 309 310--- 311 312## Changes June 2019 313 314### Changed 315- FreeRTOS: use freertos/.. prefix to include FreeRTOS headers if HAVE_FREERTOS_INCLUDE_PREFIX is defined 316- BNEP: add Connection Handle to BNEP_EVENT_CHANNEL_OPENED 317- Examples: renamed le_counter to gatt_counter and le_streamer to le_streamer_server to indicate suppport for GATT over BR/EDR 318 319### Fixed 320- BNEP: Bluetooth address is stored in little-endian format for all BNEP_EVENT_* 321- libusb: avoid use-after-free for SCO packets on disconnect 322 323### Added 324- example: pan_lwip_http_server using lwIP as network stack to implement PAN NAP service 325- platform/lwip/bnep_lwip.c: BNEP lwIP adapter that forwards packets between BNEP service and lwIP 326- ENABLE_GATT_OVER_CLASSIC enables support for GATT over BR/EDR in att_server 327 328--- 329 330## Changes May 2019 331 332### Changed 333- ESP32: Configure SCO over HCI after power up 334- btstack_tlv_flash_bank: support targets where a value cannot be overwritten with zero. When ENABLE_TLV_FLASH_EXPLICIT_DELETE_FIELD 335 is defined, an explicit delete field is used to indicate an invalid entry. 336 337### Fixed 338- SM: Avoid potential use-after-free on immediate disconnect (lookup connection via con handle instead of storing pointer) 339 340### Added 341- gatt_client: emit query complete event for signed write operation 342- hci_transport_h4: add workaround for flow control bug in CYW2070x, enable with ENABLE_CYPRESS_BAUDRATE_CHANGE_FLOWCONTROL_BUG_WORKAROUND 343 344--- 345 346## Changes April 2019 347 348### Changed 349- ESP32: use micro-ecc from 3rd-party as esp-idf removed it in their 3.3 release 350 351### Fixed 352- hci: pad LE Scan response with zeroes 353- SM: store local CSRK 354- ATT DB: call write callback for validated signed writes 355- ATT Server: abort signed write validation on incoming new request 356- Bluetooth SIG web scraping tools updated 357- libusb: compiles for FreeBSD 358 359### Added 360 361--- 362 363## Changes March 2019 364 365### Changed 366- use Makefile for stm32-f4discovery-cc256x port 367- le_device_db: add secure_connection argument to le_device_db_encryption_set and le_device_db_encryption_get 368 369### Fixed 370- SM: Use provided authentication requirements in slave security request 371 372### Added 373- port/stm32-f4discovery-cc256x: add support for built-in MEMS microphone 374- SM: Track if connection encryption is based on LE Secure Connection pairing 375- ATT DB: Validate if connection encrypted is based on SC if requested 376- att_db_util: support ATT_SECURITY_AUTHENTICATED_SC permission flag 377- GATT Compiler: support READ_AUTHENTICATED and WRITE_AUTHENTICATED permsission flags 378- ESP32: erase nvs flash is newer nvs version found 379- libusb: add support for nRF52840-PCA10056 running Zephyr hci_usb example 380- port/stm32-l073rz-nucleo-em9304 for Nucleo L073RZ with EM9304 DVK, replaces port/stm32-l053r8-nucleo-em9304 381 382## Changes February 2019 383 384### Changed 385- example/a2dp_sink_demo: use linear resampling to fix sample rate drift 386- btstack_audio: split interface into sink and source 387 388### Fixed 389- Crypto: fix lockup when stack is shutdown while waiting for result of HCI Command, e.g. LE Read Local P256 Public Key 390- SM: Avoid SM_EVENT_PAIRING_COMPLETE with ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION after successful pairing in responder role 391 392### Added 393- example/a2dp_sink_demo: add target role, support volume control on both devices 394- example/audio_duplex: playback audio audio source on audio sink (test audio path) 395- btstack_audio_embedded: implement audio source path 396 397--- 398 399## Changes January 2019 400 401### Changed 402- L2CAP: provide channel mode (basic/ertm) and fcs option in L2CAP_EVENT_CHANNEL_OPENED 403- RFCOMM: support L2CAP ERTM. Callbacks passed to rfcomm_enable_l2cap_ertm() are used to manage ERTM buffers 404 405### Added 406- L2CAP: emit L2CAP_EVENT_ERTM_BUFFER_RELEASED if ERTM buffer not needed/used anymore 407- L2CAP: add fcs_option to ERTM config l2cap_ertm_config_t 408- HCI: validate advertisement data length field when generating GAP_EVENT_ADVERTISING_REPORT 409- ad_parser: validate data element length fields in ad_iterator_has_more 410- Raspberry Pi 3 A+/B+ port in port/raspi, starts without power cycle 411 412### Fixed 413- HCI: release outgoing buffer on disconnect if waiting to send another ACL fragment 414- POSIX: use correct baudrate enums for baud rates higher than 921600 (Linux) 415- Crypto: directly process queued crypto operation on HCI result 416 417--- 418 419## Changes December 2018 420 421### Added 422- SM: generate and store ER / IR keys in TLV, unless manually set by application 423- hci_dump: support PacketLogger or BlueZ format output via SEGGER RTT Channel 1 Up 424 425### Fixed 426- SM: fix internal buffer overrun during random address generation 427 428## Changes November 2018 429 430### Added 431- GAP: gap_le_connection_interval provides connection interval for conn handle 432- Nordic SPP Service Server: GATT service that emulates a serial port over BLE based on Nordic Semiconductor documentation. 433- uBlox SPP Service Server: GATT service that emulates a serial port over BLE based on uBlox documentation. 434- SM: ENABLE_LE_CENTRAL_AUTO_ENCRYPTION triggers automatic encryption on connect to bonded devices 435- SM: generate and store ER / IR keys in TLV, unless manually set by application 436 437### Fixed 438- SM: prevent random address updates if gap_random_address_set was used 439- SM: fix internal buffer overrun that can cause storing of bonding information to fail 440- SM: ignore Slave Security Request after sending own Pairing Request 441- L2CAP: fix use after free on disconnect if ERTM is enabled 442- HFP: Handle multiple commands/responses in single RFCOMM packet 443- Memory Pools: clear all buffers before use 444 445--- 446 447## Changes October 2018 448 449### Added 450- SDP Server: queue incoming connections when already connected instead of rejecting them 451- 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. 452- HIDS Device: GATT service that exposes HID reports intended for HID Devices, like keyboard and mouse. 453 454### Fixed 455- HCI: fix bug in gap_inquiry_stop that triggered additional GAP_EVENT_INQUIRY_COMPLETE instead of stopping the inquiry 456- L2CAP: fix issue with outgoing connection before read remote supported complete when other channels exist 457- L2CAP ERTM: allow SDU of szie MPS in first packet that contains L2CAP SDU Length 458- L2CAP ERTM: fix memory corruption triggered if local_mtu > mps 459- L2CAP ERTM: fix outgoing fragment management 460- HFP: decline incoming RFCOMM connection after outgoing connection was started 461- AVRCP: fix crash on disconnect of connection established by remote 462 463--- 464 465## Changes September 2018 466 467### Fixed 468- HCI: Error creating outgoing connection (e.g. Connection Limit Exceeded) now handled 469- L2CAP: Error creating outgoing connection (e.g. Connection Limit Exceeded) now handled 470- L2CAP: Evaluate 'can send now' on HCI Disconnect as ACL buffers in Bluetooth Controller have been used for the closed connection are freed implicitly 471- L2CAP: Check can send now before sending extended information requeste needed for ERTM mode 472- L2CAP: Use valid signaling identifier for L2CAP Connection Parameter Update Request 473- 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 474- RFCOMM: Avoid use-after-free on channel finalize 475- GATT Client: stop timer on disconnect - fixes use after free / crash 476 477### Added 478- A2DP Source: Support stream reconfiguration (a2dp_source_reconfigure_stream_sampling_frequency) 479- 3rd-party: yxml is used for PBAP vCard list parsing 480- cc256xC: new v1.1 init scripts 481 482--- 483 484## Changes August 2018 485 486### Added 487- PBAP: added pbap_get_phonebook_size() to get phonebook entry count 488 489### Fixed 490- GATT Server: Allow enable Notifications/Indication with Write Command. Fixes issue with some Android devices. 491- SM: fix pairing for Secure Connections with Bonding if remote sends additional keys 492- SM: drop LTK flag from Pairing Response for Secure Connections 493- L2CAP: fix emitted L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_REQUEST 494 495## Changes June 2018 496 497### Added 498- btstack_audio.h: application level API for audio playback and recording 499- embedded/hal_audio.h: low-level API for audio playback and recording 500- HID Device: hid_device_connect(..) function 501- ESP32: implement hal_audio 502- DA14585: support for Dialog Semiconductor DA14585 LE-only controller 503- Raspberry Pi 3 + Raspberry Pi Zero W port in port/raspi 504 505### Changed 506- Errata 10734: 507 - SM: Generate new EC Public Keypair after each pairing 508 - SM: Abort failure with DHKEY_CHECK_FAILED if received public key is invalid (instead of unspecified error) 509- btstack.h: only include classic headers if ENABLE_CLASSIC is defined 510- windows: ignore virtual Bluetooth adapter provided by VMware 511- Replaced HCI_PACKET_BUFFER_SIZE with HCI_INCOMING_PACKET_BUFFER_SIZE and HCI_OUTGOING_PACKET_BUFFER_SIZE 512 513--- 514 515## Changes June 2018 516 517### Fixed 518- HFP: Fix Wide Band Speech bit in SDP record for both HF/AG. Missing bit prevents macOS from using mSBC 519- ATT Server: send ATT_EVENT_HANDLE_VALUE_INDICATION_COMPLETE with status ATT_HANDLE_VALUE_INDICATION_DISCONNECT on disconnect 520- AVRCP Controller: fix parsing of now playing info 521 522### Changed 523- ATT Server: ATT_HANDLE_VALUE_INDICATION_DISCONNECT is delivered to service handler if registered 524 525### Added 526- ATT Server: packet handler field added to att_service_handler_t to receive: connect/disconnect, atu exchange, indication complete 527 528--- 529 530## Changes May 2018 531 532### Added 533- GAP: re-encrypt outgoing connection if bonded 534- ATT Server: wait until re-encryption is complete 535- GATT Client: wait until re-encryption is complete 536- ATT Server: added att_server_request_to_send_notification and att_server_request_to_send_indication 537- GATT Client: if ENABLE_GATT_CLIENT_PAIRING, GATT Client starts pairing and retry operation on security error 538 539### Changed 540- ATT Server: att_server_register_can_send_now_callback is deprecated, use att_server_request_to_send_notification/indication instead 541 542### Fixed 543- SM: Fix LE Secure Connection pairing in Central role 544- le_device_db_tlv: fix seq nr management 545- SM: improve le_device_db lookup and storing of IRK 546- GATT Server: fix lookup for Client Characteristic Configuration in services with multiple Characteristics 547- RFCOMM: emit channel closed on HCI/L2CAP disconnect after sending DISC while expecting UA 548 549--- 550 551## Changes April 2018 552 553### Added 554- Crypto: btstack_crypo.h provides cryptographic functions for random data generation, AES128, EEC, CBC-MAC (Mesh) 555- SM: support pairing using Out-of-Band (OOB) data with LE Secure Connections 556- Embedded: support btstack_stdin via SEGGER RTT 557 558### Changed 559- att_db_util: added security requirement arguments to characteristic creators 560- SM: use btstack_crypto for cryptographpic functions 561- GAP: security level for Classic protocols (asides SDP) raised to 2 (encryption) 562 563### Fixed 564- HFP: fix answer call command 565- HCI: fix buffer overrun in gap_inquiry_explode 566- SDP: free service record item on sdp_unregister_service 567 568## Changes March 2018 569 570### Added 571- GAP: allow to limit number of connections in LE Peripheral role with gap_set_max_number_peripheral_connections 572- ATT Server: support for delayed ATT read response, see example/att_delayed_read_response.c 573- ATT Server: allow to specify security requirements seperately for read/writes. .h files need to be regenerated 574 575### Fixed 576- RFCOMM: fix infinite loop on L2CAP connection error (regression from 4c3eeed1) 577- HSP HS: accept incomming SCO connection 578- SM: fix iteration over LE Device DB entries for bonding and address resolving 579- SM: store pairing information only if both devices have requested bonding 580 581--- 582 583## Changes February 2018 584 585### Added 586- GATT Client: gatt_client_request_can_write_without_response_event() causes GATT_EVENT_CAN_WRITE_WITHOUT_RESPONSE 587- SM: new event SM_EVENT_PAIRING_COMPLETE 588- GAP: support iteration over stored Classic link keys: gap_link_key_iterator_init, gap_link_key_iterator_get_next, gap_link_key_iterator_done 589- GAP: add gap_delete_all_link_keys 590 591### Changed 592- GATT Client: round robin for multiple connections 593- ATT Dispatch: round robin for ATT Server & GATT Client 594- L2CAP: round robin for all L2CAP channels (fixed and dynamic) 595- btstack_link_key_db: addition functions for link key iteration 596- GAP: LE scanning enabled not reset on HCI Reset -> can be enabled before HCI Power Up 597- CSR: set all keys in psram instead of default 598 599### Fixed 600- tc3556x: fix startup after baud rate change 601 602--- 603 604## Changes January 2018 605 606### Added 607- Port for Windows with Zephyr HCI Firmware connected via serial port 608- em9304: upload patch containers during HCI bootup 609- Makefile for STM32-F4Discovery port 610- support for console out via SEGGER RTT 611- LE Data Channels example in BTstack and [iOS example on GitHub](https://github.com/bluekitchen/CBL2CAPChannel-Demo) 612- LE Streamer Client can send as fast as possbile as well 613- L2CAP: option to limit ATT MTU via l2cap_set_max_le_mtu 614 615### Changed 616- HCI: allow to set hci_set_master_slave_policy (0: try to become master, 1: accept slave) 617- GAP: gap_set_connection_parameters includes scan interval and window params 618- GATT Client: GATT_EVENT_MTU indicates max MTU 619- ATT DB Util: attribute handle is returned for new Services and Characteristics 620 621### Fixed 622- Windows: retry serial port operations if not all bytes have been read/written 623- HFP: avoid buffer overflows setting up messages 624- SBC Decoder: improved error handling for invalid SBC audio data 625- GAP: fix Connection Parameter Response in Central role 626- ATT DB Util: update pointer to database in case of realloc 627- GATT Client: set UUID16 field if 16-bit UUID is stored as UUID128 628- GAP: release HCI Connnection after gap_le_conne 629- ATT: Exchanged MTU is propagate to ATT Server and GATT Client 630 631--- 632 633## Changes December 2017 634 635### Added 636- Introduced btstack_network.h network interface abstraction 637- btstack_network_posix implementation using Linux tun/tap interface 638- WICED: support for btstack_stdin (HAVE_STDIN) 639- 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. 640- TLV: global TLV instance available via btstack_tlv_get_instance() (src/btstack_tlv.h) 641- TLV: POSIX implementation that appends to a file on disk (platform/posix/btstack_tlv_posix.c 642- LE Device DB TLV: overwrite oldest entry if no free entries available 643- SM: allow to set fixed passkey in display role using sm_use_fixed_passkey_in_display_role 644- Example/hid_host_demo with HID parser and support for basic US keyboard layout 645- 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 646- Port for Apollo2 MCU with EM9304 (ports/apollo2-em9304) 647 648### Changed 649- panu_demo: uses btstack_network.h now 650- WICED: configure printf to replace Linefeed with CRLF 651- SBC: split btstack_sbc_bludroid.c into seperate encoder and decoder implementations 652 653### Fixed 654- RFCOMM: support connection requests during connection failure 655- L2CAP: support connection requests during connection failure 656- L2CAP: fix default remote MTU as 672 instead of 48 (Minimal MTU) 657- HCI: avoid double free during halting 658- SM: fixed reconnect using legacy pairing in slave role 659 660 661