Add support for Bluetooth 5.0 Adapter (using HCI extended scanning and connecting if supported)

On Bluetooth 5.0 Adapter where HCI extended scanning and connecting is suppored,
the original HCI commands may fail via DISALLOWED.

Tested adapter: Intel AX200 Bluetooth 5.0 (Wi-Fi 6 802.11ax (2.4Gbps) + BT 5.0)

1 files changed, 85 insertions, 54 deletions

diff --git a/api/direct_bt/HCIHandler.hpp b/api/direct_bt/HCIHandler.hpp
index 780e1e63..9fb5716b 100644
--- a/api/direct_bt/HCIHandler.hpp
+++ b/api/direct_bt/HCIHandler.hpp
@@ -255,6 +255,16 @@ namespace direct_bt {
 
             std::recursive_mutex mtx_sendReply; // for sendWith*Reply, process*Command, ..; Recurses from many..
 
+            /**
+             * Cached bitfield of Local Supported Commands, 64 octets
+             * <pre>
+             * BT Core Spec v5.2: Vol 4, Part E, 6.27 (HCI) Supported Commands
+             * BT Core Spec v5.2: Vol 4, Part E, 7.4.2 Read Local Supported Commands command
+             * </pre>
+             */
+            uint8_t sup_commands[64];
+            jau::relaxed_atomic_bool sup_commands_set;
+
             jau::sc_atomic_bool allowClose;
             std::atomic<BTMode> btMode;
 
@@ -267,6 +277,9 @@ namespace direct_bt {
             /** Exclusive [le] connection command (status + pending completed) one at a time */
             std::mutex mtx_connect_cmd;
 
+            void zeroSupCommands() noexcept;
+            bool initSupCommands() noexcept;
+
             /**
              * Returns a newly added HCIConnectionRef tracker connection with given parameters, if not existing yet.
              * <p>
@@ -362,6 +375,17 @@ namespace direct_bt {
                 return true == allowClose.load() && comm.isOpen();
             }
 
+            /** Use extended scanning if HCI_LE_Set_Extended_Scan_Parameters and HCI_LE_Set_Extended_Scan_Enable is supported (Bluetooth 5.0). */
+            bool use_ext_scan() const noexcept{
+                return 0 != ( sup_commands[37] & ( 1 << 5 ) ) &&
+                       0 != ( sup_commands[37] & ( 1 << 6 ) );
+            }
+
+            /** Use extended connection if HCI_LE_Extended_Create_Connection is supported (Bluetooth 5.0). */
+            bool use_ext_conn() const noexcept{
+                return 0 != ( sup_commands[37] & ( 1 << 7 ) );
+            }
+
             ScanType getCurrentScanType() const noexcept { return currentScanType.load(); }
             void setCurrentScanType(const ScanType v) noexcept { currentScanType = v; }
 
@@ -398,18 +422,39 @@ namespace direct_bt {
             HCIStatusCode resetAdapter();
 
             /**
+             * HCI Reset Command
+             * <pre>
              * BT Core Spec v5.2: Vol 4, Part E HCI: 7.3.2 Reset command
+             * </pre>
              */
             HCIStatusCode reset() noexcept;
 
             HCIStatusCode getLocalVersion(HCILocalVersion &version) noexcept;
 
             /**
+             * Request and return LE_Features for the controller.
+             * <pre>
+             * BT Core Spec v5.2: Vol 6, Part B, 4.6 (LE LL) Feature Support
+             *
+             * BT Core Spec v5.2: Vol 4, Part E, 7.8.3 LE Read Local Supported Features command
+             * </pre>
+             * @param res reference for the resulting LE_Features
+             * @return HCIStatusCode
+             */
+            HCIStatusCode le_read_local_features(LE_Features& res) noexcept;
+
+            /**
              * Sets LE scanning parameters.
-             * <p>
+             * <pre>
+             * BT Core Spec v5.2: Vol 4 HCI, Part E HCI Functional: 7.8.64 LE Set Extended Scan Parameters command (Bluetooth 5.0)
+             *
+             * if available, otherwise using
+             *
              * BT Core Spec v5.2: Vol 4 HCI, Part E HCI Functional: 7.8.10 LE Set Scan Parameters command
+             *
+             *
              * BT Core Spec v5.2: Vol 6 LE, Part B Link Layer: 4.4.3 Scanning State
-             * </p>
+             * </pre>
              * <p>
              * Scan parameters control advertising (AD) Protocol Data Unit (PDU) delivery behavior.
              * </p>
@@ -430,9 +475,13 @@ namespace direct_bt {
 
             /**
              * Starts or stops LE scanning.
-             * <p>
+             * <pre>
+             * BT Core Spec v5.2: Vol 4 HCI, Part E HCI Functional: 7.8.65 LE Set Extended Scan Enable command (Bluetooth 5.0)
+             *
+             * if available, otherwise using
+             *
              * BT Core Spec v5.2: Vol 4, Part E HCI: 7.8.11 LE Set Scan Enable command
-             * </p>
+             * </pre>
              * @param enable true to enable discovery, otherwise false
              * @param filter_dup true to filter out duplicate AD PDUs (default), otherwise all will be reported.
              */
@@ -440,10 +489,12 @@ namespace direct_bt {
 
             /**
              * Start LE scanning, i.e. performs le_set_scan_param() and le_enable_scan() in one atomic operation.
-             * <p>
+             * <pre>
+             * BT Core Spec v5.2: Vol 4 HCI, Part E HCI Functional: 7.8.64 LE Set Extended Scan Parameters command (Bluetooth 5.0)
              * BT Core Spec v5.2: Vol 4 HCI, Part E HCI Functional: 7.8.10 LE Set Scan Parameters command
+             * BT Core Spec v5.2: Vol 4 HCI, Part E HCI Functional: 7.8.65 LE Set Extended Scan Enable command (Bluetooth 5.0)
              * BT Core Spec v5.2: Vol 4, Part E HCI: 7.8.11 LE Set Scan Enable command
-             * </p>
+             * </pre>
              * <p>
              * Scan parameters control advertising (AD) Protocol Data Unit (PDU) delivery behavior.
              * </p>
@@ -460,6 +511,7 @@ namespace direct_bt {
              * @param le_scan_interval in units of 0.625ms, default value 24 for 15ms; Value range [4 .. 0x4000] for [2.5ms .. 10.24s]
              * @param le_scan_window in units of 0.625ms, default value 24 for 15ms; Value range [4 .. 0x4000] for [2.5ms .. 10.24s]. Shall be <= le_scan_interval
              * @param filter_policy 0x00 accepts all PDUs (default), 0x01 only of whitelisted, ...
+             * @see le_read_local_features()
              */
             HCIStatusCode le_start_scan(const bool filter_dup=true,
                                         const bool le_scan_active=false,
@@ -469,9 +521,13 @@ namespace direct_bt {
 
             /**
              * Establish a connection to the given LE peer.
-             * <p>
+             * <pre>
+             * BT Core Spec v5.2: Vol 4, Part E HCI: 7.8.66 LE Extended Create Connection command (Bluetooth 5.0)
+             *
+             * if available, otherwise using
+             *
              * BT Core Spec v5.2: Vol 4, Part E HCI: 7.8.12 LE Create Connection command
-             * </p>
+             * </pre>
              * <p>
              * Set window to the same value as the interval, enables continuous scanning.
              * </p>
@@ -516,9 +572,9 @@ namespace direct_bt {
 
             /**
              * Establish a connection to the given BREDR (non LE).
-             * <p>
+             * <pre>
              * BT Core Spec v5.2: Vol 4, Part E HCI: 7.1.5 Create Connection command
-             * </p>
+             * </pre>
              * <p>
              * Implementation tries to mitigate HCIStatusCode::COMMAND_DISALLOWED failure due to any pending connection commands,
              * waiting actively up to HCIEnv::HCI_COMMAND_COMPLETE_REPLY_TIMEOUT, testing every HCIEnv::HCI_COMMAND_POLL_PERIOD if resolved.<br>
@@ -540,17 +596,32 @@ namespace direct_bt {
 
             /**
              * Disconnect an established connection.
-             * <p>
+             * <pre>
              * BT Core Spec v5.2: Vol 4, Part E HCI: 7.1.6 Disconnect command
-             * </p>
+             * </pre>
              */
             HCIStatusCode disconnect(const uint16_t conn_handle, const BDAddressAndType& addressAndType,
                                      const HCIStatusCode reason=HCIStatusCode::REMOTE_USER_TERMINATED_CONNECTION) noexcept;
 
             /**
-             * Clear all internal states, i.e. connection and disconnect lists.
+             * Request and return LE_PHYs bit for the given connection.
+             * <pre>
+             * BT Core Spec v5.2: Vol 4, Part E, 7.8.47 LE Read PHY command (we transfer the sequential value to this bitmask for unification)
+             * </pre>
+             * @param conn_handle
+             * @param addressAndType
+             * @param resRx reference for the resulting receiver LE_PHYs bit
+             * @param resTx reference for the resulting transmitter LE_PHYs bit
+             * @return HCIStatusCode
              */
-            void clearAllStates() noexcept;
+            HCIStatusCode le_read_phy(const uint16_t conn_handle, const BDAddressAndType& addressAndType,
+                                      LE_PHYs& resRx, LE_PHYs& resTx) noexcept;
+
+            /**
+             * Reset all internal states, i.e. connection and disconnect lists.
+             * @param powered_on indicates whether the adapter is powered on or not
+             */
+            void resetAllStates(const bool powered_on) noexcept;
 
 
             /** MgmtEventCallback handling  */
@@ -576,46 +647,6 @@ namespace direct_bt {
 
             /** Manually send a MgmtEvent to all of its listeners. */
             void sendMgmtEvent(const MgmtEvent& event) noexcept;
-
-            /**
-             * FIXME / TODO: Privacy Mode / Pairing / Bonding
-             *
-             * LE Secure Connections:
-             * <pre>
-             * BT Core Spec v5.2: Vol 1, Part A Architecture: 5.4 LE Security
-             * BT Core Spec v5.2: Vol 3, Part C GAP: 10.2 LE SECURITY MODES
-             * BT Core Spec v5.2: Vol 3, Part H SM: 2 Security Manager
-             * BT Core Spec v5.2: Vol 3, Part H SM: 2.3.5 Pairing: 2.3.5.6 LE Secure Connections pairing phase 2
-             * BT Core Spec v5.2: Vol 3, Part H SM: 2.3.5 Pairing: 2.3.5.6.3 LE Authentication stage 1 – Passkey Entry
-             * BT Core Spec v5.2: Vol 3, Part H SM: 3 Security Manager Protocol (SMP) fixed channel over L2CAP
-             *
-             *
-             * LE Legacy Pairing** similar to BREDR like: Secure Simple Pairing (SSP)
-             * LE Secure Connections functional equivalent to SSP, using 128 bit Long Term Key (LTK)
-             * </pre>
-             *
-             * <p>
-             * BT Core Spec v5.2: Vol 1, Part A Architecture: 5 Security architecture
-             * BT Core Spec v5.2: Vol 1, Part A Architecture: 5.4 LE Security
-             * BT Core Spec v5.2: Vol 1, Part A Architecture: 5.4.5 LE Privacy feature
-             * - device privacy mode (mixed mode, also accept other peer address)
-             * - network privacy mode (only private address - default!)
-             * -> add device to resolving list, implying being added to device white list!
-             *
-             * BT Core Spec v5.2: Vol 3, Part C GAP: 10.2 LE SECURITY MODES
-             *
-             * BT Core Spec v5.2: Vol 4, Part E HCI: 7.8.77 LE Set Privacy Mode command
-             * BT Core Spec v5.2: Vol 6 LE Adapter, Part B Link Layer Spec: 4.7 Resolving List
-             * </p>
-             * FIXME: TODO
-             *
-             * @return
-             * HCIStatusCode le_set_privacy_mode();
-             *
-             * Fills buffer with random bytes, usually 16 bytes for 128 bit key.
-             * FIXME: TODO
-             * static bool generateIRK(uint8_t *buffer, int size);
-             */
     };
 
 } // namespace direct_bt