GATT Server Auth: Expose PASSKEY_NOTIFY from BTManager -> BTDevice; App using AdapterStatusListener::devicePairingState() + SMPPairingState::PASSKEY_NOTIFY to display generated PassKey

3 files changed, 39 insertions, 0 deletions

diff --git a/src/direct_bt/BTAdapter.cpp b/src/direct_bt/BTAdapter.cpp
index 948a524d..3a8a1436 100644
--- a/src/direct_bt/BTAdapter.cpp
+++ b/src/direct_bt/BTAdapter.cpp
@@ -327,6 +327,7 @@ bool BTAdapter::enableListening(const bool enable) noexcept {
         ok = mgmt->addMgmtEventCallback(dev_id, MgmtEvent::Opcode::PIN_CODE_REQUEST, jau::bind_member(this, &BTAdapter::mgmtEvPinCodeRequestMgmt)) && ok;
         ok = mgmt->addMgmtEventCallback(dev_id, MgmtEvent::Opcode::USER_CONFIRM_REQUEST, jau::bind_member(this, &BTAdapter::mgmtEvUserConfirmRequestMgmt)) && ok;
         ok = mgmt->addMgmtEventCallback(dev_id, MgmtEvent::Opcode::USER_PASSKEY_REQUEST, jau::bind_member(this, &BTAdapter::mgmtEvUserPasskeyRequestMgmt)) && ok;
+        ok = mgmt->addMgmtEventCallback(dev_id, MgmtEvent::Opcode::PASSKEY_NOTIFY, jau::bind_member(this, &BTAdapter::mgmtEvPasskeyNotifyMgmt)) && ok;
         ok = mgmt->addMgmtEventCallback(dev_id, MgmtEvent::Opcode::AUTH_FAILED, jau::bind_member(this, &BTAdapter::mgmtEvAuthFailedMgmt)) && ok;
         ok = mgmt->addMgmtEventCallback(dev_id, MgmtEvent::Opcode::DEVICE_UNPAIRED, jau::bind_member(this, &BTAdapter::mgmtEvDeviceUnpairedMgmt)) && ok;
         ok = mgmt->addMgmtEventCallback(dev_id, MgmtEvent::Opcode::PAIR_DEVICE_COMPLETE, jau::bind_member(this, &BTAdapter::mgmtEvPairDeviceCompleteMgmt)) && ok;
@@ -2632,6 +2633,20 @@ void BTAdapter::mgmtEvUserPasskeyRequestMgmt(const MgmtEvent& e) noexcept {
     device->updatePairingState(device, e, HCIStatusCode::SUCCESS, SMPPairingState::PASSKEY_EXPECTED);
 }
 
+void BTAdapter::mgmtEvPasskeyNotifyMgmt(const MgmtEvent& e) noexcept {
+    const MgmtEvtPasskeyNotify &event = *static_cast<const MgmtEvtPasskeyNotify *>(&e);
+
+    BTDeviceRef device = findConnectedDevice(event.getAddress(), event.getAddressType());
+    if( nullptr == device ) {
+        WORDY_PRINT("BTAdapter:hci:SMP: dev_id %d: Device not tracked: address[%s, %s], %s",
+                dev_id, event.getAddress().toString().c_str(), to_string(event.getAddressType()).c_str(),
+                event.toString().c_str());
+        return;
+    }
+    DBG_PRINT("BTAdapter:mgmt:PasskeyNotify: %s", event.toString().c_str());
+    device->updatePairingState(device, e, HCIStatusCode::SUCCESS, SMPPairingState::PASSKEY_NOTIFY);
+}
+
 void BTAdapter::hciSMPMsgCallback(const BDAddressAndType & addressAndType,
                                    const SMPPDUMsg& msg, const HCIACLData::l2cap_frame& source) noexcept {
     BTDeviceRef device = findConnectedDevice(addressAndType.address, addressAndType.type);
diff --git a/src/direct_bt/BTDevice.cpp b/src/direct_bt/BTDevice.cpp
index 876463ed..caab6c58 100644
--- a/src/direct_bt/BTDevice.cpp
+++ b/src/direct_bt/BTDevice.cpp
@@ -768,6 +768,7 @@ std::string BTDevice::PairingData::toString(const uint16_t dev_id, const BDAddre
     res.append("  - IOCap "+to_string(ioCap_resp)+"\n");
     res.append("  - EncSz "+std::to_string(maxEncsz_resp)+"\n");
     res.append("  - Keys  "+to_string(keys_resp_has)+" / "+to_string(keys_resp_exp)+"\n");
+    res.append("    - PassKey "+toPassKeyString(passKey_resp)+"\n");
     res.append("    - "+ltk_resp.toString()+"\n");
     res.append("    - "+lk_resp.toString()+"\n");
     res.append("    - "+irk_resp.toString()+"\n");
@@ -836,6 +837,14 @@ bool BTDevice::updatePairingState(const std::shared_ptr<BTDevice>& sthis, const
                     dc.detach();
                 }
                 break;
+            case SMPPairingState::PASSKEY_NOTIFY:
+                if( MgmtEvent::Opcode::PASSKEY_NOTIFY == mgmtEvtOpcode ) {
+                    // we must be in slave/responder mode, i.e. peripheral/GATT-server providing auth passkey
+                    const MgmtEvtPasskeyNotify& event = *static_cast<const MgmtEvtPasskeyNotify *>(&evt);
+                    mode = PairingMode::PASSKEY_ENTRY_ini;
+                    pairing_data.passKey_resp = event.getPasskey();
+                }
+                break;
             case SMPPairingState::OOB_EXPECTED:
                 // 2
                 mode = PairingMode::OUT_OF_BAND;
@@ -1864,6 +1873,8 @@ void BTDevice::clearSMPStates(const bool connected) noexcept {
     pairing_data.use_sc = false;
     pairing_data.encryption_enabled = false;
 
+    pairing_data.passKey_resp = 0;
+
     pairing_data.authReqs_resp = SMPAuthReqs::NONE;
     pairing_data.ioCap_resp    = SMPIOCapability::NO_INPUT_NO_OUTPUT;
     pairing_data.oobFlag_resp  = SMPOOBDataFlag::OOB_AUTH_DATA_NOT_PRESENT;
@@ -2314,6 +2325,10 @@ exit:
     return res;
 }
 
+std::uint32_t BTDevice::getResponderSMPPassKey() const noexcept {
+    return pairing_data.passKey_resp;
+}
+
 HCIStatusCode BTDevice::unpair() noexcept {
     if constexpr ( USE_LINUX_BT_SECURITY ) {
         const BTManagerRef& mngr = adapter.getManager();
diff --git a/src/direct_bt/SMPTypes.cpp b/src/direct_bt/SMPTypes.cpp
index cfe68674..c842c8ec 100644
--- a/src/direct_bt/SMPTypes.cpp
+++ b/src/direct_bt/SMPTypes.cpp
@@ -53,6 +53,7 @@ static void append_bitstr(std::string& out, T mask, T bit, const std::string& bi
         X(FEATURE_EXCHANGE_COMPLETED) \
         X(PASSKEY_EXPECTED) \
         X(NUMERIC_COMPARE_EXPECTED) \
+        X(PASSKEY_NOTIFY) \
         X(OOB_EXPECTED) \
         X(KEY_DISTRIBUTION) \
         X(COMPLETED)
@@ -67,6 +68,14 @@ std::string direct_bt::to_string(const SMPPairingState state) noexcept {
     return "Unknown SMP PairingState";
 }
 
+std::string direct_bt::toPassKeyString(const std::uint32_t passKey) noexcept {
+    std::string pin;
+    pin.reserve(6+1); // including EOS for snprintf
+    pin.resize(6);
+    snprintf(&pin[0], pin.capacity(), "%06u", passKey%1000000u );
+    return pin;
+}
+
 #define IOCAP_ENUM(X) \
         X(DISPLAY_ONLY) \
         X(DISPLAY_YES_NO) \