Adapter Workflow

This section describes the enrollment workflow from the perspective of the adapter plugins.

In Windows 10, we have implemented a V4 engine interface that provides 2 new engine adapter functions, EngineAdapterCreateKey and EngineAdapterIdentifyFeatureSetSecure. These new functions allow support for secure biometrics using TPM 2.0. The following table shows the adapter-side enrollment workflow.

Client API	Adapter Methods
WinBioGetProperty(EXTENDED_ENGINE_INFO)	EngineAdapterQueryExtendedInfo
WinBioEnrollBegin	StorageAdapterQueryBySubject SensorAdapterClearContext EngineAdapterClearContext StorageAdapterClearContext EngineAdapterCreateEnrollment EngineAdapterSetEnrollmentParameters
WinBioEnrollCapture	SensorAdapterStartCapture SensorAdapterFinishCapture SensorAdapterPushDataToEngine[->EngineAdapterAcceptSampleData] If S_OK or WINBIO_I_MORE_DATA EngineAdapterUpdateEnrollment [Caller continues enrollment] Else if WINBIO_E_BAD_CAPTURE [Caller displays reject feedback, continues enrollment] Else if other ERROR EngineAdapterClearContext StorageAdapterClearContext [Bio service aborts enrollment]
WinBioGetProperty (EXTENDED_ENROLLMENT_STATUS)	EngineAdapterQueryExtendedEnrollmentStatus
WinBioEnrollCommit	EngineAdapterCheckForDuplicate If REMOVABLE DATABASE EngineAdapterGetEnrollmentHash EngineAdapterCommitEnrollment ElseEngineAdapterCommitEnrollment
WinBioEnrollDiscard	EngineAdapterDiscardEnrollment EngineAdapterClearContext StorageAdapterClearContext