PWINBIO_VERIFY_CALLBACK

Windows Biometric Framework から呼び出され、非同期の WinBioVerifyWithCallback 関数の結果を返します。クライアントアプリケーションはこの関数を実装する必要があります。

現在、Windows Biometric Framework は指紋リーダーのみをサポートしています。そのため、操作が失敗し、WINBIO_REJECT_DETAIL 定数で追加情報が返される場合、その値は次のいずれかになります:

• WINBIO_FP_TOO_HIGH
• WINBIO_FP_TOO_LOW
• WINBIO_FP_TOO_LEFT
• WINBIO_FP_TOO_RIGHT
• WINBIO_FP_TOO_FAST
• WINBIO_FP_TOO_SLOW
• WINBIO_FP_POOR_QUALITY
• WINBIO_FP_TOO_SKEWED
• WINBIO_FP_TOO_SHORT
• WINBIO_FP_MERGE_FAILURE

例

次の関数は WinBioVerifyWithCallback を呼び出し、生体認証サンプルが現在のユーザーのログオン ID と一致するかどうかを非同期に判定します。コールバックルーチン VerifyCallback と、ヘルパー関数 GetCurrentUserIdentity も併せて示します。Winbio.lib スタティックライブラリにリンクし、次のヘッダーファイルをインクルードしてください:

• Windows.h
• Stdio.h
• Conio.h
• Winbio.h

HRESULT VerifyWithCallback(BOOL bCancel, WINBIO_BIOMETRIC_SUBTYPE subFactor)
{
    // Declare variables.
    HRESULT hr = S_OK;
    WINBIO_SESSION_HANDLE sessionHandle = NULL;
    WINBIO_UNIT_ID unitId = 0;
    WINBIO_REJECT_DETAIL rejectDetail = 0;
    WINBIO_IDENTITY identity = {0};

    // Find the identity of the user.
    hr = GetCurrentUserIdentity( &identity );
    if (FAILED(hr))
    {
        wprintf_s(L"\n User identity not found. hr = 0x%x\n", hr);
        goto e_Exit;
    }

    // Connect to the system pool. 
    hr = WinBioOpenSession( 
            WINBIO_TYPE_FINGERPRINT,    // Service provider
            WINBIO_POOL_SYSTEM,         // Pool type
            WINBIO_FLAG_DEFAULT,        // Configuration and access
            NULL,                       // Array of biometric unit IDs
            0,                          // Count of biometric unit IDs
            NULL,                       // Database ID
            &sessionHandle              // [out] Session handle
            );
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioOpenSession failed. hr = 0x%x\n", hr);
        goto e_Exit;
    }

    // Verify a biometric sample asynchronously.
    wprintf_s(L"\n Calling WinBioVerifyWithCallback.\n");
    hr = WinBioVerifyWithCallback(
            sessionHandle,              // Open session handle
            &identity,                  // User SID or GUID
            subFactor,                  // Sample sub-factor
            VerifyCallback,             // Callback function
            NULL                        // Optional context
            );
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioVerifyWithCallback failed. hr = 0x%x\n", hr);
        goto e_Exit;
    }
    wprintf_s(L"\n Swipe the sensor ...\n");

    // Cancel the identification if the bCancel flag is set.
    if (bCancel)
    {
        wprintf_s(L"\n Starting CANCEL timer...\n");
        Sleep( 7000 );

        wprintf_s(L"\n Calling WinBioCancel\n");
        hr = WinBioCancel( sessionHandle );
        if (FAILED(hr))
        {
            wprintf_s(L"\n WinBioCancel failed. hr = 0x%x\n", hr);
            goto e_Exit;
        }
    }

    // Wait for the asynchronous identification process to complete 
    // or be canceled.
    hr = WinBioWait( sessionHandle );
    if (FAILED(hr))
    {
        wprintf_s(L"\n WinBioWait failed. hr = 0x%x\n", hr);
    }

e_Exit:
    if (sessionHandle != NULL)
    {
        WinBioCloseSession(sessionHandle);
        sessionHandle = NULL;
    }

    wprintf_s(L"\n Hit any key to continue...");
    _getch();

    return hr;
}

//------------------------------------------------------------------------
// The following function is the callback for WinBioVerifyWithCallback.
// The function filters the response from the biometric subsystem and 
// writes a result to the console window.
// 
VOID CALLBACK VerifyCallback(
  __in_opt PVOID VerifyCallbackContext,
  __in HRESULT OperationStatus,
  __in WINBIO_UNIT_ID UnitId,
  __in BOOLEAN Match,
  __in WINBIO_REJECT_DETAIL RejectDetail
  )
{
    UNREFERENCED_PARAMETER(VerifyCallbackContext);
    UNREFERENCED_PARAMETER(Match);

    wprintf_s(L"\n VerifyCallback executing");
    wprintf_s(L"\n Swipe processed for unit ID %d\n", UnitId);

    // The identity could not be verified.
    if (FAILED(OperationStatus))
    {
        wprintf_s(L"\n Verification failed for the following reason:");
        if (OperationStatus == WINBIO_E_NO_MATCH)
        {
            wprintf_s(L"\n No match.\n");
        }
        else if (OperationStatus == WINBIO_E_BAD_CAPTURE)
        {
            wprintf_s(L"\n Bad capture.\n ");
            wprintf_s(L"\n Bad capture; reason: %d\n", RejectDetail);
        }
        else
        {
            wprintf_s(L"VerifyCallback failed.");
            wprintf_s(L"OperationStatus = 0x%x\n", OperationStatus); 
        }
        goto e_Exit;
    }

    // The user identity was verified.
    wprintf_s(L"\n Fingerprint verified:\n");

e_Exit:
    return;
}

//------------------------------------------------------------------------
// The following function retrieves the identity of the current user.
// This is a helper function and is not part of the Windows Biometric
// Framework API.
//
HRESULT GetCurrentUserIdentity(__inout PWINBIO_IDENTITY Identity)
{
    // Declare variables.
    HRESULT hr = S_OK;
    HANDLE tokenHandle = NULL;
    DWORD bytesReturned = 0;
    struct{
        TOKEN_USER tokenUser;
        BYTE buffer[SECURITY_MAX_SID_SIZE];
    } tokenInfoBuffer;

    // Zero the input identity and specify the type.
    ZeroMemory( Identity, sizeof(WINBIO_IDENTITY));
    Identity->Type = WINBIO_ID_TYPE_NULL;

    // Open the access token associated with the
    // current process
    if (!OpenProcessToken(
            GetCurrentProcess(),            // Process handle
            TOKEN_READ,                     // Read access only
            &tokenHandle))                  // Access token handle
    {
        DWORD win32Status = GetLastError();
        wprintf_s(L"Cannot open token handle: %d\n", win32Status);
        hr = HRESULT_FROM_WIN32(win32Status);
        goto e_Exit;
    }

    // Zero the tokenInfoBuffer structure.
    ZeroMemory(&tokenInfoBuffer, sizeof(tokenInfoBuffer));

    // Retrieve information about the access token. In this case,
    // retrieve a SID.
    if (!GetTokenInformation(
            tokenHandle,                    // Access token handle
            TokenUser,                      // User for the token
            &tokenInfoBuffer.tokenUser,     // Buffer to fill
            sizeof(tokenInfoBuffer),        // Size of the buffer
            &bytesReturned))                // Size needed
    {
        DWORD win32Status = GetLastError();
        wprintf_s(L"Cannot query token information: %d\n", win32Status);
        hr = HRESULT_FROM_WIN32(win32Status);
        goto e_Exit;
    }

    // Copy the SID from the tokenInfoBuffer structure to the
    // WINBIO_IDENTITY structure. 
    CopySid(
        SECURITY_MAX_SID_SIZE,
        Identity->Value.AccountSid.Data,
        tokenInfoBuffer.tokenUser.User.Sid
        );

    // Specify the size of the SID and assign WINBIO_ID_TYPE_SID
    // to the type member of the WINBIO_IDENTITY structure.
    Identity->Value.AccountSid.Size = GetLengthSid(tokenInfoBuffer.tokenUser.User.Sid);
    Identity->Type = WINBIO_ID_TYPE_SID;

e_Exit:

    if (tokenHandle != NULL)
    {
        CloseHandle(tokenHandle);
    }

    return hr;
}