Login to iOS application using fingerprint when one device is shared by multiple users

Question

We have a requirement where we need to login in to our application using fingerprints. We do understand that apple touch id can be used for authentication purpose and only returns success or failure in the response.

However, in our case one iPhone device will be shared by 5 to 8 users and we need to map an unique userId with each saved fingerprint to identify the user.

Is there any way to map a userid with the saved fingerprint (any unique number returned from an api like Fingerprint1, Fingerprint2 will do)?

Or Is there any alternative solution to login to our iOS application using biometric data?

We dont't want to add an extra fingerprint scanner device.

Answer 1

不，您无法知道生物识别中使用了多少和哪个手指，安全区域只会让您知道生物识别检查是否已通过。

Answer 2

No, You can't achieve this in iOS. According to Apple about biometric

Touch ID doesn't store any images of your fingerprint. It stores only a mathematical representation of your fingerprint. It isn't possible for someone to reverse engineer your actual fingerprint image from this mathematical representation. The chip in your device also includes an advanced security architecture called the Secure Enclave which was developed to protect passcode and fingerprint data. Fingerprint data is encrypted and protected with a key available only to the Secure Enclave. Fingerprint data is used only by the Secure Enclave to verify that your fingerprint matches the enrolled fingerprint data. The Secure Enclave is walled off from the rest of the chip and the rest of iOS. Therefore, iOS and other apps never access your fingerprint data, it's never stored on Apple servers, and it's never backed up to iCloud or anywhere else. Only Touch ID uses it, and it can't be used to match against other fingerprint databases.

Now come to main point.

Now days iPhone X series is more popular than other, and they don't support Touch ID, also you can store only one Face ID per device. not like the Touch ID (with multiple finger).

Or after certain wrong try of finger print the device will locked and you have provided Passcode, This is also one per device.