Touch ID

As a Touch ID, the U.S. company Apple Inc. introduced in 2013 called a fingerprint scanner that is installed in -house Smartphone Apple iPhone 5s.

The fingerprint scanner was developed in order to unlock the device in a simple way, without using a password.

Data processing

In iPhone 5s up to five different fingerprints can be stored. However, it can therefore not be linked to multiple, device -related user accounts.

The fingerprints are not original, but permanently stored in the device only in the form of a checksum. This is obtained by means of a hash function and stored in the house A7 chip. Upon activation even further, user-related online services can be used.

The sensor has a resolution of 88x88 pixels, which corresponds to a pixel density of 500 ppi. Unlocking the scan of a fingerprint is transferred to the processor as compared to vectors and converted with the stored marks. The scanned stamp is deleted afterwards.

Security

The A7 processor of the iPhone 5s contains one responsible for the fingerprint sensor co-processor, which is operated with its own firmware. This Secure Enclave is assigned in the production of a unique ID that is neither Apple nor known to the manufacturer. During the boot process it is checked if the firmware of the co-processor is verified and signed by Apple. Potential vulnerabilities in iOS would therefore not allow manipulation of the fingerprint data. Data located in shared memory with iOS is encrypted with a unique ID and a counter and should be manipulated neither Apple nor for any attacker.

Criticism

In tests of the iPhone 5s the reliable functioning touch - ID sensor was praised.

On September 21, reported the Chaos Computer Club ( CCC), to have overcome the Touch ID security lock, even without a real finger. Here, a abfotografierter fingerprint with a laser printer in 1200dpi was printed on a transparency film and applied skin-colored latex milk or white wood glue. Heise Security chief editor Jürgen Schmidt holds Touch ID yet sensible, practicable and improve safety because " more than 50 percent of iPhone users who currently have no lock, finally set up a passcode " need to switch the function to to use.