The Sources of Randomness in Smartphones with Symbian OS

This paper is focused on the analysis of randomness sources available in current mobile phones. We discuss specifics of the mobile devices, identify potential sources of randomness, and define types of possible attackers. An analysis of a camera and a microphone input noise as a source of randomness has been performed and amount of available entropy estimated. We then also statistically tested the obtained data using NIST test battery. Preliminary version of entropy extraction function was implemented using cryptographic hash function and its performance tested on several mobile phones.