  Physical Unclonable Functions (PUFs) are gaining attention in the
cryptography community because of the ability to efficiently harness the
intrinsic variability in the manufacturing process. However, this means that
they are noisy devices and require error correction mechanisms, e.g., by
employing Fuzzy Extractors (FEs). Recent works demonstrated that applying FEs
for error correction may enable new opportunities to break the PUFs if no
countermeasures are taken. In this paper, we address an attack model on FEs
hardware implementations and provide a solution for early identification of the
timing Side-Channel Attack (SCA) vulnerabilities which can be exploited by
physical fault injection. The significance of this work stems from the fact
that FEs are an essential building block in the implementations of PUF-enabled
devices. The information leaked through the timing side-channel during the
error correction process can reveal the FE input data and thereby can endanger
revealing secrets. Therefore, it is very important to identify the potential
leakages early in the process during RTL design. Experimental results based on
RTL analysis of several Bose-Chaudhuri-Hocquenghem (BCH) and Reed-Solomon
decoders for PUF-enabled devices with FEs demonstrate the feasibility of the
proposed methodology.
