Signal Processing for Cryptography and Security Applications

Embedded devices need both an efficient and a secure implementation of cryptographic primitives. In this chapter we show how common signal processing techniques are used in order to achieve both objectives. Regarding efficiency, we first give an example of accelerating hash function primitives using the retiming transformation, a well known technique to improve signal processing applications. Second, we outline the use of some special features of DSP processors and techniques earlier developed for efficient implementations of public-key algorithms. Regarding the secure implementations we outline the concept of side channel attacks and show how a multitude of techniques for preprocessing the data are used in such scenarios. Finally, we talk about fuzzy secrets and point out the use of DSP techniques for an important role in cryptography — a key derivation.