Random data and key generation evaluation of some commercial tokens and smart cards

Abstract

In this paper, we report our evaluation of the strength of random number generator and RSA key-pair generator of some commercially available 1 constrained hardware modules, i.e., tokens and smart cards. That was motivated after recent related attacks to RSA public keys, which are generated by constrained network devices and smart cards, and turned out to be insecure due to low-quality randomness. Those attacks are mostly computing pair-wise GCD between the moduli in public keys, and resulted in breaking several thousands of these keys. Our results show that most of the tested hardware modules behave well. However, some have abnormal or weak random generators which seem to be unsuitable for cryptographic purposes. Moreover, another hardware module, in some rare circumstances, unexpectedly generates moduli which are divisible by very small prime factors.

E-BOOT: Preventing Boot-Time Entropy Starvation in Cloud Systems

“…From version 2.4, the UEFI specification [47] defines an entropy gathering protocol [48], designed for UEFI drivers to provide randomness to upper levels from its internal RNG. In addition, other devices as smart cards [49]- [51] and RNG tokens can be used as a entropy source. RNG tokens are typically attached to the machine via USB port [52], for example, the Altus Metrum ChaosKey [53] and YubiHSM [54].…”