Robert John Lambert

Securing the Elliptic Curve Montgomery Ladder against Fault Attacks

The Montgomery ladder method of computing elliptic curve scalar multiplication is esteemed as an efficient algorithm, inherently resistant to simple side-channel attacks as well as to various fault attacks. In FDTC 08, Fouque \etal present an attack on the Montgomery ladder in the presence of a point validation countermeasure, when the

A new CRT-RSA algorithm resistant to powerful fault attacks

y

AUTHENTICATION OF A MOBILE DEVICE BY A NETWORK AND KEY GENERATION

-coordinate is not used. In this paper, we present an efficient countermeasure that renders the algorithm resistant to this attack as well as to other known fault attacks.

Verifying a Wireless Device

CRT-RSA is widely deployed in embedded devices to accelerate the RSA signature generation by about four times compared to regular RSA. However, since the Bellcore attack of 1996, research into securing CRT-RSA has remained active as countermeasures are themselves attacked. In this paper, we propose a new countermeasure designed with a powerful attacker in mind. The attacker may inject multiple precise/random faults and may alter the program counter to skip one or more instructions. The strength of our countermeasure derives from combining signature validation with signature unblinding modulo n.