GPU Acceleration of RSA is Vulnerable to Side-channel Timing Attacks

The RSA algorithm [21] is a public-key cipher widely used in digital signatures and Internet protocols, including the Security Socket Layer (SSL) and Transport Layer Security (TLS). RSA entails excessive computational complexity compared with symmetric ciphers. For scenarios where an Internet domain is handling a large number of SSL connections and generating digital signatures for a large number of files, the amount of RSA computation becomes a major performance bottleneck. With the advent of general-purpose GPUs, the performance of RSA has been improved significantly by exploiting parallel computing on a GPU [9], [18], [23], [26], leveraging the Single Instruction Multiple Thread (SIMT) model.