Study on physical attack using electromagnetic wave against ring oscillator based true random number generator

 True random number generators (TRNGs) based on ring oscillators are employed in many devices because they can be constructed with logic gates only. Random numbers generated by TRNGs are used for various cryptographic systems as session keys, nonces, and masks. Among the physical attacks against TRNGs, frequency injection attacks degrade randomness by introducing a sinusoidal wave of a specific frequency to the device. However, previous studies have focused on the theory of attacks, and the kind of devices that are vulnerable to attacks has not been fully discussed. In this thesis, I will evaluate the security of TRNG which uses ring oscillators as entropy sources. Specifically, I will investigate the possibility of randomness degradation of TRNG using intentional electromagnetic interference and electromagnetic information leakage. I also aim to develop performance requirements and countermeasure technologies for equipment including TRNG that is resistant to physical attacks.