ROSITA: Towards Automatic Elimination of Power-Analysis Leakage in Ciphers

Abstract

Since their introduction over two decades ago, sidechannel attacks have presented a serious security threat. While many ciphers’ implementations employ masking techniques to protect against such attacks, they often leak secret information due to unintended interactions in the hardware. We present ROSITA, a code rewrite engine that uses a leakage emulator which we amend to correctly emulate the micro-architecture of a target system. We use ROSITA to automatically protect masked implementations of AES, ChaCha, and Xoodoo. For AES and Xoodoo, we show the absence of observable leakage at 1 000 000 traces with less than 21% penalty to the performance. For ChaCha, which has significantly more leakage, ROSITA eliminates over 99% of the leakage, at a performance cost of 64%.