ORSCA-GPU: one round stream cipher algorithm for GPU implementation

Data confidentiality is one of the most critical security services. Many encryption algorithms are currently used to provide data confidentiality. That is why there are continuous research efforts on the design and implementation of efficient cipher schemes. For this purpose, different lightweight cipher algorithms have been presented and implemented on GPUs with different optimizations to reach high performance. Some examples of these ciphers are Speck, Simon which both require less latency compared to Advanced Encryption Standard (AES). However, these solutions require a higher number of rounds but with a more simple round function compared to AES. Therefore, in this paper, a new cipher scheme called ``ORSCA'' is defined which only requires one round with the dynamic key-dependent approach. The proposed cipher is designed according to the GPU characteristics. The proposed one-round stream cipher solution is suitable for the high data rate applications. According to the performance results, it can achieve high data throughput compared to existing ones, with throughput greater than 5 Terabits/s on a Tesla A100 GPU. Thus, this approach can be considered as a promising candidate for real-time applications. Finally, the security level is ensured by using the dynamic cryptographic primitives that can be changed for each new input message (or for a set of messages: sub-session key). Thus, the proposed solution is a promising candidate for high secure GPU cryptographic algorithms.