Harnessing Lightweight Ciphers for PDF Encryption

Portable Document Format (PDF) is a file format which is used worldwide as de-facto standard for exchanging documents. In fact this document that you are currently reading has been uploaded as a PDF. Confidential information is also exchanged through PDFs. According to PDF standard ISO 3000-2:2020, PDF supports encryption to provide confidentiality of the information contained in it along with digital signatures to ensure authenticity. At present, PDF encryption only supports Advanced Encryption Standard (AES) to encrypt and decrypt information. However, Lightweight Cryptography, which is referred to as crypto for resource constrained environments has gained lot of popularity specially due to the NIST Lightweight Cryptography (LWC) competition announced in 2018 for which ASCON was announced as the winner in February 2023. The current work constitutes the first attempt to benchmark Java implementations of NIST LWC winner ASCON and finalist XOODYAK against the current PDF encryption standard AES. Our research reveals that ASCON emerges as a clear winner with regards to throughput when profiled using two state-of-the-art benchmarking tools YourKit and JMH.