Welcome to the resource topic for 2025/1888
Title:
HCTR2-FP and HCTR3-FP: Format-Preserving Encryption from Wide-Block Ciphers
Authors: Frank Denis
Abstract:Format-preserving encryption (FPE) enables encryption while maintaining syntactic properties such as character sets. The current NIST standard FF1 uses multi-round Feistel networks that sacrifice performance for flexibility, while FF3-1 was withdrawn in 2025 following successful cryptanalytic attacks. FAST, proposed as a faster alternative, has not been widely implemented due to its complexity, leaving limited practical alternatives.
We present HCTR2-FP and HCTR3-FP, format-preserving adaptations of the HCTR2 and HCTR3 wide-block tweakable ciphers.
These variants preserve the single-pass Hash-Encrypt-Hash structure while operating on arbitrary radix domains through base-radix encoding and modular arithmetic. The constructions are simple to implement and analyze, and benchmarks demonstrate significant speedup over FF1.
ePrint: https://eprint.iacr.org/2025/1888
See all topics related to this paper.
Feel free to post resources that are related to this paper below.
Example resources include: implementations, explanation materials, talks, slides, links to previous discussions on other websites.
For more information, see the rules for Resource Topics .