Kai Johnson

I hadn't really looked at what it might take to host it on SourceForge. Would you like to help with the setup?

Inconsistency in FF1 implementation

If you're performing operations that are within the range of the FF1 implementation, then I agree that you should use it rather than the FF1Parameters implementation for FFX. The FF1Parameters implementation demonstrates that it is possible to implement FF1 on FFX, but it's certainly not as well vetted as the NIST-approved FF1 algorithm. I'll close the ticket as you suggest. I'm curious what you're using FF1 for, though. FPE generally makes sense when you're forced into using a specific radix and...

The issue here is a subtle. FF1 is defined to use exactly ten rounds (i.e. iterations of the Feistel structure). FFX relies on the parameters to specify the number of rounds, and the FF1Parameters are hard coded to use ten rounds to match the FF1 specification. However, FFX also specifies lower bounds on the number of rounds to avoid known attacks. The lower bounds are specified at the bottom of p. 4 in The FFX Mode of Operation for Format-Preserving Encryption with some further discussion in Appendix...

Thanks for posting the issue and the source code. I'll take a look at it as soon as I get a chance, but it might be a couple of weeks.

Corrected parameters for NIST FF1 Sample #6.

rearrange code for build

Refactored from Android to POJO for standalone use.