On Fri, Nov 06, 2026 at 09:21:32AM +0100, Hannes Reinecke wrote: > While I am pretty much in favour with this approach, is there a specific > reason why siphash has been chosen?
SipHash is the preferred choice for secure hash tables. It is secure, performs well on short inputs, and doesn't require special instructions. See Documentation/security/siphash.rst > Would there be a chance to make this configurable? > I do see slight complications when running in secure environments > (ie FIPS-certified environments) where most of the hash functions > might not be available ... SipHash support is available even when the kernel is booted with fips=1, so there's no issue there. It's already widely used in the kernel for hash tables, and that hasn't blocked FIPS certifications either. Side note: fips=1 actually has little do with security, and in some cases it actually decreases security. See for example https://lore.kernel.org/linux-crypto/[email protected]/ where I'm fixing a vulnerability caused by fips=1. - Eric
