Re: [PATCH v2 1/4] siphash: add cryptographically secure hashtable function

Jason A. Donenfeld [off-list ref] wrote:

Siphash needs a random secret key, yes. The point is that the hash
function remains secure so long as the secret key is kept secret.
Other functions can't make the same guarantee, and so nervous periodic
key rotation is necessary, but in most cases nothing is done, and so
things just leak over time.

Actually those users that use rhashtable now have a much more
sophisticated defence against these attacks, dyanmic rehashing
when bucket length exceeds a preset limit.

Cheers,
-- 
Email: Herbert Xu [off-list ref]
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt