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

Herbert Xu
2016-12-15T07:59:13Z

Jason A. Donenfeld <Jason@zx2c4.com> 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 <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt