On Tue, Oct 27, 2015 at 6:57 PM, Eric Covener <cove...@gmail.com> wrote: > IIUC, it takes something like 32k of /dev/random to initialize apr_random. > > APR_RANDOM_DEFAULT_POOLS*APR_RANDOM_DEFAULT_RESEED_SIZE*APR_RANDOM_DEFAULT_G_FOR_INSECURE > (32*32*32) > > But ap_init_rng() does this with ~4000 8-byte reads of /dev/random. > > I am working on a platform where access to the crypto facility > underneath /dev/random is sometimes audited. Does anyone have any > hints about whether larger reads from /dev/random would be better > elsewhere? Or if the startup requirement is really this high for data > from /dev/random?
AFAICT, /dev/urandom itself only requires 256 bits (32 bytes) of (secret) entropy to be secure (cryptographically strong), so I don't think more would be needed for httpd (or APR). It seems to me that asking for more than 32 bytes of random bytes by something like a minute is not very sound (both for the requester AND the "others"), so IMHO we should really take that into consideration.
