Re: pgcrypto seeding problem when ssl=on

On Mon, Jan 14, 2013 at 12:46 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Marko Kreen <markokr(at)gmail(dot)com> writes:
>> On Fri, Dec 21, 2012 at 10:27 PM, Noah Misch <noah(at)leadboat(dot)com> wrote:
>>> How about instead calling RAND_cleanup() after each backend fork?
>
>> Attached is a patch that adds RAND_cleanup() to fork_process().
>
> I remain unconvinced that this is the best solution. Anybody else have
> an opinion?

Do you have knowledge about systems that have /dev/random (blocking)
but not /dev/urandom (non-blocking)? The only argument I see against
RAND_cleanup() is that postgres might eat entropy from /dev/random (blocking)
and cause both other programs and itself block, waiting for more entropy.

But this can only happen on systems that don't have /dev/urandom.

Note: reading from /dev/urandom does not affect /dev/random.

--
marko