Messages in this thread | ![/](/images/icornerl.gif) | | Date | Fri, 15 Aug 2003 18:55:01 -0500 | From | Matt Mackall <> | Subject | Re: [RFC][PATCH] Make cryptoapi non-optional? |
| |
On Fri, Aug 15, 2003 at 06:12:11PM -0400, Theodore Ts'o wrote:
> However, if people insist on doing silly things like "cat > /dev/urandom > /dev/hda", and worse yet, screwing with the > /dev/random and /dev/urandom with the excuse that speed is of > importance, then perhaps following OpenBSD and implementing > /dev/frandom is a better choice.
Sigh..
I posted a proof of concept patch for discussion on $SUBJECT. In that patch, I removed the folding for the purposes of having a reasonable comparison between cryptoapi and native. Cryptoapi does FIPS-180-1 and thus does twice as much hashing on 512 bits. Removing the folding was a convenient and obvious way of addressing it for the purposes of discussing $SUBECT until a good way to work around the extra padding was found. I've already indicated my willingness to accept your SHA-may-be-backdoored-and-somehow-leverageable argument, so can we kindly discuss $SUBJECT instead of this trivia?
As for "screwing with /dev/random", it's got rather more serious and longstanding problems than speed that I've been addressing. For instance, I'm pretty sure there was never a time when entropy accounting wasn't racy let alone wrong, SMP or no (fixed in -mm, thank you). Nor has there ever been a time when change_poolsize() wasn't an oops waiting to happen (patch queued for resend).
And frankly, given that my local version of /dev/urandom does 18MB/s without starving /dev/random, I see no reason to reinvent strong PRNGs in userspace for most applications.
-- Matt Mackall : http://www.selenic.com : of or relating to the moon - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| ![\](/images/icornerr.gif) |