svn commit: r317015 - in head/sys: boot/forth conf crypto/chacha20 dev/random libkern sys

[Mark R V Murray]

> On 16 Apr 2017, at 13:30, Rodney W. Grimes <freebsd at pdx.rh.CN85.dnsmgr.net> wrote:
> 
>> The RC4 algorithm is standard. Making the alogorithm pluggable means more
>> code, more testing and more time (time which I am rather short of).
> 
> I would rather see a proper implementation later, than a poor design
> decision today.

I would love to see a perfect solution too. As I don't have the time for it,
I took the time to get a working solution reviewed and pretty heavily tested.
Reviewed by SO@, that is.

>>> Also you can always compile in a module, you can not compile out
>>> a 'standard' file.
>>> 
>>> For now could you just add
>>> 	options chacha #Required by arc4random, do not remove
>>> to your kernel and move on?  For me this would be an acceptable
>>> developement, even releasable, way to proceed while the more
>>> complex issue of how to make the kernel RNG use plagable lkm
>>> lower layers.
>> 
>> It would have to be unconditionally added to *all* kernels. Could be
>> done, I guess.
> 
> We dont have that many in base kernel configs do we?

No. But what about folks' own configs that break all-of-a-sudden? I've
been pretty angry n a few occasions when I'm trying to fix my own problems
and I had to waste time sorting out tangential, avoidable problems.

What's the difference between making this 'standard' in sys/files/conf
and adding a compulsory change to ALL kernel files (apart from the fact
that we miss the users' kernel configs)? We can even keep the
module stubs in the code. Later, when/if arc4random(9) becomes a loadable
module (I'd *LOVE* to see how we get that right without compromising
the RNG early start), we can make it optional. That is a one line change
to sys/conf/files.

>> RC4 has been standard for many years.
> Probably another rapid mode of design rather than a thoughful mode, we
> have a chance to correct this here, and imho, should.

Fix it, sure. What's wrong with doing that as a next step? Why does this
change need to be held to ransom?

>> Up until now, arc4random worked with unconditional RC4.
> 
> And your wanting to just replace unconditional RC4 for unconditional chacha?
> Or actuall, aleady did?

Correct. Both counts. It was up on Phabricator for weeks, BTW.

M
-- 
Mark R V Murray