From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Layton Subject: Re: [PATCH] cifs: eliminate CONFIG_CIFS_WEAK_PW_HASH Date: Sat, 21 Jan 2012 07:37:20 -0500 Message-ID: <20120121073720.3cf546fc@tlielax.poochiereds.net> References: <1327091153-22391-1-git-send-email-jlayton@redhat.com> <20120120153856.6ded308a@tlielax.poochiereds.net> <1327118615.7985.5.camel@ruth> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Steve French , linux-cifs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, samba-technical To: Andrew Bartlett Return-path: In-Reply-To: <1327118615.7985.5.camel@ruth> Sender: linux-cifs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: On Sat, 21 Jan 2012 15:03:31 +1100 Andrew Bartlett wrote: > On Fri, 2012-01-20 at 14:45 -0600, Steve French wrote: > > My general thinking on this is as follows: > > > > If the kernel is distributed to all the workstations in an organization > > with this Kconfig option disabled, it makes it harder for individual users > > to make the mistake of enabling lanman (sec=lanman, or the Kconfig > > option) on a public network and thus send weak password hashes > > which could be discovered simply. Most distros make the choice > > of enabling broader compatibility with old pre-1997 servers but > > it is a very small set of servers who would require lanman support, > > and a large number of potential attackers who could benefit if > > users enable lanman on a public network. I suspect that there > > are environments where removing code (via Kconfig) is preferred > > to trusting all owners of all workstations running that organizations > > standard linux to never enable lanman at runtime. > > > > But ... the opinion of security specialists on this would be welcome. > > We have been though some of this with the kerberos libs, which now allow > (default?) to not even compile with weak crypto. If the weak crypto is > not compiled in, it can therefore be asserted that the weak crypto > cannot be used, and this makes it easier to comply with security > audits/certification etc. > > I don't want to make your code more complex than it needs to be, but LM > encryption really, really needs to go away. If it is not a major > bother, I would like to make it easier for that to happen if possible. > The only way for it to go away completely is for all servers that support only that encryption to go away completely. Unfortunately, that's a tall order -- there are still at least some in the field and people need to get at data on them. -- Jeff Layton