From mboxrd@z Thu Jan 1 00:00:00 1970 From: Molle Bestefich Subject: Re: dm-crypt userland key patch Date: Fri, 15 Apr 2005 23:48:09 +0200 Message-ID: <62b0912f05041514485f38f872@mail.gmail.com> References: <20050413235852.45bd2500@emotpin> <62b0912f05041400135426a80e@mail.gmail.com> <20050414141459.6d521f67@emotpin> Reply-To: Molle Bestefich , device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <20050414141459.6d521f67@emotpin> Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Bjorn Andersson Cc: device-mapper development List-Id: dm-devel.ids Bjorn Andersson wrote: > > > Patch to the dm-crypt module so that it hides the crypto-key from > > > userland. (dmsetup table) > > > > Does it also overwrite the key in memory when unloading dm-crypt, mak= e > > sure that the memory is pinned so the key doesn't leak to swap, unloa= d > > the key before a 'hibernate', and that sort of stuff? > > No, this does only report a key of zeros when the status is requested. >=20 > The unloading thing is no problem to fix, but how should the > 'hibernate' thing work? When you resume after a 'hibernate' you probabl= y > expect that the device is there, especially if it's on the root > partition. But I clearly see your point. *Scratches head*, I'd expect the default to be "doing the safe thing", eg. picking up on hibernation and nuking the key (disabling any crypto devices). If there's a lean no-hassles user interface to get the password entered and the devices up again when the machine is resumed, I'd imagine most users to be happy about it, especially when they're told that it's done to protect their encrypted data? There might be a few people annoyed by it? Or there might even be some obscure technical reason why you'd want your keys to survive hibernation.. For those cases there could be an option to disable "hibernation protection" or what not. Dunno, IANA expert :-o.