On Thursday 18 August 2005 11:02 am, Dave Feustel wrote:
> On Thursday 18 August 2005 09:38, Dimitry Andric wrote:
> > See the atactl(8) manpage, in particular the sec* commands.
>
> I was looking that that manpage yesterday. It confirms that it
> is possible to make the disk data inaccessible to anyone without
> the user password.
>
> > However, I don't believe these harddisks actually encrypt all data on the
> > disk, so it's not really a security measure.
>
> OK. How long will it take you to get data off a disk made maximally secure
> via atactl commands? (Answer: most likely you won't get the data, ever).
> Also note that if atactl is used to set the user disk password, you
> will not be able to boot from a computer with a bios that doesn't offer you
> the opportunity to type in the user password you set while the system was
> running. That's what the 'freeze' command is for. (You did read about the
> freeze command, right?)
>
> > By zapping the firmware, or triggering some other magic switch, you're
> > probably always able to unlock these disks.
>
> That does seem to be the case right now for at least one company
> specializing in disk data recovery. But that approach to getting the data
> is expensive and time consuming. In other words: forget about getting
> access to password-protected disk data with a screwdriver and another
> computer.

The only way to recover information off of a disk that has the ata security 
password protection implemented correctly is to transplant the platters into 
another disk (of the same type).  IIRC, if the security spec is implemented 
correctly then just changing the external controller is not enough to allow 
the password to be bypassed and swapping the platters into another disk is 
not a trivial task.  It is not encrypted, but the controller will refuse to 
read information off of the disk.  

Tim Donahue

Reply via email to