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Re: Building a distribution from source?



Steve Kemp <skx@debian.org> writes:

> On Fri, Dec 05, 2003 at 12:10:44PM +1100, Russell Coker wrote:
> > On Fri, 5 Dec 2003 10:39, Steve Kemp <skx@debian.org> wrote:
> > > ? I've been experimenting with producing a hardened Debian derivitive
> > > ?as a small piece of paid work. ?This mostly means compiling things with
> > > ?a stackguard compiler, using format guard, and enforcing policies, etc.
> > 
> > Are you using any extra patches to GCC?  Or just a GCC built with the 
> > propolice option?
> 
>   Yes I am using slightly modified patches from http://www.immunix.org/.
> 
>   The propolice is something that I shall be evaluating next.
> 
> > How difficult is it to bootstrap this?  Can you compile glibc with these 
> > options without affecting anything else?
> 
>   So far I have built glibc with this modified GCC, (only so that I
>  could apply the "FormatGuard" patches which are designed to combat
>  format string attacks.  Recompiling glibc wasn't something that I
>  really wanted to try on the PII 233Mhz machine I have as my test box!
> 
>   Bootstrapping was very simple just a matter of applying the patche to
>  GCC and rebuilding it, then having installed it I rebuilt several test
>  packages which were exploitable previously and failed to be exploitable
>  afterwards.  (With the caveats that this patch doesnt protect against
>  all attacks).
> 
>   I confess that I haven't rebuilt _all_ the interesting packages yet
>  the kernel and X11 being the most likely to fail - but the packages
>  that I did build, bash, perl, etc did compile with no observed side
>  effects thus far.

If the ABI of libraries stays the same, sounds that way, bootstraping
is realy easy.

You can setup a normal system with wanna-build and a buildd and an
empty archive. You should patch the buildd to add a -0.0.1 or .0.1
debian version to each build. That way you can have the normal and
your hardened repository in the apt/sources.lists, install
normaly/security updates imediatly and update to hardened versions as
they are available.

MfG
        Goswin



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