RE: [Bluez-devel] Alignment issue

David Woodhouse
2004-08-13T08:07:45Z

On Thu, 2004-08-12 at 15:36 +0200, Marcel Holtmann wrote:
> I looked at the patches from the bluez-utils source RPM and actually I
> can include optional PIE support for you. A simple patch for that is
> easy and actually I already did that. From what I saw, this is a GCC 3.4
> only feature and you give -pie at linking time and not at compile time
> of the sources itself. Is this correct?

You also need -fpic in CFLAGS, I believe.

> What is the best way to detect PIE support in the compiler?

I hate myself for saying it, but possibly just test whether you can
actually build an executable that way?

> And please don't do this
>
> # Authentication and Encryption
> - #auth enable;
> - #encrypt enable;
> + auth enable;
> + encrypt enable;
>
> in the bluez-utils-2.3-conf.patch. If you do that then you are going to
> set your local device in security mode 3 and this is not what you want.

Hmmm, OK.... /me refers to Google and then
http://www.niksula.cs.hut.fi/~jiitv/bluesec.html

Don't I want that? If I were to leave it out, would that leave it in
mode 1, and mean I wouldn't be required to exchange a PIN with _every_
device before I can communicate with it at all?

The gnome-bluetooth program has been known to register its OBEX file
receive service and then just dump stuff into the user's home directory
-- even files with names like .rhosts :) If I make the requested change,
would that mean that _anyone_ can exploit this, rather than only devices
with which we're already paired?

Or am I getting confused? Can we do security mode 2?

I have a _vague_ recollection that there were devices I couldn't
communicate with unless I enabled those -- but it was a long time ago
and perhaps it was just that I thought authentication and encryption
sounded like good things so I should probably enable them :)

--
dwmw2