RE: [Bluez-devel] Service level security for RFCOMM

Stephen Crane
2004-11-01T12:02:31Z

Hi Marcel,

On Fri, 2004-10-29 at 17:40, Marcel Holtmann wrote:
> However this also leads to a security problem, because I can scan the
> RFCOMM ports of a remote device without forcing the security mechanism.
> I only have to do the PN exchange and then disconnect. What should a
> remote device do when a PN CMD comes in for a channel without a service
> behind it?

If the spec says that authentication can only happen on receipt of SABM,
then I guess this leaves it open to port scans.

However, does this really matter? If you want to protect _all_ services,
use security mode 3. If you're in security mode 2, it's most likely that
you can do SDP searches without performing a security procedure and
discover open channels that way.

> Sorry, I don't get the point. Why should a client care about security
> mode 2, when it want to connect to a server in security mode 1. Actually
> the server must know what services to protect and not the client. If you
> have such server running, then this is a wrong designed server from my
> point of view.

Well, for example, a client may wish to authenticate a server before
connecting to it, irrespective of the security the service wants for
itself.

> Regards
>
> Marcel

Steve
--
Stephen Crane, Rococo Software Ltd. http://www.rococosoft.com
steve.crane@rococosoft.com +353-1-6601315 (ext 209)