Return-Path: Subject: RE: [Bluez-devel] Service level security for RFCOMM From: Stephen Crane To: Marcel Holtmann Cc: Bhatt Abhi-ABHATT , BlueZ Mailing List In-Reply-To: <1099068050.10164.69.camel@pegasus> References: <5987A7CB1694D811A04D0002B32C289601BF3BFE@il93exb05.corp.mot.com> <1099061231.10164.62.camel@pegasus> <1099062653.28599.47.camel@baroque.rococosoft.com> <1099068050.10164.69.camel@pegasus> Content-Type: text/plain Message-Id: <1099310550.28599.132.camel@baroque.rococosoft.com> Mime-Version: 1.0 Date: Mon, 01 Nov 2004 12:02:31 +0000 List-ID: 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)