Re: PTS / linkkey issue

[Marcel Holtmann <marcel@holtmann.org>]

Hi Mike,

> >> I'm having a somewhat relate issue to Vishal AGARWAL [1].  The trouble
> >> I have is that the PTS system is requesting auth type 0, and Bluez
> >> happily obliges.  This leaves the PTS device as temporary, and BlueZ
> >> then deletes this device after the end of the connection.  This
> >> prevents me from being able to pass TP/OOR/BV-02-I: [HF reconnects to
> >> AG].  The code is designed to periodically reconnect to the AG after
> >> it detects a link timeout.  But, if BlueZ has deleted the device, I
> >> don't do that.  This also somewhat applies to the A2DP test cases, as
> >> my device must be left in pairing mode in order for the tests to pass.
> >>
> >> So, my question to people who have used PTS, is there a way to get the
> >> PTS to perform a pairing that is not 0x00 MITM Protection Not Required
> >> – No Bonding. Numeric comparison with automatic accept allowed?  I'm
> >> using an older kernel that doesn't have the mgmt interface (2.6.33
> >> with some features/fixes backported from newer kernels) but am using
> >> the latest BlueZ from git (at least of a month ago or so).  But even
> >> so, the proposal of keeping the linkkey around for the ACL session
> >> would be useless, I think, because the intent is to have a link
> >> timeout event.
> >
> > can you quickly check if for some weird reason the PTS uses debug keys
> > or if you enabled debug keys within BlueZ.
> >
> > We treat debug keys even worse than no bonding. Unless you set DebugKeys
> > in /etc/bluetooth/main.conf they are thrown out right away. However be
> > really careful here. That option is only for debugging. You should never
> > ever leave that on in a production device. You would make your device
> > vulnerable like no tomorrow.
>
> I checked hci dumps of both the init of my unit and the trace from the
> PTS run, and neither had sent the HCI_Write_Simple_Pairing_Debug_mode
> command.  Plus we can see that the key type is 0x04, Unauthenticated
> Combination Key.  I also verified that DebugKeys was false in
> main.conf.

please post the actual pairing exchange here, but this seems like the
PTS is fundamentally broken. If we pair with no bonding, we do throw the
link key away and that is suppose to be done this way.

Is there any chance to do a dedicated or general bonding with the PTS to
keep the link key around? Like you would actually be doing when using
any HFP device.

Regards

Marcel