Hi Johan, On Wed, Jul 20, 2016 at 10:39 AM, Johan Hedberg <johan.hedberg@xxxxxxxxx> wrote: > Hi Alex, > > On Tue, Jul 19, 2016, Alexander Aring wrote: >> mhhh, I am not a bluetooth expert. What really means "periodically >> change is RPA" and how is this done in the Linux bluetooth? >> >> When "changing the RPA" happens, does that mean the all connections will >> be lost (unregister interface). Then the previous connections will be >> recreated (register interface) with a complete different MAC address? > > Connections aren't lost when the random address is changed. That's why > we track the hci_conn->init_addr and hci_conn->resp_addr. The way this > is dealt with e.g. the Security Manager protocol is that the connection > creation address *is* the address for the remote device throughout the > entire connection, no matter what happens to the local and remote random > address during the connection. I would expect 6LoWPAN do do something > similar. > > What was still unclear to me (maybe I missed it in the thread): does the > 6LoWPAN for LE spec require using the connection creation address or the > identity address? If it would be the latter then that's something that > will never change and the whole interface recreation issue goes away. For the MAC address I don't really know, but for the link-local IPv6 address I think the RPA shall be used: 'The IPv6 link-local address configuration described in Section 3.2.2 only reveals information about the 6LN to the 6LBR that the 6LBR already knows from the link-layer connection. This means that a device using Bluetooth privacy features reveals the same information in its IPv6 link-local addresses as in its device addresses. Respectively, a device not using privacy at the Bluetooth level will not have privacy at the IPv6 link-local address either.' -- Luiz Augusto von Dentz -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
