I ran into a puzzling problem with an NKE that presents itself as a virtual Ethernet device. I wish that some Mac OS kernel guru out there would be able to shed some light on it. My NKE code is based on the Mac OS VLAN NKE code from the Darwin web site and the tunnel KEXT code (based on FreeBSD's tun driver). What the driver does is to function as an Ethernet device, except that frames sent through it are actually looped back to an application program where they are encapsulated before being transmitted through a real Ethernet interface, much like the ethertap driver does under Linux. I have set the source MAC address of the virtual Ethernet interface to be the same as its underlying real Ethernet device, and "ifconfig" seems to indicate that the MAC address is set properly. However, the problem is that the frames, such as ARP requests sent through this virtual Ethernet interface, have the source MAC address being something different from what it was set to. To be more specific, the source MAC address in the Ethernet header of the virtual Ethernet interface resembles the MAC address of the real Ethernet interface, i.e. 2 higher in the last digit. Changing the unit number of the virtual Ethernet interface doesn't make any difference at least on my ibook. I'm quite puzzled by this problem, and I'm hoping someone more familiar with Mac OS kernel internals could offer some advices on things for me to check. Any suggestion would be greatly appreciated! Joshua _______________________________________________ darwin-kernel mailing list | darwin-kernel@lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.