dhan lin
2019-Jun-08 07:41 UTC
[Bridge] Originating device info for Packets trapped on Bridge
Hi All, I've a few doubts w.r.t layer2-frame processing in linux and PACKET_ORIGDEV socket option for getting origdev info. For example, lets assume below given is the set of net devices that my frame is intended to traverse over. eth0(1) -> bond0(2) -> bridge(3) -> vlan100(4). >>> (x) ifindex for each netdevice I have created a RAW socket ( not binded to any interface) , attached with a socket filter to trap only interested packets. I am getting a copy of frame trapped from each of the netdevice. is this expected? frame trapped from eth0 will have from.sll_ifindex=1 frame trapped from bond0 will have from.sll_ifindex=2 frame trapped from bridge will have from.sll_ifindex=3 frame trapped from vlan100 will have from.sll_ifindex=4 If I set the following socket option PACKET_ORIGDEV , I get the following result frame trapped from eth0 will have from.sll_ifindex=1 frame trapped from bond0 will have from.sll_ifindex=1 frame trapped from bridge will have from.sll_ifindex=3. >> why is this not set to 1 or 2? frame trapped from vlan100 will have from.sll_ifindex=3 can someone help me understand the role played by PACKET_ORIGDEV socket option in the above scenario. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.linuxfoundation.org/pipermail/bridge/attachments/20190608/5db0775d/attachment.html>