|Summary:||ipfw can't distinguish an inbound packets forwarded via if_bridge|
|Product:||Base System||Reporter:||Alexander Zagrebin <alex>|
|Component:||kern||Assignee:||freebsd-ipfw (Nobody) <ipfw>|
|Severity:||Affects Many People||CC:||alex|
Description Alexander Zagrebin 2017-10-04 08:01:09 UTC
Created attachment 186898 [details] patch By default (when net.link.bridge.pfil_bridge=1), the packet, forwarded via if_bridge, has to be processed by ipfw 4 times. Suppose such configuration: em0 <-> bridge0 <-> em1 ipfw will process packet, forwarded from em0 to em1, in the following sequence: in[em0], in[bridge0], out[bridge0], out[em1]. We can expect, that inbound packets can be matched with the following ipfw rule options: in[em0] - 'in recv em0' or 'in via em0' in[bridge0] - 'in via bridge0' For example, ipfw add 1 count ip from any to any in via em0 ipfw add 2 count ip from any to any in via bridge0 but this doesn't work as expected: each single packet matches 2 times to the rule 1 and not matches to the rule 2 at all. The reason in the following: despite that if_bridge sends information about corresponding interface to the pfil_run_hooks(), the ipfw doesn't uses it while processing inbound packets. The attached patch fixes issue: If the interface on which ipfw processes packet does not match an 'received' interface, then this interface saved and used later in the processing of 'via' rule option.