kern/177810: traffic dropped by accepting rules is not counted

[Kajetan Staszkiewicz]

>Number:         177810
>Category:       kern
>Synopsis:       traffic dropped by accepting rules is not counted
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Apr 12 15:40:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Kajetan Staszkiewicz
>Release:        9.1-RELEASE
>Organization:
InnoGames GmbH
>Environment:
FreeBSD xxxxxxx 9.1-RELEASE FreeBSD 9.1-RELEASE #10 r247265M: Mon Feb 25 14:58:39 CET 2013     root at xxxxxxx:/usr/obj/usr/src/sys/IGLB3  amd64
>Description:
Currently per-rule counting is performed only for packets that are accepted by any rule or any packets matched by a droping rule. Counting on per-interface basis is perfomed properly.

There are some possibilities for a packet do be dropped by an accepting rule and therefore not counted:

1. SYN/SYN+ACK/ACK packets going through synproxy are dropped with PF_SYNPROXY_DROP action. This generates new packets sent to client and server that are legitimate traffic and should be counted.

2. Creation of a state or a src-node might fail due to memory or per-rule state limits. This traffic is dropped (or at least should be, have a look on kern/177808), but still matched some rule. I believe it also should be counted, but this is open for discussion.
>How-To-Repeat:
SYN-flood your FreeBSD based machine with synproxy rules or rules with state limit, observe no increase of counters of `pfctl -sl`
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: