1.\" $OpenBSD: pflog.4,v 1.10 2007/05/31 19:19:51 jmc Exp $ 2.\" 3.\" Copyright (c) 2001 Tobias Weingartner 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd May 31, 2007 29.Dt PFLOG 4 30.Os 31.Sh NAME 32.Nm pflog 33.Nd packet filter logging interface 34.Sh SYNOPSIS 35.Cd "device pflog" 36.Sh DESCRIPTION 37The 38.Nm pflog 39interface is a device which makes visible all packets logged by 40the packet filter, 41.Xr pf 4 . 42Logged packets can easily be monitored in real 43time by invoking 44.Xr tcpdump 1 45on the 46.Nm 47interface, or stored to disk using 48.Xr pflogd 8 . 49.Pp 50The pflog0 interface is created automatically at boot if both 51.Xr pf 4 52and 53.Xr pflogd 8 54are enabled; 55further instances can be created using 56.Xr ifconfig 8 . 57.Pp 58Each packet retrieved on this interface has a header associated 59with it of length 60.Dv PFLOG_HDRLEN . 61This header documents the address family, interface name, rule 62number, reason, action, and direction of the packet that was logged. 63This structure, defined in 64.Aq Pa net/if_pflog.h 65looks like 66.Bd -literal -offset indent 67struct pfloghdr { 68 u_int8_t length; 69 sa_family_t af; 70 u_int8_t action; 71 u_int8_t reason; 72 char ifname[IFNAMSIZ]; 73 char ruleset[PF_RULESET_NAME_SIZE]; 74 u_int32_t rulenr; 75 u_int32_t subrulenr; 76 uid_t uid; 77 pid_t pid; 78 uid_t rule_uid; 79 pid_t rule_pid; 80 u_int8_t dir; 81 u_int8_t pad[3]; 82}; 83.Ed 84.Sh EXAMPLES 85Create a 86.Nm 87interface 88and monitor all packets logged on it: 89.Bd -literal -offset indent 90# ifconfig pflog1 up 91# tcpdump -n -e -ttt -i pflog1 92.Ed 93.Sh SEE ALSO 94.Xr tcpdump 1 , 95.Xr inet 4 , 96.Xr inet6 4 , 97.Xr netintro 4 , 98.Xr pf 4 , 99.Xr ifconfig 8 , 100.Xr pflogd 8 101.Sh HISTORY 102The 103.Nm 104device first appeared in 105.Ox 3.0 . 106.\" .Sh BUGS 107.\" Anything here? 108