Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
PFLOG(4)		    Kernel Interfaces Manual		      PFLOG(4)

NAME
       pflog --	packet filter logging interface

SYNOPSIS
       device pflog

DESCRIPTION
       The  pflog interface is a device	which makes visible all	packets	logged
       by the packet filter, pf(4).  Logged packets can	easily be monitored in
       real time by invoking tcpdump(1)	on the pflog interface,	or  stored  to
       disk using pflogd(8).

       The  pflog0  interface is created when the pflog	module is loaded; fur-
       ther instances can be created using ifconfig(8).	 The pflog  module  is
       loaded automatically if both pf(4) and pflogd(8)	are enabled.

       Each packet retrieved on	this interface has a header associated with it
       of  length PFLOG_HDRLEN.	 This header documents the address family, in-
       terface name, rule number, reason, action, and direction	of the	packet
       that  was  logged.   This  structure, defined in	<net/if_pflog.h> looks
       like

	     struct pfloghdr {
		     u_int8_t	     length;
		     sa_family_t     af;
		     u_int8_t	     action;
		     u_int8_t	     reason;
		     char	     ifname[IFNAMSIZ];
		     char	     ruleset[PF_RULESET_NAME_SIZE];
		     u_int32_t	     rulenr;
		     u_int32_t	     subrulenr;
		     uid_t	     uid;
		     pid_t	     pid;
		     uid_t	     rule_uid;
		     pid_t	     rule_pid;
		     u_int8_t	     dir;
		     u_int8_t	     pad[3];
		     u_int32_t	     ridentifier;
	     };

EXAMPLES
       Create a	pflog interface	and monitor all	packets	logged on it:

	     # ifconfig	pflog create
	     pflog1
	     # ifconfig	pflog1 up
	     # tcpdump -n -e -ttt -i pflog1

SEE ALSO
       tcpdump(1),  inet(4),  inet6(4),	  netintro(4),	 pf(4),	  ifconfig(8),
       pflogd(8)

HISTORY
       The pflog device	first appeared in OpenBSD 3.0.

BUGS
       FreeBSD does not	set a process id in the	pid field in pfloghdr.

FreeBSD	13.2		       October 29, 2021			      PFLOG(4)

NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | SEE ALSO | HISTORY | BUGS

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=pflog&manpath=FreeBSD+14.2-RELEASE+and+Ports>

home | help