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PFLOG(4)	      DragonFly Kernel Interfaces Manual	      PFLOG(4)

NAME

pflog -- packet filter logging interface

SYNOPSIS

device pflog

DESCRIPTION

The pflog interface is a pseudo-device which makes visible all packets logged by the packet filter, pf(4). Logged packets can easily be moni- tored in real time by invoking tcpdump(1) on the pflog interface, or stored to disk using pflogd(8). The pflog0 interface is created automatically at boot if both pf(4) and pflogd(8) are enabled; further instances can be created using ifconfig(8). Each packet retrieved on this interface has a header associated with it of length PFLOG_HDRLEN. This header documents the address family, inter- face name, rule number, reason, action, and direction of the packet that was logged. This structure, defined in <net/pf/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]; };

EXAMPLES

Create a pflog interface and monitor all packets logged on it: # ifconfig pflog0 up # tcpdump -n -e -ttt -i pflog0

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 and was then integrated into DragonFly 1.1 by Devon H. O'Dell and Simon Schubert. DragonFly 4.1 December 10, 2001 DragonFly 4.1