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 monitored in real time by invoking tcpdump(1) on the pflog interface, or stored to disk using pflogd(8).
Each packet retrieved on this interface has a header associated with it of length PFLOG_HDRLEN. This header documents the address family, interface 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;
u_int8_t dir;
u_int8_t pad[3];
};
EXAMPLES
# 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.