IPFWPCAP(8)             FreeBSD System Manager's Manual            IPFWPCAP(8)

NAME
     ipfwpcap - copy diverted packets to a file in tcpdump format

SYNOPSIS
     ipfwpcap [-dr] [-b maxbytes] [-p maxpkts] [-P pidfile] portnum dumpfile

DESCRIPTION
     The ipfwpcap utility is used to copy diverted packets to a file in
     tcpdump(1) format.  The interesting packets are diverted by ipfw(8) to a
     port on which ipfwpcap listens.  The packets are then dropped unless -r
     is used.

     The options are as follows:

     -d      Turns on extra debugging messages.

     -r      Writes packets back to the divert(4) socket.

     -rr     Indicates that it is okay to quit if maxbytes or maxpkts are
             reached.  Diverted packets will silently disappear if nothing is
             listening on the divert(4) socket.

     -b maxbytes
             Stop dumping after maxbytes bytes.

     -p maxpkts
             Stop dumping after maxpkt packets.

     -P pidfile
             File to store PID number in.  Default is
             /var/run/ipwfpcap.portnr.pid.

     The portnum argument specifies which divert(4) socket port to listen on.
     The dumpfile argument is the path to the file to write captured packets
     to.  Specify `-' to write to stdout.

EXIT STATUS
     The ipfwpcap utility exits 0 on success, and >0 if an error occurs.

EXAMPLES
           ipfwpcap -r 8091 divt.log &

     Starts ipfwpcap as a background job listening to port 8091 and reflecting
     the packets back to the socket.

           ipfw add 2864 divert 8091 ip from 192.0.2.101

     Example ipfw(8) rule to divert all packets from 192.0.2.101 to port 8091.
     See ipfw(8) for details.

SEE ALSO
     tcpdump(1), pcap(3), divert(4), ipfw(8)

HISTORY
     The ipfwpcap utility first appeared in FreeBSD 7.0.

AUTHORS
     ipfwpcap was written by P. Kern <pkern@cns.utoronto.ca>.  This manual
     page was written by Niclas Zeising <zeising@FreeBSD.org>.

FreeBSD 13.1-RELEASE-p6          May 22, 2006          FreeBSD 13.1-RELEASE-p6