xref: /freebsd/usr.sbin/ipfwpcap/ipfwpcap.8 (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1.\" Copyright (c) 2006 Niclas Zeising <zeising@FreeBSD.org>
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25.\" $FreeBSD$
26.\"
27.Dd May 22, 2006
28.Dt IPFWPCAP 8
29.Os
30.Sh NAME
31.Nm ipfwpcap
32.Nd "copy diverted packets to a file in tcpdump format"
33.Sh SYNOPSIS
34.Nm
35.Op Fl dr
36.Op Fl b Ar maxbytes
37.Op Fl p Ar maxpkts
38.Op Fl P Ar pidfile
39.Ar portnum
40.Ar dumpfile
41.Sh DESCRIPTION
42The
43.Nm
44utility is used to copy diverted packets to a file in
45.Xr tcpdump 1
46format.
47The interesting packets are diverted by
48.Xr ipfw 8
49to a port on which
50.Nm
51listens.
52The packets are then dropped unless
53.Fl r
54is used.
55.Pp
56The options are as follows:
57.Bl -tag -width indent
58.It Fl d
59Turns on extra debugging messages.
60.It Fl r
61Writes packets back to the
62.Xr divert 4
63socket.
64.It Fl rr
65Indicates that it is okay to quit if
66.Ar maxbytes
67or
68.Ar maxpkts
69are reached.
70Diverted packets will silently disappear if nothing is listening on the
71.Xr divert 4
72socket.
73.It Fl b Ar maxbytes
74Stop dumping after
75.Ar maxbytes
76bytes.
77.It Fl p Ar maxpkts
78Stop dumping after
79.Ar maxpkt
80packets.
81.It Fl P Ar pidfile
82File to store PID number in.
83Default is
84.Pa /var/run/ipwfpcap.portnr.pid .
85.El
86.Pp
87The
88.Ar portnum
89argument specifies which
90.Xr divert 4
91socket port to listen on.
92The
93.Ar dumpfile
94argument is the path to the file to write captured packets to.
95Specify
96.Sq Fl
97to write to stdout.
98.Sh EXIT STATUS
99.Ex -std
100.Sh EXAMPLES
101.Dl "ipfwpcap -r 8091 divt.log &"
102.Pp
103Starts
104.Nm
105as a background job listening to port 8091 and reflecting the packets
106back to the socket.
107.Pp
108.Dl "ipfw add 2864 divert 8091 ip from 192.0.2.101"
109.Pp
110Example
111.Xr ipfw 8
112rule to divert all packets from 192.0.2.101 to port 8091.
113See
114.Xr ipfw 8
115for details.
116.Sh SEE ALSO
117.Xr tcpdump 1 ,
118.Xr pcap 3 ,
119.Xr divert 4 ,
120.Xr ipfw 8
121.Sh HISTORY
122The
123.Nm
124utility first appeared in
125.Fx 7.0 .
126.Sh AUTHORS
127.An -nosplit
128.Nm
129was written by
130.An P. Kern Aq Mt pkern@cns.utoronto.ca .
131This manual page was written by
132.An Niclas Zeising Aq Mt zeising@FreeBSD.org .
133