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ipmon(8)							      ipmon(8)

NAME
       ipmon - monitors	/dev/ipl for logged packets

SYNOPSIS
       ipmon  [	-abDFhnpstvxX ]	[ -N <device> ]	[ -o [NSI] ] [ -O [NSI]	] [ -P
       <pidfile> ] [ -S	<device> ] [ -f	<device> ] [ <filename>	]

DESCRIPTION
       ipmon opens /dev/ipl for	reading	and awaits data	to be saved  from  the
       packet  filter.	 The  binary data read from the	device is reprinted in
       human readable for, however, IP#'s are not mapped  back	to  hostnames,
       nor  are	 ports mapped back to service names.  The output goes to stan-
       dard output by default or a filename, if	given  on  the	command	 line.
       Should  the  -s	option	be used, output	is instead sent	to syslogd(8).
       Messages	sent via syslog	have the day, month and	year removed from  the
       message,	but the	time (including	microseconds), as recorded in the log,
       is still	included.

       Messages	generated by ipmon consist  of	whitespace  separated  fields.
       Fields common to	all messages are:

       1.  The	date of	packet receipt.	This is	suppressed when	the message is
       sent to syslog.

       2. The time of packet receipt. This is  in  the	form  HH:MM:SS.F,  for
       hours, minutes seconds, and fractions of	a second (which	can be several
       digits long).

       3. The name of the interface the	packet was processed on, e.g., we1.

       4. The group and	rule number of the rule, e.g.,	@0:17.	These  can  be
       viewed with ipfstat -n.

       5. The action: p	for passed, b for blocked, S for a short packet, n did
       not match any rules, L for a log	rule.	The  order  of	precedence  in
       showing	flags  is:  S,	p,  b,	n, L.  A capital P or B	means that the
       packet has been logged due to a global logging setting, not a  particu-
       lar rule.

       6.  The	addresses.   This is actually three fields: the	source address
       and port	(separated by a	comma),	the ->	symbol,	 and  the  destination
       address and port. E.g.: 209.53.17.22,80 -> 198.73.220.17,1722.

       7. PR followed by the protocol name or number, e.g., PR tcp.

       8.  len	followed  by the header	length and total length	of the packet,
       e.g., len 20 40.

       If the packet is	a TCP packet, there will be an additional field	start-
       ing  with  a hyphen followed by letters corresponding to	any flags that
       were set.  See the ipf.conf manual page for a list of letters and their
       flags.

       If  the	packet is an ICMP packet, there	will be	two fields at the end,
       the first always	being `icmp', and the next being the ICMP message  and
       submessage  type,  separated  by	 a  slash,  e.g.,  icmp	3/3 for	a port
       unreachable message.

       In order	for ipmon to properly work,  the  kernel  option  IPFILTER_LOG
       must  be	 turned	 on  in	 your  kernel.	Please see options(4) for more
       details.

OPTIONS
       -a     Open all of the device logfiles for reading  log	entries	 from.
	      All entries are displayed	to the same output 'device' (stderr or
	      syslog).

       -b     For rules	which log the body of a	packet,	 generate  hex	output
	      representing the packet contents after the headers.

       -D     Cause  ipmon  to	turn itself into a daemon.  Using subshells or
	      backgrounding of ipmon is	not required to	turn it	into an	orphan
	      so it can	run indefinitely.

       -f <device>
	      specify  an  alternative	device/file from which to read the log
	      information for normal IP	Filter log records.

       -F     Flush the	current	 packet	 log  buffer.	The  number  of	 bytes
	      flushed is displayed, even should	the result be zero.

       -n     IP  addresses  and  port numbers will be mapped, where possible,
	      back into	hostnames and service names.

       -N <device>
	      Set the logfile to be opened for reading NAT log records from to
	      <device>.

       -o     Specify  which  log  files  to actually read data	from.  N - NAT
	      logfile, S - State logfile, I - normal IP	Filter	logfile.   The
	      -a option	is equivalent to using -o NSI.

       -O     Specify  which  log files	you do not wish	to read	from.  This is
	      most sensibly used with the -a.  Letters available as parameters
	      to this are the same as for -o.

       -p     Cause  the port number in	log messages to	always be printed as a
	      number and never attempt to look it up  as  from	/etc/services,
	      etc.

       -P <pidfile>
	      Write  the  pid of the ipmon process to a	file.  By default this
	      is //etc/opt/ipf/ipmon.pid (Solaris), /var/run/ipmon.pid	(44BSD
	      or later)	or /etc/ipmon.pid for all others.

       -s     Packet  information  read	in will	be sent	through	syslogd	rather
	      than saved to a file.  The default facility  when	 compiled  and
	      installed	is security.  The following levels are used:

	      LOG_INFO	- packets logged using the "log" keyword as the	action
	      rather than pass or block.

	      LOG_NOTICE - packets logged which	are also passed

	      LOG_WARNING - packets logged which are also blocked

	      LOG_ERR -	packets	which have been	logged and which can  be  con-
	      sidered "short".

       -S <device>
	      Set  the logfile to be opened for	reading	state log records from
	      to <device>.

       -t     read the input file/device in a manner akin to tail(1).

       -v     show tcp window, ack and sequence	fields.

       -x     show the packet data in hex.

       -X     show the log header record data in hex.

DIAGNOSTICS
       ipmon expects data that it reads	to be consistent with how it should be
       saved  and will abort if	it fails an assertion which detects an anomaly
       in the recorded data.

FILES
       /dev/ipl
       /dev/ipnat
       /dev/ipstate
       /etc/services

SEE ALSO
       ipl(4), ipf(8), ipfstat(8), ipnat(8)

       If you find any,	please send email to me	at darrenr@pobox.com

								      ipmon(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | DIAGNOSTICS | FILES | SEE ALSO

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