.\" -*-nroff-*-
.\"
-.\" $Id: fw.1,v 1.9 2000/03/23 00:37:33 mdw Exp $
+.\" $Id: fw.1,v 1.15 2003/01/24 20:13:04 mdw Exp $
.\"
.\" Manual page for fw
.\"
.\" ---- Revision history ---------------------------------------------------
.\"
.\" $Log: fw.1,v $
+.\" Revision 1.15 2003/01/24 20:13:04 mdw
+.\" Fix bogus examples. Explain quoting rules for `exec' endpoints.
+.\"
+.\" Revision 1.14 2002/02/23 00:05:12 mdw
+.\" Fix spacing around full stops (at last!).
+.\"
+.\" Revision 1.13 2002/02/22 23:45:01 mdw
+.\" Add option to change the listen(2) parameter.
+.\"
+.\" Revision 1.12 2001/02/23 09:11:29 mdw
+.\" Update manual style.
+.\"
+.\" Revision 1.11 2001/02/05 19:47:11 mdw
+.\" Minor fixings to wording.
+.\"
+.\" Revision 1.10 2001/02/03 20:30:03 mdw
+.\" Support re-reading config files on SIGHUP.
+.\"
.\" Revision 1.9 2000/03/23 00:37:33 mdw
.\" Add option to change user and group after initialization. Naughtily
.\" reassign short equivalents of --grammar and --options.
.
.\"--------------------------------------------------------------------------
.
-.TH fw 1 "1 July 1999" fw
+.TH fw 1 "1 July 1999" "Straylight/Edgeware" "fw port forwarder"
.
.\"--------------------------------------------------------------------------
.SH NAME
.RB ` [ '
and
.RB ` ; ',
-require escaping by the shell, they are strictly optional in the grammar
-and can be omitted in quick hacks at the shell prompt.
+require escaping by the shell, they are mostly optional in the grammar
+and can tend to be omitted in quick hacks at the shell prompt.
.TP
.I "whitespace characters"
Whitespace characters separate words but are otherwise ignored. All
A global option, outside of a
.I fw-stmt
has no context unless it is explicitly qualified, and affects global
-behaviour. Local options, applied to a source or target in a
-.I fw-stmt
+behaviour. A local option, applied to a source or target in a
+.IR fw-stmt ,
has the context of the type of source or target to which it is applied,
and affects only that source or target.
.PP
.br
|
.I prefix
-.B .
+.B .\&
.I q-option
.br
|
cpu = 60;
}
.VE
-is equivalent to
+means the same as
.VS
exec.rlimit.core = 0;
exec.rlimit.cpu = 0;
.I file
::=
.B file
-.RB [ . ]
+.RB [ .\& ]
.I fspec
.RB [ ,
.IR fspec ]
.I exec
::=
.BR exec
-.RB [ . ]
+.RB [ .\& ]
.I cmd-spec
.br
.I cmd-spec
.RI ( argv0 )
is used.
.PP
+Note that the shell command or program name string must, if present,
+have any delimiter characters (including
+.RB ` / '
+and
+.RB ` . ')
+quoted; this is not required in the
+.RB ` [ '-enclosed
+argument list.
+.PP
The standard input and output of the program are forwarded to the other
end of the connection. The standard error stream is caught by
.B fw
Sets the root directory for the program, using the
.BR chroot (2)
system call. You must be the superuser for this option to work. The
-default is not to set a root directory. The synonyms
-.BR cd ,
-.B chdir
-and
-.B cwd
-are accepted in place of
-.B dir .
+default is not to set a root directory. The synonym
+.B chroot
+is accepted in place of
+.BR root .
.OE
.OS "Exec options"
.B exec.user
.br
.I socket-source
::=
-.RB [ socket [ . ]]
+.RB [ socket [ .\& ]]
.RB [[ : ] \c
.IR addr-type \c
.RB [ : ]]
.br
.I socket-target
::=
-.RB [ socket [ . ]]
+.RB [ socket [ .\& ]]
.RB [[ : ] \c
.IR addr-type \c
.RB [ : ]]
option is not recommended.
.OE
.OS "Socket options"
+.B socket.listen
+.RB [ = ]
+.I number
+.OD
+Sets the maximum of the kernel incoming connection queue for this socket
+source. This is the number given to the
+.BR listen (2)
+system call. The default is 5.
+.OE
+.OS "Socket options"
.B socket.logging
.RB [ = ]
.BR yes | no
.br
.I addr-elt
::=
-.B .
+.B .\&
|
.I word
.GE
Sockets are removed if
.B fw
exits normally (which it will do if it runs out of sources or
-connections, or if killed by SIGINT or SIGTERM).
+connections, or if
+.B fw
+shuts down in a clean way).
.SH "EXAMPLES"
To forward the local port 25 to a main mail server:
.VS
To emulate
.BR cat (1):
.VS
-from stdin, null to null, stdout
+from file stdin, null to file null, stdout
.VE
.
.\"--------------------------------------------------------------------------
+.SH "SIGNAL HANDLING"
+.
+The
+.B fw
+program responds to various signals when it's running. If it receives
+.B SIGTERM
+or
+.BR SIGINT ,
+.B fw
+performs a
+.I graceful
+shutdown: it removes all of its sources, and will exit when no more
+connections are running. (Note that if the disposition
+.B SIGINT
+was to ignore it,
+.B fw
+does not re-enable the signal. You'll have to send
+.B SIGTERM
+in that case.) If
+.B fw
+receives
+.BR SIGQUIT ,
+it performs an
+.I abrupt
+shutdown: it removes all sources and extant connections and closes down
+more-or-less immediately.
+.PP
+Finally, if any configuration files (other than standard input) were
+provided to
+.B fw
+on its command line using the
+.B \-f
+option, a
+.B SIGHUP
+signal may be sent to instruct
+.B fw
+to reload its configuration. Any existing connections are allowed to
+run their course. If no such configuration files are available,
+.B fw
+just logs a message about the signal and continues.
+.PP
+.
+.\"--------------------------------------------------------------------------
.SH "GRAMMAR SUMMARY"
.
.SS "Basic syntax"
.br
|
.I prefix
-.B .
+.B .\&
.I q-option
.br
|
.I file
::=
.B file
-.RB [ . ]
+.RB [ .\& ]
.I fspec
.RB [ ,
.IR fspec ]
.I exec
::=
.BR exec
-.RB [ . ]
+.RB [ .\& ]
.I cmd-spec
.br
.I cmd-spec
.br
.I socket-source
::=
-.RB [ socket [ . ]]
+.RB [ socket [ .\& ]]
.RB [[ : ] \c
.IR addr-type \c
.RB [ : ]]
.br
.I socket-target
::=
-.RB [ socket [ . ]]
+.RB [ socket [ .\& ]]
.RB [[ : ] \c
.IR addr-type \c
.RB [ : ]]
.br
.I addr-elt
::=
-.B .
+.B .\&
|
.I word
.PP
.IR number | \c
.BR unlimited | one-shot
.br
+.B socket.listen
+.RB [ = ]
+.I number
+.br
.B socket.logging
.RB [ = ]
.BR yes | no
holes as a matter of priority when I find out about them. I will be
annoyed if I have to read about problems on Bugtraq because they weren't
mailed to me first.
+.PP
+The program is too complicated, and this manual page is too long.
.
.\"--------------------------------------------------------------------------
.SH "AUTHOR"