.\" Copyright (c) 2021 Omar Polo <op@omarpolo.com>
.\"
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.Dd $Mdocdate: November 20 2021$
.Dt LSTUN 1
.Os
.Sh NAME
.Nm lstun
.Nd lazy ssh tunnel
.Sh SYNOPSIS
.Nm
.Bk -words
.Fl B Ar port:host:hostport
.Fl b Ar addr
.Op Fl t Ar timeout
.Ar destination
.Ek
.Sh DESCRIPTION
.Nm
binds the local
.Ar addr
and lazily spawns an
.Xr ssh 1
instance to forward the traffic to a remote end.
After
.Ar timeout
seconds
from the last client activity, the ssh tunnel is closed.
.Pp
The
.Xr ssh 1
tunnel is established by running
.Bk
.Pa /usr/bin/ssh
.Fl L Ar port:host:hostport
.Fl NTq
.Ar destination .
.Ek
.Pp
The arguments are as follows:
.Bl -tag -width Ds
.It Fl B Ar port:host:hostport
Fed to
.Xr ssh 1
.Fl L
flag.
.It Fl b Ar addr
Where to bind the local socket.
A port number or the tuple host:port.
.It Fl t Ar timeout
Number of seconds after after the last client shutdown to kill the ssh
process.
Defaults to 120.
.El
.Sh AUTHORS
.An -nosplit
The
.Nm
utility was written by
.An Omar Polo Aq Mt op@omarpolo.com .
.Sh CAVEATS
There's a 5 second timeout after spawning
.Xr ssh 1
to wait for the tunnel to be established.
It should really sleep for a little less
.Pq say one second
and then retry to connect multiple times until it succeed.