1 4d1f5654 2022-07-06 op .\" Copyright (c) 2021, 2022 Omar Polo <op@omarpolo.com>
  2 b542d800 2021-11-20 op .\"
  3 b542d800 2021-11-20 op .\" Permission to use, copy, modify, and distribute this software for any
  4 b542d800 2021-11-20 op .\" purpose with or without fee is hereby granted, provided that the above
  5 b542d800 2021-11-20 op .\" copyright notice and this permission notice appear in all copies.
  6 b542d800 2021-11-20 op .\"
  7 b542d800 2021-11-20 op .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  8 b542d800 2021-11-20 op .\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  9 b542d800 2021-11-20 op .\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 10 b542d800 2021-11-20 op .\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 11 b542d800 2021-11-20 op .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 12 b542d800 2021-11-20 op .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 13 b542d800 2021-11-20 op .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 14 4d1f5654 2022-07-06 op .Dd $Mdocdate: July 6 2022$
 15 b542d800 2021-11-20 op .Dt LSTUN 1
 16 b542d800 2021-11-20 op .Os
 17 b542d800 2021-11-20 op .Sh NAME
 18 b542d800 2021-11-20 op .Nm lstun
 19 b542d800 2021-11-20 op .Nd lazy ssh tunnel
 20 b542d800 2021-11-20 op .Sh SYNOPSIS
 21 b542d800 2021-11-20 op .Nm
 22 b542d800 2021-11-20 op .Bk -words
 23 3376f40a 2021-11-25 op .Op Fl dv
 24 8947862e 2021-11-23 op .Fl B Ar sshaddr
 25 b542d800 2021-11-20 op .Fl b Ar addr
 26 b542d800 2021-11-20 op .Op Fl t Ar timeout
 27 b542d800 2021-11-20 op .Ar destination
 28 b542d800 2021-11-20 op .Ek
 29 b542d800 2021-11-20 op .Sh DESCRIPTION
 30 b542d800 2021-11-20 op .Nm
 31 b542d800 2021-11-20 op binds the local
 32 b542d800 2021-11-20 op .Ar addr
 33 b542d800 2021-11-20 op and lazily spawns an
 34 b542d800 2021-11-20 op .Xr ssh 1
 35 b542d800 2021-11-20 op instance to forward the traffic to a remote end.
 36 b542d800 2021-11-20 op After
 37 b542d800 2021-11-20 op .Ar timeout
 38 b542d800 2021-11-20 op seconds
 39 b542d800 2021-11-20 op from the last client activity, the ssh tunnel is closed.
 40 b542d800 2021-11-20 op .Pp
 41 b542d800 2021-11-20 op The
 42 b542d800 2021-11-20 op .Xr ssh 1
 43 b542d800 2021-11-20 op tunnel is established by running
 44 b542d800 2021-11-20 op .Bk
 45 14151a45 2021-11-25 op .Pa ssh
 46 8947862e 2021-11-23 op .Fl L Ar sshaddr
 47 b542d800 2021-11-20 op .Fl NTq
 48 b542d800 2021-11-20 op .Ar destination .
 49 b542d800 2021-11-20 op .Ek
 50 b542d800 2021-11-20 op .Pp
 51 b542d800 2021-11-20 op The arguments are as follows:
 52 b542d800 2021-11-20 op .Bl -tag -width Ds
 53 8947862e 2021-11-23 op .It Fl B Xo
 54 8947862e 2021-11-23 op .Sm off
 55 8947862e 2021-11-23 op .Oo Ar bind_address : Oc
 56 8947862e 2021-11-23 op .Ar port : host : hostport
 57 8947862e 2021-11-23 op .Sm on
 58 8947862e 2021-11-23 op .Xc
 59 b542d800 2021-11-20 op Fed to
 60 b542d800 2021-11-20 op .Xr ssh 1
 61 b542d800 2021-11-20 op .Fl L
 62 b542d800 2021-11-20 op flag.
 63 c5cb3a17 2022-07-05 op .It Fl b Oo Ar host : Oc Ns Ar port
 64 b542d800 2021-11-20 op Where to bind the local socket.
 65 3376f40a 2021-11-25 op .It Fl d
 66 3376f40a 2021-11-25 op Do not daemonize.
 67 3376f40a 2021-11-25 op .Nm
 68 3376f40a 2021-11-25 op will run in the foregound and log to
 69 3376f40a 2021-11-25 op .Em stderr .
 70 b542d800 2021-11-20 op .It Fl t Ar timeout
 71 534c038e 2021-11-25 op Number of seconds after the last client shutdown to kill the ssh
 72 b542d800 2021-11-20 op process.
 73 85b8fe26 2021-11-25 op Set to zero to keep the tunnel open indefinitely.
 74 dd30c95b 2021-12-01 op Defaults to 600
 75 dd30c95b 2021-12-01 op .Pq ten minutes .
 76 3376f40a 2021-11-25 op .It Fl v
 77 3376f40a 2021-11-25 op Produce more verbose output.
 78 b542d800 2021-11-20 op .El
 79 68d87340 2021-11-25 op .Sh EXAMPLES
 80 3b34280e 2022-07-05 op Forward traffic on the local port 2525 to the remote port 25
 81 3b34280e 2022-07-05 op .Po the port 2526 is binded by ssh while
 82 68d87340 2021-11-25 op .Nm
 83 68d87340 2021-11-25 op listens on 2525 and forwards the traffic
 84 68d87340 2021-11-25 op .Pc
 85 68d87340 2021-11-25 op .Bd -literal -offset indent
 86 68d87340 2021-11-25 op $ lstun -B 2526:localhost:25 -b 2525 example.com
 87 68d87340 2021-11-25 op .Ed
 88 4d1f5654 2022-07-06 op .Sh SEE ALSO
 89 4d1f5654 2022-07-06 op .Xr ssh 1
 90 b542d800 2021-11-20 op .Sh AUTHORS
 91 b542d800 2021-11-20 op .An -nosplit
 92 b542d800 2021-11-20 op The
 93 b542d800 2021-11-20 op .Nm
 94 b542d800 2021-11-20 op utility was written by
 95 b542d800 2021-11-20 op .An Omar Polo Aq Mt op@omarpolo.com .
 96 236c6984 2021-11-21 op .Sh CAVEATS
 97 4caeea22 2021-11-21 op Currently it's impossible to pass flags to the
 98 4caeea22 2021-11-21 op .Xr ssh 1
 99 534c038e 2021-11-25 op sub command.
100 4caeea22 2021-11-21 op This is especially painful when you need to use, say, a jump host.