NAME

       6tunnel - tunnelling for applications that don’t speak IPv6

SYNOPSIS

       6tunnel  [ -146dhfv ] [ -u username ] [ -i password ] [ -I password ] [
       -l local_host ] [ -L limit ]  [  -m  map_file  ]  ]  [  -p  pid_file  ]
       local_port remote_host [ remote_port ]

DESCRIPTION

       6tunnel  allows  you  to  use  services  provided  by  IPv6  hosts with
       IPv4-only applications and vice-versa. It can bind to any of your  IPv4
       (default)  or  IPv6  addresses  and  forward  all  data to IPv4 or IPv6
       (default) host. For example

              6tunnel -1 6668 irc6.net 6667

       will be enough to connect to IPv6 irc server with

              irc foobar localhost:6668

       If you don’t wish to run 6tunnel every  time  you  want  to  show  your
       :c001:  or  :dead: IPv6 address on IRC, you can use -i parameter, which
       makes 6tunnel ask your client for specified password. Just run

              6tunnel -i dupa.8 31337 irc6.net 6667

       and then type

              irc foobar localhost:31337:dupa.8

       If your IRC server requires you to send password, specify  it  with  -I
       parameter -- after successful proxy authentication 6tunnel will send it
       to the server.

       6tunnel can also be used as a tunnel for all other combinations of IPv4
       and  IPv6  endpoints.  If  remote host doesn’t have any IPv6 addresses,
       6tunnel will use the IPv4 one. In other cases, use -4  parameter  which
       makes  IPv4  address  the preffered one. For IPv6-to-any tunnels use -6
       which makes 6tunnel bind to IPv6 address.

OPTIONS

       -1     Exit after first connection.

       -4     Preffer IPv4 endpoint if the machine has both address types.

       -6     Listen on IPv6 address (IPv4 is default).

       -d     Don’t detach.

       -f     Force tunneling even if remote host is  not  resolvable  at  the
              execution time.

       -h     Print hex dump of every packet received or sent (hu-huh, Beavis,
              he said hex dump!)

       -u username
              Change UID and GID after bind().

       -i password
              Act as an IRC proxy and require user to authenticate.

       -I password
              If you are using 6tunnel as an IRC  proxy  and  the  IRC  server
              requires you to send password, place it right here.

       -l local_host
              Listen on specified address (IPv4, or IPv6 if -6 used).

       -L limit
              Limit simultaneous connections.

       -m map_file
              Bind  to  different  IPv6  addresses, depending on client’s IPv4
              address.  Example file format:

              127.0.0.1 3ffe:8010:7::3
              192.168.16.2 3ffe:8010:7::5

              With this option specified connections will be allowed only from
              listed  hosts.  To  allow  any  host  to connect you have to add
              mapping for 0.0.0.0 address.

       -p pid_file
              Write down pid to specified file.

       -s source_host
              Connect to the remote host using specified source address.

       -v     Be verbose and don’t detach.

SIGNALS

       Sending a SIGHUP signal forces a reload of the map file.

THANKS

       #ipv6 crew, Lam.

BUGS

       Terrible man page. Hex dump doesn’t include IRC  proxy  authentication.
       IRC  proxy  requires  your  client  to send password first (don’t worry
       ircii, EPIC, BitchX, mIRC and many more will work). No  logging  except
       debug output.

AUTHORS

       Wojtek  Kaniewski (wojtekka@bydg.pdi.net), Tomek Lipski (lemur@irc.pl),
       Dariusz    Jackowski     (ascent@linux.pl),     Ramunas     Lukosevicus
       (lukoramu@parok.lt)

SEE ALSO

       ssh(1)

                                  Apr 9, 2004                       6TUNNEL(1)