6TUNNEL(1)

NAME
6tunnel - tunnelling for application that don't speak IPv6

SYNOPSIS
6tunnel [ -146dhfvV ] [ -u username ] [ -i password ] [ -I password ] [ -l local_host ] [ -L limit ] [ -p pid_file ] [ -m map_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 preferred one. For IPv6-to-any tunnels use -6 which makes 6tunnel bind to IPv6 address.

OPTIONS

-1  Exit after first connection.

-4  Prefer 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.

-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.

-p pid_file
    Write down pid to specified file.

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

-m map_file
    Binds to specified IPv6 addresses on basis of source IPv4 address. The file contains one mapping per line with IPv4 source address and corresponding IPv6 address. Only listed hosts are allowed to connect. If you want to allow any host, add mapping for default or 0.0.0.0 address. Example:

    192.168.0.2 3ffe:8010:18::1000:2
    192.168.0.3 3ffe:8010:18::1000:3

-v  Be verbose and don't detach.

-V  Print version and exit.

NOTES
Option -H to disable all resolver hints has been removed since proper combination of -4 and -6 will yield in any combination of IPv4 and IPv6 sources and destinations.

SIGNALS
Sending SIGHUP forces map file reload.

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@toxygen.net), Dariusz Jackowski (ascent@linux.pl), Ramunas Lukosevicus (lukoramu@parok.lt), Roland Stigge (stigge@antcom.de)

SEE ALSO
ssh(1)