Note

Dns2tcp is a tool for relaying TCP connections over DNS. There is only a simple identification mecanism but no encryption : DNS encapsulation must be considered as an unsecure and anonymous transport layer. Resources should be public external services like ssh, ssltunnel ...

Examples

Client:

View list of available connection.

    $ dns2tcpc -z dns2tcp.hsc.fr -k <my-key>  <dns_server>
    Available connection(s) :
            ssh-gw
            ssh6-home
            ssl-tunnel
    $

Line based connection to a remote ssl-tunnel host :

    $ dns2tcpc -r ssl-tunnel -l 4430 -k <my-key> -z dns2tcp._hsc.fr <dns_server>
    listening on port 4430
    ...

File configuration :

    $ cat > ~/.dns2tcprc << EOF

    domain = dns2tcp.hsc.fr
    resource = ssl-tunnel
    local_port = 4430
    debug_level = 1
    key = whateveryouwant
    server = the_dns_server # or scan /etc/resolv.conf
    EOF
    $ dns2tcpc

Server :

File configuration :

    $ cat > ~/.dns2tcpdrc << EOF

    listen = x.x.x.x
    port = 53
    user = nobody
    key = whateveryouwant
    chroot = /var/empty/dns2tcp/
    domain = dns2tcp.hsc.fr
    resources = ssh:127.0.0.1:22 ,          smtp:127.0.0.1:25,
                    pop3:10.0.0.1:110, ssh2:[fe80::1664]:22

    EOF
    $ ./dns2tcpd -F -d 1

Known Bugs

DNS desynchronisation dns2tcpd server not supported on Windows