tool for tunneling IPv4 data through a DNS server

 This is a piece of software that lets you tunnel IPv4 data through a DNS
 server. This can be usable in different situations where internet access is
 firewalled, but DNS queries are allowed.
 .
 iodine is similar to nstx but has password authentication, brings up the
 tun interface automatically and lets the user specify the IP address as a
 command line option.