Ubuntu Manpage: tnat64.conf - configuration file for tnat64(8)

NAME

       tnat64.conf - configuration file for tnat64(8)

OVERVIEW

The configuration for tnat64 can be anything from two lines to hundreds of lines based on
the needs at any particular site. The basic idea is to define any networks the machine can
access directly via IPv4 and define one or many NAT64 prefixes to be used to access other
networks (including a 'default' prefix).

Local networks are declared using the 'local' keyword in the configuration file. When
applications attempt to connect to machines in networks marked as local tnat64 will not
attempt to use a NAT64 prefix.

Obviously if a connection is not to a locally accessible network it will need to be
proxied over a NAT64. However, sometimes you may need to use different NAT64 prefixes to
access different internal (and external) networks. For this reason the configuration file
allows the definition of 'paths' as well as a default NAT64 prefix.

Paths are declared as blocks in the configuration file. That is, they begin with a 'path
{' line in the configuration file and end with a '}' line. Inside this block directives
should be used to declare a NAT64 proxy (as documented later in this manual page) and
'subnet' directives should be used to declare networks and even destination ports in those
networks that this server should be used to reach. Please note that each path MUST define
a NAT64 prefix and contain one or more 'subnet' directives.

NAT64 prefix declaration directives that are not contained within a 'path' block define
the default NAT64 prefix. If tnat64 needs to connect to a machine via a NAT64 (i.e it
isn't a network declared as 'local') and no 'path' has declared it can reach that network
via a 'subnet' directive, this NAT64 prefix is used to construct IPv6 addresses.

CONFIGURATION SYNTAX

       The basic structure of all lines in the configuration file is:

              <directive> = <parameters>

       The exception to this is 'path' blocks which look like:

              path {
                     <directive> = <parameters>
              }

       Empty lines are ignored and all input on a line after a '#' character is ignored.

   DIRECTIVES
       The following directives are used in the tnat64 configuration file:

       nat64_prefix
              The prefix of IPv6 address of the NAT64 (e.g. "nat64_prefix = 64:ff9b::"). Only one
              NAT64 prefix may be specified per path block, or  one  outside  a  path  block  (to
              define the default NAT64 prefix). The NAT64 prefix is always /96.

       local  An  IP/subnet  pair  specifying  a  network  which may be accessed directly without
              proxying through NAT64 (e.g "local = 10.0.0.0/255.0.0.0").

       subnet This directive is only valid inside a  path  block.  Its  parameter  is  formed  as
              IP[:startport[-endport]]/subnet and it specifies a network (and a range of ports on
              that network) that can be accessed by through NAT64 specified in this  path  block.
              For  example,  in  a path block "subnet = 150.0.0.0:80-1024/255.0.0.0" indicates to
              tnat64 that the NAT64 prefix specified in the current path block should be used  to
              access  any  IPs  in  the  range  150.0.0.0  to 150.255.255.255 when the connection
              request is for ports 80-1024.

UTILITIES

       tnat64 comes with two utilities that can be useful in creating and  verifying  the  tnat64
       configuration file.

       tnat64-validateconf
              tnat64-validateconf  can  be  used  to verify the configuration file. It checks the
              format of the file and also the contents for errors. Having read the file it  dumps
              the  configuration  to  the  screen  in  a  formatted, readable manner. This can be
              extremely useful in debugging problems.

              tnat64-validateconf can read a configuration file from a location  other  than  the
              location specified at compile time with the -f <filename> command line option.

              Normally  tnat64-validateconf simply dumps the configuration read to the screen (in
              a nicely readable format), however it also has a useful 'test' mode. When passed  a
              hostname/ip   on  the  command  line  like  -t  <hostname/ip>,  tnat64-validateconf
              determines which of the NAT64 prefixes specified in the configuration file would be
              used by tnat64 to access the specified host.

AUTHORS

       Andrej Shadura (andrew@shadura.me), Shaun Clowes (delius@progsoc.uts.edu.au)

COPYRIGHT