This program can be used in readers.conf to grant access based on the
subdomain part of the remote hostname. In particular, it only returns
success if the remote hostname ends in domainname. (A leading dot on
domainname is optional; even without it, the argument must match on
dot-separated boundaries). The ``username'' returned is whatever initial
part of the remote hostname remains after domainname is removed. It
is an error if there is no initial part (that is, if the remote hostname
is exactly the specified domainname).
The following readers.conf(5) fragment grants access to hosts with
internal domain names:
Access is granted to the example.* groups for all connections from hosts
that resolve to hostnames ending in ".internal"; a connection from
``foo.internal'' would match access groups as ``email@example.com''.
It seems the code does not confirm that the matching part is actually at
the end of the remote hostname (e.g., ``domain: example.com'' would match
the remote host ``foo.example.com.org'' by ignoring the trailing ``.org''
Does this resolver actually provide any useful functionality not
available by using wildcards in the readers.conf(5) hosts parameter?
If so, the example above should reflect this functionality.