NAME

Authen::Libwrap - access to Wietse Venema's TCP Wrappers library

SYNOPSIS

  use Authen::Libwrap qw( hosts_ctl STRING_UNKNOWN );

  # we know the remote username (using identd)
  $rc = hosts_ctl(      "programname",
                        "hostname.domain.com",
                        "10.1.1.1",
                        "username" );
  );
  print "Access is ", $rc ? "granted" : "refused", "\n";

  # we don't know the remote username
  $rc = hosts_ctl(      "programname",
                        "hostname.domain.com",
                        "10.1.1.1",
                        STRING_UNKNOWN );
  );
  print "Access is ", $rc ? "granted" : "refused", "\n";

DESCRIPTION

The Authen::Libwrap module allows you to access the hosts_ctl() function from the popular TCP Wrappers security package. This allows validation of network access from perl programs against the system-wide hosts.allow file.

If any of the parameters to hosts_ctl() are not known (i.e. username due to lack of an identd server), the constant STRING_UNKNOWN should be passed to the function.

EXPORTS

  Nothing unless you ask for it.

  hosts_ctl( $daemon, $hostname, $ip_address, $username );

CONSTANTS

  STRING_UNKNOWN

BUGS

Calls to hosts_ctl() which a line in hosts.allow that uses the "twist" option will terminate the running perl program. This is not a bug in Authen::Libwrap per se -- libwrap uses exec(3) to replace the running process with the specified program, so there's nothing to return to.

Some operating systems ship with a default catch-all rule in hosts.allow that uses the twist option. You may have to modify this configuration to use Authen::Libwrap effectively.

AUTHOR

James FitzGibbon, <james@ehlo.com>

SEE ALSO

perl(1), hosts_access(3), hosts_access(5), hosts_options(5)