libapache-ssllookup-perl binary package in Ubuntu Xenial amd64

 Apache::SSLLookup is a glue layer between Perl handlers and the mod_ssl
 public API. Under normal circumstances, you would use $r->subprocess_env() to
 glean information about mod_ssl. for example,
 .
 $request_is_over_ssl = $r->subprocess_env('HTTPS');
 .
 however, this is only possible after mod_ssl runs its fixups - that is, Perl
 handlers can only accurately check the subprocess_env table for mod_ssl
 information in the PerlResponsePhase or later.
 .
 This module allows you to query mod_ssl directly via its public C API at any
 point in the request cycle. but without using C, of course.

Source package