Description of problem: OpenVPN compile-time feature request

Version-Release number of selected component (if applicable): 2.3.2


How reproducible:


Steps to Reproduce:
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Actual results:


Expected results:


Additional info:

HP issues X.509 certificates to employees called "DigitalBadges"
which are signed by an HP internal CA.  As an example, the subject
of an HP cert is similar to the following:

> Subject: O=Hewlett-Packard, OU=Employee,
> CN=John Doe/emailAddr=john.doe

Up to now, we have been authenticating using the CN field.
However, this field is not guaranteed to be unique within
HP's Enterprise Directory, e.g., there are six people with
"John Smith" and four with "Eric Wu".  The "emailAddr"
field is unique across HP, however.

I noticed that openvpn version 2.3 came out with a new option
called "--x509-username-field" that must be explicitly enabled
at compile time using the "--enable-x509-alt-username" option.
Currently, the EPEL6 openvpn package does not have this feature
enabled.  Could you please consider enabling it?  This would
help security by preventing authentication sharing among people
with the same Common Name attribute.

The Debian openvpn package has the same issue.  I communicated
with its maintainer, Alberto Gonzalez Iniesta, and he agreed
that the "--x509-username-field" option will be available in
the Debian binary packages as soon as the upstream developers
sign off on a small patch related to this feature.  It would be
great for users of Redhat/Fedora to also have access to this
feature.  Thanks.