[openssl-users] Certificate template information

[Jakob Bohm]

(top posting because OP did so)

Note that as I already said, checking the template name
is usually a mistake, unless you happen to know that
some other software will reject certificates without
specific template names.

It is much more relevant (and should be done even if
the template name is also checked) to check all the
specific certificate properties (extensions, basic
settings, name forms etc.) against the requirements.

Tests such as:

Does it include the required set of key usages and
extended key usages?

Does it include any neither required nor optional
(and thus unwanted) key usages or extended key
usages?

Does the Subject Name have the required form and
the required fields?

Does it include any required "Subject Alternate
Names".

Does it include any unwanted "Subject Alternate
Names".

Is the key of the required type and size?

Is the signature on the certificate of the required
type and size?

Etc. Etc.

Basically, look at valid certificates and create a
test for each of the fields/attributes.

This way, unless some other broken software tests the
template name, the testing will be correct even if at
some later stage a "variant" template is created for
some subset of the certificates used for this purpose.
For example, a special template for servers in the HR
department.

On 28/04/2015 10:08, Franks Andy (IT Technical Architecture Manager) wrote:
> Thanks Rich, Jakob.
> So, can I use openssl as it is to query the values of the extension on an existing certificate do you think? The usual issue seems that people want to use openssl to form a request and insert the ms CA template name in there otherwise it complains. I don't want to do that, I want to take a presented certificate (to freeradius) and perform something in the shell that will check  against acceptable template names (and that the certificate chains properly, but that's not a problem).
> I can't find anything on google citing that someone has achieved it so far.
> Thanks again.
> Andy
>
> -----Original Message-----
> From: openssl-users [mailto:openssl-users-bounces at openssl.org] On Behalf Of Jakob Bohm
> Sent: 28 April 2015 04:17
> To: openssl-users at openssl.org
> Subject: Re: [openssl-users] Certificate template information
>
> On 28/04/2015 02:59, Salz, Rich wrote:
>>> I have need to identify a Microsoft generated certificate's template name, I believe as part of oid 1.3.6.1.4.1.311.21.7
>> Where, in a cert OtherName field?
> It is an extension.  Microsoft certificate server (their
> bundled CA software) puts the name of the "certificate
> template" (analogous to an openssl.cnf section) in a
> certificate extension, and a few other Microsoft tools
> unfortunately check this name in addition to more
> relevant conditions such as EKU values etc.
>
> The form I know of can be implemented as follows in
> openssl.cnf (in the [sometemplatename_cert] section of
> the file):
>
> #     enrollCerttypeExtension (1 3 6 1 4 1 311 20 2)
> #   OCTET STRING, encapsulates {
> #     BMPString 'SomeTemplateName'
> #     }
> #   }
> 1.3.6.1.4.1.311.20.2 = ASN1:BMP:SomeTemplateName
>
> I am not sure about the 1.3.6.1.4.1.311.21.7 OID, but it
> might be similar.
>
> Enjoy
>
> Jakob


Enjoy

Jakob
-- 
Jakob Bohm, CIO, Partner, WiseMo A/S.  http://www.wisemo.com
Transformervej 29, 2860 Søborg, Denmark.  Direct +45 31 13 16 10
This public discussion message is non-binding and may contain errors.
WiseMo - Remote Service Management for PCs, Phones and Embedded

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mta.openssl.org/pipermail/openssl-users/attachments/20150428/f9094607/attachment-0001.html>