What makes a certificate invalid?

Shanishchara, Kunal Kunal.Shanishchara at spirent.com
Fri Dec 11 22:01:32 CET 2009

Thanks for your query Rupert.

The problem we are trying to solve is to test the behavior when a
failure happens. Sorry for not making this clear in my earlier email. 



-----Original Message-----
From: Rupert Kittinger-Sereinig [mailto:rks at mur.at] 
Sent: Friday, December 11, 2009 3:58 PM
To: Shanishchara, Kunal
Subject: Re: What makes a certificate invalid?

I do not understand the problem you want to solve. Why do you want the
handshake to fail?

If you want to use this as a way for the client to choose between
several certificates, I do not think this is necessary. The client
certificate request already includes a list of Distinguished Names that
are acceptable Certificate Authorities.


Shanishchara, Kunal schrieb:
> Hi Daniel,
> Thank you for the detailed answers (previous email) and pointing to 
> the link. These are very helpful.
> I must admit though that I am still unable to comprehend the right 
> behavior for the particular scenario that I have in mind.
> I am going to describe it to the best of my ability. Please find the 
> description below.
> Problem Description:
> I have generated my own root certificate, lets say xyz.cer. I use this

> root certificate to generate certificates for 2 different FQDNs, lets 
> say abc.com and def.org.
> Now, I am trying to induce an authentication failure by doing the 
> following.
> 1. The server sends the certificate generated for def.org and the 
> client sends a certificate for abc.com. Both these certificates were 
> generated using same X.509  certificate xyz.cer.
> 2. The server expects the client to fail the TLS authentication during

> server hello, client hello messaging.
> 3. Based on the authentication failure, client will fallback to 
> def.org (as per the higher layer specification) and the successive 
> attempt will go through.
> Questions:
> Is the Server correct in expecting an authentication failure in Step
> If no, apart from providing invalid certificate with some obvious 
> cause (expired cert, etc..) is there another way to implement the 
> functionality on the server?
> Thanks in advance. 
> Thanks and regards,
> Kunal.
Rupert Kittinger-Sereinig <rks at mur.at>
Krenngasse 32
A-8010 Graz

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