Re: [TLS] Verifying X.509 Certificate Chains out of order

pgut001@cs.auckland.ac.nz (Peter Gutmann) Mon, 06 October 2008 09:44 UTC

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From: pgut001@cs.auckland.ac.nz (Peter Gutmann)
To: simon@josefsson.org, tls@ietf.org
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Date: Mon, 06 Oct 2008 22:44:49 +1300
Subject: Re: [TLS] Verifying X.509 Certificate Chains out of order
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Simon Josefsson <simon@josefsson.org>; writes:

>It is claimed that OpenSSL, IE and Firefox does not enforce the second
>MUST in the paragraph above, and succeeds in verifying an
>out-of-sequence chain.  I haven't verified the claim.  It appears as if
>the OpenSSL developers don't consider their behaviour as a bug (see
>reply below).

Add cryptlib to the list of implementations that don't care about the order. 
In fact I'd be kinda surprised if anyone (well, apart from GnuTLS) cared about 
cert order.

>What are others opinion on this?  I'm looking for some guidance on
>whether we should modify our current behaviour.

I'd say modify it, in fact I'm not sure what the rationale for requiring 
ordering was in the original spec, "it's tidier that way" doesn't strike me as 
a good argument :-).

Peter.
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