Re: [TLS] rfc4366-bis: Certificate Status for intermediate CA

Martin Rex <> Tue, 29 September 2009 00:58 UTC

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From: Martin Rex <>
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To: (Yngve N. Pettersen)
Date: Tue, 29 Sep 2009 02:59:23 +0200 (MEST)
In-Reply-To: <> from "Yngve N. Pettersen" at Sep 28, 9 11:59:10 pm
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Subject: Re: [TLS] rfc4366-bis: Certificate Status for intermediate CA
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Yngve N. Pettersen wrote:
> However, sending two CertificateStatusRequest extensions in the same  
> ClientHello is forbidden by RFC 5246 sec
>     When multiple extensions of different types are present in the
>     ClientHello or ServerHello messages, the extensions MAY appear in any
>     order.  There MUST NOT be more than one extension of the same type.

How about always using the existing extension for the OCSP response
for the server certificate, and using a new extension for OCSP responses
for other certificates (like intermediate CA certs), probably unsorted.

PKIs with flat hierarchies (Server-cert signed by self-signed CA cert)
use only the original extension.  Servers with certs from multi-level
CA hierarchies need to use the new extension if they want to send
additional OCSP responses.