Re: [TLS] which alert for TLS client cert w/o keyUsage digitalSignature

Rob Stradling <rob.stradling@comodo.com> Thu, 19 September 2013 21:19 UTC

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Date: Thu, 19 Sep 2013 22:18:55 +0100
From: Rob Stradling <rob.stradling@comodo.com>
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Subject: Re: [TLS] which alert for TLS client cert w/o keyUsage digitalSignature
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On 19/09/13 18:01, Michael D'Errico wrote:
>>> Wan-Teh Chang wrote:
>>>> Note: I don't understand why RFC 4492 says "It MUST be signed with
>>>> RSA."
<snip>
> Page 47 of RFC 5246 hints at these rules:
<snip>

RFC 5246 relaxes the "It MUST be signed with RSA" rule, doesn't it?

Appendix A.7 (Changes to RFC 4492) says:
   "As described in Sections 7.4.2 and 7.4.6, the restrictions on the
    signature algorithms used to sign certificates are no longer tied to
    the cipher suite (when used by the server) or the
    ClientCertificateType (when used by the client).  Thus, the
    restrictions on the algorithm used to sign certificates specified in
    Sections 2 and 3 of RFC 4492 are also relaxed."

-- 
Rob Stradling
Senior Research & Development Scientist
COMODO - Creating Trust Online