Re: [Trans] [trans] #74 (rfc6962-bis): normative statement of TLS client behavior in Section 3

Stephen Kent <kent@bbn.com> Mon, 06 July 2015 14:50 UTC

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Date: Mon, 06 Jul 2015 10:50:47 -0400
From: Stephen Kent <kent@bbn.com>
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Subject: Re: [Trans] [trans] #74 (rfc6962-bis): normative statement of TLS client behavior in Section 3
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I note the following text from the -07 draft that appear to specify TLS 
client behavior:

Section 1

    TLS clients can thus require that all certificates they accept as 
valid have been logged.

Section 3

    A certificate not
    accompanied by an SCT (either for the end-entity certificate or for a
    name-constrained intermediate the end-entity certificate chains to)
    MUST NOT be considered compliant by TLS clients.


Section 3.4

    TLS clients MUST implement all three mechanisms.


Section 3.4.1

    TLS clients that support the extension SHOULD send a ClientHello
    extension with the appropriate type and empty "extension_data".

    TLS clients
    SHOULD include the extension type in the ClientHello, but if the
    session is resumed, the TLS server is not expected to process it or
    include the extension in the ServerHello.


Section 5.3


    In addition to normal validation of the certificate and its chain, 
*TLS**
**   clients SHOULD validate* the SCT by computing the signature input from
    the SCT data as well as the certificate and verifying the signature,
    using the corresponding log's public key.


> #74: normative statement of TLS client behavior in Section 3
>
>
> Comment (by benl@google.com):
>
>   Describing how the protocol works from the client's POV is _not_ about
>   client behaviour, it is about the client's understanding of the situation.
>   How it behaves as a result of that understanding is behaviour.
>
>   I propose this should be closed "wontfix".
>