[NNTP] One more STARTTLS issue

[Ken Murchison]

Russ Allbery wrote:

> Ken Murchison <ken at oceana.com> writes:
> 
>>Russ Allbery wrote:
> 
> 
>>>Sorry, I missed this.
> 
> 
>>>I don't think we did anything about this portion of Sam's review of
>>>STARTTLS:
> 
> 
>>>| The TLS document discusses certificate matching but does not discuss
>>>| certificate verification.  I'd recommend using the certificate
>>>| verification specified in RFC 3280.  You certainly need to say
>>>| something about verification.
> 
> 
>>>I think this may be as simple as inserting a sentence or so with a
>>>normative reference to RFC 3280.
> 
> 
>>Suggested wording?  Is this a SHOULD or a MUST?
> 
> 
> How does this sound:
> 
>     To prevent man-in-the-middle attacks, clients MUST verify the binding
>     between the identity of the server to which the client was connecting
>     and the public key presented by the server.  Clients SHOULD implement
>     the algorithm in section 6 of [RFC3280] for general certificate
>     validation, but MAY supplement that algorithm with other validation
>     methods that achieve equivalent levels of verification (such as
>     comparing the server certificate against a local store of
>     already-verified certificates and identity bindings).

Sounds good to me.  Do you want to run it by Sam?  Should I spin another 
draft after we add this (or equivalent) wording?

-- 
Kenneth Murchison     Oceana Matrix Ltd.
Software Engineer     2495 Main St. - Suite 401
716-604-0088 x26      Buffalo, NY 14214
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