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Re: [TLS] Call for acceptance of draft-moeller-tls-downgrade-scsv

Adam Langley <agl@google.com> Thu, 23 January 2014 20:43 UTC

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From: Adam Langley <agl@google.com>
Date: Thu, 23 Jan 2014 15:43:28 -0500
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To: Rob Stradling <rob.stradling@comodo.com>
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Subject: Re: [TLS] Call for acceptance of draft-moeller-tls-downgrade-scsv
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> I guess the chances of a server actually having TLS_NULL_WITH_NULL_NULL
> enabled and choosing to select it above all other mutually supported ciphers
> is pretty remote.  But nonetheless, is there any reason why
> TLS_FALLBACK_SCSV couldn't have a value of, say, {0x00, 0xFE} ?

Has anything ever implemented TLS_NULL_WITH_NULL_NULL?

Either way, it's not a big problem to change the SCSV value if need
be, although I don't believe that servers mistaking it for
TLS_NULL_WITH_NULL_NULL will be an issue. Additionally, the value is
added at the end of the list in practice.


Cheers

AGL

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