[TLS] Explicit curve parameters in Server Key Exchange messages

Juraj Somorovsky <juraj.somorovsky@rub.de> Fri, 17 January 2020 13:08 UTC

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To: "tls@ietf.org" <tls@ietf.org>
Cc: Robert Merget <Robert.Merget@ruhr-uni-bochum.de>, Nimrod Aviram <nimrod.aviram@gmail.com>
From: Juraj Somorovsky <juraj.somorovsky@rub.de>
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Subject: [TLS] Explicit curve parameters in Server Key Exchange messages
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Dear all,

related to the recent Windows/NSA custom curve certificate issues, we
are wondering whether there are any implementations also supporting
explicit curves in TLS server key exchange messages as defined in
https://tools.ietf.org/html/rfc4492#section-5.4

Typical TLS implementations we are aware of only support named curves in
server key exchange messages.

Note that this is different from the custom curves in X.509
certificates. According to RFC4492, it is also possible to use custom
explicit curves directly in the TLS protocol.

Thank you

-- 
Dr.-Ing. Juraj Somorovsky

Lehrstuhl für Netz- und Datensicherheit
Ruhr Universität Bochum
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