[TLS] [removing renegotiation patch 1/2] clarify when no_renegotiation alert is fatal

Daniel Kahn Gillmor <dkg@fifthhorseman.net> Sun, 09 November 2014 07:01 UTC

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From: Daniel Kahn Gillmor <dkg@fifthhorseman.net>
To: tls@ietf.org
Date: Sat, 08 Nov 2014 14:29:30 -0500
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Subject: [TLS] [removing renegotiation patch 1/2] clarify when no_renegotiation alert is fatal
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In 1.2 and earlier, the no_renegotiation alert is "always a warning".

Under the current proposal, in TLS 1.3 it is "always fatal".

I (think i) understand the scope of these statements, but i worry that
"always" can be interpreted more broadly than intended.
 draft-ietf-tls-tls13.md | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/draft-ietf-tls-tls13.md b/draft-ietf-tls-tls13.md
index 729fa3a..14ec39a 100644
--- a/draft-ietf-tls-tls13.md
+++ b/draft-ietf-tls-tls13.md
@@ -1435,8 +1435,8 @@ no_renegotiation
 : Sent by the client in response to a hello request or by the server
   in response to a client hello after initial handshaking. Versions
   of TLS prior to TLS 1.3 supported renegotiation of a previously
-  established connection; TLS 1.3 removes this feature. This
-  message is always fatal.
+  established connection; TLS 1.3 removes this feature. When the
+  protocol version is TLS 1.3, this message is a fatal alert.
 : sent by clients that receive an extended server hello containing