[TLS] Labels in HKDF-Expand-Label
Martin Thomson <martin.thomson@gmail.com> Wed, 23 November 2016 05:25 UTC
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From: Martin Thomson <martin.thomson@gmail.com>
Date: Wed, 23 Nov 2016 16:25:47 +1100
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Subject: [TLS] Labels in HKDF-Expand-Label
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The grammar for the label permits the label to be 9 octets long. That's the exact length of the prefix. That means that it is valid to use an exporter with an empty label string. That seems dangerous. I propose that we require at least one octet: https://github.com/tlswg/tls13-spec/pull/774
- [TLS] Labels in HKDF-Expand-Label Martin Thomson
- Re: [TLS] Labels in HKDF-Expand-Label Eric Rescorla