Re: [TLS] Transcript-Hash during Handshake
Peter Wu <peter@lekensteyn.nl> Wed, 22 November 2017 03:59 UTC
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Date: Wed, 22 Nov 2017 03:59:15 +0000
From: Peter Wu <peter@lekensteyn.nl>
To: "Le Van Gong, Hubert" <hubert@levangong.org>
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Subject: Re: [TLS] Transcript-Hash during Handshake
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Hi Hubert, On Tue, Nov 21, 2017 at 07:38:16PM -0800, Le Van Gong, Hubert wrote: > Greetings, > > Probably a trivial question but is the transcript hash (during handhsake) > calculated over decrypted versions of messages like EncryptedExtensions or > certificate or is it done over the raw/encrypted messages? > I could not find an exact confirmation in the spec. It covers the decrypted handshake messages, see https://tools.ietf.org/html/draft-ietf-tls-tls13-21#section-4.4.1 This value is computed by hashing the concatenation of each included handshake message, including the handshake message header carrying the handshake message type and length fields, but not including record layer headers (The only way to know the message type is to have it in cleartext.) -- Kind regards, Peter Wu https://lekensteyn.nl
- [TLS] Transcript-Hash during Handshake Le Van Gong, Hubert
- Re: [TLS] Transcript-Hash during Handshake Peter Wu
- Re: [TLS] Transcript-Hash during Handshake Le Van Gong, Hubert
- Re: [TLS] Transcript-Hash during Handshake Andrei Popov
- Re: [TLS] Transcript-Hash during Handshake Ilari Liusvaara
- Re: [TLS] Transcript-Hash during Handshake Andrei Popov