Re: [TLS] Antw: Re: Antw: Re: Suspicious behaviour of TLS server implementations
Viktor Dukhovni <ietf-dane@dukhovni.org> Thu, 22 September 2016 14:54 UTC
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From: Viktor Dukhovni <ietf-dane@dukhovni.org>
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Date: Thu, 22 Sep 2016 10:47:42 -0400
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Subject: Re: [TLS] Antw: Re: Antw: Re: Suspicious behaviour of TLS server implementations
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> On Sep 22, 2016, at 8:18 AM, Andreas Walz <andreas.walz@hs-offenburg.de> wrote: > > I see your point here. However, where would you draw the line between "I can't" and "I don't want to"? Think of a cipher suites list with 3 bytes in a ClientHello. You can still find one cipher suite that could be ok to work with. However, how can you trust the first two bytes if you find that third byte telling you something's abnormal? The server tries that first cipher, if mutually supported, and if it works, it guessed right. If the finished message from the server is valid, the client's handshake as seen by the server was presumably exactly what the client sent, so the client gets what it paid for... Servers don't have to be that forgiving, but it is a plausible approach. -- Viktor.
- [TLS] Suspicious behaviour of TLS server implemen… Andreas Walz
- Re: [TLS] Suspicious behaviour of TLS server impl… Martin Rex
- Re: [TLS] Suspicious behaviour of TLS server impl… Martin Thomson
- [TLS] Antw: Re: Suspicious behaviour of TLS serve… Andreas Walz
- Re: [TLS] Suspicious behaviour of TLS server impl… Hubert Kario
- Re: [TLS] Suspicious behaviour of TLS server impl… Peter Gutmann
- Re: [TLS] Suspicious behaviour of TLS server impl… Andreas Walz
- Re: [TLS] Suspicious behaviour of TLS server impl… Hubert Kario
- Re: [TLS] Suspicious behaviour of TLS server impl… Andreas Walz
- Re: [TLS] Suspicious behaviour of TLS server impl… Martin Thomson
- Re: [TLS] Suspicious behaviour of TLS server impl… Andreas Walz
- Re: [TLS] Suspicious behaviour of TLS server impl… Hubert Kario
- Re: [TLS] Suspicious behaviour of TLS server impl… Peter Gutmann
- Re: [TLS] Suspicious behaviour of TLS server impl… Ilari Liusvaara
- [TLS] Antw: Re: Suspicious behaviour of TLS serve… Andreas Walz
- Re: [TLS] Suspicious behaviour of TLS server impl… Martin Thomson
- Re: [TLS] Antw: Re: Suspicious behaviour of TLS s… Peter Gutmann
- Re: [TLS] Suspicious behaviour of TLS server impl… Peter Gutmann
- Re: [TLS] Suspicious behaviour of TLS server impl… Yoav Nir
- Re: [TLS] Suspicious behaviour of TLS server impl… Ilari Liusvaara
- Re: [TLS] Suspicious behaviour of TLS server impl… Hubert Kario
- [TLS] Antw: Re: Antw: Re: Suspicious behaviour of… Andreas Walz
- Re: [TLS] Antw: Re: Antw: Re: Suspicious behaviou… Viktor Dukhovni
- Re: [TLS] Antw: Re: Antw: Re: Suspicious behaviou… Martin Thomson
- Re: [TLS] Suspicious behaviour of TLS server impl… Peter Gutmann
- Re: [TLS] Suspicious behaviour of TLS server impl… Peter Gutmann
- Re: [TLS] Antw: Re: Antw: Re: Suspicious behaviou… Peter Gutmann
- Re: [TLS] Antw: Re: Antw: Re: Suspicious behaviou… Hubert Kario
- Re: [TLS] Antw: Re: Antw: Re: Suspicious behaviou… Christian Huitema
- Re: [TLS] Antw: Re: Antw: Re: Suspicious behaviou… Andrei Popov