Re: [TLS] Interop failure due to wrong encoding of ServerDHParams
Hanno Böck <hanno@hboeck.de> Tue, 07 April 2015 12:31 UTC
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Date: Tue, 07 Apr 2015 14:31:48 +0200
From: Hanno Böck <hanno@hboeck.de>
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Subject: Re: [TLS] Interop failure due to wrong encoding of ServerDHParams
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On Tue, 07 Apr 2015 14:04:37 +0200 Florian Weimer <fweimer@redhat.com> wrote: > I've encountered a TLS 1.2 server implementation which sometimes > sends a ServerDHParams structure as part of the ServerKeyExchange > message which indicates a length of 127 bytes for the dh_Ys > parameter, but the parameter actually sent contains 128 bytes. As a > result, parsing the ServerKeyExchange message fails, leading to a > handshake failure. (Maybe this happens if the most significant byte > of dh_Ys is zero.) Hannes from ocaml-tls said something very similar a few days ago in a talk at CCC Berlin. But I think he also said he observed something like that on their servers, but doesn't know which implementation caused it. The talk was streamed and recorded, but I think it's not online yet. -- Hanno Böck http://hboeck.de/ mail/jabber: hanno@hboeck.de GPG: BBB51E42
- [TLS] Interop failure due to wrong encoding of Se… Florian Weimer
- Re: [TLS] Interop failure due to wrong encoding o… Hanno Böck
- Re: [TLS] Interop failure due to wrong encoding o… Hannes Mehnert