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Re: [MMUSIC] draft-dtls-sdp: Allow offerer to establish DTLS association before it has received the SDP answer?

Martin Thomson <martin.thomson@gmail.com> Fri, 26 May 2017 11:02 UTC

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From: Martin Thomson <martin.thomson@gmail.com>
Date: Fri, 26 May 2017 21:01:58 +1000
Message-ID: <CABkgnnXXCj55+f0pG0_5PeAB0GMi3m4EdgPUFFv2=-07uxb_Yw@mail.gmail.com>
To: Eric Rescorla <ekr@rtfm.com>
Cc: Christer Holmberg <christer.holmberg@ericsson.com>, "mmusic@ietf.org" <mmusic@ietf.org>
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Subject: Re: [MMUSIC] draft-dtls-sdp: Allow offerer to establish DTLS association before it has received the SDP answer?
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On 26 May 2017 at 20:37, Eric Rescorla <ekr@rtfm.com> wrote:
> Also, you say that if you initiate the handshake before the answer
> is received you are vulnerable to attacks. What attacks are those?

It should be "complete" - on the assumption that a completed handshake
leads immediately to using the connection.  Really, it's using the
connection (sending or receiving data or using exporters) that puts
you at risk, but I don't think that it's worth putting that fine a
distinction on it.

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