Date: Sun, 3 Jun 2018 12:48:36 +0200
From: Gert Doering <gert@...1296...>
Message-ID: <20180603104836.GN79551@...1296...>
References: <1528020718-12721-1-git-send-email-steffan@...1856...>
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Subject: Re: [Openvpn-devel] [PATCH 2/3] Reject unadvertised compression
 algorithms
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To: Steffan Karger <steffan@...1856...>
Cc: openvpn-devel@lists.sourceforge.net

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Hi,

On Sun, Jun 03, 2018 at 12:11:57PM +0200, Steffan Karger wrote:
> A server should not push us compression algorithms we didn't specify.  If
> the server does so anyway, reject the compression algorithm.

I can see why you do this, but if I understand this right, this will
break lots of currently-working OpenVPN setups - where we use the IV_
variables to parse out "what can the client do?" and send matching
"compress <foo>" PUSH_REPLYs.

So, feature-NAK.

Adding warnings (1/3) and a warning-override (3/3) is good measure, but
interfering with server-to-client pushing of options needs more=20
consideration.

gert
--=20
"If was one thing all people took for granted, was conviction that if you=20
 feed honest figures into a computer, honest figures come out. Never doubte=
d=20
 it myself till I met a computer with a sense of humor."
                             Robert A. Heinlein, The Moon is a Harsh Mistre=
ss

Gert Doering - Munich, Germany                             gert@...1296...

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