Re: [TLS] TLS Proxy Server Extension

Yoav Nir <> Tue, 26 July 2011 21:41 UTC

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From: Yoav Nir <>
To: Adam Langley <>
Date: Wed, 27 Jul 2011 00:41:28 +0300
Thread-Topic: [TLS] TLS Proxy Server Extension
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Cc: Philip Gladstone <>, David McGrew <>, "" <>
Subject: Re: [TLS] TLS Proxy Server Extension
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On Jul 26, 2011, at 5:25 PM, Adam Langley wrote:

> On Tue, Jul 26, 2011 at 5:17 PM, Yoav Nir <> wrote:
>> I don't know if you're following the LockFoo discussion on WebSec, but all of those locks would cause a hard-fail for clients connecting to sites that have specified them. As security people we might think "good!", but that would actually be a bar to implementations of LockFoo more than it would be a bar to deployment of TLS proxies. Giving the client access to the original certificates would allow the browser to overcome this limitation.
> At least in Chrome, user installed root CAs can override certificate
> pins. Thus MITM proxies aren't broken and nor will they be by any of
> the various pinning proposals in websec.

Really?  I thought Chrome used the operating system TA store. How can it tell the difference between a trust anchor that was installed by Microsoft and one that was installed by the user?

But I know that the EV indication goes away behind a proxy, and there's no way to make your CA certificate "EV" to the browser. Dave's proposal allows the green label to come back.