Re: [TLS] question about verification of client side certificate for TLS session for mutual authentication

Tony Arcieri <> Mon, 16 April 2018 18:38 UTC

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From: Tony Arcieri <>
Date: Mon, 16 Apr 2018 11:38:28 -0700
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Subject: Re: [TLS] question about verification of client side certificate for TLS session for mutual authentication
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On Mon, Apr 16, 2018 at 9:11 AM, Viktor Dukhovni <>

> A major obstacle to making access control decisions during the TLS
> handshake is that at that time the server often does not yet have enough
> information to determine which specific resource the client will ask to
> access.

There's also the problem that (at least in an SOA/"microservice
architecture") people will inevitably want some resources to be accessible
without a client certificate, e.g. status endpoints or anything consumed by
clients which do not support TLS certificates. In these cases it really
helps to force things up a level out of the TLS handshake into something at
the application level like an ACL language that lets you whitelist
unauthenticated access to these resources.

Tony Arcieri