Re: [OAUTH-WG] DPoP - Downgrades, Transitional Rollout & Mixed Token Type Deployments

Torsten Lodderstedt <torsten@lodderstedt.net> Thu, 11 June 2020 17:51 UTC

Return-Path: <torsten@lodderstedt.net>
X-Original-To: oauth@ietfa.amsl.com
Delivered-To: oauth@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 58E4D3A0CB1 for <oauth@ietfa.amsl.com>; Thu, 11 Jun 2020 10:51:24 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.099
X-Spam-Level:
X-Spam-Status: No, score=-2.099 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=unavailable autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=lodderstedt.net
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id mUUE3_RzQmjm for <oauth@ietfa.amsl.com>; Thu, 11 Jun 2020 10:51:23 -0700 (PDT)
Received: from mail-wm1-x32f.google.com (mail-wm1-x32f.google.com [IPv6:2a00:1450:4864:20::32f]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id E30DB3A0CB2 for <oauth@ietf.org>; Thu, 11 Jun 2020 10:51:22 -0700 (PDT)
Received: by mail-wm1-x32f.google.com with SMTP id g10so5738859wmh.4 for <oauth@ietf.org>; Thu, 11 Jun 2020 10:51:22 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=lodderstedt.net; s=google; h=from:message-id:mime-version:subject:date:in-reply-to:cc:to :references; bh=AB8zFqddbkQJF7gE04FNUPK7mKCsiq121w8X2eXHZ3I=; b=gMo+wpaoMpvbazD0efo+pOivzJyFODunrM2Dw514nStoBpasGsMiGAN9NyBeX3slFA 7mRmg0cOQ9Lwg3xno3RNPTkYvS9X23tT1igFlkhYWKk4R9hxE3vTRpDhsc6ZQRnHAmd4 NgXQVO+r1n2TsF8OTTda2o8zsTdltqNDn/AuAwdxi9lHWSuszEf/c1TE1+XorChnLD31 BHPjQIdJWVZ7F5SrJVNZZEcd8yMp+qLipWsUhjLDE/TB3/JiHgX6GZW18kkkallSvyH6 4CSQrv0QatdTu2bqIG+Ow/itBQlAWcrlaGvMDrDXRfqWU1yF+6XFj1ZbEYguWBV3rcOd hYGA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:message-id:mime-version:subject:date :in-reply-to:cc:to:references; bh=AB8zFqddbkQJF7gE04FNUPK7mKCsiq121w8X2eXHZ3I=; b=gY9XxWV4XvUUetb8a/XO0WXYvjAYT38KvbJr3N8BpzDsjmDJm/Rvad3K1PfAgHAs/0 dJ0rsC0VOXQ5qQ+XZKThdJtm6i+FdYT3ZKIujWh2QarrZk4C+Y99NuGZRQJJdZX0FulY Hb2Cj1TsnfUU36KPjJPzNAOpd5CNhDyYOITm01D2gKM9Z8p9+ZSmH2UCpbxnVMuxPY9+ /c1P0o6ZEVmtF2ok1ytAiE0Byxxd/+QYef2RVikkxlVhqofi7wSm2OZmwiHngSAJEA1b 2yhqM0xkR6BfURQLOllUQ2akTgG+oFnWhrSaDnc/CEIh19tuO/zzOX9Bavki0C3TMnYe /sMg==
X-Gm-Message-State: AOAM531gqem9rzUYDfQoo/FUcbn5VwkGMN2U/MuDLMmOr9hoLxXbbl2d dGffr3+pq/f6JaPQCAetiEzmXkvM5Y8=
X-Google-Smtp-Source: ABdhPJy2L8xaHKkWX29twfA8bZAZSd8E0Ahk7wJREqg//rI5drJta4q9TopPkGvC1j7Of72wm0OWGQ==
X-Received: by 2002:a1c:5a82:: with SMTP id o124mr9113241wmb.188.1591897879829; Thu, 11 Jun 2020 10:51:19 -0700 (PDT)
Received: from p200300eb8f184cdad587c99b0cde18fd.dip0.t-ipconnect.de (p200300eb8f184cdad587c99b0cde18fd.dip0.t-ipconnect.de. [2003:eb:8f18:4cda:d587:c99b:cde:18fd]) by smtp.gmail.com with ESMTPSA id k17sm6163198wrl.54.2020.06.11.10.51.18 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 11 Jun 2020 10:51:18 -0700 (PDT)
From: Torsten Lodderstedt <torsten@lodderstedt.net>
Message-Id: <25B48BEE-D460-4CD8-8432-19D383E5B8EE@lodderstedt.net>
Content-Type: multipart/signed; boundary="Apple-Mail=_D93FE8F3-78F0-412A-8F1D-0D6482AE2735"; protocol="application/pkcs7-signature"; micalg=sha-256
Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.80.23.2.2\))
Date: Thu, 11 Jun 2020 19:51:16 +0200
In-Reply-To: <CAOW4vyNS1g51vrUPHYyAmma9XjjcwXUyUJPLJ6Artm8MFuxxWw@mail.gmail.com>
Cc: Neil Madden <neil.madden@forgerock.com>, oauth <oauth@ietf.org>
To: Francis Pouatcha <fpo=40adorsys.de@dmarc.ietf.org>
References: <8762DAF0-CA56-407D-9DD9-86809BD844B2@lodderstedt.net> <6473D5F3-7C90-400D-9263-FA5B6082496B@forgerock.com> <CAOW4vyNS1g51vrUPHYyAmma9XjjcwXUyUJPLJ6Artm8MFuxxWw@mail.gmail.com>
X-Mailer: Apple Mail (2.3608.80.23.2.2)
Archived-At: <https://mailarchive.ietf.org/arch/msg/oauth/aZp2bgS-CpjlNP5N7B_2KBYg0kQ>
Subject: Re: [OAUTH-WG] DPoP - Downgrades, Transitional Rollout & Mixed Token Type Deployments
X-BeenThere: oauth@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: OAUTH WG <oauth.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/oauth>, <mailto:oauth-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/oauth/>
List-Post: <mailto:oauth@ietf.org>
List-Help: <mailto:oauth-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/oauth>, <mailto:oauth-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 11 Jun 2020 17:51:24 -0000


> On 11. Jun 2020, at 19:24, Francis Pouatcha <fpo=40adorsys.de@dmarc.ietf.org> wrote:
> 
> 
> 
> On Thu, Jun 11, 2020 at 3:26 AM Neil Madden <neil.madden@forgerock.com> wrote:
> +1
> 
> > On 11 Jun 2020, at 07:36, Torsten Lodderstedt <torsten=40lodderstedt.net@dmarc.ietf.org> wrote:
> > 
> > I generally agree with the proposal, but I would suggest to limit it to public clients. 
>  
> > 
> > In case of confidential clients, the refresh token is (via the client_id) already bound to the client’s secret(s) and those can be rotated. Additionally binding the refresh token to a DPoP key would limit it’s applicability w/o a benefit. 
> I meant PoP and not DPoP. The client secret is also a variant of PoP. This does not change the value of this sentence: "refresh_token shall always be bound to a PoP".

This means you agree DPoP shall be used for refresh tokens issued to public clients only? As you said, client authentication is a kind of PoP as well, so confidential clients don’t need DPoP protection for refresh tokens. 

> 
> -- 
> Francis Pouatcha
> Co-Founder and Technical Lead at adorys
> https://adorsys-platform.de/solutions/