IETF Logo Mail Archive

Re: [saag] Best practices for verifying authenticity of OpenPGP keys?

Simon Josefsson <simon@josefsson.org> Thu, 15 April 2021 10:18 UTC

Return-Path: <simon@josefsson.org>
X-Original-To: saag@ietfa.amsl.com
Delivered-To: saag@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id C84153A19BC for <saag@ietfa.amsl.com>; Thu, 15 Apr 2021 03:18:21 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.1
X-Spam-Level:
X-Spam-Status: No, score=-2.1 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_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=neutral reason="invalid (unsupported algorithm ed25519-sha256)" header.d=josefsson.org header.b=SLxtVLJK; dkim=pass (2736-bit key) header.d=josefsson.org header.b=Yq5YmO9Z
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 nZPY1Vll7MyY for <saag@ietfa.amsl.com>; Thu, 15 Apr 2021 03:18:16 -0700 (PDT)
Received: from uggla.sjd.se (uggla.sjd.se [IPv6:2001:9b1:8633::107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id C4BE03A19B7 for <saag@ietf.org>; Thu, 15 Apr 2021 03:18:14 -0700 (PDT)
DKIM-Signature: v=1; a=ed25519-sha256; q=dns/txt; c=relaxed/relaxed; d=josefsson.org; s=ed2101; h=Content-Type:MIME-Version:Message-ID:In-Reply-To :Date:References:Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding :Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=miEDslKc2Hqh+WPXNZvU4/c68Vw1RSnwTls/252brck=; t=1618481895; x=1619691495; b=SLxtVLJKU5WbEyiXsVnq+qggi95+rA1VOIy0C+L0LMO8NYzBBla1wf6oCCizdU+4yLHIvefY8T bLrp9Y6/eyBg==;
DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=josefsson.org; s=rsa2101; h=Content-Type:MIME-Version:Message-ID: In-Reply-To:Date:References:Subject:Cc:To:From:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=miEDslKc2Hqh+WPXNZvU4/c68Vw1RSnwTls/252brck=; t=1618481895; x=1619691495; b=Yq5YmO9Z139QBdkg7E8I29ZNfpv9ooMW51RtOpYFUYKHKDQ+i3It0WRMYRWGiAShqrgbrM/XHX 8j8q/Hv4btsFGpPsyFYKEaoxHGaGrEIAdPkWDvMDoy+tP6DlYvr57FozGyN5+ZJP6AUCumrYPbYL0 D8Z7v9Q8lWHQhawyttk4NCn/2HaNzOFl8fMZyYqIzPn8+7TcLINg33FbizG0FvjnJneAjx92j2kmj ZUW+MahFbe/OykpHJpH2fSjkAdZDKFU/FcJYLl9VkJBYG/KgA6zRGfZFRtQNlBIb+KFJY4Y2Phy8k +7HzA3dQQQL3WkaZn7Wl8cHzoOoy3yXU2v86//4c3Y4OXzfJho1k3AOwmHAtx/eDDDqHwXxGnYVKS QmcNgIFl4k0vBztq+WvGfaLrsjOxy8S+Rwtfq2mln08UezYSRqsVu1ZRZKcxDAa3/W4Rogl722 ;
Received: from [2001:9b1:41ac:ff00:c14a:d2e3:44b0:37b7] (port=58824 helo=latte) by uggla.sjd.se with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from <simon@josefsson.org>) id 1lWz4W-00018e-Tq; Thu, 15 Apr 2021 10:18:04 +0000
From: Simon Josefsson <simon@josefsson.org>
To: Yakov Shafranovich <yakov@nightwatchcybersecurity.com>
Cc: saag@ietf.org
References: <CAAyEnSNCTWL-qiKW=4bm6ySv1Suv7Vwwe3tnXDKSBBZFPAotZg@mail.gmail.com>
OpenPGP: id=B1D2BD1375BECB784CF4F8C4D73CF638C53C06BE; url=https://josefsson.org/key-20190320.txt
X-Hashcash: 1:22:210415:saag@ietf.org::dqPg8hK/90PEdN2W:HjQC
X-Hashcash: 1:22:210415:yakov@nightwatchcybersecurity.com::9ZFdw4UBp3k4IHpK:khFQ
Date: Thu, 15 Apr 2021 12:18:02 +0200
In-Reply-To: <CAAyEnSNCTWL-qiKW=4bm6ySv1Suv7Vwwe3tnXDKSBBZFPAotZg@mail.gmail.com> (Yakov Shafranovich's message of "Wed, 14 Apr 2021 22:32:47 -0400")
Message-ID: <87y2djq2at.fsf@latte.josefsson.org>
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux)
MIME-Version: 1.0
Content-Type: multipart/signed; boundary="=-=-="; micalg="pgp-sha256"; protocol="application/pgp-signature"
Archived-At: <https://mailarchive.ietf.org/arch/msg/saag/5AYIdaqPkUxgIJuOb2fzVk7MYOY>
Subject: Re: [saag] Best practices for verifying authenticity of OpenPGP keys?
X-BeenThere: saag@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Security Area Advisory Group <saag.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/saag>, <mailto:saag-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/saag/>
List-Post: <mailto:saag@ietf.org>
List-Help: <mailto:saag-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/saag>, <mailto:saag-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 15 Apr 2021 10:18:22 -0000

Yakov Shafranovich <yakov@nightwatchcybersecurity.com> writes:

> (this is another issue that was recently raised by an implementer of
> "security.txt")
>
> What is the current best practice for verifying whether a given
> OpenPGP key is real and valid? Not clear if Web of Trust is widely
> used anymore, PKI isn't applicable and public keyservers have been
> targeted in the past by poisoning attacks.
>
> To me, the most common approach seems to be publishing the keys or
> their fingerprints on the web where they can be retrieved with TLS,
> essentially relying on public PKI. This appears to be the approach
> used by OpenSSL, Tails, Tor, etc.

Indeed, see:
https://tools.ietf.org/html/draft-koch-openpgp-webkey-service-11

/Simon

> See:
> https://www.openssl.org/community/omc.html
> https://tails.boum.org/install/mac/usb-download/index.en.html
> https://support.torproject.org/tbb/how-to-verify-signature/
>
> Thanks
>

v2.23.0 | Report a Bug | By Email