Re: [DNSOP] New Version Notification - draft-ietf-dnsop-svcb-https-06.txt

Dick Franks <rwfranks@gmail.com> Fri, 09 July 2021 07:01 UTC

Return-Path: <rwfranks@gmail.com>
X-Original-To: dnsop@ietfa.amsl.com
Delivered-To: dnsop@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id A7C753A14F2; Fri, 9 Jul 2021 00:01:21 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.098
X-Spam-Level:
X-Spam-Status: No, score=-2.098 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, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com
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 kHWtk-ZcZnCj; Fri, 9 Jul 2021 00:01:16 -0700 (PDT)
Received: from mail-io1-xd2c.google.com (mail-io1-xd2c.google.com [IPv6:2607:f8b0:4864:20::d2c]) (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 1747C3A0898; Fri, 9 Jul 2021 00:01:15 -0700 (PDT)
Received: by mail-io1-xd2c.google.com with SMTP id u7so11366707ion.3; Fri, 09 Jul 2021 00:01:15 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=Vz445Ju7zeLUKU1k7IsXT/WEqWfQXnpTdIc5Y8Oj/8c=; b=tCkO//m7q8lnmiMamgCQ7iCDK8ivTuDPZpcOuG1da+ceE9pfKypqn3TdZNr0S12Jtk i36AWOh8us0/Hni8xjSxDAVsOeHYzI+mjEDbi8hkCg2zb5U4Wzrp5w+90q0262I/2Rae lvNbtd0bbRKxKAvbAaz422T199xexnGeBscYbVNhiMYQrwr8pnRvyGviX0Q7AUOyq28M 7RFwolXq4iHfZ14NrNVL75jqhTJkaqQKNNsuCzUjENrigbENxD7ZOgBXLr8iPS/CODss o35MuUp9xMhZeGstE1k6i2Bi9gqrft3Jznx0cA05ne7GyFukpcNiSDx24h3g0gMCQej7 xvEw==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=Vz445Ju7zeLUKU1k7IsXT/WEqWfQXnpTdIc5Y8Oj/8c=; b=JEBE9iEYtVsv435iVF3LJhQSRi5PTosne0oMYJWuT4BAD6sk65kItWrWiQ3Vga7y0+ ISZTqYTjSB32/287JOzqggyhEV8rMUjAT0dUngNPGqPelq/2+jrQA70drNXj4+6ymxaX FLTKNyOPNeJ4iCixcNdSUMs+gks4ic6huJB9ifbdgEmDza/Qr5b0SNz1bqBueL2ES585 +R17k+V9/J1kOq48JD0Zog1DcQ1V8Ys1jgOt6x6wfDCdiGk59tmw1Q3rYjuIRsXm4uZI f4Gl74gWeTA6t6blYXcuHaPnWsBc7UNoRRXCbFLHByEHe3O7Mf8AP8nL5KZq588nyZgR ZsLQ==
X-Gm-Message-State: AOAM530rofBOuQwCE5vkSi8uZAWEmebdP6uOJsULInUgeDRcv5ghwC2f WYIqeBJFOH7IocM+ERF8gWhWEcVtepjoKSkPGS0=
X-Google-Smtp-Source: ABdhPJyGoboROgJ4MpkPTdaibSq3YuNz8ojfNVihPhH1I3GVu4iW+K1vJVnxS7fj+5n20IxnLO9ZBqSyc+HnuSkYjw0=
X-Received: by 2002:a02:a48d:: with SMTP id d13mr21813632jam.28.1625814074569; Fri, 09 Jul 2021 00:01:14 -0700 (PDT)
MIME-Version: 1.0
References: <162385376680.21187.3987569781956962248@ietfa.amsl.com> <CADyWQ+EuU4fe5WLAD7dRDhSfSgZfMWEk-jVW9z99x=cBKjd9uw@mail.gmail.com> <CAKW6Ri6ueXvB9xAZTVPVg=dUVhQnXeOtGS7WHRViAdtEbotqzA@mail.gmail.com> <1FAD3E3B-0815-4A45-BA7B-5C390F75F70E@isc.org>
In-Reply-To: <1FAD3E3B-0815-4A45-BA7B-5C390F75F70E@isc.org>
From: Dick Franks <rwfranks@gmail.com>
Date: Fri, 9 Jul 2021 08:00:00 +0100
Message-ID: <CAKW6Ri4=1sBrU6jPW6d+Dsheb6Vn-OY5pvX0c_72UY6WeK5HtA@mail.gmail.com>
To: Mark Andrews <marka@isc.org>
Cc: dnsop <dnsop@ietf.org>, Tim Wicinski <tjw.ietf@gmail.com>, dnsop-chairs <dnsop-chairs@ietf.org>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Archived-At: <https://mailarchive.ietf.org/arch/msg/dnsop/XNLIeRbhaXc9ZNT8JVa7aBi-qFQ>
Subject: Re: [DNSOP] New Version Notification - draft-ietf-dnsop-svcb-https-06.txt
X-BeenThere: dnsop@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: IETF DNSOP WG mailing list <dnsop.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/dnsop>, <mailto:dnsop-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/dnsop/>
List-Post: <mailto:dnsop@ietf.org>
List-Help: <mailto:dnsop-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/dnsop>, <mailto:dnsop-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 09 Jul 2021 07:01:22 -0000

On Mon, 5 Jul 2021 at 03:11, Mark Andrews <marka@isc.org> wrote:
>8

>
> Opaque key form isn’t subject to double parsing despite the hint6 having
> commas in the presentation form.  That’s about the only way you could be
> seeing that difference.  The opaque key form knows nothing about the
> internal structure, you don’t double parse opaque key form.  It’s
>

My current analysis model certainly does not rely upon double-parsing
of the opaque form.

Whatever else we might disagree about, there is one feature we can depend upon.
The devout double-escapologist believes that "standard string
processing" occurs before any SVCB-specific code is reached.
This introduces plenty of weaknesses to be exploited.

1) Chuck in an extra digit
    example.com.    SVCB    1 foo.example.com. port=1234\053
produces
    example.com.    IN      SVCB    ( \# 25 0001    ; 1
        03666f6f076578616d706c6503636f6d 00     ; foo.example.com.
        0003 0002 3039 )

instead of the expected error message.

2) Break number parsing
    example.com.    SVCB    1 foo.example.com. port=1234\078

  Argument "1234N" isn't numeric in pack at
blib/lib/Net/DNS/RR/SVCB.pm line 192, <DATA> line 2.
  file GLOB(0x556193c89ea0) line 2
  at test.pl line 23.

3) Break argument parsing
    example.com.    SVCB    1 foo.example.com. port=12\04434

  SVCB: unexpected number of values for "key3" at
blib/lib/Net/DNS/ZoneFile.pm line 531.
  file GLOB(0x559fdbb90d80) line 2
  at test.pl line 23.


--rwf