IETF Logo Mail Archive

Re: [DNSOP] SVCB ALPN value presentation format

Ben Schwartz <bemasc@google.com> Sat, 13 June 2020 15:25 UTC

Return-Path: <bemasc@google.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 00C933A003B for <dnsop@ietfa.amsl.com>; Sat, 13 Jun 2020 08:25:20 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -17.599
X-Spam-Level:
X-Spam-Status: No, score=-17.599 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_MED=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, ENV_AND_HDR_SPF_MATCH=-0.5, HTML_MESSAGE=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001, USER_IN_DEF_DKIM_WL=-7.5, USER_IN_DEF_SPF_WL=-7.5] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=google.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 LVKl5LUW8GVE for <dnsop@ietfa.amsl.com>; Sat, 13 Jun 2020 08:25:18 -0700 (PDT)
Received: from mail-wm1-x330.google.com (mail-wm1-x330.google.com [IPv6:2a00:1450:4864:20::330]) (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 381ED3A0028 for <dnsop@ietf.org>; Sat, 13 Jun 2020 08:25:18 -0700 (PDT)
Received: by mail-wm1-x330.google.com with SMTP id y20so10631604wmi.2 for <dnsop@ietf.org>; Sat, 13 Jun 2020 08:25:18 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=2CGMFJgLuWMhsRXU3a7+jvymEaj+WLgtt9MC3sA8150=; b=oQBPIEh1Lo8/VIOh2Xm1kDunjPoBWC9dOc/+qBeJkoDiGFx+ODwGPm9V/AYZ8Cq5nl 50mZvxyna9Tr68WlvNwF1JTPpFeC/82u0EzyU0wOVythMB5Pk1qI04gKb+dokDe8ZuuP Y1Q/7ME62Yfzrdd6RzbLqrTc8Jl7ICFaH4bLSdlBpqDqIklBWlIbS8BfQ/MZmm8nqVce BNqZn0MX25XyrUZqYikAJORfZ9bNZJgyrBX9CaFAkzRMjvywcMq1zMZuzqkYWrpV6hlS MD/suu+Te+DVAXXrw3WzMLX/8kTJ5+zHMmLr33L/rd+wUbogwkNm93NMoDMmX6+WK0QD WZag==
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; bh=2CGMFJgLuWMhsRXU3a7+jvymEaj+WLgtt9MC3sA8150=; b=WjsNJrRXsQiaXt5KhK/xWKISeIx9oCCQ9MP0PiGcVyQwsH9UxWq1rLtoLwgFDMQ3P5 m6RjI1U85BXfHsnZZnVraBTi7zynbVv3T6DNiMOutqIgLl88FnUR4fYK2zC3Sq9LEaTY VURP/mUqxwyhKuNj40cG1LMFutbJYI1uVE1llQoLZJlnedVGWPiCRHkfWvoYDk63m3lA kap3ISoiHtx+Qj57M9xk4NI/uag+JNACykkYbE4LZf5MzdT4zTmf8ukbLimow64TOlE6 fhhRHs8agX6UXXy8j/Q6sAM6yYTAWt9TFj00HkLvhxfq318nfCTWDUR49hXZFXToNaAy Uevw==
X-Gm-Message-State: AOAM531wuYgC/ZHTDPFhHaGWDqr28wjQ5HsoDJ0u7VXmDnKvUul0q/i6 AsypuqC3dOrszw/AL62kDJL9gk9gz/1q0cP0gXCcA5ZS
X-Google-Smtp-Source: ABdhPJxYS/nex0+GxGTB62mvhRkValqdWi3+fB+5d0E9DpmskTm7vefMOnt17tuanu59MXVU7zTXPCXBNA2dBSSy4Gw=
X-Received: by 2002:a1c:16:: with SMTP id 22mr4224154wma.42.1592061916159; Sat, 13 Jun 2020 08:25:16 -0700 (PDT)
MIME-Version: 1.0
References: <80758944-FC52-4349-9C8B-EF4083C62F1B@akamai.com>
In-Reply-To: <80758944-FC52-4349-9C8B-EF4083C62F1B@akamai.com>
From: Ben Schwartz <bemasc@google.com>
Date: Sat, 13 Jun 2020 11:25:04 -0400
Message-ID: <CAHbrMsDcvJnij9UmxJ_JBMCCxYUzq=YcG+YEd5JHVyB_H3g6Rw@mail.gmail.com>
To: Larry Campbell <lcampbel=40akamai.com@dmarc.ietf.org>
Cc: dnsop <dnsop@ietf.org>
Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg="sha-256"; boundary="00000000000002909105a7f8cda6"
Archived-At: <https://mailarchive.ietf.org/arch/msg/dnsop/ZgFmF1GUiwamBnznkZfuEEkTPyo>
Subject: Re: [DNSOP] SVCB ALPN value presentation format
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: Sat, 13 Jun 2020 15:25:20 -0000

Larry,

I think that's the intent of the current text, especially the ABNF for
"element".  If you think it's unclear, we should adjust it.  Please suggest
text!

--Ben Schwartz

On Sat, Jun 13, 2020, 10:53 AM Larry Campbell <lcampbel=
40akamai.com@dmarc.ietf.org> wrote:

> Seciont 6.1 says:
>
> > The presentation value of "alpn" is a comma-separated list of one or
> more "alpn-id"s. Any commas present in the protocol-id are escaped by a
> backslash:
> >
> >     escaped-octet = %x00-2b / "\," / %x2d-5b / "\\" / %x5D-FF
> >     escaped-id = 1*(escaped-octet)
> >     alpn-value = escaped-id *("," escaped-id)
>
> If I read this correctly, the presentation value is allowed to contain
> nulls and control characters. This seems likely to make such records very
> difficult to edit. Wouldn't it be better to require these to be encoded as
> \nnn?
>
> - lc
>
> _______________________________________________
> DNSOP mailing list
> DNSOP@ietf.org
> https://www.ietf.org/mailman/listinfo/dnsop
>

v2.23.0 | Report a Bug | By Email