Return-Path: X-Original-To: ipv6@ietfa.amsl.com Delivered-To: ipv6@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 0FB8E120074 for ; Sun, 8 Dec 2019 15:50:13 -0800 (PST) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -1.997 X-Spam-Level: X-Spam-Status: No, score=-1.997 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=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 dAgzuGQQigch for ; Sun, 8 Dec 2019 15:50:10 -0800 (PST) Received: from mail-io1-xd29.google.com (mail-io1-xd29.google.com [IPv6:2607:f8b0:4864:20::d29]) (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 A1EC812002F for ; Sun, 8 Dec 2019 15:50:10 -0800 (PST) Received: by mail-io1-xd29.google.com with SMTP id s2so12834906iog.10 for ; Sun, 08 Dec 2019 15:50:10 -0800 (PST) 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; bh=XSMO0vM5od9bmneX8z0Y1qDKSgK3unprzoHQpPdvCN0=; b=Nii2xOsiIZW8lHa0AWip4wtWBDZjp0yaHL7pjPkSPcQutVq7S4AFXNtxge618HwOOf ksNiH3Iz/ONFpx6eFAb0yFhCrkFvWYGUbYwhMMhkLX/Gm6/BY9tclxKlSBfdlb/y5spS pu+ftevcXxLoJzd0WC4EvwdPdbEA1jnCIHzomTJMtPugmD/Xzl0a3r/SI52pVAzHQ1iG srhuOqiGCvr8F+abYptb2J0aDUPGdg61RsSQ5Xyb29/y5uSfnZzeCmFj0xjUiXfvhx6g yWyO/JJhC2QAXVBcZyL+s9MfZvrhKpR+Rj7RDbFx6gR38dU7+UePieKUGftKzd0NatE2 Q2nA== 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=XSMO0vM5od9bmneX8z0Y1qDKSgK3unprzoHQpPdvCN0=; b=qka6pnRdpTXVmPBiZr/+V+7tRDkY8oQlIV3N7XW0tjrhlPcw1J/91vvaVn+TMQmtOB HF9EgQhWTi3+jjN2Brvyu96JeH47zPOJuGAa+VV/w608C31pNUZkDqEz/Jto8o8zt2EA yYkcUWcg2O/GT8pWIKSpYmeuG0vLp8MRhb8GEQiVlLrX5o1YodNzUhU6HCeJir1e3Y8y OSQXmLOcSEfCFfdY7FZ6RtpKexAHHGOieg0nm0az2qSQuCIFhJJ5oP1zRA3T9G7Keckr Plozo4NT/Afe4gzAt5sT1JVUTUL+txK5Kd8czHF60eG35xGsmbuiktY1Y7Rpq+6KlBR8 Lv/g== X-Gm-Message-State: APjAAAWsRIrN0dfm6MplgU4Rgrru+aHjZSkW+R+o72W9Vy5baOERt8gQ rdrnjNPdof+SAK1UCdAzcxaEsEoxOGVIoW11CLY= X-Google-Smtp-Source: APXvYqzzMI5ILS6M8yu2U1MP12SrdCx3Rn0lCV15Y5FEbMb+vfnfQMJOI1m7qE6rdoq1MC9wUZKqrvHCM6ng+YgsvE8= X-Received: by 2002:a6b:7316:: with SMTP id e22mr19459239ioh.205.1575849009726; Sun, 08 Dec 2019 15:50:09 -0800 (PST) MIME-Version: 1.0 References: <10E890EA-3278-44EE-881E-EBC91D419587@employees.org> <88287cb0-c0c3-f990-4dd7-338df87c7fb2@joelhalpern.com> <4E76C386-FB1E-4E48-814D-BB626466BEE3@employees.org> <8AE06652-D6DB-444D-A8BB-7924181C83E4@employees.org> <160F2740-7571-44D9-8995-5D2F23989DF6@employees.org> <2ecefe0e-14c1-b991-754f-c2724e3fe198@gmail.com> <51AB190F-92A6-427D-8605-0796FAB9820A@employees.org> In-Reply-To: <51AB190F-92A6-427D-8605-0796FAB9820A@employees.org> From: Gyan Mishra Date: Sun, 8 Dec 2019 18:49:58 -0500 Message-ID: Subject: Re: IPv6 header insertion in a controlled domain To: otroan@employees.org Cc: 6man WG , Brian E Carpenter Content-Type: multipart/alternative; boundary="00000000000071cc74059939f02b" Archived-At: X-BeenThere: ipv6@ietf.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "IPv6 Maintenance Working Group \(6man\)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 08 Dec 2019 23:50:13 -0000 --00000000000071cc74059939f02b Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Sun, Dec 8, 2019 at 5:03 PM wrote: > Brian, > > >>> I was thinking the obvious man in middle attack tampering with v6 > header by intermediate node and possible impact to AH if used. > >> > >> If AH is used, wouldn't A add the signature, and C when validating > would know that B added the header and could do verification accordingly? > >> For a controlled domain where all of A,B and C are acting in cohort, > then that wouldn't be too far fetched to assume. > >> At least a lot more probable than that AH would be used at all. ;-) > >> > >> Any other security issues you see? > > > > Two comments on this thread: > > > > 1) It isn't just AH that is broken; any form whatever of cryptographic > authentication of the packet header or the packet as a whole between A an= d > C is impossible unless the key is shared between A and B. But whether tha= t > matters or not is a domain-specific decision. If I'm outside the domain, > why would I care? > > Right. I think Gyan's point was that header insertion made it harder to > secure the tunnel between A and C. > So mainly a problem for the controlled domain itself. > ESP NULL would work fine probably, since it doesn't include payload lengt= h > in the signature. > And you can ensure whatever is inserted is also treated as mutable. > Regardless, this is an inside the controlled domain problem, and one coul= d > probably define a suitable security scheme for it if required. > > > 2) For me the test that matters is not whether this all works, but > whether the fact that it's happening can in principle be detected from > outside the domain. If it can't be detected from outside, why would I car= e? > > > > Note that NAT fails test 2. I'm not convinced that SRH insertion inside > a tunnel does so. > > I suppose header insertion has to pass both tests. > It has to be transparent to the outside, and it has to be possible to > secure within the domain. I think since this is within the operators domain that they have full control of maintaining the trust boundaries and enforcement of what can be seen outside the domain. A good example of this enforcement in the MPLS world is that you don=E2=80= =99t allow any entity or customer outside the operator domain to trace through the domain. Real would scenario is using the =E2=80=9Cno mpls ttl-propagat= e=E2=80=9D to prevent traceroute through an operators mpls core. My point is the onus is on the operator to enforce the boundary and allow or not allow visibly into the operators network. So 2 can be easily accomplished but the onus is on the operator. Ole had a valid point about AH that the probability of the nodes in the domain having a common security stance is more probable then the operator using AH within the domain. > > > Cheers, > Ole > -------------------------------------------------------------------- > IETF IPv6 working group mailing list > ipv6@ietf.org > Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 > -------------------------------------------------------------------- > --=20 Gyan S. Mishra IT Network Engineering & Technology Verizon Communications Inc. (VZ) 13101 Columbia Pike FDC1 3rd Floor Silver Spring, MD 20904 United States Phone: 301 502-1347 Email: gyan.s.mishra@verizon.com www.linkedin.com/in/networking-technologies-consultant --00000000000071cc74059939f02b Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable


On Sun, Dec 8, 2019 at 5:03 PM <otroan@employees.org> wrote:
Brian,

>>>=C2=A0 =C2=A0 =C2=A0I was thinking the obvious man in middle at= tack tampering with v6 header by intermediate node and possible impact to A= H if used.
>>
>> If AH is used, wouldn't A add the signature, and C when valida= ting would know that B added the header and could do verification according= ly?
>> For a controlled domain where all of A,B and C are acting in cohor= t, then that wouldn't be too far fetched to assume.
>> At least a lot more probable than that AH would be used at all. ;-= )
>>
>> Any other security issues you see?
>
> Two comments on this thread:
>
> 1) It isn't just AH that is broken; any form whatever of cryptogra= phic authentication of the packet header or the packet as a whole between A= and C is impossible unless the key is shared between A and B. But whether = that matters or not is a domain-specific decision. If I'm outside the d= omain, why would I care?

Right. I think Gyan's point was that header insertion made it harder to= secure the tunnel between A and C.
So mainly a problem for the controlled domain itself.
ESP NULL would work fine probably, since it doesn't include payload len= gth in the signature.
And you can ensure whatever is inserted is also treated as mutable.
Regardless, this is an inside the controlled domain problem, and one could = probably define a suitable security scheme for it if required.

> 2) For me the test that matters is not whether this all works, but whe= ther the fact that it's happening can in principle be detected from out= side the domain. If it can't be detected from outside, why would I care= ?
>
> Note that NAT fails test 2. I'm not convinced that SRH insertion i= nside a tunnel does so.

I suppose header insertion has to pass both tests.
It has to be transparent to the outside, and it has to be possible to secur= e within the domain.


=C2=A0 =C2=A0I think since this is within t= he operators domain that they have full control of maintaining the trust bo= undaries and enforcement of what can be seen outside the domain.=C2=A0

A good example of this enfor= cement in the MPLS world is that you don=E2=80=99t allow any entity or cust= omer outside the operator domain to trace through the domain.=C2=A0 Real wo= uld scenario is using the =E2=80=9Cno mpls ttl-propagate=E2=80=9D to preven= t traceroute through an operators mpls core.

My point is the onus is on the operator to enforce the= boundary and allow or not allow visibly into the operators network.=C2=A0 = So 2 can be easily accomplished but the onus is on the operator.

Ole had a valid point about AH tha= t the probability of the nodes in the domain having a common security stanc= e is more probable then the operator using AH within the domain.


Cheers,
Ole
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<= div dir=3D"ltr">

Gyan S. Mishra

IT Networ= k Engineering & Technology=C2=A0=

Verizon Communications=C2=A0Inc. (VZ)=

13101 Columbia Pike FDC1 3rd Floor

=

Silver Spring, MD 20904

United States<= span style=3D"color:rgb(80,0,80);background-image:initial;background-positi= on:initial;background-repeat:initial">

Phone:=C2=A0301 502-1347

Email:=C2=A0gyan.s.mishra@verizon.= com

www.linkedin.com/in/networking-technologies-co= nsultant


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