Subject: 6man Agenda for the Philadelphia IETF

From: Bob Hinden <[email-masked]>
Date: Wed, 5 Mar 2008 10:50:49 -0800

Hi,

The agenda for the 6man session for the Philadelphia IETF is posted at:

   http://www.ietf.org/proceedings/08mar/agenda/6man.txt

Let us know if we missed anything.

The presenters should send us their slides the day before the meeting  
so we can upload them to the IETF site so they will be available for  
people not in the room.

Thanks,
Bob & Brian

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From: <[email-masked]>
Date: Wed, 5 Mar 2008 13:46:29 -0600

Hi all,

The RFC 4294-bis draft has the following requirement, which comes from
the initial RFC.

 8.1. Basic Architecture

   Security Architecture for the Internet Protocol [RFC-4301] MUST be
   supported.

 8.2. Security Protocols

   ESP [RFC-4303] MUST be supported.  AH [RFC-4302] MUST be supported.

We have had a lot of discussion that people basically feel that these
requirements
are not applicable and should be moved to SHOULD.  I would say that
there is rough
WG Consensus on this.  Do people feel if there should be additional text
to explain
this?

I suggest that the WG Chairs and our ADs discuss this with the Security
ADs to ensure
that this is a reasonable consensus to adopt - so that we do not run
into issues
during the eventual IETF/IESG review.  I am not sure that we can go much
further in 
discussions in the WG.

Does anyone have comments on this approach?

John

---

From: "Vishwas Manral" <[email-masked]>
Date: Wed, 5 Mar 2008 12:12:22 -0800

Hi John,

RFC4301 states AH is optional. Is there a reason why we are making it
a MUST be supported feature. Below quoting RFC4301:

"IPsec implementations MUST support ESP and MAY
   support AH."

Thanks,
Vishwas

---

From: <[email-masked]>
Date: Wed, 5 Mar 2008 14:14:33 -0600

Sorry, that was a cut & paste mistake. AH is a MAY.

John 

>-----Original Message-----
>From: ext Vishwas Manral [mailto:[email-masked]] 
>Sent: 05 March, 2008 12:12
>To: Loughney John (Nokia-OCTO/PaloAlto)
>Cc: [email-masked]
>Subject: Re: Security Requirements for IPv6 Node Req summary
>
>Hi John,
>
>RFC4301 states AH is optional. Is there a reason why we are 
>making it a MUST be supported feature. Below quoting RFC4301:
>
>>  The RFC 4294-bis draft has the following requirement, which comes 
>> from  the initial RFC.
>>
>>   8.1. Basic Architecture
>>
>> requirements  are not applicable and should be moved to SHOULD.  I 
>> would say that  there is rough  WG Consensus on this.  Do 
>people feel 
>> if there should be additional text  to explain  this?
>>
>>  I suggest that the WG Chairs and our ADs discuss this with the 
>> Security  ADs to ensure  that this is a reasonable consensus 
>to adopt 
>> - so that we do not run  into issues  during the eventual IETF/IESG 
>> review.  I am not sure that we can go much  further in  
>discussions in 
>> the WG.
>>

---

From: Brian E Carpenter <[email-masked]>
Date: Thu, 06 Mar 2008 10:21:40 +1300

If we write a SHOULD we really do need some guidance
as to when it doesn't apply. Otherwise we make it too
easy for product managers to simply cross it off the list.
How about

  The normal expectation is that a complete IPv6 stack
  includes an implementation of ESP. However, it is
  recognized that some stacks, implemented for low-end
  devices that will be deployed for special purposes
  where strong security is provided by other protocol
  layers, may omit ESP.

Regards
   Brian Carpenter
   University of Auckland

---

From: Bob Hinden <[email-masked]>
Date: Wed, 5 Mar 2008 16:16:02 -0800

Brian,

>   where strong security is provided by other protocol

We might also want to be more specific such as:

  s/provided by other protocol layers/provided by higher layer  
security protocols such as SSH and or SSL/

with appropriate references.

Speaking for myself, I want all IPv6 devices to be reasonably  
secure.  For many devices SSH and/or SSL is a fine way to provide  
secure access.  ESP isn't necessary or very useful.

Bob

---

From: "Dunn, Jeffrey H." <[email-masked]>
Date: Thu, 6 Mar 2008 11:24:27 -0500

I also suggest that the AH requirement be SHOULD, or even better MUST,
for nodes implementing OSPFv3, RFC 2740.  This is based on the removal
of the authentication LSA from OSPFv3, which was done with the
expectation that AH would be mandatory.  Thoughts?

Best Regards,
 
Jeffrey Dunn
Info Systems Eng., Lead
MITRE Corporation.
-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of
Brian E Carpenter
Sent: Wednesday, March 05, 2008 4:22 PM
To: [email-masked]
Cc: [email-masked]
Subject: Re: Security Requirements for IPv6 Node Req summary

Regards
   Brian Carpenter
   University of Auckland

>>>  Administrative Requests:
https://www.ietf.org/mailman/listinfo/ipv6

---

From: "Vishwas Manral" <[email-masked]>
Date: Thu, 6 Mar 2008 11:45:28 -0800

Hi Jeff,

You are close but still not quite there.

OSPFv2 had some fields in all packets (LSA is not a packet but a
content in a packet) to send a Hash along with the packet for
authetication. It was not used in OSPFv3 because of the assumption
that all nodes will support ESP and the packets can anyway be
encapsulated in the ESP header.

This does not however anyway justify why AH should be made a SHOULD.

Thanks,
Vishwas

---

From: "Tony Hain" <[email-masked]>
Date: Thu, 6 Mar 2008 17:49:44 -0800

ESP == MUST  &&   AH == MUST

There is a major problem with ESP/NULL & firewalls, so AH has to be there.
The crap about lack of an API as a reason to downgrade the requirement for
both of these is nothing more than a concession to IETF politics, where 'we
don't define APIs' was the mantra at the point in time this was played out
before.

You will never make progress if you constantly retreat in the face of
resistance...

Tony

> [email-masked]
> Sent: Wednesday, March 05, 2008 12:15 PM
> To: [email-masked]
> Cc: [email-masked]
> Subject: RE: Security Requirements for IPv6 Node Req summary
>

---

From: "Dunn, Jeffrey H." <[email-masked]>
Date: Thu, 6 Mar 2008 22:13:54 -0500

Vishwas,

Fair enough, I was equating the LSA with the OSPFv2 message that
carried the LSA.  In the case of cryptographic authentication, the
message digest is appended to the message.  The point is that there is
the provision for computing a message digest over the entire 

Actually, I believe that your conclusion is erroneous.  RFC 2740 was
accepted while RFC 2401 was still in effect.  As a result, the
assumption was that AH was still required.  

I believe that the real issue is the following:

1. Simply authenticating the message contents, as in the case of
ESP-NULL, does not authenticate the sender.
2. Since ESP-NULL does not provide confidentiality, anyone can view the
message contents.
3. As a result, any one can retransmit the message with a different
source IPv6 address, any one can masquerade as the original router.
4. Since the Router ID in IPv6 is not the router's IPv6 address but a
32-bit unsigned integer, a spoofed router advertisement with a valid
router advertisement is assumed to come from the IPv6 source address
5. Some one can spoof router updates and redirect traffic to themselves

If I am incorrect, please correct me.  I would prefer to believe that
we can dispense with AH and focus on integrity and confidentiality
being associated with individual users and not IP addresses.

Best Regards,
 
Jeffrey Dunn
Info Systems Eng., Lead
MITRE Corporation.
-----Original Message-----
From: Vishwas Manral [mailto:[email-masked]] 
Sent: Thursday, March 06, 2008 2:45 PM
To: Dunn, Jeffrey H.
Cc: Brian E Carpenter; [email-masked]; [email-masked]
Subject: Re: Security Requirements for IPv6 Node Req summary

Hi Jeff,

Thanks,
Vishwas

On Thu, Mar 6, 2008 at 8:24 AM, Dunn, Jeffrey H. <[email-masked]>
wrote:
>  >>>    Security Architecture for the Internet Protocol [RFC-4301]
MUST
>  be

---

From: "Vishwas Manral" <[email-masked]>
Date: Thu, 6 Mar 2008 19:43:08 -0800

Hi Tony,

You bring forward a very good point, I had raised the same issue about
3 years back in the IPsec list. There are now some drafts to add
support for the same in IPv6. The basic idea is that a middle-box(like
a firewall) should be able to identify a NULL encrypted packet.

I was however told that with some basic checks like checking some
bytes in the packet can help in determining if the upper layer packet
(and if the payload is encrypted or not). Not all firewalls currently
support this.

Thanks,
Vishwas

---

From: "Dunn, Jeffrey H." <[email-masked]>
Date: Thu, 6 Mar 2008 23:05:23 -0500

Tony,

Many thanks for amplifying my push to have AH a MUST.  You point is
well taken and one I had not though of.

Best Regards,
 
Jeffrey Dunn
Info Systems Eng., Lead
MITRE Corporation.

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of
Tony Hain
Sent: Thursday, March 06, 2008 8:50 PM
To: [email-masked]; [email-masked]
Cc: [email-masked]
Subject: RE: Security Requirements for IPv6 Node Req summary

There is a major problem with ESP/NULL & firewalls, so AH has to be
there.
The crap about lack of an API as a reason to downgrade the requirement
for
both of these is nothing more than a concession to IETF politics, where
'we
don't define APIs' was the mantra at the point in time this was played
out
before.

Tony

> >>  Does anyone have comments on this approach?
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> -
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> -

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From: "Manfredi, Albert E" <[email-masked]>
Date: Fri, 7 Mar 2008 15:40:57 -0500

> From: Dunn, Jeffrey H. [mailto:[email-masked]] 

> source IPv6 address, any one can masquerade as the original router.

I don't pretend to understand all the reasons for which AH was
downgraded to a MAY. So I'm taking that as a given.

When I saw that AH had been downgraded, even when called upon to protect
just the routing protocols, I thought that the protection available with
ESP-NULL was still adequate.

Legitimate routers which cannot decrypt the OSPFv3 message contents must
assume that the source was not legit. Whether or not the IPv6 headers
are authenticated. And by the way, it seems to me that some form of L2
encryption, or some other non-IPsec technique, should be equally up to
this task. Why isn't this adequate protection?

That aside, I agree that NULL-AH would in principle be all that's
required to protect a routing protocol, in general (there might be some
exceptions).

Bert

---

From: Brian E Carpenter <[email-masked]>
Date: Sun, 09 Mar 2008 08:30:47 +1300

It doesn't seem to me that this WG is chartered to change
the normative requirements of IPsec.

    Brian

---

From: "Vishwas Manral" <[email-masked]>
Date: Sat, 8 Mar 2008 14:03:14 -0800

Hi Brian,

You are right.

Thanks,
Vishwas