Re: [IPsec] ikev2 algorithms, Initiator choice preferred over responder ?

2012-10-25 Thread Yoav Nir
Hi Kalyani

The spec is silent on how the responder chooses the algorithm from among the 
choices offered by the initiator. It can choose by giving priority to its own 
preferences, or by choosing the first proposal that is allowed by its policy. 
Since it does not affect interoperability, the RFC does not specify this.

Yoav

On Oct 24, 2012, at 6:23 AM, Kalyani Garigipati (kagarigi) wrote:

 
 Hi ,
 
 If the initiator proposes three algorithms say alg1, alg2. Alg3 for 
 encryption in SA1.
 And responders choice is in the order as  alg3,alg2,alg1, then finally in 
 SA_INIT response what should be sent as the algorithm.
 
 From the RFC I felt that it is the initiator choice that should be given 
 preference and so responder MUST send alg1 in response.
 Or is it that responder MUST be given preference and it MUST send alg3 in 
 response ?
 
 I could not locate any paras in RFC which gives clear guidelines on this.
 Please let me know if anything like this is already mentioned otherwise I 
 think it should be added in clarifications.
 
 Regards,
 Kalyani

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Re: [IPsec] ikev2 algorithms, Initiator choice preferred over responder ?

2012-10-24 Thread Michael Richardson

Kalyani Garigipati (kagarigi) kagar...@cisco.com wrote:
KG If the initiator proposes three algorithms say alg1, alg2. Alg3
KG for encryption in SA1.  And responders choice is in the order as
KG alg3,alg2,alg1, then finally in SA_INIT response what should be
KG sent as the algorithm.

Why would the responder reply with three choices?  The spec doesn't say that.
It's not a negotiation.  If the responder has a preference, it should
simply state that one preference in the reply.

KG From the RFC I felt that it is the initiator choice that should
KG be given preference and so responder MUST send alg1 in response.
KG Or is it that responder MUST be given preference and it MUST
KG send alg3 in response ?

The responder is free to answer whatever it thinks it should based upon
local policy.


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From: Kalyani Garigipati (kagarigi) kagar...@cisco.com
To: ipsec@ietf.org ipsec@ietf.org
Date: Wed, 24 Oct 2012 04:23:14 +
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Subject: [IPsec] ikev2 algorithms,
Initiator choice preferred over responder ?
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Hi ,

If the initiator proposes three algorithms say alg1, alg2. Alg3 for encryption 
in SA1.
And responders choice is in the order as  alg3,alg2,alg1, then finally in 
SA_INIT response what should be sent as the algorithm.

From the RFC I felt that it is the initiator choice that should be given 
preference and so responder MUST send alg1 in response.
Or is it that responder MUST be given preference and it MUST send alg3 in 
response ?

I could not locate any paras in RFC which gives clear guidelines on this.
Please let me know if anything like this is already mentioned otherwise I think 
it should be added in clarifications.

Regards,
Kalyani



-- 
Michael Richardson
-on the road-




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[IPsec] ikev2 algorithms, Initiator choice preferred over responder ?

2012-10-23 Thread Kalyani Garigipati (kagarigi)

Hi ,

If the initiator proposes three algorithms say alg1, alg2. Alg3 for encryption 
in SA1.
And responders choice is in the order as  alg3,alg2,alg1, then finally in 
SA_INIT response what should be sent as the algorithm.

From the RFC I felt that it is the initiator choice that should be given 
preference and so responder MUST send alg1 in response.
Or is it that responder MUST be given preference and it MUST send alg3 in 
response ?

I could not locate any paras in RFC which gives clear guidelines on this.
Please let me know if anything like this is already mentioned otherwise I think 
it should be added in clarifications.

Regards,
Kalyani

-Original Message-
From: ipsec-boun...@ietf.org [mailto:ipsec-boun...@ietf.org] On Behalf Of Sean 
Turner
Sent: Monday, October 22, 2012 5:56 PM
To: Dan Harkins
Cc: ipsec@ietf.org
Subject: Re: [IPsec] brainpool summary, suggested way ahead, and comments on 
draft

Dan,

I've exchange some emails with with Johannes Merkle about adding cipher suites 
to TLS.  What he's agreed to do is to include only three points 
(BrainpoolP256r1, BrainpoolP384r1, and BrainpoolP512r1) in the draft.

spt

On 10/19/12 3:20 AM, Dan Harkins wrote:

Sean,

It was a two-part request. I'd like the IESG to follow the same 
 process they followed for what became RFC 5114.

Is there a way to get an RFC published to update this registry that 
 does not need to go through the IESG? If not then the 2nd part is the 
 critical one; if so then we can just end this fiasco now.

regards,

Dan.

 On Thu, October 18, 2012 7:58 am, Sean Turner wrote:
 Dan,

 There's not need to ask the IESG about the process to update the 
 registry in question it's clear: RFC required.  You can get an RFC 
 through a WG, through an AD, or through the ISE.

 spt

 On 10/15/12 10:54 PM, Dan Harkins wrote:

 Hi Sean,

 On Mon, October 15, 2012 5:00 pm, Sean Turner wrote:

 On 10/12/12 2:32 AM, Dan Harkins wrote:

 On Thu, October 11, 2012 5:47 pm, Sean Turner wrote:

 I'm going to run my proposal and Michael's by the IESG on an 
 informal telechat to see which one's got the best chance of 
 getting through the process to resolve the IEEE's request.

  Can you ask the IESG to just do what it has done in the past? 
 That is, just update the registry to include code points for new 
 curves without any bizarre notes or pointers? No fuss, no mess, 
 just a few new rows in a table.

  The worst that could happen if the IESG agrees to do that is 
 that someone somewhere might use a brainpool curve with IKEv1. The 
 odds are slim, but they're not zero. And if that happens then so 
 what? Really. So what?

 The RFC 5114 example wasn't published to address another SDO 
 request for a code point so I don't think it's the same situation.

 That's certainly a distinction but I don't see how that matters. 
 You could also note that RFC 5114 added MODP groups as well as ECP 
 groups. Also a distinction that really doesn't matter.

 Again, the SDO request is a _by-product_ of the opposition to 
 just letting Johannes' draft update the registry. It is this same 
 opposition that is creating these problems about notes and pointers 
 and the concern over whether they will have the desired effect and 
 what we should do to ensure they do. If this opposition had not 
 materialized there never would've been another SDO request.

 It is the same situation, indulge me here a bit:

 What we had was another organization (NIST) came up with some 
 new DH groups and there was a proposal to add them to both IKEv1 and 
 IKEv2 registries. And now, quite similarly, there's another 
 organization (the ECC
 Brainpool) that came up with some new DH groups and there was a 
 proposal to add them to both IKEv1 and IKEv2 registries.

 When the proposal was made to add the NIST groups to the IKEv1 
 registry there was no hullabaloo over updating a deprecated 
 protocol's registry and there was no concern that someone somewhere 
 might use the NIST groups with IKEv1.

 But when Johannes made his proposal to add the ECC Brainpool 
 curves to the IKEv1 registry there was all of a sudden a hullabaloo 
 and much concern that someone somewhere might use the ECC Brainpool 
 groups with IKEv1.

 So my request to you is to ask that the IESG consider what the 
 process defined for updating this registry is (it's RFC required) 
 and to note that there is precedence to update the registry of this 
 deprecated protocol.
 So please ask the IESG to just approve a draft (either Johannes' or
 mine)
 for publication as an RFC to update this registry in the same manner 
 that RFC 5114 updated it (i.e. no notes, no pointers, no nonsense).

  Then there'd be no need for the IESG to have a discussion about 
 the (de)merits of notes and pointers in registries and how best to 
 ensure that no one nowhere ever even thinks about using an ECC 
 Brainpool curve in
 IKEv1 and that certainly sounds like a better use