Re: [IPsec] Fw: New Version Notification for draft-smyslov-ipsecme-ikev2-null-auth-00.txt

Hi Valery,

Yes, between EAP+signature (RFC 5996) and EAP+EAP (RFC 5998), there's 
very little justification for EAP+null, and it is very likely to create 
security issues. I think we should mention EAP, and expressly forbid it 
in this context (MUST NOT).

Thanks,
	Yaron

On 12/25/2013 07:18 AM, Valery Smyslov wrote:
> Hi Yaron,
>
>> Hi Valery,
>>
>> Thanks for posting this draft.
>>
>> One quick comment: the interaction of your proposal with EAP is not
>> clear to me, i.e. when one peer uses Null auth and the other uses EAP.
>> There are cases where this should be forbidden (e.g. MSCHAP, where the
>> unauthenticated peer can mount a dictionary attack) and other cases
>> where this is OK. Specifically, for the methods listed as "safe" in
>> Sec. 4 of RFC 5998, I believe this use would be secure.
>
> Actually, I think that NULL Auth should not be used with EAP.
> Section 2.16 of RFC5996 states:
>
>    In addition to authentication using public key signatures and shared
>    secrets, IKE supports authentication using methods defined in RFC
>    3748 [EAP].  Typically, these methods are asymmetric (designed for a
>    user authenticating to a server), and they may not be mutual.  For
>    this reason, these protocols are typically used to authenticate the
>    initiator to the responder and MUST be used in conjunction with a
>    public-key-signature-based authentication of the responder to the
>    initiator.
>
> I agree with you, that in some cases using NULL Auth with EAP
> might be secure, but as IKEv2 already requires responder
> to use signature auth with EAP, I don't see any reason to change it.
>
> Do you think it's worth to mention that in the draft and provide
> a reference to the text from RFC5996?
>
>> Happy holidays!
>
>> Yaron
>
> Happy New Year!
>
> Valery.
>
>> On 12/24/2013 03:47 PM, Valery Smyslov wrote:
>>> Hi all,
>>>
>>> I've just posted a draft, defining NULL Authentication method in IKEv2.
>>> This method may be used for anonymous access or in situations,
>>> when peers don't have any trust relationship, but still want
>>> to get protection at least against passive attacks.
>>>
>>> Regards,
>>> Valery.
>>>
>>>
>>> ----- Original Message ----- From: <internet-drafts@ietf.org>
>>> To: "Valery Smyslov" <svan@elvis.ru>; "Valery Smyslov" <svan@elvis.ru>
>>> Sent: Tuesday, December 24, 2013 5:40 PM
>>> Subject: New Version Notification for
>>> draft-smyslov-ipsecme-ikev2-null-auth-00.txt
>>>
>>>
>>>
>>> A new version of I-D, draft-smyslov-ipsecme-ikev2-null-auth-00.txt
>>> has been successfully submitted by Valery Smyslov and posted to the
>>> IETF repository.
>>>
>>> Name: draft-smyslov-ipsecme-ikev2-null-auth
>>> Revision: 00
>>> Title: The NULL Authentication Method in IKEv2 Protocol
>>> Document date: 2013-12-24
>>> Group: Individual Submission
>>> Pages: 8
>>> URL:
>>> http://www.ietf.org/internet-drafts/draft-smyslov-ipsecme-ikev2-null-auth-00.txt
>>>
>>>
>>> Status:
>>> https://datatracker.ietf.org/doc/draft-smyslov-ipsecme-ikev2-null-auth/
>>> Htmlized:
>>> http://tools.ietf.org/html/draft-smyslov-ipsecme-ikev2-null-auth-00
>>>
>>>
>>> Abstract:
>>>    This document defines the NULL Authentication Method for IKEv2
>>>    Protocol.  This method provides a way to omit peer authentication in
>>>    IKEv2 and to explicitely indicate it in the protocol run.  This
>>>    method may be used to preserve anonymity or in situations, where no
>>>    trust relationship exists between the parties.
>>>
>>>
>>>
>>>
>>> Please note that it may take a couple of minutes from the time of
>>> submission
>>> until the htmlized version and diff are available at tools.ietf.org.
>>>
>>> The IETF Secretariat
>>>
>>> _______________________________________________
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>