On 05 Dec 2013, at 11:56, Albert Cabellos <[email protected]> wrote:

> Hi,
> 
> On 04/12/2013 22:40, Damien Saucez wrote:
> 
> [snip]
>>> * Section 4.3.2.2->RFC6830 already recommends rate-limiting Map-Requests,
>>> hence there is a limit on the amplification attack.
>>> 
>> 
>> I think the analysis is complementary to the recommendation.  In
>> RFC6830, no reason is given about why rate limit, here it shows why
>> this is recommended.
>> 
> I agree, but the text seems to suggest that the amplification attack scales 
> linearly and it is bounded to the maximum bandwidth (in control messages per 
> second) of the attacker, this is not true. The attack is bounded by the 
> rate-limit set at the xTR.
> 
>>> 
>>> * Section 4.3.2.3->I´m having a hard time understanding this attack,
>>> even under attack, the ETR will reply with the "real nonce", at least
>>> once. Probably I´m missing something.
>>> 
>>> 
>> 
>> sure but if an attacker floods with random nonce, then when the node
>> will answer with the real nonce, it will already have been changed to
>> another one sent by the attacker.
>> 
> 
> Right, thanks. What about recommending that each nonce should be used at 
> least once? So that a nonce can´t be overwritten if it has not been used.
> 

Isn't that the definition of a nonce? I don't see how it helps.

Imagine

- Legit sends Nonce1 
- Bad guy sends Nonce2 with spoof address of Legit
- Nonce1 arrives, but it is too late, it has been overridden by Nonce2
already so the return with Nonce1is just ignored.

>>> * Section 4.4.1-> In some cases the SMR-invoked Map-Request is sent
>>> through the mapping system (not directly to the source RLOC), in this
>>> case the attack is still effective and involves the Mapping System, the
>>> Map-Server and the xTR (if operating in non-proxy mode).
>>> 
>> 
>> I am not sure I understand your question here.
>> 
> 
> I´m referring to this paragraph:
> 
> "  The Map-Request message may also contain the SMR bit.  Upon reception
>    of a Map-Request message with the SMR bit, an ETR must return to the
>    source of the Map-Request message a Map-Request message to retrieve
>    the corresponding mapping.  This raises similar problems as the RLOC
>    record P bit discussed above except that as the Map-Request messages
>    are smaller than Map-Reply messages, the risk of amplification
>    attacks is reduced. "
> 
> In some cases the SMR-invoked Map-Request is sent through the Mapping System 
> (RFC6830):
> 
> "      If the source Locator is the only
>        Locator in the cached Locator-Set, the remote ITR SHOULD send a
>        Map-Request to the database mapping system just in case the
>        single Locator has changed and may no longer be reachable to
>        accept the Map-Request."
> So my point is that the attack is similar (true) but in some cases the 
> amplification attack is through the Mapping System. Again the attack is 
> bounded by the rate-limit set the xTR. In my view this should be also stated.

ok, we could say so

Damien Saucez

> 
> Regards
> 
> Albert
>> 
>>> Editorial, please consider them suggestions, at the end it is a matter
>>> of taste of the writer/reader.
>> 
>> ok, will take them into account according to other reviews.
>> 
>>> > 1.  Introduction
>>> >
>>> >    The Locator/ID Separation Protocol (LISP) is defined in [RFC6830].
>>> 
>>> specified instead of defined?
>>> 
>>> >    The present document assesses the security level and identifies
>>> >    security threats in the LISP specification if LISP is deployed in the
>>> >    Internet (i.e., a public non-trustable environment).  As a result of
>>> >    the performed analysis, the document discusses the severity of the
>>> >    threats and proposes recommendations to reach the same level of
>>> >    security in LISP than in Internet today (e.g., without LISP).
>>> 
>>> "(i.e., without LISP)" (not e.g.,) I understand that the authors are not
>>> referring to an example.
>>> 
>>> >    This document does not consider all the possible uses of LISP as
>>> >    discussed in [RFC6830].  The document focuses on LISP unicast,
>>> >    including as well LISP Interworking [RFC6832], LISP-MS [RFC6833], and
>>> >    LISP Map-Versioning [RFC6834].  The reading of these documents is a
>>> >    prerequisite for understanding the present document.
>>> 
>>> Several deployment scenarios are discussed in
>>> draft-ietf-lisp-deployment, please consider citing it and discussing if
>>> the use-cases described in the deployment draft are covered by this
>>> analysis.
>>> 
>>> >    SA  is an off-path attacker that is able to send spoofed packets,
>>> >        i.e., packets with a different source IP address than its
>>> >        assigned IP address.  SA stands for Spoofing Attacker.
>>> 
>>> SA attackers need access to the RLOC space, it might make sense to state
>>> this here.
>>> 
>>> > 4.3.1.2.  Threats concerning Interworking
>>> >
>>> >    [RFC6832] defines Proxy-ITR And Proxy-ETR network elements to allow
>>> 
>>> Edit "and" instead of "And"
>>> 
>>> On 02/12/2013 3:02, Terry Manderson wrote:
>>>> I would just like to highlight that the end of this LC draws near.
>>>> 
>>>> Without review, this document cannot move forward.
>>>> 
>>>> Cheers
>>>> Terry
>>>> 
>>>> On 20/11/13 9:23 AM, "Terry Manderson" <[email protected]> wrote:
>>>> 
>>>>> All,
>>>>> 
>>>>> As requested in Vancouver, the authors of draft-ietf-lisp-threats-08 have
>>>>> requested a work group last call.
>>>>> 
>>>>> Here starts a 14 day last call for this document, the last call will end
>>>>> on
>>>>> Wednesday 4th December 2013.
>>>>> 
>>>>> You will find its text here:
>>>>> http://tools.ietf.org/html/draft-ietf-lisp-threats-08
>>>>> 
>>>>> Please review this WG item and provide any last comments.
>>>>> 
>>>>> Cheers
>>>>> Terry
>>>>> 
>>>>> 
>>>>> _______________________________________________
>>>>> lisp mailing list
>>>>> [email protected]
>>>>> https://www.ietf.org/mailman/listinfo/lisp
>>> 
>>> _______________________________________________
>>> lisp mailing list
>>> [email protected]
>>> https://www.ietf.org/mailman/listinfo/lisp
>> 
> 

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