Re: FW: New Version Notification for draft-rafiee-6man-cga-attack-00.txt

Hi,

I've quickly read the draft and here are my comments:

o No comparison of source address with target address

This argument is not valid because, when SEND is used the "Target Address
in Neighbor Advertisement is required to be equal to the source address of
the packet" (cf. RFC 3971, Section 7.4)

o Ignoring Sec Value during DAD

I agree with Christian: the check is done over the complete target address
(i.e., including Prefix, Sec value, u/g bits)
Indeed, DAD fails, when receiving a NA message, "if the target address is
tentative", meaning "the tentative address is not unique" (cf. RFC 4862,
Section 5.4.4).

So, IMHO, your argument is not valid.

o Collision vs. Pre-image attack

IMHO, you assume that attack is a real-time one: when a victim node
generates a CGA (in fact, an IID), with your attack, the malicious node
wants to generate the same _given_ CGA (in fact, the same IID).
So, I agree with Marcelo: this is a pre-image attack ...or a second
pre-image attack (as the malicious node knows the CGA parameters).

o RSA private/public keys

One point I don't understand in your attack is that, even if you find a
collision, meaning you "find" a potential value for the public key, how did
you get the associated private key needed to generate the RSA Signature
option and providing the CGA's proof of ownership?

Thanks in advance for your reply.

Best regards,

JMC.

2013/11/25 Hosnieh Rafiee <ietf@rozanak.com>

> Here you go! Sorry for typos or bad organization since I wrote it so fast.
> The next versions will be better.
>
> BTW, as I explained in my previous message, you can bombard me with too
> many emails but please do not expect immediate answer for the next 3
> upcoming days since I will have limited internet access.
>
> -----------smile----------
> Hosnieh
>
>
>
> A new version of I-D, draft-rafiee-6man-cga-attack-00.txt
> has been successfully submitted by Hosnieh Rafiee and posted to the IETF
> repository.
>
> Filename:        draft-rafiee-6man-cga-attack
> Revision:        00
> Title:           Possible Attack on Cryptographically Generated Addresses
> (CGA)
> Creation date:   2013-11-25
> Group:           Individual Submission
> Number of pages: 7
> URL:
> http://www.ietf.org/internet-drafts/draft-rafiee-6man-cga-attack-00.txt
> Status:
> http://datatracker.ietf.org/doc/draft-rafiee-6man-cga-attack
> Htmlized:
> http://tools.ietf.org/html/draft-rafiee-6man-cga-attack-00
>
>
> Abstract:
>    This document describes the new vulnerabilities with the use of
>    Cryptographically Generated Addresses.
>
>
>
>
>
>
>
>
> 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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