[Gen-art] Re: draft-ietf-ipsecme-ikev2-downgrade-prevention-05 ietf last call Genart review

[Linda Dunbar <[e-mail]>]

Valery,

Thanks for the reply. I don't have any other comments.

Linda

-----Original Message-----
From: Valery Smyslov <[e-mail]>
Sent: Monday, June 15, 2026 3:52 AM
To: Linda Dunbar <[e-mail]>; [e-mail]
Cc: [e-mail]; [e-mail]; [e-mail]
Subject: RE: draft-ietf-ipsecme-ikev2-downgrade-prevention-05 ietf last call Genart review

Hi Linda,

thank you for your review. Please, see inline.

> Document: draft-ietf-ipsecme-ikev2-downgrade-prevention
> Title: Downgrade Prevention for the Internet Key Exchange Protocol
> Version 2
> (IKEv2) Reviewer: Linda Dunbar Review result: Ready with Nits
>
> I am the assigned Gen-ART reviewer for this draft. The General Area
> Review Team (Gen-ART) reviews all IETF documents being processed by
> the IESG for the IETF Chair.  Please treat these comments just like
> any other last call comments.
>
> For more information, please see the FAQ at
>
> <https://wiki.ietf.org/en/group/gen/GenArtFAQ>.
>
> Document: draft-ietf-ipsecme-ikev2-downgrade-prevention-??
> Reviewer: Linda Dunbar
> Review Date: 2026-06-12
> IETF LC End Date: 2026-06-12
> IESG Telechat date: Not scheduled for a telechat
>
> Summary: This draft updates IKEv2 by adding a negotiation signal and
> modified AUTH transcript so both peers authenticate the same full
> IKE_SA_INIT conversation, preventing attackers from silently
> downgrading the connection to weaker key exchange methods or stripped
> extensions
>
> Major issues: None
>
> Minor issues: None
>
> Nits/editorial comments:
>
> - Section 6 says the responder includes the notification "regardless
> of whether it was received in the request or not," and later says the
> modified authentication calculation is used only if a peer both sent
> and received the notification. Just wondering what to do when only one
> direction contains the notification.

Then the old logic (defined in Section 2.15 of RFC 7296) is used.

> - Section 4: s/Having these preconditions the goal of the attacker is
> to eavesdrop/Given these preconditions, the goal of the attacker is to
> eavesdrop/
>
> - should expand PQ/T on the first use.

Thanks, a PR is created:
https://github.com/smyslov/ikev2-downgrade-prevention/pull/46

Regards,
Valery.

>
> Best regards,
> Linda Dunbar