[DNSOP] Conflict between "Aggressive Use" and "Wildcards"

Edward Lewis <edward.lewis@icann.org> Mon, 05 March 2018 20:19 UTC

From: Edward Lewis <edward.lewis@icann.org>
To: "dnsop@ietf.org" <dnsop@ietf.org>
Thread-Topic: Conflict between "Aggressive Use" and "Wildcards"
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Date: Mon, 05 Mar 2018 20:19:13 +0000
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Subject: [DNSOP] Conflict between "Aggressive Use" and "Wildcards"
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A few weeks ago, I came across a blog post describing a "security hole" in so-called "NSEC Aggressive Use" implementations.

https://medium.com/nlnetlabs/the-peculiar-case-of-nsec-processing-using-expanded-wildcard-records-ae8285f236be

After some exchanges of email with the blog author, I (probably not alone, but not wanting to speak for anyone else) came to a conclusion that there's a conflict between the documents "Aggressive Use of DNSSEC-Validated Cache" [1] and "The Role of Wildcards in the Domain Name System" [2].

In the latter document, this text appears in " NSEC RRSet at a Wildcard Domain Name" (section 4.7):
#    "Synthesized NSEC RRs will not be harmful as they will never be used in
#    negative caching or to generate a negative response [RFC2308]."

From this, the former document ought to list it as updating the latter document, and explain how.  This seems (said without confirming) to be the origin of the implementation difficulties.

I tried (once, a while ago) to contact the editors of the "Aggressive Use" document, but haven't gotten a response.  Suggestions?

[1] https://www.rfc-editor.org/rfc/rfc8198.txt
[2] https://www.rfc-editor.org/rfc/rfc4592.txt

[DNSOP] Conflict between "Aggressive Use" and "Wi… Edward Lewis