RFC 7793

RFC 7793 🎀 Adding 100.64.0.0/10 Prefixes to the IPv4 Locally-Served DNS Zones Registry

• Request for Comments: 7793
• Author: M. Andrews, ISC (Internet Systems Consortium) 💜
• Series: BCP 163
• Category: Best Current Practice
• Date: May 2016
• ISSN: 2070-1721
• Published by: Internet Engineering Task Force (IETF) 🌈
• Obsoletes / Updates: the title block lists neither, so this doc doesn't replace or change any other RFC 🙈

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Abstract ✨

okay so RFC 6598 says "Reverse DNS queries for Shared Address Space addresses [100.64.0.0/10] MUST NOT be forwarded to the global DNS infrastructure." 😤 that's the vibe.

this doc tells IANA to add the matching zones to the "IPv4 Locally-Served DNS Zones Registry" so those queries don't accidentally leak out to the global DNS infrastructure 🫶

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Status of This Memo 📜

This memo documents an Internet Best Current Practice.

This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on BCPs is available in Section 2 of RFC 5741.

Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7793.

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Copyright Notice 💅

Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved.

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.

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Table of Contents 🗺️

1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
2.  Changes to the IPv4 Locally-Served DNS Zones Registry . . . .   2
  2.1.  RFC 6598 Zones  . . . . . . . . . . . . . . . . . . . . .   2
3.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   5
4.  Security Considerations . . . . . . . . . . . . . . . . . . .   5
5.  Normative References  . . . . . . . . . . . . . . . . . . . .   5
Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .   6
Author's Address  . . . . . . . . . . . . . . . . . . . . . . . .   6

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1. Introduction 🦋

[RFC6598] says "Reverse DNS queries for Shared Address Space addresses [100.64.0.0/10] MUST NOT be forwarded to the global DNS infrastructure." [RFC6303] gives guidance on handling those queries, so it's the one to check 📖

This document directs IANA to add the IPv4 reverse zones that match 100.64.0.0/10 (the netblock reserved in [RFC6598]) to the "IPv4 Locally-Served DNS Zone Registry" set up by [RFC6303].

Okay, so here's the main character energy 👑 The addresses in [RFC1918] aren't expected to be seen by other parties. The addresses from [RFC6598] ARE expected to be seen by parties other than the ones deploying them 😭 That's why it matters even more that recursive nameservers serve these zones locally by default 🔥

2. Changes to the IPv4 Locally-Served DNS Zones Registry 🌸

IANA has added the zones listed in "RFC 6598 Zones" (Section 2.1) to the "IPv4 Locally-Served DNS Zone Registry".

2.1. RFC 6598 Zones 🧚

64.100.IN-ADDR.ARPA
65.100.IN-ADDR.ARPA
66.100.IN-ADDR.ARPA
67.100.IN-ADDR.ARPA
68.100.IN-ADDR.ARPA
69.100.IN-ADDR.ARPA
70.100.IN-ADDR.ARPA
71.100.IN-ADDR.ARPA
72.100.IN-ADDR.ARPA
73.100.IN-ADDR.ARPA
74.100.IN-ADDR.ARPA
75.100.IN-ADDR.ARPA
76.100.IN-ADDR.ARPA
77.100.IN-ADDR.ARPA
78.100.IN-ADDR.ARPA
79.100.IN-ADDR.ARPA
80.100.IN-ADDR.ARPA
81.100.IN-ADDR.ARPA
82.100.IN-ADDR.ARPA
83.100.IN-ADDR.ARPA
84.100.IN-ADDR.ARPA
85.100.IN-ADDR.ARPA
86.100.IN-ADDR.ARPA
87.100.IN-ADDR.ARPA
88.100.IN-ADDR.ARPA
89.100.IN-ADDR.ARPA
90.100.IN-ADDR.ARPA
91.100.IN-ADDR.ARPA
92.100.IN-ADDR.ARPA
93.100.IN-ADDR.ARPA
94.100.IN-ADDR.ARPA
95.100.IN-ADDR.ARPA
96.100.IN-ADDR.ARPA
97.100.IN-ADDR.ARPA
98.100.IN-ADDR.ARPA
99.100.IN-ADDR.ARPA
100.100.IN-ADDR.ARPA
101.100.IN-ADDR.ARPA
102.100.IN-ADDR.ARPA
103.100.IN-ADDR.ARPA
104.100.IN-ADDR.ARPA
105.100.IN-ADDR.ARPA
106.100.IN-ADDR.ARPA
107.100.IN-ADDR.ARPA
108.100.IN-ADDR.ARPA
109.100.IN-ADDR.ARPA
110.100.IN-ADDR.ARPA
111.100.IN-ADDR.ARPA
112.100.IN-ADDR.ARPA
113.100.IN-ADDR.ARPA
114.100.IN-ADDR.ARPA
115.100.IN-ADDR.ARPA
116.100.IN-ADDR.ARPA
117.100.IN-ADDR.ARPA
118.100.IN-ADDR.ARPA
119.100.IN-ADDR.ARPA
120.100.IN-ADDR.ARPA
121.100.IN-ADDR.ARPA
122.100.IN-ADDR.ARPA
123.100.IN-ADDR.ARPA
124.100.IN-ADDR.ARPA
125.100.IN-ADDR.ARPA
126.100.IN-ADDR.ARPA
127.100.IN-ADDR.ARPA

3. IANA Considerations 🍓

Per this document, IANA has added the zones listed in "RFC 6598 Zones" (Section 2.1) to the "IPv4 Locally-Served DNS Zone Registry".

IANA is reminded that an insecure delegation for these zones is required for compliance with [RFC6303] to break the DNSSEC chain of trust. 🔐

4. Security Considerations 💀

Brace yourself, this part is serious 😭 This document does not present additional security risks to the Internet than those described in [RFC6303] and [RFC6598]. So the risks are already covered by those two docs, and this one doesn't add any new ones 🫶

5. Normative References 📚

[RFC1918] Rekhter, Y., Moskowitz, B., Karrenberg, D., de Groot, G., and E. Lear, "Address Allocation for Private Internets", BCP 5, RFC 1918, DOI 10.17487/RFC1918, February 1996, http://www.rfc-editor.org/info/rfc1918.

[RFC6303] Andrews, M., "Locally Served DNS Zones", BCP 163, RFC 6303, DOI 10.17487/RFC6303, July 2011, http://www.rfc-editor.org/info/rfc6303.

[RFC6598] Weil, J., Kuarsingh, V., Donley, C., Liljenstolpe, C., and M. Azinger, "IANA-Reserved IPv4 Prefix for Shared Address Space", BCP 153, RFC 6598, DOI 10.17487/RFC6598, April 2012, http://www.rfc-editor.org/info/rfc6598.

Acknowledgements 🫶

The author would like to thank Joe Abley for his review comments. 💜

Author's Address 🖊️

M. Andrews
Internet Systems Consortium
950 Charter Street
Redwood City, CA  94063
United States

Email: marka@isc.org