--- 1/draft-ietf-dnsop-extended-error-01.txt 2018-09-21 10:13:50.487452378 -0700 +++ 2/draft-ietf-dnsop-extended-error-02.txt 2018-09-21 10:13:50.515453048 -0700 @@ -1,118 +1,107 @@ Network Working Group W. Kumari Internet-Draft Google Intended status: Standards Track E. Hunt -Expires: January 3, 2019 ISC +Expires: March 25, 2019 ISC R. Arends ICANN W. Hardaker USC/ISI D. Lawrence - Akamai Technologies - July 02, 2018 + Oracle + Dyn + September 21, 2018 Extended DNS Errors - draft-ietf-dnsop-extended-error-01 + draft-ietf-dnsop-extended-error-02 Abstract This document defines an extensible method to return additional information about the cause of DNS errors. The primary use case is to extend SERVFAIL to provide additional information about the cause of DNS and DNSSEC failures. - [ Open question: The document currently defines a registry for - errors. It has also been suggested that the option also carry human - readable (text) messages, to allow the server admin to provide - additional debugging information (e.g: "example.com pointed their NS - at us. No idea why...", "We don't provide recursive DNS to - 192.0.2.0. Please stop asking...", "Have you tried Acme Anvil and - DNS? We do DNS right..." (!). Please let us know if you think text - is needed, or if a 16bit FCFS registry is expressive enough. ] - - [ Open question: This document discusses extended *errors*, but it - has been suggested that this could be used to also annotate *non- - error* messages. The authors do not think that this is a good idea, - but could be persuaded otherwise. ] - Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on January 3, 2019. + This Internet-Draft will expire on March 25, 2019. Copyright Notice Copyright (c) 2018 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 (https://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. Table of Contents - 1. Introduction and background . . . . . . . . . . . . . . . . . 3 + 1. Introduction and background . . . . . . . . . . . . . . . . . 2 1.1. Requirements notation . . . . . . . . . . . . . . . . . . 3 - 2. Extended Error EDNS0 option format . . . . . . . . . . . . . 4 + 2. Extended Error EDNS0 option format . . . . . . . . . . . . . 3 3. Use of the Extended DNS Error option . . . . . . . . . . . . 5 4. Defined Extended DNS Errors . . . . . . . . . . . . . . . . . 5 - 4.1. SERVFAIL(3) extended information codes . . . . . . . . . 6 + 4.1. SERVFAIL(2) extended information codes . . . . . . . . . 5 4.1.1. Extended DNS Error Code 1 - DNSSEC Bogus . . . . . . 6 4.1.2. Extended DNS Error Code 2 - DNSSEC Indeterminate . . 6 4.1.3. Extended DNS Error Code 3 - Signature Expired . . . . 6 4.1.4. Extended DNS Error Code 4 - Signature Not Yet Valid . 6 4.1.5. Extended DNS Error Code 5 - Unsupported DNSKEY Algorithm . . . . . . . . . . . . . . . . . . 6 4.1.6. Extended DNS Error Code 6 - Unsupported DS Algorithm . . . . . . . . . . . . . . . . . . . . 6 4.1.7. Extended DNS Error Code 7 - DNSKEY missing . . . . . 6 4.1.8. Extended DNS Error Code 8 - RRSIGs missing . . . . . 6 - 4.1.9. Extended DNS Error Code 9 - No Zone Key Bit Set . . . 7 + 4.1.9. Extended DNS Error Code 9 - No Zone Key Bit Set . . . 6 4.2. REFUSED(5) extended information codes . . . . . . . . . . 7 4.2.1. Extended DNS Error Code 1 - Lame . . . . . . . . . . 7 4.2.2. Extended DNS Error Code 2 - Prohibited . . . . . . . 7 + 4.3. NXDOMAIN(3) extended information codes . . . . . . . . . 7 + 4.3.1. Extended DNS Error Code 1 - Blocked . . . . . . . . . 7 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 5.1. new Extended Error Code EDNS Option . . . . . . . . . . . 7 5.2. new Extended Error Code EDNS Option . . . . . . . . . . . 7 6. Open questions . . . . . . . . . . . . . . . . . . . . . . . 8 7. Security Considerations . . . . . . . . . . . . . . . . . . . 8 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 9.1. Normative References . . . . . . . . . . . . . . . . . . 9 9.2. Informative References . . . . . . . . . . . . . . . . . 9 - Appendix A. Changes / Author Notes. . . . . . . . . . . . . . . 10 + Appendix A. Changes / Author Notes. . . . . . . . . . . . . . . 9 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10 1. Introduction and background There are many reasons that a DNS query may fail, some of them transient, some permanent; some can be resolved by querying another server, some are likely best handled by stopping resolution. + Unfortunately, the error signals that a DNS server can return are very limited, and are not very expressive. This means that applications and resolvers often have to "guess" at what the issue is - e.g the answer was marked REFUSED because of a lame delegation, or because of a lame delegation or because the nameserver is still starting up and loading zones? Is a SERVFAIL a DNSSEC validation issue, or is the nameserver experiencing a bad hair day? A good example of issues that would benefit by additional error information is an error caused by a DNSSEC validation issue. When a @@ -229,22 +218,21 @@ intended to be extensible, and additional codepoints will be registered in the "Extended DNS Errors" registry. This document provides suggestions for the R flag, but the originating server may ignore these recommendations if it knows better. The RESPONSE-CODE and the INFO-CODE from the EDE EDNS option is used to serve as a double index into the "Extended DNS Error codes" IANA registry, the initial values for which are defined in the following sub-sections. -4.1. SERVFAIL(3) extended information codes - +4.1. SERVFAIL(2) extended information codes 4.1.1. Extended DNS Error Code 1 - DNSSEC Bogus The resolver attempted to perform DNSSEC validation, but validation ended in the Bogus state. The R flag should not be set. 4.1.2. Extended DNS Error Code 2 - DNSSEC Indeterminate The resolver attempted to perform DNSSEC validation, but validation ended in the Indeterminate state. The R flag should not be set. @@ -298,20 +286,27 @@ An authoritative or recursive resolver that receives a query from an "unauthorized" client can annotate its REFUSED message with this code. Examples of "unauthorized" clients are recursive queries from IP addresses outside the network, blacklisted IP addresses, local policy, etc. Implementations SHOULD allow operators to define what to set the R flag to in this case. +4.3. NXDOMAIN(3) extended information codes + +4.3.1. Extended DNS Error Code 1 - Blocked + + The resolver attempted to perfom a DNS query but the domain is + blacklisted due to a security policy. The R flag should not be set. + 5. IANA Considerations [This section under construction, beware. ] 5.1. new Extended Error Code EDNS Option This document defines a new EDNS(0) option, entitled "Extended DNS Error", assigned a value of TBD1 from the "DNS EDNS0 Option Codes (OPT)" registry [to be removed upon publication: [http://www.iana.org/assignments/dns-parameters/dns- @@ -350,46 +345,41 @@ 6. Open questions 1 Can this be included in *any* response or only responses to requests that included an EDNS option? Resolvers are supposed to ignore additional. EDNS capable ones are supposed to simply ignore unknown options. I know the spec says you can only include EDNS0 in a response if in a request -- it is time to reevaluate this? - 2 Can this be applied to *any* response, or only error responses? - - 3 Should textual information be allowed as well? What if the only - thing allowed is a domain name, e.g to point at where validation - began failing? - 7. Security Considerations DNSSEC is being deployed - unfortunately a significant number of clients (~11% according to [GeoffValidation]), when receiving a SERVFAIL from a validating resolver because of a DNSSEC validaion issue simply ask the next (non-validating) resolver in their list, and don't get any of the protections which DNSSEC should provide. This is very similar to a kid asking his mother if he can have another cookie. When the mother says "No, it will ruin your dinner!", going off and asking his (more permissive) father and getting a "Yes, sure, cookie!". 8. Acknowledgements The authors wish to thank Geoff Huston and Bob Harold, Carlos M. Martinez, Peter DeVries, George Michelson, Mark Andrews, Ondrej Sury, - Edward Lewis, Paul Vixie, Shane Kerr. They also vaguely remember - discussing this with a number of people over the years, but have - forgotten who all they were -- if you were one of them, and are not - listed, please let us know and we'll acknowledge you. + Edward Lewis, Paul Vixie, Shane Kerr, Loganaden Velvindron. They + also vaguely remember discussing this with a number of people over + the years, but have forgotten who all they were -- if you were one of + them, and are not listed, please let us know and we'll acknowledge + you. I also want to thank the band "Infected Mushroom" for providing a good background soundtrack (and to see if I can get away with this!) Another author would like to thank the band "Mushroom Infectors". This was funny at the time we wrote it, but I cannot remember why... We would like to especially thank Peter van Dijk, who sent GitHub pull requests. 9. References @@ -455,30 +445,30 @@ Email: warren@kumari.net Evan Hunt ISC 950 Charter St Redwood City, CA 94063 US Email: each@isc.org + Roy Arends ICANN Email: roy.arends@icann.org - Wes Hardaker USC/ISI P.O. Box 382 - Davis, VA 95617 + Davis, CA 95617 US Email: ietf@hardakers.net David C Lawrence - Akamai Technologies - 150 Broadway - Cambridge, MA 02142-1054 + Oracle + Dyn + 150 Dow St + Manchester, NH 03101 US - Email: tale@akamai.com + Email: tale@dd.org