draft-ietf-dnsop-extended-error-16.original   draft-ietf-dnsop-extended-error-16.txt 
Network Working Group W. Kumari Internet Engineering Task Force (IETF) W. Kumari
Internet-Draft Google Request for Comments: 0000 Google
Intended status: Standards Track E. Hunt Category: Standards Track E. Hunt
Expires: November 6, 2020 ISC ISSN: 2070-1721 ISC
R. Arends R. Arends
ICANN ICANN
W. Hardaker W. Hardaker
USC/ISI USC/ISI
D. Lawrence D. Lawrence
Oracle + Dyn Oracle + Dyn
May 05, 2020 May 2020
Extended DNS Errors Extended DNS Errors
draft-ietf-dnsop-extended-error-16
Abstract Abstract
This document defines an extensible method to return additional This document defines an extensible method to return additional
information about the cause of DNS errors. Though created primarily information about the cause of DNS errors. Though created primarily
to extend SERVFAIL to provide additional information about the cause to extend SERVFAIL to provide additional information about the cause
of DNS and DNSSEC failures, the Extended DNS Errors option defined in of DNS and DNSSEC failures, the Extended DNS Errors option defined in
this document allows all response types to contain extended error this document allows all response types to contain extended error
information. Extended DNS Error information does not change the information. Extended DNS Error information does not change the
processing of RCODEs. processing of RCODEs.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This is an Internet Standards Track document.
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
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Internet Standards is available in Section 2 of RFC 7841.
This Internet-Draft will expire on November 6, 2020. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc0000.
Copyright Notice Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction and background . . . . . . . . . . . . . . . . . 3 1. Introduction and background
1.1. Requirements notation . . . . . . . . . . . . . . . . . . 3 1.1. Requirements notation
2. Extended DNS Error EDNS0 option format . . . . . . . . . . . 4 2. Extended DNS Error EDNS0 option format
3. Extended DNS Error Processing . . . . . . . . . . . . . . . . 5 3. Extended DNS Error Processing
4. Defined Extended DNS Errors . . . . . . . . . . . . . . . . . 5 4. Defined Extended DNS Errors
4.1. Extended DNS Error Code 0 - Other . . . . . . . . . . . . 6 4.1. Extended DNS Error Code 0 - Other
4.2. Extended DNS Error Code 1 - 4.2. Extended DNS Error Code 1 - Unsupported DNSKEY Algorithm
Unsupported DNSKEY Algorithm . . . . . . . . . . . . . . 6 4.3. Extended DNS Error Code 2 - Unsupported DS Digest Type
4.3. Extended DNS Error Code 2 - Unsupported DS 4.4. Extended DNS Error Code 3 - Stale Answer
Digest Type . . . . . . . . . . . . . . . . . . . . . . . 6 4.5. Extended DNS Error Code 4 - Forged Answer
4.4. Extended DNS Error Code 3 - Stale Answer . . . . . . . . 6 4.6. Extended DNS Error Code 5 - DNSSEC Indeterminate
4.5. Extended DNS Error Code 4 - Forged Answer . . . . . . . . 6 4.7. Extended DNS Error Code 6 - DNSSEC Bogus
4.6. Extended DNS Error Code 5 - DNSSEC Indeterminate . . . . 6 4.8. Extended DNS Error Code 7 - Signature Expired
4.7. Extended DNS Error Code 6 - DNSSEC Bogus . . . . . . . . 6 4.9. Extended DNS Error Code 8 - Signature Not Yet Valid
4.8. Extended DNS Error Code 7 - Signature Expired . . . . . . 6 4.10. Extended DNS Error Code 9 - DNSKEY Missing
4.9. Extended DNS Error Code 8 - Signature Not Yet Valid . . . 7 4.11. Extended DNS Error Code 10 - RRSIGs Missing
4.10. Extended DNS Error Code 9 - DNSKEY Missing . . . . . . . 7 4.12. Extended DNS Error Code 11 - No Zone Key Bit Set
4.11. Extended DNS Error Code 10 - RRSIGs Missing . . . . . . . 7 4.13. Extended DNS Error Code 12 - NSEC Missing
4.12. Extended DNS Error Code 11 - No Zone Key Bit Set . . . . 7 4.14. Extended DNS Error Code 13 - Cached Error
4.13. Extended DNS Error Code 12 - NSEC Missing . . . . . . . . 7 4.15. Extended DNS Error Code 14 - Not Ready
4.14. Extended DNS Error Code 13 - Cached Error . . . . . . . . 7 4.16. Extended DNS Error Code 15 - Blocked
4.15. Extended DNS Error Code 14 - Not Ready . . . . . . . . . 7 4.17. Extended DNS Error Code 16 - Censored
4.16. Extended DNS Error Code 15 - Blocked . . . . . . . . . . 7 4.18. Extended DNS Error Code 17 - Filtered
4.17. Extended DNS Error Code 16 - Censored . . . . . . . . . . 7 4.19. Extended DNS Error Code 18 - Prohibited
4.18. Extended DNS Error Code 17 - Filtered . . . . . . . . . . 8 4.20. Extended DNS Error Code 19 - Stale NXDOMAIN Answer
4.19. Extended DNS Error Code 18 - Prohibited . . . . . . . . . 8 4.21. Extended DNS Error Code 20 - Not Authoritative
4.20. Extended DNS Error Code 19 - Stale NXDOMAIN Answer . . . 8 4.22. Extended DNS Error Code 21 - Not Supported
4.21. Extended DNS Error Code 20 - Not Authoritative . . . . . 8 4.23. Extended DNS Error Code 22 - No Reachable Authority
4.22. Extended DNS Error Code 21 - Not Supported . . . . . . . 8 4.24. Extended DNS Error Code 23 - Network Error
4.23. Extended DNS Error Code 22 - No Reachable Authority . . . 8 4.25. Extended DNS Error Code 24 - Invalid Data
4.24. Extended DNS Error Code 23 - Network Error . . . . . . . 8 5. IANA Considerations
4.25. Extended DNS Error Code 24 - Invalid Data . . . . . . . . 9 5.1. A New Extended DNS Error Code EDNS Option
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 5.2. New Registry for Extended DNS Error Codes
5.1. A New Extended DNS Error Code EDNS Option . . . . . . . . 9 6. Security Considerations
5.2. New Registry for Extended DNS Error Codes . . . . . . . . 9 7. Acknowledgements
6. Security Considerations . . . . . . . . . . . . . . . . . . . 12 8. References
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12 8.1. Normative References
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 8.2. Informative References
8.1. Normative References . . . . . . . . . . . . . . . . . . 13 Authors' Addresses
8.2. Informative References . . . . . . . . . . . . . . . . . 13
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction and background 1. Introduction and background
There are many reasons that a DNS query may fail, some of them There are many reasons that a DNS query may fail, some of them
transient, some permanent; some can be resolved by querying another transient, some permanent; some can be resolved by querying another
server, some are likely best handled by stopping resolution. server, some are likely best handled by stopping resolution.
Unfortunately, the error signals that a DNS server can return are Unfortunately, the error signals that a DNS server can return are
very limited, and are not very expressive. This means that very limited, and are not very expressive. This means that
applications and resolvers often have to "guess" at what the issue is applications and resolvers often have to "guess" at what the issue is
- e.g. was the answer marked REFUSED because of a lame delegation, or - e.g. was the answer marked REFUSED because of a lame delegation, or
skipping to change at page 4, line 27 skipping to change at line 162
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
2: | OPTION-LENGTH | 2: | OPTION-LENGTH |
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
4: | INFO-CODE | 4: | INFO-CODE |
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
6: / EXTRA-TEXT ... / 6: / EXTRA-TEXT ... /
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+ +---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
Field definition details: Field definition details:
o OPTION-CODE, 2-octets/16-bits (defined in [RFC6891]]), for EDE is OPTION-CODE:
TBD. [RFC Editor: change TBD to the proper code once assigned by 2-octets/16-bits (defined in [RFC6891]]), for EDE is TBD. [RFC
IANA.] Editor: change TBD to the proper code once assigned by IANA.]
o OPTION-LENGTH, 2-octets/16-bits ((defined in [RFC6891]]) contains
the length of the payload (everything after OPTION-LENGTH) in OPTION-LENGTH:
octets and should be 2 plus the length of the EXTRA-TEXT field 2-octets/16-bits ((defined in [RFC6891]]) contains the length of
(which may be a zero-length string). the payload (everything after OPTION-LENGTH) in octets and should
o INFO-CODE, 16-bits, which is the principal contribution of this be 2 plus the length of the EXTRA-TEXT field (which may be a zero-
document. This 16-bit value, encoded in network (MSB) byte order, length string).
provides the additional context for the RESPONSE-CODE of the DNS
message. The INFO-CODE serves as an index into the "Extended DNS INFO-CODE:
Errors" registry defined and created in Section 5.2. 16-bits, which is the principal contribution of this document.
o EXTRA-TEXT, a variable length, UTF-8 encoded [RFC5198], text field This 16-bit value, encoded in network (MSB) byte order, provides
that may hold additional textual information. This information is the additional context for the RESPONSE-CODE of the DNS message.
intended for human consumption (not automated parsing). EDE text The INFO-CODE serves as an index into the "Extended DNS Errors"
may be null terminated but MUST NOT be assumed to be; the length registry defined and created in Section 5.2.
MUST be derived from the OPTION-LENGTH field. The EXTRA-TEXT
field may be zero octets in length, indicating that there is no EXTRA-TEXT:
EXTRA-TEXT included. Care should be taken not to include private a variable length, UTF-8 encoded [RFC5198], text field that may
information in the EXTRA-TEXT field that an observer would not hold additional textual information. This information is intended
otherwise have access to, such as account numbers. for human consumption (not automated parsing). EDE text may be
null terminated but MUST NOT be assumed to be; the length MUST be
derived from the OPTION-LENGTH field. The EXTRA-TEXT field may be
zero octets in length, indicating that there is no EXTRA-TEXT
included. Care should be taken not to include private information
in the EXTRA-TEXT field that an observer would not otherwise have
access to, such as account numbers.
The Extended DNS Error (EDE) option can be included in any response The Extended DNS Error (EDE) option can be included in any response
(SERVFAIL, NXDOMAIN, REFUSED, and even NOERROR, etc) to a query that (SERVFAIL, NXDOMAIN, REFUSED, and even NOERROR, etc) to a query that
includes OPT Pseudo-RR [RFC6891]. This document includes a set of includes OPT Pseudo-RR [RFC6891]. This document includes a set of
initial codepoints, but is extensible via the IANA registry defined initial codepoints, but is extensible via the IANA registry defined
and created in Section 5.2. and created in Section 5.2.
3. Extended DNS Error Processing 3. Extended DNS Error Processing
When the response grows beyond the requestor's UDP payload size When the response grows beyond the requestor's UDP payload size
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otherwise configured to support. Examples of this include its most otherwise configured to support. Examples of this include its most
recent zone being too old, or having expired. recent zone being too old, or having expired.
5. IANA Considerations 5. IANA Considerations
5.1. A New Extended DNS Error Code EDNS Option 5.1. A New Extended DNS Error Code EDNS Option
This document defines a new EDNS(0) option, entitled "Extended DNS This document defines a new EDNS(0) option, entitled "Extended DNS
Error", assigned a value of TBD from the "DNS EDNS0 Option Codes Error", assigned a value of TBD from the "DNS EDNS0 Option Codes
(OPT)" registry [to be removed upon publication: (OPT)" registry [to be removed upon publication:
[http://www.iana.org/assignments/dns-parameters/dns- http://www.iana.org/assignments/dns-parameters/dns-
parameters.xhtml#dns-parameters-11] parameters.xhtml#dns-parameters-11
Value Name Status Reference +-------+--------------------+----------+-------------------+
----- ---------------- ------ ------------------ | Value | Name | Status | Reference |
TBD Extended DNS Error Standard [ This document ] +=======+====================+==========+===================+
| TBD | Extended DNS Error | Standard | [ This document ] |
+-------+--------------------+----------+-------------------+
Table 1
5.2. New Registry for Extended DNS Error Codes 5.2. New Registry for Extended DNS Error Codes
IANA is requested to create and maintain a new registry table called IANA is requested to create and maintain a new registry table called
"Extended DNS Error Codes" on the "Domain Name System (DNS) "Extended DNS Error Codes" on the "Domain Name System (DNS)
Parameters" web page as follows: Parameters" web page as follows:
Registry Name: Extended DNS Error Codes Registry Name: Extended DNS Error Codes
Registration Procedures: Registration Procedures:
o 0 - 49151: First come, first served. * 0 - 49151: First come, first served.
o 49152 - 65535: Private use. * 49152 - 65535: Private use.
Reference: [this document] Reference: [this document]
The Extended DNS Error Codes registry is a table with three columns: The Extended DNS Error Codes registry is a table with three columns:
INFO-CODE, Purpose, and Reference. The initial contents is as below INFO-CODE, Purpose, and Reference. The initial contents is as below
with [this document] added to each reference given. with [this document] added to each reference given.
INFO-CODE: 0 +-----------+------------------------------+------------------------+
Purpose: Other Error | INFO-CODE | Purpose | Reference |
Reference: Section 4.1 +===========+==============================+========================+
| 0 | Other Error | Section 4.1 |
INFO-CODE: 1 +-----------+------------------------------+------------------------+
Purpose: Unsupported DNSKEY Algorithm | 1 | Unsupported DNSKEY Algorithm | Section 4.2 |
Reference: Section 4.2 +-----------+------------------------------+------------------------+
| 2 | Unsupported DS Digest Type | Section 4.3 |
INFO-CODE: 2 +-----------+------------------------------+------------------------+
Purpose: Unsupported DS Digest Type | 3 | Stale Answer | Section 4.4, |
Reference: Section 4.3 | | | [RFC8767] |
+-----------+------------------------------+------------------------+
INFO-CODE: 3 | 4 | Forged Answer | Section 4.5 |
Purpose: Stale Answer +-----------+------------------------------+------------------------+
Reference: Section 4.4, [RFC8767] | 5 | DNSSEC Indeterminate | Section 4.6 |
+-----------+------------------------------+------------------------+
INFO-CODE: 4 | 6 | DNSSEC Bogus | Section 4.7 |
Purpose: Forged Answer +-----------+------------------------------+------------------------+
Reference: Section 4.5 | 7 | Signature Expired | Section 4.8 |
+-----------+------------------------------+------------------------+
INFO-CODE: 5 | 8 | Signature Not Yet Valid | Section 4.9 |
Purpose: DNSSEC Indeterminate +-----------+------------------------------+------------------------+
Reference: Section 4.6 | 9 | DNSKEY Missing | Section 4.10 |
+-----------+------------------------------+------------------------+
INFO-CODE: 6 | 10 | RRSIGs Missing | Section 4.11 |
Purpose: DNSSEC Bogus +-----------+------------------------------+------------------------+
Reference: Section 4.7 | 11 | No Zone Key Bit Set | Section 4.12 |
+-----------+------------------------------+------------------------+
INFO-CODE: 7 | 12 | NSEC Missing | Section 4.13 |
Purpose: Signature Expired +-----------+------------------------------+------------------------+
Reference: Section 4.8 | 13 | Cached Error | Section 4.14 |
+-----------+------------------------------+------------------------+
INFO-CODE: 8 | 14 | Not Ready. | Section 4.15 |
Purpose: Signature Not Yet Valid +-----------+------------------------------+------------------------+
Reference: Section 4.9 | 15 | Blocked | Section 4.16 |
+-----------+------------------------------+------------------------+
INFO-CODE: 9 | 16 | Censored | Section 4.17 |
Purpose: DNSKEY Missing +-----------+------------------------------+------------------------+
Reference: Section 4.10 | 17 | Filtered | Section 4.18 |
+-----------+------------------------------+------------------------+
INFO-CODE: 10 | 18 | Prohibited | Section 4.19 |
Purpose: RRSIGs Missing +-----------+------------------------------+------------------------+
Reference: Section 4.11 | 19 | Stale NXDomain Answer | Section 4.20 |
+-----------+------------------------------+------------------------+
INFO-CODE: 11 | 20 | Not Authoritative | Section 4.21 |
Purpose: No Zone Key Bit Set +-----------+------------------------------+------------------------+
Reference: Section 4.12 | 21 | Not Supported | Section 4.22 |
+-----------+------------------------------+------------------------+
INFO-CODE: 12 | 22 | No Reachable Authority | Section 4.23 |
Purpose: NSEC Missing +-----------+------------------------------+------------------------+
Reference: Section 4.13 | 23 | Network Error | Section 4.24 |
+-----------+------------------------------+------------------------+
INFO-CODE: 13 | 24 | Invalid Data | Section 4.25 |
Purpose: Cached Error +-----------+------------------------------+------------------------+
Reference: Section 4.14 | 25 | Unassigned | Section 5.2 |
+-----------+------------------------------+------------------------+
INFO-CODE: 14
Purpose: Not Ready.
Reference: Section 4.15
INFO-CODE: 15
Purpose: Blocked
Reference: Section 4.16
INFO-CODE: 16
Purpose: Censored
Reference: Section 4.17
INFO-CODE: 17
Purpose: Filtered
Reference: Section 4.18
INFO-CODE: 18
Purpose: Prohibited
Reference: Section 4.19
INFO-CODE: 19
Purpose: Stale NXDomain Answer
Reference: Section 4.20
INFO-CODE: 20
Purpose: Not Authoritative
Reference: Section 4.21
INFO-CODE: 21
Purpose: Not Supported
Reference: Section 4.22
INFO-CODE: 22
Purpose: No Reachable Authority
Reference: Section 4.23
INFO-CODE: 23
Purpose: Network Error
Reference: Section 4.24
INFO-CODE: 24
Purpose: Invalid Data
Reference: Section 4.25
INFO-CODE: 25-65535 Table 2
Purpose: Unassigned
Reference: Section 5.2
6. Security Considerations 6. Security Considerations
Though DNSSEC continues to be deployed, unfortunately a significant Though DNSSEC continues to be deployed, unfortunately a significant
number of clients (~11% according to [GeoffValidation]) that receive number of clients (~11% according to [GeoffValidation]) that receive
a SERVFAIL from a validating resolver because of a DNSSEC validation a SERVFAIL from a validating resolver because of a DNSSEC validation
issue will simply ask the next (potentially non-validating) resolver issue will simply ask the next (potentially non-validating) resolver
in their list, and thus don't get the protections which DNSSEC should in their list, and thus don't get the protections which DNSSEC should
provide. provide.
skipping to change at page 12, line 38 skipping to change at line 515
By design, EDE potentially exposes additional information DNS By design, EDE potentially exposes additional information DNS
resolution processes that may leak information. An example of this resolution processes that may leak information. An example of this
is the Prohibited EDE code (18), which may leak the fact that the is the Prohibited EDE code (18), which may leak the fact that the
name is on a blacklist. name is on a blacklist.
7. Acknowledgements 7. Acknowledgements
The authors wish to thank Joe Abley, Mark Andrews, Tim April, The authors wish to thank Joe Abley, Mark Andrews, Tim April,
Vittorio Bertola, Stephane Bortzmeyer, Vladimir Cunat, Ralph Dolmans, Vittorio Bertola, Stephane Bortzmeyer, Vladimir Cunat, Ralph Dolmans,
Peter DeVries, Peter van Dijk, Mats Dufberg, Donald Eastlake, Bob Peter DeVries, Peter van Dijk,Mats Dufberg, Donald Eastlake, Bob
Harold, Paul Hoffman, Geoff Huston, Shane Kerr, Edward Lewis, Carlos Harold, Paul Hoffman, Geoff Huston, Shane Kerr, Edward Lewis, Carlos
M. Martinez, George Michelson, Eric Orth, Michael Sheldon, Puneet M. Martinez, George Michelson, Eric Orth, Michael Sheldon, Puneet
Sood, Petr Spacek, Ondrej Sury, John Todd, Loganaden Velvindron, and Sood, Petr Spacek, Ondrej Sury, John Todd, Loganaden Velvindron, and
Paul Vixie. They also vaguely remember discussing this with a number Paul Vixie. They also vaguely remember discussing this with a number
of people over the years, but have forgotten who all they were -- if 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 you were one of them, and are not listed, please let us know and
we'll acknowledge you. we'll acknowledge you.
One author also wants to thank the band "Infected Mushroom" for One author also wants to thank the band "Infected Mushroom" for
providing a good background soundtrack (and to see if he can get away providing a good background soundtrack (and to see if he can get away
skipping to change at page 14, line 23 skipping to change at line 596
[RFC8484] Hoffman, P. and P. McManus, "DNS Queries over HTTPS [RFC8484] Hoffman, P. and P. McManus, "DNS Queries over HTTPS
(DoH)", RFC 8484, DOI 10.17487/RFC8484, October 2018, (DoH)", RFC 8484, DOI 10.17487/RFC8484, October 2018,
<https://www.rfc-editor.org/info/rfc8484>. <https://www.rfc-editor.org/info/rfc8484>.
Authors' Addresses Authors' Addresses
Warren Kumari Warren Kumari
Google Google
1600 Amphitheatre Parkway 1600 Amphitheatre Parkway
Mountain View, CA 94043 Mountain View, CA 94043
US United States of America
Email: warren@kumari.net Email: warren@kumari.net
Evan Hunt Evan Hunt
ISC ISC
950 Charter St 950 Charter St
Redwood City, CA 94063 Redwood City, CA 94063
US United States of America
Email: each@isc.org Email: each@isc.org
Roy Arends Roy Arends
ICANN ICANN
Email: roy.arends@icann.org Email: roy.arends@icann.org
Wes Hardaker Wes Hardaker
USC/ISI USC/ISI
P.O. Box 382 P.O. Box 382
Davis, CA 95617 Davis, CA 95617
US United States of America
Email: ietf@hardakers.net Email: ietf@hardakers.net
David C Lawrence David C Lawrence
Oracle + Dyn Oracle + Dyn
150 Dow St 150 Dow St
Manchester, NH 03101 Manchester, NH 03101
US United States of America
Email: tale@dd.org Email: tale@dd.org
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