Internet DRAFT - draft-wessels-dns-zone-digest
draft-wessels-dns-zone-digest
Internet Engineering Task Force D. Wessels
Internet-Draft P. Barber
Intended status: Experimental M. Weinberg
Expires: August 17, 2019 Verisign
W. Kumari
Google
W. Hardaker
USC/ISI
February 13, 2019
Message Digest for DNS Zones
draft-wessels-dns-zone-digest-06
Abstract
This document describes an experimental protocol and new DNS Resource
Record that can be used to provide a message digest over DNS zone
data. The ZONEMD Resource Record conveys the message digest data in
the zone itself. When a zone publisher includes an ZONEMD record,
recipients can verify the zone contents for accuracy and
completeness. This provides assurance that received zone data
matches published data, regardless of how the zone data has been
transmitted and received.
ZONEMD is not designed to replace DNSSEC. Whereas DNSSEC protects
individual RRSets (DNS data with fine granularity), ZONEMD protects
protects a zone's data as a whole, whether consumed by authoritative
name servers, recursive name servers, or any other applications.
As specified at this time, ZONEMD is not designed for use in large,
dynamic zones due to the time and resources required for digest
calculation. The ZONEMD record described in this document includes
fields reserved for future work to support large, dynamic zones.
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
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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 August 17, 2019.
Copyright Notice
Copyright (c) 2019 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
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . 4
1.2. Design Overview . . . . . . . . . . . . . . . . . . . . . 5
1.3. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . 6
1.3.1. Root Zone . . . . . . . . . . . . . . . . . . . . . . 6
1.3.2. Providers, Secondaries, and Anycast . . . . . . . . . 6
1.3.3. Response Policy Zones . . . . . . . . . . . . . . . . 7
1.3.4. Centralized Zone Data Service . . . . . . . . . . . . 7
1.3.5. General Purpose Comparison Check . . . . . . . . . . 7
1.4. Requirements Language . . . . . . . . . . . . . . . . . . 7
2. The ZONEMD Resource Record . . . . . . . . . . . . . . . . . 7
2.1. ZONEMD RDATA Wire Format . . . . . . . . . . . . . . . . 8
2.1.1. The Serial Field . . . . . . . . . . . . . . . . . . 8
2.1.2. The Digest Type Field . . . . . . . . . . . . . . . . 8
2.1.3. The Reserved Field . . . . . . . . . . . . . . . . . 8
2.1.4. The Digest Field . . . . . . . . . . . . . . . . . . 8
2.2. ZONEMD Presentation Format . . . . . . . . . . . . . . . 9
2.3. ZONEMD Example . . . . . . . . . . . . . . . . . . . . . 9
3. Calculating the Digest . . . . . . . . . . . . . . . . . . . 9
3.1. Canonical Format and Ordering . . . . . . . . . . . . . . 9
3.1.1. Order of RRSets Having the Same Owner Name . . . . . 9
3.1.2. Duplicate RRs . . . . . . . . . . . . . . . . . . . . 10
3.2. Add ZONEMD Placeholder . . . . . . . . . . . . . . . . . 10
3.3. Optionally Sign the Zone . . . . . . . . . . . . . . . . 10
3.4. Calculate the Digest . . . . . . . . . . . . . . . . . . 10
3.4.1. Inclusion/Exclusion Rules . . . . . . . . . . . . . . 11
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3.5. Update ZONEMD RR . . . . . . . . . . . . . . . . . . . . 11
4. Verifying Zone Message Digest . . . . . . . . . . . . . . . . 11
5. Scope of Experimentation . . . . . . . . . . . . . . . . . . 13
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
6.1. ZONEMD RRtype . . . . . . . . . . . . . . . . . . . . . . 13
6.2. ZONEMD Digest Type . . . . . . . . . . . . . . . . . . . 14
7. Security Considerations . . . . . . . . . . . . . . . . . . . 14
7.1. Attacks Against the Zone Digest . . . . . . . . . . . . . 14
7.2. Attacks Utilizing the Zone Digest . . . . . . . . . . . . 14
8. Privacy Considerations . . . . . . . . . . . . . . . . . . . 15
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 15
10. Implementation Status . . . . . . . . . . . . . . . . . . . . 15
10.1. Authors' Implementation . . . . . . . . . . . . . . . . 15
10.2. Shane Kerr's Implementation . . . . . . . . . . . . . . 15
11. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 16
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 18
12.1. Normative References . . . . . . . . . . . . . . . . . . 18
12.2. Informative References . . . . . . . . . . . . . . . . . 19
Appendix A. Example Zones With Digests . . . . . . . . . . . . . 21
A.1. Simple EXAMPLE Zone . . . . . . . . . . . . . . . . . . . 21
A.2. Complex EXAMPLE Zone . . . . . . . . . . . . . . . . . . 21
A.3. The URI.ARPA Zone . . . . . . . . . . . . . . . . . . . . 22
A.4. The ROOT-SERVERS.NET Zone . . . . . . . . . . . . . . . . 25
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 27
1. Introduction
In the DNS, a zone is the collection of authoritative resource
records (RRs) sharing a common origin ([RFC7719]). Zones are often
stored as files on disk in the so-called master file format
[RFC1034]. Zones are generally distributed among name servers using
the AXFR [RFC5936], and IXFR [RFC1995] protocols. Zone files can
also be distributed outside of the DNS, with such protocols as FTP,
HTTP, rsync, and even via email. Currently there is no standard way
to verify the authenticity of a stand-alone zone.
This document introduces a new RR type that serves as a cryptographic
message digest of the data in a zone. It allows a receiver of the
zone to verify the zone's authenticity, especially when used in
combination with DNSSEC. This technique makes the message digest a
part of the zone itself, allowing verification the zone as a whole,
no matter how it is transmitted. Furthermore, the digest is based on
the wire format of zone data. Thus, it is independent of
presentation format, such as changes in whitespace, capitalization,
and comments.
DNSSEC provides three strong security guarantees relevant to this
protocol:
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1. whether or not to expect DNSSEC records in the zone,
2. whether or not to expect a ZONEMD record in a signed zone, and
3. whether or not the ZONEMD record has been altered since it was
signed.
This specification is OPTIONAL to implement by both publishers and
consumers of zone data.
1.1. Motivation
The motivation for this protocol enhancement is the desire for the
ability to verify the authenticity of a stand-alone zone, regardless
of how it is transmitted. A consumer of zone data should be able to
verify that the data is as-published by the zone operator.
One approach to preventing data tampering and corruption is to secure
the distribution channel. The DNS has a number of features that can
already be used for channel security. Perhaps the most widely used
is DNS transaction signatures (TSIG [RFC2845]). TSIG uses shared
secret keys and a message digest to protect individual query and
response messages. It is generally used to authenticate and validate
UPDATE [RFC2136], AXFR [RFC5936], and IXFR [RFC1995] messages.
DNS Request and Transaction Signatures (SIG(0) [RFC2931]) is another
protocol extension designed to authenticate individual DNS
transactions. Whereas SIG records were originally designed to cover
specific RR types, SIG(0) is used to sign an entire DNS message.
Unlike TSIG, SIG(0) uses public key cryptography rather than shared
secrets.
The Transport Layer Security protocol suite is also designed to
provide channel security. One can easily imagine the distribution of
zones over HTTPS-enabled web servers, as well as DNS-over-HTTPS
[dns-over-https], and perhaps even a future version of DNS-over-TLS
([RFC7858]).
Unfortunately, the protections provided by these channel security
techniques are (in practice) ephemeral and are not retained after the
data transfer is complete. They can ensure that the client receives
the data from the expected server, and that the data sent by the
server is not modified during transmission. However, they do not
guarantee that the server transmits the data as originally published,
and do not provide any methods to verify data that is read after
transmission is complete. For example, a name server loading saved
zone data upon restart cannot guarantee that the on-disk data has not
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been modified. For these reasons, it is preferable to secure the
data itself.
Why not simply rely on DNSSEC, which provides certain data security
guarantees? Certainly for zones that are signed, a recipient could
validate all of the signed RRSets. Additionally, denial-of-existence
records can prove that RRSets have not been added or removed.
However, not all RRSets in a zone are signed. The design of DNSSEC
stipulates that delegations (non-apex NS records) are not signed, and
neither are any glue records. Thus, changes to delegation and glue
records cannot be detected by DNSSEC alone. Furthermore, zones that
employ NSEC3 with opt-out are susceptible to the removal or addition
of names between the signed nodes. Whereas DNSSEC is primarily
designed to protect consumers of DNS response messages, this protocol
is designed to protect consumers of zones.
There are existing tools and protocols that provide data security,
such as OpenPGP [RFC4880] and S/MIME [RFC3851]. In fact, the
internic.net site publishes PGP signatures along side the root zone
and other files available there. However, this is a detached
signature with no strong association to the corresponding zone file
other than its timestamp. Non-detached signatures are, of course,
possible, but these necessarily change the format of the file being
distributed. That is, a zone signed with OpenPGP or S/MIME no longer
looks like a DNS zone and could not directly be loaded into a name
server. Once loaded the signature data is lost, so it does not
survive further propagation.
It seems the desire for data security in DNS zones was envisioned as
far back as 1997. [RFC2065] is an obsoleted specification of the
first generation DNSSEC Security Extensions. It describes a zone
transfer signature, aka AXFR SIG, which is similar to the technique
proposed by this document. That is, it proposes ordering all
(signed) RRSets in a zone, hashing their contents, and then signing
the zone hash. The AXFR SIG is described only for use during zone
transfers. It did not postulate the need to validate zone data
distributed outside of the DNS. Furthermore, its successor,
[RFC2535], omits the AXFR SIG, while at the same time introducing an
IXFR SIG.
1.2. Design Overview
This document introduces a new Resource Record type designed to
convey a message digest of the content of a zone. The digest is
calculated at the time of zone publication. Ideally the zone is
signed with DNSSEC to guarantee that any modifications of the digest
can be detected. The procedures for digest calculation and DNSSEC
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signing are similar (i.e., both require the same ordering of RRs) and
can be done in parallel.
The zone digest is designed to be used on zones that are relatively
stable and have infrequent updates. As currently specified, the
digest is re-calculated over the entire zone content each time. This
specification does not provide an efficient mechanism for incremental
updates of zone data. It does, however, reserve a field in the
ZONEMD record for future work to support incremental zone digest
algorithms (e.g. using Merkle trees).
It is expected that verification of a zone digest would be
implemented in name server software. That is, a name server can
verify the zone data it was given and refuse to serve a zone which
fails verification. For signed zones, the name server needs a trust
anchor to perform DNSSEC validation. For signed non-root zones, the
name server may need to send queries to validate a chain-of-trust.
Digest verification could also be performed externally.
1.3. Use Cases
1.3.1. Root Zone
The root zone [InterNIC] is one of the most widely distributed DNS
zone on the Internet, served by 930 separate instances [RootServers]
at the time of this writing. Additionally, many organizations
configure their own name servers to serve the root zone locally.
Reasons for doing so include privacy and reduced access time.
[RFC7706] describes one, but not the only, way to do this. As the
root zone spreads beyond its traditional deployment boundaries, the
need for verification of the completeness of the zone contents
becomes increasingly important.
1.3.2. Providers, Secondaries, and Anycast
Since its very early days, the developers of the DNS recognized the
importance of secondary name servers and service diversity. However,
they may not have anticipated the complexity of modern DNS service
provisioning which can include multiple third-party providers and
hundreds of anycast instances. Instead of a simple primary-to-
secondary zone distribution system, today it is possible to have
multiple levels, multiple parties, and multiple protocols involved in
the distribution of zone data. This complexity introduces new places
for problems to arise. The zone digest protects the integrity of
data that flows through such systems.
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1.3.3. Response Policy Zones
DNS Response Policy Zones is "a method of expressing DNS response
policy information inside specially constructed DNS zones..." [RPZ].
A number of companies provide RPZ feeds, which can be consumed by
name server and firewall products. Since these are zones, AXFR is
often, but not necessarily used for transmission. While RPZ zones
can certainly be signed with DNSSEC, the data is not queried
directly, and would not be subject to DNSSEC validation.
1.3.4. Centralized Zone Data Service
ICANN operates the Centralized Zone Data Service [CZDS], which is a
repository of top-level domain zone files. Users request access to
the system, and to individual zones, and are then able to download
zone data for certain uses. Adding a zone digest to these would
provide CZDS users with assurances that the data has not been
modified. Note that ZONEMD could be added to CZDS zone data
independently of the zone served by production name servers.
1.3.5. General Purpose Comparison Check
Since the zone digest does not depend on presentation format, it
could be used to compare multiple copies of a zone received from
different sources, or copies generated by different processes.
1.4. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
2. The ZONEMD Resource Record
This section describes the ZONEMD Resource Record, including its
fields, wire format, and presentation format. The Type value for the
ZONEMD RR is 63. The ZONEMD RR is class independent. The RDATA of
the resource record consists of four fields: Serial, Digest Type,
Reserved, and Digest.
FOR DISCUSSION: This document is currently written as though a zone
MUST NOT contain more than one ZONEMD RR. Having exactly one ZONEMD
record per zone simplifies this protocol and eliminates confusion
around downgrade attacks, at the expense of algorithm agility.
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2.1. ZONEMD RDATA Wire Format
The ZONEMD RDATA wire format is encoded as follows:
1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 3 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Serial |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Digest Type | Reserved | |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |
| Digest |
/ /
/ /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
2.1.1. The Serial Field
The Serial field is a 32-bit unsigned integer in network order. It
is equal to the serial number from the zone's SOA record ([RFC1035]
section 3.3.13) for which the message digest was generated.
The zone's serial number is included here in order to make DNS
response messages of type ZONEMD meaningful. Without the serial
number, a stand-alone ZONEMD digest has no association to any
particular instance of a zone.
2.1.2. The Digest Type Field
The Digest Type field is an 8-bit unsigned integer that identifies
the algorithm used to construct the digest.
At the time of this writing, SHA384, with value 1, is the only Digest
Type defined for ZONEMD records. The Digest Type registry is further
described in Section 6.
2.1.3. The Reserved Field
The Reserved field is an 8-bit unsigned integer, which is always set
to zero. This field is reserved for future work to support efficient
incremental updates.
2.1.4. The Digest Field
The Digest field is a variable-length sequence of octets containing
the message digest. Section 3 describes how to calculate the digest
for a zone. Section 4 describes how to use the digest to verify the
contents of a zone.
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2.2. ZONEMD Presentation Format
The presentation format of the RDATA portion is as follows:
The Serial field MUST be represented as an unsigned decimal integer.
The Digest Type field MUST be represented as an unsigned decimal
integer.
The Reserved field MUST be represented as an unsigned decimal integer
set to zero.
The Digest MUST be represented as a sequence of case-insensitive
hexadecimal digits. Whitespace is allowed within the hexadecimal
text.
2.3. ZONEMD Example
The following example shows a ZONEMD RR.
example.com. 86400 IN ZONEMD 2018031500 4 0 (
FEBE3D4CE2EC2FFA4BA99D46CD69D6D29711E55217057BEE
7EB1A7B641A47BA7FED2DD5B97AE499FAFA4F22C6BD647DE )
3. Calculating the Digest
3.1. Canonical Format and Ordering
Calculation of the zone digest REQUIRES the RRs in a zone to be
processed in a consistent format and ordering. Correct ordering of
the zone depends on (1) ordering of owner names in the zone, (2)
ordering of RRSets with the same owner name, and (3) ordering of RRs
within an RRSet.
This specification adopts DNSSEC's canonical ordering for names
(Section 6.1 of [RFC4034]), and canonical ordering for RRs within an
RRSet (Section 6.3 of [RFC4034]). It also adopts DNSSEC's canonical
RR form (Section 6.2 of [RFC4034]). However, since DNSSEC does not
define a canonical ordering for RRSets having the same owner name,
that ordering is defined here.
3.1.1. Order of RRSets Having the Same Owner Name
For the purposes of calculating the zone digest, RRSets having the
same owner name MUST be numerically ordered, in ascending order, by
their numeric RR TYPE.
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3.1.2. Duplicate RRs
As stated in Section 5 of [RFC2181], it is meaningless for a zone to
have multiple RRs with equal owner name, class, type, and RDATA. In
the interest of consistency and interoperability, such duplicate RRs
MUST NOT be included in the calculation of a zone digest.
3.2. Add ZONEMD Placeholder
In preparation for calculating the zone digest, any existing ZONEMD
record at the zone apex MUST first be deleted.
FOR DISCUSSION: Should non-apex ZONEMD records be allowed in a zone?
Or forbidden?
Prior to calculation of the digest, and prior to signing with DNSSEC,
a placeholder ZONEMD record MUST be added to the zone apex. This
serves two purposes: (1) it allows the digest to cover the Serial,
Digest Type, and Reserved field values, and (2) ensures that
appropriate denial-of-existence (NSEC, NSEC3) records are created if
the zone is signed with DNSSEC.
It is RECOMMENDED that the TTL of the ZONEMD record match the TTL of
the SOA.
In the placeholder record, the Serial field MUST be set to the
current SOA Serial. The Digest Type field MUST be set to the value
for the chosen digest algorithm. The Reserved field MUST be set to
zero. The Digest field MUST be set to all zeroes and of length
appropriate for the chosen digest algorithm.
3.3. Optionally Sign the Zone
Following addition of the placeholder record, the zone MAY be signed
with DNSSEC. Note that when the digest calculation is complete, and
the ZONEMD record is updated, the signature(s) for that record MUST
be recalculated and updated as well. Therefore, the signer is not
required to calculate a signature over the placeholder record at this
step in the process, but it is harmless to do so.
3.4. Calculate the Digest
The zone digest is calculated by concatenating the canonical on-the-
wire form (without name compression) of all RRs in the zone, in the
order described above, subject to the inclusion/exclusion rules
described below, and then applying the digest algorithm:
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digest = digest_algorithm( RR(1) | RR(2) | RR(3) | ... )
where "|" denotes concatenation, and
RR(i) = owner | type | class | TTL | RDATA length | RDATA
3.4.1. Inclusion/Exclusion Rules
When calculating the digest, the following inclusion/exclusion rules
apply:
o All records in the zone, including glue records, MUST be included.
o Occluded data ([RFC5936] Section 3.5) MUST be included.
o Duplicate RRs with equal owner, class, type, and RDATA MUST NOT be
included.
o The placeholder ZONEMD RR MUST be included.
o If the zone is signed, DNSSEC RRs MUST be included, except:
o The RRSIG covering ZONEMD MUST NOT be included.
3.5. Update ZONEMD RR
Once the zone digest has been calculated, its value is then copied to
the Digest field of the ZONEMD record.
If the zone is signed with DNSSEC, the appropriate RRSIG records
covering the ZONEMD record MUST then be added or updated. Because
the ZONEMD placeholder was added prior to signing, the zone will
already have the appropriate denial-of-existence (NSEC, NSEC3)
records.
Some implementations of incremental DNSSEC signing might update the
zone's serial number for each resigning. However, to preserve the
calculated digest, generation of the ZONEMD signature at this time
MUST NOT also result in a change of the SOA serial number.
4. Verifying Zone Message Digest
The recipient of a zone that has a message digest record can verify
the zone by calculating the digest as follows:
1. The verifier SHOULD first determine whether or not to expect
DNSSEC records in the zone. This can be done by examining
locally configured trust anchors, or querying for (and
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validating) DS RRs in the parent zone. For zones that are
provably unsigned, digest validation continues at step 4 below.
2. For zones that are provably signed, the existence of the apex
ZONEMD record MUST be verified. If the ZONEMD record provably
does not exist, digest verification cannot be done. If the
ZONEMD record does provably exist, but is not found in the zone,
digest verification MUST NOT be considered successful.
3. For zones that are provably signed, the SOA RR and ZONEMD RR
MUST have valid signatures, chaining up to a trust anchor. If
DNSSEC validation of the SOA or ZONEMD records fails, digest
verification MUST NOT be considered successful.
4. If the zone contains more than one apex ZONEMD RR, digest
verification MUST NOT be considered successful.
5. The SOA Serial field MUST exactly match the ZONEMD Serial field.
If the fields to not match, digest verification MUST NOT be
considered successful.
6. The ZONEMD Digest Type field MUST be checked. If the verifier
does not support the given digest type, it SHOULD report that
the zone digest could not be verified due to an unsupported
algorithm.
7. The Reserved field MUST be checked. If the Reserved field value
is not zero, verification MUST NOT be considered successful.
8. The received Digest Type and Digest values are copied to a
temporary location.
9. The ZONEMD RR's RDATA is reset to the placeholder values
described in Section 3.2.
10. The zone digest is computed over the zone data as described in
Section 3.4.
11. The calculated digest is compared to the received digest stored
in the temporary location. If the two digest values match,
verification is considered successful. Otherwise, verification
MUST NOT be considered successful.
12. The ZONEMD RR's RDATA is reset to the received Digest Type and
Digest stored in the temporary location. Thus, any downstream
clients can similarly verify the zone.
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5. Scope of Experimentation
This memo is published as an Experimental RFC. The purpose of the
experimental period is to provide the community time to analyze and
evaluate to the methods defined in this document, particularly with
regard to the wide variety of DNS zones in use on the Internet.
Additionally, the ZONEMD record defined in this document includes a
Reserved field in the form of an 8-bit integer. The authors have a
particular future use in mind for this field, namely to support
efficient digests in large, dynamic zones. We intend to conduct
future experiments using Merkle trees of varying depth. The choice
of tree depth can be encoded in this reserved field. We expect
values for tree depth to range from 0 to 10, requiring at most four
bits of this field. This leaves another four bits available for
other future uses, if absolutely necessary.
FOR DISCUSSION: The authors are willing to remove the Reserved field
from this specification if the working group would prefer it. It
would mean, however, that a future version of this protocol designed
to efficiently support large, dynamic zones would most likely require
a new RR type.
The duration of the experiment is expected to be no less than two
years from the publication of this document. If the experiment is
successful, it is expected that the findings of the experiment will
result in an updated document for Standards Track approval.
6. IANA Considerations
6.1. ZONEMD RRtype
This document defines a new DNS RR type, ZONEMD, whose value 63 has
been allocated by IANA from the "Resource Record (RR) TYPEs"
subregistry of the "Domain Name System (DNS) Parameters" registry:
Type: ZONEMD
Value: 63
Meaning: Message Digest Over Zone Data
Reference: This document
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6.2. ZONEMD Digest Type
This document asks IANA to create a new "ZONEMD Digest Types"
registry with initial contents as follows:
+-------+-------------+-----------+-----------+
| Value | Description | Status | Reference |
+-------+-------------+-----------+-----------+
| 1 | SHA384 | Mandatory | [RFC6605] |
+-------+-------------+-----------+-----------+
Table 1: ZONEMD Digest Types
7. Security Considerations
7.1. Attacks Against the Zone Digest
The zone digest allows the receiver to verify that the zone contents
haven't been modified since the zone was generated/published.
Verification is strongest when the zone is also signed with DNSSEC.
An attacker, whose goal is to modify zone content before it is used
by the victim, may consider a number of different approaches.
The attacker might perform a downgrade attack to an unsigned zone.
This is why Section 4 RECOMMENDS that the verifier determine whether
or not to expect DNSSEC signatures for the zone in step 1.
The attacker might perform a downgrade attack by removing the ZONEMD
record. This is why Section 4 REQUIRES that the verifier checks
DNSSEC denial-of-existence proofs in step 2.
The attacker might alter the Digest Type or Digest fields of the
ZONEMD record. Such modifications are detectable only with DNSSEC
validation.
7.2. Attacks Utilizing the Zone Digest
Nothing in this specification prevents clients from making, and
servers from responding to, ZONEMD queries. One might consider how
well ZONEMD responses could be used in a distributed denial-of-
service amplification attack.
The ZONEMD RR is moderately sized, much like the DS RR. A single
ZONEMD RR contributes approximately 40 to 65 octets to a DNS
response, for currently defined digest types. Certainly other query
types result in larger amplification effects (i.e., DNSKEY).
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8. Privacy Considerations
This specification has no impacts on user privacy.
9. Acknowledgments
The authors wish to thank David Blacka, Scott Hollenbeck, and Rick
Wilhelm for providing feedback on early drafts of this document.
Additionally, they thank Joe Abley, Mark Andrews, Olafur Gudmundsson,
Paul Hoffman, Evan Hunt, Shumon Huque, Tatuya Jinmei, Burt Kaliski,
Shane Kerr, Matt Larson, John Levine, Ed Lewis, Mukund Sivaraman,
Petr Spacek, Ondrej Sury, Florian Weimer, Tim Wicinksi, Paul Wouters,
and other members of the dnsop working group for their input.
10. Implementation Status
10.1. Authors' Implementation
The authors have an open source implementation in C, using the ldns
library [ldns-zone-digest]. This implementation is able to perform
the following functions:
o Read an input zone and output a zone with the ZONEMD placeholder.
o Compute zone digest over signed zone and update the ZONEMD record.
o Re-compute DNSSEC signature over the ZONEMD record.
o Verify the zone digest from an input zone.
This implementation does not:
o Perform DNSSEC validation of the ZONEMD record.
o Support the Gost digest algorithm.
o Output the ZONEMD record in its defined presentation format.
10.2. Shane Kerr's Implementation
Shane Kerr wrote an implementation of this specification during the
IETF 102 hackathon [ZoneDigestHackathon]. This implementation is in
Python and is able to perform the following functions:
o Read an input zone and a output zone with ZONEMD record.
o Verify the zone digest from an input zone.
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o Output the ZONEMD record in its defined presentation format.
o Generate Gost digests.
This implementation does not:
o Re-compute DNSSEC signature over the ZONEMD record.
o Perform DNSSEC validation of the ZONEMD record.
11. Change Log
RFC Editor: Please remove this section.
This section lists substantial changes to the document as it is being
worked on.
From -00 to -01:
o Removed requirement to sort by RR CLASS.
o Added Kumari and Hardaker as coauthors.
o Added Change Log section.
o Minor clarifications and grammatical edits.
From -01 to -02:
o Emphasize desire for data security over channel security.
o Expanded motivation into its own subsection.
o Removed discussion topic whether or not to include serial in
ZONEMD.
o Clarified that a zone's NS records always sort before the SOA
record.
o Clarified that all records in the zone must are digested, except
as specified in the exclusion rules.
o Added for discussion out-of-zone and occluded records.
o Clarified that update of ZONEMD signature must not cause a serial
number change.
o Added persons to acknowledgments.
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From -02 to -03:
o Added recommendation to set ZONEMD TTL to SOA TTL.
o Clarified that digest input uses uncompressed names.
o Updated Implementations section.
o Changed intended status from Standards Track to Experimental and
added Scope of Experiment section.
o Updated Motivation, Introduction, and Design Overview sections in
response to working group discussion.
o Gave ZONEMD digest types their own status, separate from DS digest
types. Request IANA to create a registry.
o Added Reserved field for future work supporting dynamic updates.
o Be more rigorous about having just ONE ZONEMD record in the zone.
o Expanded use cases.
From -03 to -04:
o Added an appendix with example zones and digests.
o Clarified that only apex ZONEMD RRs shall be processed.
From -04 to -05:
o Made SHA384 the only supported ZONEMD digest type.
o Disassociated ZONEMD digest types from DS digest types.
o Updates to Introduction based on list feedback.
o Changed "zone file" to "zone" everywhere.
o Restored text about why ZONEMD has a Serial field.
o Clarified ordering of RRSets having same owner to be numerically
ascending.
o Clarified that all duplicate RRs (not just SOA) must be suppressed
in digest calculation.
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o Clarified that the Reserved field must be set to zero and checked
for zero in verification.
o Clarified that occluded data must be included.
o Clarified procedure for verification, using temporary location for
received digest.
o Explained why Reserved field is 8-bits.
o IANA Considerations section now more specific.
o Added complex zone to examples.
o
From -05 to -06:
o RR type code 63 was assigned to ZONEMD by IANA.
12. References
12.1. Normative References
[RFC1034] Mockapetris, P., "Domain names - concepts and facilities",
STD 13, RFC 1034, DOI 10.17487/RFC1034, November 1987,
<https://www.rfc-editor.org/info/rfc1034>.
[RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, DOI 10.17487/RFC1035,
November 1987, <https://www.rfc-editor.org/info/rfc1035>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC2181] Elz, R. and R. Bush, "Clarifications to the DNS
Specification", RFC 2181, DOI 10.17487/RFC2181, July 1997,
<https://www.rfc-editor.org/info/rfc2181>.
[RFC4034] Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "Resource Records for the DNS Security Extensions",
RFC 4034, DOI 10.17487/RFC4034, March 2005,
<https://www.rfc-editor.org/info/rfc4034>.
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[RFC6605] Hoffman, P. and W. Wijngaards, "Elliptic Curve Digital
Signature Algorithm (DSA) for DNSSEC", RFC 6605,
DOI 10.17487/RFC6605, April 2012,
<https://www.rfc-editor.org/info/rfc6605>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
12.2. Informative References
[CZDS] Internet Corporation for Assigned Names and Numbers,
"Centralized Zone Data Service", October 2018,
<https://czds.icann.org/>.
[dns-over-https]
Hoffman, P. and P. McManus, "DNS Queries over HTTPS
(DoH)", draft-ietf-doh-dns-over-https-12 (work in
progress), June 2018, <https://tools.ietf.org/html/
draft-ietf-doh-dns-over-https-12>.
[InterNIC]
ICANN, "InterNIC FTP site", May 2018,
<ftp://ftp.internic.net/domain/>.
[ldns-zone-digest]
Verisign, "Implementation of Message Digests for DNS Zones
using the ldns library", July 2018,
<https://github.com/verisign/ldns-zone-digest>.
[RFC1995] Ohta, M., "Incremental Zone Transfer in DNS", RFC 1995,
DOI 10.17487/RFC1995, August 1996,
<https://www.rfc-editor.org/info/rfc1995>.
[RFC2065] Eastlake 3rd, D. and C. Kaufman, "Domain Name System
Security Extensions", RFC 2065, DOI 10.17487/RFC2065,
January 1997, <https://www.rfc-editor.org/info/rfc2065>.
[RFC2136] Vixie, P., Ed., Thomson, S., Rekhter, Y., and J. Bound,
"Dynamic Updates in the Domain Name System (DNS UPDATE)",
RFC 2136, DOI 10.17487/RFC2136, April 1997,
<https://www.rfc-editor.org/info/rfc2136>.
[RFC2535] Eastlake 3rd, D., "Domain Name System Security
Extensions", RFC 2535, DOI 10.17487/RFC2535, March 1999,
<https://www.rfc-editor.org/info/rfc2535>.
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[RFC2845] Vixie, P., Gudmundsson, O., Eastlake 3rd, D., and B.
Wellington, "Secret Key Transaction Authentication for DNS
(TSIG)", RFC 2845, DOI 10.17487/RFC2845, May 2000,
<https://www.rfc-editor.org/info/rfc2845>.
[RFC2931] Eastlake 3rd, D., "DNS Request and Transaction Signatures
( SIG(0)s )", RFC 2931, DOI 10.17487/RFC2931, September
2000, <https://www.rfc-editor.org/info/rfc2931>.
[RFC3851] Ramsdell, B., Ed., "Secure/Multipurpose Internet Mail
Extensions (S/MIME) Version 3.1 Message Specification",
RFC 3851, DOI 10.17487/RFC3851, July 2004,
<https://www.rfc-editor.org/info/rfc3851>.
[RFC4880] Callas, J., Donnerhacke, L., Finney, H., Shaw, D., and R.
Thayer, "OpenPGP Message Format", RFC 4880,
DOI 10.17487/RFC4880, November 2007,
<https://www.rfc-editor.org/info/rfc4880>.
[RFC5936] Lewis, E. and A. Hoenes, Ed., "DNS Zone Transfer Protocol
(AXFR)", RFC 5936, DOI 10.17487/RFC5936, June 2010,
<https://www.rfc-editor.org/info/rfc5936>.
[RFC7706] Kumari, W. and P. Hoffman, "Decreasing Access Time to Root
Servers by Running One on Loopback", RFC 7706,
DOI 10.17487/RFC7706, November 2015,
<https://www.rfc-editor.org/info/rfc7706>.
[RFC7719] Hoffman, P., Sullivan, A., and K. Fujiwara, "DNS
Terminology", RFC 7719, DOI 10.17487/RFC7719, December
2015, <https://www.rfc-editor.org/info/rfc7719>.
[RFC7858] Hu, Z., Zhu, L., Heidemann, J., Mankin, A., Wessels, D.,
and P. Hoffman, "Specification for DNS over Transport
Layer Security (TLS)", RFC 7858, DOI 10.17487/RFC7858, May
2016, <https://www.rfc-editor.org/info/rfc7858>.
[RootServers]
Root Server Operators, "Root Server Technical Operations",
July 2018, <https://www.root-servers.org/>.
[RPZ] Vixie, P. and V. Schryver, "DNS Response Policy Zones
(RPZ)", draft-vixie-dnsop-dns-rpz-00 (work in progress),
June 2018, <https://tools.ietf.org/html/
draft-vixie-dnsop-dns-rpz-00>.
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[ZoneDigestHackathon]
Kerr, S., "Prototype implementation of ZONEMD for the IETF
102 hackathon in Python", July 2018,
<https://github.com/shane-kerr/ZoneDigestHackathon>.
Appendix A. Example Zones With Digests
This appendex contains example zones with accurate ZONEMD records.
These can be used to verify an implementation of the zone digest
protocol.
A.1. Simple EXAMPLE Zone
Here, the EXAMPLE zone contains an SOA record, NS and glue records,
and a ZONEMD record.
example. 86400 IN SOA ns1 admin 2018031900 (
1800 900 604800 86400 )
86400 IN NS ns1
86400 IN NS ns2
86400 IN ZONEMD 2018031900 1 0 (
f32765ce15c50477
42a08be15d9a0efb
749417eaadcfa28b
1bf751b6bc49f9be
a615c4a386cfd6a5
d85e2d2182691249 )
ns1 3600 IN A 127.0.0.1
ns2 3600 IN AAAA ::1
A.2. Complex EXAMPLE Zone
Here, the EXAMPLE zone contains duplicate RRs, and an occluded RR,
and one out-of-zone RR.
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example. 86400 IN SOA ns1 admin 2018031900 (
1800 900 604800 86400 )
86400 IN NS ns1
86400 IN NS ns2
86400 IN ZONEMD 2018031900 1 0 (
686a6d74d5638612
64ea4e6cc12c22d1
7ebc529791d393bd
e164a45390f714e9
9ede0d05a5644573
da4bbcc83744acf2 )
ns1 3600 IN A 127.0.0.1
ns2 3600 IN AAAA ::1
occluded.sub 7200 IN TXT "I'm occluded but must be digested"
sub 7200 IN NS ns1
duplicate 300 IN TXT "I must be digested just once"
duplicate 300 IN TXT "I must be digested just once"
foo.test. 555 IN TXT "out-of-zone data must be excluded"
A.3. The URI.ARPA Zone
The URI.ARPA zone retreived 2018-10-21.
; <<>> DiG 9.9.4 <<>> @lax.xfr.dns.icann.org uri.arpa axfr
; (2 servers found)
;; global options: +cmd
uri.arpa. 3600 IN SOA sns.dns.icann.org. (
noc.dns.icann.org. 2018100702 10800 3600 1209600 3600 )
uri.arpa. 3600 IN RRSIG NSEC 8 2 3600 (
20181028142623 20181007205525 47155 uri.arpa.
eEC4w/oXLR1Epwgv4MBiDtSBsXhqrJVvJWUpbX8XpetAvD35bxwNCUTi
/pAJVUXefegWeiriD2rkTgCBCMmn7YQIm3gdR+HjY/+o3BXNQnz97f+e
HAE9EDDzoNVfL1PyV/2fde9tDeUuAGVVwmD399NGq9jWYMRpyri2kysr q/g= )
uri.arpa. 86400 IN RRSIG NS 8 2 86400 (
20181028172020 20181007175821 47155 uri.arpa.
ATyV2A2A8ZoggC+68u4GuP5MOUuR+2rr3eWOkEU55zAHld/7FiBxl4ln
4byJYy7NudUwlMOEXajqFZE7DVl8PpcvrP3HeeGaVzKqaWj+aus0jbKF
Bsvs2b1qDZemBfkz/IfAhUTJKnto0vSUicJKfItu0GjyYNJCz2CqEuGD Wxc= )
uri.arpa. 600 IN RRSIG MX 8 2 600 (
20181028170556 20181007175821 47155 uri.arpa.
e7/r3KXDohX1lyVavetFFObp8fB8aXT76HnN9KCQDxSnSghNM83UQV0t
lTtD8JVeN1mCvcNFZpagwIgB7XhTtm6Beur/m5ES+4uSnVeS6Q66HBZK
A3mR95IpevuVIZvvJ+GcCAQpBo6KRODYvJ/c/ZG6sfYWkZ7qg/Em5/+3 4UI= )
uri.arpa. 3600 IN RRSIG DNSKEY 8 2 3600 (
20181028152832 20181007175821 15796 uri.arpa.
nzpbnh0OqsgBBP8St28pLvPEQ3wZAUdEBuUwil+rtjjWlYYiqjPxZ286
XF4Rq1usfV5x71jZz5IqswOaQgia91ylodFpLuXD6FTGs2nXGhNKkg1V
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chHgtwj70mXU72GefVgo8TxrFYzxuEFP5ZTP92t97FVWVVyyFd86sbbR
6DZj3uA2wEvqBVLECgJLrMQ9Yy7MueJl3UA4h4E6zO2JY9Yp0W9woq0B
dqkkwYTwzogyYffPmGAJG91RJ2h6cHtFjEZe2MnaY2glqniZ0WT9vXXd
uFPm0KD9U77Ac+ZtctAF9tsZwSdAoL365E2L1usZbA+K0BnPPqGFJRJk
5R0A1w== )
uri.arpa. 3600 IN RRSIG DNSKEY 8 2 3600 (
20181028152832 20181007175821 55480 uri.arpa.
lWtQV/5szQjkXmbcD47/+rOW8kJPksRFHlzxxmzt906+DBYyfrH6uq5X
nHvrUlQO6M12uhqDeL+bDFVgqSpNy+42/OaZvaK3J8EzPZVBHPJykKMV
63T83aAiJrAyHzOaEdmzLCpalqcEE2ImzlLHSafManRfJL8Yuv+JDZFj
2WDWfEcUuwkmIZWX11zxp+DxwzyUlRl7x4+ok5iKZWIg5UnBAf6B8T75
WnXzlhCw3F2pXI0a5LYg71L3Tp/xhjN6Yy9jGlIRf5BjB59X2zra3a2R
PkI09SSnuEwHyF1mDaV5BmQrLGRnCjvwXA7ho2m+vv4SP5dUdXf+GTeA
1HeBfw== )
uri.arpa. 3600 IN RRSIG SOA 8 2 3600 (
20181029114753 20181008222815 47155 uri.arpa.
qn8yBNoHDjGdT79U2Wu9IIahoS0YPOgYP8lG+qwPcrZ1BwGiHywuoUa2
Mx6BWZlg+HDyaxj2iOmox+IIqoUHhXUbO7IUkJFlgrOKCgAR2twDHrXu
9BUQHy9SoV16wYm3kBTEPyxW5FFm8vcdnKAF7sxSY8BbaYNpRIEjDx4A JUc= )
uri.arpa. 3600 IN NSEC ftp.uri.arpa. NS SOA (
MX RRSIG NSEC DNSKEY )
uri.arpa. 86400 IN NS a.iana-servers.net.
uri.arpa. 86400 IN NS b.iana-servers.net.
uri.arpa. 86400 IN NS c.iana-servers.net.
uri.arpa. 86400 IN NS ns2.lacnic.net.
uri.arpa. 86400 IN NS sec3.apnic.net.
uri.arpa. 600 IN MX 10 pechora.icann.org.
uri.arpa. 3600 IN DNSKEY 256 3 8 (
AwEAAcBi7tSart2J599zbYWspMNGN70IBWb4ziqyQYH9MTB/VCz6WyUK
uXunwiJJbbQ3bcLqTLWEw134B6cTMHrZpjTAb5WAwg4XcWUu8mdcPTiL
Bl6qVRlRD0WiFCTzuYUfkwsh1Rbr7rvrxSQhF5rh71zSpwV5jjjp65Wx
SdJjlH0B )
uri.arpa. 3600 IN DNSKEY 257 3 8 (
AwEAAbNVv6ulgRdO31MtAehz7j3ALRjwZglWesnzvllQl/+hBRZr9QoY
cO2I+DkO4Q1NKxox4DUIxj8SxPO3GwDuOFR9q2/CFi2O0mZjafbdYtWc
3zSdBbi3q0cwCIx7GuG9eqlL+pg7mdk9dgdNZfHwB0LnqTD8ebLPsrO/
Id7kBaiqYOfMlZnh2fp+2h6OOJZHtY0DK1UlssyB5PKsE0tVzo5s6zo9
iXKe5u+8WTMaGDY49vG80JPAKE7ezMiH/NZcUMiE0PRZ8D3foq2dYuS5
ym+vA83Z7v8A+Rwh4UGnjxKB8zmr803V0ASAmHz/gwH5Vb0nH+LObwFt
l3wpbp+Wpm8= )
uri.arpa. 3600 IN DNSKEY 257 3 8 (
AwEAAbwnFTakCvaUKsXji4mgmxZUJi1IygbnGahbkmFEa0L16J+TchKR
wcgzVfsxUGa2MmeA4hgkAooC3uy+tTmoMsgy8uq/JAj24DjiHzd46LfD
FK/qMidVqFpYSHeq2Vv5ojkuIsx4oe4KsafGWYNOczKZgH5loGjN2aJG
mrIm++XCphOskgCsQYl65MIzuXffzJyxlAuts+ecAIiVeqRaqQfr8LRU
7wIsLxinXirprtQrbor+EtvlHp9qXE6ARTZDzf4jvsNpKvLFZtmxzFf3
e/UJz5eHjpwDSiZL7xE8aE1o1nGfPtJx9ZnB3bapltaJ5wY+5XOCKgY0
xmJVvNQlwdE= )
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ftp.uri.arpa. 3600 IN RRSIG NSEC 8 3 3600 (
20181028080856 20181007175821 47155 uri.arpa.
HClGAqPxzkYkAT7Q/QNtQeB6YrkP6EPOef+9Qo5/2zngwAewXEAQiyF9
jD1USJiroM11QqBS3v3aIdW/LXORs4Ez3hLcKNO1cKHsOuWAqzmE+BPP
Arfh8N95jqh/q6vpaB9UtMkQ53tM2fYU1GszOLN0knxbHgDHAh2axMGH lqM= )
ftp.uri.arpa. 604800 IN RRSIG NAPTR 8 3 604800 (
20181028103644 20181007205525 47155 uri.arpa.
WoLi+vZzkxaoLr2IGZnwkRvcDf6KxiWQd1WZP/U+AWnV+7MiqsWPZaf0
9toRErerGoFOiOASNxZjBGJrRgjmavOM9U+LZSconP9zrNFd4dIu6kp5
YxlQJ0uHOvx1ZHFCj6lAt1ACUIw04ZhMydTmi27c8MzEOMepvn7iH7r7 k7k= )
ftp.uri.arpa. 3600 IN NSEC http.uri.arpa. NAPTR (
RRSIG NSEC )
ftp.uri.arpa. 604800 IN NAPTR 0 0 "" "" (
"!^ftp://([^:/?#]*).*$!\\1!i" . )
http.uri.arpa. 3600 IN RRSIG NSEC 8 3 3600 (
20181029010647 20181007175821 47155 uri.arpa.
U03NntQ73LHWpfLmUK8nMsqkwVsOGW2KdsyuHYAjqQSZvKbtmbv7HBmE
H1+Ii3Z+wtfdMZBy5aC/6sHdx69BfZJs16xumycMlAy6325DKTQbIMN+
ift9GrKBC7cgCd2msF/uzSrYxxg4MJQzBPvlkwXnY3b7eJSlIXisBIn7 3b8= )
http.uri.arpa. 604800 IN RRSIG NAPTR 8 3 604800 (
20181029011815 20181007205525 47155 uri.arpa.
T7mRrdag+WSmG+n22mtBSQ/0Y3v+rdDnfQV90LN5Fq32N5K2iYFajF7F
Tp56oOznytfcL4fHrqOE0wRc9NWOCCUec9C7Wa1gJQcllEvgoAM+L6f0
RsEjWq6+9jvlLKMXQv0xQuMX17338uoD/xiAFQSnDbiQKxwWMqVAimv5 7Zs= )
http.uri.arpa. 3600 IN NSEC mailto.uri.arpa. NAPTR (
RRSIG NSEC )
http.uri.arpa. 604800 IN NAPTR 0 0 "" "" (
"!^http://([^:/?#]*).*$!\\1!i" . )
mailto.uri.arpa. 3600 IN RRSIG NSEC 8 3 3600 (
20181028110727 20181007175821 47155 uri.arpa.
GvxzVL85rEukwGqtuLxek9ipwjBMfTOFIEyJ7afC8HxVMs6mfFa/nEM/
IdFvvFg+lcYoJSQYuSAVYFl3xPbgrxVSLK125QutCFMdC/YjuZEnq5cl
fQciMRD7R3+znZfm8d8u/snLV9w4D+lTBZrJJUBe1Efc8vum5vvV7819 ZoY= )
mailto.uri.arpa. 604800 IN RRSIG NAPTR 8 3 604800 (
20181028141825 20181007205525 47155 uri.arpa.
MaADUgc3fc5v++M0YmqjGk3jBdfIA5RuP62hUSlPsFZO4k37erjIGCfF
j+g84yc+QgbSde0PQHszl9fE/+SU5ZXiS9YdcbzSZxp2erFpZOTchrpg
916T4vx6i59scodjb0l6bDyZ+mtIPrc1w6b4hUyOUTsDQoAJYxdfEuMg Vy4= )
mailto.uri.arpa. 3600 IN NSEC urn.uri.arpa. NAPTR (
RRSIG NSEC )
mailto.uri.arpa. 604800 IN NAPTR 0 0 "" "" (
"!^mailto:(.*)@(.*)$!\\2!i" . )
urn.uri.arpa. 3600 IN RRSIG NSEC 8 3 3600 (
20181028123243 20181007175821 47155 uri.arpa.
Hgsw4Deops1O8uWyELGe6hpR/OEqCnTHvahlwiQkHhO5CSEQrbhmFAWe
UOkmGAdTEYrSz+skLRQuITRMwzyFf4oUkZihGyhZyzHbcxWfuDc/Pd/9
DSl56gdeBwy1evn5wBTms8yWQVkNtphbJH395gRqZuaJs3LD/qTyJ5Dp LvA= )
urn.uri.arpa. 604800 IN RRSIG NAPTR 8 3 604800 (
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Internet-Draft DNS Zone Digest February 2019
20181029071816 20181007205525 47155 uri.arpa.
ALIZD0vBqAQQt40GQ0Efaj8OCyE9xSRJRdyvyn/H/wZVXFRFKrQYrLAS
D/K7q6CMTOxTRCu2J8yes63WJiaJEdnh+dscXzZkmOg4n5PsgZbkvUSW
BiGtxvz5jNncM0xVbkjbtByrvJQAO1cU1mnlDKe1FmVB1uLpVdA9Ib4J hMU= )
urn.uri.arpa. 3600 IN NSEC uri.arpa. NAPTR RRSIG (
NSEC )
urn.uri.arpa. 604800 IN NAPTR 0 0 "" "" (
"/urn:([^:]+)/\\1/i" . )
uri.arpa. 3600 IN SOA sns.dns.icann.org. (
noc.dns.icann.org. 2018100702 10800 3600 1209600 3600 )
;; Query time: 66 msec
;; SERVER: 192.0.32.132#53(192.0.32.132)
;; WHEN: Sun Oct 21 20:39:28 UTC 2018
;; XFR size: 34 records (messages 1, bytes 3941)
uri.arpa. 3600 IN ZONEMD 2018100702 1 0 (
80af7afd9540ff2c4c559f0d2b83393386304e093e0e66787378b2
a578297b49b4dccb422bce2c300bb92b354575283a )
A.4. The ROOT-SERVERS.NET Zone
The ROOT-SERVERS.NET zone retreived 2018-10-21.
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Internet-Draft DNS Zone Digest February 2019
root-servers.net. 3600000 IN SOA a.root-servers.net. (
nstld.verisign-grs.com. 2018091100 14400 7200 1209600 3600000 )
root-servers.net. 3600000 IN NS a.root-servers.net.
root-servers.net. 3600000 IN NS b.root-servers.net.
root-servers.net. 3600000 IN NS c.root-servers.net.
root-servers.net. 3600000 IN NS d.root-servers.net.
root-servers.net. 3600000 IN NS e.root-servers.net.
root-servers.net. 3600000 IN NS f.root-servers.net.
root-servers.net. 3600000 IN NS g.root-servers.net.
root-servers.net. 3600000 IN NS h.root-servers.net.
root-servers.net. 3600000 IN NS i.root-servers.net.
root-servers.net. 3600000 IN NS j.root-servers.net.
root-servers.net. 3600000 IN NS k.root-servers.net.
root-servers.net. 3600000 IN NS l.root-servers.net.
root-servers.net. 3600000 IN NS m.root-servers.net.
a.root-servers.net. 3600000 IN AAAA 2001:503:ba3e::2:30
a.root-servers.net. 3600000 IN A 198.41.0.4
b.root-servers.net. 3600000 IN MX 20 mail.isi.edu.
b.root-servers.net. 3600000 IN AAAA 2001:500:200::b
b.root-servers.net. 3600000 IN A 199.9.14.201
c.root-servers.net. 3600000 IN AAAA 2001:500:2::c
c.root-servers.net. 3600000 IN A 192.33.4.12
d.root-servers.net. 3600000 IN AAAA 2001:500:2d::d
d.root-servers.net. 3600000 IN A 199.7.91.13
e.root-servers.net. 3600000 IN AAAA 2001:500:a8::e
e.root-servers.net. 3600000 IN A 192.203.230.10
f.root-servers.net. 3600000 IN AAAA 2001:500:2f::f
f.root-servers.net. 3600000 IN A 192.5.5.241
g.root-servers.net. 3600000 IN AAAA 2001:500:12::d0d
g.root-servers.net. 3600000 IN A 192.112.36.4
h.root-servers.net. 3600000 IN AAAA 2001:500:1::53
h.root-servers.net. 3600000 IN A 198.97.190.53
i.root-servers.net. 3600000 IN MX 10 mx.i.root-servers.org.
i.root-servers.net. 3600000 IN AAAA 2001:7fe::53
i.root-servers.net. 3600000 IN A 192.36.148.17
j.root-servers.net. 3600000 IN AAAA 2001:503:c27::2:30
j.root-servers.net. 3600000 IN A 192.58.128.30
k.root-servers.net. 3600000 IN AAAA 2001:7fd::1
k.root-servers.net. 3600000 IN A 193.0.14.129
l.root-servers.net. 3600000 IN AAAA 2001:500:9f::42
l.root-servers.net. 3600000 IN A 199.7.83.42
m.root-servers.net. 3600000 IN AAAA 2001:dc3::35
m.root-servers.net. 3600000 IN A 202.12.27.33
root-servers.net. 3600000 IN SOA a.root-servers.net. (
nstld.verisign-grs.com. 2018091100 14400 7200 1209600 3600000 )
root-servers.net. 3600000 IN ZONEMD 2018091100 1 0 (
aadf7a017bccd8cefe6040494800249fd5edc3d49e2e8ce8db7522f47f
97f168db794bf5f679fbe0c8433fb66f7a0c26 )
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Internet-Draft DNS Zone Digest February 2019
Authors' Addresses
Duane Wessels
Verisign
12061 Bluemont Way
Reston, VA 20190
Phone: +1 703 948-3200
Email: dwessels@verisign.com
URI: http://verisign.com
Piet Barber
Verisign
12061 Bluemont Way
Reston, VA 20190
Phone: +1 703 948-3200
Email: pbarber@verisign.com
URI: http://verisign.com
Matt Weinberg
Verisign
12061 Bluemont Way
Reston, VA 20190
Phone: +1 703 948-3200
Email: mweinberg@verisign.com
URI: http://verisign.com
Warren Kumari
Google
1600 Amphitheatre Parkway
Mountain View, CA 94043
Email: warren@kumari.net
Wes Hardaker
USC/ISI
P.O. Box 382
Davis, CA 95617
Email: ietf@hardakers.net
Wessels, et al. Expires August 17, 2019 [Page 27]
