draft-ietf-dnsop-maintain-ds-03.txt   draft-ietf-dnsop-maintain-ds-04.txt 
dnsop O. Gudmundsson dnsop O. Gudmundsson
Internet-Draft CloudFlare Internet-Draft CloudFlare
Intended status: Standards Track P. Wouters Intended status: Standards Track P. Wouters
Expires: December 12, 2016 Red Hat Expires: May 4, 2017 Red Hat
June 10, 2016 October 31, 2016
Managing DS records from parent via CDS/CDNSKEY Managing DS records from parent via CDS/CDNSKEY
draft-ietf-dnsop-maintain-ds-03 draft-ietf-dnsop-maintain-ds-04
Abstract Abstract
RFC7344 specifies how DNS trust can be partially maintained in-band RFC7344 specifies how DNS trust can be maintained across key
between parent and child. There are two features missing in that rollovers in-band between parent and child. This document elevates
specification: initial trust setup and removal of trust anchor. This RFC7344 from informational to standards track and adds a standard
document addresses both these omissions. track method for initial trust setup and removal of secure entry
point.
Changing a domain's DNSSEC status can be a complicated matter Changing a domain's DNSSEC status can be a complicated matter
involving multiple unrelated parties. Some of these parties, such as involving multiple unrelated parties. Some of these parties, such as
the DNS operator, might not even be known by all the organizations the DNS operator, might not even be known by all the organizations
involved. The inability to disable DNSSEC via in-band signalling is involved. The inability to disable DNSSEC via in-band signaling is
seen as a problem or liability that prevents some DNSSEC adoption at seen as a problem or liability that prevents some DNSSEC adoption at
large scale. This document adds a method for in-band signalling of large scale. This document adds a method for in-band signaling of
these DNSSEC status changes. these DNSSEC status changes.
Initial trust is considered in general to be a hard technical This document describes reasonable policies to ease deployment of the
problem, this document sets forth reasonable policies that clarify initial acceptance of new secure entry points (DS records)
and simplify the initial acceptance policy.
It is preferable that operators collaborate on the transfer or move
of a domain. The best method is to perform a Key Signing Key ("KSK")
plus Zone Signing Key ("ZSK") rollover. If that is not possible, the
method using an unsigned intermediate state described in this
document can be used to move the domain between two parties. This
leaves the domain temporarily unsigned and vulnerable to DNS
spoofing, but that is preferred over the alternative of validation
failures due to a mismatched DS and DNSKEY record.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on December 12, 2016. This Internet-Draft will expire on May 4, 2017.
Copyright Notice Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Introducing a DS record . . . . . . . . . . . . . . . . . 3 1.1. Introducing a DS record . . . . . . . . . . . . . . . . . 3
1.2. Removing a DS Record . . . . . . . . . . . . . . . . . . 3 1.2. Removing a DS Record . . . . . . . . . . . . . . . . . . 3
1.3. Notation . . . . . . . . . . . . . . . . . . . . . . . . 4 1.3. Notation . . . . . . . . . . . . . . . . . . . . . . . . 4
1.4. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4 1.4. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. The Three Uses of CDS . . . . . . . . . . . . . . . . . . . . 4 2. The Three Uses of CDS . . . . . . . . . . . . . . . . . . . . 4
2.1. The meaning of the CDS RRset . . . . . . . . . . . . . . 5 2.1. The meaning of the CDS RRset . . . . . . . . . . . . . . 5
3. Enabling DNSSEC via CDS/CDNSKEY . . . . . . . . . . . . . . . 5 3. Enabling DNSSEC via CDS/CDNSKEY . . . . . . . . . . . . . . . 5
3.1. Accept policy via authenticated channel . . . . . . . . . 5 3.1. Accept policy via authenticated channel . . . . . . . . . 6
3.2. Accept with extra checks . . . . . . . . . . . . . . . . 5 3.2. Accept with extra checks . . . . . . . . . . . . . . . . 6
3.3. Accept after delay . . . . . . . . . . . . . . . . . . . 6 3.3. Accept after delay . . . . . . . . . . . . . . . . . . . 6
3.4. Accept with challenge . . . . . . . . . . . . . . . . . . 6 3.4. Accept with challenge . . . . . . . . . . . . . . . . . . 6
4. DNSSEC Delete Algorithm . . . . . . . . . . . . . . . . . . . 6 3.5. Accept from inception . . . . . . . . . . . . . . . . . . 7
5. Security considerations . . . . . . . . . . . . . . . . . . . 7 4. DNSSEC Delete Algorithm . . . . . . . . . . . . . . . . . . . 7
6. IANA considerations . . . . . . . . . . . . . . . . . . . . . 7 5. Security considerations . . . . . . . . . . . . . . . . . . . 8
6.1. Promoting RFC7344 to standards track . . . . . . . . . . 8 6. IANA considerations . . . . . . . . . . . . . . . . . . . . . 8
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 6.1. Promoting RFC7344 to standards track . . . . . . . . . . 9
7.1. Normative References . . . . . . . . . . . . . . . . . . 8 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
7.2. Informative References . . . . . . . . . . . . . . . . . 8 7.1. Normative References . . . . . . . . . . . . . . . . . . 9
Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 8 7.2. Informative References . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9
1. Introduction 1. Introduction
CDS/CDNSKEY [RFC7344] records are used to signal changes in trust CDS/CDNSKEY [RFC7344] records are used to signal changes in secure
anchors. This is one method to maintain delegations that can be used entry points. This is one method to maintain delegations that can be
when the DNS operator has no other way to inform the parent that used when the DNS operator has no other way to inform the parent that
changes are needed. changes are needed. This document elevates [RFC7344] from
informational to standards track RFC.
[RFC7344] is lacking two different options for full automated In addition, [RFC7344] is lacking two different options for full
operation to be possible. Firstly it did not define a method for the automated operation to be possible. It did not define a method for
Initial Trust establishment and left it to each parent to come up the Initial Trust establishment, leaving it open to each parent to
with an acceptance policy. Secondly it did not provide a "delete" come up with an acceptance policy. Additionally, [RFC7344] did not
signal for the child to tell the parent that it wants to remove the provide a "delete" signal for the child to inform the parent that the
DNSSEC security for its domain. DNSSEC security for its domain must be removed.
1.1. Introducing a DS record 1.1. Introducing a DS record
The big issue is how a child domain instructs the parent that it Automated insertion of DS records has been limited for many zones by
wants to have a DS record added. This problem can be solved using a the requirement that all changes pass through a "registry" of the
few simplifying assumptions. This document makes the assumption that child zone's parent. This has significantly hindered deployment of
there are reasonable policies that can be applied and will allow DNSSEC at large scale for DNS hosters, as the child zone owner is
automation of trust introduction. often not aware or able to update DNS records such as the DS record.
Not being able to enable trust via an easily automated mechanism is This document describes a few possible methods for the parent to
hindering DNSSEC at scale for DNS hosters that do not have automated accept a request by the child to add a DS record to its zone. These
access to the "registry" of the child zone's parent. methods have different security properties that addresses different
deployment scenarios, all resulting in an automated method of trust
introduction.
1.2. Removing a DS Record 1.2. Removing a DS Record
This document introduces the delete option for both CDS and CDNSKEY, This document introduces the delete option for both CDS and CDNSKEY,
allowing a child to signal to the parent to turn off DNSSEC. When a allowing a child to signal to the parent to turn off DNSSEC. When a
domain is moved from one DNS operator to another one, sometimes it is domain is moved from one DNS operator to another, sometimes it is
necessary to turn off DNSSEC to facilitate the change of DNS necessary to turn off DNSSEC to facilitate the change of DNS
operator. Common scenarios include: operator. Common scenarios include:
1 alternative to doing a proper DNSSEC algorithm rollover due to 1 Alternative to doing a proper DNSSEC algorithm rollover due to
operational limitations such as software limitations. operational limitations such as software limitations.
2 moving from a DNSSEC operator to a non-DNSSEC capable operator. 2 Moving from a DNSSEC operator to a non-DNSSEC capable operator.
3 moving to an operator that cannot/does-not-want to do a proper 3 Moving to an operator that cannot/does-not-want to do a proper
DNSSEC rollover. DNSSEC rollover.
4 when moving between two DNS operators that use disjoint sets of 4 When moving between two DNS operators that use disjoint sets of
algorithms to sign the zone, thus an algorithm rollover can not be algorithms to sign the zone, thus an algorithm rollover can not be
performed. performed.
5 the domain holder no longer wants DNSSEC enabled. 5 The domain holder no longer wants DNSSEC enabled.
The lack of a "remove my DNSSEC" option is cited as a reason why some The lack of a "remove my DNSSEC" option is cited as a reason why some
operators cannot deploy DNSSEC, as this is seen as an operational operators cannot deploy DNSSEC, as this is seen as an operational
risk. risk.
Turning off DNSSEC reduces the security of the domain and thus should Turning off DNSSEC reduces the security of the domain and thus should
only be done carefully, and that decision SHOULD be fully under the only be done carefully, and that decision should be fully under the
child domain's control. child domain's control.
1.3. Notation 1.3. Notation
When this document uses the word CDS it implies that the same applies Signaling can happen via CDS or CDNSKEY records. The only
to CDNSKEY and vice verse. The only differences between the two differences between the two records is how information is
records is how information is represented, and who calculates the DS represented, and who calculates the DS digest. For clarity, this
digiest. document uses the term "CDS" throughout the document to mean "either
CDS or CDNSKEY".
We use RRR to mean Registry Registrar Registrant in the context of
DNS domain markets.
When the document uses the word "parent" it implies an entity that is When the document uses the word "parent" it implies an entity that is
authorized to insert DS records into the parent zone on behalf of the authorized to insert DS records into the parent zone on behalf of the
child domain. Which entity this exactly is does not matter. It child domain. Which entity this exactly is does not matter. It
could be the Registrar or Reseller that the child domain was could be the Registrar or Reseller that the child domain was
purchased from. It could be the Registry that the domain is purchased from. It could be the Registry that the domain is
registered in when allowed. It could be some other entity when the registered in when allowed. Or it could be some other entity.
RRR framework is not used.
1.4. Terminology 1.4. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
2. The Three Uses of CDS 2. The Three Uses of CDS
In general there are three operations that a domain wants to In general there are three operations that a domain wants to instruct
influence on its parent: their parent to perform:
1 Enable DNSSEC validation, i.e. place an initial DS RRset in the 1 Enable DNSSEC validation, i.e. place an initial DS RRset in the
parent. parent.
2 Roll over KSK, this means updating the DS records in the parent to 2 Roll over the Key Signing Key ("KSK"), this means updating the DS
reflect the new set of KSK's at the child. This could be an ADD records in the parent to reflect the new set of KSK's at the
operation, a DELETE operation on one or more records while keeping child. This could be an ADD operation, a DELETE operation on one
at least one DS RR, or a full REPLACE operation. or more records while keeping at least one DS RR, or a full
REPLACE operation.
3 Turn off DNSSEC validation, i.e. delete all the DS records. 3 Turn off DNSSEC validation, i.e. delete all the DS records.
Operation 2 is covered in [RFC7344], operations 1 and 3 are defined Rolling the KSK is covered in [RFC7344]. It is considered the safest
in this document. In many people's minds, those two operations carry use case of a CDS/CDNSKEY record as it makes no change to the trust
more risk than the first one. This document argues that 3 is relationship between parent and child. Introduction and removal of
identical to 2 and the first one is different (but not that DS records are defined in this document. As these CDS/CDNSKEY use
different). cases create or end the trust relationship between the parent and
child, these use cases should be carefully implemented and monitored.
2.1. The meaning of the CDS RRset 2.1. The meaning of the CDS RRset
The semantic meaning of publishing a CDS RRset is interpreted to The semantic meaning of publishing a CDS RRset is interpreted to
mean: mean:
"Publishing a CDS or CDNSKEY record signals to the parent that the "Publishing a CDS or CDNSKEY record signals to the parent that the
child desires that the corresponding DS records be synchronized. child desires that the corresponding DS records be synchronized.
Every parent or parental agent should have an acceptance policy of Every parent or parental agent should have an acceptance policy of
these records for the three different use cases involved: Initial DS these records for the three different use cases involved: Initial DS
publication, Key rollover, and Returning to Insecure." publication, Key rollover, and Returning to Insecure."
In short, the CDS RRset is an instruction to the parent to modify the In short, the CDS RRset is an instruction to the parent to modify the
DS RRset if the CDS and DS Reset's differ. The acceptance policy for DS RRset if the CDS and DS Reset's differ.
CDS in the rollover case is "seeing" according to [RFC7344]. The
acceptance policy in the Delete case is seeing a (validly signed) CDS The acceptance policy for CDS in the rollover case is "seeing"
RRset with the delete operation specified in this document. according to [RFC7344]. The acceptance policy in the Delete case is
seeing a (validly signed) CDS RRset with the delete operation
specified in this document.
3. Enabling DNSSEC via CDS/CDNSKEY 3. Enabling DNSSEC via CDS/CDNSKEY
There are number of different models for managing initial trust, but There are number of different models for managing initial trust, but
in the general case, the child wants to enable global validation for in the general case, the child wants to enable global validation. As
the future. Thus during the period from the time the child publishes long as the child is insecure, DNS answers can be forged. The goal
the CDS until the corresponding DS is published at the parent is the is to promote the child from insecure to secure as soon as reasonably
period that DNS answers for the child could be forged. The goal is possible by the parent. This means that the period from the child's
to keep this period as short as possible. publication of CDS/CDNSKEY RRset to the parent publishing the
synchronized DS RRset should be as short as possible.
One important case is how a third party DNS operator can upload its One important use case is how a third party DNS operator can upload
DNSSEC information to the parent, so the parent can publish a DS its DNSSEC information to the parent, so the parent can publish a DS
record for the child. In this case there is a possibility of setting record for the child. In this case there is a possibility of setting
up some kind of authentication mechanism and submission mechanism up some kind of authentication mechanism and submission mechanism
that is outside the scope of this document. that is outside the scope of this document.
Below are some policies that parents can use. These policies assume Below are some policies that parents can use. These policies assume
that the notifications can be verified or authenticated. that the notifications can be verified or authenticated.
3.1. Accept policy via authenticated channel 3.1. Accept policy via authenticated channel
In this case the parent is notified via authenticated channel UI/API In this case the parent is notified via authenticated channel UI/API
that a CDS/CDNSKEY RRset exists. In the case of a CDS RRset the that a CDS/CDNSKEY RRset exists. In the case of a CDS RRset the
parent retrieves the CDS and inserts the corresponding DS RRset as parent retrieves the CDS RRset and inserts the corresponding DS RRset
requested. In the case of CDNSKEY the parent retrieves the CDNSKEY as requested. In the case of CDNSKEY the parent retrieves the
RRset and calculates the DS record(s). CDNSKEY RRset and calculates the DS record(s). Parents may limit the
DS record type based on local policy. Parents SHOULD NOT refuse CDS/
CDNSKEY updates that do not (yet) have a matching DNSKEY in the child
zone. This will allow the child to prepublish a spare (and
potentially offline) DNSKEY.
3.2. Accept with extra checks 3.2. Accept with extra checks
In this case the parent checks that the source of the notification is In this case the parent checks that the source of the notification is
allowed to request the DS insertion. The checks could include allowed to request the DS insertion. The checks could include
whether this is a trusted entity, whether the nameservers correspond whether this is a trusted entity, whether the nameservers correspond
to the requester, whether there have been any changes in registration to the requester, whether there have been any changes in registration
in the last few days, etc. The parent can also send a notification in the last few days, etc. The parent can also send a notification
requesting a confirmation, for example by sending email to the requesting a confirmation, for example by sending email to the
registrant requesting a confirmation. The end result is that the CDS registrant requesting a confirmation. The end result is that the CDS
RRset is accepted at the end of the checks or when the out-of-band RRset is accepted at the end of the checks or when the out-of-band
confirmation is received. confirmation is received. Any extra checks should have proper rate
limiting in place to prevent abuse.
3.3. Accept after delay 3.3. Accept after delay
In this case, if the parent deems the request valid, it starts In this case, if the parent deems the request valid, it starts
monitoring the CDS RRset at the child nameservers over period of time monitoring the CDS RRset at the child nameservers over period of time
to make sure nothing changes. After some time or after a number of to make sure nothing changes. After some time or after a number of
checks, preferably from different vantage points in the network, the checks, preferably from different vantage points in the network, the
parent accepts the CDS RRset as a valid signal to update its DS RRset parent accepts the CDS RRset as a valid signal to update its DS RRset
for this child. for this child.
3.4. Accept with challenge 3.4. Accept with challenge
In this case the parent instructs the requester to insert some record In this case the parent instructs the requester to insert some record
into the child domain to prove it has the ability to do so (i.e., it into the child domain to prove it has the ability to do so (i.e., it
is the operator of the zone). is the operator of the zone). This method imposes a new task on the
parent to monitor the child zone to see if the challenge has been
added to the zone. The parent should verify the challenge is
published by all the child's nameservers and should test for this
challenge from various diverse network locations to increase the
security of this method as much as possible.
3.5. Accept from inception
If a parent is adding a new child domain that is not currently
delegated at all, it could use the child CDS/CDNSKEY RRset to
immediately publish a DS RRset along with the new NS RRset. This
would ensure that the new child domain is never active in an insecure
state.
4. DNSSEC Delete Algorithm 4. DNSSEC Delete Algorithm
The DNSKEY algorithm registry contains two reserved values: 0 and This document defines the previously reserved DNS Security Algorithm
255[RFC4034]. The CERT record [RFC4398] defines the value 0 to mean Number of value 0 in the context of CDS and CDNSKEY records to mean
the algorithm in the CERT record is not defined in DNSSEC. that the entire DS RRset at the parent must be removed. The value 0
remains reserved for the DS and DNSKEY records.
For this reason, using the value 0 in CDS/CDNSKEY delete operations No DNSSEC validator can treat algorithm 0 as a valid signature
is potentially problematic, but we propose it here anyway as the risk algorithm. If a validator sees a DNSKEY or DS record with this
is minimal. The alternative is to reserve a DNSSEC algorithm number algorithm value, it must treat it as unknown. Accordingly, the zone
for this purpose. is treated as unsigned unless there are other algorithms present. In
general the value 0 should never be used in the context of DNSKEY and
DS records.
Right now, no DNSSEC validator understands algorithm 0 as a valid The CERT record [RFC4398] defines the value 0 similarly to mean the
signature algorithm. If a validator sees a DNSKEY or DS record with algorithm in the CERT record is not defined in DNSSEC.
this algorithm value, it MUST treat it as unknown. Accordingly, the
zone is treated as unsigned unless there are other algorithms
present. In general the value 0 should never be used in the context
of DNSKEY and DS records.
In the context of CDS and CDNSKEY records, DNSSEC algorithm 0 is The contents of the CDS or CDNSKEY RRset MUST contain one RR and only
defined to mean that the entire DS RRset MUST be removed. The
contents of the CDS or CDNSKEY RRset MUST contain one RR and only
contain the exactly the fields as shown below. contain the exactly the fields as shown below.
1 CDS 0 0 0 1 CDS 0 0 0
2 CDNSKEY 0 3 0 2 CDNSKEY 0 3 0
The keying material payload is represented by a single 0. This The keying material payload is represented by a single 0. This
record is signed in the same way as regular CDS/CDNSKEY RRset's are record is signed in the same way as regular CDS/CDNSKEY RRsets are
signed. This is a change in format from strict interpretation of signed. This is a change in format from strict interpretation of
[RFC7344] and may cause problems with some deployed software. [RFC7344] and may cause problems with some deployed software.
Strictly speaking the CDS record could be "CDS X 0 X" as only the Strictly speaking the CDS record could be "CDS X 0 X" as only the
DNSKEY algorithm is what signals the DELETE operation, but for DNSKEY algorithm is what signals the DELETE operation, but for
clarity the "0 0 0" notation is mandated - this is not a definition clarity the "0 0 0" notation is mandated - this is not a definition
of DS Digest algorithm 0. The same argument applies to "CDNSKEY 0 3 of DS Digest algorithm 0. The same argument applies to "CDNSKEY 0 3
0", the value 3 in second field is mandated by RFC4034 section 2.1.2. 0", the value 3 in second field is mandated by [RFC4034] section
2.1.2.
Once the parent has verified the CDS/CDNSKEY RRset and it has passed Once the parent has verified the CDS/CDNSKEY RRset and it has passed
other acceptance tests, the parent MUST remove the DS RRset. After other acceptance tests, the parent MUST remove the DS RRset. After
waiting a sufficient amount of time - depending on the parental TTL's waiting a sufficient amount of time - depending on the parental TTL's
- the child can start the process of turning off DNSSEC. - the child can start the process of turning off DNSSEC.
5. Security considerations 5. Security considerations
This document's main goal is to avoid validation failures when a Turning off DNSSEC reduces the security of the domain and thus should
domain moves from one DNS operator to another. Turning off DNSSEC only be done as a last resort in preventing DNSSEC validation errors
reduces the security of the domain and thus should only be done as a due to mismatched DS and DNSKEY records.
last resort.
In most cases it is preferable that operators collaborate on the
rollover by doing a KSK+ZSK rollover as part of the hand-off, but
that is not always possible. This document addresses the case where
unsigned state is needed to complete a rollover.
Users SHOULD keep in mind that re-establishing trust in delegation Users should keep in mind that re-establishing trust in delegation
can be hard and takes a long time. Before deciding to complete the can be hard and takes time. Before deciding to complete the rollover
rollover via an unsigned state, all options SHOULD be considered. via an unsigned state, all other options should be considered first.
A parent SHOULD ensure that when it is allowing a child to become A parent SHOULD ensure that when it is allowing a child to become
securely delegated, that it has a reasonable assurance that the CDS/ securely delegated, that it has a reasonable assurance that the CDS/
CDNSKEY RRset that is used to bootstrap the security is visible from CDNSKEY RRset that is used to bootstrap the security is visible from
a geographically and topologically diverse view. It SHOULD also a geographically and topologically diverse view. It SHOULD also
ensure that the zone validates correctly if the parent publishes the ensure that the zone validates correctly if the parent publishes the
DS record. A parent zone might also consider sending an email to its DS record. A parent zone might also consider sending an email to its
contact addresses to give the child zone a warning that security will contact addresses to give the child zone a warning that security will
be enabled after a certain amount of wait time - thus allowing a be enabled after a certain amount of wait time - thus allowing a
child administrator to cancel the request. child administrator to cancel the request.
This document describes a few possible acceptance criteria for the
Initial Trust establishment. Due to a large variety of legal
frameworks surrounding parent domains (TLDs in particular) this
document cannot give a definitive list of valid acceptance criteria.
Parental zones should look at the listed methods and pick the most
secure method possible within their legal and technical scenario,
possibly further securing the acceptance criteria, as long as the
deployed method still enables a fully automated method for non-direct
parties such as third party DNS hosters.
6. IANA considerations 6. IANA considerations
This document updates the following IANA registries: "DNS Security This document updates entry number 0 of the "DNS Security Algorithm
Algorithm Numbers" Numbers" IANA Registry as follows:
Algorithm 0 adds a reference to this document. +------+---------+-------+-------+-------+--------------------------+
| Numb | Descrip | Mnemo | Zone | Trans | Reference |
| er | tion | nic | Signi | . | |
| | | | ng | Sec. | |
+------+---------+-------+-------+-------+--------------------------+
| 0 | Delete | DELET | N | N | [RFC4034][RFC4398]RFC- |
| | DS | E | | | THIS-DOCUMENT] |
+------+---------+-------+-------+-------+--------------------------+
6.1. Promoting RFC7344 to standards track 6.1. Promoting RFC7344 to standards track
Experience has shown that CDS/CDNSKEY are useful in the deployment of Experience has shown that CDS/CDNSKEY are useful in the deployment of
DNSSEC. [RFC7344] was published as Informational, this document DNSSEC. [RFC7344] was published as Informational, this document
elevates RFC7344 to standards track. elevates RFC7344 to standards track.
7. References 7. References
7.1. Normative References 7.1. Normative References
[RFC4034] Arends, R., Austein, R., Larson, M., Massey, D., and S. [RFC4034] Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "Resource Records for the DNS Security Extensions", Rose, "Resource Records for the DNS Security Extensions",
RFC 4034, DOI 10.17487/RFC4034, March 2005, RFC 4034, DOI 10.17487/RFC4034, March 2005,
<http://www.rfc-editor.org/info/rfc4034>. <http://www.rfc-editor.org/info/rfc4034>.
[RFC7344] Kumari, W., Gudmundsson, O., and G. Barwood, "Automating [RFC7344] Kumari, W., Gudmundsson, O., and G. Barwood, "Automating
DNSSEC Delegation Trust Maintenance", RFC 7344, DOI DNSSEC Delegation Trust Maintenance", RFC 7344,
10.17487/RFC7344, September 2014, DOI 10.17487/RFC7344, September 2014,
<http://www.rfc-editor.org/info/rfc7344>. <http://www.rfc-editor.org/info/rfc7344>.
7.2. Informative References 7.2. Informative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/ Requirement Levels", BCP 14, RFC 2119,
RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>. <http://www.rfc-editor.org/info/rfc2119>.
[RFC4398] Josefsson, S., "Storing Certificates in the Domain Name [RFC4398] Josefsson, S., "Storing Certificates in the Domain Name
System (DNS)", RFC 4398, DOI 10.17487/RFC4398, March 2006, System (DNS)", RFC 4398, DOI 10.17487/RFC4398, March 2006,
<http://www.rfc-editor.org/info/rfc4398>. <http://www.rfc-editor.org/info/rfc4398>.
Appendix A. Acknowledgements Appendix A. Acknowledgments
This document is generated using the mmark tool that Miek Gieben has This document is generated using the mmark tool that Miek Gieben has
developed. We thank number of people that have provided feedback and developed. We thank number of people that have provided feedback and
useful comments including Bob Harold, John Levine, Matthijs Mekking, useful comments including Bob Harold, John Levine, Matthijs Mekking,
Dan York, Shane Kerr, Jacques Latour. Dan York, Shane Kerr, Jacques Latour.
Authors' Addresses Authors' Addresses
Olafur Gudmundsson Olafur Gudmundsson
CloudFlare CloudFlare
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