Internet DRAFT - draft-ietf-dnsop-negative-trust-anchors
draft-ietf-dnsop-negative-trust-anchors
Domain Name System Operations P. Ebersman
Internet-Draft Comcast
Intended status: Informational W. Kumari
Expires: February 25, 2016 Google
C. Griffiths
Nominet
J. Livingood
Comcast
R. Weber
Nominum
August 24, 2015
Definition and Use of DNSSEC Negative Trust Anchors
draft-ietf-dnsop-negative-trust-anchors-13
Abstract
DNS Security Extensions (DNSSEC) is now entering widespread
deployment. However, domain signing tools and processes are not yet
as mature and reliable as those for non-DNSSEC-related domain
administration tools and processes. This document defines Negative
Trust Anchors which can be used to mitigate DNSSEC validation
failures by disabling DNSSEC validation at specified domains.
[RFC Editor: Please remove this before publication. This document is
being stored in github at https://github.com/wkumari/draft-livingood-
dnsop-negative-trust-anchors . Authors accept pull requests, and keep
the latest (edit buffer) versions there, so commenters can follow
along at home.]
Status of This Memo
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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
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This Internet-Draft will expire on February 25, 2016.
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Copyright Notice
Copyright (c) 2015 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
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Table of Contents
1. Introduction and motivation . . . . . . . . . . . . . . . . . 3
1.1. Definition of a Negative Trust Anchor . . . . . . . . . . 3
1.2. Motivations for Negative Trust Anchors . . . . . . . . . 4
1.2.1. Mitigating Domain Validation Failures . . . . . . . . 4
1.2.2. Improving End User Experience . . . . . . . . . . . . 4
1.2.3. Avoiding Switching to a Non-Validating Resolver . . . 5
2. Use of a Negative Trust Anchor . . . . . . . . . . . . . . . 5
2.1. Applicability of Negative Trust Anchors . . . . . . . . . 6
3. Managing Negative Trust Anchors . . . . . . . . . . . . . . . 7
3.1. Alerting Users to Negative Trust Anchor Use . . . . . . . 7
4. Removal of a Negative Trust Anchor . . . . . . . . . . . . . 7
5. Comparison to Other DNS Misconfigurations . . . . . . . . . . 8
6. Intentionally Broken Domains . . . . . . . . . . . . . . . . 8
7. Discovering broken domains . . . . . . . . . . . . . . . . . 9
8. Privacy Considerations . . . . . . . . . . . . . . . . . . . 11
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11
10. Security Considerations . . . . . . . . . . . . . . . . . . . 11
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 12
12.1. Normative References . . . . . . . . . . . . . . . . . . 12
12.2. Informative References . . . . . . . . . . . . . . . . . 12
Appendix A. Configuration Examples . . . . . . . . . . . . . . . 13
A.1. NLNet Labs Unbound . . . . . . . . . . . . . . . . . . . 13
A.2. ISC BIND . . . . . . . . . . . . . . . . . . . . . . . . 14
A.3. Nominum Vantio . . . . . . . . . . . . . . . . . . . . . 14
Appendix B. Document Change Log . . . . . . . . . . . . . . . . 14
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
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1. Introduction and motivation
DNSSEC has now entered widespread deployment. However, the DNSSEC
signing tools and processes are less mature and reliable than those
for non-DNSSEC-related administration. As a result, operators of DNS
recursive resolvers, such as Internet Service Providers (ISPs),
occasionally observe domains incorrectly managing DNSSEC-related
resource records. This mismanagement triggers DNSSEC validation
failures, and then causes large numbers of end users to be unable to
reach a domain. Many end users tend to interpret this as a failure
of their ISP or resolver operator, and may switch to a non-validating
resolver or contact their ISP to complain, rather than seeing this as
a failure on the part of the domain they wanted to reach. Without
the techniques in this document, this pressure may cause the resolver
operator to disable (or simply not deploy) DNSSEC validation.
This document defines the Negative Trust Anchor (NTA), which can be
used during the transition to ubiquitous DNSSEC deployment. NTAs are
configured locally on a validating DNS recursive resolver to shield
end users from DNSSEC-related authoritative name server operational
errors. NTAs are intended to be temporary, and only implemented by
the organization requiring an NTA (and not distributed by any
organizations outside of the administrative boundary). Finally, NTAs
pertain only to DNSSEC and not to Public Key Infrastructures (PKI)
such as X.509.
Use of an NTA to temporarily disable DNSSEC validation for a specific
misconfigured domain name immediately restores access for end users.
This allows the domain's administrators to fix their
misconfiguration, while also allowing the organization using the NTA
to keep DNSSEC validation enabled and still reach the misconfigured
domain.
[ ED NOTE: Don't forget to insert 2119 boilerplate - not doing now,
to avoid messing up section numbers... ]
1.1. Definition of a Negative Trust Anchor
Trust Anchors are defined in [RFC5914]. A trust anchor is used by a
validating caching resolver as a starting point for building the
authentication chain for a signed DNS response. By way of analogy,
NTAs stop validation of the authentication chain. Instead, the
validator treats any upstream responses as if the zone is unsigned
and does not set the AD bit in responses it sends to clients. Note
that this is a behavior, and not a separate resource record. This
NTA can potentially be implemented at any level within the chain of
trust and would stop validation from that point in the chain down.
Validation starts again if there is a positive trust anchor further
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down in the chain. For example, if there is an NTA at example.com,
and a positive trust anchor at foo.bar.example.com, then validation
resumes for foo.bar.example.com and anything below it.
1.2. Motivations for Negative Trust Anchors
1.2.1. Mitigating Domain Validation Failures
A domain name can fail validation for two general reasons: a
legitimate security failure such as due to an attack or compromise of
some sort, or as a result of misconfiguration on the part of a zone
administrator. As domains transition to DNSSEC, the most common
reason for a validation failure has been misconfiguration. Thus,
domain administrators should be sure to read [RFC6781] in full. They
should also pay special attention to Section 4.2, pertaining to key
rollovers, which appear to be the cause of many recent validation
failures.
It is also possible that some DNSSEC validation failures could arise
due to differences in how different software developers interpret
DNSSEC standards and/or how those developers choose to implement
support for DNSSEC. For example, it is conceivable that a domain may
be DNSSEC signed properly, and one vendor's DNS recursive resolvers
will validate the domain but other vendors' software may fail to
validate the domain.
1.2.2. Improving End User Experience
End users generally do not know of, understand, or care about the
resolution process that causes connections to happen. This is by
design: the point of the DNS is to insulate users from having to
remember IP addresses through a friendlier way of naming systems. It
follows from this that end users do not, and should not, be expected
to know about DNSSEC, validation, or anything of the sort. As a
result, end users may misinterpret the failure to reach a domain due
to DNSSEC-related misconfiguration . They may (incorrectly) assume
that their ISP is purposely blocking access to the domain or that it
is a performance failure on the part of their ISP (especially of the
ISP's DNS servers). They may contact their ISP to complain, which
will incur cost for their ISP. In addition, they may use online
tools and sites to complain of this problem, such as via a blog, web
forum, or social media site, which may lead to dissatisfaction on the
part of other end users or general criticism of an ISP or operator of
a DNS recursive resolver.
As end users publicize these failures, others may recommend they
switch from security-aware DNS resolvers to resolvers not performing
DNSSEC validation. This is a shame since the ISP or other DNS
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recursive resolver operator is actually doing exactly what they are
supposed to do in failing to resolve a domain name; this is the
expected result when a domain can no longer be validated and it
protects end users from a potential security threat. Use of an NTA
would allow the ISP to specifically remedy the failure to reach that
domain, without compromising security for other sites. This would
result in a satisfied end user, with minimal impact to the ISP, while
maintaining the security of DNSSEC for correctly maintained domains.
It is worth noting the following text from [RFC4033] - "In the final
analysis, however, authenticating both DNS keys and data is a matter
of local policy, which may extend or even override the protocol
extensions defined in this document set." A responsibility (one of
many) of a caching server operator is to "protect the integrity of
the cache."
1.2.3. Avoiding Switching to a Non-Validating Resolver
As noted in Section 1.2.2, some people may consider switching to an
alternative, non-validating resolver themselves, or may recommend
that others do so. But if a domain fails DNSSEC validation and is
inaccessible, this could very well be due to a security-related
issue. In order to be as safe and secure as possible, end users
should not change to DNS servers that do not perform DNSSEC
validation as a workaround, and people should not recommend that
others do so either. Domains that fail DNSSEC for legitimate reasons
(versus misconfiguration) may be in control of hackers or there could
be other significant security issues with the domain.
Thus, switching to a non-validating resolver to restore access to a
domain that fails DNSSEC validation is not a recommended practice, is
bad advice to others, is potentially harmful to end user security.
2. Use of a Negative Trust Anchor
Technical personnel trained in the operation of DNS servers must
confirm that a DNSSEC validation failure is due to misconfiguration,
as a similar breakage could have occurred if an attacker gained
access to a domain's authoritative servers and modified those records
or had the domain pointed to their own rogue authoritative servers.
They should also confirm that the domain is not intentionally broken,
such as for testing purposes as noted in Section 6. Finally, they
should make a reasonable attempt to contact the domain owner of the
misconfigured zone, preferably prior to implementing the NTA.
Involving trained technical personnel is costly, but operational
experience suggests that this is a very rare event, usually on the
order of once per quarter (or even less).
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It is important for the resolver operator to confirm that the domain
is still under the ownership / control of the legitimate owner of the
domain in order to ensure that disabling validation for a specific
domain does not direct users to an address under an attacker's
control. Contacting the domain owner and telling them the DNSSEC
records that the resolver operator is seeing allows the resolver
operator to determine if the issue is a DNSSEC misconfiguration or an
attack.
In the case of a validation failure due to misconfiguration of a TLD
or popular domain name (such as a top 100 website), content or
services in the affected TLD or domain could be inaccessible for a
large number of users. In such cases, it may be appropriate to use
an NTA as soon as the misconfiguration is confirmed. An example of a
list of "top N" websites is the "Alexa Top 500 Sites on the Web"
[Alexa], , or a list of the of the most-accessed names in the
resolver's cache.
Once a domain has been confirmed to fail DNSSEC validation due to a
DNSSEC-related misconfiguration, an ISP or other DNS recursive
resolver operator may elect to use an NTA for that domain or sub-
domain. This instructs their DNS recursive resolver to temporarily
NOT perform DNSSEC validation at or in the misconfigured domain.
This immediately restores access to the domain for end users while
the domain's administrator corrects the misconfiguration(s). It does
not and should not involve turning off validation more broadly.
2.1. Applicability of Negative Trust Anchors
A NTA MUST only be used for a limited duration. Implementors SHOULD
allow the operator using the NTA to set an end time and date
associated with any NTA. Optimally, this time and date is set in a
DNS recursive resolver's configuration, though in the short-term this
may also be achieved via other systems or supporting processes. Use
of an NTA MUST NOT be automatic.
Finally, an NTA SHOULD be used only in a specific domain or sub-
domain and MUST NOT affect validation of other names up the
authentication chain. For example, an NTA for zone1.example.com
would affect only names at or below zone1.example.com, and validation
would still be performed on example.com, .com, and the root (".").
This NTA also SHOULD NOT affect names in another branch of the tree
(such as example.net). In another example, an NTA for example.com
would affect only names within example.com, and validation would
still be performed on .com, and the root ("."). In this scenario, if
there is a (probably manually configured) trust anchor for
zone1.example.com, validation would be performed for
zone1.example.com and subdomains of zone1.example.com.
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3. Managing Negative Trust Anchors
While NTAs have proven useful during the early stages of DNSSEC
adoption, domain owners are ultimately responsible for managing and
ensuring their DNS records are configured correctly.
Most current implementations of DNS validating resolvers currently
follow [RFC4033] on configuring a Trust Anchor using either a public
key as in a DNSKEY RR or a hash of a public key as in a DS RR.
Different DNS validators may have different configuration names for
an NTA. For examples see Appendix A.
An NTA placed at a node where there is a configured positive trust
anchor MUST take precedence over that trust anchor, effectively
disabling it. Implementations MAY issue a warning or informational
message when this occurs, so that operators are not surprised when
this happens.
3.1. Alerting Users to Negative Trust Anchor Use
End users of a DNS recursive resolver or other people may wonder why
a domain that fails DNSSEC validation resolves with a supposedly
validating resolver. As a result, implementors should consider
transparently disclosing those NTAs which are currently in place or
were in place in the past, such as on a website [Disclosure-Example].
This is particularly important since there is currently no special
DNS query response code that could indicate to end users or
applications that an NTA is in place. Such disclosures should
optimally include both the data and time that the NTA was put in
place and when it was removed.
4. Removal of a Negative Trust Anchor
As explored in Section 10, using an NTA once the zone correctly
validates can have security considerations. It is therefore
RECOMMENDED that NTA implementors should periodically attempt to
validate the domain in question, for the period of time that the NTA
is in place, until such validation is again successful. NTAs MUST
expire automatically when their configured lifetime ends. The
lifetime SHOULD NOT exceed a week. There is limited experience with
what this value should be, but at least one large vendor has
documented customer feedback suggesting that a week is reasonable
based on expectations of how long failures take to fix or to be
forgotten. Operational experience may further refine these
expectations.
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Before removing the NTA, all authoritative resolvers listed in the
zone should be checked (due to anycast and load balancers it may not
be possible to check all instances).
Once all testing succeeds, an NTA should be removed as soon as is
reasonably possible. One possible method to automatically determine
when the NTA can be removed is to send a periodic query for type SOA
at the NTA node; if it gets a response that it can validate (whether
the response was an actual SOA answer or a NOERROR/NODATA with
appropriate NSEC/NSEC3 records), the NTA is presumed no longer to be
necessary and is removed. Implementations SHOULD, by default,
perform this operation. Note that under some circumstances this is
undesirable behavior (for example, if www.example.com has a bad
signature, but example.com/SOA is fine) and so implementations may
wish to allow the operator to override this spot-check / behavior.
When removing the NTA, the implementation SHOULD remove all cached
entries at and below the NTA node.
5. Comparison to Other DNS Misconfigurations
Domain administrators are ultimately responsible for managing and
ensuring their DNS records are configured correctly. ISPs or other
DNS recursive resolver operators cannot and should not correct
misconfigured A, CNAME, MX, or other resource records of domains for
which they are not authoritative. Expecting non-authoritative
entities to protect domain administrators from any misconfiguration
of resource records is therefore unrealistic and unreasonable, and in
the long-term is harmful to the delegated design of the DNS and could
lead to extensive operational instability and/or variation.
With DNSSEC breakage, it is often possible to tell that there is a
misconfiguration by looking at the data and not needing to guess what
it should have been.
6. Intentionally Broken Domains
Some domains, such as dnssec-failed.org, have been intentionally
broken for testing purposes
[Measuring-DNSSEC-Validation-of-Website-Visitors] [Netalyzr]. For
example, dnssec-failed.org is a DNSSEC-signed domain that is broken.
If an end user is querying a validating DNS recursive resolver, then
this or other similarly intentionally broken domains should fail to
resolve and should result in a "Server Failure" error (RCODE 2, also
known as 'SERVFAIL'). If such a domain resolved successfully, then
it is a sign that the DNS recursive resolver is not fully validating.
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Organizations that utilize NTAs should not add an NTA for any
intentionally broken domain. Such additions are prevented by the
requirement that the operator attempt to contact the administrators
for the zone that has broken DNSSEC.
Organizations operating an intentionally broken domain may wish to
consider adding a TXT record for the domain to the effect of "This
domain is purposely DNSSEC broken for testing purposes".
7. Discovering broken domains
Discovering that a domain is DNSSEC broken as result of an operator
error instead of an attack is not trivial, and the examples here
should be vetted by an experienced professional before taking the
decision on implementing an NTA.
One of the key thing to look for when looking at a DNSSEC broken
domain is consistency and history. It therefore is good if you have
the ability to look at the server's DNS traffic over a long period of
time or have a database that stores DNS names associated answers
(this is often referred to as a "passive DNS database"). Another
invaluable tool is dnsviz (http://www.dnsivz.net) which also stores
DNSSEC related data historically. The drawback here is that you need
for it to have tested the domain before the incident occurs.
The first and easiest thing to check is if the failure of the domain
is consistent across different software implementations. If not, you
want to inform the vendor where it fails so that the vendor can look
more deeply into the issue.
The next thing is to figure out what the actual failure mode is. At
the time of this writing are several tools to do this, including:
o DNSViz (http://dnsviz.net)
o Verisign DNSSEC debugger (http://dnssec-debugger.verisignlabs.com)
o zonemaster (http://www.zonemaster.fr, https://github.com/dotse/
zonemaster)
most of these tools are open source and can be installed locally.
However, using the tools over the Internet has the advantage of
providing visibility from a different point. This is an incomplete
list, and it is expected that additional tools will be developed over
time to aid in troubleshooting DNSSEC issues.
Once you figure out what the error is, you need to check if it shows
consistently around the world and from all authoritative servers.
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Use DNS Tools (dig) or DNS looking glasses to verify this. An error
that is consistently the same is more likely to be operator caused
than an attack. Also if the output from the authoritative server is
consistently different from the resolvers' output this hints to an
attack rather then an error, unless there is EDNS0 client subnet
(draft-ietf-dnsop-edns-client-subnet) applied to the domain.
A last check is to look at the actual DNS data. Is the result of the
query still the same or has it changed? While a lot of DNSSEC errors
occur on events that change DNSSEC data, the actual record someone
wants to go to often stays the same. If the data is the same, this
is an indication (not a guarantee) that the error is operator caused.
Keep in mind that with DNS being used to globally balance traffic the
data associated to a name might be different in different parts of
the Internet.
Here are some examples of common DNSSEC failures that have been seen
as operator signing errors on the Internet:
o RRSIG timing issue. Each signature has an inception time and
expiry time, between which it is valid. Letting this time expire
without creating a new signature is one of the most common DNSSEC
errors. To a lesser extent, this also occurs if signatures were
made active before the inception time. For all of these errors
your primary check is to check on the data. Signature expiration
is also about the only error we see on actual data (like
www.example.com). All other errors are more or less related to
dealing with the chain of trust established by DS records in the
parent zone and DNSKEYs in the child zones. These mostly occur
during key rollovers, but are not limited to that.
o DNSKEYs in child zone don't match the DS record in the parent
zone. There is a big variation of this that can happen at any
point in the key lifecycle. DNSViz is the best tool to show
problems in the chain. If you debug yourself, use dig +multiline
so that you can see the key id of a DNSKEY. Common Variations of
this can be:
* DS pointing to a non existent key in the child zone. Questions
for consideration here include: Has there ever been a key (and,
if so, was it used)? Has there been a recent change in the
DNSKEY RRSet (indicating a key rollover)? Has the actual data
in the zone changed? Is the zone DNSSEC signed at all and has
it been in the past?
* DS pointing to an existent key, but no signatures are made with
the key. The checks above should be done, with the addition of
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checking if another key in the DNSKEY RRSet is now used to sign
the records.
* Data in DS or DNSKEY doesn't match the other. This is more
common in initial setup when there was a copy and paste error.
Again checking history on data is the best you can do there.
All of the above is just a starting point for consideration when
deciding whether or not to deploy a trust anchor. It is not possible
to provide a simple checklist to run through to determine whether a
domain is broken because of an attack or an operator error.
8. Privacy Considerations
There are no privacy considerations in this document.
9. IANA Considerations
There are no IANA considerations in this document.
10. Security Considerations
End to end DNSSEC validation will be disabled during the time that an
NTA is used. In addition, the NTA may be in place after the point in
time when the DNS misconfiguration that caused validation to break
has been fixed. Thus, there may be a gap between when a domain has
been re-secured and when an NTA is removed. In addition, an NTA may
be put in place by DNS recursive resolver operators without the
knowledge of the authoritative domain administrator for a given
domain name. However, attempts SHOULD be made to contact and inform
the domain administrator prior to putting the NTA in place.
One side effect of implementing an NTA is that it may break client
applications that assume that a domain is signed and expect an AD bit
in the response. It is expected that many application that require
DNSSEC for a domain will perform their own validation, and so this
should not be a major issue.
11. Acknowledgements
Several people made contributions of text to this document and/or
played an important role in the development and evolution of this
document. This in some cases included performing a detailed review
of this document and then providing feedback and constructive
criticism for future revisions, or engaging in a healthy debate over
the subject of the document. All of this was helpful and therefore
the following individuals merit acknowledgement: Joe Abley, John
Barnitz, Tom Creighton, Marco Davids, Brian Dickson, Patrik Falstrom,
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Tony Finch, Chris Ganster, Olafur Gudmundsson, Peter Hagopian,
Christer Holmberg, Wes Hardaker, Paul Hoffman, Shane Kerr, Murray
Kucherawy, Rick Lamb, Marc Lampo, Scott Rose, Ted Lemon, Wendy
Seltzer, A. Schulze, Antoin Verschuren, Paul Vixie, Patrik
Wallstrom, Nick Weaver, W.C.A. Wijngaards, Suzanne Woolf.
Edward Lewis, Evan Hunt, Andrew Sullivan and Tatuya Jinmei provided
especially large amounts of text and / or detailed review.
12. References
12.1. Normative References
[RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "DNS Security Introduction and Requirements", RFC
4033, DOI 10.17487/RFC4033, March 2005,
<http://www.rfc-editor.org/info/rfc4033>.
[RFC5914] Housley, R., Ashmore, S., and C. Wallace, "Trust Anchor
Format", RFC 5914, DOI 10.17487/RFC5914, June 2010,
<http://www.rfc-editor.org/info/rfc5914>.
[RFC6781] Kolkman, O., Mekking, W., and R. Gieben, "DNSSEC
Operational Practices, Version 2", RFC 6781, DOI 10.17487/
RFC6781, December 2012,
<http://www.rfc-editor.org/info/rfc6781>.
12.2. Informative References
[Alexa] Alexa, an Amazon.com Company, "Alexa "The top 500 sites on
the web. "", , May 2015, <http://www.alexa.com/topsites>.
[Disclosure-Example]
Comcast, "faa.gov Failing DNSSEC Validation (Fixed)",
Comcast , February 2013,
<http://dns.comcast.net/index.php/entry/
faa-gov-failing-dnssec-validation-fixed>.
[Measuring-DNSSEC-Validation-of-Website-Visitors]
Mens, J., "Is my Web site being used via a DNSSEC-
validator?", July 2012, <http://jpmens.net/2012/07/30/
is-my-web-site-being-used-via-dnssec-validator/>.
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[Netalyzr]
Weaver, N., Kreibich, C., Nechaev, B., and V. Paxson,
"Implications of Netalyzr's DNS Measurements", Securing
and Trusting Internet Names, SATIN 2011 SATIN 2011, April
2011, <http://conferences.npl.co.uk/satin/presentations/
satin2011slides-Weaver.pdf>.
[Unbound-Configuration]
Wijngaards, W., "Unbound: How to Turn Off DNSSEC", June
2010, <http://unbound.net/documentation/
howto_turnoff_dnssec.html>.
Appendix A. Configuration Examples
The section contains example configurations to achieve Negative Trust
Anchor functionality for the zone foo.example.com.
Note: These are simply examples - nameserver operators are expected
to test and understand the implications of these operations. Note
also that some of available implementations may not implement all
recommended functionality in this document. In that case it is
advisable to request the developer or vendor of the implementation to
support the missing feature, rather than start using the incomplete
implementation.
A.1. NLNet Labs Unbound
Unbound lets us simply disable validation checking for a specific
zone by adding configuration statements to unbound.conf:
server:
domain-insecure: "foo.example.com"
Using the 'unbound-control' command one can add and remove Negative
Trust Anchors without restarting the nameserver.
Using the "unbound-control" command:
list_insecure list domain-insecure zones
insecure_add zone add domain-insecure zone
insecure_remove zone remove domain-insecure zone
Items added with the "unbound-control" command are added to the
running server and are lost when the server is restarted. Items from
unbound.conf stay after restart.
For additional information see [Unbound-Configuration]
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A.2. ISC BIND
Use the "rndc" command:
nta -dump
List all negative trust anchors.
nta [-lifetime duration] [-force] domain [view]
Set a negative trust anchor, disabling DNSSEC validation
for the given domain.
Using -lifetime specifies the duration of the NTA, up
to one week. The default is one hour.
Using -force prevents the NTA from expiring before its
full lifetime, even if the domain can validate sooner.
nta -remove domain [view]
Remove a negative trust anchor, re-enabling validation
for the given domain.
A.3. Nominum Vantio
**
*negative-trust-anchors*
_Format_: name
_Command Channel_: view.update name=world negative-trust-
anchors=(foo.example.com)
_Command Channel_: resolver.update name=res1 negative-trust-
anchors=(foo.example.com)
*Description*: Disables DNSSEC validation for a domain, even if the
domain is under an existing security root.
Appendix B. Document Change Log
[RFC Editor: This section is to be removed before publication]
-12 to -13:
o ... and add Chris' email address.
o Finally incorporate Wendy Seltzer's pull request with tenst fixup
nits.
-11 to -12:
o Simply updated Chris' affiliation.
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-10.5 to 11
Integrated Alissa Cooper's No Objection comments. Text from Suz
and Evan.
-10.4 to 10.5
Integrated some comments from Ben Campbell's No Objection IESG
review.
-10.3 to 10.4
s/personnel trained in the operation of DNS servers MUST confirm/
personnel trained in the operation of DNS servers must confirm/ -
Alissa Cooper,
-10.2 to 10.3
o Integrated comments from Gen-ART review - Christer Holmberg.
o Offlist comment from Tony Finch. Made the "Negative Trust Anchors
are intended to be temporary," sentence much better.
-10.1 to 10.2
o Incoroprated comments from IETF LC, including:
o A. Schulze - s/Unound/Unbound/
o Joe Abley: Tone in into jarring. S1.2 s/domain administrator/zone
administrator/, dnscheck -> zonemaster
-10 to 10.1
o Fixed some typos (e.g Anrew -> Andrew)
-09 to -10
o 'Implementations MAY issue a warning or informational message when
this occurs' - changed SHOULD to MAY, per Evan.
-08 to -09
o Clarified that an NTA MUST take precedence over a positive, local
TA.
-07 to -08
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o Added some cleanup from Paul Hoffman and Evan Hunt.
o Some better text on how to make Unbound do this, provided by
W.C.A. Wijngaards.
-06 to -07
o Addressed a large number of comments from Paul Hoffman, Scott Rose
and some more from Jinmei.
-05 to -06
o A bunch of comments from Tony Finch.
-04 to -05
o A large bunch of cleanups from Jinmei. Thanks!
o Also clarified that if there is an NTA at foo.bar.baz.example, and
a positive *trust anchor* at bar.baz.example, the most specific
wins. I'm not very happy with this text, any additional text
gratefully accepted...
-03 to -04:
o Addressed some comment from an email from Jinmei that I had
missed. Turns out others had made many of the same comments, and
so most had already been addressed.
-02 to -03:
o Included text from Ralph into Appendix B
o A bunch of comments from Andrew Sullivan ('[DNSOP] negative-trust-
anchors-02" - Mar 18th)
o Updated keywords
-01 to -02:
o Gah! I forgot to run spell check. And I type like a chimpanzee
with bad hand-eye coordination...
-00 to -01:
o Stole chunks of text from Ed Lewis' mailing list "tirade" :-)
o New rndc usage text from Evan.
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o Deleted the (already resolved) open issues from Appendix C, moved
the unresolved issues into github, resolved them!
o Clarification that automated removal is best removal method, and
how to implement (Evan Hunt)
o Clarify that an NTA is not a RR (Rick Lamb)
o Grammar fixes.
Ind-07 - WG-00:
o Simply updated name to reflect WG doc.
Individual-00: First version published as an individual draft.
Individual-01: Fixed minor typos and grammatical nits. Closed all
open editorial items.
Individual-02: Simple date change to keep doc from expiring.
Substantive updates planned.
Individual-03: Changes to address feedback from Paul Vixie, by adding
a new section "Limited Time and Scope of Use". Changes to address
issues raised by Antoin Verschuren and Patrik Wallstrom, by adding a
new section "Intentionally Broken Domains" and added two related
references. Added text to address the need for manual investigation,
as suggested by Patrik Falstrom. Added a suggestion on notification
as suggested by Marc Lampo. Made several additions and changes
suggested by Ralf Weber, Wes Hardaker, Nick Weaver, Tony Finch, Shane
Kerr, Joe Abley, Murray Kucherawy, Olafur Gudmundsson.
Individual-04: Moved the section defining an NTA forward, and added
new text to the Abstract and Introduction per feedback from Paul
Hoffman.
Individual-05: Incorporated feedback from the DNSOP WG list received
on 2/17/13 and 2/18/13. This is likely the final version before the
IETF 86 draft cutoff date. Updated references to RFC6781 to RFC6781,
per March Davids.
Individual-06: Added more OPEN issues to continue tracking WG
discussion. No changes in the main document - just expanded issue
tracking.
Individual-07: Refresh document - needs revision and rework before
IETF-91. Planning to add more contributors.
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o Using github issue tracker - go see https://github.com/wkumari/
draft-livingood-dnsop-negative-trust-anchors for more details.
o A bunch of readability improvments.
o Issue: Notify the domain owner of the validation failure -
resolved.
o Issue: Make the NTA as specific as possible - resolved.
Authors' Addresses
Paul Ebersman
Comcast
One Comcast Center
1701 John F. Kennedy Boulevard
Philadelphia, PA 19103
US
Email: ebersman-ietf@dragon.net
Warren Kumari
Google
1600 Amphitheatre Parkway
Mountain View, CA 94043
US
Email: warren@kumari.net
URI: http://www.google.com
Chris Griffiths
Nominet
Minerva House
Edmund Halley Road
Oxford Science Park
Oxford OX4 4DQ
United Kingdom
Email: cgriffiths@gmail.com
URI: http://www.nominet.org.uk/
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Jason Livingood
Comcast
One Comcast Center
1701 John F. Kennedy Boulevard
Philadelphia, PA 19103
US
Email: jason_livingood@cable.comcast.com
URI: http://www.comcast.com
Ralf Weber
Nominum
Email: Ralf.Weber@nominum.com
URI: http://www.nominum.com
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