4 Network Working Group S. Weiler
5 Internet-Draft SPARTA, Inc.
6 Updates: 4033, 4034, 4035, 5155 D. Blacka
7 (if approved) VeriSign, Inc.
8 Intended status: Standards Track March 8, 2010
9 Expires: September 9, 2010
12 Clarifications and Implementation Notes for DNSSECbis
13 draft-ietf-dnsext-dnssec-bis-updates-10
17 This document is a collection of technical clarifications to the
18 DNSSECbis document set. It is meant to serve as a resource to
19 implementors as well as a repository of DNSSECbis errata.
23 This Internet-Draft is submitted to IETF in full conformance with the
24 provisions of BCP 78 and BCP 79.
26 Internet-Drafts are working documents of the Internet Engineering
27 Task Force (IETF), its areas, and its working groups. Note that
28 other groups may also distribute working documents as Internet-
31 Internet-Drafts are draft documents valid for a maximum of six months
32 and may be updated, replaced, or obsoleted by other documents at any
33 time. It is inappropriate to use Internet-Drafts as reference
34 material or to cite them other than as "work in progress."
36 The list of current Internet-Drafts can be accessed at
37 http://www.ietf.org/ietf/1id-abstracts.txt.
39 The list of Internet-Draft Shadow Directories can be accessed at
40 http://www.ietf.org/shadow.html.
42 This Internet-Draft will expire on September 9, 2010.
46 Copyright (c) 2010 IETF Trust and the persons identified as the
47 document authors. All rights reserved.
49 This document is subject to BCP 78 and the IETF Trust's Legal
50 Provisions Relating to IETF Documents
51 (http://trustee.ietf.org/license-info) in effect on the date of
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60 publication of this document. Please review these documents
61 carefully, as they describe your rights and restrictions with respect
62 to this document. Code Components extracted from this document must
63 include Simplified BSD License text as described in Section 4.e of
64 the Trust Legal Provisions and are provided without warranty as
65 described in the BSD License.
70 1. Introduction and Terminology . . . . . . . . . . . . . . . . . 3
71 1.1. Structure of this Document . . . . . . . . . . . . . . . . 3
72 1.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
73 2. Important Additions to DNSSSECbis . . . . . . . . . . . . . . 3
74 2.1. NSEC3 Support . . . . . . . . . . . . . . . . . . . . . . 3
75 2.2. SHA-256 Support . . . . . . . . . . . . . . . . . . . . . 4
76 3. Security Concerns . . . . . . . . . . . . . . . . . . . . . . 4
77 3.1. Clarifications on Non-Existence Proofs . . . . . . . . . . 4
78 3.2. Validating Responses to an ANY Query . . . . . . . . . . . 5
79 3.3. Check for CNAME . . . . . . . . . . . . . . . . . . . . . 5
80 3.4. Insecure Delegation Proofs . . . . . . . . . . . . . . . . 5
81 4. Interoperability Concerns . . . . . . . . . . . . . . . . . . 5
82 4.1. Errors in Canonical Form Type Code List . . . . . . . . . 5
83 4.2. Unknown DS Message Digest Algorithms . . . . . . . . . . . 6
84 4.3. Private Algorithms . . . . . . . . . . . . . . . . . . . . 6
85 4.4. Caution About Local Policy and Multiple RRSIGs . . . . . . 7
86 4.5. Key Tag Calculation . . . . . . . . . . . . . . . . . . . 7
87 4.6. Setting the DO Bit on Replies . . . . . . . . . . . . . . 7
88 4.7. Setting the AD Bit on Queries . . . . . . . . . . . . . . 8
89 4.8. Setting the AD Bit on Replies . . . . . . . . . . . . . . 8
90 4.9. Setting the CD bit on Requests . . . . . . . . . . . . . . 8
91 4.10. Nested Trust Anchors . . . . . . . . . . . . . . . . . . . 8
92 4.10.1. Closest Encloser . . . . . . . . . . . . . . . . . . 9
93 4.10.2. Accept Any Success . . . . . . . . . . . . . . . . . 9
94 4.10.3. Preference Based on Source . . . . . . . . . . . . . 10
95 5. Minor Corrections and Clarifications . . . . . . . . . . . . . 10
96 5.1. Finding Zone Cuts . . . . . . . . . . . . . . . . . . . . 10
97 5.2. Clarifications on DNSKEY Usage . . . . . . . . . . . . . . 10
98 5.3. Errors in Examples . . . . . . . . . . . . . . . . . . . . 11
99 5.4. Errors in RFC 5155 . . . . . . . . . . . . . . . . . . . . 11
100 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
101 7. Security Considerations . . . . . . . . . . . . . . . . . . . 12
102 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 12
103 8.1. Normative References . . . . . . . . . . . . . . . . . . . 12
104 8.2. Informative References . . . . . . . . . . . . . . . . . . 13
105 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . . 13
106 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14
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116 1. Introduction and Terminology
118 This document lists some additions, clarifications and corrections to
119 the core DNSSECbis specification, as originally described in
120 [RFC4033], [RFC4034], and [RFC4035], and later amended by [RFC5155].
121 (See section Section 2 for more recent additions to that core
124 It is intended to serve as a resource for implementors and as a
125 repository of items that need to be addressed when advancing the
126 DNSSECbis documents from Proposed Standard to Draft Standard.
128 1.1. Structure of this Document
130 The clarifications to DNSSECbis are sorted according to their
131 importance, starting with ones which could, if ignored, lead to
132 security problems and progressing down to clarifications that are
133 expected to have little operational impact.
137 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
138 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
139 document are to be interpreted as described in [RFC2119].
142 2. Important Additions to DNSSSECbis
144 This section lists some documents that should be considered core
145 DNSSEC protocol documents in addition to those originally specified
146 in Section 10 of [RFC4033].
150 [RFC5155] describes the use and behavior of the NSEC3 and NSEC3PARAM
151 records for hashed denial of existence. Validator implementations
152 are strongly encouraged to include support for NSEC3 because a number
153 of highly visible zones are expected to use it. Validators that do
154 not support validation of responses using NSEC3 will likely be
155 hampered in validating large portions of the DNS space.
157 [RFC5155] should be considered part of the DNS Security Document
158 Family as described by [RFC4033], Section 10.
160 Note that the algorithm identifiers defined in RFC5155 (DSA-NSEC3-
161 SHA1 and RSASHA1-NSEC3-SHA1) signal that a zone MAY be using NSEC3,
162 rather than NSEC. The zone MAY indeed be using either and validators
163 supporting these algorithms MUST support both NSEC3 and NSEC
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176 [RFC4509] describes the use of SHA-256 as a digest algorithm in
177 Delegation Signer (DS) RRs. [RFC5702] describes the use of the
178 RSASHA256 algorithm in DNSKEY and RRSIG RRs. Validator
179 implementations are strongly encouraged to include support for this
180 algorithm for DS, DNSKEY, and RRSIG records.
182 Both [RFC4509] and [RFC5702] should also be considered part of the
183 DNS Security Document Family as described by [RFC4033], Section 10.
188 This section provides clarifications that, if overlooked, could lead
191 3.1. Clarifications on Non-Existence Proofs
193 [RFC4035] Section 5.4 under-specifies the algorithm for checking non-
194 existence proofs. In particular, the algorithm as presented would
195 incorrectly allow an NSEC or NSEC3 RR from an ancestor zone to prove
196 the non-existence of RRs in the child zone.
198 An "ancestor delegation" NSEC RR (or NSEC3 RR) is one with:
201 o the SOA bit clear, and
202 o a signer field that is shorter than the owner name of the NSEC RR,
203 or the original owner name for the NSEC3 RR.
205 Ancestor delegation NSEC or NSEC3 RRs MUST NOT be used to assume non-
206 existence of any RRs below that zone cut, which include all RRs at
207 that (original) owner name other than DS RRs, and all RRs below that
208 owner name regardless of type.
210 Similarly, the algorithm would also allow an NSEC RR at the same
211 owner name as a DNAME RR, or an NSEC3 RR at the same original owner
212 name as a DNAME, to prove the non-existence of names beneath that
213 DNAME. An NSEC or NSEC3 RR with the DNAME bit set MUST NOT be used
214 to assume the non-existence of any subdomain of that NSEC/NSEC3 RR's
215 (original) owner name.
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228 3.2. Validating Responses to an ANY Query
230 [RFC4035] does not address how to validate responses when QTYPE=*.
231 As described in Section 6.2.2 of [RFC1034], a proper response to
232 QTYPE=* may include a subset of the RRsets at a given name. That is,
233 it is not necessary to include all RRsets at the QNAME in the
236 When validating a response to QTYPE=*, all received RRsets that match
237 QNAME and QCLASS MUST be validated. If any of those RRsets fail
238 validation, the answer is considered Bogus. If there are no RRsets
239 matching QNAME and QCLASS, that fact MUST be validated according to
240 the rules in [RFC4035] Section 5.4 (as clarified in this document).
241 To be clear, a validator must not expect to receive all records at
242 the QNAME in response to QTYPE=*.
246 Section 5 of [RFC4035] says little about validating responses based
247 on (or that should be based on) CNAMEs. When validating a NOERROR/
248 NODATA response, validators MUST check the CNAME bit in the matching
249 NSEC or NSEC3 RR's type bitmap in addition to the bit for the query
250 type. Without this check, an attacker could successfully transform a
251 positive CNAME response into a NOERROR/NODATA response.
253 3.4. Insecure Delegation Proofs
255 [RFC4035] Section 5.2 specifies that a validator, when proving a
256 delegation is not secure, needs to check for the absence of the DS
257 and SOA bits in the NSEC (or NSEC3) type bitmap. The validator also
258 needs to check for the presence of the NS bit in the matching NSEC
259 (or NSEC3) RR (proving that there is, indeed, a delegation), or
260 alternately make sure that the delegation is covered by an NSEC3 RR
261 with the Opt-Out flag set. If this is not checked, spoofed unsigned
262 delegations might be used to claim that an existing signed record is
266 4. Interoperability Concerns
268 4.1. Errors in Canonical Form Type Code List
270 When canonicalizing DNS names, DNS names in the RDATA section of NSEC
271 and RRSIG resource records are not downcased.
273 [RFC4034] Section 6.2 item 3 has a list of resource record types for
274 which DNS names in the RDATA are downcased for purposes of DNSSEC
275 canonical form (for both ordering and signing). That list
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284 erroneously contains NSEC and RRSIG. According to [RFC3755], DNS
285 names in the RDATA of NSEC and RRSIG should not be downcased.
287 The same section also erroneously lists HINFO, and twice at that.
288 Since HINFO records contain no domain names, they are not subject to
291 4.2. Unknown DS Message Digest Algorithms
293 Section 5.2 of [RFC4035] includes rules for how to handle delegations
294 to zones that are signed with entirely unsupported public key
295 algorithms, as indicated by the key algorithms shown in those zone's
296 DS RRsets. It does not explicitly address how to handle DS records
297 that use unsupported message digest algorithms. In brief, DS records
298 using unknown or unsupported message digest algorithms MUST be
299 treated the same way as DS records referring to DNSKEY RRs of unknown
300 or unsupported public key algorithms.
302 The existing text says:
304 If the validator does not support any of the algorithms listed in
305 an authenticated DS RRset, then the resolver has no supported
306 authentication path leading from the parent to the child. The
307 resolver should treat this case as it would the case of an
308 authenticated NSEC RRset proving that no DS RRset exists, as
311 To paraphrase the above, when determining the security status of a
312 zone, a validator disregards any DS records listing unknown or
313 unsupported algorithms. If none are left, the zone is treated as if
316 Modified to consider DS message digest algorithms, a validator also
317 disregards any DS records using unknown or unsupported message digest
320 4.3. Private Algorithms
322 As discussed above, section 5.2 of [RFC4035] requires that validators
323 make decisions about the security status of zones based on the public
324 key algorithms shown in the DS records for those zones. In the case
325 of private algorithms, as described in [RFC4034] Appendix A.1.1, the
326 eight-bit algorithm field in the DS RR is not conclusive about what
327 algorithm(s) is actually in use.
329 If no private algorithms appear in the DS set or if any supported
330 algorithm appears in the DS set, no special processing will be
331 needed. In the remaining cases, the security status of the zone
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340 depends on whether or not the resolver supports any of the private
341 algorithms in use (provided that these DS records use supported hash
342 functions, as discussed in Section 4.2). In these cases, the
343 resolver MUST retrieve the corresponding DNSKEY for each private
344 algorithm DS record and examine the public key field to determine the
345 algorithm in use. The security-aware resolver MUST ensure that the
346 hash of the DNSKEY RR's owner name and RDATA matches the digest in
347 the DS RR. If they do not match, and no other DS establishes that
348 the zone is secure, the referral should be considered Bogus data, as
349 discussed in [RFC4035].
351 This clarification facilitates the broader use of private algorithms,
352 as suggested by [RFC4955].
354 4.4. Caution About Local Policy and Multiple RRSIGs
356 When multiple RRSIGs cover a given RRset, [RFC4035] Section 5.3.3
357 suggests that "the local resolver security policy determines whether
358 the resolver also has to test these RRSIG RRs and how to resolve
359 conflicts if these RRSIG RRs lead to differing results." In most
360 cases, a resolver would be well advised to accept any valid RRSIG as
361 sufficient. If the first RRSIG tested fails validation, a resolver
362 would be well advised to try others, giving a successful validation
363 result if any can be validated and giving a failure only if all
364 RRSIGs fail validation.
366 If a resolver adopts a more restrictive policy, there's a danger that
367 properly-signed data might unnecessarily fail validation, perhaps
368 because of cache timing issues. Furthermore, certain zone management
369 techniques, like the Double Signature Zone-signing Key Rollover
370 method described in section 4.2.1.2 of [RFC4641] might not work
373 4.5. Key Tag Calculation
375 [RFC4034] Appendix B.1 incorrectly defines the Key Tag field
376 calculation for algorithm 1. It correctly says that the Key Tag is
377 the most significant 16 of the least significant 24 bits of the
378 public key modulus. However, [RFC4034] then goes on to incorrectly
379 say that this is 4th to last and 3rd to last octets of the public key
380 modulus. It is, in fact, the 3rd to last and 2nd to last octets.
382 4.6. Setting the DO Bit on Replies
384 As stated in [RFC3225], the DO bit of the query MUST be copied in the
385 response. At least one implementation has done something different,
386 so it may be wise for resolvers to be liberal in what they accept.
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396 4.7. Setting the AD Bit on Queries
398 The use of the AD bit in the query was previously undefined. This
399 document defines it as a signal indicating that the requester
400 understands and is interested in the value of the AD bit in the
401 response. This allows a requestor to indicate that it understands
402 the AD bit without also requesting DNSSEC data via the DO bit.
404 4.8. Setting the AD Bit on Replies
406 Section 3.2.3 of [RFC4035] describes under which conditions a
407 validating resolver should set or clear the AD bit in a response. In
408 order to protect legacy stub resolvers and middleboxes, validating
409 resolvers SHOULD only set the AD bit when a response both meets the
410 conditions listed in RFC 4035, section 3.2.3, and the request
411 contained either a set DO bit or a set AD bit.
413 4.9. Setting the CD bit on Requests
415 When processing a request with the CD bit set, a resolver SHOULD
416 attempt to return all responsive data, even data that has failed
417 DNSSEC validation. RFC4035 section 3.2.2 requires a resolver
418 processing a request with the CD bit set to set the CD bit on its
421 The guidance in RFC4035 is ambiguous about what to do when a cached
422 response was obtained with the CD bit not set. In the typical case,
423 no new query is required, nor does the cache need to track the state
424 of the CD bit used to make a given query. The problem arises when
425 the cached response is a server failure (RCODE 2), which may indicate
426 that the requested data failed DNSSEC validation at an upstream
427 validating resolver. (RFC2308 permits caching of server failures for
428 up to five minutes.) In these cases, a new query with the CD bit set
431 For efficiency, a validator may wish to set the CD bit on all
432 upstream queries when it has a trust anchor at or above the QNAME
433 (and thus can reasonably expect to be able to validate the response).
435 4.10. Nested Trust Anchors
437 A DNSSEC validator may be configured such that, for a given response,
438 more than one trust anchor could be used to validate the chain of
439 trust to the response zone. For example, imagine a validator
440 configured with trust anchors for "example." and "zone.example."
441 When the validator is asked to validate a response to
442 "www.sub.zone.example.", either trust anchor could apply.
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452 When presented with this situation, DNSSEC validators have a choice
453 of which trust anchor(s) to use. Which to use is a matter of
454 implementation choice. It is possible and perhaps advisable to
455 expose the choice of policy as a configuration option. The rest of
456 this section discusses some possible policies. As a default, we
457 suggest that validators implement the "Accept Any Success" policy
458 described below in Section 4.10.2 while exposing other policies as
459 configuration options.
461 4.10.1. Closest Encloser
463 One policy is to choose the trust anchor closest to the QNAME of the
464 response. In our example, that would be the "zone.example." trust
467 This policy has the advantage of allowing the operator to trivially
468 override a parent zone's trust anchor with one that the operator can
469 validate in a stronger way, perhaps because the resolver operator is
470 affiliated with the zone in question. This policy also minimizes the
471 number of public key operations needed, which may be of benefit in
472 resource-constrained environments.
474 This policy has the disadvantage of possibly giving the user some
475 unexpected and unnecessary validation failures when sub-zone trust
476 anchors are neglected. As a concrete example, consider a validator
477 that configured a trust anchor for "zone.example." in 2009 and one
478 for "example." in 2011. In 2012, "zone.example." rolls its KSK and
479 updates its DS records, but the validator operator doesn't update its
480 trust anchor. With the "closest encloser" policy, the validator gets
483 4.10.2. Accept Any Success
485 Another policy is to try all applicable trust anchors until one gives
486 a validation result of Secure, in which case the final validation
487 result is Secure. If and only if all applicable trust anchors give a
488 result of Insecure, the final validation result is Insecure. If one
489 or more trust anchors lead to a Bogus result and there is no Secure
490 result, then the final validation result is Bogus.
492 This has the advantage of causing the fewer validation failures,
493 which may deliver a better user experience. If one trust anchor is
494 out of date (as in our above example), the user may still be able to
495 get a Secure validation result (and see DNS responses).
497 This policy has the disadvantage of making the validator subject to
498 compromise of the weakest of these trust anchors while making its
499 relatively painless to keep old trust anchors configured in
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510 4.10.3. Preference Based on Source
512 When the trust anchors have come from different sources (e.g.
513 automated updates ([RFC5011]), one or more DLV registries
514 ([RFC5074]), and manually configured), a validator may wish to choose
515 between them based on the perceived reliability of those sources.
516 The order of precedence might be exposed as a configuration option.
518 For example, a validator might choose to prefer trust anchors found
519 in a DLV registry over those manually configured on the theory that
520 the manually configured ones will not be as aggressively maintained.
522 Conversely, a validator might choose to prefer manually configured
523 trust anchors over those obtained from a DLV registry on the theory
524 that the manually configured ones have been more carefully
527 Or the validator might do something more complicated: prefer a sub-
528 set of manually configured trust anchors (based on a configuration
529 option), then trust anchors that have been updated using the RFC5011
530 mechanism, then trust anchors from one DLV registry, then trust
531 anchors from a different DLV registry, then the rest of the manually
532 configured trust anchors.
535 5. Minor Corrections and Clarifications
537 5.1. Finding Zone Cuts
539 Appendix C.8 of [RFC4035] discusses sending DS queries to the servers
540 for a parent zone. To do that, a resolver may first need to apply
541 special rules to discover what those servers are.
543 As explained in Section 3.1.4.1 of [RFC4035], security-aware name
544 servers need to apply special processing rules to handle the DS RR,
545 and in some situations the resolver may also need to apply special
546 rules to locate the name servers for the parent zone if the resolver
547 does not already have the parent's NS RRset. Section 4.2 of
548 [RFC4035] specifies a mechanism for doing that.
550 5.2. Clarifications on DNSKEY Usage
552 Questions of the form "can I use a different DNSKEY for signing this
553 RRset" have occasionally arisen.
555 The short answer is "yes, absolutely". You can even use a different
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564 DNSKEY for each RRset in a zone, subject only to practical limits on
565 the size of the DNSKEY RRset. However, be aware that there is no way
566 to tell resolvers what a particularly DNSKEY is supposed to be used
567 for -- any DNSKEY in the zone's signed DNSKEY RRset may be used to
568 authenticate any RRset in the zone. For example, if a weaker or less
569 trusted DNSKEY is being used to authenticate NSEC RRsets or all
570 dynamically updated records, that same DNSKEY can also be used to
571 sign any other RRsets from the zone.
573 Furthermore, note that the SEP bit setting has no effect on how a
574 DNSKEY may be used -- the validation process is specifically
575 prohibited from using that bit by [RFC4034] section 2.1.2. It is
576 possible to use a DNSKEY without the SEP bit set as the sole secure
577 entry point to the zone, yet use a DNSKEY with the SEP bit set to
578 sign all RRsets in the zone (other than the DNSKEY RRset). It's also
579 possible to use a single DNSKEY, with or without the SEP bit set, to
580 sign the entire zone, including the DNSKEY RRset itself.
582 5.3. Errors in Examples
584 The text in [RFC4035] Section C.1 refers to the examples in B.1 as
585 "x.w.example.com" while B.1 uses "x.w.example". This is painfully
586 obvious in the second paragraph where it states that the RRSIG labels
587 field value of 3 indicates that the answer was not the result of
588 wildcard expansion. This is true for "x.w.example" but not for
589 "x.w.example.com", which of course has a label count of 4
590 (antithetically, a label count of 3 would imply the answer was the
591 result of a wildcard expansion).
593 The first paragraph of [RFC4035] Section C.6 also has a minor error:
594 the reference to "a.z.w.w.example" should instead be "a.z.w.example",
595 as in the previous line.
597 5.4. Errors in RFC 5155
599 A NSEC3 record that matches an Empty Non-Terminal effectively has no
600 type associated with it. This NSEC3 record has an empty type bit
601 map. Section 3.2.1 of [RFC5155] contains the statement:
603 Blocks with no types present MUST NOT be included.
605 However, the same section contains a regular expression:
607 Type Bit Maps Field = ( Window Block # | Bitmap Length | Bitmap )+
609 The plus sign in the regular expression indicates that there is one
610 or more of the preceding element. This means that there must be at
611 least one window block. If this window block has no types, it
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620 contradicts with the first statement. Therefore, the correct text in
621 RFC 5155 3.2.1 should be:
623 Type Bit Maps Field = ( Window Block # | Bitmap Length | Bitmap )*
626 6. IANA Considerations
628 This document specifies no IANA Actions.
631 7. Security Considerations
633 This document adds two cryptographic features to the core DNSSEC
634 protocol. Additionally, it addresses some ambiguities and omissions
635 in the core DNSSEC documents that, if not recognized and addressed in
636 implementations, could lead to security failures. In particular, the
637 validation algorithm clarifications in Section 3 are critical for
638 preserving the security properties DNSSEC offers. Furthermore,
639 failure to address some of the interoperability concerns in Section 4
640 could limit the ability to later change or expand DNSSEC, including
641 adding new algorithms.
646 8.1. Normative References
648 [RFC1034] Mockapetris, P., "Domain names - concepts and facilities",
649 STD 13, RFC 1034, November 1987.
651 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
652 Requirement Levels", BCP 14, RFC 2119, March 1997.
654 [RFC3225] Conrad, D., "Indicating Resolver Support of DNSSEC",
655 RFC 3225, December 2001.
657 [RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S.
658 Rose, "DNS Security Introduction and Requirements",
659 RFC 4033, March 2005.
661 [RFC4034] Arends, R., Austein, R., Larson, M., Massey, D., and S.
662 Rose, "Resource Records for the DNS Security Extensions",
663 RFC 4034, March 2005.
665 [RFC4035] Arends, R., Austein, R., Larson, M., Massey, D., and S.
666 Rose, "Protocol Modifications for the DNS Security
667 Extensions", RFC 4035, March 2005.
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673 Internet-Draft DNSSECbis Implementation Notes March 2010
676 [RFC4509] Hardaker, W., "Use of SHA-256 in DNSSEC Delegation Signer
677 (DS) Resource Records (RRs)", RFC 4509, May 2006.
679 [RFC5155] Laurie, B., Sisson, G., Arends, R., and D. Blacka, "DNS
680 Security (DNSSEC) Hashed Authenticated Denial of
681 Existence", RFC 5155, March 2008.
683 [RFC5702] Jansen, J., "Use of SHA-2 Algorithms with RSA in DNSKEY
684 and RRSIG Resource Records for DNSSEC", RFC 5702,
687 8.2. Informative References
689 [RFC3755] Weiler, S., "Legacy Resolver Compatibility for Delegation
690 Signer (DS)", RFC 3755, May 2004.
692 [RFC4641] Kolkman, O. and R. Gieben, "DNSSEC Operational Practices",
693 RFC 4641, September 2006.
695 [RFC4955] Blacka, D., "DNS Security (DNSSEC) Experiments", RFC 4955,
698 [RFC5011] StJohns, M., "Automated Updates of DNS Security (DNSSEC)
699 Trust Anchors", RFC 5011, September 2007.
701 [RFC5074] Weiler, S., "DNSSEC Lookaside Validation (DLV)", RFC 5074,
705 Appendix A. Acknowledgments
707 The editors would like the thank Rob Austein for his previous work as
708 an editor of this document.
710 The editors are extremely grateful to those who, in addition to
711 finding errors and omissions in the DNSSECbis document set, have
712 provided text suitable for inclusion in this document.
714 The lack of specificity about handling private algorithms, as
715 described in Section 4.3, and the lack of specificity in handling ANY
716 queries, as described in Section 3.2, were discovered by David
719 The error in algorithm 1 key tag calculation, as described in
720 Section 4.5, was found by Abhijit Hayatnagarkar. Donald Eastlake
721 contributed text for Section 4.5.
723 The bug relating to delegation NSEC RR's in Section 3.1 was found by
727 Weiler & Blacka Expires September 9, 2010 [Page 13]
729 Internet-Draft DNSSECbis Implementation Notes March 2010
732 Roy Badami. Roy Arends found the related problem with DNAME.
734 The errors in the [RFC4035] examples were found by Roy Arends, who
735 also contributed text for Section 5.3 of this document.
737 The editors would like to thank Alfred Hoenes, Ed Lewis, Danny Mayer,
738 Olafur Gudmundsson, Suzanne Woolf, and Scott Rose for their
739 substantive comments on the text of this document.
746 7110 Samuel Morse Drive
747 Columbia, Maryland 21046
750 Email: weiler@tislabs.com
755 21345 Ridgetop Circle
759 Email: davidb@verisign.com
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