Internet Engineering Task Force (IETF) R. Austein

Internet Engineering Task Force (IETF) R. Austein
Request for Comments: 9286 Arrcus, Inc.
Obsoletes: 6486 G. Huston
Category: Standards Track APNIC
ISSN: 2070-1721 S. Kent
Independent
M. Lepinski
New College Florida
June 2022

Manifests for the Resource Public Key Infrastructure (RPKI)

Abstract

This document defines a "manifest" for use in the Resource Public Key
Infrastructure (RPKI). A manifest is a signed object (file) that
contains a listing of all the signed objects (files) in the
repository publication point (directory) associated with an authority
responsible for publishing in the repository. For each certificate,
Certificate Revocation List (CRL), or other type of signed objects
issued by the authority that are published at this repository
publication point, the manifest contains both the name of the file
containing the object and a hash of the file content. Manifests are
intended to enable a relying party (RP) to detect certain forms of
attacks against a repository. Specifically, if an RP checks a
manifest's contents against the signed objects retrieved from a
repository publication point, then the RP can detect replay attacks,
and unauthorized in-flight modification or deletion of signed
objects. This document obsoletes RFC 6486.

Status of This Memo

This is an Internet Standards Track document.

This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.

Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc9286.

Copyright Notice

Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved.

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in the Revised BSD License.

Table of Contents

1. Introduction
1.1. Requirements Language
2. Manifest Scope
3. Manifest Signing
4. Manifest Definition
4.1. eContentType
4.2. eContent
4.2.1. Manifest
4.2.2. Names in FileAndHash Objects
4.3. Content-Type Attribute
4.4. Manifest Validation
5. Manifest Generation
5.1. Manifest Generation Procedure
5.2. Considerations for Manifest Generation
6. Relying Party Processing of Manifests
6.1. Manifest Processing Overview
6.2. Acquiring a Manifest for a CA
6.3. Detecting Stale and/or Prematurely Issued Manifests
6.4. Acquiring Files Referenced by a Manifest
6.5. Matching File Names and Hashes
6.6. Failed Fetches
7. Publication Repositories
8. Security Considerations
9. IANA Considerations
10. References
10.1. Normative References
10.2. Informative References
Appendix A. ASN.1 Module
Appendix B. Changes since RFC 6486
Acknowledgements
Authors' Addresses

1. Introduction

The Resource Public Key Infrastructure (RPKI) [RFC6480] makes use of
a distributed repository system [RFC6481] to make available a variety
of objects needed by relying parties (RPs). Because all of the
objects stored in the repository system are digitally signed by the
entities that created them, attacks that modify these published
objects are detectable by RPs. However, digital signatures alone
provide no protection against attacks that substitute "stale"
versions of signed objects (i.e., objects that were valid and have
not yet expired, but have since been superseded), or in-flight
attacks that remove an object that should be present in the
repository. To assist in the detection of such attacks, RPKI
repository systems make use of a signed object called a "manifest".

A manifest is a signed object that enumerates all the signed objects
(files) in the repository publication point (directory) that are
associated with an authority responsible for publishing at that
publication point. Each manifest contains both the name of the file
containing the object and a hash of the file content, for every
signed object issued by an authority that is published at the
authority's repository publication point. A manifest is intended to
allow an RP to detect unauthorized object removal or the substitution
of stale versions of objects at a publication point. A manifest also
is intended to allow an RP to detect similar outcomes that may result
from an on-path attack during the retrieval of objects from the
repository. Manifests are intended to be used in Certification
Authority (CA) publication points in repositories (directories
containing files that are subordinate certificates and Certificate
Revocation Lists (CRLs) issued by this CA and other signed objects
that are verified by End-Entity (EE) certificates issued by this CA).

Manifests are modeled on CRLs, as the issues involved in detecting
stale manifests and potential attacks using manifest replays, etc.,
are similar to those for CRLs. The syntax of the manifest payload
differs from CRLs, since RPKI repositories contain objects not
covered by CRLs, e.g., digitally signed objects, such as Route Origin
Authorizations (ROAs) [RFC6482].

This document obsoletes [RFC6486].

1.1. Requirements Language

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.

2. Manifest Scope

A manifest associated with a CA's repository publication point
contains a list of:

* the set of (non-expired, non-revoked) certificates issued and
published by this CA,

* the most recent CRL issued by this CA, and

* all published signed objects that are verifiable using EE
certificates [RFC6487] issued by this CA (other than the manifest
itself).

Every RPKI signed object includes, in the Cryptographic Message
Syntax (CMS) [RFC5652] wrapper of the object, the EE certificate used
to verify it [RFC6488]. Thus, there is no requirement to separately
publish that EE certificate at the CA's repository publication point.

Where multiple CA instances share a common publication point, as can
occur when a CA performs a key-rollover operation [RFC6489], the
repository publication point will contain multiple manifests. In
this case, each manifest describes only the collection of published
products of its associated CA instance.

3. Manifest Signing

A CA's manifest is verified using an EE certificate. The
SubjectInfoAccess (SIA) field of this EE certificate contains the
accessMethod Object Identifier (OID) of id-ad-signedObject.

The CA MUST sign only one manifest with each generated private key
and MUST generate a new key pair for each new version of the
manifest. An associated EE certificate used in this fashion is
termed a "one-time-use" EE certificate (see Section 3 of [RFC6487]).

4. Manifest Definition

A manifest is an RPKI signed object, as specified in [RFC6488]. The
RPKI signed object template requires specification of the following
data elements in the context of the manifest structure.

4.1. eContentType

The eContentType for a manifest is defined as id-ct-rpkiManifest and
has the numerical OID of 1.2.840.113549.1.9.16.1.26.

id-smime OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840)
rsadsi(113549) pkcs(1) pkcs9(9) 16 }

id-ct OBJECT IDENTIFIER ::= { id-smime 1 }

id-ct-rpkiManifest OBJECT IDENTIFIER ::= { id-ct 26 }

4.2. eContent

The content of a manifest is ASN.1 encoded using the Distinguished
Encoding Rules (DER) [X.690]. The content of a manifest is defined
as follows:

Manifest ::= SEQUENCE {
version [0] INTEGER DEFAULT 0,
manifestNumber INTEGER (0..MAX),
thisUpdate GeneralizedTime,
nextUpdate GeneralizedTime,
fileHashAlg OBJECT IDENTIFIER,
fileList SEQUENCE SIZE (0..MAX) OF FileAndHash
}

FileAndHash ::= SEQUENCE {
file IA5String,
hash BIT STRING
}

4.2.1. Manifest

The manifestNumber, thisUpdate, and nextUpdate fields are modeled
after the corresponding fields in X.509 CRLs (see [RFC5280]).
Analogous to CRLs, a manifest is nominally current until the time
specified in nextUpdate or until a manifest is issued with a greater
manifest number, whichever comes first.

Because a "one-time-use" EE certificate is employed to verify a
manifest, the EE certificate MUST be issued with a validity period
that coincides with the interval from thisUpdate to nextUpdate in the
manifest, to prevent needless growth of the CA's CRL.

The data elements of the manifest structure are defined as follows:

version:
The version number of this version of the manifest specification
MUST be 0.

manifestNumber:
This field is an integer that is incremented (by 1) each time a
new manifest is issued for a given publication point. This field
allows an RP to detect gaps in a sequence of published manifests.

As the manifest is modeled on the CRL specification, the
manifestNumber is analogous to the CRLNumber, and the guidance in
[RFC5280] for CRLNumber values is appropriate as to the range of
number values that can be used for the manifestNumber. Manifest
numbers can be expected to contain long integers. Manifest
verifiers MUST be able to process number values up to 20 octets.
Conforming manifest issuers MUST NOT use number values longer than
20 octets. The issuer MUST increase the value of this field
monotonically for each newly generated manifest. Each RP MUST
verify that a purported "new" manifest contains a higher
manifestNumber than previously validated manifests. If the
purported "new" manifest contains a manifestNumber value equal to
or lower than manifestNumber values of previously validated
manifests, the RP SHOULD use locally cached versions of objects,
as described in Section 6.6.

thisUpdate:
This field contains the time when the manifest was created. This
field has the same format constraints as specified in [RFC5280]
for the CRL field of the same name. The issuer MUST ensure that
the value of this field is more recent than any previously
generated manifest. Each RP MUST verify that this field value is
greater (more recent) than the most recent manifest it has
validated. If this field in a purported "new" manifest is smaller
(less recent) than previously validated manifests, the RP SHOULD
use locally cached versions of objects, as described in
Section 6.6.

nextUpdate:
This field contains the time at which the next scheduled manifest
will be issued. The value of nextUpdate MUST be later than the
value of thisUpdate. The specification of the GeneralizedTime
value is the same as required for the thisUpdate field.

If the authority alters any of the items that it has published in
the repository publication point, then the authority MUST issue a
new manifest. Even if no changes are made to objects at a
publication point, a new manifest MUST be issued before the
nextUpdate time. Each manifest encompasses a CRL, and the
nextUpdate field of the manifest SHOULD match that of the CRL's
nextUpdate field, as the manifest will be reissued when a new CRL
is published. When a new manifest is issued before the time
specified in nextUpdate of the current manifest, the CA MUST also
issue a new CRL that revokes the EE certificate corresponding to
the old manifest.

fileHashAlg:
This field contains the OID of the hash algorithm used to hash the
files that the authority has placed into the repository. The hash
algorithm used MUST conform to the RPKI Algorithms and Key Size
Profile specification [RFC7935].

fileList:
This field is a sequence of FileAndHash objects. There is one
FileAndHash entry for each currently valid signed object that has
been published by the authority (at this publication point). Each
FileAndHash is an ordered pair consisting of the name of the file
in the repository publication point (directory) that contains the
object in question and a hash of the file's contents.

4.2.2. Names in FileAndHash Objects

Names that appear in the fileList MUST consist of one or more
characters chosen from the set a-z, A-Z, 0-9, - (HYPHEN), or
_ (UNDERSCORE), followed by a single . (DOT), followed by a three-
letter extension. The extension MUST be one of those enumerated in
the "RPKI Repository Name Schemes" registry maintained by IANA
[IANA-NAMING].

As an example, 'vixxBTS_TVXQ-2pmGOT7.cer' is a valid file name.

The example above contains a mix of uppercase and lowercase
characters in the file name. CAs and RPs MUST be able to perform
filesystem operations in a case-sensitive, case-preserving manner.

4.3. Content-Type Attribute

The mandatory content-type attribute MUST have its attrValues field
set to the same OID as eContentType. This OID is id-ct-rpkiManifest
and has the numerical value of 1.2.840.113549.1.9.16.1.26.

4.4. Manifest Validation

To determine whether a manifest is valid, the RP MUST perform the
following checks in addition to those specified in [RFC6488]:

1. The eContentType in the EncapsulatedContentInfo is id-ad-
rpkiManifest (OID 1.2.840.113549.1.9.16.1.26).

2. The version of the rpkiManifest is 0.

3. In the rpkiManifest, thisUpdate precedes nextUpdate.

Note: Although the thisUpdate and nextUpdate fields in the manifest
eContent MUST match the corresponding fields in the CRL associated
with the manifest, RPs MUST NOT reject a manifest solely because
these fields are not identical.

If the above procedure indicates that the manifest is invalid, then
the manifest MUST be discarded and treated as though no manifest were
present.

5. Manifest Generation

5.1. Manifest Generation Procedure

For a CA publication point in the RPKI repository system, a CA MUST
perform the following steps to generate a manifest:

1. Generate a new key pair for use in a "one-time-use" EE
certificate.

2. Issue an EE certificate for this key pair. The CA MUST revoke
the EE certificate used for the manifest being replaced.

This EE certificate MUST have an SIA extension access description
field with an accessMethod OID value of id-ad-signedObject, where
the associated accessLocation references the publication point of
the manifest as an object URL. (RPs are required to verify both
of these syntactic constraints.)

This EE certificate MUST describe its Internet Number Resources
(INRs) using the "inherit" attribute, rather than an explicit
description of a resource set (see [RFC3779]). (RPs are required
to verify this.)

The validity interval of the EE certificate MUST exactly match
the thisUpdate and nextUpdate times specified in the manifest's
eContent. (An RP MUST NOT consider misalignment of the validity
interval in and of itself to be an error.)

3. The EE certificate MUST NOT be published in the authority's
repository publication point.

4. Construct the manifest content.

The manifest content is described in Section 4.2.1. The
manifest's fileList includes the file name and hash pair for each
object issued by this CA that has been published at this
repository publication point (directory). The collection of
objects to be included in the manifest includes all certificates
issued by this CA that are published at the CA's repository
publication point, the most recent CRL issued by the CA, and all
objects verified by EE certificates that were issued by this CA
that are published at this repository publication point.
(Sections 6.1 through 6.5 describe the checks that an RP MUST
perform in support of the manifest content noted here.)

Note that the manifest does not include a self reference (i.e.,
its own file name and hash), since it would be impossible to
compute the hash of the manifest itself prior to it being signed.

5. Encapsulate the manifest content using the CMS SignedData content
type (as specified in Section 4), sign the manifest using the
private key corresponding to the subject key contained in the EE
certificate, and publish the manifest in the repository system
publication point that is described by the manifest. (RPs are
required to verify the CMS signature.)

6. Because the key pair is to be used only once, the private key
associated with this key pair MUST now be destroyed.

5.2. Considerations for Manifest Generation

A new manifest MUST be issued and published before the nextUpdate
time.

An authority MUST issue a new manifest in conjunction with the
finalization of changes made to objects in the publication point. If
any named objects in the publication point are replaced, the
authority MUST ensure that the file hash for each replaced object is
updated accordingly in the new manifest. Additionally, the authority
MUST revoke the certificate associated with each replaced object
(other than a CRL), if it is not expired. An authority MAY perform a
number of object operations on a publication repository within the
scope of a repository change before issuing a single manifest that
covers all the operations within the scope of this change.
Repository operators MUST implement some form of repository update
procedure that mitigates, to the extent possible, the risk that RPs
that are performing retrieval operations on the repository are
exposed to inconsistent, transient, intermediate states during
updates to the repository publication point (directory) and the
associated manifest.

Since the manifest object URL is included in the SIA of issued
certificates, a new manifest MUST NOT invalidate the manifest object
URL of previously issued certificates. This implies that the
manifest's publication name in the repository, in the form of an
object URL, is unchanged across manifest generation cycles.

When a CA entity is performing a key rollover, the entity MAY choose
to have two CA instances simultaneously publishing into the same
repository publication point. In this case, there will be one
manifest associated with each active CA instance that is publishing
into the common repository publication point (directory).

6. Relying Party Processing of Manifests

Each RP MUST use the current manifest of a CA to control addition of
listed files to the set of signed objects the RP employs for
validating basic RPKI objects: certificates, ROAs, and CRLs. Any
files not listed on the manifest MUST NOT be used for validation of
these objects. However, files not listed on a manifest MAY be
employed to validate other signed objects, if the profile of the
object type explicitly states that such behavior is allowed (or
required). Note that relying on files not listed in a manifest may
allow an attacker to effect substitution attacks against such
objects.

As noted earlier, manifests are designed to allow an RP to detect
manipulation of repository data, errors by a CA or repository
manager, and/or active attacks on the communication channel between
an RP and a repository. Unless all of the files enumerated in a
manifest can be obtained by an RP during a fetch operation, the fetch
is considered to have failed and the RP MUST retry the fetch later.

[RFC6480] suggests (but does not mandate) that the RPKI model employ
fetches that are incremental, e.g., an RP transfers files from a
publication point only if they are new/changed since the previous,
successful fetch represented in the RP's local cache. This document
avoids language that relies on details of the underlying file
transfer mechanism employed by an RP and a publication point to
effect this operation. Thus, the term "fetch" refers to an operation
that attempts to acquire the full set of files at a publication
point, consistent with the id-ad-rpkiManifest URI extracted from a CA
certificate's SIA (see below).

If a fetch fails, it is assumed that a subsequent fetch will resolve
problems encountered during the fetch. Until such time as a
successful fetch is executed, an RP SHOULD use cached data from a
previous, successful fetch. This response is intended to prevent an
RP from misinterpreting data associated with a publication point and
thus possibly treating invalid routes as valid, or vice versa.

The processing described below is designed to cause all RPs with
access to the same local cache and RPKI repository data to acquire
the same set of validated repository files. It does not ensure that
the RPs will achieve the same results with regard to validation of
RPKI data, since that depends on how each RP resolves any conflicts
that may arise in processing the retrieved files. Moreover, in
operation, different RPs will access repositories at different times,
and some RPs may experience local cache failures, so there is no
guarantee that all RPs will achieve the same results with regard to
acquisition or validation of RPKI data.

Note also that there is a "chicken and egg" relationship between the
manifest and the CRL for a given CA instance. If the EE certificate
for the current manifest is revoked, i.e., it appears in the current
CRL, then the CA or publication point manager has made a serious
error. In this case, the fetch has failed; proceed to Section 6.6.
Similarly, if the CRL is not listed on a valid, current manifest,
acquired during a fetch, the fetch has failed; proceed to
Section 6.6, because the CRL is considered missing.

6.1. Manifest Processing Overview

For a given publication point, an RP MUST perform a series of tests
to determine which signed object files at the publication point are
acceptable. The tests described below (Sections 6.2 through 6.5) are
to be performed using the manifest identified by the id-ad-
rpkiManifest URI extracted from a CA certificate's SIA. All of the
files referenced by the manifest MUST be located at the publication
point specified by the id-ad-caRepository URI from the (same) CA
certificate's SIA. The manifest and the files it references MUST
reside at the same publication point. If an RP encounters any files
that appear on a manifest but do not reside at the same publication
point as the manifest, the RP MUST treat the fetch as failed, and a
warning MUST be issued (see Section 6.6 below).

Note that, during CA key rollover [RFC6489], signed objects for two
or more different CA instances will appear at the same publication
point. Manifest processing is to be performed separately for each CA
instance, guided by the SIA id-ad-rpkiManifest URI in each CA
certificate.

6.2. Acquiring a Manifest for a CA

The RP MUST fetch the manifest identified by the SIA id-ad-
rpkiManifest URI in the CA certificate. If an RP cannot retrieve a
manifest using this URI or if the manifest is not valid
(Section 4.4), an RP MUST treat this as a failed fetch; proceed to
Section 6.6. Otherwise, proceed to Section 6.3.

6.3. Detecting Stale and/or Prematurely Issued Manifests

The RP MUST check that the current time (translated to UTC) is
between thisUpdate and nextUpdate. If the current time lies within
this interval, proceed to Section 6.4. If the current time is
earlier than thisUpdate, the CA may have made an error or the RP's
local notion of time may be in error. The RP MUST treat this as a
failed fetch; proceed to Section 6.6. If the current time is later
than nextUpdate, then the manifest is stale; the RP MUST treat this
as a failed fetch. Proceed to Section 6.6. Otherwise, proceed to
Section 6.4.

6.4. Acquiring Files Referenced by a Manifest

The RP MUST acquire all of the files enumerated in the manifest
(fileList) from the publication point. If there are files listed in
the manifest that cannot be retrieved from the publication point, the
RP MUST treat this as a failed fetch. Proceed to Section 6.6.
Otherwise, proceed to Section 6.5.

6.5. Matching File Names and Hashes

The RP MUST verify that the hash value of each file listed in the
manifest matches the value obtained by hashing the file acquired from
the publication point. If the computed hash value of a file listed
on the manifest does not match the hash value contained in the
manifest, then the fetch has failed, and the RP MUST respond
accordingly. Proceed to Section 6.6.

6.6. Failed Fetches

If a fetch fails for any of the reasons cited in Sections 6.2 through
6.5, the RP MUST issue a warning indicating the reason(s) for
termination of processing with regard to this CA instance. It is
RECOMMENDED that a human operator be notified of this warning.

Termination of processing means that the RP SHOULD continue to use
cached versions of the objects associated with this CA instance,
until such time as they become stale or they can be replaced by
objects from a successful fetch. This implies that the RP MUST NOT
try to acquire and validate subordinate signed objects, e.g.,
subordinate CA certificates, until the next interval when the RP is
scheduled to fetch and process data for this CA instance.

7. Publication Repositories

The RPKI publication system model requires that every publication
point be associated with one or more CAs and be non-empty. Upon
creation of the publication point associated with a CA, the CA MUST
create and publish a manifest as well as a CRL. A CA's manifest will
always contain at least one entry, i.e., a CRL issued by the CA
[RFC6481], corresponding to the scope of this manifest.

Every published signed object in the RPKI [RFC6488] is published in
the repository publication point of the CA that issued the EE
certificate, and is listed in the manifest associated with that CA
certificate.

8. Security Considerations

Manifests provide an additional level of protection for RPKI RPs.
Manifests can assist an RP in determining if a repository object has
been deleted, occluded, or otherwise removed from view, or if a
publication of a newer version of an object has been suppressed (and
an older version of the object has been substituted).

Manifests cannot repair the effects of such forms of corruption of
repository retrieval operations. However, a manifest enables an RP
to determine if a locally maintained copy of a repository is a
complete and up-to-date copy, even when the repository retrieval
operation is conducted over an insecure channel. In cases where the
manifest and the retrieved repository contents differ, the manifest
can assist in determining which repository objects form the
difference set in terms of missing, extraneous, or superseded
objects.

The signing structure of a manifest and the use of the nextUpdate
value allow an RP to determine if the manifest itself is the subject
of attempted alteration. The requirement for every repository
publication point to contain at least one manifest allows an RP to
determine if the manifest itself has been occluded from view. Such
attacks against the manifest are detectable within the time frame of
the regular schedule of manifest updates. Forms of replay attacks
within finer-grained time frames are not necessarily detectable by
the manifest structure.

9. IANA Considerations

The "RPKI Signed Objects" registry was originally created and
populated by [RFC6488]. The "RPKI Repository Name Schemes" registry
was created by [RFC6481] and created four of the initial three-letter
file name extensions. IANA has updated the reference for the
"Manifest" row in the "RPKI Signed Objects" registry to point to this
document.

IANA has also updated the following entries to refer to this document
instead of RFC 6486:

* id-mod-rpkiManifest (60) in the "SMI Security for S/MIME Module
Identifier (1.2.840.113549.1.9.16.0)" registry

* id-ct-rpkiManifest (26) in the "SMI Security for S/MIME CMS
Content Type (1.2.840.113549.1.9.16.1)" registry

* the "Security considerations" entry in the application media type
registration for rpki-manifest

No other actions are required.

10. References

10.1. Normative References

[IANA-NAMING]
IANA, "RPKI Repository Name Schemes",
<https://www.iana.org/assignments/rpki/>.

[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.

[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
<https://www.rfc-editor.org/info/rfc5280>.

[RFC6481] Huston, G., Loomans, R., and G. Michaelson, "A Profile for
Resource Certificate Repository Structure", RFC 6481,
DOI 10.17487/RFC6481, February 2012,
<https://www.rfc-editor.org/info/rfc6481>.

[RFC6482] Lepinski, M., Kent, S., and D. Kong, "A Profile for Route
Origin Authorizations (ROAs)", RFC 6482,
DOI 10.17487/RFC6482, February 2012,
<https://www.rfc-editor.org/info/rfc6482>.

[RFC6487] Huston, G., Michaelson, G., and R. Loomans, "A Profile for
X.509 PKIX Resource Certificates", RFC 6487,
DOI 10.17487/RFC6487, February 2012,
<https://www.rfc-editor.org/info/rfc6487>.

[RFC6488] Lepinski, M., Chi, A., and S. Kent, "Signed Object
Template for the Resource Public Key Infrastructure
(RPKI)", RFC 6488, DOI 10.17487/RFC6488, February 2012,
<https://www.rfc-editor.org/info/rfc6488>.

[RFC7935] Huston, G. and G. Michaelson, Ed., "The Profile for
Algorithms and Key Sizes for Use in the Resource Public
Key Infrastructure", RFC 7935, DOI 10.17487/RFC7935,
August 2016, <https://www.rfc-editor.org/info/rfc7935>.

[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.

[X.690] International Telecommunication Union, "Information
technology - ASN.1 encoding rules: Specification of Basic
Encoding Rules (BER), Canonical Encoding Rules (CER) and
Distinguished Encoding Rules (DER)", ITU-T Recommendation
X.690, February 2021,
<https://www.itu.int/rec/T-REC-X.690-202102-I/en>.

10.2. Informative References

[RFC3779] Lynn, C., Kent, S., and K. Seo, "X.509 Extensions for IP
Addresses and AS Identifiers", RFC 3779,
DOI 10.17487/RFC3779, June 2004,
<https://www.rfc-editor.org/info/rfc3779>.

[RFC5652] Housley, R., "Cryptographic Message Syntax (CMS)", STD 70,
RFC 5652, DOI 10.17487/RFC5652, September 2009,
<https://www.rfc-editor.org/info/rfc5652>.

[RFC6480] Lepinski, M. and S. Kent, "An Infrastructure to Support
Secure Internet Routing", RFC 6480, DOI 10.17487/RFC6480,
February 2012, <https://www.rfc-editor.org/info/rfc6480>.

[RFC6486] Austein, R., Huston, G., Kent, S., and M. Lepinski,
"Manifests for the Resource Public Key Infrastructure
(RPKI)", RFC 6486, DOI 10.17487/RFC6486, February 2012,
<https://www.rfc-editor.org/info/rfc6486>.

[RFC6489] Huston, G., Michaelson, G., and S. Kent, "Certification
Authority (CA) Key Rollover in the Resource Public Key
Infrastructure (RPKI)", BCP 174, RFC 6489,
DOI 10.17487/RFC6489, February 2012,
<https://www.rfc-editor.org/info/rfc6489>.

Appendix A. ASN.1 Module

RPKIManifest { iso(1) member-body(2) us(840) rsadsi(113549)
pkcs(1) pkcs9(9) smime(16) mod(0) 60 }

DEFINITIONS EXPLICIT TAGS ::=
BEGIN

-- EXPORTS ALL --

IMPORTS

CONTENT-TYPE
FROM CryptographicMessageSyntax-2010 -- in RFC 6268
{ iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
pkcs-9(9) smime(16) modules(0) id-mod-cms-2009(58) } ;

-- Manifest Content Type

ct-rpkiManifest CONTENT-TYPE ::=
{ TYPE Manifest IDENTIFIED BY id-ct-rpkiManifest }

id-smime OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs9(9) 16 }

id-ct OBJECT IDENTIFIER ::= { id-smime 1 }

id-ct-rpkiManifest OBJECT IDENTIFIER ::= { id-ct 26 }

Manifest ::= SEQUENCE {
version [0] INTEGER DEFAULT 0,
manifestNumber INTEGER (0..MAX),
thisUpdate GeneralizedTime,
nextUpdate GeneralizedTime,
fileHashAlg OBJECT IDENTIFIER,
fileList SEQUENCE SIZE (0..MAX) OF FileAndHash
}

FileAndHash ::= SEQUENCE {
file IA5String,
hash BIT STRING
}

END

Appendix B. Changes since RFC 6486

In 2019, it came to light that multiple RP implementations were in a
vulnerable position, possibly due to perceived ambiguity in the
original [RFC6486] specification. This document attempts to clarify
the innovative concept and application of RPKI manifests in light of
real-world deployment experience in the global Internet routing
system, to avoid future problematic cases.

The following list summarizes the changes between RFC 6486 and this
document:

* Forbidding "sequential-use" EE certificates and instead mandating
"one-time-use" EE certificates.

* Clarifying that manifest EE certificates are to be issued with a
validity period that coincides with the interval specified in the
manifest eContent, which coincides with the CRL's thisUpdate and
nextUpdate.

* Clarifying that the manifestNumber is monotonically incremented in
steps of 1.

* Recommending that CA issuers include the applicable CRL's
nextUpdate with the manifest's nextUpdate.

* Constraining the set of valid characters in FileAndHash file
names.

* Clarifying that an RP unable to obtain the full set of files
listed on a manifest is considered to be in a failure state, in
which case cached data from a previous attempt should be used (if
available).

* Clarifying the requirement for a current CRL to be present,
listed, and verified.

* Removing the notion of "local policy".

Acknowledgements

The authors would like to acknowledge the contributions from George
Michaelson and Randy Bush in the preparation of the manifest
specification. Additionally, the authors would like to thank Mark
Reynolds and Christopher Small for assistance in clarifying manifest
validation and RP behavior. The authors also wish to thank Tim
Bruijnzeels, Job Snijders, Oleg Muravskiy, Sean Turner, Adianto
Wibisono, Murray Kucherawy, Francesca Palombini, Roman Danyliw, Lars
Eggert, Robert Wilton, and Benjamin Kaduk for their helpful review of
this document.

Authors' Addresses

Rob Austein
Arrcus, Inc.
Email: [email protected]

Geoff Huston
APNIC
6 Cordelia St
South Brisbane QLD 4101
Australia
Email: [email protected]

Stephen Kent
Independent
Email: [email protected]

Matt Lepinski
New College Florida
5800 Bay Shore Rd.
Sarasota, FL 34243
United States of America
Email: [email protected]