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ops SIDROPS security cryptography X.509 This document specifies a Canonical Cache Representation (CCR) content type for use with the Resource Public Key Infrastructure (RPKI). CCR is a DER-encoded data interchange format which can be used to represent various aspects of the state of a validated cache at a particular point in time. The CCR profile is a compact and versatile format well-suited for a diverse set of applications such as audit trail keeping, validated payload dissemination, and analytics pipelines.

Introduction This document specifies a Canonical Cache Representation (CCR) content type for use with the Resource Public Key Infrastructure (RPKI). A validated cache contains all RPKI objects that the Relying Party (RP) has verified to be valid according to the rules for validation (see , , ). CCR is a data interchange format using Distinguished Encoding Rules (DER, ) which can be used to represent various aspects of the state of a validated cache at a particular point in time. The CCR profile is a compact and versatile format well-suited for a diverse set of applications such as audit record keeping, validated payload dissemination, and analytics pipelines. The format was primarily designed to support comparative analysis of uniformities and differences among multiple RP instances using different RPKI transport protocols (such as , , and ).

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 when, and only when, they appear in all capitals, as shown here.

The Canonical Cache Representation content type The contentType for a CCR currently is defined as id-ct-rpkiCanonicalCacheRepresentation, with Object Identifier (OID) 1.3.6.1.4.1.41948.825. Note: as part of the standardization process, the aforementioned contentType value should be changed from its current Private Enterprise Number () to an OID assigned by IANA.

The Canonical Cache Representation content The content of a Canonical Cache Representation is formally defined as follows: RpkiCanonicalCacheRepresentation-2025 { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs9(9) smime(16) mod(0) id-mod-rpkiCCR-2025(TBD) } DEFINITIONS EXPLICIT TAGS ::= BEGIN IMPORTS CONTENT-TYPE, Digest, DigestAlgorithmIdentifier, SubjectKeyIdentifier FROM CryptographicMessageSyntax-2010 -- in [RFC6268] { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) modules(0) id-mod-cms-2009(58) } -- in [draft-spaghetti-sidrops-rpki-erik-protocol-01] ManifestRef FROM RpkiErikPartition-2025 { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs9(9) smime(16) mod(0) id-mod-rpkiErikPartition-2025(TBD) } ASID, ROAIPAddressFamily FROM RPKI-ROA-2023 -- in [RFC9582] { so(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs9(9) smime(16) mod(0) id-mod-rpkiROA-2023(75) } ; ct-rpkiCanonicalCacheRepresentation CONTENT-TYPE ::= { TYPE RpkiCanonicalCacheRepresentation IDENTIFIED BY id-ct-rpkiCanonicalCacheRepresentation } id-ct-rpkiCanonicalCacheRepresentation OBJECT IDENTIFIER ::= { iso(1) identified-organization(3) dod(6) internet(1) private(4) enterprise(1) snijders(41948) ccr(825) } RpkiCanonicalCacheRepresentation ::= SEQUENCE { version [0] INTEGER DEFAULT 0, hashAlg DigestAlgorithmIdentifier, producedAt GeneralizedTime, mfts [1] ManifestState OPTIONAL, vrps [2] ROAPayloadState OPTIONAL, vaps [3] ASPAPayloadState OPTIONAL, tas [4] TrustAnchorState OPTIONAL, ... } -- at least one of mfts, vrps, vaps, or tas MUST be present ( WITH COMPONENTS { ..., mfts PRESENT } | WITH COMPONENTS { ..., vrps PRESENT } | WITH COMPONENTS { ..., vaps PRESENT } | WITH COMPONENTS { ..., tas PRESENT } ) ManifestState ::= SEQUENCE { mftrefs SEQUENCE OF ManifestRef, mostRecentUpdate GeneralizedTime, hash Digest } ROAPayloadState ::= SEQUENCE { rps SEQUENCE OF ROAPayloadSet, hash Digest } ROAPayloadSet ::= SEQUENCE { asID ASID, ipAddrBlocks SEQUENCE (SIZE(1..2)) OF ROAIPAddressFamily } ASPAPayloadState ::= SEQUENCE { aps SEQUENCE OF ASPAPayloadSet, hash Digest } ASPAPayloadSet ::= SEQUENCE { customerASID ASID providers SEQUENCE (SIZE(1..MAX)) OF ASID } TrustAnchorState ::= SEQUENCE { skis SEQUENCE (SIZE(1..MAX)) OF SubjectKeyIdentifier, hash Digest } END

version The version field contains the format version for the RpkiCanonicalCacheRepresentation structure, in this version of the specification it MUST be 0.

hashAlg The hashAlg field specifies the algorithm used to construct the message digests. This profile uses SHA-256 , therefore the OID MUST be 2.16.840.1.101.3.4.2.1.

producedAt The producedAt field contains a GeneralizedTime and indicates the moment in time the CCR was generated.

State aspect fields Each CCR contains one or more fields representing particular aspects of the cache's state. Implementers should note the ellipsis extension marker in the RpkiCanonicalCacheRepresentation ASN.1 notation and anticipate future changes as new signed object types are standardized. Each state aspect generally consists of a sequence of details extracted from RPKI Objects of a specific type, along with a digest computed by hashing the aforementioned DER-encoded sequence, optionally including some metadata.

ManifestState An instance of ManifestState represents the set of valid, current Manifests () in the cache. It contains three fields: The mftrefs field contains a SEQUENCE of ManifestRef structures (see ) sorted in ascending order by hash value. The hash value in each instance of ManifestRef MUST be unique with respect to the other instances of ManifestRef. The mostRecentUpdate is a metadata field which contains the most recent thisUpdate amongst all Manifests. If the mftrefs field contains an empty sequence, the mostRecentUpdate MUST be set to the POSIX Epoch ("19700101000000Z"). The hash field contains a message digest computed using the mftrefs value (encoded in DER format) as input message.

ROAPayloadState An instance of ROAPayloadState contains a field named rps which represents the current set of Validated ROA Payloads () encoded as a SEQUENCE of ROAPayloadSet instances. The ROAPayloadSet structure is modeled after the RouteOriginAttestation (). The asID value in each instance of ROAPayloadSet MUST be unique with respect to other instances of ROAPayloadSet. The contents of the ipAddrBlocks field MUST appear in canonical form and ordered as defined in . The hash field contains a message digest computed using the rps value (encoded in DER format) as input message.

ASPAPayloadState An instance of ASPAPayloadState contains an aps field which represents the current set of deduplicated and merged ASPA payloads () ordered by ascending customerASID value encoded as a SEQUENCE of ASPAPayloadSet instances. The customerASID value in each instance of ASPAPayloadSet MUST be unique with respect to other instances of ASPAPayloadSet. The ASPAPayloadSet structure is modeled after the ProviderASSet (). The hash field contains a message digest computed using the aps value (encoded in DER format) as input message.

TrustAnchorState An instance of TrustAnchorState represents the set of valid Trust Anchor (TA) Certification Authority (CA) resource certificates used by the relying party when producing the CCR. The skis field contains a sequence of Subject Key Identifiers (SKI) sorted in ascending order. Each SubjectKeyIdentifier is the 160-bit SHA-1 hash of the value of the DER-encoded ASN.1 bit string of the TA's Subject Public Key, as described in . The hash field contains a message digest computed using the skis value (encoded in DER format) as input message.

Operational Considerations Comparing the ManifestState mostRecentUpdate timestamp value with the producedAt timestamp might help offer insight into the timing and propagation delays of the RPKI supply chain. Given the absence of public keys and fairly repetitive content in RPKI AccessDescription instances, it should be noted CCR content compresses well.

Verifying CCR file integrity The integrity of a CCR object can be checked by confirming whether the hash values embedded inside state aspects match the computed hash value of the respective state aspect payload structure.

Security Considerations CCR objects are not signed objects.

IANA Considerations

SMI Security for S/MIME CMS Content Type (1.2.840.113549.1.9.16.1) NOTE: unclear which registry this actually should go... IANA is requested to allocate the following in the "SMI Security for S/MIME CMS Content Type (1.2.840.113549.1.9.16.1)" registry:

Decimal	Description	References
TBD	id-ct-rpkiCanonicalCacheRepresentation	draft-spaghetti-sidrops-rpki-ccr

RPKI Repository Name Schemes IANA is requested to add the Canonical Cache Representation file extension to the "RPKI Repository Name Schemes" registry as follows:

Filename Extension	RPKI Object	Reference
.ccr	Canonical Cache Representation	draft-spaghetti-sidrops-rpki-ccr

SMI Security for S/MIME Module Identifier (1.2.840.113549.1.9.16.0) IANA is requested to allocate the following in the "SMI Security for S/MIME Module Identifier (1.2.840.113549.1.9.16.0)" registry:

Decimal	Description	References
TBD	id-mod-rpkiCCR-2025	draft-spaghetti-sidrops-rpki-ccr

Media Types IANA is requested to register the media type "application/rpki-ccr" in the "Media Types" registry as follows:

Canonical Cache Representation Media Type

Type name:

application

Subtype name:

rpki-ccr

Required parameters:

N/A

Optional parameters:

N/A

Encoding considerations:

binary

Security considerations:

This media type contains no active content.

Interoperability considerations:

N/A

Published specification:

draft-spaghetti-sidrops-rpki-ccr

Applications that use this media type:

RPKI operators

Fragment identifier considerations:

N/A

Additional information:

Content:

This media type is a RPKI Canonical Cache Representation object, as defined in draft-spaghetti-sidrops-rpki-ccr.

Magic number(s):

N/A

File extension(s):

.ccr

Macintosh file type code(s):

N/A

Person & email address to contact for further information:

Job Snijders (job@sobornost.net)

Intended usage:

COMMON

Restrictions on usage:

N/A

Author:

Job Snijders (job@sobornost.net)

Change controller:

IETF

References Normative References In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. This document defines a profile for the structure of the Resource Public Key Infrastructure (RPKI) distributed repository. Each individual repository publication point is a directory that contains files that correspond to X.509/PKIX Resource Certificates, Certificate Revocation Lists and signed objects. This profile defines the object (file) naming scheme, the contents of repository publication points (directories), and a suggested internal structure of a local repository cache that is intended to facilitate synchronization across a distributed collection of repository publication points and to facilitate certification path construction. [STANDARDS-TRACK] This document defines a standard profile for X.509 certificates for the purpose of supporting validation of assertions of "right-of-use" of Internet Number Resources (INRs). The certificates issued under this profile are used to convey the issuer's authorization of the subject to be regarded as the current holder of a "right-of-use" of the INRs that are described in the certificate. This document contains the normative specification of Certificate and Certificate Revocation List (CRL) syntax in the Resource Public Key Infrastructure (RPKI). This document also specifies profiles for the format of certificate requests and specifies the Relying Party RPKI certificate path validation procedure. [STANDARDS-TRACK] This document defines a generic profile for signed objects used in the Resource Public Key Infrastructure (RPKI). These RPKI signed objects make use of Cryptographic Message Syntax (CMS) as a standard encapsulation format. [STANDARDS-TRACK] To help reduce well-known threats against BGP including prefix mis- announcing and monkey-in-the-middle attacks, one of the security requirements is the ability to validate the origination Autonomous System (AS) of BGP routes. More specifically, one needs to validate that the AS number claiming to originate an address prefix (as derived from the AS_PATH attribute of the BGP route) is in fact authorized by the prefix holder to do so. This document describes a simple validation mechanism to partially satisfy this requirement. [STANDARDS-TRACK] RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings. 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. This document defines a standard profile for Route Origin Authorizations (ROAs). A ROA is a digitally signed object that provides a means of verifying that an IP address block holder has authorized an Autonomous System (AS) to originate routes to one or more prefixes within the address block. This document obsoletes RFC 6482. Yandex JetLend Internet Initiative Japan Vigil Security, LLC Workonline This document defines a Cryptographic Message Syntax (CMS) protected content type for Autonomous System Provider Authorization (ASPA) objects for use with the Resource Public Key Infrastructure (RPKI). An ASPA is a digitally signed object through which the issuer (the holder of an Autonomous System identifier), can authorize one or more other Autonomous Systems (ASes) as its upstream providers. When validated, an ASPA's eContent can be used for detection and mitigation of route leaks. This document specifies the Erik Synchronization Protocol for use with the Resource Public Key Infrastructure (RPKI). Erik Synchronization can be characterized as a data replication system using Merkle trees, a content-addressable naming scheme, concurrency control using monotonically increasing sequence numbers, and HTTP transport. Relying Parties can combine information retrieved via Erik Synchronization with other RPKI transport protocols. The protocol's design is intended to be efficient, fast, and easy to implement. National Institute of Standards and Technology ITU-T Informative References This document specifies the rsync Uniform Resource Identifier (URI) scheme. This document is not an Internet Standards Track specification; it is published for informational purposes. In the Resource Public Key Infrastructure (RPKI), Certificate Authorities (CAs) publish certificates, including end-entity certificates, Certificate Revocation Lists (CRLs), and RPKI signed objects to repositories. Relying Parties retrieve the published information from those repositories. This document specifies a new RPKI Repository Delta Protocol (RRDP) for this purpose. RRDP was specifically designed for scaling. It relies on an Update Notification File which lists the current Snapshot and Delta Files that can be retrieved using HTTPS (HTTP over Transport Layer Security (TLS)), and it enables the use of Content Distribution Networks (CDNs) or other caching infrastructures for the retrieval of these files. This document describes how Private Enterprise Numbers (PENs) are registered by IANA. It shows how to request a new PEN and how to modify a current PEN. It also gives a brief overview of PEN uses.

Acknowledgements The authors wish to thank for their generous feedback on this specification.

For a more elaborate example based on the global RPKI, see the URL in . The following Base64-encoded blob contains a CCR listing 7 Manifest references, 5 Trust Anchor key identifiers, 0 ROA payloadsets and 0 ASPA payloadsets. It decodes as following:

Implementation status This section records the status of known implementations of the protocol defined by this specification at the time of posting of this Internet-Draft, and is based on a proposal described in RFC 7942. The description of implementations in this section is intended to assist the IETF in its decision processes in progressing drafts to RFCs. Please note that the listing of any individual implementation here does not imply endorsement by the IETF. Furthermore, no effort has been spent to verify the information presented here that was supplied by IETF contributors. This is not intended as, and must not be construed to be, a catalog of available implementations or their features. Readers are advised to note that other implementations may exist. According to RFC 7942, "this will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature. It is up to the individual working groups to use this information as they see fit".

• Example .ccr files were created by Job Snijders. A current example CCR (regenerated every few minutes) is available here:
• A CCR serializer and deserializer implementation based on was provided by Job Snijders.