Fastly

Amsterdam Netherlands job@fastly.com

New College Florida

mlepinski@ncf.edu

Raytheon

derrick.kong@raytheon.com

Independent

kent@alum.mit.edu

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. 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.

Introduction The primary purpose of the Resource Public Key Infrastructure (RPKI) is to improve routing security. (See for more information.) As part of this system, a mechanism is needed to allow entities to verify that an AS has been given permission by an IP address block holder to advertise routes to one or more prefixes within that block. A ROA provides this function. The ROA makes use of the template for RPKI digitally signed objects [RFC6488], which defines a Crytopgraphic Message Syntax (CMS) wrapper for the ROA content as well as a generic validation procedure for RPKI signed objects. Therefore, to complete the specification of the ROA (see Section 4 of ), this document defines:

• The OID that identifies the signed object as being a ROA. (This OID appears within the eContentType in the encapContentInfo object as well as the content-type signed attribute in the signerInfo object).
• The ASN.1 syntax for the ROA eContent. (This is the payload that specifies the AS being authorized to originate routes as well as the prefixes to which the AS may originate routes.) The ROA eContent is ASN.1 encoded using the Distinguished Encoding Rules (DER) .
• Additional steps required to validate ROAs (in addition to the validation steps specified in ).

Changes from RFC6482 This section summarizes the significant changes between and the profile described in this document.

• Clarifications on the requirements for IP Addresses and AS Identifiers X.509 certificate extension.
• Strengthening of ASN.1 formal notation.
• Incorporate errata.
• Add an example ROA payload and ROA as appendix.

Related Work It is assumed that the reader is familiar with the terms and concepts described in "Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile" and "X.509 Extensions for IP Addresses and AS Identifiers" . Additionally, this document makes use of the RPKI signed object profile ; thus, familiarity with that document is assumed. Note that the RPKI signed object profile makes use of certificates adhering to the RPKI Resource Certificate Profile ; thus, familiarly with that profile is also assumed.

The ROA ContentType The content-type for a ROA is defined as routeOriginAuthz and has the numerical value of 1.2.840.113549.1.9.16.1.24. This OID MUST appear both within the eContentType in the encapContentInfo object as well as the ContentType signed attribute in the signerInfo object (see ).

The ROA eContent The content of a ROA identifies a single AS that has been authorized by the address space holder to originate routes and a list of one or more IP address prefixes that will be advertised. If the address space holder needs to authorize multiple ASes to advertise the same set of address prefixes, the holder issues multiple ROAs, one per AS number. A ROA is formally defined as: RPKI-ROA-2022 { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs9(9) smime(16) mod(0) id-mod-rpkiROA-2022(TBD) } DEFINITIONS EXPLICIT TAGS ::= BEGIN IMPORTS CONTENT-TYPE 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) } ; ct-routeOriginAttestation CONTENT-TYPE ::= { TYPE RouteOriginAttestation IDENTIFIED BY id-ct-routeOriginAuthz } id-ct-routeOriginAuthz OBJECT IDENTIFIER ::= { iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9) id-smime(16) id-ct(1) routeOriginAuthz(24) } RouteOriginAttestation ::= SEQUENCE { version [0] INTEGER DEFAULT 0, asID ASID, ipAddrBlocks SEQUENCE (SIZE(1..2)) OF ROAIPAddressFamily } ASID ::= INTEGER (0..4294967295) ROAIPAddressFamily ::= SEQUENCE { -- Note: addressFamily can only be '0001'H (IPv4) or '0002'H (IPv6) -- addressFamily OCTET STRING (SIZE(2)), addresses SEQUENCE (SIZE(1..MAX)) OF ROAIPAddress } ROAIPAddress ::= SEQUENCE { address IPAddress, -- Note: maxLength must be equal or larger than size of IPAddress, -- -- and equal or smaller to what the AFI context permits -- maxLength INTEGER (0..128) OPTIONAL } -- Note: if the ROAIPAddressFamily's addressFamily is IPv4, the -- -- IPAddress' size cannot exceed 32; conversely if addressFamily -- -- is IPv6, size can't exceed 128. -- IPAddress ::= BIT STRING (SIZE(0..128)) END

version The version number of the RouteOriginAttestation MUST be 0.

asID The asID field contains the AS number that is authorized to originate routes to the given IP address prefixes.

ipAddrBlocks The ipAddrBlocks field encodes the set of IP address prefixes to which the AS is authorized to originate routes. Note that the syntax here is more restrictive than that used in the IP Address Delegation extension defined in RFC 3779. That extension can represent arbitrary address ranges, whereas ROAs need to represent only prefixes. Within the ROAIPAddressFamily structure, addressFamily contains the Address Family Identifier (AFI) of an IP address family. This specification only supports IPv4 and IPv6. Therefore, addressFamily MUST be either 0001 or 0002. There MUST be only one instance of ROAIPAddressFamily per unique AFI. The ROAIPAddressFamily structure MUST NOT appear more than twice. Within a ROAIPAddress structure, the addresses field represents prefixes as a sequence of type IPAddress. (See [RFC3779] for more details). If present, the maxLength MUST be an integer greater than or equal to the length of the accompanying prefix, and less than or equal to the length (in bits) of an IP address in the address family (32 for IPv4 and 128 for IPv6). When present, the maxLength specifies the maximum length of the IP address prefix that the AS is authorized to advertise. (For example, if the IP address prefix is 203.0.113/24 and the maxLength is 26, the AS is authorized to advertise any more specific prefix with a maximum length of 26. In this example, the AS would be authorized to advertise 203.0.113/24, 203.0.113.128/25, or 203.0.113.0/25, but not 203.0.113.0/27.) When the maxLength is not present, the AS is only authorized to advertise the exact prefix specified in the ROA. Note that a valid ROA may contain an IP address prefix (within a ROAIPAddress element) that is encompassed by another IP address prefix (within a separate ROAIPAddress element). For example, a ROA may contain the prefix 203.0.113/24 with maxLength 26, as well as the prefix 203.0.113.0/28 with maxLength 28. (Such a ROA would authorize the indicated AS to advertise any prefix beginning with 203.0.113 with a minimum length of 24 and a maximum length of 26, as well as the specific prefix 203.0.113.0/28.) Additionally, a ROA MAY contain two ROAIPAddress elements, where the IP address prefix is identical in both cases. However, this is NOT RECOMMENDED as, in such a case, the ROAIPAddress with the shorter maxLength grants no additional privileges to the indicated AS and thus can be omitted without changing the meaning of the ROA.

ROA Validation Before a relying party can use a ROA to validate a routing announcement, the relying party MUST first validate the ROA. To validate a ROA, the relying party MUST perform all the validation checks specified in as well as the following additional ROA-specific validation steps.

• The IP Address Delegation extension is present in the end-entity (EE) certificate (contained within the ROA), and every IP address prefix(es) in the ROA payload is contained within the set of IP addresses specified by the EE certificate's IP Address Delegation extension.
• The EE certificate MUST NOT use "inherit" elements as described in .
• The Autonomous System Identifier Delegation Extension described in is not used in Route Origin Authorizations and MUST NOT be present.

Security Considerations There is no assumption of confidentiality for the data in a ROA; it is anticipated that ROAs will be stored in repositories that are accessible to all ISPs, and perhaps to all Internet users. There is no explicit authentication associated with a ROA, since the PKI used for ROA validation provides authorization but not authentication. Although the ROA is a signed, application-layer object, there is no intent to convey non-repudiation via a ROA. The purpose of a ROA is to convey authorization for an AS to originate a route to the prefix(es) in the ROA. Thus, the integrity of a ROA MUST be established. The ROA specification makes use of the RPKI signed object format; thus, all security considerations in also apply to ROAs. Additionally, the signed object profile uses the CMS signed message format for integrity; thus, ROAs inherit all security considerations associated with that data structure. The right of the ROA signer to authorize the target AS to originate routes to the prefix(es) is established through use of the address space and AS number PKI described in . Specifically, one MUST verify the signature on the ROA using an X.509 certificate issued under this PKI, and check that the prefix(es) in the ROA are contained within those in the certificate's IP Address Delegation Extension.

IANA Considerations

SMI Security for S/MIME CMS Content Type (1.2.840.113549.1.9.16.1) The IANA has allocated for this document in the "SMI Security for S/MIME CMS Content Type (1.2.840.113549.1.9.16.1)" registry: Upon publication of this document, IANA is requested to reference the RFC publication instead of this draft.

RPKI Signed Objects sub-registry The IANA has registered the OID for the RPKI Signed Checklist in the "RPKI Signed Objects" registry created by as follows:

File Extension The IANA has added an item for the ROA file extension to the "RPKI Repository Name Schemes" registry created by as follows: Upon publication of this document, IANA is requested to make this addition permanent and to reference the RFC publication instead of this draft.

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

Media Type The IANA is requested to update the media type application/rpki-roa in the "Media Type" registry as follows: Intended usage: COMMON Restrictions on usage: None 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 two X.509 v3 certificate extensions. The first binds a list of IP address blocks, or prefixes, to the subject of a certificate. The second binds a list of autonomous system identifiers to the subject of a certificate. These extensions may be used to convey the authorization of the subject to use the IP addresses and autonomous system identifiers contained in the extensions. [STANDARDS-TRACK] This document describes the Cryptographic Message Syntax (CMS). This syntax is used to digitally sign, digest, authenticate, or encrypt arbitrary message content. [STANDARDS-TRACK] 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 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. [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] 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. ITU-T Informative References This memo profiles the X.509 v3 certificate and X.509 v2 certificate revocation list (CRL) for use in the Internet. An overview of this approach and model is provided as an introduction. The X.509 v3 certificate format is described in detail, with additional information regarding the format and semantics of Internet name forms. Standard certificate extensions are described and two Internet-specific extensions are defined. A set of required certificate extensions is specified. The X.509 v2 CRL format is described in detail along with standard and Internet-specific extensions. An algorithm for X.509 certification path validation is described. An ASN.1 module and examples are provided in the appendices. [STANDARDS-TRACK] This document describes an architecture for an infrastructure to support improved security of Internet routing. The foundation of this architecture is a Resource Public Key Infrastructure (RPKI) that represents the allocation hierarchy of IP address space and Autonomous System (AS) numbers; and a distributed repository system for storing and disseminating the data objects that comprise the RPKI, as well as other signed objects necessary for improved routing security. As an initial application of this architecture, the document describes how a legitimate holder of IP address space can explicitly and verifiably authorize one or more ASes to originate routes to that address space. Such verifiable authorizations could be used, for example, to more securely construct BGP route filters. This document is not an Internet Standards Track specification; it is published for informational purposes. This document describes the commonly used base 64, base 32, and base 16 encoding schemes. It also discusses the use of line-feeds in encoded data, use of padding in encoded data, use of non-alphabet characters in encoded data, use of different encoding alphabets, and canonical encodings. [STANDARDS-TRACK]

Acknowledgements The authors wish to thank Charles Gardiner and Russ Housley for their help and contributions. Additionally, the authors thank Rob Austein, Roque Gagliano, Danny McPherson, and Sam Weiler for their careful reviews and helpful comments.

Example ROA eContent Payload Below an example of a DER encoded ROA eContent is provided with annotation following the '#' character. ]]> Below is a complete Base64 encoded RPKI ROA Signed Object.