Internet-Draft VRP Notation October 2023
Bruijnzeels, et al. Expires 22 April 2024 [Page]
Network Working Group
Intended Status:
T. Bruijnzeels
NLnet Labs
T. de Kock
O. Borchert
D. Ma

Human Readable Validate ROA Payload Notation


This document defines a human readable notation for Validated ROA Payloads (VRP, RFC 6811) based on ABNF (RFC 5234) for use with RPKI tooling and documentation.

Status of This Memo

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Table of Contents

1. Requirements notation

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. Introduction

This informational document defines a human readable notation for Validated ROA Payloads (VRPs) [RFC6811].

We provide this notation because it can help to create consistency between RPKI Relying Party software output, making it easier for operators to compare results. It can also be used by RPKI Certificate Authorities (CA) command line interfaces and/or configuration. E.g. allowing a CA to provide a listing of intended VRPs which can be easily compared to RP output. Our final goal is that this will be helpful for documentation.

That said, this document is informational. Implementations can choose to use their own notation styles instead of, or in addition to this.

3. VRP Notation Definition

This specification uses ABNF syntax specified in [RFC5234].

notation      = vrp-prefix separator origin-asn
vrp-prefix    = v4-vrp-prefix / v6-vrp-prefix

v4-vrp-prefix = v4-cidr ["-" max-length-v4]
v4-cidr       = v4-address "/" v4-pfx-length
v4-address    = v4-byte "." v4-byte "." v4-byte "." v4-byte
v4-byte       = %d0-255
v4-pfx-length = %d0-32
v4-max-length = %d0-32

v6-vrp-prefix = v6-cidr ["-" v6-max-length]
v6-cidr       = v6-address "/" v6-pfx-length
v6-address    = (v6-un / v6-no-0 / v6-l-0 / v6-m-0 / v6-t-0)
v6-un         = "::"
v6-no-0       = v6-bytes 7*7(":" v6-bytes)
v6-l-0        = ":" 1*7(":" v6-bytes)
v6-m-0        = 1*6(v6-bytes ":") ":" 1*6(":" v6-bytes)
v6-t-0        = 1*7(v6-bytes ":") ":"
v6-bytes      = %x0-FFFF
v6-pfx-length = %d0-128
v6-max-length = %d0-128

separator     = " => "

origin-asn    = ["AS"] uint32
uint32        = %d0-4294967295

3.1. roa-prefix

This field denotes a single Validated ROA Prefix (VRP) as defined in section 2 of [RFC6811]. VRPs consist of either an IPv4 or an IPv6 prefix using CIDR prefix notation, optionally followed by a max-length value.

Unfortunately we could not find pre-existing formal ABNF syntax specifications for IPv4 and IPv6 CIDR prefix notation. The fairly basic specifications defined above cover the notation of valid CIDR prefixes, but it should be noted that they also allow for the notation of invalid IPv6 addresses, and allow for prefix length values that are not applicable to the base IP address. Rather than trying to define these rules in detail here we refer to section 3.1 of [RFC4632] for guidelines on IPv4 CIDR notation and section 2.3 of [RFC4291] for IPv6.

If the max-length is specified then its value needs to be the same as or longer than the length of the prefix within the bounds applicable to the address family of the prefix. If it is omitted then the effective max-length for the VRP will be the same as the VPR prefix length.

3.2. origin-asn

This field can optionally be prepended with the string "AS" followed by a decimal value of a 32-bit Autonomous System Number using the asplain presentation as specified in [RFC5396]. Decimal values MUST be used, and values MUST be part of the range 0-4294967295.

4. Example Notations => AS65000 => AS65000 => AS65000 => AS65000

2001:db8::/32 => 65000,
2001:db8::/32-32 => 65000,
2001:db8::/32-128 => 65000,
2001:db8::/128 => 65000,

5. IANA Considerations

This document has no IANA actions.

6. Security Considerations


7. Acknowledgements

Thanks to Nan Geng for the editorial feedback.

8. Normative References

Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, , <>.
Hinden, R. and S. Deering, "IP Version 6 Addressing Architecture", RFC 4291, DOI 10.17487/RFC4291, , <>.
Fuller, V. and T. Li, "Classless Inter-domain Routing (CIDR): The Internet Address Assignment and Aggregation Plan", BCP 122, RFC 4632, DOI 10.17487/RFC4632, , <>.
Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, DOI 10.17487/RFC5234, , <>.
Huston, G. and G. Michaelson, "Textual Representation of Autonomous System (AS) Numbers", RFC 5396, DOI 10.17487/RFC5396, , <>.
Mohapatra, P., Scudder, J., Ward, D., Bush, R., and R. Austein, "BGP Prefix Origin Validation", RFC 6811, DOI 10.17487/RFC6811, , <>.
Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, , <>.

Authors' Addresses

Tim Bruijnzeels
NLnet Labs
Ties de Kock
Oliver Borchert
Di Ma