RFC 5807
Definition of Master Key between PANA Client and Enforcement Point
RFC 5807 🎀 Definition of Master Key between PANA Client and Enforcement Point
Okay bestie, let's start with the ID card 🪪✨ This is RFC 5807, from the Internet Engineering Task Force (IETF), and it's titled "Definition of Master Key between PANA Client and Enforcement Point". Y. Ohba from Toshiba and A. Yegin from Samsung wrote it. It's a Standards Track document, dated March 2010, with ISSN 2070-1721. The header doesn't list anything it obsoletes or updates, so it stands on its own 💅
Abstract ✨
Okay so this doc defines a master key 🔑 that gets used between a client of the Protocol for carrying Authentication for Network Access (PANA) and an enforcement point. Its whole job is bootstrapping lower-layer ciphering. The key is derived from the Master Session Key of the Extensible Authentication Protocol, and that only happens after PANA authentication succeeds. The big payoff is that it guarantees cryptographic independence among enforcement points that get bootstrapped from PANA authentication across different address families. Iconic, honestly 👑
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 5741.
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc5807.
Copyright Notice ©️
Copyright (c) 2010 IETF Trust and the persons identified as the document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, since they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions, and they are provided without warranty as described in the Simplified BSD License.
Table of Contents 🗂️
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Specification of Requirements . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. PaC-EP Master Key . . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Key Name of PEMK . . . . . . . . . . . . . . . . . . . . . 5
3.2. Scope of PEMK . . . . . . . . . . . . . . . . . . . . . . . 5
3.3. Context of PEMK . . . . . . . . . . . . . . . . . . . . . . 5
3.4. Lifetime of PEMK . . . . . . . . . . . . . . . . . . . . . 5
4. Security Considerations . . . . . . . . . . . . . . . . . . . . 5
4.1. Channel Binding . . . . . . . . . . . . . . . . . . . . . . 5
4.2. Guideline for Distributing PEMK from PAA to EP . . . . . . 6
5. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . 6
6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6.1. Normative References . . . . . . . . . . . . . . . . . . . 6
6.2. Informative References . . . . . . . . . . . . . . . . . . 71. Introduction ✨
Okay so PANA [RFC5191] is designed to make network access authentication and authorization for clients in access networks easier. It carries Extensible Authentication Protocol (EAP) [RFC3748] between a PANA Client (PaC) and a PANA Authentication Agent (PAA). The PAA acts as an authentication gateway to the Authentication Server (AS). The PANA framework [RFC5193] introduces another entity called an Enforcement Point (EP). The EP lives in the access network and lets authorized PaCs' data traffic through while blocking everyone else, depending on the PANA authentication and authorization result (Figure 1). The EP and PAA can be implemented on the same device or on separate devices 🦋
RADIUS,
Diameter,
+-----+ PANA +-----+ LDAP, API, etc. +-----+
| PaC |<----------------->| PAA |<------------------->| AS |
+-----+ +-----+ +-----+
^ ^
| |
| +-----+ |
IKE, +-------->| EP |<--------+ ANCP, API, etc.
4-way handshake, +-----+
etc. .
.
.
v
Data traffic
Figure 1: PANA Functional ModelThe EP uses non-cryptographic or cryptographic filters to selectively allow and discard data packets. These filters may be applied at the link-layer or the IP-layer [PANA-IPSEC]. When cryptographic access control is used, a secure association protocol [RFC3748] needs to run between the PaC and EP. After that protocol completes, link- or network-layer per-packet security (for example, IPsec ESP) gets enabled for integrity protection, data origin authentication, replay protection, and optionally confidentiality protection 🔐
This document defines the PaC-EP Master Key (PEMK). A secure association protocol uses it as the pre-shared secret between the PaC and EP, so the cryptographic filters in the access network can switch on. The PEMK is defined to guarantee cryptographic independence among EPs bootstrapped from PANA authentication across different address families. This document also describes a guideline for distributing PEMKs from the PAA to EP 🌸
Heads up: this doc does not specify a way for a PaC to figure out whether the lower layer needs a secure association protocol, or whether the pre-shared secret for that protocol has to be bootstrapped from PANA authentication. Each lower-layer protocol may define that mechanism itself.
1.1. Specification of Requirements 📏
Several words are used in this document to signify the requirements of the specification. They're often capitalized. The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119] 💜
2. Terminology 🧚
This document reuses the following terms defined in [RFC5191]: PaC (PANA Client), PAA (PANA Authentication Agent), EP (Enforcement Point), MSK (Master Session Key), PANA Session, and Session Identifier.
3. PaC-EP Master Key 🔑
A PEMK (PaC-EP Master Key) is derived from an available MSK. The PEMK is 64 octets long and gets calculated like this:
PEMK = prf+(MSK, "IETF PEMK" | SID | KID | EPID)Here, | denotes concatenation.
- The prf+ function is defined in IKEv2 [RFC4306]. The pseudo-random function used for prf+ is specified in the PRF-Algorithm AVP carried in a PANA-Auth-Request message with the 'S' (Start) bit set.
- "IETF PEMK" is the ASCII code representation of the non-NULL terminated string (not counting the double quotes around it).
- SID is a four-octet Session Identifier [RFC5191].
- KID is the content of the Key-ID AVP [RFC5191] associated with the MSK.
- EPID is the identifier of the EP. The first two octets represent the AddressType, which contains an Address Family defined in [IANAADFAM]. The remaining octets encode the address value, and its length is determined by the AddressType. The AddressType is used to tell apart the content and format of the remaining octets for the address value. Using the combination of address family and address value guarantees the cryptographic independence of PEMKs among multiple EPs bootstrapped from PANA authentication across multiple address families. How a PaC discovers an EPID is out of scope for this document.
3.1. Key Name of PEMK 🏷️
The key name of the PEMK is defined as follows.
PEMKname = SHA1(EPID | SID | KID)Here, SHA1 denotes the SHA-1 algorithm specified in [SHS]. Including the EPID, SID, and KID gives uniqueness to PEMK names among multiple PaC-EP pairs under a given PAA ✨
3.2. Scope of PEMK 🎯
One PEMK is used between one PaC and one EP. A PEMK MUST NOT be shared among multiple PaCs or EPs.
3.3. Context of PEMK 🫧
A PEMK is used as the pre-shared key of the secure association protocol within the scope of the PEMK. A PEMK MUST NOT be used for any other usage.
3.4. Lifetime of PEMK ⏳
The lifetime of a PEMK MUST be less than or equal to the lifetime of the MSK it's derived from. At the end of the lifetime, the PEMK and its associated states MUST be deleted.
to be continued 🧚 part 2 covers Security Considerations, Acknowledgments, and References, and it's the spicy part, so stay tuned 🔥
6.2. Informative References 📚✨
okay so this is the bonus reading list, bestie 🧚 here are the four refs the doc points to, with every detail intact 💅
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC4962] Housley, R. and B. Aboba, "Guidance for Authentication,
Authorization, and Accounting (AAA) Key Management",
BCP 132, RFC 4962, July 2007.
[RFC5193] Jayaraman, P., Lopez, R., Ohba, Y., Parthasarathy, M.,
and A. Yegin, "Protocol for Carrying Authentication for
Network Access (PANA) Framework", RFC 5193, May 2008.
[PANA-IPSEC] Parthasarathy, M., "PANA Enabling IPsec based Access
Control", Work in Progress, July 2005.Okay the [RFC2119] one is the iconic one that defines the key words, so it's giving foundation 🫶 [RFC4962] is all about AAA key management guidance 🔐 and [RFC5193] is the PANA framework, which is literally the whole PANA world 🌸 and [PANA-IPSEC] is a work in progress from July 2005 that's about PANA enabling IPsec based access control 🦋
Authors' Addresses 💌
here's who wrote it, bestie, with the contact deets 💖
Yoshihiro Ohba
Toshiba Corporate Research and Development Center
1 Komukai-Toshiba-cho
Saiwai-ku, Kawasaki, Kanagawa 212-8582
Japan
Phone: +81 44 549 2230
EMail: yoshihiro.ohba@toshiba.co.jp
Alper Yegin
Samsung
Istanbul
Turkey
EMail: alper.yegin@yegin.orgYoshihiro is at Toshiba's R&D center in Kawasaki, and Alper is at Samsung in Istanbul 🌈 both of them are literal legends of the PANA world ✨
📦 where this page comes from
- ietf: rfc5807 2010-03
- 💖 girlified by claude-haiku-5-5 on : a language model's rewrite of the original, under its terms