Specification for the Derivation of Root Keys from an Extended Master Session Key (EMSK)

Abstract

Status of This Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.

Diameter Attribute-Value Pairs for Cryptographic Key Transport

“…However, recent work (see, for example, [RFC5295]) has specified methods to derive other keys from the keying material created during EAP method execution that may require transport in addition to the Master Session Key (MSK). Also, the EAP Re-authentication Protocol (ERP) [RFC6696] specifies new keys that may need to be transported between Diameter nodes.…”

Diameter IKEv2 SK: Using Shared Keys to Support Interaction between IKEv2 Servers and Diameter Servers

“…When the default SK-generation procedure specified in this document is used, the peer side that provides the SK to the IKEv2 peer, as well as the Diameter server, SHALL use the same SK derivation that follows the methodology similar to that specified in Section 3.1 of [RFC5295], specifically: SK = KDF(PSK, key label | "\0" | Ni | Nr | IDi | length)…”

Distribution of EAP-Based Keys for Handover and Re-Authentication

“…By definition, any key-generating EAP method derives a Master Session Key (MSK) and an Extended Master Session Key (EMSK). [RFC5295] reserves the EMSK for the sole purpose of deriving root keys that can be used for specific purposes called usages. In particular, [RFC5295] defines how to create a usagespecific root key (USRK) for bootstrapping security in a specific application, a domain-specific root key (DSRK) for bootstrapping security of a set of services within a domain, and a usage-specific DSRK (DSUSRK) for a specific application within a domain.…”

“…[RFC5295] reserves the EMSK for the sole purpose of deriving root keys that can be used for specific purposes called usages. In particular, [RFC5295] defines how to create a usagespecific root key (USRK) for bootstrapping security in a specific application, a domain-specific root key (DSRK) for bootstrapping security of a set of services within a domain, and a usage-specific DSRK (DSUSRK) for a specific application within a domain. [RFC5296] defines a re-authentication root key (rRK) that is a USRK designated for re-authentication.…”