eap Mailing List: Proposed Resolution to Issue 185: Key Framework Review

[Bernard Aboba (aboba]

The text of Issue 185 is enclosed below.  The proposed fix is as follows:

In Section 1.2, change:

" AAA-Key
A key derived by the EAP peer and EAP server and transported to
the authenticator. In 802.11 terminology, the first 32 octets of
the AAA-Key is known as the Pairwise Master Key (PMK)."

To:

" AAA-Key
A key derived by the EAP peer and EAP server and transported to
the authenticator. In IEEE 802.11 terminology, the first 32 octets of
the AAA-Key is known as the Pairwise Master Key (PMK)."

In Section 1.3.3, change:

"[2] Generation of fresh transient session keys. This is typically"

To:

"[2] Generation of fresh transient session keys (TSKs). This is
typically"

In Section 1.4 change:

Within EAP, "fast handoff" is defined as a conversation in which the
EAP exchange (phase 1a) and associated AAA passthrough is bypassed,
so as to reduce latency. Depending on the fast handoff mechanism,
AAA-Key transport (phase 1b) may also be bypassed in favor a context
transfer (see [IEEE80211f] and [I-D.aboba-802-context]) or it may be
provided in a pre-emptive manner as in [IEEE-03-084] and
[I-D.irtf-aaaarch-handoff]."

To:

"Within EAP, "fast handoff" is defined as a conversation in which the
EAP exchange (phase 1a) and associated AAA passthrough is bypassed,
so as to reduce latency. Depending on the fast handoff mechanism,
AAA-Key transport (phase 1b) may also be bypassed or it may be
provided in a pre-emptive manner as in [IEEE-03-084] and
[I-D.irtf-aaaarch-handoff]."

In Section 1.4.1, change:

"Similarly, in a network where access is restricted based on the day
and time, SSID, Calling-Station-Id or other factors, unless the"

To:

"Similarly, in a network where access is restricted based on the day
and time, Service Set Identifier (SSID), Calling-Station-Id or
other factors, unless the"

In Section 2.2 change:

"Master Session Key (MSK)
Keying material (at least 64 octets) that is derived between the
EAP client and server and exported by the EAP method."

To:

"Master Session Key (MSK)
Keying material that is derived between the EAP peer and
server and exported by the EAP method. The MSK is at least
64 octets in length. In existing implementations a AAA
server acting as an EAP server transports the MSK to the
authenticator.

Extended Master Session Key (EMSK)
Additional keying material derived between the EAP client
and server that is exported by the EAP method. The EMSK is
at least 64 octets in length. The EMSK is reserved for
future uses that are not defined yet and is not provided to
a third party."

Delete the existing definition of the EMSK.

Change:

"Initialization Vector (IV)
A quantity of at least 64 octets, suitable for use in an
initialization vector field, that is derived between the EAP
client and server. Since the IV is a known value in methods such
as EAP-TLS [RFC2716], it cannot be used by itself for computation
of any quantity that needs to remain secret. As a result, its use
has been deprecated and EAP methods are not required to generate
it."

To:

"Initialization Vector (IV)
A quantity of at least 64 octets, suitable for use in an
initialization vector field, that is derived between the EAP
client and server. Since the IV is a known value in methods such
as EAP-TLS [RFC2716], it cannot be used by itself for computation
of any quantity that needs to remain secret. As a result, its use
has been deprecated and EAP methods are not required to generate
it. However, when it is generated it MUST be unpredictable."

In Section 2.3, Figure 3, delete ", TEK Deriv." from the figure.

-------------------------------------------------------
Issue 185: Key Framework Review
Submitter name: Russ Housley
Submitter email address: housley [at] vigilsec.com
Date first submitted: October 15, 2003
Reference:
http://www.drizzle.com/~aboba/EAP/draft-ietf-eap-keying-00-comment.txt
Document: Keying Framework-00
Comment type: T
Priority: S
Section: Various
Rationale/Explanation of issue:

Here is my review of the Key Framework document:

http://www.drizzle.com/~aboba/EAP/draft-ietf-eap-keying-00-comment.txt