Semi-Static Diffie-Hellman Key Establishment for TLS 1.3
draft-rescorla-tls-semistatic-dh-01
|
| Document |
Type |
|
Active Internet-Draft (individual)
|
|
Last updated |
|
2019-04-22
|
|
Stream |
|
(None)
|
|
Intended RFC status |
|
(None)
|
|
Formats |
|
plain text
pdf
html
bibtex
|
| Stream |
Stream state |
|
(No stream defined) |
|
Consensus Boilerplate |
|
Unknown
|
|
RFC Editor Note |
|
(None)
|
| IESG |
IESG state |
|
I-D Exists
|
|
Telechat date |
|
|
|
Responsible AD |
|
(None)
|
|
Send notices to |
|
(None)
|
TLS Working Group E. Rescorla
Internet-Draft Mozilla
Intended status: Standards Track N. Sullivan
Expires: October 24, 2019 Cloudflare
C. Wood
Apple Inc.
April 22, 2019
Semi-Static Diffie-Hellman Key Establishment for TLS 1.3
draft-rescorla-tls-semistatic-dh-01
Abstract
TLS 1.3 [I-D.ietf-tls-tls13] specifies a signed Diffie-Hellman
exchange modelled after SIGMA [SIGMA]. This design is suitable for
endpoints whose certified credential is a signing key, which is the
common situation for current TLS servers. This document describes a
mode of TLS 1.3 in which one or both endpoints have a certified DH
key which is used to authenticate the exchange.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on October 24, 2019.
Copyright Notice
Copyright (c) 2019 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
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
Rescorla, et al. Expires October 24, 2019 [Page 1]
Internet-Draft TLS 1.3 Semi-Static KX April 2019
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 are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Protocol Overview . . . . . . . . . . . . . . . . . . . . . . 3
3. Negotiation . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Certificate Format . . . . . . . . . . . . . . . . . . . . . 5
5. Cryptographic Details . . . . . . . . . . . . . . . . . . . . 5
5.1. Certificate Verify Computation . . . . . . . . . . . . . 5
5.2. Key Schedule . . . . . . . . . . . . . . . . . . . . . . 6
6. Early Data and Resumption . . . . . . . . . . . . . . . . . . 6
7. Client Authentication . . . . . . . . . . . . . . . . . . . . 6
8. Security Considerations . . . . . . . . . . . . . . . . . . . 7
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 7
10.1. Normative References . . . . . . . . . . . . . . . . . . 7
10.2. Informative References . . . . . . . . . . . . . . . . . 8
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8
1. Introduction
DISCLAIMER: This is a work-in-progress draft and has not yet seen
significant security analysis. Analysis of the modified TLS 1.3 -21
Tamarin model is currently underway. Thus, this draft should not be
used as a basis for building production systems.
TLS 1.3 [I-D.ietf-tls-tls13] specifies a signed Diffie-Hellman
exchange modeled after SIGMA [SIGMA]. This design is suitable for
endpoints whose certified credential is a signing key, which is the
common situation for current TLS servers, which is why it was
selected for TLS 1.3.
However, it is also possible - although currently rare - for
endpoints to have a credential which is an (EC)DH key. This can
happen in one of two ways:
o They may be issued a certificate with an (EC)DH key, as specified
for instance in [I-D.ietf-curdle-pkix]
o They may have a signing key which they use to generate a delegated
credential [I-D.ietf-tls-subcerts] containing an (EC)DH key.
In these situations, a signed DH exchange is not appropriate, and
instead a design in which the server authenticates via its long-term
Rescorla, et al. Expires October 24, 2019 [Page 2]
Internet-Draft TLS 1.3 Semi-Static KX April 2019
Show full document text