X.509v3 Transport Layer Security (TLS) Feature Extension
RFC 7633
| Document | Type |
RFC - Proposed Standard
(October 2015; Errata)
Was draft-hallambaker-tlsfeature (individual in sec area)
|
|
|---|---|---|---|
| Last updated | 2015-12-28 | ||
| Stream | IETF | ||
| Formats | plain text html pdf htmlized bibtex | ||
| Reviews | |||
| Stream | WG state | Submitted to IESG for Publication | |
| Document shepherd | Sean Turner | ||
| Shepherd write-up | Show (last changed 2015-03-09) | ||
| IESG | IESG state | RFC 7633 (Proposed Standard) | |
| Consensus Boilerplate | Yes | ||
| Telechat date | |||
| Responsible AD | Stephen Farrell | ||
| Send notices to | (None) | ||
| IANA | IANA review state | Version Changed - Review Needed | |
| IANA action state | RFC-Ed-Ack | ||
Internet Engineering Task Force (IETF) P. Hallam-Baker
Request for Comments: 7633 Comodo Group Inc.
Category: Standards Track October 2015
ISSN: 2070-1721
X.509v3 Transport Layer Security (TLS) Feature Extension
Abstract
The purpose of the TLS feature extension is to prevent downgrade
attacks that are not otherwise prevented by the TLS protocol. In
particular, the TLS feature extension may be used to mandate support
for revocation checking features in the TLS protocol such as Online
Certificate Status Protocol (OCSP) stapling. Informing clients that
an OCSP status response will always be stapled permits an immediate
failure in the case that the response is not stapled. This in turn
prevents a denial-of-service attack that might otherwise be possible.
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/rfc7633.
Copyright Notice
Copyright (c) 2015 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, as 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 are provided without warranty as
described in the Simplified BSD License.
Hallam-Baker Standards Track [Page 1]
RFC 7633 TLS Feature Extension October 2015
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.1. Requirements Language . . . . . . . . . . . . . . . . . . 2
2.2. TLS Feature, X.509 Extension . . . . . . . . . . . . . . 3
3. Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Syntax . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.1. TLS Feature . . . . . . . . . . . . . . . . . . . . . . . 4
4.2. Use . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4.2.1. Certificate Signing Request . . . . . . . . . . . . . 5
4.2.2. Certificate Signing Certificate . . . . . . . . . . . 5
4.2.3. End-Entity Certificate . . . . . . . . . . . . . . . 5
4.3. Processing . . . . . . . . . . . . . . . . . . . . . . . 6
4.3.1. Certification Authority . . . . . . . . . . . . . . . 6
4.3.2. Server . . . . . . . . . . . . . . . . . . . . . . . 7
4.3.3. Client . . . . . . . . . . . . . . . . . . . . . . . 7
5. Security Considerations . . . . . . . . . . . . . . . . . . . 7
5.1. Alternative Certificates and Certificate Issuers . . . . 7
5.2. Denial of Service . . . . . . . . . . . . . . . . . . . . 8
5.3. Cipher Suite Downgrade Attack . . . . . . . . . . . . . . 8
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
7. Normative References . . . . . . . . . . . . . . . . . . . . 9
Appendix A. ASN.1 Module . . . . . . . . . . . . . . . . . . . . 10
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 11
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 11
1. Introduction
The Transport Layer Security (TLS) feature extension provides a means
of preventing downgrade attacks that are not otherwise prevented by
the TLS protocol.
Since the TLS protocol itself provides strong protection against most
forms of downgrade attack including downgrade attacks against cipher
suite choices offered and client credentials, the TLS feature
extension is only relevant to the validation of TLS protocol
credentials.
2. Definitions
2.1. Requirements Language
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 RFC 2119 [RFC2119].
Hallam-Baker Standards Track [Page 2]
RFC 7633 TLS Feature Extension October 2015
2.2. TLS Feature, X.509 Extension
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