Internet Engineering Task Force (IETF) L. Law
Request for Comments: 6379 J. Solinas
Obsoletes: 4869 NSA
Category: Informational October 2011
ISSN: 2070-1721
Suite B Cryptographic Suites for IPsec
Abstract
This document proposes four cryptographic user interface suites
("UI suites") for IP Security (IPsec), similar to the two suites
specified in RFC 4308. The four new suites provide compatibility
with the United States National Security Agency's Suite B
specifications. This document obsoletes RFC 4869, which presented
earlier versions of these suites.
Status of This Memo
This document is not an Internet Standards Track specification; it is
published for informational purposes.
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). Not all documents
approved by the IESG are a candidate for any level of Internet
Standard; see 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/rfc6379.
Copyright Notice
Copyright (c) 2011 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.
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RFC 6379 Suite B Crypto for IPsec October 2011
Table of Contents
1. Introduction ....................................................2
2. Requirements Terminology ........................................2
3. New UI Suites ...................................................2
3.1. Suite "Suite-B-GCM-128" ....................................3
3.2. Suite "Suite-B-GCM-256" ....................................3
3.3. Suite "Suite-B-GMAC-128" ...................................4
3.4. Suite "Suite-B-GMAC-256" ...................................4
4. Security Considerations .........................................4
5. IANA Considerations .............................................5
6. Changes from RFC 4869 ...........................................5
7. References ......................................................5
7.1. Normative References .......................................5
7.2. Informative References .....................................6
1. Introduction
[RFC4308] proposes two optional cryptographic user interface suites
("UI suites") for IPsec. The two suites, VPN-A and VPN-B, represent
commonly used present day corporate VPN security choices and
anticipated future choices, respectively. [RFC4869] proposed four
new UI suites based on implementations of the United States National
Security Agency's Suite B algorithms (see [SuiteB]).
As with the VPN suites, the Suite B suites are simply collections of
values for some options in IPsec. Use of UI suites does not change
the IPsec protocols in any way.
This document reduces the scope of the suites in [RFC4869] while
retaining the original suite names. A detailed list of the changes
is given in Section 6. This document obsoletes RFC 4869.
2. Requirements Terminology
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].
3. New UI Suites
Each of the following UI suites provides choices for ESP (see
[RFC4303]) and for Internet Key Exchange (IKEv2) (see [RFC5996]).
The four suites are differentiated by the choice of cryptographic
algorithm strengths, and a choice of whether the Encapsulating
Security Payload (ESP) is to provide both confidentiality and
integrity or integrity only. The suite names are based on the
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RFC 6379 Suite B Crypto for IPsec October 2011
Advanced Encryption Standard [AES] mode and AES key length specified
for ESP.
IPsec implementations that use these UI suites MUST use the suite
names listed here. IPsec implementations SHOULD NOT use names
different than those listed here for the suites that are described,
and MUST NOT use the names listed here for suites that do not match
these values. These requirements are necessary for interoperability.
3.1. Suite "Suite-B-GCM-128"
This suite provides ESP integrity protection and confidentiality
using 128-bit AES-GCM (see [RFC4106]). This suite or the following
suite should be used when ESP integrity protection and encryption are
both needed.
ESP:
Encryption AES with 128-bit keys and 16-octet Integrity
Check Value (ICV) in GCM mode [RFC4106]
Integrity NULL
IKEv2:
Encryption AES with 128-bit keys in CBC mode
[RFC3602]
Pseudo-random function HMAC-SHA-256 [RFC4868]
Integrity HMAC-SHA-256-128 [RFC4868]
Diffie-Hellman group 256-bit random ECP group [RFC5903]
3.2. Suite "Suite-B-GCM-256"
This suite provides ESP integrity protection and confidentiality
using 256-bit AES-GCM (see [RFC4106]). This suite or the preceding
suite should be used when ESP integrity protection and encryption are
both needed.
ESP:
Encryption AES with 256-bit keys and 16-octet ICV in GCM mode
[RFC4106]
Integrity NULL
IKEv2:
Encryption AES with 256-bit keys in CBC mode
[RFC3602]
Pseudo-random function HMAC-SHA-384 [RFC4868]
Integrity HMAC-SHA-384-192 [RFC4868]
Diffie-Hellman group 384-bit random ECP group [RFC5903]
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RFC 6379 Suite B Crypto for IPsec October 2011
3.3. Suite "Suite-B-GMAC-128"
This suite provides ESP integrity protection using 128-bit AES-GMAC
(see [RFC4543]) but does not provide confidentiality. This suite or
the following suite should be used only when there is no need for ESP
encryption.
ESP:
Encryption NULL
Integrity AES with 128-bit keys in GMAC mode [RFC4543]
IKEv2:
Encryption AES with 128-bit keys in CBC mode
[RFC3602]
Pseudo-random function HMAC-SHA-256 [RFC4868]
Integrity HMAC-SHA-256-128 [RFC4868]
Diffie-Hellman group 256-bit random ECP group [RFC5903]
3.4. Suite "Suite-B-GMAC-256"
This suite provides ESP integrity protection using 256-bit AES-GMAC
(see [RFC4543]) but does not provide confidentiality. This suite or
the preceding suite should be used only when there is no need for ESP
encryption.
ESP:
Encryption NULL
Integrity AES with 256-bit keys in GMAC mode [RFC4543]
IKEv2:
Encryption AES with 256-bit keys in CBC mode
[RFC3602]
Pseudo-random function HMAC-SHA-384 [RFC4868]
Integrity HMAC-SHA-384-192 [RFC4868]
Diffie-Hellman group 384-bit random ECP group [RFC5903]
4. Security Considerations
This document inherits all of the security considerations of the
IPsec and IKEv2 documents.
Some of the security options specified in these suites may be found
in the future to have properties significantly weaker than those that
were believed at the time this document was produced.
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5. IANA Considerations
IANA maintains a registry called "Cryptographic Suites for IKEv1,
IKEv2, and IPsec" (see [IANA-Suites]). The registry consists of a
text string and an RFC number that lists the associated transforms.
The four suites in this document have been listed with this document
as the RFC reference. These entries will be updated upon approval of
this document.
The updated values for the registry are:
Identifier Defined in
Suite-B-GCM-128 RFC 6379
Suite-B-GCM-256 RFC 6379
Suite-B-GMAC-128 RFC 6379
Suite-B-GMAC-256 RFC 6379
6. Changes from RFC 4869
The changes from [RFC4869] are:
1. Removed definitions of the suites for IKEv1.
2. Removed IKE authentication methods from the suite definitions.
These now appear in [RFC6380].
3. Removed the requirements on rekeying in IKEv2.
7. References
7.1. Normative References
[IANA-Suites] Internet Assigned Numbers Authority, "Cryptographic
Suites for IKEv1, IKEv2, and IPsec",
<http://www.iana.org/assignments/crypto-suites>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3602] Frankel, S., Glenn, R., and S. Kelly, "The AES-CBC
Cipher Algorithm and Its Use with IPsec", RFC 3602,
September 2003.
[RFC4106] Viega, J. and D. McGrew, "The Use of Galois/Counter
Mode (GCM) in IPsec Encapsulating Security Payload
(ESP)", RFC 4106, June 2005.
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RFC 6379 Suite B Crypto for IPsec October 2011
[RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)",
RFC 4303, December 2005.
[RFC4308] Hoffman, P., "Cryptographic Suites for IPsec", RFC
4308, December 2005.
[RFC4543] McGrew, D. and J. Viega, "The Use of Galois Message
Authentication Code (GMAC) in IPsec ESP and AH", RFC
4543, May 2006.
[RFC4868] Kelly, S. and S. Frankel, "Using HMAC-SHA-256, HMAC-
SHA-384, and HMAC-SHA-512 with IPsec", RFC 4868, May
2007.
[RFC4869] Law, L. and J. Solinas, "Suite B Cryptographic Suites
for IPsec", RFC 4869, May 2007.
[RFC5903] Fu, D. and J. Solinas, "Elliptic Curve Groups modulo a
Prime (ECP Groups) for IKE and IKEv2", RFC 5903, June
2010.
[RFC5996] Kaufman, C., Hoffman, P., Nir, Y., and P. Eronen,
"Internet Key Exchange Protocol Version 2 (IKEv2)", RFC
5996, September 2010.
7.2. Informative References
[AES] U.S. Department of Commerce/National Institute of
Standards and Technology, "Advanced Encryption Standard
(AES)", FIPS PUB 197, November 2001,
<http://csrc.nist.gov/publications/fips/index.html>.
[RFC6380] Burgin, K. and M. Peck, "Suite B Profile for Internet
Protocol Security (IPsec)", RFC 6380, October 2011.
[SuiteB] U.S. National Security Agency, "NSA Suite B
Cryptography", January 2009, <http://www.nsa.gov/
ia/programs/suiteb_cryptography/>.
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Authors' Addresses
Laurie E. Law
National Security Agency
EMail: lelaw@orion.ncsc.mil
Jerome A. Solinas
National Security Agency
EMail: jasolin@orion.ncsc.mil
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