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
[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.
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].
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.
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]
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]
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]
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]
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.
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.
[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/>.