Difference between revisions of "RFC6160"
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received public review and has been approved for publication by the | received public review and has been approved for publication by the | ||
Internet Engineering Steering Group (IESG). Further information on | Internet Engineering Steering Group (IESG). Further information on | ||
− | Internet Standards is available in Section 2 of RFC 5741. | + | Internet Standards is available in Section 2 of [[RFC5741|RFC 5741]]. |
Information about the current status of this document, any errata, | Information about the current status of this document, any errata, | ||
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document authors. All rights reserved. | document authors. All rights reserved. | ||
− | This document is subject to BCP 78 and the IETF Trust's Legal | + | This document is subject to [[BCP78|BCP 78]] and the IETF Trust's Legal |
Provisions Relating to IETF Documents | Provisions Relating to IETF Documents | ||
(http://trustee.ietf.org/license-info) in effect on the date of | (http://trustee.ietf.org/license-info) in effect on the date of | ||
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This document describes the conventions for using several | This document describes the conventions for using several | ||
cryptographic algorithms with the Cryptographic Message Syntax (CMS) | cryptographic algorithms with the Cryptographic Message Syntax (CMS) | ||
− | + | [[RFC5652]] to protect the symmetric key package content type defined | |
− | in | + | in [[RFC6031]]. Specifically, it includes conventions necessary to |
− | implement the following CMS content types: SignedData | + | implement the following CMS content types: SignedData [[RFC5652]], |
− | EnvelopedData | + | EnvelopedData [[RFC5652]], EncryptedData [[RFC5652]], and |
− | AuthEnvelopedData | + | AuthEnvelopedData [[RFC5083]]. Familiarity with [[RFC5083]], [[RFC5652]], |
− | + | [[RFC5753]], and [[RFC6031]] is assumed. | |
This document does not define any new algorithms; instead, it refers | This document does not define any new algorithms; instead, it refers | ||
Line 62: | Line 62: | ||
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", | The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", | ||
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this | "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this | ||
− | document are to be interpreted as described in | + | document are to be interpreted as described in [[RFC2119]]. |
== SignedData == | == SignedData == | ||
If an implementation supports SignedData, then it MUST support the | If an implementation supports SignedData, then it MUST support the | ||
− | signature scheme RSA | + | signature scheme RSA [[RFC3370]] and SHOULD support the signature |
− | schemes RSA Probabilistic Signature Scheme (RSASSA-PSS) | + | schemes RSA Probabilistic Signature Scheme (RSASSA-PSS) [[RFC4056]] and |
− | Digital Signature Algorithm (DSA) | + | Digital Signature Algorithm (DSA) [[RFC3370]]. Additionally, |
− | implementations MUST support the hash function SHA-256 | + | implementations MUST support the hash function SHA-256 [[RFC5754]] in |
concert with these signature schemes, and they SHOULD support the | concert with these signature schemes, and they SHOULD support the | ||
− | hash function SHA-1 | + | hash function SHA-1 [[RFC3370]]. If an implementation supports |
SignedData, then it MAY support Elliptic Curve Digital Signature | SignedData, then it MAY support Elliptic Curve Digital Signature | ||
− | Algorithm (ECDSA) | + | Algorithm (ECDSA) [[RFC6090]][[RFC5753]]. |
== EnvelopedData == | == EnvelopedData == | ||
Line 81: | Line 81: | ||
key transport, and it MAY implement key agreement. | key transport, and it MAY implement key agreement. | ||
− | When key transport is used, RSA encryption | + | When key transport is used, RSA encryption [[RFC3370]] MUST be |
supported, and RSA Encryption Scheme - Optimal Asymmetric Encryption | supported, and RSA Encryption Scheme - Optimal Asymmetric Encryption | ||
− | Padding (RSAES-OAEP) | + | Padding (RSAES-OAEP) [[RFC3560]] SHOULD be supported. |
When key agreement is used, Diffie-Hellman (DH) ephemeral-static | When key agreement is used, Diffie-Hellman (DH) ephemeral-static | ||
− | + | [[RFC3370]] MUST be supported. When key agreement is used, Elliptic | |
− | Curve Diffie-Hellman (ECDH) | + | Curve Diffie-Hellman (ECDH) [[RFC6090]][[RFC5753]] MAY be supported. |
Regardless of the key management technique choice, implementations | Regardless of the key management technique choice, implementations | ||
− | MUST support AES-128 Key Wrap with Padding | + | MUST support AES-128 Key Wrap with Padding [[RFC5649]] as the content- |
encryption algorithm. Implementations SHOULD support AES-256 Key | encryption algorithm. Implementations SHOULD support AES-256 Key | ||
− | Wrap with Padding | + | Wrap with Padding [[RFC5649]] as the content-encryption algorithm. |
When key agreement is used, the same key-wrap algorithm MUST be used | When key agreement is used, the same key-wrap algorithm MUST be used | ||
for both key and content encryption. If the content-encryption | for both key and content encryption. If the content-encryption | ||
algorithm is AES-128 Key Wrap with Padding, then the key-wrap | algorithm is AES-128 Key Wrap with Padding, then the key-wrap | ||
− | algorithm MUST be AES-128 Key Wrap with Padding | + | algorithm MUST be AES-128 Key Wrap with Padding [[RFC5649]]. If the |
content-encryption algorithm is AES-256 Key Wrap with Padding, then | content-encryption algorithm is AES-256 Key Wrap with Padding, then | ||
the key-wrap algorithm MUST be AES-256 Key Wrap with Padding | the key-wrap algorithm MUST be AES-256 Key Wrap with Padding | ||
− | + | [[RFC5649]]. | |
== EncryptedData == | == EncryptedData == | ||
If an implementation supports EncryptedData, then it MUST implement | If an implementation supports EncryptedData, then it MUST implement | ||
− | AES-128 Key Wrap with Padding | + | AES-128 Key Wrap with Padding [[RFC5649]] and SHOULD implement AES-256 |
− | Key Wrap with Padding | + | Key Wrap with Padding [[RFC5649]]. |
NOTE: EncryptedData requires that keys be managed by other means; | NOTE: EncryptedData requires that keys be managed by other means; | ||
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If an implementation supports AuthEnvelopedData, then it MUST | If an implementation supports AuthEnvelopedData, then it MUST | ||
implement the EnvelopedData recommendations except for the content- | implement the EnvelopedData recommendations except for the content- | ||
− | encryption algorithm, which, in this case, MUST be AES-GCM | + | encryption algorithm, which, in this case, MUST be AES-GCM [[RFC5084]]; |
the 128-bit version MUST be implemented, and the 256-bit version | the 128-bit version MUST be implemented, and the 256-bit version | ||
SHOULD be implemented. Implementations MAY also support AES-CCM | SHOULD be implemented. Implementations MAY also support AES-CCM | ||
− | + | [[RFC5084]]. | |
== Public Key Sizes == | == Public Key Sizes == | ||
The easiest way to implement SignedData, EnvelopedData, and | The easiest way to implement SignedData, EnvelopedData, and | ||
− | AuthEnvelopedData is with public key certificates | + | AuthEnvelopedData is with public key certificates [[RFC5280]]. If an |
implementation supports RSA, RSASSA-PSS, DSA, RSAES-OAEP, or Diffie- | implementation supports RSA, RSASSA-PSS, DSA, RSAES-OAEP, or Diffie- | ||
Hellman, then it MUST support key lengths from 1024-bit to 2048-bit, | Hellman, then it MUST support key lengths from 1024-bit to 2048-bit, | ||
Line 132: | Line 132: | ||
== Security Considerations == | == Security Considerations == | ||
− | The security considerations from | + | The security considerations from [[RFC3370]], [[RFC3560]], [[RFC4056]], |
− | + | [[RFC5083]], [[RFC5084]], [[RFC5649]], [[RFC5652]], [[RFC5753]], [[RFC5754]], and | |
− | + | [[RFC6031]] apply. | |
The choice of content-encryption algorithms for this document was | The choice of content-encryption algorithms for this document was | ||
− | based on | + | based on [[RFC5649]]: |
In the design of some high assurance cryptographic modules, it is | In the design of some high assurance cryptographic modules, it is | ||
Line 159: | Line 159: | ||
=== Normative References === | === Normative References === | ||
− | + | [[RFC2119]] Bradner, S., "Key words for use in RFCs to Indicate | |
− | Requirement Levels", BCP 14, RFC 2119, March 1997. | + | Requirement Levels", [[BCP14|BCP 14]], [[RFC2119|RFC 2119]], March 1997. |
− | + | [[RFC3370]] Housley, R., "Cryptographic Message Syntax (CMS) | |
− | Algorithms", RFC 3370, August 2002. | + | Algorithms", [[RFC3370|RFC 3370]], August 2002. |
− | + | [[RFC3560]] Housley, R., "Use of the RSAES-OAEP Key Transport | |
Algorithm in Cryptographic Message Syntax (CMS)", RFC | Algorithm in Cryptographic Message Syntax (CMS)", RFC | ||
3560, July 2003. | 3560, July 2003. | ||
− | + | [[RFC4056]] Schaad, J., "Use of the RSASSA-PSS Signature Algorithm in | |
− | Cryptographic Message Syntax (CMS)", RFC 4056, June 2005. | + | Cryptographic Message Syntax (CMS)", [[RFC4056|RFC 4056]], June 2005. |
− | + | [[RFC5083]] Housley, R., "Cryptographic Message Syntax (CMS) | |
− | Authenticated-Enveloped-Data Content Type", RFC 5083, | + | Authenticated-Enveloped-Data Content Type", [[RFC5083|RFC 5083]], |
November 2007. | November 2007. | ||
− | + | [[RFC5084]] Housley, R., "Using AES-CCM and AES-GCM Authenticated | |
Encryption in the Cryptographic Message Syntax (CMS)", | Encryption in the Cryptographic Message Syntax (CMS)", | ||
− | RFC 5084, November 2007. | + | [[RFC5084|RFC 5084]], November 2007. |
− | + | [[RFC5280]] Cooper, D., Santesson, S., Farrell, S., Boeyen, S., | |
Housley, R., and W. Polk, "Internet X.509 Public Key | Housley, R., and W. Polk, "Internet X.509 Public Key | ||
Infrastructure Certificate and Certificate Revocation | Infrastructure Certificate and Certificate Revocation | ||
− | List (CRL) Profile", RFC 5280, May 2008. | + | List (CRL) Profile", [[RFC5280|RFC 5280]], May 2008. |
− | + | [[RFC5649]] Housley, R. and M. Dworkin, "Advanced Encryption Standard | |
− | (AES) Key Wrap with Padding Algorithm", RFC 5649, | + | (AES) Key Wrap with Padding Algorithm", [[RFC5649|RFC 5649]], |
September 2009. | September 2009. | ||
− | + | [[RFC5652]] Housley, R., "Cryptographic Message Syntax (CMS)", STD | |
− | 70, RFC 5652, September 2009. | + | 70, [[RFC5652|RFC 5652]], September 2009. |
− | + | [[RFC5753]] Turner, S. and D. Brown, "Use of Elliptic Curve | |
Cryptography (ECC) Algorithms in Cryptographic Message | Cryptography (ECC) Algorithms in Cryptographic Message | ||
− | Syntax (CMS)", RFC 5753, January 2010. | + | Syntax (CMS)", [[RFC5753|RFC 5753]], January 2010. |
− | + | [[RFC5754]] Turner, S., "Using SHA2 Algorithms with Cryptographic | |
− | Message Syntax", RFC 5754, January 2010. | + | Message Syntax", [[RFC5754|RFC 5754]], January 2010. |
− | + | [[RFC6031]] Turner, S. and R. Housley, "Cryptographic Message Syntax | |
− | (CMS) Symmetric Key Package Content Type", RFC 6031, | + | (CMS) Symmetric Key Package Content Type", [[RFC6031|RFC 6031]], |
December 2010. | December 2010. | ||
− | + | [[RFC6090]] McGrew, D., Igoe, K., and M. Salter, "Fundamental | |
− | Elliptic Curve Cryptography Algorithms", RFC 6090, | + | Elliptic Curve Cryptography Algorithms", [[RFC6090|RFC 6090]], |
February 2011. | February 2011. | ||
Latest revision as of 04:25, 22 October 2020
Internet Engineering Task Force (IETF) S. Turner Request for Comments: 6160 IECA Category: Standards Track April 2011 ISSN: 2070-1721
Algorithms for Cryptographic Message Syntax (CMS) Protection of Symmetric Key Package Content Types
Abstract
This document describes the conventions for using several cryptographic algorithms with the Cryptographic Message Syntax (CMS) to protect the symmetric key package content type. Specifically, it includes conventions necessary to implement SignedData, EnvelopedData, EncryptedData, and AuthEnvelopedData.
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/rfc6160.
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.
Contents
Introduction
This document describes the conventions for using several cryptographic algorithms with the Cryptographic Message Syntax (CMS) RFC5652 to protect the symmetric key package content type defined in RFC6031. Specifically, it includes conventions necessary to implement the following CMS content types: SignedData RFC5652, EnvelopedData RFC5652, EncryptedData RFC5652, and AuthEnvelopedData RFC5083. Familiarity with RFC5083, RFC5652, RFC5753, and RFC6031 is assumed.
This document does not define any new algorithms; instead, it refers to previously defined algorithms.
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.
SignedData
If an implementation supports SignedData, then it MUST support the signature scheme RSA RFC3370 and SHOULD support the signature schemes RSA Probabilistic Signature Scheme (RSASSA-PSS) RFC4056 and Digital Signature Algorithm (DSA) RFC3370. Additionally, implementations MUST support the hash function SHA-256 RFC5754 in concert with these signature schemes, and they SHOULD support the hash function SHA-1 RFC3370. If an implementation supports SignedData, then it MAY support Elliptic Curve Digital Signature Algorithm (ECDSA) RFC6090RFC5753.
EnvelopedData
If an implementation supports EnvelopedData, then it MUST implement key transport, and it MAY implement key agreement.
When key transport is used, RSA encryption RFC3370 MUST be supported, and RSA Encryption Scheme - Optimal Asymmetric Encryption Padding (RSAES-OAEP) RFC3560 SHOULD be supported.
When key agreement is used, Diffie-Hellman (DH) ephemeral-static RFC3370 MUST be supported. When key agreement is used, Elliptic Curve Diffie-Hellman (ECDH) RFC6090RFC5753 MAY be supported.
Regardless of the key management technique choice, implementations MUST support AES-128 Key Wrap with Padding RFC5649 as the content- encryption algorithm. Implementations SHOULD support AES-256 Key Wrap with Padding RFC5649 as the content-encryption algorithm.
When key agreement is used, the same key-wrap algorithm MUST be used for both key and content encryption. If the content-encryption algorithm is AES-128 Key Wrap with Padding, then the key-wrap algorithm MUST be AES-128 Key Wrap with Padding RFC5649. If the content-encryption algorithm is AES-256 Key Wrap with Padding, then the key-wrap algorithm MUST be AES-256 Key Wrap with Padding RFC5649.
EncryptedData
If an implementation supports EncryptedData, then it MUST implement AES-128 Key Wrap with Padding RFC5649 and SHOULD implement AES-256 Key Wrap with Padding RFC5649.
NOTE: EncryptedData requires that keys be managed by other means; therefore, the only algorithm specified is the content-encryption algorithm.
AuthEnvelopedData
If an implementation supports AuthEnvelopedData, then it MUST implement the EnvelopedData recommendations except for the content- encryption algorithm, which, in this case, MUST be AES-GCM RFC5084; the 128-bit version MUST be implemented, and the 256-bit version SHOULD be implemented. Implementations MAY also support AES-CCM RFC5084.
Public Key Sizes
The easiest way to implement SignedData, EnvelopedData, and AuthEnvelopedData is with public key certificates RFC5280. If an implementation supports RSA, RSASSA-PSS, DSA, RSAES-OAEP, or Diffie- Hellman, then it MUST support key lengths from 1024-bit to 2048-bit, inclusive. If an implementation supports ECDSA or ECDH, then it MUST support keys on P-256.
Security Considerations
The security considerations from RFC3370, RFC3560, RFC4056, RFC5083, RFC5084, RFC5649, RFC5652, RFC5753, RFC5754, and RFC6031 apply.
The choice of content-encryption algorithms for this document was based on RFC5649:
In the design of some high assurance cryptographic modules, it is desirable to segregate cryptographic keying material from other data. The use of a specific cryptographic mechanism solely for the protection of cryptographic keying material can assist in this goal.
Unfortunately, there is no AES-GCM or AES-CCM mode that provides the same properties. If an AES-GCM and AES-CCM mode that provides the same properties is defined, then this document will be updated to adopt that algorithm.
[SP800-57] provides comparable bits of security for some algorithms and key sizes. [SP800-57] also provides time frames during which certain numbers of bits of security are appropriate, and some environments may find these time frames useful.
References
Normative References
RFC2119 Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
RFC3370 Housley, R., "Cryptographic Message Syntax (CMS)
Algorithms", RFC 3370, August 2002.
RFC3560 Housley, R., "Use of the RSAES-OAEP Key Transport
Algorithm in Cryptographic Message Syntax (CMS)", RFC 3560, July 2003.
RFC4056 Schaad, J., "Use of the RSASSA-PSS Signature Algorithm in
Cryptographic Message Syntax (CMS)", RFC 4056, June 2005.
RFC5083 Housley, R., "Cryptographic Message Syntax (CMS)
Authenticated-Enveloped-Data Content Type", RFC 5083, November 2007.
RFC5084 Housley, R., "Using AES-CCM and AES-GCM Authenticated
Encryption in the Cryptographic Message Syntax (CMS)", RFC 5084, November 2007.
RFC5280 Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile", RFC 5280, May 2008.
RFC5649 Housley, R. and M. Dworkin, "Advanced Encryption Standard
(AES) Key Wrap with Padding Algorithm", RFC 5649, September 2009.
RFC5652 Housley, R., "Cryptographic Message Syntax (CMS)", STD
70, RFC 5652, September 2009.
RFC5753 Turner, S. and D. Brown, "Use of Elliptic Curve
Cryptography (ECC) Algorithms in Cryptographic Message Syntax (CMS)", RFC 5753, January 2010.
RFC5754 Turner, S., "Using SHA2 Algorithms with Cryptographic
Message Syntax", RFC 5754, January 2010.
RFC6031 Turner, S. and R. Housley, "Cryptographic Message Syntax
(CMS) Symmetric Key Package Content Type", RFC 6031, December 2010.
RFC6090 McGrew, D., Igoe, K., and M. Salter, "Fundamental
Elliptic Curve Cryptography Algorithms", RFC 6090, February 2011.
Informative Reference
[SP800-57] National Institute of Standards and Technology (NIST),
Special Publication 800-57: Recommendation for Key Management - Part 1 (Revised), March 2007.
Author's Address
Sean Turner IECA, Inc. 3057 Nutley Street, Suite 106 Fairfax, VA 22031 USA
EMail: [email protected]