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diff --git a/doc/protocol/draft-badra-tls-psk-new-mac-aes-gcm-00.txt b/doc/protocol/draft-badra-tls-psk-new-mac-aes-gcm-00.txt deleted file mode 100644 index c0eb4c19c4..0000000000 --- a/doc/protocol/draft-badra-tls-psk-new-mac-aes-gcm-00.txt +++ /dev/null @@ -1,539 +0,0 @@ -TLS Working Group Mohamad Badra -Internet Draft LIMOS Laboratory -Intended status: Standards Track March 29, 2008 -Expires: September 2008 - - - - Pre-Shared Key Cipher Suites for Transport Layer Security - with SHA-256/384 and AES Galois Counter Mode - draft-badra-tls-psk-new-mac-aes-gcm-00.txt - - -Status of this Memo - - By submitting this Internet-Draft, each author represents that any - applicable patent or other IPR claims of which he or she is aware - have been or will be disclosed, and any of which he or she becomes - aware will be disclosed, in accordance with Section 6 of BCP 79. - - Internet-Drafts are working documents of the Internet Engineering - Task Force (IETF), its areas, and its working groups. Note that - other groups may also distribute working documents as Internet- - Drafts. - - 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." - - The list of current Internet-Drafts can be accessed at - http://www.ietf.org/ietf/1id-abstracts.txt - - The list of Internet-Draft Shadow Directories can be accessed at - http://www.ietf.org/shadow.html - - This Internet-Draft will expire on September 29, 2008. - -Copyright Notice - - Copyright (C) The IETF Trust (2008). - -Abstract - - RFC 4279 and RFC 4785 describe pre-shared key cipher suites for - Transport Layer Security (TLS). However, all those cipher suites - use SHA-1 as their MAC algorithm. This document describes a set of - cipher suites for TLS/DTLS which uses stronger digest algorithms - - - - -Badra Expires September 29, 2008 [Page 1] - -Internet-Draft ECDHE_PSK Cipher Suites for TLS March 2008 - - - (i.e. SHA-256 or SHA-384) and another which uses AES in Galois - Counter Mode (GCM). - -Table of Contents - - - 1. Introduction...................................................3 - 1.1. Conventions used in this document.........................3 - 2. PSK, DHE_PSK and RSA_PSK Key Exchange Algorithms with AES-GCM..3 - 3. PSK, DHE_PSK and RSA_PSK Key Exchange with SHA-256/384.........4 - 3.1. PSK Key Exchange Algorithm with SHA-256/384...............4 - 3.2. DHE_PSK Key Exchange Algorithm with SHA-256/384...........5 - 3.3. RSA_PSK Key Exchange Algorithm with SHA-256/384...........5 - 4. TLS Versions...................................................6 - 5. Security Considerations........................................6 - 5.1. Counter Reuse with GCM....................................6 - 5.2. Recommendations for Multiple Encryption Processors........6 - 6. IANA Considerations............................................7 - 7. Acknowledgments................................................8 - 8. References.....................................................8 - 8.1. Normative References......................................8 - 8.2. Informative References....................................9 - Author's Addresses................................................9 - Intellectual Property Statement..................................10 - Disclaimer of Validity...........................................10 - - - - - - - - - - - - - - - - - - - - - - - - -Badra Expires September 29, 2008 [Page 2] - -Internet-Draft ECDHE_PSK Cipher Suites for TLS March 2008 - - -1. Introduction - - This document describes the use of AES [AES] in Galois Counter Mode - (GCM) [GCM] (AES-GCM) with various pre-shared key (PSK) key exchange - mechanisms ([RFC4279] and [RFC4785]) as a ciphersuite for Transport - Layer Security (TLS). AES-GCM is not only efficient and secure, but - hardware implementations can achieve high speeds with low cost and - low latency, because the mode can be pipelined. - - This document also specifies PSK cipher suites for TLS which replace - SHA-256 and SHA-384 rather than SHA-1. RFC 4279 [RFC4279] and RFC - 4785 [RFC4785] describe pre-shared key (PSK) cipher suites for TLS. - However, all of the RFC 4279 and the RFC 4785 suites use HMAC-SHA1 - as their MAC algorithm. Due to recent analytic work on SHA-1 - [Wang05], the IETF is gradually moving away from SHA-1 and towards - stronger hash algorithms. - - [I-D.ietf-tls-ecc-new-mac] and [I-D.ietf-tls-rsa-aes-gcm] provide - support for GCM with other key establishment methods. - -1.1. Conventions used in this document - - 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]. - -2. PSK, DHE_PSK and RSA_PSK Key Exchange Algorithms with AES-GCM - - The following eight cipher suites use the new authenticated - encryption modes defined in TLS 1.2 with AES in Galois Counter Mode - (GCM) [GCM]: - - CipherSuite TLS_PSK_WITH_AES_128_GCM_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_258_GCM_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_128_GCM_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_256_GCM_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_128_GCM_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_256_GCM_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_128_GCM_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_256_GCM_SHA384 = {0xXX,0xXX}; - - These cipher suites use authenticated encryption with additional - data algorithms AEAD_AES_128_GCM and AEAD_AES_256_GCM described in - RFC 5116. The "nonce" input to the AEAD algorithm SHALL be 12 bytes - long, and is "partially implicit" (see Section 3.2.1 of RFC 5116). - Part of the nonce is generated as part of the handshake process and - is static for the entire session and part is carried in each packet. - - -Badra Expires September 29, 2008 [Page 3] - -Internet-Draft ECDHE_PSK Cipher Suites for TLS March 2008 - - - struct { - opaque salt[4]; - opaque explicit_nonce_part[8]; - } GCMNonce. - - The salt value is either the client_write_IV if the client is - sending or the server_write_IV if the server is sending. These IVs - SHALL be 4 bytes long. Therefore, for all the algorithms defined in - this section, SecurityParameters.fixed_iv_length=4. - - The explicit_nonce_part is chosen by the sender and included in the - packet. Each value of the explicit_nonce_part MUST be distinct from - all other values, for any fixed key. Failure to meet this - uniqueness requirement can significantly degrade security. The - explicit_nonce_part is carried in the IV field of the - GenericAEADCipher structure. Therefore, for all the algorithms - defined in this section, SecurityParameters.record_iv_length=8. - - In the case of TLS the counter MAY be the 64-bit sequence number. - In the case of Datagram TLS [RFC4347] the counter MAY be formed from - the concatenation of the 16-bit epoch with the 48-bit sequence - number. - - The PRF algorithms SHALL be as follows: - - For ciphersuites ending in _SHA256 the hash function is SHA256. - - For ciphersuites ending in _SHA384 the hash function is SHA384. - -3. PSK, DHE_PSK and RSA_PSK Key Exchange with SHA-256/384 - - The cipher suites described in this section use AES [AES] in CBC - [CBC] mode with an HMAC-based MAC. - -3.1. PSK Key Exchange Algorithm with SHA-256/384 - - CipherSuite TLS_PSK_WITH_AES_128_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_256_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_128_CBC_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_256_CBC_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_NULL_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_NULL_SHA384 = {0xXX,0xXX}; - - The above six cipher suites are the same as the corresponding cipher - suites in RFC 4279 and RFC 4785 (TLS_PSK_WITH_AES_128_CBC_SHA, - TLS_PSK_WITH_AES_256_CBC_SHA, and TLS_PSK_WITH_NULL_SHA) except for - - - -Badra Expires September 29, 2008 [Page 4] - -Internet-Draft ECDHE_PSK Cipher Suites for TLS March 2008 - - - the hash and PRF algorithms, which are SHA-256 and SHA-384 [SHS] as - follows. - - Cipher Suite MAC PRF - ------------ --- --- - TLS_PSK_WITH_AES_128_CBC_SHA256 HMAC-SHA-256 P_SHA-256 - TLS_PSK_WITH_AES_128_CBC_SHA384 HMAC-SHA-384 P_SHA-384 - TLS_PSK_WITH_AES_256_CBC_SHA256 HMAC-SHA-256 P_SHA-256 - TLS_PSK_WITH_AES_256_CBC_SHA384 HMAC-SHA-384 P_SHA-384 - TLS_PSK_WITH_NULL_SHA256 HMAC-SHA-256 P_SHA-256 - TLS_PSK_WITH_NULL_SHA384 HMAC-SHA-384 P_SHA-384 - -3.2. DHE_PSK Key Exchange Algorithm with SHA-256/384 - - CipherSuite TLS_DHE_PSK_WITH_AES_128_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_128_CBC_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_256_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_256_CBC_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_NULL_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_NULL_SHA384 = {0xXX,0xXX}; - - The above six cipher suites are the same as the corresponding cipher - suites in RFC 4279 and RFC 4785 (TLS_DHE_PSK_WITH_AES_128_CBC_SHA, - TLS_DHE_PSK_WITH_AES_256_CBC_SHA, and TLS_DHE_PSK_WITH_NULL_SHA) - except for the hash and PRF algorithms, which are SHA-256 and SHA- - 384 [SHS] as follows. - - Cipher Suite MAC PRF - ------------ --- --- - TLS_DHE_PSK_WITH_AES_128_CBC_SHA256 HMAC-SHA-256 P_SHA-256 - TLS_DHE_PSK_WITH_AES_128_CBC_SHA384 HMAC-SHA-384 P_SHA-384 - TLS_DHE_PSK_WITH_AES_256_CBC_SHA256 HMAC-SHA-256 P_SHA-256 - TLS_DHE_PSK_WITH_AES_256_CBC_SHA384 HMAC-SHA-384 P_SHA-384 - -3.3. RSA_PSK Key Exchange Algorithm with SHA-256/384 - - CipherSuite TLS_RSA_PSK_WITH_AES_128_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_128_CBC_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_256_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_256_CBC_SHA384 = {0xXX,0xXX}; - - The above four cipher suites are the same as the corresponding - cipher suites in RFC 4279 and RFC 4785 - (TLS_RSA_PSK_WITH_AES_128_CBC_SHA, TLS_RSA_PSK_WITH_AES_256_CBC_SHA, - and TLS_RSA_PSK_WITH_NULL_SHA) except for the hash and PRF - algorithms, which are SHA-256 and SHA-384 [SHS] as follows. - - - -Badra Expires September 29, 2008 [Page 5] - -Internet-Draft ECDHE_PSK Cipher Suites for TLS March 2008 - - - Cipher Suite MAC PRF - ------------ --- --- - TLS_RSA_PSK_WITH_AES_128_CBC_SHA256 HMAC-SHA-256 P_SHA-256 - TLS_RSA_PSK_WITH_AES_128_CBC_SHA384 HMAC-SHA-384 P_SHA-384 - TLS_RSA_PSK_WITH_AES_256_CBC_SHA256 HMAC-SHA-256 P_SHA-256 - TLS_RSA_PSK_WITH_AES_256_CBC_SHA384 HMAC-SHA-384 P_SHA-384 - -4. TLS Versions - - Because these cipher suites depend on features available only in TLS - 1.2 (PRF flexibility and combined authenticated encryption cipher - modes), they MUST NOT be negotiated by older versions of TLS. - Clients MUST NOT offer these cipher suites if they do not offer TLS - 1.2 or later. Servers which select an earlier version of TLS MUST - NOT select one of these cipher suites. Because TLS has no way for - the client to indicate that it supports TLS 1.2 but not earlier, a - non-compliant server might potentially negotiate TLS 1.1 or earlier - and select one of the cipher suites in this document. Clients MUST - check the TLS version and generate a fatal "illegal_parameter" alert - if they detect an incorrect version. - -5. Security Considerations - - The security considerations in [I-D.ietf-tls-rfc4346-bis], RFC 4279 - and RFC 4785 apply to this document as well. The remainder of this - section describes security considerations specific to the cipher - suites described in this document. - -5.1. Counter Reuse with GCM - - AES-GCM is only secure if the counter is never reused. The IV - construction algorithm above is designed to ensure that this cannot - happen. - -5.2. Recommendations for Multiple Encryption Processors - - If multiple cryptographic processors are in use by the sender, then - the sender MUST ensure that, for a particular key, each value of the - explicit_nonce_part used with that key is distinct. In this case - each encryption processor SHOULD include in the explicit_nonce_part - a fixed value that is distinct for each processor. The recommended - format is - - explicit_nonce_part = FixedDistinct || Variable - - where the FixedDistinct field is distinct for each encryption - processor, but is fixed for a given processor, and the Variable - - -Badra Expires September 29, 2008 [Page 6] - -Internet-Draft ECDHE_PSK Cipher Suites for TLS March 2008 - - - field is distinct for each distinct nonce used by a particular - encryption processor. When this method is used, the FixedDistinct - fields used by the different processors MUST have the same length. - - In the terms of Figure 2 in [RFC5116], the Salt is the Fixed-Common - part of the nonce (it is fixed, and it is common across all - encryption processors), the FixedDistinct field exactly corresponds - to the Fixed-Distinct field, and the Variable field corresponds to - the Counter field, and the explicit part exactly corresponds to the - - explicit_nonce_part. - - For clarity, we provide an example for TLS in which there are two - distinct encryption processors, each of which uses a one-byte - FixedDistinct field: - - Salt = eedc68dc - FixedDistinct = 01 (for the first encryption processor) - FixedDistinct = 02 (for the second encryption processor) - - The GCMnonces generated by the first encryption processor, and their - corresponding explicit_nonce_parts, are: - - GCMNonce explicit_nonce_part - ------------------------ -------------------- - eedc68dc0100000000000000 0100000000000000 - eedc68dc0100000000000001 0100000000000001 - eedc68dc0100000000000002 0100000000000002 - ... - - The GCMnonces generated by the second encryption processor, and - their corresponding explicit_nonce_parts, are - - GCMNonce explicit_nonce_part - ------------------------ -------------------- - eedc68dc0200000000000000 0200000000000000 - eedc68dc0200000000000001 0200000000000001 - eedc68dc0200000000000002 0200000000000002 - ... - -6. IANA Considerations - - IANA has assigned the following values for the cipher suites defined - in this document: - - CipherSuite TLS_PSK_WITH_AES_128_GCM_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_258_GCM_SHA256 = {0xXX,0xXX}; - - -Badra Expires September 29, 2008 [Page 7] - -Internet-Draft ECDHE_PSK Cipher Suites for TLS March 2008 - - - CipherSuite TLS_PSK_WITH_AES_128_GCM_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_256_GCM_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_128_GCM_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_256_GCM_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_128_GCM_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_256_GCM_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_128_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_256_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_128_CBC_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_AES_256_CBC_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_NULL_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_PSK_WITH_NULL_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_128_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_128_CBC_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_256_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_AES_256_CBC_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_NULL_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_DHE_PSK_WITH_NULL_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_128_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_128_CBC_SHA384 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_256_CBC_SHA256 = {0xXX,0xXX}; - CipherSuite TLS_RSA_PSK_WITH_AES_256_CBC_SHA384 = {0xXX,0xXX}; - -7. Acknowledgments - - This draft borrows heavily from [I-D.ietf-tls-ecc-new-mac] and [I- - D.ietf-tls-rsa-aes-gcm]. - -8. References - -8.1. Normative References - - [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate - Requirement Levels", BCP 14, RFC 2119, March 1997. - - [I-D.ietf-tls-rfc4346-bis] - Dierks, T. and E. Rescorla, "The Transport Layer Security - (TLS) Protocol Version 1.2", draft-ietf-tls-rfc4346-bis- - 10, work in progress, March 2008. - - [RFC5116] McGrew, D., "An Interface and Algorithms for Authenticated - Encryption", RFC 5116, January 2008. - - [RFC4279] Eronen, P. and H. Tschofenig, "Pre-Shared Key Ciphersuites - for Transport Layer Security (TLS)", RFC 4279, December - 2005. - - - -Badra Expires September 29, 2008 [Page 8] - -Internet-Draft ECDHE_PSK Cipher Suites for TLS March 2008 - - - [RFC4785] Blumenthal, U., Goel, P., "Pre-Shared Key (PSK) - Ciphersuites with NULL Encryption for Transport Layer - Security (TLS)", RFC 4785, January 2007. - - [AES] National Institute of Standards and Technology, - "Specification for the Advanced Encryption Standard - (AES)", FIPS 197, November 2001. - - [SHS] National Institute of Standards and Technology, "Secure - Hash Standard", FIPS 180-2, August 2002. - - [CBC] National Institute of Standards and Technology, - "Recommendation for Block Cipher Modes of Operation - - Methods and Techniques", SP 800-38A, December 2001. - - [GCM] National Institute of Standards and Technology, - "Recommendation for Block Cipher Modes of Operation: - Galois;/Counter Mode (GCM) for Confidentiality and - Authentication", SP 800-38D, November 2007. - -8.2. Informative References - - [Wang05] Wang, X., Yin, Y., and H. Yu, "Finding Collisions in the - Full SHA-1", CRYPTO 2005, August 2005. - - [RFC4347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer - Security", RFC 4347, April 2006. - - [I-D.ietf-tls-ecc-new-mac] - Rescorla, E., "TLS Elliptic Curve Cipher Suites with SHA- - 256/384 and AES Galois Counter Mode", draft-ietf-tls-ecc- - new-mac-04 (work in progress), February 2008. - - [I-D.ietf-tls-rsa-aes-gcm] - Salowey, J., A. Choudhury, and C. McGrew, "RSA based AES- - GCM Cipher Suites for TLS", draft-ietf-tls-rsa-aes-gcm-02 - (work in progress), February 2008. - -Author's Addresses - - Mohamad Badra - LIMOS Laboratory - UMR6158, CNRS - France - - Email: badra@isima.fr - - - - -Badra Expires September 29, 2008 [Page 9] - -Internet-Draft ECDHE_PSK Cipher Suites for TLS March 2008 - - -Intellectual Property Statement - - The IETF takes no position regarding the validity or scope of any - Intellectual Property Rights or other rights that might be claimed - to pertain to the implementation or use of the technology described - in this document or the extent to which any license under such - rights might or might not be available; nor does it represent that - it has made any independent effort to identify any such rights. - Information on the procedures with respect to rights in RFC - documents can be found in BCP 78 and BCP 79. - - Copies of IPR disclosures made to the IETF Secretariat and any - assurances of licenses to be made available, or the result of an - attempt made to obtain a general license or permission for the use - of such proprietary rights by implementers or users of this - specification can be obtained from the IETF on-line IPR repository - at http://www.ietf.org/ipr. - - The IETF invites any interested party to bring to its attention any - copyrights, patents or patent applications, or other proprietary - rights that may cover technology that may be required to implement - this standard. Please address the information to the IETF at - ietf-ipr@ietf.org. - -Disclaimer of Validity - - This document and the information contained herein are provided on - an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE - REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE - IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL - WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY - WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE - ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS - FOR A PARTICULAR PURPOSE. - -Copyright Statement - - Copyright (C) The IETF Trust (2008). - - This document is subject to the rights, licenses and restrictions - contained in BCP 78, and except as set forth therein, the authors - retain all their rights. - -Acknowledgment - - Funding for the RFC Editor function is currently provided by the - Internet Society. - - -Badra Expires September 29, 2008 [Page 10] - |