idnits 2.17.00 (12 Aug 2021) /tmp/idnits3348/draft-merkle-tls-brainpool-02.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- -- The draft header indicates that this document updates RFC4492, but the abstract doesn't seem to mention this, which it should. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year (Using the creation date from RFC4492, updated by this document, for RFC5378 checks: 1998-03-18) -- The document seems to lack a disclaimer for pre-RFC5378 work, but may have content which was first submitted before 10 November 2008. If you have contacted all the original authors and they are all willing to grant the BCP78 rights to the IETF Trust, then this is fine, and you can ignore this comment. If not, you may need to add the pre-RFC5378 disclaimer. (See the Legal Provisions document at https://trustee.ietf.org/license-info for more information.) -- The document date (June 24, 2013) is 3252 days in the past. Is this intentional? Checking references for intended status: Informational ---------------------------------------------------------------------------- == Unused Reference: 'RFC2119' is defined on line 142, but no explicit reference was found in the text == Unused Reference: 'RFC6347' is defined on line 158, but no explicit reference was found in the text == Unused Reference: 'RFC6090' is defined on line 204, but no explicit reference was found in the text ** Obsolete normative reference: RFC 4492 (Obsoleted by RFC 8422) ** Obsolete normative reference: RFC 5246 (Obsoleted by RFC 8446) ** Obsolete normative reference: RFC 6347 (Obsoleted by RFC 9147) Summary: 3 errors (**), 0 flaws (~~), 4 warnings (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group J. Merkle 3 Internet-Draft secunet Security Networks 4 Updates: 4492 (if approved) M. Lochter 5 Intended status: Informational Bundesamt fuer Sicherheit in der 6 Expires: December 26, 2013 Informationstechnik (BSI) 7 June 24, 2013 9 ECC Brainpool Curves for Transport Layer Security (TLS) 10 draft-merkle-tls-brainpool-02 12 Abstract 14 This document specifies the use of several ECC Brainpool curves for 15 authentication and key exchange in the Transport Layer Security (TLS) 16 protocol. 18 Status of This Memo 20 This Internet-Draft is submitted in full conformance with the 21 provisions of BCP 78 and BCP 79. 23 Internet-Drafts are working documents of the Internet Engineering 24 Task Force (IETF). Note that other groups may also distribute 25 working documents as Internet-Drafts. The list of current Internet- 26 Drafts is at http://datatracker.ietf.org/drafts/current/. 28 Internet-Drafts are draft documents valid for a maximum of six months 29 and may be updated, replaced, or obsoleted by other documents at any 30 time. It is inappropriate to use Internet-Drafts as reference 31 material or to cite them other than as "work in progress." 33 This Internet-Draft will expire on December 26, 2013. 35 Copyright Notice 37 Copyright (c) 2013 IETF Trust and the persons identified as the 38 document authors. All rights reserved. 40 This document is subject to BCP 78 and the IETF Trust's Legal 41 Provisions Relating to IETF Documents 42 (http://trustee.ietf.org/license-info) in effect on the date of 43 publication of this document. Please review these documents 44 carefully, as they describe your rights and restrictions with respect 45 to this document. Code Components extracted from this document must 46 include Simplified BSD License text as described in Section 4.e of 47 the Trust Legal Provisions and are provided without warranty as 48 described in the Simplified BSD License. 50 Table of Contents 52 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 53 2. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 54 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 5 55 4. References . . . . . . . . . . . . . . . . . . . . . . . . . . 6 56 4.1. Normative References . . . . . . . . . . . . . . . . . . . 6 57 4.2. Informative References . . . . . . . . . . . . . . . . . . 6 58 Appendix A. Test Vectors . . . . . . . . . . . . . . . . . . . . . 8 59 A.1. 256 Bit Curve . . . . . . . . . . . . . . . . . . . . . . . 8 60 A.2. 384 Bit Curve . . . . . . . . . . . . . . . . . . . . . . . 9 61 A.3. 512 Bit Curve . . . . . . . . . . . . . . . . . . . . . . . 9 63 1. Introduction 65 In [RFC5639], a new set of elliptic curve groups over finite prime 66 fields for use in cryptographic applications was specified. These 67 groups, denoted as ECC Brainpool curves, were generated in a 68 verifiably pseudo-random way and comply with the security 69 requirements of relevant standards from ISO [ISO1] [ISO2], ANSI 70 [ANSI1], NIST [FIPS], and SecG [SEC2]. 72 Usage of elliptic curves for authentication and key agreement in TLS 73 1.0 and TLS 1.1 is defined in [RFC4492]. While the ASN.1 object 74 identifiers defined in [RFC5639] already allow usage of the ECC 75 Brainpool curves for TLS (client or server) authentication through 76 reference in X.509 certificates according to [RFC3279] and [RFC5480] 77 , their negotiation for key exchange according to [RFC4492] requires 78 the definition and assignment of additional NamedCurve IDs. This 79 document specifies such values for three curves from [RFC5639]. 81 Test vectors for a Diffie-Hellman key exchange using these ECC 82 Brainpool curves are provided in Appendix A 84 2. Security Considerations 86 The security considerations of [RFC5246] apply accordingly. 88 The confidentiality, authenticity and integrity of the TLS 89 communication is limited by the weakest cryptographic primitive 90 applied. In order to achieve a maximum security level when using one 91 of the elliptic curves from Table 1 for authentication and / or key 92 exchange in TLS, the key derivation function, the algorithms and key 93 lengths of symmetric encryption and message authentication as well as 94 the algorithm, bit length and hash function used for signature 95 generation should be chosen according to the recommendations of 96 [NIST800-57] and [RFC5639]. Furthermore, the private Diffie-Hellman 97 keys should be selected with the same bit length as the order of the 98 group generated by the base point G and with approximately maximum 99 entropy. 101 Implementations of elliptic curve cryptography for TLS may be 102 susceptible to side-channel attacks. Particular care should be taken 103 for implementations that internally transform curve points to points 104 on the corresponding "twisted curve", using the map (x',y') = (x*Z^2, 105 y*Z^3) with the coefficient Z specified for that curve in [RFC5639], 106 in order to take advantage of an an efficient arithmetic based on the 107 twisted curve's special parameters (A = -3): although the twisted 108 curve itself offers the same level of security as the corresponding 109 random curve (through mathematical equivalence), an arithmetic based 110 on small curve parameters may be harder to protect against side- 111 channel attacks. General guidance on resistence of elliptic curve 112 cryptography implementations against side-channel-attacks is given in 113 [BSI1] and [HMV]. 115 3. IANA Considerations 117 IANA is requested to assign numbers for the ECC Brainpool curves, 118 defined in [RFC5639], found in Table 1 in the Transport Layer 119 Security (TLS) Parameters NamedCurve registry [IANA-TLS]. These 120 curves are suitability for use with DTLS. 122 +-------+-----------------+---------+-----------+ 123 | Value | Description | DTLS-OK | Reference | 124 +-------+-----------------+---------+-----------+ 125 | TBD1 | brainpoolP256r1 | Y | This doc | 126 | | | | | 127 | TBD2 | brainpoolP384r1 | Y | This doc | 128 | | | | | 129 | TBD3 | brainpoolP512r1 | Y | This doc | 130 +-------+-----------------+---------+-----------+ 132 Table 1 134 4. References 136 4.1. Normative References 138 [IANA-TLS] Internet Assigned Numbers Authority, "Transport Layer 139 Security (TLS) Parameters", . 142 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 143 Requirement Levels", BCP 14, RFC 2119, March 1997. 145 [RFC4492] Blake-Wilson, S., Bolyard, N., Gupta, V., Hawk, C., and 146 B. Moeller, "Elliptic Curve Cryptography (ECC) Cipher 147 Suites for Transport Layer Security (TLS)", RFC 4492, 148 May 2006. 150 [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer 151 Security (TLS) Protocol Version 1.2", RFC 5246, 152 August 2008. 154 [RFC5639] Lochter, M. and J. Merkle, "Elliptic Curve Cryptography 155 (ECC) Brainpool Standard Curves and Curve Generation", 156 RFC 5639, March 2010. 158 [RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer 159 Security Version 1.2", RFC 6347, January 2012. 161 4.2. Informative References 163 [ANSI1] American National Standards Institute, "Public Key 164 Cryptography For The Financial Services Industry: The 165 Elliptic Curve Digital Signature Algorithm (ECDSA)", 166 ANSI X9.62, 2005. 168 [BSI1] Bundesamt fuer Sicherheit in der Informationstechnik, 169 "Minimum Requirements for Evaluating Side-Channel 170 Attack Resistance of Elliptic Curve Implementations", 171 July 2011. 173 [FIPS] National Institute of Standards and Technology, 174 "Digital Signature Standard (DSS)", FIPS PUB 186-2, 175 December 1998. 177 [HMV] Hankerson, D., Menezes, A., and S. Vanstone, "Guide to 178 Elliptic Curve Cryptography", Springer Verlag, 2004. 180 [ISO1] International Organization for Standardization, 181 "Information Technology - Security Techniques - Digital 182 Signatures with Appendix - Part 3: Discrete Logarithm 183 Based Mechanisms", ISO/IEC 14888-3, 2006. 185 [ISO2] International Organization for Standardization, 186 "Information Technology - Security Techniques - 187 Cryptographic Techniques Based on Elliptic Curves - 188 Part 2: Digital signatures", ISO/IEC 15946-2, 2002. 190 [NIST800-57] National Institute of Standards and Technology, 191 "Recommendation for Key Management - Part 1: General 192 (Revised)", NIST Special Publication 800-57, 193 March 2007. 195 [RFC3279] Bassham, L., Polk, W., and R. Housley, "Algorithms and 196 Identifiers for the Internet X.509 Public Key 197 Infrastructure Certificate and Certificate Revocation 198 List (CRL) Profile", RFC 3279, April 2002. 200 [RFC5480] Turner, S., Brown, D., Yiu, K., Housley, R., and T. 201 Polk, "Elliptic Curve Cryptography Subject Public Key 202 Information", RFC 5480, March 2009. 204 [RFC6090] McGrew, D., Igoe, K., and M. Salter, "Fundamental 205 Elliptic Curve Cryptography Algorithms", RFC 6090, 206 February 2011. 208 [SEC1] Certicom Research, "Elliptic Curve Cryptography", 209 Standards for Efficient Cryptography (SEC) 1, 210 September 2000. 212 [SEC2] Certicom Research, "Recommended Elliptic Curve Domain 213 Parameters", Standards for Efficient Cryptography 214 (SEC) 2, September 2000. 216 Appendix A. Test Vectors 218 This section provides some test vectors for example Diffie-Hellman 219 key exchanges using each of the curves defined in Table 1 . In all 220 of the following sections the following notation is used: 222 d_A: the secret key of party A 224 x_qA: the x-coordinate of the public key of party A 226 y_qA: the y-coordinate of the public key of party A 228 d_B: the secret key of party B 230 x_qB: the x-coordinate of the public key of party B 232 y_qB: the y-coordinate of the public key of party B 234 x_Z: the x-coordinate of the shared secret that results from 235 completion of the Diffie-Hellman computation, i.e. the hex 236 representation of the pre-master secret 238 y_Z: the y-coordinate of the shared secret that results from 239 completion of the Diffie-Hellman computation 241 The field elements x_qA, y_qA, x_qB, y_qB, x_Z, y_Z are represented 242 as hexadecimal values using the FieldElement-to-OctetString 243 conversion method specified in [SEC1]. 245 A.1. 256 Bit Curve 247 Curve brainpoolP256r1 249 dA = 250 81DB1EE100150FF2EA338D708271BE38300CB54241D79950F77B063039804F1D 252 x_qA = 253 44106E913F92BC02A1705D9953A8414DB95E1AAA49E81D9E85F929A8E3100BE5 255 y_qA = 256 8AB4846F11CACCB73CE49CBDD120F5A900A69FD32C272223F789EF10EB089BDC 258 dB = 259 55E40BC41E37E3E2AD25C3C6654511FFA8474A91A0032087593852D3E7D76BD3 261 x_qB = 262 8D2D688C6CF93E1160AD04CC4429117DC2C41825E1E9FCA0ADDD34E6F1B39F7B 263 y_qB = 264 990C57520812BE512641E47034832106BC7D3E8DD0E4C7F1136D7006547CEC6A 266 x_Z = 267 89AFC39D41D3B327814B80940B042590F96556EC91E6AE7939BCE31F3A18BF2B 269 y_Z = 270 49C27868F4ECA2179BFD7D59B1E3BF34C1DBDE61AE12931648F43E59632504DE 272 A.2. 384 Bit Curve 274 Curve brainpoolP384r1 276 dA = 1E20F5E048A5886F1F157C74E91BDE2B98C8B52D58E5003D57053FC4B0BD6 277 5D6F15EB5D1EE1610DF870795143627D042 279 x_qA = 68B665DD91C195800650CDD363C625F4E742E8134667B767B1B47679358 280 8F885AB698C852D4A6E77A252D6380FCAF068 282 y_qA = 55BC91A39C9EC01DEE36017B7D673A931236D2F1F5C83942D049E3FA206 283 07493E0D038FF2FD30C2AB67D15C85F7FAA59 285 dB = 032640BC6003C59260F7250C3DB58CE647F98E1260ACCE4ACDA3DD869F74E 286 01F8BA5E0324309DB6A9831497ABAC96670 288 x_qB = 4D44326F269A597A5B58BBA565DA5556ED7FD9A8A9EB76C25F46DB69D19 289 DC8CE6AD18E404B15738B2086DF37E71D1EB4 291 y_qB = 62D692136DE56CBE93BF5FA3188EF58BC8A3A0EC6C1E151A21038A42E91 292 85329B5B275903D192F8D4E1F32FE9CC78C48 294 x_Z = 0BD9D3A7EA0B3D519D09D8E48D0785FB744A6B355E6304BC51C229FBBCE2 295 39BBADF6403715C35D4FB2A5444F575D4F42 297 y_Z = 0DF213417EBE4D8E40A5F76F66C56470C489A3478D146DECF6DF0D94BAE9 298 E598157290F8756066975F1DB34B2324B7BD 300 A.3. 512 Bit Curve 302 Curve brainpoolP512r1 304 dA = 16302FF0DBBB5A8D733DAB7141C1B45ACBC8715939677F6A56850A38BD87B 305 D59B09E80279609FF333EB9D4C061231FB26F92EEB04982A5F1D1764CAD5766542 306 2 308 x_qA = 0A420517E406AAC0ACDCE90FCD71487718D3B953EFD7FBEC5F7F27E28C6 309 149999397E91E029E06457DB2D3E640668B392C2A7E737A7F0BF04436D11640FD0 310 9FD 311 y_qA = 72E6882E8DB28AAD36237CD25D580DB23783961C8DC52DFA2EC138AD472 312 A0FCEF3887CF62B623B2A87DE5C588301EA3E5FC269B373B60724F5E82A6AD147F 313 DE7 315 dB = 230E18E1BCC88A362FA54E4EA3902009292F7F8033624FD471B5D8ACE49D1 316 2CFABBC19963DAB8E2F1EBA00BFFB29E4D72D13F2224562F405CB80503666B2542 317 9 319 x_qB = 9D45F66DE5D67E2E6DB6E93A59CE0BB48106097FF78A081DE781CDB31FC 320 E8CCBAAEA8DD4320C4119F1E9CD437A2EAB3731FA9668AB268D871DEDA55A54731 321 99F 323 y_qB = 2FDC313095BCDD5FB3A91636F07A959C8E86B5636A1E930E8396049CB48 324 1961D365CC11453A06C719835475B12CB52FC3C383BCE35E27EF194512B7187628 325 5FA 327 x_Z = A7927098655F1F9976FA50A9D566865DC530331846381C87256BAF322624 328 4B76D36403C024D7BBF0AA0803EAFF405D3D24F11A9B5C0BEF679FE1454B21C4CD 329 1F 331 y_Z = 7DB71C3DEF63212841C463E881BDCF055523BD368240E6C3143BD8DEF8B3 332 B3223B95E0F53082FF5E412F4222537A43DF1C6D25729DDB51620A832BE6A26680 333 A2 335 Authors' Addresses 337 Johannes Merkle 338 secunet Security Networks 339 Mergenthaler Allee 77 340 65760 Eschborn 341 Germany 343 Phone: +49 201 5454 3091 344 EMail: johannes.merkle@secunet.com 346 Manfred Lochter 347 Bundesamt fuer Sicherheit in der Informationstechnik (BSI) 348 Postfach 200363 349 53133 Bonn 350 Germany 352 Phone: +49 228 9582 5643 353 EMail: manfred.lochter@bsi.bund.de