Network Working Group R. Tse Internet-Draft Ribose Updates: 4880, 6637 (if approved) W. Wong Intended status: Standards Track Hang Seng Management College Expires: March 2, 2018 August 29, 2017 OSCCA Extensions For OpenPGP draft-openpgp-oscca-00 Abstract This document enables OpenPGP (RFC4880) usage in an compliant manner with OSCCA regulations for use within China. Specifically, it extends OpenPGP to support the usage of SM2, SM3 and SM4 algorithms. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. 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." This Internet-Draft will expire on March 2, 2018. Copyright Notice Copyright (c) 2017 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 Tse & Wong Expires March 2, 2018 [Page 1]

Internet-Draft August 2017 the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Conventions Used in This Document . . . . . . . . . . . . . . 4 2.1. Definitions . . . . . . . . . . . . . . . . . . . . . . . 4 3. SM2 ECC Algorithms . . . . . . . . . . . . . . . . . . . . . 4 3.1. SM2 Digital Signature Algorithm . . . . . . . . . . . . . 4 3.2. SM2 Key Exchange Protocol . . . . . . . . . . . . . . . . 5 3.3. SM2 Public Key Encryption . . . . . . . . . . . . . . . . 5 3.4. Recommended SM2 Curve . . . . . . . . . . . . . . . . . . 6 3.4.1. Definitions . . . . . . . . . . . . . . . . . . . . . 6 3.4.2. Elliptic Curve Formula . . . . . . . . . . . . . . . 6 3.4.3. Curve Parameters . . . . . . . . . . . . . . . . . . 6 4. SM3 Hash Algorithm . . . . . . . . . . . . . . . . . . . . . 7 5. SM4 Symmetric Encryption Algorithm . . . . . . . . . . . . . 7 6. Supported Algorithms . . . . . . . . . . . . . . . . . . . . 7 6.1. Public Key Algorithms . . . . . . . . . . . . . . . . . . 8 6.2. Symmetric Key Algorithms . . . . . . . . . . . . . . . . 8 6.3. Hash Algorithms . . . . . . . . . . . . . . . . . . . . . 8 7. Conversion Primitives . . . . . . . . . . . . . . . . . . . . 9 8. SM2 Key Derivation Function . . . . . . . . . . . . . . . . . 9 8.1. Prerequisites . . . . . . . . . . . . . . . . . . . . . . 9 8.2. Inputs . . . . . . . . . . . . . . . . . . . . . . . . . 9 8.3. Output . . . . . . . . . . . . . . . . . . . . . . . . . 9 8.4. Pseudocode . . . . . . . . . . . . . . . . . . . . . . . 9 9. Encoding of Public and Private Keys . . . . . . . . . . . . . 10 9.1. Public-Key Packet Formats . . . . . . . . . . . . . . . . 10 9.2. Secret-Key Packet Formats . . . . . . . . . . . . . . . . 11 10. Message Encoding with Public Keys . . . . . . . . . . . . . . 11 10.1. Public-Key Encrypted Session Key Packets (Tag 1) . . . . 11 10.2. Signature Packet (Tag 2) . . . . . . . . . . . . . . . . 12 10.2.1. Version 3 Signature Packet Format . . . . . . . . . 12 10.2.2. Version 4 Signature Packet Format . . . . . . . . . 12 11. SM2 ECC Curve OID . . . . . . . . . . . . . . . . . . . . . . 12 12. Compatibility Profiles . . . . . . . . . . . . . . . . . . . 13 12.1. OSCCA Compliant Profile . . . . . . . . . . . . . . . . 13 13. Security Considerations . . . . . . . . . . . . . . . . . . . 13 14. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14 15. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 14 16. References . . . . . . . . . . . . . . . . . . . . . . . . . 14 16.1. Normative References . . . . . . . . . . . . . . . . . . 14 16.2. Informative References . . . . . . . . . . . . . . . . . 15 Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 18 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18 Tse & Wong Expires March 2, 2018 [Page 2]

Internet-Draft August 2017 1. Introduction SM2 [SM2] [I-D.shen-sm2-ecdsa], SM3 [SM3] [I-D.shen-sm3-hash] and SM4 [SM4] are cryptographic standards issued by the Organization of State Commercial Administration of China [OSCCA] as authorized cryptographic algorithms for the use within China. These algorithms are published in public. Adoption of this document enables exchange of OpenPGP-secured email [RFC4880] in a OSCCA-compliant manner through usage of the authorized combination of SM2, SM3 and SM4. SM2 [SM2] [I-D.shen-sm2-ecdsa] is a set of public key cryptographic algorithms based on elliptic curves that include: o Digital Signature Algorithm [SM2-2] o Key Exchange Protocol [SM2-3] o Public Key Encryption Algorithm [SM2-4] SM3 [SM3] [I-D.shen-sm3-hash] is a hash algorithm designed for electronic authentication purposes. SM4 [SM4] is a symmetric encryption algorithm designed for data encryption. This document extends OpenPGP [RFC4880] and its ECC extension [RFC6637] to support SM2, SM3 and SM4: o support the SM3 hash algorithm for data validation purposes o support signatures utilizing the combination of SM3 with other digital signing algorithms, such as RSA and SM2 o support the SM2 asymmetric encryption algorithm for public key operations o support usage of SM2 in combination with supported hash algorithms, such as SHA-256 and SM4 o support the SM4 symmetric encryption algorithm for data protection purposes o defines the OpenPGP "OSCCA-compliant profile" to enable usage of OpenPGP in an OSCCA-compliant manner. Tse & Wong Expires March 2, 2018 [Page 3]

Internet-Draft August 2017 2. 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]. Compliant applications are a subset of the broader set of OpenPGP applications described in [RFC4880]. Any [RFC2119] keyword within this document applies to compliant applications only. 2.1. Definitions OSCCA-compliant All algorithms used for encryption and signatures are compliant with OSCCA regulations. SM2DSA The elliptic curve digital signature algorithm defined in [SM2-2] and [I-D.shen-sm2-ecdsa] SM2KEP The elliptic curve key exchange protocol defined in [SM2-3] SM2PKE The public key encryption algorithm defined in [SM2-4] 3. SM2 ECC Algorithms SM2 is an elliptic curve based cryptosystem (ECC) [SM2] designed by Xiaoyun Wang et al and published by [OSCCA] [I-D.shen-sm2-ecdsa]. The SM2 cryptosystem is composed of three distinct algorithms: o an elliptical curve digital signature algorithm ("SM2DSA") [SM2-2], also described in [I-D.shen-sm2-ecdsa]; o a key exchange protocol ("SM2KEP") [SM2-3]; and o a public key encryption algorithm ("SM2PKE") [SM2-4]. This document will refer to all three algorithms for the usage of OpenPGP [RFC4880]. 3.1. SM2 Digital Signature Algorithm The SM2 Digital Signature Algorithm is intended for digital signature and verifications in commercial cryptographic applications, including, but not limited to: Tse & Wong Expires March 2, 2018 [Page 4]

Internet-Draft August 2017 o identity authentication o protection of data integrity o verification of data authenticity The process of digital signature signing and verifying along with their examples are found in [SM2-2], and also described in [I-D.shen-sm2-ecdsa]. In OpenPGP, SM2DSA is an alternative to the ECDSA algorithm specified in [RFC6637]. The SM2DSA algorithm has been cryptanalyzed to a certain extent, with the current strongest attack being nonce [SM2-DSA-Nonces] [SM2-DSA-Nonces2] and lattice attacks [SM2-DSA-Lattice]. 3.2. SM2 Key Exchange Protocol The SM2 Key Exchange Protocol is used for cryptographic key exchange, allowing the negoatiation and exchange of a session key within two to three message transfers. The process of key exchange and verification along with their examples are found in [SM2-3], and also described in [I-D.shen-sm2-ecdsa]. SM2KEP is not used with OpenPGP as it is a two- to three- pass key exchange mechanism, while in OpenPGP public keys of recipients are available initially. The SM2KEP is now considered insecure due to [SM2-KEP-Comments], similar in status to the Unified Model and MQV schemes described in [NIST.SP.800-56Ar2]. 3.3. SM2 Public Key Encryption The SM2 Public Key Encryption algorithm is an elliptic curve (ECC) based asymmetric encryption algorithm. It is used for cryptographic encryption and decryption, allowing the message sender to utilize the public key of the message receiver to encrypt the message, with the recipient decrypting the messaging using his private key. The full description of SM2PKE is provided in [I-D.shen-sm2-ecdsa]. It utilizes a public key size of 512 bits and private key size of 256 bits [GMT-0003.1-2012]. Tse & Wong Expires March 2, 2018 [Page 5]

Internet-Draft August 2017 The process of encryption and decryption, along with their examples are found in [SM2-4]. In OpenPGP, SM2PKE is an alternative to RSA specified in [RFC4880]. 3.4. Recommended SM2 Curve The recommended curve is specified in [SM2-5] and provided here for reference. SM2 uses a 256-bit elliptic curve. 3.4.1. Definitions p a number larger than 3 a, b elements of F_q, defines an elliptic curve E on F_q n Order of base point G (n is a prime factor of E(F_q)) x_G x-coordinate of generator G y_G y-coordinate of generator G 3.4.2. Elliptic Curve Formula y^2 = x^3 + ax + b 3.4.3. Curve Parameters p = FFFFFFFE FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF 00000000 FFFFFFFF FFFFFFFF a = FFFFFFFE FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF 00000000 FFFFFFFF FFFFFFFC b = 28E9FA9E 9D9F5E34 4D5A9E4B CF6509A7 F39789F5 15AB8F92 DDBCBD41 4D940E93 n = FFFFFFFE FFFFFFFF FFFFFFFF FFFFFFFF 7203DF6B 21C6052B 53BBF409 39D54123 x_G = 32C4AE2C 1F198119 5F990446 6A39C994 8FE30BBF F2660BE1 715A4589 334C74C7 y_G = BC3736A2 F4F6779C 59BDCEE3 6B692153 D0A9877C C62A4740 02DF32E5 2139F0A0 Tse & Wong Expires March 2, 2018 [Page 6]

Internet-Draft August 2017 4. SM3 Hash Algorithm The SM3 Cryptographic Hash Algorithm [SM3] is an iterated hash function designed by Xiaoyun Wang et al., published by [OSCCA] as an alternative to SHA-2 [NIST.FIPS.180-4]. The algorithm is designed to be used for various commercial cryptographic applications including, but not limited to: o digital signatures and their verification o message authentication code generation and their verification o generation of random numbers According to the authors, SM3 is designed with a Merkle-Damgard construction and is very similar to SHA-2 [NIST.FIPS.180-4] of the MD4 [RFC6150] family, with the addition of several strengthening features such as a more complex step function and stronger message dependency than SHA-256 [SM3-Boomerang]. SM3 produces an output hash value of 256 bits long, based on 512-bit input message blocks [SM3-Boomerang], on input lengths up to 2^(m). The specification of SM3 is described in [SM3] and [I-D.shen-sm3-hash]. 5. SM4 Symmetric Encryption Algorithm SM4 [SM4] is a symmetric encryption algorithm designed by Shuwang Lu et al. in 2006 as SMS4, and officially published published by the OSCCA in 2012 as SM4. The algorithm is publicly described in "GM/T 0002-2012 SM4 Block Cipher Algorithm Standard" [SM4], and is used in WAPI (Wired Authentication and Privacy Infrastructure), the Chinese National Standard for Wireless LAN [GB15629.11-2003]. SM4 is a 128-bit block cipher, uses a key size of 128 bits and internally uses an 8-bit S-box. It performs 32 rounds per block, and decryption simply reverses the order of encryption. 6. Supported Algorithms Tse & Wong Expires March 2, 2018 [Page 7]

Internet-Draft August 2017 6.1. Public Key Algorithms The SM2 algorithm is supported with the following extension. The following public key algorithm IDs are added to expand Section 9.1 of [RFC4880], "Public-Key Algorithms": +-----+--------------------------+ | ID | Description of Algorithm | +-----+--------------------------+ | TBD | SM2 | +-----+--------------------------+ Compliant applications MUST support both usages of SM2: o SM2 Digital Signature Algorithm (SM2DSA) [SM2-2] [I-D.shen-sm2-ecdsa] o SM2 Public Key Encryption (SM2PKE) [SM2-4] [I-D.shen-sm2-ecdsa] 6.2. Symmetric Key Algorithms The SM4 algorithm is supported with the following extension. The following symmetric encryption algorithm ID is added to expand Section 9.2 of [RFC4880], "Symmetric-Key Algorithms": +-----+--------------------------+ | ID | Description of Algorithm | +-----+--------------------------+ | TBD | SM4 | +-----+--------------------------+ Compliant applications MUST support SM4. 6.3. Hash Algorithms The SM3 algorithm is supported with the following extension. The following symmetric encryption algorithm IDs are added to expand Section 9.3 of [RFC4880], "Hash Algorithms": +-----+--------------------------+ | ID | Description of Algorithm | +-----+--------------------------+ | TBD | SM3 | +-----+--------------------------+ Tse & Wong Expires March 2, 2018 [Page 8]

Internet-Draft August 2017 Compliant applications MUST support SM3. 7. Conversion Primitives The encoding method of [RFC6637] Section 6 MUST be used, and is compatible with the definition given in [SEC1]. For clarity, according to the EC curve MPI encoding method of [RFC6637], the exact size of the MPI payload for the "SM2 Recommended" 256-bit curve, is 515 bits. 8. SM2 Key Derivation Function A key derivation function (KDF) is necessary to implement EC encryption. The SM2PKE KDF is defined in Section 5.4.3 of [I-D.shen-sm2-ecdsa] (originally from Section 3.4.3 of [SM2-4]) and SHOULD be used in conjunction with an OSCCA-approved hash algorithm, such as SM3 [SM3]. The pseudocode is provided here for convenience. 8.1. Prerequisites o H_v() is a hash function that outputs a v-bit long hash value. 8.2. Inputs o Bit stream "Z" o Length of output key "klen" (an integer less than (2^32 - 1) x v). 8.3. Output o Key "K" of length "klen" 8.4. Pseudocode Tse & Wong Expires March 2, 2018 [Page 9]

Internet-Draft August 2017 KDF (Z, klen) { Counter = 0x00000001 [a 32-bit register] n = klen / v Iterate from i = 1 to Ceil(n) Ha[i] = H_v( Z || Counter ) Counter++ If n is a whole number Ha![Ceil(n)] = Ha[Ceil(n)] Else Ha![Ceil(n)] = leftmost (klen - (v x Floor(n))) bits of Ha[Ceil(n)] K = Ha[1] || Ha[2] || ... || Ha[Ceil(n)-1] || Ha![Ceil(n)] } 9. Encoding of Public and Private Keys 9.1. Public-Key Packet Formats The following algorithm-specific packets are added to Section 5.5.2 of [RFC4880], "Public-Key Packet Formats", to support SM2DSA and SM2PKE. This document extends the algorithm-specific portion with the following fields. Algorithm-Specific Fields for SM2DSA keys: o a variable-length field containing a curve OID, formatted as follows: * a one-octet size of the following field; values 0 and 0xFF are reserved for future extensions * octets representing a curve OID, described in Section 11 o MPI of an EC point representing a public key Algorithm-Specific Fields for SM2PKE keys: o a variable-length field containing a curve OID, formatted as follows: * a one-octet size of the following field; values 0 and 0xFF are reserved for future extensions * octets representing a curve OID, described in Section 11 Tse & Wong Expires March 2, 2018 [Page 10]

Internet-Draft August 2017 o MPI of an EC point representing a public key o a variable-length field containing KDF parameters, formatted as follows: * a one-octet size of the following fields; values 0 and 0xff are reserved for future extensions * a one-octet value 01, reserved for future extensions * a one-octet hash function ID used with a KDF An SM2PKE public key is composed of the same sequence of fields that define an SM2DSA key, plus the KDF parameters field. 9.2. Secret-Key Packet Formats The following algorithm-specific packets are added to Section 5.5.3. of [RFC4880], "Secret-Key Packet Formats", to support SM2DSA and SM2PKE. This document extends the algorithm-specific portion with the following fields. Algorithm-Specific Fields for SM2DSA or SM2PKE secret keys: o an MPI of an integer representing the secret key, which is a scalar of the public EC point 10. Message Encoding with Public Keys 10.1. Public-Key Encrypted Session Key Packets (Tag 1) Section 5.1 of [RFC4880], "Public-Key Encrypted Session Key Packets (Tag 1)" is extended to support SM2PKE using the following algorithm specific fields for SM2PKE, through applying the KDF described in Section 8. Algorithm Specific Fields for SM2 encryption: o MPI of SM2 encrypted value "C = (C1 || C2 || C3)", described in step A2 of Section 7.2.1. of [I-D.shen-sm2-ecdsa] o A one-octet number giving the hash algorithm used for the calculation of "C3", described in step A7 of Section 7.2.1. of [I-D.shen-sm2-ecdsa]. Tse & Wong Expires March 2, 2018 [Page 11]

Internet-Draft August 2017 10.2. Signature Packet (Tag 2) 10.2.1. Version 3 Signature Packet Format Section 5.2.2 of [RFC4880] define the signature format for "Version 3 Signature Packet Format". Similar to ECDSA [RFC6637], no changes in the format is necessary for SM2DSA. 10.2.2. Version 4 Signature Packet Format Section 5.2.3 of [RFC4880] define the signature format for "Version 4 Signature Packet Format". Similar to ECDSA [RFC6637], no changes in the format is necessary for SM2DSA. 11. SM2 ECC Curve OID This section provides the "SM2 Recommended Curve" described in [SM2-5] according to the method of [RFC6637]. The named curves are referenced as a sequence of bytes in this document, called throughout, curve OID. Section 11 describes in detail how this sequence of bytes is formed. The parameter curve OID is an array of octets that define a named curve. The table below specifies the exact sequence of bytes for each named curve referenced in this document: +---------------------+-------+-----------------------+-------------+ | ASN.1 Object | OID | Curve OID bytes in | Curve name | | Identifier | len | hexadecimal | | | | | representation | | +---------------------+-------+-----------------------+-------------+ | 1.2.156.10197.1.301 | 8 | 2A 81 1C CF 55 01 82 | SM2 | | | | 2D | Recommended | +---------------------+-------+-----------------------+-------------+ The sequence of octets in the third column is the result of applying the Distinguished Encoding Rules (DER) to the ASN.1 Object Identifier with subsequent truncation. The truncation removes the two fields of encoded Object Identifier. The first omitted field is one octet representing the Object Identifier tag, and the second omitted field is the length of the Object Identifier body. The complete ASN.1 DER encoding for the SM2 Recommended curve OID is "06 08 2A 81 1C CF 55 01 82 2D", from which the first entry in the table above is constructed by omitting the first two octets. Only the truncated sequence of octets is the valid representation of a curve OID. Tse & Wong Expires March 2, 2018 [Page 12]

Internet-Draft August 2017 12. Compatibility Profiles 12.1. OSCCA Compliant Profile A compliant application MUST implement: o SM2 Recommended Curve o SM2 (SM2DSA and SM2PKE) o SM3 o SM4 13. Security Considerations o Products and services that utilize cryptography are regulated by OSCCA [OSCCA]; they must be explicitly approved or certified by OSCCA before being allowed to be sold or used in China. o SM2 [SM2] is an elliptic curve cryptosystem (ECC) published by OSCCA [OSCCA]. Its security relies on the assumption that the elliptic curve discrete logarithm problem (ECLP) is computationally infeasible. With advances in cryptanalysis, new attack algorithms may reduce the complexity of ECLP, making it easier to attack the SM2 cryptosystem that is considered secure at the time this document is published. You SHOULD check current literature to determine if the algorithms in SM2 have been found vulnerable. o SM3 [SM3] is a cryptographic hash algorithm published by OSCCA [OSCCA]. No formal proof of security is provided. As claimed in [I-D.shen-sm3-hash], the security properties of SM3 are under public study. There are no known feasible attacks against the SM3 algorithm at the time this document is published. o SM4 [SM4] is a block cipher certified by OSCCA [OSCCA]. No formal proof of security is provided. There are no known feasible attacks against SM4 algorithm by the time of publishing this document. On the other hand, there are security concerns with regards to side-channel attacks, when the SM4 algorithm is implemented in a device [SM4-Power]. For instance, [SM4-Power] illustrated an attack by measuring the power consumption of the device. A chosen ciphertext attack, assuming a fixed correlation between the sub-keys and data mask, is able to recover the round key successfully. When the SM4 algorithm is implemented in hardware, the parameters/keys SHOULD be randomly generated without fixed correlation. Tse & Wong Expires March 2, 2018 [Page 13]

Internet-Draft August 2017 o SM2 has a key length of 512 bits for public key and 256 bits for private key. It is considered an alternative to ECDSA P-256 [RFC6637]. Its security strength is comparable to a 128-bit symmetric key strength [I-D.ietf-msec-mikey-ecc], e.g., AES-128 [NIST.FIPS.197]. o SM3 is a hash function that generates a 256-bit hash value. It is considered as an alternative to SHA-256. o SM4 is a block cipher symmetric algorithm with key length of 128 bits. It is considered as an alternative to AES-128 [NIST.FIPS.197]. o Security considerations offered in [RFC6637] and [RFC4880] also apply. 14. IANA Considerations The IANA "Pretty Good Privacy (PGP)" registry [RFC8126] has made the following assignments for algorithms described in this document, namely: o ID XXX of the "Public Key Algorithms" namespace for Section 3 o ID XXX of the "Hash Algorithms" namespace for Section 4 o ID XXX of the "Symmetric Key Algorithms" namespace for Section 5 15. Examples TODO! 16. References 16.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, <https://www.rfc- editor.org/info/rfc2119>. [RFC4880] Callas, J., Donnerhacke, L., Finney, H., Shaw, D., and R. Thayer, "OpenPGP Message Format", RFC 4880, DOI 10.17487/RFC4880, November 2007, <https://www.rfc- editor.org/info/rfc4880>. Tse & Wong Expires March 2, 2018 [Page 14]

Internet-Draft August 2017 [RFC6637] Jivsov, A., "Elliptic Curve Cryptography (ECC) in OpenPGP", RFC 6637, DOI 10.17487/RFC6637, June 2012, <https://www.rfc-editor.org/info/rfc6637>. [SM2] Organization of State Commercial Administration of China, "Public Key Cryptographic Algorithm SM2 Based on Elliptic Curves", December 2010, <http://www.oscca.gov.cn/UpFile/2010122214822692.pdf>. [SM2-2] Organization of State Commercial Administration of China, "Public Key Cryptographic Algorithm SM2 Based on Elliptic Curves -- Part 2: Digital Signature Algorithm", December 2010, <http://www.oscca.gov.cn/UpFile/2010122214822692.pdf>. [SM2-4] Organization of State Commercial Administration of China, "Public Key Cryptographic Algorithm SM2 Based on Elliptic Curves -- Part 4: Public Key Encryption Algorithm", December 2010, <http://www.oscca.gov.cn/UpFile/2010122214822692.pdf>. [SM2-5] Organization of State Commercial Administration of China, "Public Key Cryptographic Algorithm SM2 Based on Elliptic Curves -- Part 5: Parameter definitions", December 2010, <http://www.oscca.gov.cn/UpFile/2010122214836668.pdf>. [SM3] Organization of State Commercial Administration of China, "SM3 Cryptographic Hash Algorithm", December 2010, <http://www.oscca.gov.cn/UpFile/20101222141857786.pdf>. [SM4] Organization of State Commercial Administration of China, "SM4 block cipher algorithm", December 2010, <http://www.oscca.gov.cn/UpFile/200621016423197990.pdf>. 16.2. Informative References [GB15629.11-2003] Standardization Administration of the People's Republic of China, "Information technology -- Telecommunications and information exchange between systems -- Local and metropolitan area networks -- Specific requirements -- Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications", May 2003, <http://www.gb688.cn/bzgk/gb/ newGbInfo?hcno=74B9DD11287E72408C19C4D3A360D1BD>. Tse & Wong Expires March 2, 2018 [Page 15]

Internet-Draft August 2017 [GMT-0003.1-2012] Organization of State Commercial Administration of China, "GM/T 0003.1-2012: Public Key Cryptographic Algorithm SM2 Based on Elliptic Curves Part 1: General", March 2012, <http://www.oscca.gov.cn/Column/Column_32.htm>. [I-D.ietf-msec-mikey-ecc] Milne, A., "ECC Algorithms for MIKEY", draft-ietf-msec- mikey-ecc-03 (work in progress), June 2007. [I-D.shen-sm2-ecdsa] Shen, S., Shen, S., and X. Lee, "SM2 Digital Signature Algorithm", draft-shen-sm2-ecdsa-02 (work in progress), February 2014. [I-D.shen-sm3-hash] Shen, S. and S. Shen, "SM3 Hash function", draft-shen- sm3-hash-01 (work in progress), February 2014. [NIST.FIPS.180-4] National Institute of Standards and Technology, "FIPS 180-4 Secure Hash Standard (SHS)", August 2015, <http://dx.doi.org/10.6028/NIST.FIPS.180-4>. [NIST.FIPS.197] National Institute of Standards and Technology, "FIPS 197 Advanced Encryption Standard (AES)", November 2001, <https://doi.org/10.6028/NIST.FIPS.197>. [NIST.SP.800-56Ar2] Barker, B., Chen, L., Roginsky, A., and M. Smid, "SP 800-56Ar2 Recommendation for Pair-Wise Key Establishment Schemes Using Discrete Logarithm Cryptography", May 2013, <http://dx.doi.org/10.6028/NIST.SP.800-56Ar2>. [OSCCA] Organization of State Commercial Administration of China, "Organization of State Commercial Administration of China", May 2017, <http://www.oscca.gov.cn>. [RFC6150] Turner, S. and L. Chen, "MD4 to Historic Status", RFC 6150, DOI 10.17487/RFC6150, March 2011, <https://www.rfc-editor.org/info/rfc6150>. [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 8126, DOI 10.17487/RFC8126, June 2017, <https://www.rfc-editor.org/info/rfc8126>. Tse & Wong Expires March 2, 2018 [Page 16]

Internet-Draft August 2017 [SEC1] Standards for Efficient Cryptography Group, "SEC 1: Elliptic Curve Cryptography", September 2010, <http://www.secg.org/SEC1-Ver-1.0.pdf>. [SM2-3] Organization of State Commercial Administration of China, "Public Key Cryptographic Algorithm SM2 Based on Elliptic Curves -- Part 3: Key Exchange Protocol", December 2010, <http://www.oscca.gov.cn/UpFile/2010122214822692.pdf>. [SM2-DSA-Lattice] Cao, W., Feng, J., Zhu, S., Chen, H., Wu, W., Han, X., and X. Zheng, "Practical Lattice-Based Fault Attack and Countermeasure on SM2 Signature Algorithm", November 2016, <https://doi.org/10.1007/978-3-319-29814-6_6>. [SM2-DSA-Nonces] Liu, M., Chen, J., and H. Li, "Partially Known Nonces and Fault Injection Attacks on SM2 Signature Algorithm", November 2013, <https://dx.doi.org/10.1007/978-3-319-12087-4_22>. [SM2-DSA-Nonces2] Chen, J., Liu, M., Shi, H., and H. Li, "Mind Your Nonces Moving: Template-Based Partially-Sharing Nonces Attack on SM2 Digital Signature Algorithm", November 2015, <https://doi.acm.org/10.1145/2714576.2714587>. [SM2-KEP-Comments] Xu, X. and D. Feng, "Comments on the SM2 Key Exchange Protocol", December 2011, <https://dx.doi.org/10.1007/978-3-642-25513-7_12>. [SM3-Boomerang] Bai, D., Yu, H., Wang, G., and X. Wang, "Improved Boomerang Attacks on Round-Reduced SM3 and Keyed Permutation of BLAKE-256", April 2015, <https://doi.org/10.1049/iet-ifs.2013.0380>. [SM4-Power] Du, Z., Wu, Z., Wang, M., and J. Rao, "Improved chosen- plaintext power analysis attack against SM4 at the round- output", October 2015, <http://dx.doi.org/10.6028/NIST.FIPS.180-4>. Tse & Wong Expires March 2, 2018 [Page 17]

Internet-Draft August 2017 Appendix A. Acknowledgements The authors would like to thank the following persons for their valuable advice and input. o Jack Lloyd and Daniel Wyatt of the Ribose rnp team for their input and implementation Authors' Addresses Ronald Henry Tse Ribose Suite 1111, 1 Pedder Street Central, Hong Kong Hong Kong Email: ronald.tse@ribose.com URI: https://www.ribose.com Dr. Wai Kit Wong Hang Seng Management College Hang Shin Link, Siu Lek Yuen Shatin, New Territories Hong Kong Email: wongwk@hsmc.edu.hk URI: https://www.hsmc.edu.hk Tse & Wong Expires March 2, 2018 [Page 18]