TBD B. Fussell, Ed.
Internet-Draft Cisco Systems, Inc.
Intended status: Informational June 1, 2016
Expires: December 3, 2016

ACVP ECDSA Algorithm JSON Specification
draft-ietf-acvp-subecdsa-1.0

Abstract

This document defines the JSON schema for using ECDSA algorithms with the ACVP specification.

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/.

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This Internet-Draft will expire on December 3, 2016.

Copyright Notice

Copyright (c) 2016 IETF Trust and the persons identified as the document authors. All rights reserved.

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Table of Contents

1. Introduction

The Automated Crypto Validation Protocol (ACVP) defines a mechanism to automatically verify the cryptographic implementation of a software or hardware crypto module. The ACVP specification defines how a crypto module communicates with an ACVP server, including crypto capabilities negotiation, session management, authentication, vector processing and more. The ACVP specification does not define algorithm specific JSON constructs for performing the crypto validation. A series of ACVP sub-specifications define the constructs for testing individual crypto algorithms. Each sub-specification addresses a specific class of crypto algorithms. This sub-specification defines the JSON constructs for testing ECDSA algorithms using ACVP.

1.1. Requirements Language

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted in RFC 2119.

2. Supported ECDSA Algorithms

The following ECDSA algorithms MAY be advertised by the ACVP compliant cryptographic module:

3. Test Types and Test Coverage

The ACVP server performs a set of tests on the specified ECDSA algorithm in order to assess the correctness and robustness of the implementation. A typical ACVP validation session SHALL require multiple tests to be performed for every supported permutation of ECDSA capabilities. This section describes the design of the tests used to validate implementations of the ECDSA algorithms.

3.1. Test Coverage

The tests described in this document have the intention of ensuring an implementation is conformant to [FIPS.186-4] and [SP.800-89].

3.1.1. Requirements Covered

3.1.2. Requirements Not Covered

4. Capabilities Registration

ACVP requires crypto modules to register their capabilities. This allows the crypto module to advertise support for specific algorithms, notifying the ACVP server which algorithms need test vectors generated for the validation process. This section describes the constructs for advertising support of ECDSA algorithms to the ACVP server.

The algorithm capabilities are advertised as JSON objects within the 'algorithms' value of the ACVP registration message. The 'algorithms' value is an array, where each array element is an individual JSON object defined in this section. The 'algorithms' value is part of the 'capability_exchange' element of the ACVP JSON registration message. See the ACVP specification for details on the registration message.

4.1. Required Prerequisite Algorithms for ECDSA Validations

Each ECDSA implementation relies on other cryptographic primitives. For example, ECDSA uses an underlying SHA algorithm. Each of these underlying algorithm primitives must be validated, either separately or as part of the same submission. ACVP provides a mechanism for specifying the required prerequisites:

Required ECDSA Prerequisite Algorithms JSON Values
JSON Value Description JSON type Valid Values Optional
algorithm a prerequisite algorithm value DRBG, DRBG_OPT2, SHA, SHA_OPT2, SHA_OPT3 No
valValue algorithm validation number value actual number or "same" No
prereqAlgVal prerequistie algorithm validation object with algorithm and valValue properties see above No
prereqVals prerequistie algorithm validations array of prereqAlgVal objects see above No

4.2. ECDSA Algorithm Capabilities Registration

Each algorithm capability advertised is a self-contained JSON object using the following values

ECDSA Algorithm Capabilities JSON Values
JSON Value Description JSON type Valid Values Optional
algorithm The algorithm under test value "ECDSA" No
mode The ECDSA mode to be validated value "keyGen", "keyVer", "sigGen", or "sigVer" No
revision The algorithm testing revision to use. value "1.0" No
prereqVals prerequistie algorithm validations array of prereqAlgVal objects See Section 4.1 No
capabilities array of JSON objects, each with fields pertaining to the global ECDSA mode indicated above and identified uniquely by the combination of the ECDSA "mode" and indicated properties Array of JSON objects See Section 4.3 Yes
conformances Used to denote the conformances that can apply to specific modes of DSA. Array of strings See Section 5 Yes

4.3. Supported ECDSA Modes Capabilities

The ECDSA mode capabilities are advertised as JSON objects within the 'capabilities' value of the ACVP registration message - see Table 2 . The 'capabilities' value is an array, where each array element is a JSON object corresponding to a particular ECDSA mode defined in this section. The 'capabilities' value is part of the 'capability_exchange' element of the ACVP JSON registration message. See the ACVP specification for details on the registration message.

Each ECDSA mode's capabilities are advertised as JSON objects.

4.3.1. The keyGen Mode Capabilities

The ECDSA keyGen mode capabilities are advertised as JSON objects, which are elements of the 'capabilities' array in the ACVP registration message. See the ACVP specification for details on the registration message.

Each ECDSA keyGen mode capability set is advertised as a self-contained JSON object.

4.3.1.1. keyGen Full Set of Capabilities

The complete list of ECDSA key generation capabilities may be advertised by the ACVP compliant crypto module:

ECDSA keyGen Capabilities JSON Values
JSON Value Description JSON type Valid Values Optional
curve The curve names supported for the IUT in keyGen. array Any non-empty subset of {"P-224", "P-256", "P-384", "P-521", "B-233", "B-283", "B-409", "B-571", "K-233", "K-283", "K-409", "K-571"} No
secretGenerationMode The method used to generate the randomness incoporated in the key. array Any non-empty subset of {"extra bits", "testing candidates"} No

4.3.2. The keyVer Mode Capabilities

The ECDSA keyVer mode capabilities are advertised as JSON objects, which are elements of the 'capabilities' array in the ACVP registration message. See the ACVP specification for details on the registration message.

Each ECDSA keyVer mode capability set is advertised as a self-contained JSON object.

4.3.2.1. keyVer Full Set of Capabilities

The complete list of ECDSA key verification capabilities may be advertised by the ACVP compliant crypto module:

ECDSA keyVer Capabilities JSON Values
JSON Value Description JSON type Valid Values Optional
curve The curve names supported for the IUT in keyVer. array Any non-empty subset of {"P-192", "P-224", "P-256", "P-384", "P-521", "B-163", "B-233", "B-283", "B-409", "B-571", "K-163", "K-233", "K-283", "K-409", "K-571"} No

4.3.3. The sigGen Mode Capabilities

The ECDSA sigGen mode capabilities are advertised as JSON objects, which are elements of the 'capabilities' array in the ACVP registration message. See the ACVP specification for details on the registration message.

Each ECDSA sigGen mode capability set is advertised as a self-contained JSON object.

4.3.3.1. sigGen Full Set of Capabilities

The complete list of ECDSA signature generation capabilities may be advertised by the ACVP compliant crypto module:

ECDSA sigGen Capabilities JSON Values
JSON Value Description JSON type Valid Values Optional
capabilities An array containing capability objects defined as an array of 'curve' and an array of 'hashAlg' as listed below. array Any non-empty subset of capability objects No
curve The curves supported with a particular set of hash algorithms. array Any non-empty subset of {"P-224", "P-256", "P-384", "P-521", "B-233", "B-283", "B-409", "B-571", "K-233", "K-283", "K-409", "K-571"} No
hashAlg The hash functions supported when signing a message for a particular set of curves. array Any non-empty subset of {"SHA2-224", "SHA2-256", "SHA2-384", "SHA2-512", "SHA2-512/224", "SHA2-512/256"}. No

4.3.4. The sigVer Mode Capabilities

The ECDSA sigVer mode capabilities are advertised as JSON objects, which are elements of the 'capabilities' array in the ACVP registration message. See the ACVP specification for details on the registration message.

Each ECDSA sigVer mode capability set is advertised as a self-contained JSON object.

4.3.4.1. sigVer Full Set of Capabilities

The complete list of ECDSA signature verification capabilities may be advertised by the ACVP compliant crypto module:

ECDSA sigVer Capabilities JSON Values
JSON Value Description JSON type Valid Values Optional
capabilities An array containing capability objects defined as an array of 'curve' and an array of 'hashAlg' as listed below. array Any non-empty subset of capability objects No
curve The curves supported with a particular set of hash algorithms. array Any non-empty subset of {"P-192", "P-224", "P-256", "P-384", "P-521", "B-163", "B-233", "B-283", "B-409", "B-571", "K-163", "K-233", "K-283", "K-409", "K-571"} No
hashAlg The hash functions supported when signing a message for a particular set of curves. array Any non-empty subset of {"SHA-1", "SHA2-224", "SHA2-256", "SHA2-384", "SHA2-512", "SHA2-512/224", "SHA2-512/256"}. No

5. Supported DSA Conformances

Conformances MAY be used to test additional features of certain algorithms.

DSA Conformances
String Value Description Valid algorithm modes Optional
SP800-106 This conformance signifies the SigGen and/or SigVer modes support randomized message hashing as described in [SP.800-106]. Utilizing this conformance SHALL generate additional test groups, denoted with a group level property of `"conformance": "SP800-106"`. SigGen, SigVer Yes

6. Test Vectors

The ACVP server provides test vectors to the ACVP client, which are then processed and returned to the ACVP server for validation. A typical ACVP validation session would require multiple test vector sets to be downloaded and processed by the ACVP client. Each test vector set represents an individual ECDSA function. This section describes the JSON schema for a test vector set used with ECDSA algorithms.

The test vector set JSON schema is a multi-level hierarchy that contains meta data for the entire vector set as well as individual test vectors to be processed by the ACVP client.The following table describes the JSON elements at the top level of the hierarchy.

Vector Set JSON Object
JSON Value Description JSON type
acvVersion Protocol version identifier value
vsId Unique numeric identifier for the vector set value
algorithm ECDSA value
mode The ECDSA mode used for the test vectors value
revision The algorithm testing revision to use. value
testGroups Array of test group JSON objects, which are defined in Section 6.1 array

6.1. Test Groups JSON Schema

The testGroups element at the top level in the test vector JSON object is an array of test groups. Test vectors are grouped into similar test cases to reduce the amount of data transmitted in the vector set. For instance, all test vectors that use the same key size would be grouped together. The Test Group JSON object contains meta data that applies to all test vectors within the group. The following table describes the secure hash JSON elements of the Test Group JSON object.

The test group for ECDSA is as follows:

Vector Group JSON Object
JSON Value Description JSON type Optional
curve The curve type used for the test vectors. value No
secretGenerationMode The method of generating a secret used for key generation in the test vectors. value Yes
hashAlg SHA version used value Yes
qx The public key curve point x value Yes
qy The public key curve point y value Yes
conformance Signifies all test cases within the group should utilize random message hashing as described in [SP.800-106]. "SP800-106" Yes
tests Array of individual test vector JSON objects, which are defined in Section 6.2 array No

6.2. Test Case JSON Schema

Each test group contains an array of one or more test cases. Each test case is a JSON object that represents a single test vector to be processed by the ACVP client. The following table describes the JSON elements for each ECDSA test vector.

Test Case JSON Object
JSON Value Description JSON type Optional
tcId Numeric identifier for the test case, unique across the entire vector set. value No
qx The public key curve point x value Yes
qy The public key curve point y value Yes
r The signature component R value Yes
s The signature component S value Yes
message The message used to generate signature or verify signature value Yes
randomValue The random value to be used as an input into the message randomization function as described in [SP.800-106]. value Yes
randomValueLen The random value's bit length. value Yes

7. Test Vector Responses

After the ACVP client downloads and processes a vector set, it must send the response vectors back to the ACVP server. The following table describes the JSON object that represents a vector set response.

Vector Set Response JSON Object
JSON Value Description JSON type
acvVersion Protocol version identifier value
vsId Unique numeric identifier for the vector set value
testResults Array of JSON objects that represent each test vector result, as defined by the tables below array

The following table describes the JSON object that represents a vector set response for ECDSA.

Vector Set Response JSON Object
JSON Value Description JSON type Optional
d The private key value Yes
qx The public key curve point x value Yes
qy The public key curve point y value Yes
r The signature component R value Yes
s The signature component S value Yes
randomValue The random value to be used as an input into the message randomization function as described in [SP.800-106]. value Yes
randomValueLen The random value's bit length. value Yes
testPassed The Pass or Fail result of the verify or validation boolean Yes

8. Acknowledgements

TBD...

9. IANA Considerations

This memo includes no request to IANA.

10. Security Considerations

Security considerations are addressed by the ACVP specification.

11. Normative References

[ACVP] authSurName, authInitials., "ACVP Specification", 2016.
[FIPS.186-4] NIST, "Digital Signature Standard (DSS)", July 2013.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997.
[SP.800-106] NIST, "Randomized Hashing for Digital Signatures", February 2009.
[SP.800-89] NIST, "Recommendation for Obtaining Assurances for Digital Signature Applications", July 2013.

Appendix A. Example Capabilities JSON Object

The following sections contain example JSON for the various ECDSA modes: keyGen, keyVer, sigGen, and sigVer. Note that all binary HEX representations are in big-endian format.

                        
[{
		"algorithm": "ECDSA",
		"mode": "keyGen",
		"revision": "1.0",
		"prereqVals": [{
				"algorithm": "SHA",
				"valValue": "123456"
			},
			{
				"algorithm": "DRBG",
				"valValue": "123456"
			}
		],
		"curve": [
			"P-224",
			"P-256",
			"P-384",
			"P-521",
			"B-233",
			"B-283",
			"B-409",
			"B-571",
			"K-233",
			"K-283",
			"K-409",
			"K-571"
		],
		"secretGenerationMode": [
			"extra bits",
			"testing candidates"
		]
	},
	{
		"algorithm": "ECDSA",
		"mode": "keyVer",
		"revision": "1.0",
		"prereqVals": [{
				"algorithm": "SHA",
				"valValue": "123456"
			},
			{
				"algorithm": "DRBG",
				"valValue": "123456"
			}
		],
		"curve": [
			"P-192",
			"P-224",
			"P-256",
			"P-384",
			"P-521",
			"B-163",
			"B-233",
			"B-283",
			"B-409",
			"B-571",
			"K-163",
			"K-233",
			"K-283",
			"K-409",
			"K-571"
		]
	},
	{
		"algorithm": "ECDSA",
		"mode": "sigGen",
		"revision": "1.0",
		"prereqVals": [{
				"algorithm": "SHA",
				"valValue": "123456"
			},
			{
				"algorithm": "DRBG",
				"valValue": "123456"
			}
		],
		"capabilities": [{
			"curve": [
				"P-224",
				"P-256",
				"P-384",
				"P-521",
				"B-233",
				"B-283",
				"B-409",
				"B-571",
				"K-233",
				"K-283",
				"K-409",
				"K-571"
			],
			"hashAlg": [
				"SHA2-224",
				"SHA2-256",
				"SHA2-384",
				"SHA2-512",
				"SHA2-512/224",
				"SHA2-512/256"
			]
		}],
		"conformances": [
			"SP800-106"
		]
	},
	{
		"algorithm": "ECDSA",
		"mode": "sigVer",
		"revision": "1.0",
		"prereqVals": [{
				"algorithm": "SHA",
				"valValue": "123456"
			},
			{
				"algorithm": "DRBG",
				"valValue": "123456"
			}
		],
		"capabilities": [{
			"curve": [
				"P-192",
				"P-224",
				"P-256",
				"P-384",
				"P-521",
				"B-163",
				"B-233",
				"B-283",
				"B-409",
				"B-571",
				"K-163",
				"K-233",
				"K-283",
				"K-409",
				"K-571"
			],
			"hashAlg": [
				"SHA-1",
				"SHA2-224",
				"SHA2-256",
				"SHA2-384",
				"SHA2-512",
				"SHA2-512/224",
				"SHA2-512/256"
			]
		}],
		"conformances": [
			"SP800-106"
		]
	}
]
            
                    

Appendix B. Example Vector Set Request/Responses JSON Object

B.1. Example Test ECDSA KeyGen JSON Object

The following is a example JSON object for ECDSA KeyGen, test vectors sent from the ACVP server to the crypto module and the response.

                        
[
    {
        "acvVersion": <acvp-version>
    },
    {
        "vsId": 1564,
        "algorithm": "ECDSA",
        "mode": "keyGen",
        "revision": "1.0",
        "testGroups": [
            {
				"tgId": 1,
                "curve": "P-224",
                "secretGenerationMode": "extra bits",
                "tests": [
                    {
                        "tcId": 1
                    }
                ]
            }
        ]
    }
]
            
                    

The following is a example JSON object for ECDSA KeyGen test results sent from the crypto module to the ACVP server.

                        
[
    {
        "acvVersion": <acvp-version>
    },
    {
        "vsId": 1564,
        "testGroups": [
            {
				"tgId": 1,
				"tests": [
					{
						"tcId": 1,
						"qx": "7B1AA6BE712542282B8D088C233168CA4409E20264E32897C201ABA9",
						"qy": "BCC9213347A7F988A2FF9EF14C85254B23AF0096F947CECB6C3311D2",
						"d": "38524F26660BBA72E74EB39DEF38558EB07CB15255A09652B222CCE0"
					}
				]
            }
        ]
    }
]
            
                    

B.2. Example Test ECDSA KeyVer JSON Object

The following is a example JSON object for ECDSA KeyVer, test vectors sent from the ACVP server to the crypto module and the response.

                        
[
    {
        "acvVersion": <acvp-version>
    },
    {
        "vsId": 1564,
        "algorithm": "ECDSA",
        "mode": "keyVer",
        "revision": "1.0",
        "testGroups": [
            {
				"tgId": 1,
                "curve": "P-192",
                "tests": [
                    {
                        "tcId": 1,
                        "qx": "01ED77E3F1591D2EC730D0ED6D592F8DD24158D0E696408DBD",
                        "qy": "BF31C6463EB1B6B55C8930550B88CF8D1F6432A832B40FB4"
                    }
                ]
            }
        ]
    }
]
            
                    

The following is a example JSON object for ECDSA KeyVer test results sent from the crypto module to the ACVP server.

                        
[
    {
        "acvVersion": <acvp-version>
    },
    {
        "vsId": 1564,
        "testGroups": [
            {
				"tgId": 1,
				"tests": [
					{
					    "tcId": 1,
                		"testPassed": false
					}
				]
            }
        ]
    }
]
            
                    

B.3. Example Test ECDSA Signature Generation JSON Object

The following is a example JSON object for ECDSA SigGen, test vectors sent from the ACVP server to the crypto module and the response.

                        
[
    {
        "acvVersion": <acvp-version>
    },
    {
        "vsId": 1564,
        "algorithm": "ECDSA",
        "mode": "sigGen",
        "revision": "1.0",
        "testGroups": [
            {
                "tgId": 1,
                "curve": "P-224",
                "hashAlg": "SHA2-224",
                "tests": [
                    {
                        "tcId": 1,
                        "message": "AB6F57713A3BD323B4AFDCFBE202EE00A9CF5C787D19FD9094323C57FEA8B7FBE31559EC1CAC6D29C3229A58811CF2BAE2B78183DFDABD055B741EA86496454F085D17D5BCD1B82B533B533A1E5804B2DAA0ED43F8BF59FBEB16BDD4D7C065165CB9B085CECD5BCFFA794339D5A81B1949F569CAACA208B9E3E6A217A1B3A596"
                    }
                ]
            },
            {
                "tgId": 2,
                "curve": "P-224",
                "hashAlg": "SHA2-224",
                "conformance": "SP800-106",
                "tests": [
                    {
                        "tcId": 2,
                        "message": "23B4AFDCFBE202EE00A9CF5C787D19FD90..."
                    }
                ]
            }
        ]
    }
]
            
                    

The following is a example JSON object for ECDSA SigGen test results sent from the crypto module to the ACVP server.

                        
[
    {
        "acvVersion": <acvp-version>
    },
    {
        "vsId": 1564,
        "testGroups": [
            {
                "tgId": 1,
                "qx": "3B1D9E4D986F651C3C213B2A1304693BDB8BA632CB93A3547B89EF31",
                "qy": "E56F7B7C9E6355E573B7B3B6C0E1ECD70E4ABDF1554EAD8A68ABA1A4",
                "tests": [
                    {
                        "tcId": 1,
                        "r": "3E2A9588DF3D3F11B16368A30C8C34C572655BA8516AF5C914E94FF4",
                        "s": "C6E4A8C51E0A0E11C4C6D6F8F3C51A0FA440BC6FF28EBACDBB20922A"
                    }
                ]
            },
            {
                "tgId": 2,
                "qx": "A1304693BDBA632CB93A3B8BA632CB93A3...",
                "qy": "ECD70E4ABBA632CB93A3BA632CB93A3DF1...",
                "tests": [
                    {
                        "tcId": 2,
                        "r": "3E2A9588DF3D3F11B16368A30C8C34C572655BA8516AF5C914E94FF4",
                        "s": "C6E4A8C51E0A0E11C4C6D6F8F3C51A0FA440BC6FF28EBACDBB20922A",
                        "randomValue": "0A0E11C4C6D6F8F3C51..."
                        "randomValueLen": 1024
                    }
                ]
            }
        ]
    }
]
          
                    

B.4. Example Test ECDSA SigVer JSON Object

The following is a example JSON object for ECDSA SigVer, test vectors sent from the ACVP server to the crypto module and the response.

                        
[
    {
        "acvVersion": <acvp-version>
    },
    {
        "vsId": 1564,
        "algorithm": "ECDSA",
        "mode": "sigVer",
        "revision": "1.0",
        "testGroups": [
            {
                "tgId": 1,
                "curve": "P-192",
                "hashAlg": "SHA-1",
                "tests": [
                    {
                        "tcId": 1,
                        "message": "D38A81D0C5201BA4A06A8C4760AC15DB266B17B48B13EA69775D1E896486D9D986A464D3469941F93FC65556E2CB8AB5F113E7ADCB8D50375DC76907195B6AF6C06F13EB6106EF0E19E241DB4B4831E06437E5CF7C9A499A8FC6DA36A75BDB81A2A19E14ACEFECD7E364471527E0FE37FD1162F5DD0D975E83C0DA4EDDD37261",
                        "qx": "B08AFEAC74E42C66EBAF13807E2EB5769F5123645C0B8491",
                        "qy": "55847857E5E48025BE9053952E0E1ECFB1D883CF9F085386",
                        "r": "E31121E544D476DC3FA79B4DCB0A7252B6E80468BBF22843",
                        "s": "6E3F47F2327E36AD936E0F4BE245C05F264BA9300E9E7DD9"
                    }
                ]
            },
            {
                "tgId": 2,
                "curve": "P-192",
                "hashAlg": "SHA-1",
                "conformance": "SP800-106",
                "tests": [
                    {
                        "tcId": 2,
                        "message": "D38A81D04A06A8C4760AC15DB266B17B48B...",
                        "randomValue": "1527E0FE37FD1162F5DD0D975E83C0D...",
                        "randomValueLen": 1024
                        "qx": "D1E896486D9D986A464D3469941F93FC65556E2CB...",
                        "qy": "ADCB8D50375DC76907195B6AF6C06F...",
                        "r": "6D9D986A464D3469941F93FC65556E2CB8AB5F113...",
                        "s": "8E713EB6106EF0E19E241DB4B4831E06437E5C..."
                    }
                ]
            }
        ]
    }
]
            
                    

The following is a example JSON object for ECDSA generation test results sent from the crypto module to the ACVP server.

                        
[
    {
        "acvVersion": <acvp-version>
    },
    {
        "vsId": 1564,
        "testGroups": [
            {
                "tgId": 1,
                "tests": [
                    {
                        "tcId": 1,
                        "testPassed": false
                    }
                ],
                "tgId": 2,
                "tests" [
                    {
                        "tcId": 2,
                        "testPassed": true
                    }
                ]
            }
        ]
    }
]
          
                    

Author's Address

Barry Fussell (editor) Cisco Systems, Inc. 170 West Tasman Dr. San Jose, CA 95134 USA EMail: bfussell@cisco.com