src/ECPrivateKey.js
import * as asn1js from "asn1js";
import { getParametersValue, toBase64, arrayBufferToString, stringToArrayBuffer, fromBase64, clearProps } from "pvutils";
import ECPublicKey from "./ECPublicKey.js";
//**************************************************************************************
/**
* Class from RFC5915
*/
export default class ECPrivateKey
{
//**********************************************************************************
/**
* Constructor for ECCPrivateKey class
* @param {Object} [parameters={}]
* @property {Object} [schema] asn1js parsed value
*/
constructor(parameters = {})
{
//region Internal properties of the object
/**
* @type {number}
* @description version
*/
this.version = getParametersValue(parameters, "version", ECPrivateKey.defaultValues("version"));
/**
* @type {OctetString}
* @description privateKey
*/
this.privateKey = getParametersValue(parameters, "privateKey", ECPrivateKey.defaultValues("privateKey"));
if("namedCurve" in parameters)
/**
* @type {string}
* @description namedCurve
*/
this.namedCurve = getParametersValue(parameters, "namedCurve", ECPrivateKey.defaultValues("namedCurve"));
if("publicKey" in parameters)
/**
* @type {ECPublicKey}
* @description publicKey
*/
this.publicKey = getParametersValue(parameters, "publicKey", ECPrivateKey.defaultValues("publicKey"));
//endregion
//region If input argument array contains "schema" for this object
if("schema" in parameters)
this.fromSchema(parameters.schema);
//endregion
//region If input argument array contains "json" for this object
if("json" in parameters)
this.fromJSON(parameters.json);
//endregion
}
//**********************************************************************************
/**
* Return default values for all class members
* @param {string} memberName String name for a class member
*/
static defaultValues(memberName)
{
switch(memberName)
{
case "version":
return 1;
case "privateKey":
return new asn1js.OctetString();
case "namedCurve":
return "";
case "publicKey":
return new ECPublicKey();
default:
throw new Error(`Invalid member name for ECCPrivateKey class: ${memberName}`);
}
}
//**********************************************************************************
/**
* Compare values with default values for all class members
* @param {string} memberName String name for a class member
* @param {*} memberValue Value to compare with default value
*/
static compareWithDefault(memberName, memberValue)
{
switch(memberName)
{
case "version":
return (memberValue === ECPrivateKey.defaultValues(memberName));
case "privateKey":
return (memberValue.isEqual(ECPrivateKey.defaultValues(memberName)));
case "namedCurve":
return (memberValue === "");
case "publicKey":
return ((ECPublicKey.compareWithDefault("namedCurve", memberValue.namedCurve)) &&
(ECPublicKey.compareWithDefault("x", memberValue.x)) &&
(ECPublicKey.compareWithDefault("y", memberValue.y)));
default:
throw new Error(`Invalid member name for ECCPrivateKey class: ${memberName}`);
}
}
//**********************************************************************************
/**
* Return value of asn1js schema for current class
* @param {Object} parameters Input parameters for the schema
* @returns {Object} asn1js schema object
*/
static schema(parameters = {})
{
// ECPrivateKey ::= SEQUENCE {
// version INTEGER { ecPrivkeyVer1(1) } (ecPrivkeyVer1),
// privateKey OCTET STRING,
// parameters [0] ECParameters {{ NamedCurve }} OPTIONAL,
// publicKey [1] BIT STRING OPTIONAL
// }
/**
* @type {Object}
* @property {string} [blockName]
* @property {string} [version]
* @property {string} [privateKey]
* @property {string} [namedCurve]
* @property {string} [publicKey]
*/
const names = getParametersValue(parameters, "names", {});
return (new asn1js.Sequence({
name: (names.blockName || ""),
value: [
new asn1js.Integer({ name: (names.version || "") }),
new asn1js.OctetString({ name: (names.privateKey || "") }),
new asn1js.Constructed({
optional: true,
idBlock: {
tagClass: 3, // CONTEXT-SPECIFIC
tagNumber: 0 // [0]
},
value: [
new asn1js.ObjectIdentifier({ name: (names.namedCurve || "") })
]
}),
new asn1js.Constructed({
optional: true,
idBlock: {
tagClass: 3, // CONTEXT-SPECIFIC
tagNumber: 1 // [1]
},
value: [
new asn1js.BitString({ name: (names.publicKey || "") })
]
})
]
}));
}
//**********************************************************************************
/**
* Convert parsed asn1js object into current class
* @param {!Object} schema
*/
fromSchema(schema)
{
//region Clear input data first
clearProps(schema, [
"version",
"privateKey",
"namedCurve",
"publicKey"
]);
//endregion
//region Check the schema is valid
const asn1 = asn1js.compareSchema(schema,
schema,
ECPrivateKey.schema({
names: {
version: "version",
privateKey: "privateKey",
namedCurve: "namedCurve",
publicKey: "publicKey"
}
})
);
if(asn1.verified === false)
throw new Error("Object's schema was not verified against input data for ECPrivateKey");
//endregion
//region Get internal properties from parsed schema
this.version = asn1.result.version.valueBlock.valueDec;
this.privateKey = asn1.result.privateKey;
if("namedCurve" in asn1.result)
this.namedCurve = asn1.result.namedCurve.valueBlock.toString();
if("publicKey" in asn1.result)
{
const publicKeyData = { schema: asn1.result.publicKey.valueBlock.valueHex };
if("namedCurve" in this)
publicKeyData.namedCurve = this.namedCurve;
this.publicKey = new ECPublicKey(publicKeyData);
}
//endregion
}
//**********************************************************************************
/**
* Convert current object to asn1js object and set correct values
* @returns {Object} asn1js object
*/
toSchema()
{
const outputArray = [
new asn1js.Integer({ value: this.version }),
this.privateKey
];
if("namedCurve" in this)
{
outputArray.push(new asn1js.Constructed({
idBlock: {
tagClass: 3, // CONTEXT-SPECIFIC
tagNumber: 0 // [0]
},
value: [
new asn1js.ObjectIdentifier({ value: this.namedCurve })
]
}));
}
if("publicKey" in this)
{
outputArray.push(new asn1js.Constructed({
idBlock: {
tagClass: 3, // CONTEXT-SPECIFIC
tagNumber: 1 // [1]
},
value: [
new asn1js.BitString({ valueHex: this.publicKey.toSchema().toBER(false) })
]
}));
}
return new asn1js.Sequence({
value: outputArray
});
}
//**********************************************************************************
/**
* Convertion for the class to JSON object
* @returns {Object}
*/
toJSON()
{
if((("namedCurve" in this) === false) || (ECPrivateKey.compareWithDefault("namedCurve", this.namedCurve)))
throw new Error("Not enough information for making JSON: absent \"namedCurve\" value");
let crvName = "";
switch(this.namedCurve)
{
case "1.2.840.10045.3.1.7": // P-256
crvName = "P-256";
break;
case "1.3.132.0.34": // P-384
crvName = "P-384";
break;
case "1.3.132.0.35": // P-521
crvName = "P-521";
break;
default:
}
const privateKeyJSON = {
crv: crvName,
d: toBase64(arrayBufferToString(this.privateKey.valueBlock.valueHex), true, true, false)
};
if("publicKey" in this)
{
const publicKeyJSON = this.publicKey.toJSON();
privateKeyJSON.x = publicKeyJSON.x;
privateKeyJSON.y = publicKeyJSON.y;
}
return privateKeyJSON;
}
//**********************************************************************************
/**
* Convert JSON value into current object
* @param {Object} json
*/
fromJSON(json)
{
let coodinateLength = 0;
if("crv" in json)
{
switch(json.crv.toUpperCase())
{
case "P-256":
this.namedCurve = "1.2.840.10045.3.1.7";
coodinateLength = 32;
break;
case "P-384":
this.namedCurve = "1.3.132.0.34";
coodinateLength = 48;
break;
case "P-521":
this.namedCurve = "1.3.132.0.35";
coodinateLength = 66;
break;
default:
}
}
else
throw new Error("Absent mandatory parameter \"crv\"");
if("d" in json)
{
const convertBuffer = stringToArrayBuffer(fromBase64(json.d, true));
if(convertBuffer.byteLength < coodinateLength)
{
const buffer = new ArrayBuffer(coodinateLength);
const view = new Uint8Array(buffer);
const convertBufferView = new Uint8Array(convertBuffer);
view.set(convertBufferView, 1);
this.privateKey = new asn1js.OctetString({ valueHex: buffer });
}
else
this.privateKey = new asn1js.OctetString({ valueHex: convertBuffer.slice(0, coodinateLength) });
}
else
throw new Error("Absent mandatory parameter \"d\"");
if(("x" in json) && ("y" in json))
this.publicKey = new ECPublicKey({ json });
}
//**********************************************************************************
}
//**************************************************************************************
