@0xpolygonid/js-sdk
Version:
SDK to work with Polygon ID
89 lines (88 loc) • 3.12 kB
JavaScript
import { Hex, PrivateKey, PublicKey, Signature } from '@iden3/js-crypto';
import { BytesHelper, checkBigIntInField } from '@iden3/js-iden3-core';
import { KmsKeyType } from '../store';
import * as providerHelpers from '../provider-helpers';
import { hexToBytes } from '../../utils';
/**
* Provider for Baby Jub Jub keys
* @public
* @class BjjProvider
* @implements implements IKeyProvider interface
*/
export class BjjProvider {
/**
* Creates an instance of BjjProvider.
* @param {KmsKeyType} keyType - kms key type
* @param {AbstractPrivateKeyStore} keyStore - key store for kms
*/
constructor(keyType, keyStore) {
if (keyType !== KmsKeyType.BabyJubJub) {
throw new Error('Key type must be BabyJubJub');
}
this.keyType = keyType;
this.keyStore = keyStore;
}
/**
* get all keys
* @returns list of keys
*/
async list() {
const allKeysFromKeyStore = await this.keyStore.list();
return allKeysFromKeyStore.filter((key) => key.alias.startsWith(this.keyType));
}
/**
* generates a baby jub jub key from a seed phrase
* @param {Uint8Array} seed - byte array seed
* @returns kms key identifier
*/
async newPrivateKeyFromSeed(seed) {
const newKey = new Uint8Array(32);
newKey.set(Uint8Array.from(seed), 0);
newKey.fill(seed.length, 32, 0);
const privateKey = new PrivateKey(seed);
const publicKey = privateKey.public();
const kmsId = {
type: this.keyType,
id: providerHelpers.keyPath(this.keyType, publicKey.hex())
};
await this.keyStore.importKey({ alias: kmsId.id, key: privateKey.hex() });
return kmsId;
}
/**
* Gets public key by kmsKeyId
*
* @param {KmsKeyId} keyId - key identifier
*/
async publicKey(keyId) {
const privateKey = await this.privateKey(keyId);
return privateKey.public().hex();
}
/**
* signs prepared payload of size,
* with a key id
*
* @param {KmsKeyId} keyId - key identifier
* @param {Uint8Array} data - data to sign (32 bytes)
* @returns Uint8Array signature
*/
async sign(keyId, data) {
if (data.length != 32) {
throw new Error('data to sign is too large');
}
const i = BytesHelper.bytesToInt(data);
if (!checkBigIntInField(i)) {
throw new Error('data to sign is too large');
}
const privateKey = await this.privateKey(keyId);
const signature = privateKey.signPoseidon(i);
return signature.compress();
}
async privateKey(keyId) {
const privateKeyHex = await this.keyStore.get({ alias: keyId.id });
return new PrivateKey(Hex.decodeString(privateKeyHex));
}
async verify(message, signatureHex, keyId) {
const publicKey = await this.publicKey(keyId);
return PublicKey.newFromCompressed(hexToBytes(publicKey)).verifyPoseidon(BytesHelper.bytesToInt(message), Signature.newFromCompressed(hexToBytes(signatureHex)));
}
}