Dashmachine crypto utility library

Cryptographic helper functions for use in Dash Platform Web Dapp Sample Messaging.

Note: this is an experimental library to support the web dapp sample investigation of Dash Platform usage - not for production use.

Breaking Changes From v1.0.0 DashJS is required as an external dependency in both browser and node.js versions

Prerequisites

To utilise the encryption & decryption by username The library requires DashJS as an external dependency, so this must be referenced BEFORE the Dashmachine Crypto library. In Node.js:

const Dash = require('dash');
const DashmachineCrypto = require('dashmachine-crypto');

In the browser:

<script src="https://unpkg.com/dash"></script>
<script src="dashmachine-crypto-lib.js" type="text/javascript"></script>

Please see the examples below for sample usage

Browser usage

Include the dashmachine-crypto-lib.js script file available from the releases page.

Nodejs usage

npm i dashmachine-crypto

Documentation

Table of Contents

• DashmachineCrypto
  • Examples
• encrypt
  • Parameters
• decrypt
  • Parameters
• hash
  • Parameters
• verify
  • Parameters
• generateEntropy
• encryptForUsername
  • Parameters
• decryptForUsername
  • Parameters

DashmachineCrypto

DashmachineCrypto performs ECIES encryption & decryption and Double SHA256 Hashing. Note the class contains only static methods so you do not have to call the contructor, i.e. use DashmachineCrypto.encrypt, not new DashmachineCrypto()

Examples

<!-- Usage in HTML file -->
<script src="https://unpkg.com/dash"></script>
<script src="dashmachine-crypto-lib.js" type="text/javascript"></script>
<script>
const vendorPrivateKey = '40148175614f062fb0b4e5c519be7b6f57b872ebb55ea719376322fd12547bff'
const message = 'hello';
const userPublicKey = 'A7GGInyvn7ExXkSVg+OFhbhVjEMhIFv0oyeJl03gFDRo'
const userPrivateKey = '219c8a8f9376750cee9f06e0409718f2a1b88df4acc61bf9ed9cf252c8602768'
const vendorPublicKey = 'A0/qSE6tis4l6BtQlTXB2PHW+WV+Iy0rpF5hAvX8hDRz'
console.log(`Encrypting message "${message}"...`);
const encrypted = DashmachineCrypto.encrypt(vendorPrivateKey, message, userPublicKey);
console.dir(encrypted.data);
console.log(`Decrypting result message "${message}"...`);
const decrypted = DashmachineCrypto.decrypt(userPrivateKey, encrypted.data, vendorPublicKey);
console.dir(decrypted);
console.log(`Hashing message "${message}"...`);
const digest = DashmachineCrypto.hash(message);
console.dir(digest.data);
console.log(`Verifying hash...`);
const verifies = DashmachineCrypto.verify(message, digest.data);
console.dir(verifies.success)
const entropy = DashmachineCrypto.generateEntropy();
console.log(`entropy: ${entropy}`);

const senderName = 'alice';
const senderMnemonic = 'uniform analyst paper father soldier toe lesson fetch exhaust jazz swim response';
const recipientName = 'bob';
const recipientMnemonic = 'liar fee island situate deal exotic flat direct save bag fiscal news';
const userMessage = `Hello ${recipientName}!`;
const dpnsContractId = '295xRRRMGYyAruG39XdAibaU9jMAzxhknkkAxFE7uVkW'

async function testUsernameEncryption() {
try {
console.log(`send message \"${userMessage}\" to user: ${recipientName}`)
const encrypted = await DashmachineCrypto.encryptForUsername(userMessage, senderName, recipientName, senderMnemonic, dpnsContractId);
console.log('encrypted:', encrypted.data);
const decrypted = await DashmachineCrypto.decryptForUsername(encrypted.data, recipientName, senderName, recipientMnemonic, dpnsContractId)
console.log('decrypted:', decrypted.data);
}
catch (e) {
console.log('error :', e);

}

}

(async () => { await testUsernameEncryption() })()
</script>

//use in nodejs
const Dash = require('dash');
const DashmachineCrypto = require("dashmachine-crypto")

const vendorPrivateKey = '40148175614f062fb0b4e5c519be7b6f57b872ebb55ea719376322fd12547bff'
const message = 'hello';
const userPublicKey = 'A7GGInyvn7ExXkSVg+OFhbhVjEMhIFv0oyeJl03gFDRo'
const userPrivateKey = '219c8a8f9376750cee9f06e0409718f2a1b88df4acc61bf9ed9cf252c8602768'
const vendorPublicKey = 'A0/qSE6tis4l6BtQlTXB2PHW+WV+Iy0rpF5hAvX8hDRz'
console.log(`Encrypting message "${message}"...`);
const encrypted = DashmachineCrypto.encrypt(vendorPrivateKey, message, userPublicKey);
console.dir(encrypted.data);
console.log(`Decrypting result message "${message}"...`);
const decrypted = DashmachineCrypto.decrypt(userPrivateKey, encrypted.data, vendorPublicKey);
console.dir(decrypted);
console.log('decrypted', decrypted.data);
const entropy = DashmachineCrypto.generateEntropy();
console.log(`entropy: ${entropy}`);

const senderName = 'alice';
const senderMnemonic = 'uniform analyst paper father soldier toe lesson fetch exhaust jazz swim response';
const recipientName = 'bob';
const recipientMnemonic = 'liar fee island situate deal exotic flat direct save bag fiscal news';
const userMessage = `Hello ${recipientName}!`;
const dpnsContractId = '295xRRRMGYyAruG39XdAibaU9jMAzxhknkkAxFE7uVkW'

async function testUsernameEncryption() {
try {
console.log(`send message \"${userMessage}\" to user: ${recipientName}`)
const encrypted = await DashmachineCrypto.encryptForUsername(userMessage, senderName, recipientName, senderMnemonic, dpnsContractId);
console.log('encrypted:', encrypted.data);
const decrypted = await DashmachineCrypto.decryptForUsername(encrypted.data, recipientName, senderName, recipientMnemonic, dpnsContractId)
console.log('decrypted:', decrypted.data);
}
catch (e) {
console.log('error :', e);

}

}

(async () => { await testUsernameEncryption() })()

encrypt

Parameters

• senderPrivateKey string The base64 repesentation of the HD private key of the Dash User sending the message, the result of calling client.account.getIdentityHDKey(0, 'user').privateKey where client is an instance of Dash.Client
• message string message to encrypt
• recipientPublicKey object The base64 repesentation of the public key for the Identity of the Dash User receiveing the message

Returns Object Either {success: true, data: [encrypted message]} or {error: true, message: [error message]}

decrypt

Parameters

• recipientPrivateKey string The base64 repesentation of the HD private key of the Dash User receiving the message, the result of calling client.account.getIdentityHDKey(0, 'user').privateKey where client is an instance of Dash.Client
• encryptedMessage string message to decrypt as a hex representation of the stringified JSON of the encryption result buffer
• senderPublicKey object The base64 repesentation of the public key for the Identity of the Dash User sending the message

Returns Object Either {success: true, data: [decrypted message]} or {error: true, message: [error message]}

hash

Parameters

• message string full message to be hashed

Returns Object Either {success: true, data: [digest]} or {error: true, message: [error message]}

verify

Parameters

• message string full message to be hashed
• digest string digest to compare

generateEntropy

Returns Object Either {success: true, data: [generated entropy]} or {error: true, message: [error message]}

encryptForUsername

Parameters

• message string The message to encrypt
• senderName string DPNS username of sender
• recipientName string DPNS username of recipient
• senderMnemonic string Account mnemonic of sender
• dpnsContractId string contractId for DPNS contract

Returns Object {success: true, data: encryptedMessage} | {Error}

decryptForUsername

Parameters

• message string The message to decrypt
• recipientName string DPNS username of recipient
• senderName string DPNS username of sender
• recipientMnemonic string Account mnemonic of recipient
• dpnsContractId string contractId for DPNS contract

Returns Object {success: true, data: encryptedMessage} or {Error}

License

MIT License

Development

To develop this library:

• clone the repository and change to project directory

  git clone https://github.com/dashmachine/dashmachine-crypto.git && cd dashmachine-crypto

The source file is src/crypto.service.js

• build output

  npm run build

• test with webpack dev server

  npm start

• update documentation (requires npm documentation package installed globally: npm i -g documentation)

Update the Documentation section of the README.md file

npm run docs:readme