Node.js – diffieHellman.getGenerator() Method

The diffieHellman.getGenerator() method returns the Diffie-Hellman generator in the specified encoding. A string is returned in case an encoding is passed, else a buffer is returned.

Syntax

diffieHellman.getGenerator([encoding])

Parameters

• encoding - This parameter specifies the encoding of the return value.

Example 1

Create a file with the name "generator.js" and copy the following code. After creating the file, use the command "node generator.js" to run this code as shown in the example below:

// diffieHellman.getPrime() Demo Example

// Importing cryptoDiffieHellman from the crypto module
const { createDiffieHellman } = require('crypto');

// Initializing the diffieHellman object
const dh = createDiffieHellman(512);

// Generate DiffieHellman's Generator

// Defining generator
let dhGenerator = dh.getGenerator()
console.log('Buffer (when encoding is not specified) : ', dhGenerator)

// Encoding specified
// Return String
dhGenerator = dh.getGenerator('base64')
console.log('String (when encoding is specified) : ', dhGenerator)

Output

Buffer (when encoding is not specified) : <Buffer 02>
String (when encoding is specified) : Ag==

Example 2

Let's take a look at one more example.

// diffieHellman.getGenerator() Demo Example

// Importing cryptoDiffieHellman from the crypto module
const { createDiffieHellman } = require('crypto');

// Generating keys for 'a'
const a = createDiffieHellman(512);

// Generating prime for 'a'
const primeA = a.getPrime();

// Generating a's generator
const generatorA = a.getGenerator()

// Generating a's generatorKeys
const keyA = a.generateKeys();

// Generating keys for b
const b = createDiffieHellman( primeA, generatorA );

// Generating prime for b
const primeB = b.getPrime();

// Generating b's generator
const generatorB = b.getGenerator()

// Generating b's generatorKeys
const keyB = b.generateKeys();

// Exchanging the secret
const secretA = a.computeSecret(keyB);
const secretB = b.computeSecret(keyA);

let isSymmetric =
   secretA.toString('hex') == secretB.toString('hex')
console.log('Are keys Symmetric : ${ isSymmetric }')

Output

Are keys Symmetric : ${ isSymmetric }