What is Node.js tlsSocket.getEphemeralKeyInfo() Method?

In this article, we will learn Node.js tlsSocket.getEphemeralKeyInfo() Method,This free Node.js tutorial for complete beginners will help you learn Node.js from scratch.

Node.js tlsSocket.getEphemeralKeyInfo() Method️‍🔥

The tlsSocket.getEphemeralKeyInfo() is an inbuilt application programming interface of class TLSSocket within tls module which is used to return an object containing information of ephemeral key exchange.

Syntax:

const tlsSocket.getEphemeralKeyInfo()

Parameters: This method does not accept any parameter.

Return Value: This method returns an object containing information of ephemeral key exchange.

How to generate a private key and public certificate?

Private key: Open Notepad and copy and paste the following key:

Save the file as a private key.pem

Public certificate: Open Notepad and copy and paste the following key:

Save the file as public-cert.pem

Example 1: Filename: index.js

javascript

// Node.js program to demonstrate the
// tlsSocket.getEphemeralKeyInfo() method
 
const tls = require('tls'),
    fs = require('fs'),
 
    // Port and host address for server
    PORT = 1337,
    HOST = '127.0.0.1',
    value = null;
 
// Private key and public certificate for access
const options = {
    key: fs.readFileSync('private-key.pem'),
    cert: fs.readFileSync('public-cert.pem'),
    rejectUnauthorized: false
};
 
// Creating and initializing server
const server = tls.createServer(options,
    function (socket) {
 
        // Print the data that we received
        socket.on('data', function (data) {
            console.log('\nReceived: %s ',
                data.toString().replace(/(\n)/gm, ""));
        });
 
        // Stopping the server
        // by using the close() method
        server.close(() => {
            console.log("Server closed successfully");
        });
    });
 
// Start listening on a specific port and address
// by using listen() method
server.listen(PORT, HOST, function () {
    console.log("I'm listening at %s, "
        + "on port %s", HOST, PORT);
});
 
// Creating and initializing client
const client = tls.connect(PORT,
    HOST, options, function () {
 
        // Getting object containing information
        // regarding EphemeralKey by using
        // tlsSocket.getEphemeralKeyInfo() method
        value = client.getEphemeralKeyInfo();
 
        client.write("EphemeralKey : " + value.name);
 
        client.end(() => {
            console.log("Client closed successfully");
        });
    });

Run the index.js file using the following command:

node index.js

Output:

I'm listening at 127.0.0.1, on port 1337
Client closed successfully

Received: EphemeralKey : X25519
Server closed successfully

Example 2: Filename: index.js

javascript

// Node.js program to demonstrate the
// tlsSocket.getEphemeralKeyInfo() API
const tls = require('tls'),
    fs = require('fs'),
 
    // Port and host address for server
    PORT = 1337,
    HOST = '127.0.0.1';
 
// Private key and public certificate for access
const options = {
    key: fs.readFileSync('private-key.pem'),
    cert: fs.readFileSync('public-cert.pem'),
    rejectUnauthorized: false
};
 
// Creating and initializing server
const server = tls.createServer(options,
    function (socket) {
 
        // Getting object containing information
        // regarding EphemeralKey by using
        // tlsSocket.getEphemeralKeyInfo() method
        value = socket.getEphemeralKeyInfo();
 
        socket.write("EphemeralKey : " + value);
 
        // Stopping the server
        // by using the close() method
        server.close(() => {
            console.log("Server closed successfully")
        });
    });
 
// Start listening on a specific port
// and address by using listen() method
server.listen(PORT, HOST, function () {
    console.log("I'm listening at %s, "
        + "on port %s", HOST, PORT);
});
 
// Creating and initializing client
const client = tls.connect(PORT,
    HOST, options, function () {
        console.log("client is connected");
    });
 
client.on("data", function (data) {
 
    console.log('Received: %s',
        data.toString().replace(/(\n)/gm, ""));
 
    // Close the connection after
    // receiving the message
    client.end(() => {
        console.log("client closed successfully")
    });
});

Run the index.js file using the following command:

node index.js

Output:

I'm listening at 127.0.0.1, on port 1337
client is connected
Received: EphemeralKey : null
client closed successfully
Server closed successfully

Reference: https://nodejs.org/dist/latest-v12.x/docs/api/tls.html#tls_tlssocket_getephemeralkeyinfo