Node.js keyObject.equals() Method

The keyObject.equals() of the crypto module in Node.js, which allows you to compare two key objects. By default, this method returns a boolean indicating whether the keyObject passed is equal to the key object the method is applied to. This method makes decisions based on the key’s type, value, and parameters.

Syntax: 

keyObject.equals(KeyObject);

Return Value: This method returns a boolean indicating whether the keyObject passed is equal to the key object the method is applied to.

We will now see some examples of keyObject.equals(otherKeyObject) method.

Example 1: Let’s create one more keyObject with the same Algorithm and attributes and compares the above one and this newly created keyObject using the keyObject.equals() method.

Javascript

// Importing the crypto module
const {
    webcrypto: { subtle }, KeyObject
} = require('node:crypto');

(async function () {

    //  Crypto Key Instance
    const k1 = await subtle.generateKey({

        // Algorithm name
        name: 'AES-CBC',

        // Length of key in bits.
        length: 192,
    },
        // Not exportable.
        false,

        // Key can be used in encryption
        // and decryption
        ['encrypt', 'decrypt']);

    // Creating KeyObject-1
    const keyObject1 = KeyObject.from(k1);

    // Creating KeyObject-2 using same key Instance
    const keyObject2 = KeyObject.from(k1);

    // Comparing both KeyObjects:
    result = keyObject1.equals(keyObject2);

    // Printing the result
    console.log(result);

})();

Output: In the example above, two key objects were created using the same cryptographic key instance. Then I applied keyObject.equals() method to check if the two key objects are equal or not. The result is true because both the keyObjects are generated using the same crypto key instance. All the parameters and values are the same for both key Objects.

true

Example 2: Let’s create one more keyObject with different attributes and values. Compare both the keyObject.

Javascript

// Importing the crypto module
const {
    webcrypto: { subtle }, KeyObject
} = require('node:crypto');

(async function () {

    //  Crypto Key Instance
    const k1 = await subtle.generateKey({

        // Algorithm name
        name: 'AES-CBC',

        // Length of key in bits.
        length: 192,
    },
        // Not exportable.
        false,

        // Key can be used in encryption
        // and decryption
        ['encrypt', 'decrypt']);

    const k2 = await subtle.generateKey(
        {
            name: "HMAC",
            hash: "SHA-256",
            length: 256,
        },
        true,
        ["sign", "verify"]
    );


    // Creating KeyObject-1:
    const keyObject1 = KeyObject.from(k1);

    // Creating KeyObject-2 using same key Instance:
    const keyObject2 = KeyObject.from(k2);

    // Comparing both KeyObjects:
    result = keyObject1.equals(keyObject2);

    // Printing the result
    console.log(result);

})();

Output: In the above example, we have created two different key objects using two different crypto key Instances. We have used the AES algorithm to generate the first crypto key instance and the HMAC algorithm to generate the second key Instance. All the parameters and values are different for both the key objects so this method returns false.

false

Reference: https://nodejs.org/api/crypto.html#keyobjectequalsotherkeyobject