Password Verification in Node.js

In Node for password hashing and verification we can use a npm library known as bcryptjs npm-bcryptjs.

Installation of bcryptjs: Node.js contains an inbuilt crypto module’s randomBytes interface which is used to obtain the secure random numbers.

npm install bcryptjs

Approach:

• To hash a password use bcrypt.hash(plainTextPassword, salt, callback) which returns a promise if no callback is passed.
• To verify plain text password with hashed password use bcrypt.compare(plainTextPassword, hashedPassword, callback) which also returns a promise if no callback is passed.

Example 1:

// Use bcryptjs module
const bcrypt = require("bcryptjs");

// Store the password into variable
const password = "password123";

// Use bcrypt.hash() function to hash the password
bcrypt.hash(password, 8, (err, hashedPassword) => {
    if (err) {
        return err;
    }

    // Display the hashed password
    console.log(hashedPassword);

    // Use bcrypt.compare() function to compare
    // the password with hashed password
    bcrypt.compare(password, hashedPassword, (err, isMatch) => {
        if( err ) {
            return err;
        }

        // If password matches then display true
        console.log(isMatch);
    });
});

Output:

$2a$08$PV4rYpBwXUPAGuMedxUnAOxq/TozK9o/QSUWaKE1XL8psOyZ.JL4q
true

Example 2:

// Use bcryptjs module
const bcrypt = require("bcryptjs");

// Store the password into variable
const password = "password123";

// Use bcrypt.hash() function to hash the password
bcrypt.hash(password, 8).then(hashedPassword => {

    // Display the hashed password
    console.log(hashedPassword);

    // Compare the password with hashed password
    // and return its value
    return bcrypt.compare(password, hashedPassword);

}).then(isMatch => {

    // If password matches then display true
    console.log(isMatch);
}).catch(err => {

    // Display error log
    console.log(err);
});

Output:

$2a$08$LKZU9S9WVs3C.S/zpu2U7eua/ocfzD1ytF68QPT5M600auT6M.SxG
true