Convert PHP password code into JavaScript/Node.js

I'm converting a website from PHP to Node.js/JavaScript. I have users in the site already and I don't want to force users to recreate their password when I switch to the new code, so I need to convert the PHP password hashing/verification code into JavaScript. The code uses the PHP crypt library. I have attached a PHP script that separates all the required logic into a small file. I need someone who understands the crypt and mcrypt_create_iv functions in PHP who can convert everything into JavaScript so that all my existing user accounts will still be verified using the JavaScript validation code.