(encrypt + decrypt).js

gistfile1.txt

const encrypt = (text, email) => {

    const iv = crypto.randomBytes(IV_LENGTH)
    const cipher = crypto.createCipheriv('aes-256-cbc', new Buffer(ENCRYPTION_KEY), iv)
    let encrypted = cipher.update(text)

    encrypted = Buffer.concat([encrypted, cipher.final()])

    return `${iv.toString('hex')}:${encrypted.toString('hex')}`
}

const decrypt = (text, email) => {
    const textParts = text.split(':')

    const iv = new Buffer(textParts.shift(), 'hex')
    
    const encryptedText = new Buffer(textParts.join(':'), 'hex')
    const decipher = crypto.createDecipheriv('aes-256-cbc', new Buffer(ENCRYPTION_KEY), iv)
    let decrypted = decipher.update(encryptedText)

    decrypted = Buffer.concat([decrypted, decipher.final()])

    return decrypted.toString()
}