Not able to use the info via Terminal in the code sample

Question

I am newbie with JS and trying to write a simple code to encrypt and decrypt the info via Javascript, the sample code is below. It is working till the encryption, but I want to take the 'mystr' into the decryption section back, which is however not working. Any clue would be helpful, thnaks!

var crypto = require('crypto');                                                                 
var mykey = crypto.createCipher('aes-256-cbc', 'mypassword');                                   

const readline = require('readline').createInterface({                                          
    input: process.stdin,                                                                       
    output: process.stdout                                                                      
})                                                                                              


readline.question(`The string to Encrypt?`, (secret) => {                                       
    var mystr = mykey.update(`${secret}`, 'utf8', 'hex')                                        
    mystr += mykey.final('hex');                                                                
    console.log(`${mystr}`);                                                                    
   // readline.close()  

     //deencryption
    var mykey2 = crypto.createDecipher('aes-256-cbc', 'mypassword');                                                                                                                            
    var mystr2 = mykey2.update(mystr, 'hex', 'utf8');               
    mystr2 += mykey2.final('utf8');                                                              

    console.log(`${decrypt}`);                                                                  
    readline.close()                                                                            
})                                                                                              

Answer 1

You need to create a decipher:

var crypto = require('crypto');

const readline = require('readline').createInterface({
    input: process.stdin,
    output: process.stdout
})

readline.question(`The string to Encrypt?`, (secret) => {

    //create cipher
    var cipher = crypto.createCipher('aes-256-cbc', 'mypassword');
    //encrypt string
    var mystr = cipher.update(`${secret}`, 'utf8', 'hex')
    mystr += cipher.final('hex');
    console.log(`${mystr}`);

    //create decipher
    var decipher = crypto.createDecipher('aes-256-cbc', 'mypassword');
    //decrypt string
    var mystr2 = decipher.update(`${mystr}`, 'hex', 'utf8')
    mystr2 += decipher.final('utf8');

    console.log(`${mystr2}`);
    readline.close()
})

For more infos look here: https://www.w3schools.com/nodejs/ref_crypto.asp

Answer 2

look like, it was some silly mistake after adding decipher, it is working now:) thanks all for your comments, it help me to fix it.

Here the working code:

var crypto = require('crypto');                                                                                                                                          
var mykey = crypto.createCipher('aes-256-cbc', 'mypassword');                                                                                                            
var mykey2 = crypto.createDecipher('aes-256-cbc', 'mypassword');                                                                                                         


const readline = require('readline').createInterface({                                                                                                                   
    input: process.stdin,                                                                                                                                                
    output: process.stdout                                                                                                                                               
})                                                                                                                                                                       


var mystr = '';                                                                                                                                                          
var mystr2 = '';                                                                                                                                                         

readline.question(`The string to Encrypt?`, (secret) => {                                                                                                                
    mystr = mykey.update(`${secret}`, 'utf8', 'hex')                                                                                                                     
    mystr += mykey.final('hex');                                                                                                                                         
    console.log(`${mystr}`);                                                                                                                                             

    mystr2 = mykey2.update(mystr, 'hex', 'utf8');                                                                                                                        
    mystr2 += mykey2.final('utf8');                                                                                                                                      

    console.log(`${mystr2}`);                                                                                                                                            
    readline.close()                                                                                                                                                     
})