"CTR" mode is not same as "aes-256-ctr" in crypto library.

[Just4test]

I have some file which encrypted by aes-js CTR mode.
Now I want to decrypt them using library "crypto". I think ctr in crypto should be "aes-256-ctr", but I can't decrypt them.

Here 's my demo code:(I use node v8.11.2)

const aesjs = require('aes-js')
const crypto = require('crypto')
const key = new Buffer([0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
	16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31])
const text = 'Text may be any length you wish, no padding is required.Now I want to decrypt them using library "crypto".'
const buffer = Buffer.from(text, 'utf8')

function byAesjs(bytes){
	let aesCtr = new aesjs.ModeOfOperation.ctr(key)
	let encryptedBytes = Buffer(aesCtr.encrypt(bytes))
	return encryptedBytes
}

function byCrypto(bytes){
	let cipher = crypto.createCipher('aes-256-ctr', key)
	let encryptedBytes = cipher.update(bytes)
	encryptedBytes = Buffer.concat([encryptedBytes, cipher.final()])
	return encryptedBytes
}

let temp = byAesjs(buffer)
temp = byAesjs(temp)
console.log('======================================')
console.log(temp.toString('utf8') == text)

temp = byCrypto(buffer)
temp = byCrypto(temp)
console.log('======================================')
console.log(temp.toString('utf8') == text)

temp = byAesjs(buffer)
temp = byCrypto(temp)
console.log('======================================')
console.log(temp.toString('utf8') == text) //return false

[mikegwhit]

I see that you are relying on the symmetric nature of the algorithm. Also, per the examples, sometimes a conversion to a hex string helped me when wrapping the Node API.

[Just4test]

I see that you are relying on the symmetric nature of the algorithm. Also, per the examples, sometimes a conversion to a hex string helped me when wrapping the Node API.

So.... it is possable to decrypt it using crypto? What should I do?
I've tried replace "crypto.createCipher('aes-256-ctr', key)" to "crypto.createCipher('aes-256-ctr', key.toString('hex'))" But it doesn't work either.
Thank you.

[mikegwhit]

    encrypt(data) {
        const iv = this.initializationVector();
        const cipher = this.crypto.createCipheriv(this.algorithm, 
            this.key, iv);
        let encrypted = new Buffer(iv).toString('base64') + 
            cipher.update(data, 'utf8', 'base64') +
            cipher.final('base64');
        this.hmac = this.crypto.createHmac('sha512', this.key)
            .update(encrypted).digest('hex');

        return encrypted;
    }

That's the fn I use for crypto in my library. A simple symmetric wrapper around the native library.

Node's native lib is finicky. It took me some time to figure out.

I haven't yet built a bridge to the browser, but it's on my TODO list which is how I landed here. I'm interested in the same problem you're solving in other words :)

[mikegwhit]

IIRC base64 may be what Node prefers but I don't exactly recall. There may also be padding-related issues since the aes-js library seems to indicate fragility around fixed length keys.