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Decrypt AES in JavaScript

I am encrypting a text with AES256 in swift language and outputting it as hex. I want to decrypt this code I received with JS, but I could not reach the result. I tried the CryptoJS library but still couldn't get the result I wanted. All I want is the js code that will give me the decoded version when I enter the IV, password and ciphertext.
const crypto = require("crypto");
var key = "";
const iv = "";
const token = "";
function decrypt(token, iv, key) {
const decrypter = crypto.createDecipheriv("aes-256-cbc", key, iv);
let decrypted = decrypter.update(token, "hex", "utf8");
decrypted += decrypter.final("utf8");
return decrypted
}
console.log(decrypt(token, iv, key));
With the Node.js code above, I achieve what I want, but I want to do it with normal JS code, not using node. I don't want to mess with the server. I would be very happy if you help.
EDIT:
I am using CryptoSwift library in Swift language.
func encryption(uuid: String, token: String) -> String {
do {
let aes = try AES(key: String(uuid.prefix(32)), iv: String(uuid.prefix(16)))
let ciphertext = try aes.encrypt(Array(token.utf8))
let encrypttext = ciphertext.toHexString()
return encrypttext
}
catch {
return "error"
}
}
I tried to do something with CryptoJS with the codes from the site below, but it didn't work like the codes in Node.js.
https://embed.plnkr.co/0VPU1zmmWC5wmTKPKnhg/
EDIT2:
I've been trying different things but couldn't quite figure it out. I get an error when I add PBKDF2. I don't fully understand the problem.
var password = "6268890F-9B58-484C-8CDC-34F9C6A9";
var iv = "6268890F-9B58-48";
var cipher = "79a247e48ac27ed33ca3f1919067fa64";
/*
var key = CryptoJS.PBKDF2(password, {
keySize: 32
});
*/
var dec= CryptoJS.enc.Hex.parse(cipher);
const decrypted = CryptoJS.AES.decrypt({
ciphertext: dec
},
password, {
iv: iv,
mode: CryptoJS.mode.CBC,
padding: CryptoJS.pad.Pkcs7
});
console.log(decrypted.toString(CryptoJS.enc.Utf8));
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.2/rollups/aes.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/3.1.2/rollups/pbkdf2.js"></script>

CryptoJS uses WordArrays, so that key, IV and ciphertext have to be converted accordingly. For this purpose the appropriate encoders have to be applied. Furthermore decrypt() expects the ciphertext as CipherParams object.
This results in the following possible CryptoJS implementation:
var ciphertext = "79a247e48ac27ed33ca3f1919067fa64";
var key = "6268890F-9B58-484C-8CDC-34F9C6A9";
var iv = "6268890F-9B58-48";
var ciphertextWA = CryptoJS.enc.Hex.parse(ciphertext);
var keyWA = CryptoJS.enc.Utf8.parse(key);
var ivWA = CryptoJS.enc.Utf8.parse(iv);
var ciphertextCP = { ciphertext: ciphertextWA };
var decrypted = CryptoJS.AES.decrypt(
ciphertextCP,
keyWA,
{ iv: ivWA }
);
console.log(decrypted.toString(CryptoJS.enc.Utf8)); // Apple
<script src="https://cdnjs.cloudflare.com/ajax/libs/crypto-js/4.0.0/crypto-js.min.js"></script>
which is functionally identical to the posted NodeJS code that also successfully decrypts the test data.
Regarding the question asked in the comment about the encodings:
In general, the decryption side must have knowledge of the encodings used for encryption. However, in this case the encodings can be derived from the posted NodeJS code:
For decryption, the input encoding of the ciphertext is specified as 'hex', see decipher.update().
key and iv are defined as strings which are UTF-8 encoded, see crypto.createDecipheriv().
Also, the data used is consistent with these conclusions.
Note that for security reasons a static IV may not be used. Instead, a random IV must be generated for each encryption.
Also, no password may be applied as key, even if it has the right length. If a password is to be used, a key derivation is necessary, e.g. with PBKDF2.
For test purposes, the data is of course enough.

java encryption aes value and javascript encryption value does not match

I have java code which produce aes encryption code for me now I am trying to use it on javascript using crypto-js but both codes provides different keys I dont know why and how to get the same key here is my code
public static String encrypt(String text, byte[] iv, byte[] key)throws Exception{
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
SecretKeySpec keySpec = new SecretKeySpec(key, "AES");
System.out.println("KEY SPECCCC: "+keySpec);
IvParameterSpec ivSpec = new IvParameterSpec(iv);
cipher.init(Cipher.ENCRYPT_MODE,keySpec,ivSpec);
byte [] results = cipher.doFinal(text.getBytes("UTF-8"));
BASE64Encoder encoder = new BASE64Encoder();
return encoder.encode(results);
}
JavaScript code
require(["crypto-js/core", "crypto-js/aes"], function (CryptoJS, AES) {
ciphertext = CryptoJS.AES.encrypt(JSON.stringify(jsondata),
arr.toString(),arr.toString());
});
string to utf-8
var utf8 = unescape(encodeURIComponent(key));
var arr = [];
for (var i = 0; i < utf8.length; i++) {
arr.push(utf8.charCodeAt(i));
}

First of all even tough your code works fine you wont be able to decrypt it back properly because while you are creating your AES cipher in Java you are using CBC Cipher and You are implementing a Padding algorithm which is PKCS5Padding.
So your java code does the followings;
When it gets the input it first divide it into the 16 bits blocks then if your input doesnt divide into the 16 overall then the reminders will be padded for filling the block with the same number of reminder.You can see what i mean by the following picture.
So it will do the encryption with the padded ciphers in the java side but in the Javascript Part You neither declare what type of Mode Aes will use nor declaring the what type of Padding it suppose to do. So you should add those values into the your code.You can make search following code parts.
mode:CryptoJS.mode.CBC,
padding: CryptoJS.pad.Pkcs7
About the different keys it is occuring because you are sending a Byte[] in to the your Encrypt method then use this unknown Byte[] while you are creating your Key.You didnt mention why your encryption method will be used in your program but you should create that "Byte[] key" same way in the both method.For instance you can refer following code as a example of generating that but it is not secure way of generating keys I just added it for showing you what I mean by you should generate both keys in the same way.
//DONT USE THIS IMPLEMENTATION SINCE IT IS NOT SAFE!
byte[] key = (username + password).getBytes("UTF-8");

Java code generates an encrypted string and for JavaScript to also generate same encrypted string, Following code works!
(function (CryptoJS) {
var C_lib = CryptoJS.lib;
// Converts ByteArray to stadnard WordArray.
// Example: CryptoJS.MD5(CryptoJS.lib.ByteArray ([ Bytes ])).toString(CryptoJS.enc.Base64);
C_lib.ByteArray = function (arr) {
var word = [];
for (var i = 0; i < arr.length; i += 4) {
word.push (arr[i + 0] << 24 | arr[i + 1] << 16 | arr[i + 2] << 8 | arr[i + 3] << 0);
}
return C_lib.WordArray.create (word, arr.length);
};
})(CryptoJS);
var IVstring = CryptoJS.lib.ByteArray(your IV bytearray).toString(CryptoJS.enc.Base64);
var keystring = CryptoJS.lib.ByteArray(your KEY bytearray).toString(CryptoJS.enc.Base64);
var text = 'texttobeencrypted';
var key = CryptoJS.enc.Base64.parse(keystring);
var iv = CryptoJS.enc.Base64.parse(IVstring);
var encrypted = CryptoJS.AES.encrypt(text, key, {iv: iv});
console.log(encrypted.toString());
Edited: Removed dangerous third party resource reference.
aes encryption javascript cryptojs java

different output for JAVA vs javascript AES 256 cbc

Im trying to create an AES 256 cbc encryption using java and I need to emulate EXACTLY this javascript code (I know the iv is the same as the key (turnicated to 16 bytes), that's how it is from the site i'm trying to log into using java)
var recievedStr = "MDk4NTY1MDAyMjg2MTU1OA=="; //some
var key = CryptoJS.enc.Base64.parse(recievedStr);
var iv = CryptoJS.enc.Base64.parse(recievedStr);
var pw = "PASSWORD";
var encres = CryptoJS.AES.encrypt(pw, key, {iv:iv, keySize: 256, mode: CryptoJS.mode.CBC, padding: CryptoJS.pad.Pkcs7});
var finalStr = encres.toString();
finalStr will be : Su92ZXLm/MdOyruRnWDRqQ==
I need to make a java code that will output exactly the same output as finalStr from the javascript.
Im using bouncy castle for that.
String recievedStr = "MDk4NTY1MDAyMjg2MTU1OA==";
String pw = "PASSWORD";
AESEngine blockCipher = new AESEngine();
CBCBlockCipher cbcCipher = new CBCBlockCipher(blockCipher);
BufferedBlockCipher cipher = new PaddedBufferedBlockCipher (cbcCipher);
byte[] key = encodeBase64(recievedStr);
byte [] iv = java.util.Arrays.copyOf(key,16);
byte[] input = pw.getBytes();
ParametersWithIV pwIV= new ParametersWithIV(new KeyParameter(key),iv);
cipher.init(true, pwIV);
byte[] cipherText = new byte[cipher.getOutputSize(input.length)];
int outputLen = cipher.processBytes(input, 0, input.length, cipherText, 0);
try
{
cipher.doFinal(cipherText, outputLen);
}
catch (CryptoException ce)
{
System.err.println(ce);
}
System.out.println(new String(Base64.encodeBase64(cipherText)));
this will output : qEGQ1PC/QKxfAxGBIbLKpQ==
while I can decrypt it to the original input, that is not what i want.
I need my java code to output exactly what the javascript did.
I have 0 ideas left on how to approach this.
Thanks.
EDIT: problem was solved, I had to decode the received string to base64 instead of encoding it.

I think you are on the right track. But I think you are running with AES-128 instead of AES-256. If you have a look at Java 256-bit AES Password-Based Encryption I think maybe you can find something useful.

Encrypting data with forgejs on the client side, and decrypting with ruby

For a given project, I'm looking to encrypt a piece of data with AES 256, and then RSA encrypt the key. I've been using Forge and the Encryptor gem in ruby, and i can't seem get matching encryption values:
var key = 'strengthstrengthstrengthstrength';
var iv = 'cakecakecakecakecakecakecakecake';
var cipher = forge.aes.createEncryptionCipher(key, 'CBC');
cipher.start(iv);
cipher.update(forge.util.createBuffer("some string"));
cipher.finish();
var encrypted = cipher.output;
console.log(btoa(encrypted.data)); // outputs: CjLmWObDO2Dlwa5tJnRBRw==
Then in IRB:
Encryptor.encrypt 'some string', :key => 'strengthstrengthstrengthstrength', :key => 'cakecakecakecakecakecakecakecake'
Base64.encode64 _
# outputs: C9Gtk9YfciVMJEsbhZrQTw==\n
Over using string values for Key & IV, tried:
var key = forge.random.getBytesSync(32);
var iv = forge.random.getBytesSync(32);
Then doing a btoa() call on each of them. Using the Base64.decode64 on the ruby side, before passing them to Encryptor.decrypt, but still no luck.
Any idea where i've gone wrong?

I managed to get it to work. Since i'm just using one key to encrypt one value, i just used the key as the IV & Salt as well. This is not recommended if you are using the key to encrypt multiple values. You will then need to generate proper salt & iv values.
Also the gen key value is a pretty poor way, as Math.random is not secure. Just ran out of time to do this properly, but works okay for this case.
var Encryption = (function () {
var api = {
getKey: function () {
var possible = "ABCDEFabcdef0123456789";
var key = '';
for (var i = 0; i < 32; i++) {
key += possible.charAt(Math.floor(Math.random() * possible.length));
}
return key;
},
encryptPII: function (rawKey, value) {
var salt = rawKey;
var iv = rawKey;
var key = forge.pkcs5.pbkdf2(rawKey, salt, 2000, 32);
var cipher = forge.aes.createEncryptionCipher(key, 'CBC');
cipher.start(iv);
cipher.update(forge.util.createBuffer(value));
cipher.finish();
return btoa(cipher.output.data);
}
};
return api;
})();
The rawKey is the value returned from getKey(). The value property is the the string to be encrypted. I use the rawkey for iv & salt values, generate a key in the same way that the Encryptor gem in ruby does. Use forge to then encrypt the string value.
If i take the base64, decode it in ruby, and pass the same rawKey value to the encryptor gem for key, salt and iv, it works.

CryptoJS and Pycrypto working together

I'm encrypting a string in a web application using CryptoJS (v 2.3), and I need to decrypt it on the server in Python, so I'm using PyCrypto. I feel like I'm missing something because I can't can it working.
Here's the JS:
Crypto.AES.encrypt('1234567890123456', '1234567890123456',
{mode: new Crypto.mode.CBC(Crypto.pad.ZeroPadding)})
// output: "wRbCMWcWbDTmgXKCjQ3Pd//aRasZ4mQr57DgTfIvRYE="
The python:
from Crypto.Cipher import AES
import base64
decryptor = AES.new('1234567890123456', AES.MODE_CBC)
decryptor.decrypt(base64.b64decode("wRbCMWcWbDTmgXKCjQ3Pd//aRasZ4mQr57DgTfIvRYE="))
# output: '\xd0\xc2\x1ew\xbb\xf1\xf2\x9a\xb9\xb6\xdc\x15l\xe7\xf3\xfa\xed\xe4\xf5j\x826\xde(m\xdf\xdc_\x9e\xd3\xb1'

Here is a version with CryptoJS 3.1.2. Always beware of the following things (use the same in both languages):
Mode of operation (CBC in this case)
Padding (Zero Padding in this case; better use PKCS#7 padding)
Key (the same derivation function or clear key)
Encoding (same encoding for key, plaintext, ciphertext, ...)
IV (generated during encryption, passed for decryption)
If a string is passed as the key argument to the CryptoJS encrypt() function, the string is used to derive the actual key to be used for encryption. If you wish to use a key (valid sizes are 16, 24 and 32 byte), then you need to pass it as a WordArray.
The result of the CryptoJS encryption is an OpenSSL formatted ciphertext string. To get the actual ciphertext from it, you need to access the ciphertext property on it.
The IV must be random for each encryption so that it is semantically secure. That way attackers cannot say whether the same plaintext that was encrypted multiple times is actually the same plaintext when only looking at the ciphertext.
Below is an example that I have made.
JavaScript:
var key = CryptoJS.enc.Utf8.parse('1234567890123456'); // TODO change to something with more entropy
function encrypt(msgString, key) {
// msgString is expected to be Utf8 encoded
var iv = CryptoJS.lib.WordArray.random(16);
var encrypted = CryptoJS.AES.encrypt(msgString, key, {
iv: iv
});
return iv.concat(encrypted.ciphertext).toString(CryptoJS.enc.Base64);
}
function decrypt(ciphertextStr, key) {
var ciphertext = CryptoJS.enc.Base64.parse(ciphertextStr);
// split IV and ciphertext
var iv = ciphertext.clone();
iv.sigBytes = 16;
iv.clamp();
ciphertext.words.splice(0, 4); // delete 4 words = 16 bytes
ciphertext.sigBytes -= 16;
// decryption
var decrypted = CryptoJS.AES.decrypt({ciphertext: ciphertext}, key, {
iv: iv
});
return decrypted.toString(CryptoJS.enc.Utf8);
}
Python 2 code with pycrypto:
BLOCK_SIZE = 16
key = b"1234567890123456" # TODO change to something with more entropy
def pad(data):
length = BLOCK_SIZE - (len(data) % BLOCK_SIZE)
return data + chr(length)*length
def unpad(data):
return data[:-ord(data[-1])]
def encrypt(message, key):
IV = Random.new().read(BLOCK_SIZE)
aes = AES.new(key, AES.MODE_CBC, IV)
return base64.b64encode(IV + aes.encrypt(pad(message)))
def decrypt(encrypted, key):
encrypted = base64.b64decode(encrypted)
IV = encrypted[:BLOCK_SIZE]
aes = AES.new(key, AES.MODE_CBC, IV)
return unpad(aes.decrypt(encrypted[BLOCK_SIZE:]))
Warning: Keep in mind that both python2 and pycrypto are obsolete, so the code has to be adjusted to fit python3 and pycryptodome.
Other considerations:
It seems that you want to use a passphrase as a key. Passphrases are usually human readable, but keys are not. You can derive a key from a passphrase with functions such as PBKDF2, bcrypt or scrypt.
The code above is not fully secure, because it lacks authentication. Unauthenticated ciphertexts may lead to viable attacks and unnoticed data manipulation. Usually the an encrypt-then-MAC scheme is employed with a good MAC function such as HMAC-SHA256.

I had to port a Javascript implementation of AES encryption/decryption which was using crypto-js library, to Python3.
Basically, my approach was to run the debugger on the existing JS code and look at variables getting filled in each step. I was able to figure out the equivalent methods to do the same in python as well.
Here is how I ported it using pycryptodome library which has some useful features.
AES.js
var CryptoJS = require("crypto-js");
var Base64 = require("js-base64");
function decrypt(str, secret) {
try {
var _strkey = Base64.decode(secret);
var reb64 = CryptoJS.enc.Hex.parse(str);
var text = reb64.toString(CryptoJS.enc.Base64);
var Key = CryptoJS.enc.Base64.parse(_strkey.split(",")[1]); //secret key
var IV = CryptoJS.enc.Base64.parse(_strkey.split(",")[0]); //16 digit
var decryptedText = CryptoJS.AES.decrypt(text, Key, { keySize: 128 / 8, iv: IV, mode: CryptoJS.mode.CBC, padding: CryptoJS.pad.Pkcs7 });
return decryptedText.toString(CryptoJS.enc.Utf8); //binascii.unhexlify(decryptedText)
} catch (e) {
console.log("Error", e)
}
}
function encrypt(str, secret) {
str = Math.random().toString(36).substring(2, 10) + str;
var _strkey = Base64.decode(secret);
_strkey.split(",");
var text = CryptoJS.enc.Utf8.parse(str);
var Key = CryptoJS.enc.Base64.parse(_strkey.split(",")[1]); //secret key
var IV = CryptoJS.enc.Base64.parse(_strkey.split(",")[0]); //16 digit
var encryptedText = CryptoJS.AES.encrypt(text, Key, { keySize: 128 / 8, iv: IV, mode: CryptoJS.mode.CBC, padding: CryptoJS.pad.Pkcs7 });
var b64 = encryptedText.toString();
var e64 = CryptoJS.enc.Base64.parse(b64);
var eHex = e64.toLocaleString(CryptoJS.enc.Hex);
return eHex.toUpperCase();
}
const secret = "V1VWTVRFOVhJRk5WUWsxQlVrbE9SUT09LFRrOUNUMFJaSUZkSlRFd2dTMDVQVnc9PQ=="
const data = "THIS IS MY SECRET MESSAGE!"
encData = EncryptText2(data, secret)
decData = DecryptText2(encData, secret)
console.log("encryptedData", encData)
console.log("decryptedData", decData)
AESify.py
import string
import random
import base64
import binascii
from Crypto.Cipher import AES
from Crypto.Util.Padding import pad, unpad
class AESify:
def __init__(self, key=None, iv=None,secret = None, block_len=16, salt_len= 8):
self.key = key
self.iv = iv
self.salt_len = salt_len
self.block_len = block_len
self.mode = AES.MODE_CBC
if(secret):
self.useSecret(secret)
if(self.key is None and self.iv is None):
raise Exception("No key , IV pair or secret provided")
#staticmethod
def makeSecret(key, iv):
if(len(key) % 8 != 0):
raise Exception("Key length must be a mutliple of 8")
if(len(iv) % 8 != 0):
raise Exception("Initial vector must be a multiple of 8")
key64 = base64.b64encode(key.encode()).decode()
iv64 = base64.b64encode(iv.encode()).decode()
secret = iv64 + "," + key64
secret64 = base64.b64encode(secret.encode()).decode()
return secret64
def useSecret(self, secret):
iv64, key64 = base64.b64decode(secret).decode().split(",") # decode and convert to string
self.iv = base64.b64decode(iv64)
self.key = base64.b64decode(key64)
return self
def encrypt(self, text):
text = self.add_salt(text, self.salt_len)
cipher = AES.new(self.key, self.mode, self.iv)
text = cipher.encrypt(pad(text.encode('utf-8'), self.block_len))
return binascii.hexlify(text).decode()
def decrypt(self, data):
text = binascii.unhexlify(data) # UNHEX and convert the encrypted data to text
cipher = AES.new(self.key, self.mode, self.iv)
return unpad(cipher.decrypt(text), self.block_len).decode('utf-8')[self.salt_len:]
def add_salt(self, text, salt_len):
# pre-pad with random salt
salt = ''.join(random.choice(string.ascii_letters + string.digits) for _ in range(salt_len))
text = salt + text
return text
main.py
from AESify import AESify
key , iv = "NOBODY WILL KNOW", "YELLOW SUBMARINE"
# contains IV and key
secret = AESify.makeSecret(key, iv)
aes = AESify(secret= secret, block_len=16, salt_len=4)
msg = "THIS IS MY SECRET MESSAGE"
encrypted = aes.encrypt(msg)
decrypted = aes.decrypt(encrypted)
print(f"{secret=}")
print(f"{encrypted=}")
print(f"{decrypted=}")

Note : salt , iv , padding should be same in js and python
generate salt and iv value and convert it into a byte string uisng CryptoJS.enc.Utf8.parse()
js file
var encrypted = CryptoJS.AES.encrypt(JSON.stringify(json_data), CryptoJS.enc.Utf8.parse(data['salt']) , { iv: CryptoJS.enc.Utf8.parse(data['iv']) , mode: CryptoJS.mode.CBC , padding: CryptoJS.pad.Pkcs7});
en_data = encrypted.ciphertext.toString(CryptoJS.enc.Base64)
send this encrypted data to the python file
python file
from Crypto.Util.Padding import pad, unpad
ct = request.POST['encrypted_data']
data = base64.b64decode(ct)
cipher1 = AES.new(salt, AES.MODE_CBC, iv)
pt = unpad(cipher2.decrypt(data), 16)
data = json.loads(pt.decode('utf-8'))
pad and upad in pycrypto by default uses pkcs#7
salt and iv value should in byte string