Develop Reference

TripleDES Java Encryprion to Javascript Decryption

I am using Java to encrypt a text payload with Triple DES. First I create an ephemeral key that I will use for encrypting the payload:
private byte[] createEphemeralKey() throws Exception {
KeyGenerator keygen = KeyGenerator.getInstance("DESede");
keygen.init(168);
return keygen.generateKey().getEncoded();
}
Then I encrypt my payload with said key:
private String encryptTripleDES(byte[] ephemeralKey, String payload) throws Exception {
Cipher cipher = Cipher.getInstance("DESede/ECB/NoPadding");
cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(ephemeralKey, "DESede"));
byte[] plainTextBytes = payload.getBytes();
byte[] cipherText = cipher.doFinal(plainTextBytes);
return Base64.getEncoder().encodeToString(cipherText);
}
Also need a padding function to ensure the data length is divisable by 8:
private String adjustPadding(String input, int blockSize) {
int len = input.length() % blockSize;
int paddingLength = (len == 0) ? 0 : (blockSize - len);
while (paddingLength > 0) {
input += "F";
paddingLength--;
}
return input;
}
And here is my process end to end:
String data = "Marnus"
byte[] = ephemeralKey = createEphemeralKey();
String adjustedData = adjustPadding (data,8);
String encryptedPayload = encryptTripleDES(ephemeralKey, adjustedData);
String encodedKey = Base64.getEncoder().encodeToString(ephemeralKey)
So I take the 2 variables encryptedPayload and encodedKey, that are both Base64 encoded string, and send it off via HTTP to node express app.
In the Javascript side of things, I use node-forge - Here is the part of my express app that does the decryption:
let nodeBuffer = Buffer.from(data, 'base64')
let input = forge.util.createBuffer(nodeBuffer.toString('binary'))
// 3DES key and IV sizes
let keySize = 24;
let ivSize = 8;
let derivedBytes = forge.pbe.opensslDeriveBytes(ephemeralKey, null, keySize + ivSize);
let buffer = forge.util.createBuffer(derivedBytes);
let key = buffer.getBytes(keySize)
let iv = buffer.getBytes(ivSize)
let decipher = forge.cipher.createDecipher('3DES-ECB', key)
decipher.start({iv: iv})
decipher.update(input)
console.log('decipher result', decipher.finish())
let decryptedResult = decipher.output.data;
Here is an Triples DES example in the node-forge docs:
A few notes:
I create a node-forge buffer from a regular buffer since I don't have a input file like the examples gives. Here is how the docs states one should create one buffer from the other:
*I use base64 as that is what I used in the java side to encode the data that was sent.
Then, I dont have a salt so I left the 2'nd param null in opensslDeriveBytes as specified in the docs I should do.
Thirdly, I am also not sure if my keysize of 24 is correct?
My results
So doing an end to end test yields the following:
In my Java app, the test data was "Marnus", the encryptedPayload was ez+RweSAd+4= and the encodedKey was vCD9mBnWHPEBiQ0BGv7gc6GUCOoBgLCu.
Then in my javascript code data was obviously ez+RweSAd+4=(encryptedPayload) and the ephemeralKey was vCD9mBnWHPEBiQ0BGv7gc6GUCOoBgLCu(encodedKey).
After the decryption ran, the value of decryptedResult was ©ýÕ?µ{', which is obviously just garbage since it was not encoded yet, but I cant figure out which encoding to use?
I tried using forge.util.encode64(decipher.output.data), but that just gave me qf3VP7UYeyc=, which is not right.
For what it's worth, here is the type that decipher.output

With a lot more tweaking and testing different options, I got it working - and the good news is I managed to get it all working with the built in crypto library in nodejs (v12.18.4).
First things first, the JAVA side just needs a change to the key size (from 168 to 112), the rest remains the same - see below example as one single method (should be split up in final implementation of course for testability and usability):
//Some data:
String payload = "{\"data\":\"somedata\"}";
// Create Key
KeyGenerator keygen = KeyGenerator.getInstance("DESede");
keygen.init(112);
byte[] ephemeralKey = keygen.generateKey().getEncoded();
// Adjust the data, see adjustPadding method in the question for details.
String data = adjustPadding (payload,8);
// Wil now be "{"data":"somedata"}FFFFF", can just chop off extra in JS if need be. When sending JSON one knows the end of the object will always be "}"
// Do Encrypt
Cipher cipher = Cipher.getInstance("DESede/ECB/NoPadding");
cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(ephemeralKey, "DESede"));
byte[] plainTextBytes = data.getBytes();
byte[] cipherText = cipher.doFinal(plainTextBytes);
String encryptedPayload = Base64.getEncoder().encodeToString(cipherText);
//Lastly, Base64 the key so you can transport it too
String encodedKey = Base64.getEncoder().encodeToString(ephemeralKey)
on the Javascript side of things we keep it simple:
// I'm using TS, so change the import if you do plain JS
import crypto = require('crypto')
//need bytes from the base64 payload
let buff = Buffer.from(ephemeralKey, 'base64')
const decipher = crypto.createDecipheriv('des-ede3', buff, null)
decipher.setAutoPadding(false)
let decrypted = decipher.update(data, 'base64', 'utf8')
decrypted += decipher.final('utf8')
console.log(decrypted)
//{"data":"somedata"}FFFFF"

AES encryption in node resulting is different output compared to java

I'm trying to port the Java code for AES ECB encryption into node.js
The issues is that the output from java and node are not the same.
Here's the java code
public static final String DEFAULT_ENCODING = "UTF-8";
public static final String SEC_PROVIDER = "SunJCE";
public static final String AES_ALGORITHM = "AES";
public static final String RIJNDAEL_CIPHER = **"Rijndael/ECB/NoPadding"**;
public static final int **CIPHER_PAD_SIZE = 32**;
public static final String HEX_KEY = "3b6ce332ca3b6519eac769710f41ca5c";
public static String encryptData(String text, String hexKey) throws
Exception {
byte[] b1 = Hex.decodeHex(HEX_KEY.toCharArray());
SecretKey key = new SecretKeySpec(b1, AES_ALGORITHM);
Cipher cipher = Cipher.getInstance(RIJNDAEL_CIPHER, SEC_PROVIDER);
text = padRightToMod(text, CIPHER_PAD_SIZE);
byte[] buf = text.getBytes(DEFAULT_ENCODING);
cipher.init(Cipher.ENCRYPT_MODE, key);
buf = cipher.doFinal(buf);
String result = new String(Hex.encodeHex(buf));
result = result.toUpperCase();
return result;
}
// ensure block size of 32
public static String padRightToMod(String text, int mod) {
if (text == null || mod <= 0) {
return text;
}
final int len = text.length();
StringBuilder buf = new StringBuilder(512);
buf.append(text);
for (int i = len; i % mod > 0; i++) {
buf.append(" ");
}
String rs = buf.toString();
System.out.println(rs.length());
return rs;
}
// Call to the encrypt function
String encText = encryptData("Hello", HEX_KEY);
The result is CC0AC95B5FFD4758DBFA40F909C285F0F86A8F19ED1A12C1BFC098348A2AC683
And with this javascript code
crypto = require('crypto');
function encrypt(data,key) {
var cipher = crypto.createCipher('**aes-128-ecb**', key); //create aes cipher
var encrypted = cipher.update(data,'utf8', 'hex'); //output as hex
return encrypted;
}
function padRightTo32(str) // ensure block size of 32
{
len=str.length;
for(i=len; i%32>0; i++){
str=str +" ";
}
return str;
}
// call to encryption function
hexkey="3b6ce332ca3b6519eac769710f41ca5c"
encStr=encrypt(padRightTo32("Hello"),hexKey);
console.log(encStr);
The result is
1B928CF3C18D53BA5138DD1484D181939FD2B7BB2A17AE6A79664488B5C12652
==== Update ======
I tried https://github.com/Snack-X/rijndael-js implementaiton form github with this code
const Rijndael = require("./node_modules/node-rijndael-master");
function padRightTo32(str)
{
len=str.length;
for(i=len; i%32>0; i++){
str=str +" ";
}
console.log(str);
console.log(str.length);
return str;
}
let key = "3b6ce332ca3b6519eac769710f41ca5c";
let original = padRightTo32("Hello");
let cipher = new Rijndael(key, "ecb");
let ciphertext = cipher.encrypt(original, 128);
console.log(ciphertext.toString("hex"));
I get this result e97282fb5838a9c78e6df1f1b4aad108aa010418ec573d74b9c991f4e897e752 but not the encrypted text that Iget from in java. Trying the 256 block size doesn't help either.
what I'm missing that is resulting in a different output?

Concerning your key you have to convert your hex-string into binary data using a buffer (see e.g. Encrypt binary data with aes-ecb on node.js).
Moreover, you have to use the method crypto.createCipheriv to instantiate the cipher (see e.g. https://nodejs.org/api/crypto.html#crypto_crypto_createcipheriv_algorithm_key_iv_options).
The currently used (deprecated) method crypto.creataCipher expects a password and generates the key from the password (see e.g. https://nodejs.org/api/crypto.html#crypto_crypto_createcipher_algorithm_password_options).
The following code
crypto = require('crypto');
function encrypt(data,key) {
var cipher = crypto.createCipheriv('aes-128-ecb', key,''); //create aes-128 cipher
var encrypted = cipher.update(data,'utf8', 'hex'); //output as hex
return encrypted;
}
function padRightTo32(str) { // ensure block size of 32
len=str.length;
for(i=len; i%32>0; i++) {
str=str +" ";
}
return str;
}
// call to encryption function
var hexKey = new Buffer('3b6ce332ca3b6519eac769710f41ca5c', 'hex'); // 16 Byte-key
encStr=encrypt(padRightTo32("Hello"),hexKey);
console.log(encStr);
has the output
cc0ac95b5ffd4758dbfa40f909c285f0f86a8f19ed1a12c1bfc098348a2ac683
which is equal to the output of the Java code.
In Java the length of the key defines the used AES-variant, e.g. if you choose a 16-Byte key AES-128 is used, if a 32-Byte key is chosen, AES-256 is used.
In the nodejs-code you have to explicitly specifiy the AES-variant, i.e. aes-128-ecb for a 16-Byte key, and aes-256-ecb for a 32-Byte key etc.
As already mentioned in the comments ECB in't a secure mode (see e.g. https://crypto.stackexchange.com/questions/20941/why-shouldnt-i-use-ecb-encryption).
I don't know if there is really a difference between Rijndael/ECB/NoPadding and AES/ECB/NoPadding concerning the cipher-instantiation in Java. In my testcases at least the results are identical. Thus, for the nodejs-code the selection of aes-128-ecb (for 16-Byte key) or aes-256-ecb (for 32-Byte keys) should work.

How to decrypt password from JavaScript CryptoJS.AES.encrypt(password, passphrase) in Python

I have a password which is encrypt from JavaScript via
var password = 'sample'
var passphrase ='sample_passphrase'
CryptoJS.AES.encrypt(password, passphrase)
Then I tried to decrypt the password comes from JavaScript in Python:
from Crypto.Cipher import AES
import base64
PADDING = '\0'
pad_it = lambda s: s+(16 - len(s)%16)*PADDING
key = 'sample_passphrase'
iv='11.0.0.101' #------> here is my question, how can I get this iv to restore password, what should I put here?
key=pad_it(key) #------> should I add padding to keys and iv?
iv=pad_it(iv) ##
source = 'sample'
generator = AES.new(key, AES.MODE_CFB,iv)
crypt = generator.encrypt(pad_it(source))
cryptedStr = base64.b64encode(crypt)
print cryptedStr
generator = AES.new(key, AES.MODE_CBC,iv)
recovery = generator.decrypt(crypt)
print recovery.rstrip(PADDING)
I checked JS from browser console, it shows IV in CryptoJS.AES.encrypt(password, passphrase) is a object with some attributes( like sigBytes:16, words: [-44073646, -1300128421, 1939444916, 881316061]). It seems generated randomly.
From one web page, it tells me that JS has two way to encrypt password
(reference link ):
a. crypto.createCipher(algorithm, password)
b. crypto.createCipheriv(algorithm, key, iv)
What I saw in JavaScript should be option a. However, only option b is equivalent to AES.new() in python.
The questions are:
How can I restore this password in Python without changing JavaScript code?
If I need IV in Python, how can I get it from the password that is used in JavaScript?

You will have to implement OpenSSL's EVP_BytesToKey, because that is what CryptoJS uses to derive the key and IV from the provided password, but pyCrypto only supports the key+IV type encryption. CryptoJS also generates a random salt which also must be send to the server. If the ciphertext object is converted to a string, then it uses automatically an OpenSSL-compatible format which includes the random salt.
var data = "Some semi-long text for testing";
var password = "some password";
var ctObj = CryptoJS.AES.encrypt(data, password);
var ctStr = ctObj.toString();
out.innerHTML = ctStr;
<script src="https://cdn.rawgit.com/CryptoStore/crypto-js/3.1.2/build/rollups/aes.js"></script>
<div id="out"></div>
Possible output:
U2FsdGVkX1+ATH716DgsfPGjzmvhr+7+pzYfUzR+25u0D7Z5Lw04IJ+LmvPXJMpz
CryptoJS defaults to 256 bit key size for AES, PKCS#7 padding and CBC mode. AES has a 128 bit block size which is also the IV size. This means that we have to request 32+16 = 48 byte from EVP_BytesToKey. I've found a semi-functional implementation here and extended it further.
Here is the full Python (tested with 2.7 and 3.4) code, which is compatible with CryptoJS:
from Cryptodome import Random
from Cryptodome.Cipher import AES
import base64
from hashlib import md5
BLOCK_SIZE = 16
def pad(data):
length = BLOCK_SIZE - (len(data) % BLOCK_SIZE)
return data + (chr(length)*length).encode()
def unpad(data):
return data[:-(data[-1] if type(data[-1]) == int else ord(data[-1]))]
def bytes_to_key(data, salt, output=48):
# extended from https://gist.github.com/gsakkis/4546068
assert len(salt) == 8, len(salt)
data += salt
key = md5(data).digest()
final_key = key
while len(final_key) < output:
key = md5(key + data).digest()
final_key += key
return final_key[:output]
def encrypt(message, passphrase):
salt = Random.new().read(8)
key_iv = bytes_to_key(passphrase, salt, 32+16)
key = key_iv[:32]
iv = key_iv[32:]
aes = AES.new(key, AES.MODE_CBC, iv)
return base64.b64encode(b"Salted__" + salt + aes.encrypt(pad(message)))
def decrypt(encrypted, passphrase):
encrypted = base64.b64decode(encrypted)
assert encrypted[0:8] == b"Salted__"
salt = encrypted[8:16]
key_iv = bytes_to_key(passphrase, salt, 32+16)
key = key_iv[:32]
iv = key_iv[32:]
aes = AES.new(key, AES.MODE_CBC, iv)
return unpad(aes.decrypt(encrypted[16:]))
password = "some password".encode()
ct_b64 = "U2FsdGVkX1+ATH716DgsfPGjzmvhr+7+pzYfUzR+25u0D7Z5Lw04IJ+LmvPXJMpz"
pt = decrypt(ct_b64, password)
print("pt", pt)
print("pt", decrypt(encrypt(pt, password), password))
Similar code can be found in my answers for Java and PHP.
JavaScript AES encryption in the browser without HTTPS is simple obfuscation and does not provide any real security, because the key must be transmitted alongside the ciphertext.
[UPDATE]:
You should use pycryptodome instead of pycrypto because pycrypto(latest pypi version is 2.6.1) no longer maintained and it has vulnerabilities CVE-2013-7459 and CVE-2018-6594 (CVE warning reported by github). I choose pycryptodomex package here(Cryptodome replace Crypto in code) instead of pycryptodome package to avoid conflict name with Crypto from pycrypto package.

python decrypt a text encrypted in jsencrypt

In a web form the answers (packed in a jsonstring) are encrypted in several steps. First a random key is generated. Second the random key is used for AES encryption of the jsonstring. The random key is encrypted as well. Both are send in the body of a mail.
// Generate Random key
var rand_key = ('0000' + Math.random().toString(36).replace('.', '')).substr(-10);
console.log('rand_key', rand_key)
//var pubkey = "MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBALDjeFwFNhMCjMwcRVVKG1VvfsntEVPR3lNTujJnNk1+iSqZ4Tl5Lwq9GbwO+qlYVwXHNmeqG7rkEhL9uyDIZVECAwEAAQ=="
// rsa_key_public07012016.bin
//var pubkey = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCv8FVei4Q2ehmYsSCv/uODSojIOGHwfQe686S1cEH5i/1mGME5ZzNqyy0d+lhMRD0tr7Sje7JoCEC/XRIZaiKJjpl1+3RXotf/Cx3bd9H7WtitshZB1m38ZZFsrX4oigMpUPFbCefMeBS4hvvNnmtl08lQGhfIXdXeflZsgWRHtQIDAQAB";
// my_pub_key.pem
var pubkey ="MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEA38gtENP9/hpirSCIsPh6CAVm0UmME4XBlPyK8yhwk079EUJpNzlEhu9HKcA/B7Fxo2lNoY9Tb9e+PYtJ6+VOB4+Y6zgGMX7cchYmumKRTbbQ6FNfBE5Q8XnOAUlgC7gNrs0e5lW7JH1kWlK+eTT4TANT7F3US09aXmym+fZaRInbXmJujGnDIbRIIbzr5FE82EeMpw2TqRWV466wz5EeFWSSQ8EqV1pSox8B1ywb6cnB/Vofs2qR9Zf2efi9TMcSGm/ij/p9IZcbLeep9qfGsv29lbLNMfwNwQyH0JU27eAM4tPdirceZPxfD6iiILmKzN253BMoAeQCp6us53CnGQIDAQAB"
// Make form_data a JSON string
var jsonstring = JSON.stringify(form_data);
// Create AES encrypted object
var aes_encrypted_json = CryptoJS.AES.encrypt(jsonstring, rand_key);
// Encrypt rand_key
var encrypt = new JSEncrypt();
//console.log('encrypt obj', encrypt);
encrypt.setPublicKey(pubkey);
var encrypted_rand_key = encrypt.encrypt(rand_key);
//var encrypted = encrypt.encrypt(jsonstring);
console.log('encypted', encrypted_rand_key);
var mail_body = encrypted_rand_key + aes_encrypted_json
console.log('body', mail_body)
var mailto_string = "mailto:info#xyz.com?subject=FORM&body=" + encodeURIComponent(mail_body);
$('#mailtosend').attr('href', mailto_string);
At the recipient mail server side I want to decrypt the random generated key and the jsonstring using a private key using the pycryptodome package.
from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_v1_5
from base64 import *
def decrypt(key, text):
if type(key) == str:
key = key.encode()
if type(text) == str:
text = text.encode()
rsakey = RSA.importKey(key)
rsakey = PKCS1_v1_5.new(rsakey)
d = rsakey.decrypt(text, 'bolloux')
return d
# rand_key am2mhiwwmi
text = "ZvcrluUmZLY3lRRw01W9mQnhMn7zzpIWn1Bo3csM/ZZ0pWY/8H2dCB9fZDi9/cmp0UtIqDXhLd7SIwyxqrFgPcHUuEHlZl0WQcjSty8PjadG2Abulk1XqEQV4u0Gb/bFGDBMcf5tV1G0d4FFcBPE8r8inrxUjSj2CSffVL8gIGq3ZfY5g7t5FOZV8npBCEONgOLKYnzIiHrHUuXWsOaMAqxMFOLd5DTDLKAkyMybDClsLW9ka+CvWd5fnZBCvO2ziehFp7b9PG4QPSnQpdC8jNLGZB2h0FI8YQD6IyUwmVluUbAlPMqwd6A2CBdGCbfbMChaA5R7bJgKkYhPOQTjaQ=="
text = b64decode(text.encode())
with open('my_priv_key.pem', 'rb') as f:
key = f.read()
decrypt(key, text)
I run into a encoding problem. "UnicodeDecodeError: 'ascii' codec can't decode byte 0xf7 in position 1: ordinal not in range(128)" The encoding is complicating the issue beyond my capabilities.
My questions:
1. How can I resolve the encoding problem ?
2. How can I make the decryption work ?
Thanks

The issue is more than likely caused by b64decode(text) returning a str that contains values such as \xf7 and then attempting to .encode() those values within your decrypt function. encode will use the default encoding which in this case is ascii. I would personally remove the calls to encode unless you specifically have a reason you are doing so.

Data Encryption using RSA in javascript

I am using RSA Encryption using JSBN
When I write following code, I am getting error - " 'null' is not an object (evaluating 'this.n.bitLength')" on 92th line(var m = pkcs1pad2(text,(this.n.bitLength()+7)>>3);) in rsa.js file - http://www-cs-students.stanford.edu/~tjw/jsbn/rsa.js
var rsa = new RSAKey();
var pk = "----BEGIN PUBLIC KEY----\r\n"+
"MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCqGKukO1De7zhZj6+H0qtjTkVxwTCpvKe4eCZ0\r\n"+
"FPqri0cb2JZfXJ/DgYSF6vUpwmJG8wVQZKjeGcjDOL5UlsuusFncCzWBQ7RKNUSesmQRMSGkVb1/\r\n"+
"3j+skZ6UtW+5u09lHNsj6tQ51s1SPrCBkedbNf0Tp0GbMJDyR4e9T04ZZwIDAQAB\r\n"+
"----END PUBLIC KEY----";
rsa.setPublic(pk);
var data = rsa.encrypt('hello world');
List of files included :
jsbn.js,
prng4.js,
rng.js,
rsa.js