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Crypto hmac conversion from Python to Javascript

I'm trying to convert the following function from Python to Javascript.
Currently concentrating on the generation of the signature.
def prepare_url(self, segments, params={}):
if self.token is not None:
sig = hmac.new(self.token.key.encode(), digestmod=hashlib.sha1)
sig.update(self.method.lower().encode())
sig.update(self.service.lower().encode())
ts = self.get_timestamp(self.token.server_offset)
sig.update(ts.encode())
params["timestamp"] = ts
sig.update(self.token.identifier.lower().encode())
params["signature-method"] = "auth"
params["signature-version"] = self.version
params["signature"] = base64.standard_b64encode(sig.digest())
self.url = "%s/%s/%d/" % (self.base_path, self.service, self.version)
self.url += "/".join([urllib.parse.quote(s) for s in segments])
if params:
self.url += "?%s" % urllib.parse.urlencode(params)
In Javascript I'm using the crypto library and have the following code:
import crypto from 'crypto';
const KEY = '5d016f32-452f-4b9b-8e81-641e14d4d98c';
const METHOD = 'get';
const SERVICE = 'data';
const date = (new Date()).toISOString().slice(0, 19);
const encoded = crypto.createHash('sha1')
.update(KEY)
.update(METHOD.toLowerCase())
.update(SERVICE.toLowerCase())
.update(date)
.digest('hex');
console.log(encoded);
const baseEncoded = btoa(encoded);
console.log(baseEncoded);
However the end codes are not comparable.
Python generates using the given inputs: b'oV4RJ6pAz+hxZsxeQthx8gZrhAY='
Javascript generates: YTZjMmIyYjQzOGEwZGUxZTU1YTNjMWVlYjA3MTA3NTFmODc0MDM3ZQ==
I googled around but could not find what to change to make this work.
In python the digest is hashlib.sha1, this is not available in crypto.
Any pointers?
Below are the codes Python generates at each of the update steps.
-----> key: b'bnAcIlriz+t4hTQLBrnjI1aeXBI='
-----> method: b'rc1Y6wKZo8pDKHmhjVNDkhcVNKM='
-----> Service: b'/urBh6Yqk6QI39JhYtSMI9P9QS8='
-----> Time: 5d016f32-452f-4b9b-8e81-641e14d4d98c
-----> Identifier: b'oV4RJ6pAz+hxZsxeQthx8gZrhAY='
-----> FINAL: b'oV4RJ6pAz+hxZsxeQthx8gZrhAY='
Solution:
const encoded = crypto.createHmac('sha1', key)
.update(METHOD.toLowerCase())
.update(SERVICE.toLowerCase())
.update(date)
.update(identify)
.digest('base64');

Based on the feedback from #PresidentJamesK.Polk I was able to figure this out.
const encoded = crypto.createHmac('sha1', key)
.update(METHOD.toLowerCase())
.update(SERVICE.toLowerCase())
.update(date)
.update(identify)
.digest('base64');

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"

Javascript getParams breaking JSON

I have a URL with JSON in it.
This is the URL:
http://localhost:1234/asset/view-details.action?id=5&assetJson=%%7B%0A%20%20%22assetDesc%22%3A%20%22AMERICAN%20HARDWARE%20%26%20TOOLS%22%0A%7D
The JSON file can be retrieved with:
const assetJson = getParams.get('assetJson');
const assetDetail = JSON.parse(assetJson);
assetDetail should be equal to:
{
"assetDesc": "AMERICAN HARDWARE & TOOLS"
}
In JavaScript, every time I try getParams.get('assetJson'), I get this error "Unexpected end of JSON input". It's because the returned value is cut off at the ampersand( & ). I end up with:
{
"assetDesc": "AMERICAN HARDWARE
& TOOLS" } is completely cut off.
Is there a way to fix this? I appreciate any help you can give.

You can always use URLSearchParams and it's get function along with JSON.parse.
The substring(1) that I'm using exists to get rid of a % sign that is coming up before the JSON start {.
var str = "http://localhost:1234/asset/view-details.action?id=5&assetJson=%%7B%0A%20%20%22assetDesc%22%3A%20%22AMERICAN%20HARDWARE%20%26%20TOOLS%22%0A%7D";
const urlParams = new URLSearchParams(str);
myParam = urlParams.get('assetJson').substring(1);
myParam = JSON.parse(myParam)
console.log(myParam.assetDesc)

This is how I solved it.
const parseResult = new DOMParser().parseFromString(window.location.search, 'text/html');
// replace "&" with it's URL encoding
const parsed = parseResult.documentElement.textContent.replace('%20&', '%20%26');
const urlParams = new URLSearchParams(parsed);
const assetJson = urlParams.get('assetJson');
const assetDetail = JSON.parse(assetJson);

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.

Progressive HMAC SHA256 in Objective-C

I need to generate a hash using HMAC SHA256. I am using the following code in JavaScript. I need an equivalent code in Objective-C.
function serialize( obj ) {
return Object.keys(obj).reduce(function(a,k){a.push(k+'='+encodeURIComponent(obj[k]));return a},[]).join('&')
}
var query = {
Action : 'MyAction',
SignatureMethod : 'HmacSHA256',
};
var hmac = CryptoJS.algo.HMAC.create(CryptoJS.algo.SHA256, 'MYVALUE');
var queryString = ['POST', 'm.service.it', '/api/v2', serialize(sorted)].join('\n');
hmac.update(queryString);
query.Signature = CryptoJS.enc.Base64.stringify(hmac.finalize());
How implement this in Objective-C?

HMAC-SHA256 sample code:
+ (NSData *)hmacSha256:(NSData *)dataIn
key:(NSData *)key
{
NSMutableData *macOut = [NSMutableData dataWithLength:CC_SHA256_DIGEST_LENGTH];
CCHmac( kCCHmacAlgSHA256,
key.bytes,
key.length,
dataIn.bytes,
dataIn.length,
macOut.mutableBytes);
return macOut;
}
Notes:
Add Security.framework to the project
Common Crypto must be included:
#import <CommonCrypto/CommonCrypto.h>
This is data in and out, add any conversions to desired representations before and after.
Conversions could be string to data on input and data to Base64 on output:
NSData *data = [#"string" dataUsingEncoding:NSUTF8StringEncoding];
NSString *string = [data base64EncodedStringWithOptions:0];