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Object type <class 'tuple'> cannot be passed to C code when encrypting file in django

so i want to encrypt file .txt with keyword i was input. but i got error message
Object type <class 'tuple'> cannot be passed to C code
my problem is with this code:
aes = AES.new(key.encode('utf8'), AES.MODE_CTR, counter=ctr)
if i add encode to ctr, then i got error message 'dict' object has no attribute 'encode'
if i remove don't add any encode to key and ctr, then i got error message Object type <class 'str'> cannot be passed to C code
can someone please help me to fix it? i was using django to encrypt with AES 128 with method CTR. or maybe someone can give me example aes encryption with another method but can be run in django. here's my full function code:
# AES supports multiple key sizes: 16 (AES128), 24 (AES192), or 32 (AES256).
key_bytes = 16
# Takes as input a 32-byte key and an arbitrary-length plaintext and returns a
# pair (iv, ciphtertext). "iv" stands for initialization vector.
def encrypt(key, testpass):
assert len(key) == key_bytes
print(testpass)
print(key)
# Choose a random, 16-byte IV.
iv = Random.new().read(AES.block_size)
# Convert the IV to a Python integer.
iv_int = int(binascii.hexlify(iv), 16)
# Create a new Counter object with IV = iv_int.
ctr = Counter.new(AES.block_size * 8, initial_value=iv_int)
print(ctr)
# Create AES-CTR cipher.
aes = AES.new(key.encode('utf8'), AES.MODE_CTR, counter=ctr)
# Encrypt and return IV and ciphertext.
ciphertext = aes.encrypt(testpass)
print(iv)
print(ciphertext)
return (iv, ciphertext)
here's how i called that function:
testpass = Audio_store.objects.all().values_list('password').last()
enkripsi = encrypt("testingtesting11", testpass)
when i print testpass, it contains ('testpass_3kEMV2T.txt',)
but when i print testpass.encode("utf-8"), it shows nothing

Your test data is ('testpass_3kEMV2T.txt',), you need to pull out the element from the tuple and pass it in as bytes to your encrypt method, because the AES.encrypt method requires bytes | bytearray | memoryview as its argument. Here's a version of your encrypt that determines if the argument you pass it is a str and encodes it to bytes if so (but it doesn't check if it's otherwise bytes, I leave that as an exercise for you if you want more stringent checking).
import binascii
from Crypto.Cipher import AES
from Crypto.Util import Counter
from Crypto import Random
key_bytes = 16
# here's a rudimentary change that accepts bytes or
# str
def encrypt(key, plaintext):
if isinstance(plaintext, str):
plaintext = plaintext.encode("utf-8")
assert len(key) == key_bytes
# Choose a random, 16-byte IV.
iv = Random.new().read(AES.block_size)
# Convert the IV to a Python integer.
iv_int = int(binascii.hexlify(iv), 16)
# Create a new Counter object with IV = iv_int.
ctr = Counter.new(AES.block_size * 8, initial_value=iv_int)
print(ctr)
# Create AES-CTR cipher.
aes = AES.new(key.encode('utf8'), AES.MODE_CTR, counter=ctr)
# Encrypt and return IV and ciphertext.
ciphertext = aes.encrypt(plaintext)
return (iv, ciphertext)
# for now, since you're getting your data from the db which is a 1-tuple, you have to pull out the first elem
testpass = ('testpass_3kEMV2T.txt',)
print(encrypt("a"*16, testpass[0]))
Output:
{'counter_len': 16, 'prefix': b'', 'suffix': b'', 'initial_value': 302861312392273214314458272471454024973, 'little_endian': False}
(b'\xe3\xd8\xf7\x90\xcd\x96m\xcb\xa5g)\xd1\xda\xc3\x85\r', b'-F)\x83\x9a\xf9\xe1\xc3\xfb\xfa_<^\x1c:q\x07\xa1#\xbb')

Encryption in python and decryption in vb.net not working

I have this requirement where I need to encrypt a dictionary in python using password based AES256 encryption. I was only given a sample vb.net project by my boss to take reference from regarding the steps that I need to follow for encryption but I am not really aware of how vb.net works. I have converted as much code from vb.net to python as much I could but still the output that my code produces is different from the vb.net project. Can someone please explain what exactly am I missing out on due to which the encryption output of my python program is different than the encryption output of the vb.net program? Thanks in advance!
Here is the vb.net code
Imports System.IO
Imports System.Security.Cryptography
Imports System.Text
Imports System.Web.Script.Serialization
Imports System.Net
Imports System.Security.Cryptography.X509Certificates
Imports System.Net.Security
Public Class Form1
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
loginrequest()
End Sub
Private Sub loginrequest()
Dim lobjLogin As New loginrequest
lobjLogin.jsonProperty1 = "jsonProperty1"
lobjLogin.jsonProperty2 = "jsonProperty2"
lobjLogin.jsonProperty3 = "jsonProperty3"
lobjLogin.jsonProperty4 = "jsonProperty4"
Dim lRequestJson As String = ""
lRequestJson = (New JavaScriptSerializer()).Serialize(lobjLogin)
Dim lchecksum As String = EncryptText(lRequestJson, "key")
End Sub
Public Function EncryptText(pInput As String, password As String) As String
Dim bytesToBeEncrypted As Byte() = Encoding.UTF8.GetBytes(GenerateSHA256String(pInput))
Dim passwordBytes As Byte() = Encoding.UTF8.GetBytes(password)
passwordBytes = SHA256.Create().ComputeHash(passwordBytes)
Dim bytesEncrypted As Byte() = AES_Encrypt(bytesToBeEncrypted, passwordBytes)
Dim result As String = Convert.ToBase64String(bytesEncrypted)
Return result
End Function
Private Function AES_Encrypt(bytesToBeEncrypted As Byte(), passwordBytes As Byte()) As Byte()
Dim encryptedBytes As Byte() = Nothing
Dim saltBytes As Byte() = New Byte() {1, 2, 3, 4, 5, 6, _
7, 8}
Using ms As New MemoryStream()
Using AES As New RijndaelManaged()
AES.KeySize = 256
AES.BlockSize = 128
Dim key = New Rfc2898DeriveBytes(passwordBytes, saltBytes, 1000)
AES.Key = key.GetBytes(AES.KeySize / 8)
AES.IV = key.GetBytes(AES.BlockSize / 8)
AES.Mode = CipherMode.CBC
Using cs = New CryptoStream(ms, AES.CreateEncryptor(), CryptoStreamMode.Write)
cs.Write(bytesToBeEncrypted, 0, bytesToBeEncrypted.Length)
cs.Close()
End Using
encryptedBytes = ms.ToArray()
End Using
End Using
Return encryptedBytes
End Function
Private Function GenerateSHA256String(ByVal inputString) As String
Dim sha256 As SHA256 = SHA256Managed.Create()
Dim bytes As Byte() = Encoding.UTF8.GetBytes(inputString)
Dim hash As Byte() = sha256.ComputeHash(bytes)
Dim stringBuilder As New StringBuilder()
For i As Integer = 0 To hash.Length - 1
stringBuilder.Append(hash(i).ToString("X2"))
Next
Return stringBuilder.ToString()
End Function
End Class
Public Class loginrequest
Public Property jsonProperty1 As String
Public Property jsonProperty2 As String
Public Property jsonProperty3 As String
Public Property jsonProperty4 As String
End Class
Here is the corresponding python code that I wrote
import base64
from Crypto.Cipher import AES
from Crypto.Protocol.KDF import PBKDF2
from Crypto.Util.Padding import pad
import hashlib, json
payload = {
"jsonProperty1": "jsonProperty1",
"jsonProperty2": "jsonProperty2",
"jsonProperty3": "jsonProperty3",
"jsonProperty4": "jsonProperty4",
}
payload = json.dumps(payload)
bytesToBeEncrypted = hashlib.sha256(payload.encode("utf-8")).hexdigest()
class AESCipher(object):
def __init__(self, key, interactions=1000):
self.bs = AES.block_size
self.key = hashlib.sha256(key.encode("utf-8")).hexdigest()
self.interactions = interactions
def pkcs7padding(self, data, block_size=16):
if type(data) != bytearray and type(data) != bytes:
raise TypeError("Only support bytearray/bytes !")
pl = block_size - (len(data) % block_size)
return data + bytearray([pl for i in range(pl)])
def encrypt(self, raw):
import os
raw = "".join([x.upper() for x in bytesToBeEncrypted])
keyiv = PBKDF2(self.key, os.urandom(8), 48, self.interactions)
key = keyiv[:32]
iv = keyiv[32:48]
cipher = AES.new(key, AES.MODE_CBC, iv)
encoded = raw.encode("utf-8")
encodedpad = self.pkcs7padding(encoded)
ct = cipher.encrypt((encodedpad))
cip = base64.b64encode(ct)
print(cip, len(cip))
enc = AESCipher("key")
dec = enc.encrypt(bytesToBeEncrypted)
Please note that I took some reference from some other threads as well regarding my python code because encryption is a new concept for me.
P.S. I also found out that the vb.net code is using .toString("X2") to generate a hexadecimal string in uppercase but unfortunately, I was not able to find the corresponding equivalent in python for the same. Could that be a problem?

Implementing PKCS7 padding in python for a C# script

I have this encrypt with AES function in python:
def encrypt_text(self):
raw = self.PKCS7_padding()
iv = Random.new().read(self.block_size)
cipher = AES.new(self.key, AES.MODE_CBC, iv)
encrypted = base64.b64encode(iv + cipher.encrypt(raw))
return encrypted
And then padding it with:
def PKCS7_padding(self):
return self.text+chr(16-len(self.text)%16)*(16-len(self.text)%16)
But when I send it to this c# function
public static string DecryptString(string key, string cipherText)
{
byte[] iv = new byte[16];
byte[] buffer = Convert.FromBase64String(cipherText);
using (Aes aes = Aes.Create())
{
aes.Key = Convert.FromBase64String(key);
aes.IV = iv;
ICryptoTransform decryptor = aes.CreateDecryptor(aes.Key, aes.IV);
using (MemoryStream memoryStream = new MemoryStream(buffer))
{
using (CryptoStream cryptoStream = new CryptoStream((Stream)memoryStream, decryptor, CryptoStreamMode.Read))
{
using (StreamReader streamReader = new StreamReader((Stream)cryptoStream))
{
return streamReader.ReadToEnd();
}
}
}
}
}
Say i send "hello world"
I get a weird mix of the string i sent plus random non pritable characters. EX: "�Ȯ�Ŗf�"��Xhello world"
The key is generated as follows:
key = base64.b64encode(os.urandom(32))
return key.decode()
I do not get any errors but weird text any ideas Thanks! If you have any questions please feel free to ask

In the Python code, a random IV is generated and concatenated with the ciphertext. However, in the C# code, the separation of IV and ciphertext is missing. Instead, a zero IV is applied and the concatenation of IV and ciphertext is decrypted, which causes the problem.
The separation of IV and ciphertext can be added to the C# code e.g. as follows:
byte[] buffer = ...
byte[] ct = new byte[buffer.Length - iv.Length];
Buffer.BlockCopy(buffer, 0, iv, 0, iv.Length);
Buffer.BlockCopy(buffer, iv.Length, ct, 0, ct.Length);
buffer = ct;
using ...
Note that PyCryptodome supports padding in a dedicated module: Crypto.Util.Padding.
Also, in the Python code the Base64 encoded key is nowhere Base64 decoded (but maybe the corresponding code was just not posted).

Decrypt Kamstrup WMBUS in Python

I have a Kamstrup WMbus water meter sending out frames like this:
21442D2C529027581B168D2814900939201F0775C6452FBBAC155B46A546035219D51AB8
I am trying to decrypt this in Python.
Breaking the frame up I have the following values:
Key 16ce383ebc0790e928215525cd4f7abf
Input IV 2D2C529027581B162890093920000000
Input Data 1F0775C6452FBBAC155B46A546035219D5
Pasting this into http://www.cryptogrium.com/aes-ctr.html results in a valid decrypted frame:
bbe57934ddc46a71004400000044000000
I have tried both PyCrypto and PyCryptodome but neither gives the same correct answer than cryptogrium.com.
from Cryptodome.Cipher import AES
# ctr = Crypto.Util.Counter.new(128, initial_value=int("0000002039099028161B582790522C2D", 16))
# cipher = Crypto.Cipher.AES.new(ecryptionKey, Crypto.Cipher.AES.MODE_CTR, counter=ctr)
# secret = Secret()
spec = AES.new(ecryptionKey, AES.MODE_CTR, iv=inputIV)
dataDec = cipher.decrypt(data)
The first commented out approach runs but gives the wrong result.
The second one stops with the error:
TypeError: Invalid parameters for CTR mode: {'iv': bytearray(b"-,R\x90\'X\x1b\x16(\x90\t9 \x00\x00\x00")}
In C# we are using the following which works:
IBufferedCipher cipher = CipherUtilities.GetCipher("AES/CTR/NoPadding");
ParametersWithIV ivAndKey = new ParametersWithIV(new KeyParameter(keyBytes), inputIVBytes);
cipher.Init(false, ivAndKey);
...
int length1 = cipher.ProcessBytes(data, 0, data.Length, outBuf, 0);
int length2 = cipher.DoFinal(outBuf, length1);
...
I am confused because C# uses the parameters I have: key, data, IV
But Python expects: key, data, counter
Does anyone have an example how I can decrypt this in Python3? Or maybe explain how I should use the IV to set up the counter for AES-CNT?

In the end one of the examples from https://www.programcreek.com/python/example/87998/Crypto.Cipher.AES.MODE_CTR put me on the right track. After fixing a couple of typos in my code it worked correctly.
def kamstrupDecrypt(meterSerial, frame, payload):
inputIV = getInputIV(frame)
print("IV:", binascii.hexlify(inputIV))
ecryptionKey = getEncryptionKey(meterSerial)
print("Key:", binascii.hexlify(ecryptionKey))
counter = Counter.new(128, initial_value = bytes_to_long(inputIV))
cipher = AES.new(ecryptionKey, AES.MODE_CTR, counter=counter)
payloadDec = cipher.decrypt(payload)
print("Decrypted: ", binascii.hexlify(payloadDec))
return payloadDec

Python AES.MODE_CTR does not decrypt as expected

I am trying to rewrite a node.js decoding function in python
this is the function I am trying to rewrite
module.exports.decrypt = function (data, key, iv, hmacKey) {
iv = iv.slice(0, 16)
var decipherer = crypto.createDecipheriv('aes-128-ctr', key, iv)
var hmac
if (hmacKey) {
hmac = crypto.createHmac('sha1', hmacKey).update(data).digest()
}
return {
data: decipherer.update(data),
hmac: hmac
}
}
the key parameter is generated by crypto.pbkdf2Sync function of node's standard library.
What I implemented in python is
from Crypto.Cipher import AES
from Crypto.Util import Counter
def decrypt(data, key, iv, hmac=None):
iv = iv[:16]
ctr = Counter.new(128)
cipher = AES.new(key, mode=AES.MODE_CTR, IV=iv, counter=ctr)
return cipher.decrypt(data)
I provided the python decrypt function the same same data that the js function receives.
since the data and key, iv params that the js function expects are binary buffers, I copied them to the python code as hex strings and then used binascii.unhexlify in the python code before passing them to the ecrypt python function.
so the arguments that I am providing to both functions are (hex)
data 972acf88c5d7
key 129b6e542600889a75ec7659d9dc23df
iv 31323331323331323331323331323331323331323331313233313233313233313233
The python function returns gibberish.
can anyone help?
thanks!