SFTP implementation question

Sorry Kenny no much progress was made unfortunately,

We have been very busy fixing bugs and extending the functionality of our software.

This month we have had eight releases already.  

Hi Mike,

Appreicated your great effort and looking for the final solution.

Best regards,
Kenny

 

I had another look

I thing what we need to do here is to separate encryption data transfer and description.

Our software can transfer the data using SFTP but encryption and description are limited to PGP via Gpg4win

In my opinion the best way to tackle the challenge is to write the python script (With ChatGpt help)

Here is a basic example which  performs 3 first steps

from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.backends import default_backend
from cryptography.hazmat.primitives import padding
from cryptography.hazmat.primitives import hashes
import os

def generate_nonce():
    return os.urandom(32)

def generate_iv():
    return os.urandom(16)

def pad_data(data):
    padder = padding.PKCS7(128).padder()
    padded_data = padder.update(data)
    padded_data += padder.finalize()
    return padded_data

def encrypt_file(input_file, output_file, key, iv):
    with open(input_file, 'rb') as f:
        data = f.read()
    data = pad_data(data)
    cipher = Cipher(algorithms.AES(key), modes.CBC(iv), backend=default_backend())
    encryptor = cipher.encryptor()
    encrypted_data = encryptor.update(data) + encryptor.finalize()
    with open(output_file, 'wb') as f:
        f.write(encrypted_data)

def main():
    input_file = input("Enter the path of the file to encrypt: ")
    output_file = input_file + '.enc'
    
    nonce = generate_nonce()
    iv = generate_iv()
    
    key = nonce[:32]
    
    encrypt_file(input_file, output_file, key, iv)
    
    print("File encrypted successfully.")

if __name__ == "__main__":
    main()

This script first generates a 32-byte nonce (which acts as the symmetric key) and a 16-byte IV. It then reads the data from the input file, pads it using PKCS7 padding, encrypts it using AES-256 in CBC mode with the provided nonce and IV, and finally writes the encrypted data to a new file with the ".enc" extension.

The script might have some errors (I do not pretend to be an encryption or python expert)

Please accept our apologies for the delay and confusion    
 

Hi Peter,

Thanks for your python script solution and I will try this way. Seems using codeless way for complex requirements is case by case.

Best regards,

Kenny