CipherNet - Your Secure Gateway to Private Networks

Overview

CipherNet (A fork of Simple VPN) is a robust and lightweight VPN implementation designed to secure communications between multiple clients and a server. Leveraging a custom VPN interface (tun0), CipherNet encrypts data using the AES-256-CFB algorithm, ensuring that your network communications remain confidential and protected from prying eyes.

Project Structure

• setup_vpn.sh: A shell script to start the VPN server or client.
• teardown_vpn.sh: A shell script to stop the VPN server and client, and clean up any configurations.
• vpn.c: The main C source code file that implements the VPN functionality.
• vpndemo: The compiled executable from vpn.c.

Features

• Multi-Client Support: Allows multiple clients to connect securely to a single server.
• Strong Encryption: Uses AES-256-CFB to safeguard your data.
• Flexible Configuration: Server and client IP addresses can be configured dynamically at runtime.
• Easy Setup and Teardown: Includes scripts to automate the setup and teardown process.

Prerequisites

• Operating System: Linux (with TUN/TAP support)
• Compiler: GCC
• Dependencies: OpenSSL library (for encryption)

Installation

1. Clone the Repository:

   git clone https://github.com/iamkadoski/CipherNet.git
   cd CipherNet
   gcc -o <APP_NAME> ciphervpn.c -lcrypto -lssl -pthread 
    

2. Verify the Files:Ensure the following files are in the CipherNet directory:

   • setup_vpn.sh

   • teardown_vpn.sh

   • ciphervpn.c

Usage

Starting the VPN

 sudo ./setup_vpn.sh <APP_NAME> <SERVER|CLIENT> <AES_KEY> <SERVER_IP> 
  
 sudo ./setup_vpn.sh <APP_NAME> CLIENT <AES_KEY> <SERVER_IP> 

Stopping the VPN

Use the following command to stop the VPN server and client, and clean up:

sudo ./teardown_vpn.sh  

Example Commands

sudo ./setup_vpn.sh ciper SERVER mysecurekey1234567890 192.168.1.1    
sudo ./setup_vpn.sh cipher CLIENT mysecurekey1234567890 192.168.1.1    
sudo ./teardown_vpn.sh

Security Considerations

• Encryption: CipherNet uses AES-256-CFB encryption, which is highly secure. Ensure that the AES key and initialization vector (IV) are managed securely and are not exposed to unauthorized parties.

• OpenSSL Version: CipherNet relies on OpenSSL for encryption. Regularly update OpenSSL to mitigate any vulnerabilities.

Troubleshooting

• Compilation Errors: Ensure that the OpenSSL library is installed. If you encounter deprecation warnings with OpenSSL 3.0+, refer to the updated aes_encrypt_decrypt function in the vpn.c file.

• Connection Issues: Verify that the server IP is correctly configured and that there are no firewall rules blocking the connection.

Contributing

If you find bugs or have suggestions for improvements, feel free to submit issues or pull requests on the project repository.