ESP32 Wi-Fi Manager and System Control Module

This project provides a comprehensive module to manage Wi-Fi connections, system state, and network configurations on an ESP32 microcontroller. It supports a variety of Wi-Fi modes and functionalities, such as connecting to existing networks, creating Access Points (AP), enabling Network Address Translation (NAT) for bridge/repeater mode, and managing system configurations persistently.

Features

• Wi-Fi Station Mode: Connect to existing Wi-Fi networks.
• Access Point Mode: Set up a secured Wi-Fi network with WPA2.
• Bridge/Repeater Mode: Create an Access Point while connecting to another Wi-Fi network using NAT.
• System State Management: Persist system states (e.g., online, offline) to configuration files.
• Encrypted Configuration: Secure sensitive data using AES encryption.
• LED Status Indication: Visual feedback for system states (e.g., idle, connected, error).
• Error Handling: Custom exception handling for Wi-Fi connection errors.
• User Input Masking: Securely mask input for sensitive data, such as passwords.

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Table of Contents

1. Installation
2. Usage
3. Features in Detail
4. Configuration Files
5. Dependencies
6. Contributing
7. License

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Installation

1. Clone this repository onto your ESP32 file system.
2. Ensure all dependencies are installed (see Dependencies).
3. Upload the files to the ESP32 using a compatible IDE (e.g., Thonny, uPyCraft, or rshell).
4. Connect to the ESP32 via a serial terminal to interact with the system.

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Usage

Running the Module

1. Run the script:

   import main
   asyncio.run(main.main_menu())

2. Use the interactive menu to perform actions:

   • 1: Connect to a pre-configured home network.
   • 2: Scan and connect to available networks.
   • 3: Switch to offline mode.
   • 4: Check Wi-Fi status.
   • 5: Start an Access Point.
   • 6: Stop the Access Point.
   • 7: Start Bridge/Repeater mode.
   • 8: Exit the program.

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Features in Detail

1. Wi-Fi Station Mode

• Connect to existing Wi-Fi networks using the connect_to_home or scan_and_connect functions.
• Persistent configuration files store network details securely using AES encryption.

2. Access Point Mode

• Create a secure Wi-Fi network using WPA2.
• Configure the SSID, password, and channel.
• View the Access Point's IP configuration.

3. Bridge/Repeater Mode

• Simultaneously connect to a Wi-Fi network and create an AP for devices to share the connection.
• Enable Network Address Translation (NAT) to bridge devices to the internet.

4. System State Management

• Save system states (e.g., online, offline) to a JSON configuration file.
• Automatically restore the last saved state on startup.

5. Encrypted Configuration

• Use AES encryption for sensitive data such as Wi-Fi passwords.
• Securely decrypt configurations on demand using a master passphrase.

6. LED Status Indication

• Indicate system states visually with an onboard LED:
  • Idle: Blink at 0.25-second intervals.
  • Connected: Blink at 1-second intervals.
  • Error: Quick triple blinks.

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Configuration Files

1. system_config.json

Stores system states persistently:

{
  "state": "offline"
}

2. keys.enc

Encrypted file storing sensitive AES keys. Ensure this file is protected.

3. config.txt.enc

Encrypted Wi-Fi configuration file:

SSID=YourWiFiNetwork
PASSWORD=YourPassword

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Dependencies

This module uses the following libraries:

• uasyncio: Asynchronous I/O for multitasking.
• network: Wi-Fi network interface.
• machine: Hardware control interface for the ESP32.
• ucryptolib: AES encryption for sensitive data.
• ujson: Lightweight JSON parsing for configurations.

Ensure these dependencies are available in your ESP32 MicroPython firmware. Update your firmware if required.

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Example Interaction

After running the module, you’ll see the following menu:

Main Menu:
1: Connect to home network
2: Scan and connect to a network
3: Start offline mode
4: Check Wi-Fi status
5: Start Access Point mode
6: Stop Access Point
7: Start Bridge/Repeater mode
8: Exit Program
Choose an option:

Connecting to Home Network

1. Select option 1.
2. Enter the master passphrase to unlock your encrypted configuration.
3. The system connects to the stored Wi-Fi SSID and displays its IP configuration.

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Contributing

Contributions are welcome! Please follow these steps:

1. Fork the repository.

2. Create a feature branch:

   git checkout -b feature-name
   

3. Commit your changes:

   git commit -m "Add a new feature"
   

4. Push the branch:

   git push origin feature-name
   

5. Submit a pull request.

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License

This project is licensed under the MIT License. See the LICENSE file for details.

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