Project 3 – TRNG-PassGen: A Hardware-Based Cryptographically Secure Password Generator
July 16, 2025
Developed as a final team project for the ‘Digital Electronics’ track of an international educational exchange at the AIEO “Phystech-Lyceum” of Natural Sciences and Mathematics named after P.L. Kapitza, this project is a complete system for generating secure passwords. It’s built on true physical randomness to address the vulnerabilities of software-based pseudo-random number generators (PRNGs), particularly in the face of emerging quantum computing threats.
The system demonstrates a full-stack approach to a real-world security problem, spanning from low-level hardware interaction and embedded C++ programming to high-level, secure network communication and modern desktop application development in Rust.
System Architecture
The project consists of two primary components that work together to create a seamless and secure user experience.
1. Embedded TRNG Device (C++ / ESP32)
The core of the system is a custom-built hardware device that generates truly random data.
- 🌪️ Entropy Harvesting: Gathers true entropy from unpredictable physical sources, including motion data from an MPU-6050 accelerometer/gyroscope and electronic noise from oscillator jitter.
- ⚙️ Random Number Generation: Utilizes a motion-controlled ‘gated counter’ on an ESP32 microcontroller to process the raw entropy into random bytes.
- 🔒 On-Device Encryption: Secures the generated 128-bit random key on the device itself using AES-128-CBC encryption via the
mbedtlslibrary. - 📡 Secure Communication: Hosts its own Wi-Fi Access Point and a TCP server for secure data transmission to the client application. It also features a small OLED screen for a user interface.
2. Desktop Client Application (Rust)
A cross-platform desktop application provides the user interface and final password generation.
- 🦀 Modern & Asynchronous: Developed in Rust with an asynchronous graphical user interface (GUI) using the Iced and Tokio frameworks.
- 🔗 Secure Connection & Decryption: Connects directly to the hardware device’s TCP server, receives the encrypted data, and decrypts the AES key.
- 📱 Password Generation & Display: Uses the decrypted random key to generate a final, secure password. It displays the password along with a scannable QR code for easy use on mobile devices.
- 🎨 Custom UI & Remote Control: Features a full remote control for the hardware device and a custom user interface with switchable light and dark themes.
Technologies & Skills
- Languages: C++, Rust, C
- Hardware & Embedded: ESP32 Microcontrollers, Digital Circuit Design, Soldering, 3D Printing, EasyEDA
- Security & Networking: Cryptography, Encryption (AES), TCP/IP Networking
- Software & Design: UI/UX Design
- Professional: Teamwork, Communication, Leadership