🔐 PQrypt

Quantum-Resistant Encryption for Everyone

PQrypt is a next-generation encryption application that protects your files and communications against both current and future quantum computer attacks. Available for Desktop (Windows, macOS, Linux) and Android.

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📥 Installation (Pre-built Binaries)

🪟 Windows

1. Go to Releases
2. Download pqrypt-windows.exe
3. Double-click to run (Windows Defender may show a warning - click "More info" → "Run anyway")

🐧 Linux

1. Go to Releases
2. Download pqrypt-linux
3. Open Terminal in the download folder
4. Run:

   chmod +x pqrypt-linux
   ./pqrypt-linux

🍎 macOS (Build Required)

macOS requires building from source due to security restrictions. See Build from Source below.

📱 Android

1. Go to Releases
2. Download PQrypt.apk
3. Open the APK file on your phone
4. Allow installation from unknown sources if prompted
5. Install and open the app

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🛠️ Build from Source

Prerequisites

• Rust: Install from rustup.rs
• Git: For cloning the repository

🍎 macOS (Required)

1. Install Xcode Command Line Tools:

   xcode-select --install

2. Clone and Build:

   git clone https://github.com/GurudattaRK/PQrypt.git
   cd PQrypt/desktop
   cargo build --release

3. Run the App:

   ./target/release/pqrypt

🪟 Windows

1. Install Visual Studio Build Tools:

   • Download from Visual Studio
   • Select "Desktop development with C++"

2. Clone and Build:

   git clone https://github.com/GurudattaRK/PQrypt.git
   cd PQrypt/desktop
   cargo build --release

3. Run the App:

   .\target\release\pqrypt.exe

🐧 Linux

1. Install Dependencies:

   # Ubuntu/Debian
   sudo apt update
   sudo apt install build-essential libxcb-dev libfontconfig1-dev
   
   # Fedora/RHEL
   sudo dnf install gcc-c++ libxcb-devel fontconfig-devel

2. Clone and Build:

   git clone https://github.com/GurudattaRK/PQrypt.git
   cd PQrypt/desktop
   cargo build --release

3. Run the App:

   ./target/release/pqrypt

📱 Android

1. Install Android Studio from developer.android.com

2. Open the Project:

   • Open Android Studio
   • Select "Open an existing project"
   • Navigate to PQrypt/android/

3. Install SDK Components:

   • Open SDK Manager (Tools → SDK Manager)
   • Install Android SDK Platform 34
   • Install NDK version 25 or higher
   • Install CMake 3.22.1

4. Build and Install:

   • Connect your Android device via USB (enable Developer Mode)
   • Click the green "Run" button in Android Studio
   • Or use command line:

     cd android
     ./gradlew installDebug

   • Or if you want to build an APK in debug mode, use command line:

     cd android
     ./gradlew assembleDebug

   • Or if you want to build an APK in release mode (for release mnode you'll have to sign it by setting up a signing key in android studio), use command line:

     cd android
     ./gradlew assembleRelease

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🔒 Cryptographic Architecture

PQrypt implements a 9-algorithm hybrid cryptographic system combining classical and post-quantum algorithms for maximum security:

Layer 1: Post-Quantum Key Exchange

1. ML-KEM-1024 (FIPS 203) - NIST-standardized lattice-based key encapsulation
2. X448 - Elliptic curve Diffie-Hellman for classical security
3. HQC-256 - Code-based post-quantum algorithm
4. SecP521R1 - NIST elliptic curve for additional classical strength

Layer 2: Triple-Layer Symmetric Encryption

5. Threefish-1024 - 1024-bit block cipher (outermost layer)
6. Serpent-256 - AES finalist cipher (middle layer)
7. AES-256-GCM - NIST standard with authentication (innermost layer)

Layer 3: Key Derivation & Authentication

8. Argon2id - Memory-hard password hashing (winner of Password Hashing Competition)
9. ML-DSA (FIPS 205) - Post-quantum digital signatures for authentication

How They Work Together

┌─────────────────────────────────────────────────────┐
│  Key Exchange: ML-KEM ⊕ X448 + HQC ⊕ P521           │
│  (Post-quantum + Classical hybrid)                  │
└──────────────────────┬──────────────────────────────┘
                       ↓
              ┌────────────────┐
              │  Argon2id KDF  │ ← Password derivation
              └────────┬───────┘
                       ↓
        ┌──────────────────────────────┐
        │   Triple Encryption Layers   │
        │  Threefish → Serpent → AES   │
        │  (Each layer adds security)  │
        └──────────────┬───────────────┘
                       ↓
              ┌────────────────┐
              │  ML-DSA Sign   │ ← Authentication
              └────────────────┘

This architecture ensures:

• Quantum Resistance: Even if quantum computers break one algorithm, others remain secure
• Defense in Depth: Multiple encryption layers protect against cryptanalysis
• Forward Secrecy: Each session uses unique ephemeral keys
• Authentication: Digital signatures prevent tampering

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✨ Features

• 🛡️ Post-Quantum Secure: Protected against quantum computer attacks
• 📁 File Encryption: Encrypt any file with password or key file
• 💬 Secure Messaging: Send encrypted text/files between devices
• 🔑 Password Vault: Store passwords with quantum-resistant encryption
• 📱 Cross-Platform: Works on Android, Windows, macOS, and Linux
• 🔄 Key Exchange: Secure key sharing via Bluetooth or manual transfer
• 🎯 Zero Knowledge: Your keys never leave your device

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🏗️ Architecture

• Desktop Application (desktop/): Cross-platform GUI built with Rust and Slint UI framework
• Android Application (android/): Native Android app with Kotlin/Java frontend and optimized C++/Rust backend

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⚠️ Disclaimer

This software is provided "as is" without warranty. While we use industry-standard algorithms and best practices, no encryption or security is 100% unbreakable. Always:

• Keep backups of important data
• Use strong, unique passwords
• Keep your software updated
• Don't share your encryption keys

🔗 Links

• Rust Documentation
• Slint UI Framework
• Android NDK Guide
• Post-Quantum Cryptography