Quantum-Safe Encryption Demo

A frontend web application demonstrating post-quantum cryptography using Classic McEliece combined with AES-GCM hybrid encryption.

Overview

This demo showcases quantum-resistant asymmetric encryption using:

• Classic McEliece (8192128) - A key encapsulation mechanism (KEM) providing ~256-bit post-quantum security
• AES-GCM - Symmetric encryption using the Web Crypto API for actual message encryption

How It Works

McEliece is a KEM (Key Encapsulation Mechanism), not a direct encryption algorithm. This demo uses a hybrid encryption scheme combining post-quantum key exchange with symmetric encryption:

flowchart TB
    subgraph keygen["🔑 Key Generation"]
        direction LR
        KG[McEliece KeyPair] --> PK["📤 Public Key<br/><i>~1.3 MB</i>"]
        KG --> SK["📥 Private Key<br/><i>~14 KB</i>"]
    end

    subgraph encrypt["🔒 Encryption"]
        direction TB
        PK2["Recipient's<br/>Public Key"] --> KEM["McEliece<br/>Encapsulate"]
        KEM --> SECRET1["Shared Secret<br/><i>32 bytes</i>"]
        KEM --> KEMCT["KEM Ciphertext<br/><i>~240 bytes</i>"]
        SECRET1 --> AES["AES-GCM<br/>Encrypt"]
        MSG["Plaintext<br/>Message"] --> AES
        IV["Random IV<br/><i>12 bytes</i>"] --> AES
        AES --> AESCT["Encrypted<br/>Data"]
        KEMCT --> PKG["Package"]
        IV --> PKG
        AESCT --> PKG
        PKG --> FINAL["📦 Final Ciphertext<br/><i>Base64 encoded</i>"]
    end

    subgraph decrypt["🔓 Decryption"]
        direction TB
        CT["📦 Ciphertext"] --> UNPKG["Unpackage"]
        UNPKG --> KEMCT2["KEM<br/>Ciphertext"]
        UNPKG --> IV2["IV"]
        UNPKG --> AESCT2["Encrypted<br/>Data"]
        KEMCT2 --> KEMDEC["McEliece<br/>Decapsulate"]
        SK2["Your<br/>Private Key"] --> KEMDEC
        KEMDEC --> SECRET2["Shared Secret<br/><i>32 bytes</i>"]
        SECRET2 --> AESDEC["AES-GCM<br/>Decrypt"]
        IV2 --> AESDEC
        AESCT2 --> AESDEC
        AESDEC --> PLAIN["✉️ Plaintext<br/>Message"]
    end

    PK -.->|"share publicly"| encrypt
    SK -.->|"keep secret"| decrypt
    encrypt -->|"send securely"| decrypt

    style keygen stroke:#19FB9B,stroke-width:2px
    style encrypt stroke:#19FB9B,stroke-width:2px
    style decrypt stroke:#19FB9B,stroke-width:2px
    style SECRET1 fill:#19FB9B,color:#000
    style SECRET2 fill:#19FB9B,color:#000

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Step-by-Step

1. Encryption:

   • McEliece KEM generates a random shared secret + KEM ciphertext from the recipient's public key
   • AES-GCM encrypts the plaintext using the shared secret as the key
   • The KEM ciphertext, IV, and encrypted data are packaged together

2. Decryption:

   • Unpackage the ciphertext components
   • McEliece KEM recovers the shared secret from the KEM ciphertext using the private key
   • AES-GCM decrypts the data using the recovered shared secret

Features

• Key Generation - Generate McEliece keypairs (public key ~1.3 MB, private key ~14 KB)
• Encrypt - Encrypt messages to a recipient's public key
• Decrypt - Decrypt messages using your private key
• File Import/Export - Download and load keys and ciphertexts

Prerequisites

• Node.js (v18 or higher recommended)
• npm (comes with Node.js)

Installation

1. Clone the repository:

git clone <repository-url>
cd pqdemo

2. Install dependencies:

npm install

Running the Application

Development Server

Start the Vite development server with hot reload:

npm run dev

The app will be available at http://localhost:5173

Production Build

Build the application for production:

npm run build

This creates an optimized build in the dist/ directory.

Preview Production Build

Preview the production build locally:

npm run preview

Project Structure

pqdemo/
├── index.html      # Main HTML file
├── app.js          # Application logic (key gen, encrypt, decrypt)
├── style.css       # idOS-branded styles
├── package.json    # Dependencies and scripts
├── vite.config.js  # Vite configuration (if present)
└── README.md       # This file

Dependencies

Package	Version	Description
mceliece	^5.0.0	Classic McEliece post-quantum KEM
vite	^6.0.0	Frontend build tool (dev dependency)

Security Considerations

⚠️ This is a demonstration application.

For production use:

• Implement proper key management and secure storage
• Use secure channels for key exchange
• Consider key rotation policies
• Audit cryptographic implementation
• Never expose private keys

Technical Notes

• Key Sizes: McEliece public keys are large (~1.3 MB) due to the algorithm's design
• Performance: Key generation takes several seconds due to the computational complexity
• Browser Support: Requires browsers with Web Crypto API support (all modern browsers)

License

MIT

Credits

• pqcrypto.js - Post-quantum cryptography library
• idOS Network - Brand design inspiration