entropyX

A cryptographically secure password generator with uniqueness enforcement via SHA-256 hashing and Supabase storage. Available as both a Python CLI script and a cross-browser extension (Chrome + Firefox).

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How It Works

OS entropy → password → SHA-256 → Supabase check → store if unique → return

1. Password is generated using OS entropy (os.urandom / crypto.getRandomValues)
2. Password is hashed with SHA-256
3. Hash is checked against Supabase — if it exists, regenerate
4. If unique, only the hash is stored — plaintext never touches the database

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Project Structure

securepass/
├── generate_password.py        # Python CLI script
├── extension/
│   ├── manifest.json           # Chrome + Firefox MV3
│   ├── popup.html              # Extension UI
│   ├── popup.js                # Extension logic
│   └── icons/
│       └── icon48.png
└── README.md

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Setup

Supabase

Create a table in your Supabase project via the SQL Editor:

CREATE TABLE passwords (
    id         BIGSERIAL PRIMARY KEY,
    hash       TEXT      NOT NULL UNIQUE,
    created_at TIMESTAMPTZ DEFAULT now()
);

CREATE UNIQUE INDEX idx_passwords_hash ON passwords (hash);

Then grab your Project URL and Anon Key from Project Settings → API.

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Python Script

pip install supabase

Set your credentials at the top of generate_password.py:

SUPABASE_URL = "https://your-project.supabase.co"
SUPABASE_KEY = "your-anon-key"

Run it:

python3 generate_password.py

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Browser Extension

Set your credentials at the top of extension/popup.js:

const SUPABASE_URL = "https://your-project.supabase.co";
const SUPABASE_KEY = "your-anon-key";

Chrome:

1. Go to chrome://extensions
2. Enable Developer mode
3. Click Load unpacked → select the extension/ folder

Firefox:

1. Go to about:debugging → This Firefox
2. Click Load Temporary Add-on → select any file in extension/

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Tech Stack

Layer	Technology
CLI	Python 3
Entropy	os.urandom / crypto.getRandomValues
Hashing	SHA-256 (hashlib / crypto.subtle)
Database	Supabase (PostgreSQL)
Extension	JavaScript, HTML, CSS — MV3

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Security Notes

• Plaintext passwords are never stored — only their SHA-256 hashes
• All randomness comes from OS-level entropy
• The UNIQUE index on the hash column ensures O(1) duplicate detection