Secure OTP Sender (RyuuK32 USB Auth)

A Python script for sending OTPs (One-Time Passwords) via email, protected by USB-based authentication and an admin password.

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Features

• Multi-factor authentication: Requires both a USB drive with a secret file and an admin password.
• OTP delivery: Sends a randomly generated OTP to any email via Gmail SMTP.
• Credential security: Uses environment variables to store sensitive data safely.
• User-friendly: Clear CLI prompts and helpful error messages.
• Fun denial: Opens a YouTube short if authentication fails (because why not?).

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Requirements

• Python 3.7+
• Gmail account with App Passwords enabled
• A USB drive (default D:) with a file otp_auth_key.txt containing your secret code

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🛠️ Setup

1. Clone the Repository

git clone https://github.com/shkmannan/secure-login.git
cd secure-login

2. Install Dependencies

No external libraries are needed — uses only Python's standard library.

If you want to use .env files, install:

pip install python-dotenv

3. Set Environment Variables

Create a .env file (and never commit it):

GMAIL_USER=your_email@gmail.com
APP_PASSWORD=your_generated_app_password
ADMIN_PASSWORD=your_admin_password

Or set them directly in your shell environment.

4. Prepare USB Authentication

• Insert your USB drive (default D: — change in script if needed)
• On that drive, create a file named: otp_auth_key.txt
• Add your secret code (no spaces or newlines) to that file

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How to Enable Google SMTP (App Passwords)

1. Enable 2-Step Verification on your Google account: Google 2-Step Verification

2. Generate an App Password: App Passwords Setup

   • Choose “Mail” as the app
   • Choose “Other” for the device (name it however you want)
   • Copy the 16-character password and use it in your .env

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Usage

Run the script:

python otp_sender.py

Then follow the prompts for:

• USB authentication
• Admin password
• Recipient email

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Security Notes

• Never commit .env files or real credentials.
• Change the admin password from the default in the code.
• For more safety, consider encrypting otp_auth_key.txt.