FileSend Companion
==================

The FileSend Companion is a secure file encryption and decryption tool designed for use with the FileSend.vip platform.

It allows you to locally encrypt files using a password before uploading them, and to decrypt `.lock` files received from others. No sensitive data ever leaves your device. Only you and the person you share the password with can access the original file.

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🔐 How It Works
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- Uses Argon2id to derive a strong encryption key from your password
- Uses AES-256-GCM for fast, authenticated encryption
- Stores all encryption metadata (salt, nonce, filename) inside the `.lock` file
- The only secret you need to share is the password

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📦 What's Included
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- `filesendcompanion.py` — the Python app
- This `README.txt`

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💡 How to Use
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1. Make sure you have Python 3.7 or later installed.

2. Install the required Python packages:
   > pip install cryptography argon2-cffi

3. Run the app:
   > python filesendcompanion.py

4. When prompted:
   - Select a file to encrypt or decrypt
   - Enter a password

5. What happens:
   - If you select a regular file: it is encrypted into a `.lock` file.
   - If you select a `.lock` file: it is decrypted back to the original file.

6. Share securely:
   - Upload the `.lock` file via https://filesend.vip/upload
   - Share the password through a separate, secure channel (e.g., Signal or phone)

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⚠️ Important Notes
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- The password is NEVER stored or sent.
- The `.lock` file contains the data needed to decrypt — **except the password**.
- If the password is lost or incorrect, the original file cannot be recovered.
- FileSend.vip staff cannot help recover lost passwords or decrypt files.

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🌐 More Info
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Website:     https://filesend.vip  
Tool Page:   https://filesend.vip/app  
Upload Files: https://filesend.vip/upload  
Retrieve Files: https://filesend.vip/download/<file-id>
