AES Encryption Package

A Python package for AES (Advanced Encryption Standard) encryption and decryption, supporting AES-128, AES-192, and AES-256 bit encryption. This package is designed with a modular structure to make it easy to integrate into your projects and extend for custom requirements.

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Features

• Encryption and Decryption: Securely encrypt and decrypt data using AES with three different key lengths:
  • AES-128: 128-bit key size
  • AES-192: 192-bit key size
  • AES-256: 256-bit key size
• Key Expansion: Implements AES key schedule for efficient key derivation.
• Modular Design: Core components like State, Word, and Byte are reusable, simplifying extension or adaptation.
• High Performance: Optimized implementation for fast encryption and decryption.
• Cross-Platform: Works seamlessly across Windows, macOS, and Linux systems.

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Installation

Install the package using pip:

pip install aes_package

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Usage

This package provides functions to perform encryption and decryption easily. Below are some usage examples:

Encrypting a Message

from aes_module import aes_128_encrypt

# Define your message and key
message = "This is a secret message"
key = "mysecurekey12345"  # Must match the required key length

# Encrypt the message
encrypted_message = aes_128_encrypt(message, key)
print("Encrypted:", encrypted_message)

Decrypting a Message

from aes_module import aes_128_decrypt

# Decrypt the message
decrypted_message = aes_128_decrypt(encrypted_message, key)
print("Decrypted:", decrypted_message)

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Available Functions

The following functions are provided in the package:

Encryption

• aes_128_encrypt(message, key): Encrypt a message using AES-128.
• aes_192_encrypt(message, key): Encrypt a message using AES-192.
• aes_256_encrypt(message, key): Encrypt a message using AES-256.

Decryption

• aes_128_decrypt(message, key): Decrypt a message encrypted with AES-128.
• aes_192_decrypt(message, key): Decrypt a message encrypted with AES-192.
• aes_256_decrypt(message, key): Decrypt a message encrypted with AES-256.

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Testing

This package includes test cases to ensure reliability. You can run the tests using pytest:

1. Install pytest if not already installed:

   pip install pytest
   

2. Run the tests:

   pytest tests/
   

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Requirements

• Python Version: The package requires Python 3.6 or later.
• Dependencies: No external dependencies are required beyond the Python standard library.

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How AES Works

AES is a symmetric block cipher widely used in modern encryption. It works by processing data in fixed-size blocks (128 bits) and applying multiple rounds of substitutions, permutations, and mathematical transformations.

Key Lengths

• AES-128: Uses a 128-bit key (10 rounds of encryption).
• AES-192: Uses a 192-bit key (12 rounds of encryption).
• AES-256: Uses a 256-bit key (14 rounds of encryption).

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Contributing

We welcome contributions to improve the package! To contribute:

1. Fork the repository on GitHub.
2. Create a new branch for your feature or bug fix:

   git checkout -b feature-name
   

3. Commit your changes with descriptive messages.
4. Push the branch and submit a Pull Request.

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License

This project is licensed under the MIT License. See the LICENSE file for details.

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Acknowledgments

Special thanks to all contributors and the cryptography community for their continued development of secure encryption standards.