NALEnc - Python Encryption Library

NALEnc is a lightweight Python encryption library designed for securely encrypting and decrypting text and binary data. With an intuitive interface and robust functionality, it is ideal for developers seeking a straightforward yet effective encryption solution.

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🚀 Features

• Flexible Input: Encrypt and decrypt strings, binary data, or NumPy arrays.
• Password Support: Accepts passwords as strings, bytes, lists of integers (0-255), or NumPy arrays.
• Optimized for Performance: Best suited for messages of size 2046n, where n ∈ N.
• Powered by NumPy: Leverages NumPy for efficient operations.

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📦 Installation

Install the library via pip:

pip install nalenc

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📝 Usage

🔗 Importing the Library

import nalenc
import numpy as np

🔑 Creating an Instance of NALEnc

To use the library, create an instance of the NALEnc class with a password. The password can be:

• A string
• A byte sequence
• An iterable of integers (each in the range 0-255)
• A NumPy array of integers (dtype must be np.uint8)

Example:

# Generate a password as a NumPy array
password = np.random.randint(0, 256, size=512, dtype=np.uint8)
nal = nalenc.NALEnc(password)

🔒 Encrypting Data

Use the encrypt method to encrypt a message. Supported input types:

• String
• Byte sequence
• Iterable of integers (0-255)
• NumPy array (dtype: np.uint8)

Example:

# Encrypt a string
encrypted = nal.encrypt("Hello, World!")

# Encrypt binary data
binary_data = b"\x89PNG\r\n\x1a\n"
encrypted_binary = nal.encrypt(binary_data)

# Encrypt a NumPy array
array_data = np.array([1, 2, 3, 4, 5], dtype=np.uint8)
encrypted_array = nal.encrypt(array_data)

🔓 Decrypting Data

Use the decrypt method to decrypt an encrypted message.

Example:

# Decrypt the encrypted string
decrypted = nal.decrypt(encrypted)  # Returns a list of integers

# Decrypt binary data
decrypted_binary = nal.decrypt(encrypted_binary)

# Decrypt a NumPy array
decrypted_array = nal.decrypt(encrypted_array)

📂 Working with Binary Files

NALEnc supports encrypting and decrypting binary files. Read the file as binary data, process it, and save the result. Cast the encrypted data to bytes before writing to a file.

Example:

# Encrypt a binary file
with open("input.bin", "rb") as f:
    data = f.read()

encrypted_data = nal.encrypt(data)

with open("output.enc", "wb") as f:
    f.write(bytes(encrypted_data))

# Decrypt the binary file
with open("output.enc", "rb") as f:
    encrypted_data = f.read()

decrypted_data = nal.decrypt(encrypted_data)

with open("decrypted.bin", "wb") as f:
    f.write(bytes(decrypted_data))

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📈 Optimal Message Size

For best performance, ensure message sizes are 2048n - 2, where n is a positive integer. This helps maximize efficiency during encryption and decryption.

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📚 API Reference

Class: NALEnc

Constructor

NALEnc(password: str | bytes | Iterable[int] | np.types.NDArray[np.uint8])

• password: The encryption password. Acceptable types:
  • String
  • Byte sequence
  • Iterable of integers (0-255)
  • NumPy array (np.types.NDArray[np.uint8])

Methods

encrypt(msg: str | bytes | Iterable[int] | np.types.NDArray[np.uint8])

Encrypts the given message.

• msg: The message to encrypt. Input types:
  • String
  • Byte sequence
  • Iterable of integers (0-255)
  • NumPy array (np.types.NDArray[np.uint8])
• Returns: The encrypted message as a list of integers.

decrypt(msg: str | bytes | Iterable[int] | np.types.NDArray[np.uint8])

Decrypts the given encrypted message.

• msg: The encrypted message. Input types:
  • String
  • Byte sequence
  • Iterable of integers (0-255)
  • NumPy array (np.types.NDArray[np.uint8])
• Returns: The decrypted message as a list of integers.

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💡 Example Code

import nalenc
import numpy as np

# Generate a random password
password = np.random.randint(0, 256, size=512, dtype=np.uint8)

# Create an instance of NALEnc
nal = nalenc.NALEnc(password)

# Encrypt a message
message = "Encrypt this message!"
encrypted = nal.encrypt(message)

# Decrypt the message
decrypted = nal.decrypt(encrypted)

print("Original:", message)
print("Encrypted:", bytes(encrypted))  # Cast to bytes for readability
print("Decrypted:", bytes(decrypted))

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📜 License

This library is licensed under the LGPL License. See the COPYING and COPYING.LESSER files for more information.

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For questions, feedback, or contributions, feel free to open an issue on the GitHub repository.