lemonade-cryptography 1.1.0

Lightweight byte-oriented encryption library.

🍋 Lemonade Cryptography

Lemonade Cryptography is a lightweight byte-oriented encryption library based on modular arithmetic and symmetric key transformations.

Lemonade transforms binary data into encrypted data by applying mathematical operations between data bytes and cryptographic key bytes.

The core concept is:

Each byte of the data is encrypted by subtracting it from a corresponding byte of a secret key.

The original data can be recovered by applying the reverse operation using the same key.

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Installation

Install Lemonade Cryptography using pip:

pip install lemonade-cryptography

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Quick Start

from lemonade import encrypt, decrypt

message = b"Hello. We are looking for highly intelligent individuals."

crypt, key = encrypt(message)

print("Encrypted:")
print(crypt)

print("\nKey:")
print(key)

original = decrypt(crypt, key)

print("\nDecrypted:")
print(original)

Output:

Encrypted:
<encrypted bytes>

Key:
<secret key bytes>

Decrypted:
b'Hello. We are looking for highly intelligent individuals.'

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Features

• Symmetric key encryption
• Byte-oriented processing
• UTF-8 compatible through byte conversion
• Random cryptographic key generation
• Custom key encryption
• .lemon encrypted file format
• .sourkey key file format
• Lightweight Python API

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API Reference

encrypt()

encrypt(data_bytes: bytes) -> tuple[bytes, bytes]

Encrypts binary data and generates a random key with the same length as the input data.

Arguments

Argument	Type	Description
data_bytes	bytes	Data to encrypt

Returns

A tuple containing:

(
    encrypted_data,
    encryption_key
)

Example:

crypt, key = encrypt(b"Hello")

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encrypt_with_key()

encrypt_with_key(
    data_bytes: bytes,
    key_bytes: bytes
) -> bytes

Encrypts binary data using an existing key.

If the key is shorter than the data, the key bytes are repeated cyclically.

Example:

Data:
ABCDEFG

Key:
XYZ

Used key:
XYZXYZX

Arguments

Argument	Type	Description
data_bytes	bytes	Data to encrypt
key_bytes	bytes	Existing encryption key

Returns

Encrypted data:

bytes

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decrypt()

decrypt(
    crypt_bytes: bytes,
    key_bytes: bytes
) -> bytes

Decrypts Lemonade encrypted data using its key.

Arguments

Argument	Type	Description
crypt_bytes	bytes	Encrypted data
key_bytes	bytes	Encryption key

Returns

The original data:

bytes

Example:

message = decrypt(crypt, key)

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generate_key()

generate_key(length: int) -> bytes

Generates a cryptographically secure random key.

Arguments

Argument	Type	Description
length	int	Number of bytes

Returns

Generated key:

bytes

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File Processing

Lemonade supports its own encrypted file formats.

.lemon

Contains encrypted data.

Structure:

LEMON_MAGIC
encrypted bytes

.sourkey

Contains encryption keys.

Structure:

SOURKEY_MAGIC
key bytes

A .sourkey file can be reused to encrypt multiple data sources.

Example:

encrypt_with_sourkey_to_file(
    data,
    "output_directory",
    "key.sourkey"
)

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How It Works

Lemonade operates directly on byte values.

Example:

A = 65
B = 66
C = 67

The encryption operation is:

C = (M - K) mod 256

Where:

Symbol	Meaning
C	Encrypted byte
M	Original data byte
K	Key byte

The decryption operation reverses the transformation:

M = (C + K) mod 256

More technical details can be found in:

docs/algorithm.md

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Security Notice

Lemonade Cryptography is an experimental encryption library created for educational purposes and lightweight applications.

It is not intended to replace modern cryptographic standards such as AES or ChaCha20 in security-critical systems.

Always protect your encryption keys. Without the correct key, encrypted data cannot be recovered.

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License

Lemonade Cryptography is licensed under the MIT License.