mirror of
https://github.com/thomasxm/BOAZ_beta
synced 2026-06-06 16:54:29 +00:00
thomasxm
58 lines
1.9 KiB
Python
58 lines
1.9 KiB
Python
### Script to reduce file entropy.
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# def append_zeros_to_file(filename):
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# """Append 50 null bytes (0x00) to the end of a file."""
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# with open(filename, "ab") as file:
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# file.write(b'\x00' * 5000)
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# if __name__ == "__main__":
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# import sys
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# if len(sys.argv) < 2:
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# print("Usage: python append_zeros.py <filename>")
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# sys.exit(1)
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# filename = sys.argv[1]
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# append_zeros_to_file(filename)
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# print(f"Appended many zeros to {filename}")
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import math
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import sys
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def calculate_entropy(file_path):
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"""Calculate the Shannon entropy of a file."""
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with open(file_path, "rb") as file:
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byte_arr = file.read()
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file_size = len(byte_arr)
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if file_size == 0:
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# Empty file
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return 0
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# Calculate the frequency of each byte value in the file
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freq_list = [byte_arr.count(bytes([x])) / file_size for x in range(256)]
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# Calculate the entropy
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entropy = -sum([freq * math.log2(freq) for freq in freq_list if freq > 0])
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return entropy
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def append_zeros_to_file(file_path, num_zeros=200):
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"""Append specified number of 0x00 bytes to the end of a file."""
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with open(file_path, "ab") as file:
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file.write(b'\x00' * num_zeros)
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def reduce_entropy(file_path, threshold=6.1):
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"""Reduce the entropy of a file by appending 0x00 bytes until it's below the threshold."""
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entropy = calculate_entropy(file_path)
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print(f"Initial entropy: {entropy}")
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while entropy > threshold:
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append_zeros_to_file(file_path)
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entropy = calculate_entropy(file_path)
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print(f"Appended 200 zeros, new entropy: {entropy}")
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print(f"Final entropy: {entropy}")
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if __name__ == "__main__":
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if len(sys.argv) < 2:
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print("Usage: python entropy_reducer.py <filename>")
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sys.exit(1)
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file_path = sys.argv[1]
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reduce_entropy(file_path)
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