47 lines
1.2 KiB
Python
47 lines
1.2 KiB
Python
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from Crypto.Util.number import long_to_bytes, bytes_to_long
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from PIL import Image
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from hackingscripts import util
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def extract_bin(pixels):
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bin_stream = ""
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for p in pixels:
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r = util.lpad(bin(p[0])[2:], n, "0")
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g = util.lpad(bin(p[1])[2:], n, "0")
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b = util.lpad(bin(p[2])[2:], n, "0")
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bin_stream += r + g + b
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return bin_stream
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if __name__ == "__main__":
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key_img = Image.open("key.png")
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pix = key_img.load()
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width, height = key_img.size
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pixels_p = []
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pixels_q = []
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end_p = (54, 20)
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end_q = (54, 41)
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for y in range(height):
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for x in range(width):
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if y <= end_p[1]:
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pixels_p.append(pix[x,y])
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else:
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pixels_q.append(pix[x,y])
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p = int(extract_bin(pixels_p), 2)
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q = int(extract_bin(pixels_q), 2)
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e = 0x10001
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n = p * q
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phi_n = (p - 1) * (q - 1)
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d = power_mod(e, -1, phi_n)
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with open("flag.enc", "rb") as f:
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data = f.read()
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ct = bytes_to_long(data)
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pt = power_mod(ct, d, n)
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pt_b = long_to_bytes(pt)
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with open("decrypted.png", "wb") as g:
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g.write(pt_b)
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