40 lines
1.5 KiB
Python
40 lines
1.5 KiB
Python
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# Get the IV key from OPT.bin (this is the second 16 bytes of the file)
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# decrypt the .opt using OPT.bin and get the first 16 bytes of the vhd. this is key1
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# key1 xor EB769045584641542020200000000000 (exfat file header) this will give you key2
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# key2 xor OPT IV key -> key3
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# replace OPT.bin's IV with key3 and decrypt
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import os
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import glob
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#function for taking bytes and xor'ing them
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def byte_xor(ba1, ba2):
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return bytes([_a ^ _b for _a, _b in zip(ba1, ba2)])
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print("You must decrypt the opt first using fstools and the OPT.bin\nPlace everything in the same directory\nONLY HAVE ONE VHD IN THE DIRECTORY AT A TIME")
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cwd = os.getcwd()
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#necessary because i couldn't figure out how else to do this, it's the exfat header duh
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with open(str(cwd) + "/exfat.bin", "rb") as f:
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exfat_HEADER = f.read(-1)
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print("exFAT Header = " + str(exfat_HEADER.hex()))
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#reads all bytees from OPT.bin then saves bytes (17, 32) and converts it to hexadecimal
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with open(str(cwd) + "/OPT.bin", "rb") as f:
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opt_IV = f.read(-1)
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opt_IV = opt_IV[16:]
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print("OPT IV = " + str(opt_IV.hex()))
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#puts all files with .vhd extension in a list, then pulls the first one in the list, will read first 16 bytes and convert to hexadecimal
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placeholder = glob.glob("*.vhd")
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vhd = str(placeholder[0])
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with open(str(cwd) + "/" + vhd, "rb") as f:
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key1 = f.read(16)
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print("key1 =" + str(key1.hex()))
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#calculates key 2 and key 3 then converts to hex
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key2 = byte_xor(key1, exfat_HEADER)
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print("key2 = " + str(key2.hex()))
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key3 = byte_xor(key2, opt_IV)
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print("key3 = " + str(key3.hex()))
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