ByteOps/example.py at main · fxb-cocacoding/ByteOps · GitHub

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"""
Example use to decode a string in this

strcpy(vStackString, "nAA:P<;n@XRFa=cXO;>@sxt?avd\x1DJX");
    v28 = (char *)v62;
    do
    {
      vStackString[index] = 0x14 - ((index ^ (vStackString[index] + 0x67)) - 4);
      ++index;
    }
    while ( index != 31 );
"""

from byteops import ByteOps

def decode():
    vStackString = bytes([
        0x6E, 0x41, 0x41, 0x3A, 0x50, 0x3C, 0x3B, 0x6E, 0x40, 0x58, 0x52, 0x46, 0x61, 0x3D, 0x63, 0x58,
        0x4F, 0x3B, 0x3E, 0x40, 0x73, 0x78, 0x74, 0x3F, 0x61, 0x76, 0x64, 0x1D, 0x4A, 0x58, 0x00, 0x00
    ])
    result = bytearray(20)
    for index in range(31):
        temp = bytes([vStackString[index]])
        index_bytes = index.to_bytes(1, 'little')

        # (vStackString[index] + 0x67)
        add_result = ByteOps.add_byte(temp, bytes.fromhex("67"))

        # (index ^ (vStackString[index] + 0x67))
        xor_result = ByteOps.xor_byte(index_bytes, add_result)

        # ((index ^ (vStackString[index] + 0x67)) - 4)
        sub_result = ByteOps.sub_byte(xor_result, bytes.fromhex("04"))

        # 0x14 - ((index ^ (vStackString[index] + 0x67)) - 4)
        final_result = ByteOps.sub_byte(bytes.fromhex("14"), sub_result)

        # first and also only byte to the result store
        if index < 20:
            result[index] = final_result[0]

    print("".join(chr(i) for i in result))

decode()