39 lines
1.3 KiB
Python
39 lines
1.3 KiB
Python
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from pathlib import Path
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def u16(data, off):
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return data[off] | (data[off + 1] << 8)
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def set_bytes(buf, off, blob):
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buf[off:off+len(blob)] = blob
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def set_u16(buf, off, value):
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buf[off] = value & 0xFF
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buf[off+1] = (value >> 8) & 0xFF
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data = bytearray(Path(r'd:\Ghidra\Crusader\REGRET.EXE').read_bytes())
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code_off = 0xD2840
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code = bytes.fromhex('55 8B EC 56 57 53 06 A1 2C 71 8B 16 2E 71 0B C2 74 4E C4 5E 06 83 EB 36 26 8B 47 02 D1 E0 D1 E0 C4 1E 30 44 01 C3 26 8B 37 26 8B 7F 02 8B C6 0B C7 74 2D C4 5E 06 26 FF B7 E3 00 26 FF B7 E1 00 26 FF B7 DC 00 26 FF B7 DA 00 26 FF B7 D8 00 26 FF B7 D6 00 57 56 52 50 9A FF FF 00 00 83 C4 14 FF 76 0C FF 76 0A FF 76 08 FF 76 06 9A FF FF 00 00 83 C4 08 07 5B 5F 5E 5D CB')
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set_bytes(data, code_off, code)
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patches = {
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0xD2C94: bytes.fromhex('03 00 FB 10 80 00 40 20'),
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0xD2E0C: bytes.fromhex('03 00 99 20 7D 00 F5 02'),
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0xD2E14: bytes.fromhex('03 00 AD 20 7F 00 8B 03'),
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}
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for off, blob in patches.items():
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set_bytes(data, off, blob)
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for rec_off in [0xD2C94,0xD2E0C,0xD2E14,0xD2E1C]:
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rec = data[rec_off:rec_off+8]
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src = u16(rec, 2)
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segidx = rec[4]
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target_off = u16(rec, 6)
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selector = 0x1000 + ((segidx - 1) << 3)
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op_off = 0xD0800 + src
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set_u16(data, op_off, target_off)
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set_u16(data, op_off+2, selector)
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print('2040-20dc=', data[0xD2840:0xD28DD].hex(' '))
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