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1. #Ida hide debugger how to#
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5. #Ida hide debugger windows#

If you have a point in the IDA disassembly and want to figure out what address it will be loaded in the DosBox Debugger, it's also not hard. If not, you may have found a false match, and should either search for the next occurrence, or specify extra bytes in your search until you find the correct match. If you do find a match, double check that the offset within the segment of the found match in IDA matches the offset of the instructions in the DosBox Debugger. Be careful to pick instructions that aren't far calls or jumps - such instructions are modified when a program loads depending where it loads in memory, so the IDA disassembly won't have the exact same bytes. If you break execution of the game at any point, you can simply use the Find Binary option in IDA to search for a sequence of bytes from the instructions shown in the DosBox Debugger disassembly area. This can be done either from the debugger to IDA, or from IDA to the debugger: One of the biggest initial steps when using the DosBox debugger is matching addresses in executable at run-time with your disassembly in IDA. See the DosBox Debugger Thread for more information.

#Ida hide debugger download#

The default distribution of DosBox doesn't have it enabled, but you can either compile DosBox with it enabled, or download a previously compiled executable.

#Ida hide debugger code#

Particularly if you initially write your code with names that closely match the names you give the methods in the disassembly.įor debugging purposes, if the game is a DOS game, the DosBox Debugger is the best tool I've found for executing and debugging DOS programs. When you start implementing code to implement game functionality, once you've got portions of the game disassembled, it can be immensely useful for tracking down bugs. I would recommend using a debugger particularly when reversing a game for the purpose of adding ScummVM support. Some prefer a more cerebral challenge of only figuring out code execution using a decompiler tool, whereas others may find using a debugger useful for figuring out what values are passed to functions. It's up to the individual if you want to use a debugger when reverse engineering a program. May prove useful as an alternative to the DosBox debugger.

#Ida hide debugger windows#

Works for newer binaries of games (32bit and Windows XP). Useful for watching how code executes, check when the internal functions are called, for dumping structures from memory of a target process and for changing data in memory on the fly. Nice tool for easy writing and injecting hooks to game binaries. Useful if you're familiar with C, and want to see what kinds of assembly are produced for various different code fragments.įRIDA - Dynamic Instrumentation Framework

#Ida hide debugger free#

This site has a free eBook that may be useful as a gentle introduction to reverse engineering techniques in general.Ī pretty cool online tool that lets you paste in C code and shows you the compiled assembly under various different compilers. "Reverse Engineering for Beginners" free book The Wikipedia is a good starting point, but you can also simply Google for an introduction as well. In 8086 assembly, apart from directly accessing ports, using interrupts is the primary means of accessing system functionality such as opening files, changing graphics modes, and many other things.įor those new to 8086 assembly language, you'll need a handy reference to learn the syntax. There are many different freeware hex editors available, so any other can be used just as easily.Ī nice reference for the operation of DOS interrupts. The DosBox Debugger is an invaluable tool for running old DOS games, to monitor how the program executes, and what values are generated by the executing code.Īlthough IDA has a built in hex viewer for the executable itself, the XVI32 tool is useful for viewing the contents of all the other files that come with a game. It is not as mature as IDA and is missing some features, but it has a nice decompiler. Ghidra Ghidra is an open source alternative to IDA that can be used for disassembling old games. The most recent freeware version no longer supports disassembling DOS games, but this earlier version still supports it. IDA Freeware Version 5.0 - IDA is the preferred tool for disassembling old games from scratch.

#Ida hide debugger how to#

This is only intended as an overview you'll still need to read other resources to learn 8086 assembly language, and learn how to use the various tools effectively.

It mainly focuses on resources and tools for reversing DOS game executables, but much of the strategies discussed may apply equally to other systems and debugging tools. This page is meant to provide some basic suggestions and strategies for people who are starting out with reverse engineering old adventure games, and aren't sure how to do it.