IDA database files for existing game ports

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sirlemonhead
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IDA database files for existing game ports

Post by sirlemonhead » Tue Mar 08, 2011 11:22 am

Hi guys,

I was wondering would it be possible to get hold of one or more IDA Pro database files for any of the ScummVM supported games that someone has done a good bit of work on?

I'm trying to RE an adventure game but am still quite unskilled at the process. Being able to get some tips from a well commented IDA database would be REALLY helpful.

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sev
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Post by sev » Tue Mar 08, 2011 12:31 pm

No, those are ScummVM team only. Feel free to e-mail me your questions, though or come to IRC, we will see how we can help.

And btw, what is the title of the game?


Eugene

sirlemonhead
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Post by sirlemonhead » Tue Mar 08, 2011 12:37 pm

The Sherlock Holmes: Case of the Serrated Scalpel game. I think someone from the team was working on this at some point, but i'm not aware how far he's got (a lot further than me I'd assume!)

I figured i'd start off with a game I like, that hasn't been done before, and see how it goes. I've got a decent part of the introduction cutscene figured out, which isn't bad for a weeks work (I'm having to learn assembly as I go which is slowing things!)

I'll drop into IRC later, but the questions I have are probably quite numerous and basic for anyone to entertain for too long :)

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md5
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Post by md5 » Tue Mar 08, 2011 1:46 pm

johndoe worked on this game a bit (search in the forums)

There's also this page, containing some resource viewer tools in Pascal:
http://oezmen.eu/gameresources/

androsynth7
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Re: IDA database files for existing game ports

Post by androsynth7 » Tue Mar 08, 2011 2:01 pm

sirlemonhead wrote: I'm trying to RE an adventure game but am still quite unskilled at the process. Being able to get some tips from a well commented IDA database would be REALLY helpful.
I've been thinking the same thing, but never mustered enough courage to ask the developers like you did. I have a good knowledge of x86 assembly language and some RE experience as well, but reverse engineering something as big and complex as a game from start to finish is something that I've never done (and I'm not even sure where to start). Seeing those database files would help, that's for sure.

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Post by sirlemonhead » Tue Mar 08, 2011 2:34 pm

I PMed johndoe a few days ago to see if he'd be willing to share what he's done so far with me, but I haven't heard back yet.

The handy thing about the sherlock holmes game is that it has a separate .exe for the introduction cutscene, which is quite small. I figured i'd start on that rather than the full blown game.exe itself.

androsynth7, were you looking to RE any game in particular? While I love monkey island/dott and the like, the Sherlock holmes game was the first adventure game I ever played, so i'd love to see it in ScummvM

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Strangerke
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Post by Strangerke » Tue Mar 08, 2011 2:53 pm

If I may add something... Don't rush on the intro: it uses another game engine (namely: tsage). It's easy to confirm: you'll find tsage.cfg and logo.exe uses it as well as RLB files.

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Post by sirlemonhead » Tue Mar 08, 2011 3:05 pm

I didn't know that..I see tsage.cfg now that you mention it.

logo.exe itself is a huge .exe file considering how little it does.

When you say don't rush on it..should I forget about it or make more of an effort to figure it out correctly?

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Post by md5 » Tue Mar 08, 2011 4:21 pm

tsage is a completely different engine, and it seems that it has been used just to play the intro of this game. I.e. the intro is done with the tsage engine, and the game with a different engine. dreammaster has been working with tsage (used in Ringworld), you can find his progress in his scummvm-misc project:
http://scummvm-misc.svn.sourceforge.net ... nes/tsage/

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Red_Breast
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Post by Red_Breast » Tue Mar 08, 2011 4:40 pm

Alien vs Predator is not an adventure game!

Just kidding - I couldn't resist a little tease sirlemonhead

For most / the rest of you don't even try understanding this.

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Post by sirlemonhead » Tue Mar 08, 2011 5:19 pm

Red_Breast wrote:Alien vs Predator is not an adventure game!

Just kidding - I couldn't resist a little tease sirlemonhead

For most / the rest of you don't even try understanding this.
I need a break from that stuff for a bit :)

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Post by sirlemonhead » Tue Mar 08, 2011 5:20 pm

md5 wrote:tsage is a completely different engine, and it seems that it has been used just to play the intro of this game. I.e. the intro is done with the tsage engine, and the game with a different engine. dreammaster has been working with tsage (used in Ringworld), you can find his progress in his scummvm-misc project:
http://scummvm-misc.svn.sourceforge.net ... nes/tsage/
Thanks for that. I've just been having a look at game.exe and I'm already seeing some common code from title.exe, so it wasn't all in vain :)

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john_doe
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Post by john_doe » Tue Mar 08, 2011 8:30 pm

Weird about that tsage thing, it really is tsage. I wonder how that came to be. I checked MobyGames but from the credits there it doesn't seem people from Mythos also were in Tsunami... Oh well...
And yes, game.exe and title.exe share a lot of code. title.exe is basically just a player for the vdx animations.

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Post by androsynth7 » Tue Mar 08, 2011 9:15 pm

sirlemonhead, I'm trying to RE Callahan's Crosstime Saloon by Legend Entertainment. The game's executable is a 32-bit program that uses DOS4GW dos extender, so all the addresses are linear and you don't have to track down the contents of segment registers, which is really neat. On the other hand, though, Watcom C compiler (which the game source code was compiled with) uses its own calling conventions and IDA Pro is having difficulties guessing function prototypes even for recognized library functions. Being realistic, I don't set any grand goals for myself, seeing learning and gaining experience as something I should focus on.

sirlemonhead
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Post by sirlemonhead » Tue Mar 08, 2011 10:00 pm

androsynth7 wrote:sirlemonhead, I'm trying to RE Callahan's Crosstime Saloon by Legend Entertainment. The game's executable is a 32-bit program that uses DOS4GW dos extender, so all the addresses are linear and you don't have to track down the contents of segment registers, which is really neat. On the other hand, though, Watcom C compiler (which the game source code was compiled with) uses its own calling conventions and IDA Pro is having difficulties guessing function prototypes even for recognized library functions. Being realistic, I don't set any grand goals for myself, seeing learning and gaining experience as something I should focus on.
Nice! that memory segmentation stuff in the 16bit code is causing me a few headaches. Pity about the function prototypes issue. Is there anything yo can do to help with that issue? I figured IDA would be pretty good with Watcom stuff.

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