About steam VC

[ysc3839]

I bought steam vice city today. When I start the VCMP, the game shows "Application load error 5:0000065434". Then I noticed there is a "testapp.exe" in steam vice city directory. I renamed it to "gta-vc.exe" and start VCMP again, it works!

And I found that VCMPBrowser uses "vcmp-proxy.flt" to load "vcmp-steam.dll". I don't know why use this. Then I use my own launcher to start the game, VCMP says wrong gta version. However, I start the game process and wait 1 second before inject "vcmp-steam.dll", VCMP doesn't say wrong version and works very well. I hope developers should fix this to give players a better experience(steam version can't skip the intro movie, because .flt files load after the movie).

Finally, the browser can't autolocate steam version vice city, please also fix it!

[Stormeus]

And I found that VCMPBrowser uses "vcmp-proxy.flt" to load "vcmp-steam.dll". I don't know why use this. Then I use my own launcher to start the game, VCMP says wrong gta version. However, I start the game process and wait 1 second before inject "vcmp-steam.dll", VCMP doesn't say wrong version and works very well. I hope developers should fix this to give players a better experience(steam version can't skip the intro movie, because .flt files load after the movie).

This isn't a bug, this is because Steam games are DRM protected. You injected your DLL into an encrypted EXE and so when VC:MP did its version check routine it only read garbage. The reason it worked when you waited is because the EXE was decrypted by that point, hence why we use the steam-proxy — so that we can be completely sure that the VC:MP can be loaded.

[ysc3839]

And I found that VCMPBrowser uses "vcmp-proxy.flt" to load "vcmp-steam.dll". I don't know why use this. Then I use my own launcher to start the game, VCMP says wrong gta version. However, I start the game process and wait 1 second before inject "vcmp-steam.dll", VCMP doesn't say wrong version and works very well. I hope developers should fix this to give players a better experience(steam version can't skip the intro movie, because .flt files load after the movie).

This isn't a bug, this is because Steam games are DRM protected. You injected your DLL into an encrypted EXE and so when VC:MP did its version check routine it only read garbage. The reason it worked when you waited is because the EXE was decrypted by that point, hence why we use the steam-proxy — so that we can be completely sure that the VC:MP can be loaded.

Why not start a thread and wait it decrypt? I see many GTA 5 mods use this method.

Also, I think it shouldn't be called "DRM protected". It should be called "packed". And I think there is some method to hook the unpack function. I will have a try if I have time.

[ysc3839]

I found the OEP(Original Entry Point) of steam vice city. It's 0x00666BA0. But there is some trouble to hook it. However, this entry point calls 3 APIs to get information for WinMain. They are GetCommandLineA, GetStartupInfoA, GetModuleHandleA. I suggest you hook the GetStartupInfoA and load VCMP in it. Therefore, you can throw "vcmp-proxy" away!

@Stormeus

[ysc3839]

I found the OEP(Original Entry Point) of steam vice city. It's 0x00666BA0. But there is some trouble to hook it. However, this entry point calls 3 APIs to get information for WinMain. They are GetCommandLineA, GetStartupInfoA, GetModuleHandleA. I suggest you hook the GetStartupInfoA and load VCMP in it. Therefore, you can throw "vcmp-proxy" away!

@Stormeus
Sorry for disturb you. But I have waited for some days. Maybe you haven't seen it? Please give me a reply soon.

[Stormeus]

I'll test it when I get a chance.

[ysc3839]

I'll test it when I get a chance.

New! I found the code jump to OEP! The address is 0x00A4129E
 :edit: And this code is unencrypted, so you can hook it directly.
Assembly code around this address:

Code Select Expand

CPU Disasm
Address   Hex dump   Command
00A41298  |.  5D     pop ebp
00A41299  |.  5F     pop edi
00A4129A  |.  5E     pop esi
00A4129B  |.  5A     pop edx
00A4129C  |.  59     pop ecx
00A4129D  |.  5B     pop ebx
00A4129E  |.  FFE0   jmp eax
It's enough for you to make an inline hook!

[Stormeus]

Haven't gotten around to this yet since it'd require a browser update, which is more of a pain to modify since it doesn't self-update. This patch might very well work but it's somewhat irrelevant if the browser still refuses to directly inject the Steam DLL.

[ysc3839]

Haven't gotten around to this yet since it'd require a browser update, which is more of a pain to modify since it doesn't self-update. This patch might very well work but it's somewhat irrelevant if the browser still refuses to directly inject the Steam DLL.

I think you should add self-update to the browser.