Function at 0x401000
Capabilities:
Check if file exists
Create process on windows
Create process suspended
Get file attributes
Query or enumerate registry value
Read .ini file
Resume thread
Set environment variable
Set registry value
Terminate process

Disassembly:
sub esp, 0xa3c
mov eax, dword [0x413004]
xor eax, esp
mov dword [esp + 0xa38], eax
push ebx
push ebp
push 0x104
lea eax, [esp + 0x384]
push 0
push eax
call fcn.00402450
push 0x104
lea eax, [esp + 0x188]
push 0
push eax
call fcn.00402450
push 0x104
lea eax, [esp + 0x90]
push 0
push eax
call fcn.00402450
push 0x104
lea eax, [esp + 0x52c]
push 0
push eax
call fcn.00402450
push 0x104
lea eax, [esp + 0x63c]
push 0
push eax
call fcn.00402450
push 0x12c
lea eax, [esp + 0x954]
push 0
push eax
call fcn.00402450
add esp, 0x48
lea eax, [esp + 0x484]
push 0x80
push 0
push eax
call fcn.00402450
push 0x40
lea eax, [esp + 0x44]
mov dword [esp + 0x40], 0x44
push 0
push eax
call fcn.00402450
add esp, 0x18
lea eax, [esp + 0x380]
push 0x104
push eax
push 0
call dword [sym.imp.KERNEL32.dll_GetModuleHandleA]
push eax
call dword [sym.imp.KERNEL32.dll_GetModuleFileNameA]
mov ebp, dword [sym.imp.KERNEL32.dll_lstrcpyA]
inc eax
test eax, eax
jle 0x401107
cmp byte [esp + eax + 0x380], 0x5c
je 0x4010f6
dec eax
test eax, eax
jg 0x4010e5
jmp 0x401107
lea ecx, [esp + 0x381]
push str.5DMCITY..........ini
add eax, ecx
push eax
call ebp
mov ebx, dword [sym.imp.KERNEL32.dll_GetFileAttributesA]
lea eax, [esp + 0x380]
push eax
call ebx
cmp eax, 0xffffffff
jne 0x401138
push 0x10
push 0x40d1b8
push str.Couldnt_find_the_configuration_file_5DMCITY..........ini_.
push 0
call dword [sym.imp.USER32.dll_MessageBoxA]
push 0
call dword [sym.imp.KERNEL32.dll_ExitProcess]
push esi
mov esi, dword [sym.imp.KERNEL32.dll_GetPrivateProfileStringA]
lea eax, [esp + 0x384]
push eax
push 0x104
lea eax, [esp + 0x184]
push eax
push 0x40d1b5
push str.SteamClient64Dll
push 0x40d21c
call esi
lea eax, [esp + 0x384]
push eax
push 0x104
lea eax, [esp + 0x80]
push eax
push 0x40d1b6
push 0x40d228
push 0x40d238
call esi
lea eax, [esp + 0x384]
push eax
push 0x104
lea eax, [esp + 0x510]
push eax
push 0
push 0x40d244
push 0x40d248
call esi
lea eax, [esp + 0x384]
push eax
push 0x104
lea eax, [esp + 0x614]
push eax
push 0
push str.ExeRunDir
push 0x40d260
call esi
lea eax, [esp + 0x384]
push eax
push 0x12c
lea eax, [esp + 0x920]
push eax
push 0
push str.ExeCommandLine
push 0x40d27c
call esi
lea eax, [esp + 0x384]
push eax
push 0x80
lea eax, [esp + 0x490]
push eax
push 0
push str.AppId
push str.SteamClient
call esi
cmp byte [esp + 0x488], 0
je 0x401245
mov esi, dword [sym.imp.KERNEL32.dll_SetEnvironmentVariableA]
lea eax, [esp + 0x488]
push eax
push str.SteamAppId
call esi
lea eax, [esp + 0x488]
push eax
push str.SteamGameId
call esi
push edi
push 0x104
lea eax, [esp + 0x288]
push 0
push eax
call fcn.00402450
mov edi, dword [sym.imp.KERNEL32.dll_lstrlenA]
lea eax, [esp + 0x18c]
add esp, 0xc
push eax
call edi
mov esi, dword [sym.imp.KERNEL32.dll_GetFullPathNameA]
test eax, eax
jle 0x40128f
nop word [eax + eax]
cmp byte [esp + eax + 0x180], 0x5c
je 0x4012e8
dec eax
test eax, eax
jg 0x401280
push 0x104
lea eax, [esp + 0x288]
push 0
push eax
call fcn.00402450
add esp, 0xc
lea eax, [esp + 0x180]
push eax
lea eax, [esp + 0x288]
push eax
call ebp
push 0x104
lea eax, [esp + 0x184]
push 0
push eax
call fcn.00402450
add esp, 0xc
lea eax, [esp + 0x180]
push 0
push eax
push 0x104
lea eax, [esp + 0x290]
push eax
call esi
lea eax, [esp + 0x7c]
push eax
call edi
test eax, eax
jle 0x4012ff
cmp byte [esp + eax + 0x7c], 0x5c
je 0x401352
dec eax
test eax, eax
jg 0x4012f3
push 0x104
lea eax, [esp + 0x288]
push 0
push eax
call fcn.00402450
add esp, 0xc
lea eax, [esp + 0x7c]
push eax
lea eax, [esp + 0x288]
push eax
call ebp
push 0x104
lea eax, [esp + 0x80]
push 0
push eax
call fcn.00402450
add esp, 0xc
lea eax, [esp + 0x7c]
push 0
push eax
push 0x104
lea eax, [esp + 0x290]
push eax
call esi
lea eax, [esp + 0x50c]
push eax
call edi
test eax, eax
jle 0x40136f
cmp byte [esp + eax + 0x50c], 0x5c
je 0x4013c8
dec eax
test eax, eax
jg 0x401360
push 0x104
lea eax, [esp + 0x288]
push 0
push eax
call fcn.00402450
add esp, 0xc
lea eax, [esp + 0x50c]
push eax
lea eax, [esp + 0x288]
push eax
call ebp
push 0x104
lea eax, [esp + 0x510]
push 0
push eax
call fcn.00402450
add esp, 0xc
lea eax, [esp + 0x50c]
push 0
push eax
push 0x104
lea eax, [esp + 0x290]
push eax
call esi
lea eax, [esp + 0x610]
push eax
call edi
test eax, eax
jle 0x4013e5
cmp byte [esp + eax + 0x610], 0x5c
je 0x40143e
dec eax
test eax, eax
jg 0x4013d6
push 0x104
lea eax, [esp + 0x288]
push 0
push eax
call fcn.00402450
add esp, 0xc
lea eax, [esp + 0x610]
push eax
lea eax, [esp + 0x288]
push eax
call ebp
push 0x104
lea eax, [esp + 0x614]
push 0
push eax
call fcn.00402450
add esp, 0xc
lea eax, [esp + 0x610]
push 0
push eax
push 0x104
lea eax, [esp + 0x290]
push eax
call esi
lea eax, [esp + 0x180]
push eax
call ebx
cmp eax, 0xffffffff
jne 0x401469
push 0x10
push 0x40d2b4
push str.Couldnt_find_the_requested_SteamClient64Dll.
push 0
call dword [sym.imp.USER32.dll_MessageBoxA]
push 0
call dword [sym.imp.KERNEL32.dll_ExitProcess]
lea eax, [esp + 0x7c]
push eax
call ebx
cmp eax, 0xffffffff
jne 0x401491
push 0x10
push 0x40d2f8
push str.Couldnt_find_the_requested_SteamClientDll.
push 0
call dword [sym.imp.USER32.dll_MessageBoxA]
push 0
call dword [sym.imp.KERNEL32.dll_ExitProcess]
lea eax, [esp + 0x50c]
push eax
call ebx
cmp eax, 0xffffffff
jne 0x4014bc
push 0x10
push 0x40d338
push str.Couldnt_find_the_requested_Exe_file.
push 0
call dword [sym.imp.USER32.dll_MessageBoxA]
push 0
call dword [sym.imp.KERNEL32.dll_ExitProcess]
cmp byte [esp + 0x50c], 0
je 0x40189d
lea eax, [esp + 0x20]
push eax
lea eax, [esp + 0x3c]
push eax
lea eax, [esp + 0x618]
push eax
push 0
push 4
push 1
push 0
push 0
lea eax, [esp + 0x93c]
push eax
lea eax, [esp + 0x530]
push eax
call dword [sym.imp.KERNEL32.dll_CreateProcessA]
test eax, eax
je 0x40189d
mov dword [esp + 0x18], 0x771f810d
call dword [sym.imp.KERNEL32.dll_GetCurrentProcessId]
mov dword [esp + 0x1c], eax
lea eax, [esp + 0x10]
push eax
push 0xf003f
push 0
push 0x40d3b0
push 0x80000001
call dword [sym.imp.ADVAPI32.dll_RegOpenKeyExA]
test eax, eax
je 0x401699
push 0
lea eax, [esp + 0x14]
push eax
push 0
push 0xf003f
push 0
push 0
push 0
push 0x40d3d4
push 0x80000001
call dword [sym.imp.ADVAPI32.dll_RegCreateKeyExA]
test eax, eax
je 0x40158a
push 0x10
push str.5DMCITY.........
push str.Unable_to_patch_Steam_process_informations_on_the_Windows_registry.
push 0
call dword [sym.imp.USER32.dll_MessageBoxA]
push 0
push dword [esp + 0x24]
call dword [sym.imp.KERNEL32.dll_TerminateProcess]
push 0
call dword [sym.imp.KERNEL32.dll_ExitProcess]
mov esi, dword [sym.imp.ADVAPI32.dll_RegSetValueExA]
lea eax, [esp + 0x18]
push 4
push eax
push 4
push 0
push 0x40d40c
push dword [esp + 0x24]
call esi
push 4
lea eax, [esp + 0x20]
push eax
push 4
push 0
push 0x40d45c
push dword [esp + 0x24]
call esi
lea eax, [esp + 0x7c]
push eax
call ebx
cmp eax, 0xffffffff
lea eax, [esp + 0x7c]
push eax
je 0x4015e4
call edi
inc eax
push eax
lea eax, [esp + 0x80]
push eax
push 1
push 0
push 0x40d460
jmp 0x4015f6
call edi
inc eax
push eax
push 0x40d1b7
push 1
push 0
push 0x40d470
push dword [esp + 0x24]
call esi
lea eax, [esp + 0x180]
push eax
call ebx
cmp eax, 0xffffffff
lea eax, [esp + 0x180]
push eax
je 0x40162a
call edi
inc eax
push eax
lea eax, [esp + 0x184]
push eax
push 1
push 0
push 0x40d480
jmp 0x40163c
call edi
inc eax
push eax
push 0x40d1c9
push 1
push 0
push 0x40d494
push dword [esp + 0x24]
call esi
push 0x40d4a8
call edi
inc eax
push eax
push 0x40d4b0
push 1
push 0
push 0x40d4b8
push dword [esp + 0x24]
call esi
push dword [esp + 0x10]
call dword [sym.imp.ADVAPI32.dll_RegCloseKey]
push dword [esp + 0x24]
call dword [sym.imp.KERNEL32.dll_ResumeThread]
push 0xffffffffffffffff
push dword [esp + 0x28]
call dword [sym.imp.KERNEL32.dll_WaitForSingleObject]
push dword [esp + 0x20]
mov esi, dword [sym.imp.KERNEL32.dll_CloseHandle]
call esi
push dword [esp + 0x24]
call esi
push 0
call dword [sym.imp.KERNEL32.dll_ExitProcess]
push 0x104
lea eax, [esp + 0x718]
mov dword [esp + 0x18], 1
push 0
push eax
call fcn.00402450
push 0x104
lea eax, [esp + 0x828]
push 0
push eax
call fcn.00402450
mov esi, dword [sym.imp.ADVAPI32.dll_RegQueryValueExA]
lea eax, [esp + 0x48]
add esp, 0x18
mov dword [esp + 0x30], 0x104
mov dword [esp + 0x34], 0x104
push eax
lea eax, [esp + 0x718]
push eax
lea eax, [esp + 0x1c]
push eax
push 0
push 0x40d4c4
push dword [esp + 0x24]
call esi
lea eax, [esp + 0x34]
push eax
lea eax, [esp + 0x81c]
push eax
lea eax, [esp + 0x1c]
push eax
push 0
push 0x40d4d4
push dword [esp + 0x24]
call esi
mov ebp, dword [sym.imp.ADVAPI32.dll_RegSetValueExA]
lea eax, [esp + 0x18]
push 4
push eax
push 4
push 0
push str.ActiveUser
push dword [esp + 0x24]
call ebp
push 4
lea eax, [esp + 0x20]
push eax
push 4
push 0
push 0x40d4f4
push dword [esp + 0x24]
call ebp
lea eax, [esp + 0x7c]
push eax
call ebx
cmp eax, 0xffffffff
lea eax, [esp + 0x7c]
push eax
je 0x40177a
call edi
inc eax
push eax
lea eax, [esp + 0x80]
push eax
push 1
push 0
push 0x40d4f8
jmp 0x40178c
call edi
inc eax
push eax
push 0x40d1ca
push 1
push 0
push 0x40d508
push dword [esp + 0x24]
call ebp
lea eax, [esp + 0x180]
push eax
call ebx
cmp eax, 0xffffffff
lea eax, [esp + 0x180]
push eax
je 0x4017c0
call edi
inc eax
push eax
lea eax, [esp + 0x184]
push eax
push 1
push 0
push 0x40d518
jmp 0x4017d2
call edi
inc eax
push eax
push 0x40d1cb
push 1
push 0
push 0x40d52c
push dword [esp + 0x24]
call ebp
push 0x40d540
call edi
inc eax
push eax
push str.Public
push 1
push 0
push str.Universe
push dword [esp + 0x24]
call ebp
push dword [esp + 0x10]
mov ebx, dword [sym.imp.ADVAPI32.dll_RegCloseKey]
call ebx
push dword [esp + 0x24]
call dword [sym.imp.KERNEL32.dll_ResumeThread]
push 0xffffffffffffffff
push dword [esp + 0x28]
call dword [sym.imp.KERNEL32.dll_WaitForSingleObject]
push dword [esp + 0x20]
mov esi, dword [sym.imp.KERNEL32.dll_CloseHandle]
call esi
push dword [esp + 0x24]
call esi
lea eax, [esp + 0x10]
push eax
push 0xf003f
push 0
push str.SoftwareValveSteamActiveProcess
push 0x80000001
call dword [sym.imp.ADVAPI32.dll_RegOpenKeyExA]
test eax, eax
jne 0x401895
lea eax, [esp + 0x714]
push eax
call edi
inc eax
push eax
lea eax, [esp + 0x718]
push eax
push 1
push 0
push str.SteamClientDll
push dword [esp + 0x24]
call ebp
lea eax, [esp + 0x818]
push eax
call edi
inc eax
push eax
lea eax, [esp + 0x81c]
push eax
push 1
push 0
push str.SteamClientDll64
push dword [esp + 0x24]
call ebp
push dword [esp + 0x10]
call ebx
push 0
call dword [sym.imp.KERNEL32.dll_ExitProcess]
push 0x10
push 0x40d374
push str.Unable_to_load_the_requested_EXE_file.
push 0
call dword [sym.imp.USER32.dll_MessageBoxA]
push 0
call dword [sym.imp.KERNEL32.dll_ExitProcess]