Function at 0x423b90
Capabilities:
Check if file exists
Get file attributes
Get session user name
Link many functions at runtime
Query environment variable

Disassembly:
mov eax, 0x2804
call fcn.00431ce0
cmp dword [esi], 0
push ebx
push ebp
push edi
je 0x423ef1
push 0x1000
lea eax, [esp + 0x814]
push eax
push 0
call dword [sym.imp.KERNEL32.dll_GetModuleFileNameW]
mov ebp, dword [sym.imp.KERNEL32.dll_LoadLibraryW]
test eax, eax
jbe 0x423ca4
push str..local
lea ecx, [esp + 0x814]
push 0x1000
push ecx
call fcn.00432743
mov edi, dword [sym.imp.KERNEL32.dll_GetFileAttributesW]
add esp, 0xc
lea edx, [esp + 0x810]
push edx
call edi
cmp eax, 0xffffffff
jne 0x423ca4
mov ebx, dword [sym.imp.KERNEL32.dll_GetEnvironmentVariableW]
push 0x1000
lea eax, [esp + 0x814]
push eax
push str.ProgramFiles
call ebx
test eax, eax
jbe 0x423c50
push str.Debugging_Tools_for_Windowsdbghelp.dll
lea ecx, [esp + 0x814]
push 0x1000
push ecx
call fcn.00432743
add esp, 0xc
lea edx, [esp + 0x810]
push edx
call edi
cmp eax, 0xffffffff
je 0x423c50
lea eax, [esp + 0x810]
push eax
call ebp
mov dword [esi + 4], eax
cmp dword [esi + 4], 0
jne 0x423ca4
push 0x1000
lea ecx, [esp + 0x814]
push ecx
push str.ProgramFiles
call ebx
test eax, eax
jbe 0x423ca4
push str.Debugging_Tools_for_Windows_64_Bitdbghelp.dll
lea edx, [esp + 0x814]
push 0x1000
push edx
call fcn.00432743
add esp, 0xc
lea eax, [esp + 0x810]
push eax
call edi
cmp eax, 0xffffffff
je 0x423ca4
lea ecx, [esp + 0x810]
push ecx
call ebp
mov dword [esi + 4], eax
xor ebx, ebx
cmp dword [esi + 4], ebx
jne 0x423cb5
push str.dbghelp.dll
call ebp
mov dword [esi + 4], eax
mov eax, dword [esi + 4]
cmp eax, ebx
je 0x423ef1
mov edi, dword [sym.imp.KERNEL32.dll_GetProcAddress]
push str.SymInitialize
push eax
call edi
mov edx, dword [esi + 4]
push str.SymCleanup
push edx
mov dword [esi + 0x2c], eax
call edi
mov dword [esi + 0x10], eax
mov eax, dword [esi + 4]
push str.StackWalk64
push eax
call edi
mov ecx, dword [esi + 4]
push str.SymGetOptions
push ecx
mov dword [esi + 0x38], eax
call edi
mov edx, dword [esi + 4]
push str.SymSetOptions
push edx
mov dword [esi + 0x24], eax
call edi
mov dword [esi + 0x34], eax
mov eax, dword [esi + 4]
push str.SymFunctionTableAccess64
push eax
call edi
mov ecx, dword [esi + 4]
push str.SymGetLineFromAddr64
push ecx
mov dword [esi + 0x14], eax
call edi
mov edx, dword [esi + 4]
push str.SymGetModuleBase64
push edx
mov dword [esi + 0x18], eax
call edi
mov dword [esi + 0x1c], eax
mov eax, dword [esi + 4]
push str.SymGetModuleInfo64
push eax
call edi
mov ecx, dword [esi + 4]
push str.SymGetSymFromAddr64
push ecx
mov dword [esi + 0x20], eax
call edi
mov edx, dword [esi + 4]
push str.UnDecorateSymbolName
push edx
mov dword [esi + 0x28], eax
call edi
mov dword [esi + 0x3c], eax
mov eax, dword [esi + 4]
push str.SymLoadModule64
push eax
call edi
mov ecx, dword [esi + 4]
push str.SymGetSearchPath
push ecx
mov dword [esi + 0x30], eax
call edi
mov dword [esi + 0x40], eax
cmp dword [esi + 0x10], ebx
je 0x423ee1
cmp dword [esi + 0x14], ebx
je 0x423ee1
cmp dword [esi + 0x1c], ebx
je 0x423ee1
cmp dword [esi + 0x20], ebx
je 0x423ee1
cmp dword [esi + 0x24], ebx
je 0x423ee1
cmp dword [esi + 0x28], ebx
je 0x423ee1
cmp dword [esi + 0x2c], ebx
je 0x423ee1
cmp dword [esi + 0x34], ebx
je 0x423ee1
cmp dword [esi + 0x38], ebx
je 0x423ee1
cmp dword [esi + 0x3c], ebx
je 0x423ee1
cmp dword [esi + 0x30], ebx
je 0x423ee1
mov eax, dword [esp + 0x2814]
cmp eax, ebx
je 0x423df3
push eax
call fcn.00435977
add esp, 4
mov dword [esi + 0xc], eax
mov edx, dword [esi + 0xc]
mov eax, dword [esi + 8]
mov ecx, dword [esi + 0x2c]
push ebx
push edx
push eax
call ecx
mov ebx, dword [sym.imp.KERNEL32.dll_GetLastError]
test eax, eax
jne 0x423e22
mov edx, dword [esi]
mov edi, dword [edx]
push 0
push 0
call ebx
mov ecx, dword [esi]
push eax
mov eax, dword [edi + 0x10]
push str.SymInitialize
call eax
mov ecx, dword [esi + 0x24]
call ecx
mov edx, dword [esi + 0x34]
or eax, 0x210
push eax
call edx
push 0x3ff
mov ebp, eax
lea eax, [esp + 0x415]
push 0
push eax
mov byte [esp + 0x41c], 0
call fcn.004308d0
mov eax, dword [esi + 0x40]
add esp, 0xc
test eax, eax
je 0x423e88
mov edx, dword [esi + 8]
push 0x400
lea ecx, [esp + 0x414]
push ecx
push edx
call eax
test eax, eax
jne 0x423e88
mov eax, dword [esi]
mov edi, dword [eax]
push 0
push 0
call ebx
mov ecx, dword [esi]
mov edx, dword [edi + 0x10]
push eax
push str.SymGetSearchPath
call edx
push 0x3ff
lea eax, [esp + 0x15]
push 0
push eax
mov byte [esp + 0x1c], 0
call fcn.004308d0
add esp, 0xc
lea ecx, [esp + 0xc]
push ecx
lea edx, [esp + 0x14]
push edx
mov dword [esp + 0x14], 0x400
call dword [sym.imp.ADVAPI32.dll_GetUserNameA]
mov ecx, dword [esi]
mov eax, dword [ecx]
mov eax, dword [eax + 4]
lea edx, [esp + 0x10]
push edx
push ebp
lea edx, [esp + 0x418]
push edx
call eax
mov eax, 1
pop edi
pop ebp
pop ebx
add esp, 0x2804
ret 4
mov ecx, dword [esi + 4]
push ecx
call dword [sym.imp.KERNEL32.dll_FreeLibrary]
mov dword [esi + 4], ebx
mov dword [esi + 0x10], ebx
pop edi
pop ebp
xor eax, eax
pop ebx
add esp, 0x2804
ret 4