Link to unresolved symbol while injecting dll [duplicate] - c++

Question

This question already has answers here:
What is an undefined reference/unresolved external symbol error and how do I fix it?
(39 answers)
Closed 9 years ago.
I'm trying to inject a dll into a process, but after compiling I get
TestMain.obj : error LNK2019: link to unresolved external symbol __imp__StrStrIA#8 in function "unsigned long __cdecl GetPid(char *)" (?GetPid##YAKPAD#Z). After years of trying find my problem in my code and trying to google it , and meditating with Shaolin monks, I failed.
This is my code:
#include <windows.h>
#include <stdio.h>
#include <tlhelp32.h>
#include <shlwapi.h>
#include <iostream>
#include <conio.h>
using namespace std;
#define CREATE_THREAD_ACCESS (PROCESS_CREATE_THREAD | PROCESS_QUERY_INFORMATION | PROCESS_VM_OPERATION | PROCESS_VM_WRITE | PROCESS_VM_READ)
bool IsWindowsNT()
{
// check current version of Windows
DWORD version = GetVersion();
// parse return
DWORD majorVersion = (DWORD)(LOBYTE(LOWORD(version)));
DWORD minorVersion = (DWORD)(HIBYTE(LOWORD(version)));
return (version < 0x80000000);
}
BOOL InjectDLL(DWORD ProcessID,char* DLL_NAME)
{
HANDLE Proc;
char buf[50]={0};
LPVOID RemoteString, LoadLibAddy;
if(!ProcessID)
return false;
Proc = OpenProcess(PROCESS_ALL_ACCESS, FALSE, ProcessID);
LoadLibAddy = (LPVOID)GetProcAddress(GetModuleHandle("kernel32.dll"), "LoadLibraryA");
RemoteString = (LPVOID)VirtualAllocEx(Proc, NULL, strlen(DLL_NAME), MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
WriteProcessMemory(Proc, (LPVOID)RemoteString, DLL_NAME,strlen(DLL_NAME), NULL);
CreateRemoteThread(Proc, NULL, NULL, (LPTHREAD_START_ROUTINE)LoadLibAddy, (LPVOID)RemoteString, NULL, NULL);
CloseHandle(Proc);
return true;
}
DWORD GetPid(char *procName)
{
PROCESSENTRY32 pe;
HANDLE thSnapshot;
BOOL retval, ProcFound = false;
thSnapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
if(thSnapshot == INVALID_HANDLE_VALUE)
{
cout << "Error: unable to create toolhelp snapshot" << endl;
// MessageBox(NULL, "Error: unable to create toolhelp snapshot", "Loader", NULL);
return false;
}
pe.dwSize = sizeof(PROCESSENTRY32);
retval = Process32First(thSnapshot, &pe);
while(retval)
{
if(StrStrI(pe.szExeFile, procName) )
{
ProcFound = true;
break;
}
retval = Process32Next(thSnapshot,&pe);
pe.dwSize = sizeof(PROCESSENTRY32);
}
if (!ProcFound) return 0;
return pe.th32ProcessID;
}
BOOL LoadDll(char *procName, char *dllName)
{
DWORD ProcID = 0;
ProcID = GetPid(procName);
if(!(InjectDLL(ProcID, dllName)))
{
cout << "Process located, but injection failed" << endl;
_getch();
exit(1);
} // MessageBox(NULL, "Process located, but injection failed", "Loader", NULL);
else
{
cout << " Injection successfull!" << endl;
_getch();
}
return true;
}
int main()
{
char* ProcName = "notepad.exe";
char* DllName = "Main.dll";
LoadDll( ProcName, DllName );
return 0;
}
And my dll:
#include <Windows.h>
DWORD APIENTRY DllMain( HMODULE hModule, DWORD ul_reason_for_call, LPVOID lpReserved )
{
switch( ul_reason_for_call )
{
case DLL_PROCESS_ATTACH:
// hInstance = (HINSTANCE) hModule;
MessageBox( 0, "HOHOHOOHOHOHO!", "DLLHOOK", MB_OK );
return TRUE;
case DLL_PROCESS_DETACH:
break;
}
return TRUE;
}
So the main problem is that error.Thanks for answering.

Answer 1

Try adding
#pragma comment (lib, 'Shlwapi.lib')
below your other #includes