BOOL AddDetour(DWORD address, PBYTE pfDetour, PBYTE pfTrampoline, DWORD Count, PCHAR Name)
{
CAutoLock Lock(&gDetourCS);
CHAR szName[MAX_STRING] = { 0 };
if (Name && Name[0] != '\0') {
strcpy_s(szName, Name);
} else {
strcpy_s(szName, "Unknown");
}
BOOL Ret = TRUE;
DebugSpew("AddDetour(%s, 0x%X,0x%X,0x%X,0x%X)", szName, address, pfDetour, pfTrampoline, Count);
if (FindDetour(address))
{
DebugSpew("Address for %s (0x%x) already detoured.", szName, address);
return FALSE;
}
OurDetours *detour = new OurDetours;
strcpy_s(detour->Name, szName);
detour->addr = address;
detour->count = Count;
memcpy(detour->array, (char *)address, Count);
detour->pNext = ourdetours;
if (ourdetours)
ourdetours->pLast = detour;
detour->pLast = 0;
if (pfTrampoline) {
// its an indirect jump, likely due to incremental linking. The actual
// function body is at the other end of the jump. We need to follow it.
if (pfTrampoline[0] == 0xe9) {
pfTrampoline = pfTrampoline + *(DWORD*)&pfTrampoline[1] + 5;
}
if (pfTrampoline[0] && pfTrampoline[1]) {
DWORD oldperm = 0, tmp;
VirtualProtectEx(GetCurrentProcess(), (LPVOID)pfTrampoline, 2, PAGE_EXECUTE_READWRITE, &oldperm);
pfTrampoline[0] = 0x90;
pfTrampoline[1] = 0x90;
VirtualProtectEx(GetCurrentProcess(), (LPVOID)pfTrampoline, 2, oldperm, &tmp);
}
}
if (pfDetour && !DetourFunctionWithEmptyTrampoline(pfTrampoline, (PBYTE)address, pfDetour))
{
detour->pfDetour = 0;
detour->pfTrampoline = 0;
Ret = FALSE;
DebugSpew("Detour of %s failed.", szName);
}
else
{
detour->pfDetour = pfDetour;
detour->pfTrampoline = pfTrampoline;
DebugSpew("Detour of %s was successful.", szName);
}
ourdetours = detour;
return Ret;
}
BOOL AddDetour(DWORD address, PBYTE pfDetour, PBYTE pfTrampoline, DWORD Count)
{
CAutoLock Lock(&gDetourCS);
BOOL Ret=TRUE;
DebugSpew("AddDetour(0x%X,0x%X,0x%X,0x%X)",address,pfDetour,pfTrampoline,Count);
if (FindDetour(address))
{
DebugSpew("Address 0x%x already detoured.",address);
return FALSE;
}
OurDetours *detour = new OurDetours;
detour->addr=address;
detour->count=Count;
memcpy(detour->array,(char *)address, Count);
detour->pNext=ourdetours;
if (ourdetours)
ourdetours->pLast=detour;
detour->pLast=0;
if (pfDetour && !DetourFunctionWithEmptyTrampoline(pfTrampoline,
(PBYTE)address,
pfDetour))
{
detour->pfDetour=0;
detour->pfTrampoline=0;
Ret=FALSE;
DebugSpew("Detour failed.");
}
else
{
detour->pfDetour=pfDetour;
detour->pfTrampoline=pfTrampoline;
DebugSpew("Detour success.");
}
ourdetours=detour;
return Ret;
}
