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improve hotpatching

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This commit is contained in:
FunkyFr3sh 2019-03-20 05:07:28 +01:00
parent 11c103f36c
commit 63584509e2
2 changed files with 26 additions and 3 deletions
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24
src/hook.c
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@ -86,8 +86,30 @@ PROC Hook_HotPatch(PROC function, PROC newFunction)
{
PROC result = function;
if (!function)
return result;
unsigned short *bytes = (unsigned short *)function;
if (function && *bytes == 0xFF8B) // mov edi, edi
if (*bytes == 0x25FF) // JMP DWORD PTR
{
char *address = (char *)function;
DWORD oldProtect;
if (VirtualProtect(address, 8, PAGE_EXECUTE_READWRITE, &oldProtect))
{
if (memcmp(address + 6, (const char[]) { 0xCC, 0xCC }, 2) == 0 ||
memcmp(address + 6, (const char[]) { 0x90, 0x90 }, 2) == 0)
{
memmove(address + 2, address, 6);
*((WORD *)(&address[0])) = 0xFF8B; // mov edi, edi
}
VirtualProtect(address, 8, oldProtect, &oldProtect);
}
}
if (*bytes == 0xFF8B) // mov edi, edi
{
char *address = ((char *)function) - 5;
DWORD oldProtect;