segatools/unityhook/hook.c
beerpsi 4041844ea9 mai2/mu3/cm: Integrate UnityDoorstop with segatools (#11)
[UnityDoorstop](https://github.com/NeighTools/UnityDoorstop) is a tool to execute managed code (.NET DLLs) before Unity does, useful for modding frameworks such as BepInEx.

This PR integrates parts of its code into segatools, so loading BepInEx is as simple as adding 2 lines to `segatools.ini`:
```ini
[unity]
targetAssembly=BepInEx\core\BepInEx.Preloader.dll
```

This PR also factors out the Unity path redirection hooks to its own module.

Reviewed-on: Dniel97/segatools#11
Co-authored-by: beerpsi <beerpsi@duck.com>
Co-committed-by: beerpsi <beerpsi@duck.com>
2024-04-15 19:30:28 +00:00

115 lines
2.9 KiB
C

#include <assert.h>
#include <stdbool.h>
#include "hook/table.h"
#include "hooklib/path.h"
#include "util/dprintf.h"
#include "doorstop.h"
#include "hook.h"
static bool unity_hook_initted;
static struct unity_config unity_config;
static const wchar_t *target_modules[] = {
L"mono.dll",
L"mono-2.0-bdwgc.dll",
L"cri_ware_unity.dll",
};
static const size_t target_modules_len = _countof(target_modules);
static void dll_hook_insert_hooks(HMODULE target);
static HMODULE WINAPI my_LoadLibraryW(const wchar_t *name);
static HMODULE (WINAPI *next_LoadLibraryW)(const wchar_t *name);
static const struct hook_symbol unity_kernel32_syms[] = {
{
.name = "LoadLibraryW",
.patch = my_LoadLibraryW,
.link = (void **) &next_LoadLibraryW,
},
};
void unity_hook_init(const struct unity_config *cfg, HINSTANCE self) {
assert(cfg != NULL);
if (!cfg->enable) {
return;
}
if (unity_hook_initted) {
return;
}
memcpy(&unity_config, cfg, sizeof(*cfg));
dll_hook_insert_hooks(NULL);
unity_hook_initted = true;
dprintf("Unity: Hook enabled.\n");
}
static void dll_hook_insert_hooks(HMODULE target) {
hook_table_apply(
target,
"kernel32.dll",
unity_kernel32_syms,
_countof(unity_kernel32_syms));
}
static HMODULE WINAPI my_LoadLibraryW(const wchar_t *name) {
const wchar_t *name_end;
const wchar_t *target_module;
bool already_loaded;
HMODULE result;
size_t name_len;
size_t target_module_len;
if (name == NULL) {
SetLastError(ERROR_INVALID_PARAMETER);
return NULL;
}
// Check if the module is already loaded
already_loaded = GetModuleHandleW(name) != NULL;
// Must call the next handler so the DLL reference count is incremented
result = next_LoadLibraryW(name);
if (!already_loaded && result != NULL) {
name_len = wcslen(name);
// mono entrypoint for injecting target_assembly
if (GetProcAddress(result, "mono_jit_init_version")) {
doorstop_mono_hook_init(&unity_config, result);
}
for (size_t i = 0; i < target_modules_len; i++) {
target_module = target_modules[i];
target_module_len = wcslen(target_module);
// Check if the newly loaded library is at least the length of
// the name of the target module
if (name_len < target_module_len) {
continue;
}
name_end = &name[name_len - target_module_len];
// Check if the name of the newly loaded library is one of the
// modules the path hooks should be injected into
if (_wcsicmp(name_end, target_module) != 0) {
continue;
}
dprintf("Unity: Loaded %S\n", target_module);
dll_hook_insert_hooks(result);
path_hook_insert_hooks(result);
}
}
return result;
}