Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Update KismetDebuggerMod to use new global GNatives #745

Merged
merged 1 commit into from
Jan 7, 2025
Merged

Update KismetDebuggerMod to use new global GNatives #745

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 1 addition & 3 deletions cppmods/KismetDebuggerMod/include/KismetDebugger.hpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -10,9 +10,7 @@
namespace RC::GUI::KismetDebuggerMod
{
using namespace RC::Unreal;

typedef void (*FNativeFuncPtr)(UObject* Context, FFrame& Stack, void* RESULT_DECL);


auto expr_to_string(EExprToken expr) -> const char*;

struct PausedContext
Expand Down
59 changes: 7 additions & 52 deletions cppmods/KismetDebuggerMod/src/KismetDebugger.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -14,6 +14,7 @@
#include <Unreal/FString.hpp>
#include <Unreal/Core/Containers/Array.hpp>
#include <Unreal/FFrame.hpp>
#include <Unreal/Script.hpp>
#include <Unreal/ReflectedFunction.hpp>
#include <Unreal/Signatures.hpp>
#include <Unreal/Property/FObjectProperty.hpp>
Expand All @@ -34,7 +35,6 @@ namespace RC::GUI::KismetDebuggerMod
using namespace RC::Unreal;

FNativeFuncPtr GNativesOriginal[EExprToken::EX_Max];
FNativeFuncPtr* GNatives = nullptr;
volatile bool is_hooked = false; // cannot hook *immediately* as GNatives is populated at runtime

volatile bool should_pause = false;
Expand Down Expand Up @@ -80,8 +80,8 @@ namespace RC::GUI::KismetDebuggerMod
}

template <unsigned N> void hook_all() {
GNativesOriginal[N - 1] = GNatives[N - 1];
GNatives[N - 1] = &hook_expr<N - 1>;
GNativesOriginal[N - 1] = GNatives_Internal[N - 1];
GNatives_Internal[N - 1] = &hook_expr<N - 1>;
hook_all<N - 1>();
}
template <> void hook_all<0>() {}
Expand Down Expand Up @@ -231,7 +231,7 @@ namespace RC::GUI::KismetDebuggerMod
{
for (int i = 0; i < EExprToken::EX_Max; i++)
{
GNatives[i] = GNativesOriginal[i];
GNatives_Internal[i] = GNativesOriginal[i];
}
is_hooked = false;
should_pause = false;
Expand Down Expand Up @@ -273,64 +273,19 @@ namespace RC::GUI::KismetDebuggerMod
Output::send<LogLevel::Warning>(STR("[KismetDebugger]: Failed to load breakpoints: {}\n"), ensure_str(e.what()));
}

// scan for GNatives if it hasn't been found yet
if (GNatives == nullptr)
{
SignatureContainer gnatives = [&]() -> SignatureContainer {
return {
// UObject::SkipFunction
{ { "40 55 41 54 41 55 41 56 41 57 48 83 EC 30 48 8D 6C 24 20 48 89 5D 40 48 89 75 48 48 89 7D 50 48 8B 05 ?? ?? ?? ?? 48 33 C5 48 89 45 00 ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? 4D 8B ?? ?? 8B ?? 85 ?? 75 05 41 8B FC EB ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? 48 ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? 48 ?? E0" } },
[&](SignatureContainer& self) {
uint8_t* data = static_cast<uint8_t*>(self.get_match_address());
for (uint8_t* i : std::views::iota(data) | std::views::take(500))
{
// look for LEA instruction within the function body
if (i[0] == 0x4c && i[1] == 0x8d && ((i[2] & 0xc7) == 5) && i[2] > 0x20)
{
// LEA found, resolve relative jump
int32_t jmp;
memcpy(&jmp, i + 3, sizeof(jmp));

GNatives = reinterpret_cast<FNativeFuncPtr*>(i + 3 + 4 + jmp);

Output::send(STR("[KismetDebugger]: GNatives address: {}\n"), static_cast<void*>(GNatives));

self.get_did_succeed() = true;
return true;
}
}
Output::send(STR("[KismetDebugger]: GNatives: no LEA instruction found\n"));

return false;
},
[&](const SignatureContainer& self) {
if (!self.get_did_succeed())
{
Output::send<LogLevel::Warning>(STR("[KismetDebugger]: GNatives not found. Unable to hook.\n"));
}
}
};
}();

SinglePassScanner::SignatureContainerMap container_map;
std::vector<SignatureContainer> container;
container.emplace_back(gnatives);
container_map.emplace(ScanTarget::Core, container);
SinglePassScanner::start_scan(container_map);
}

if (GNatives != nullptr)
if (GNatives_Internal != nullptr)
{
// finally actually enable the debugger
hook_all<EExprToken::EX_Max>();
is_hooked = true;
return;
}
}
auto Debugger::disable() -> void
{
for (int i = 0; i < EExprToken::EX_Max; i++)
{
GNatives[i] = GNativesOriginal[i];
GNatives_Internal[i] = GNativesOriginal[i];
}
is_hooked = false;
should_pause = false;
Expand Down
Loading