Workflows early preview.

1 files changed, 156 insertions, 0 deletions

diff --git a/examples/workflows/objectivec/objectivec.cpp b/examples/workflows/objectivec/objectivec.cpp
new file mode 100644
index 00000000..e967c5e3
--- /dev/null
+++ b/examples/workflows/objectivec/objectivec.cpp
@@ -0,0 +1,156 @@
+#define _CRT_SECURE_NO_WARNINGS
+#define NOMINMAX
+
+#include <cinttypes>
+#include <cstdint>
+#include <cstdio>
+#include <string>
+#include <tuple>
+#include <unordered_map>
+
+#include "binaryninjaapi.h"
+#include "lowlevelilinstruction.h"
+#include "mediumlevelilinstruction.h"
+
+
+using namespace BinaryNinja;
+using namespace std;
+
+#if defined(_MSC_VER)
+#define snprintf _snprintf
+#endif
+
+
+extern "C"
+{
+	BN_DECLARE_CORE_ABI_VERSION
+
+	// TODO
+	// * __objc_const missing xrefs to implementations
+	void ObjectiveCAnalysis(Ref<AnalysisContext> analysisContext)
+	{
+		Ref<Function> function = analysisContext->GetFunction();
+		Ref<BinaryView> data = function->GetView();
+
+		static unordered_map<uint64_t, tuple<string, uint64_t>> classData;
+		static bool sInit = false;
+		if (!sInit) // TODO move to module-based workflow activity with run-once semantics
+		{
+			auto constSection = data->GetSectionByName("__objc_const");
+			if (!constSection)
+				return;
+
+			BinaryReader reader(data);
+			reader.SetEndianness(data->GetDefaultEndianness()); // TODO fix GetDefaultEndianness for non-elf formats
+			reader.Seek(constSection->GetStart());
+
+			reader.Read32();
+			reader.Read32();
+			reader.Read32();
+			reader.Read32();
+			reader.Read64();
+			uint64_t namePtr = reader.Read64();
+			reader.Read64();
+			reader.Read64();
+			reader.Read64();
+			reader.Read64();
+			reader.Read64();
+			uint32_t methodListFlags = reader.Read32();
+			uint32_t methodListCount = reader.Read32();
+			for (uint32_t i = 0; i < methodListCount; i++) // section end/symbol validation
+			{
+				uint64_t selector = reader.Read64();
+				uint64_t typePtr = reader.Read64();
+				uint64_t impPtr = reader.Read64();
+				//string methodName = reader.ReadCString(selector);
+				string typeEncoding = "";//reader.ReadCString(typePtr);
+				classData.insert_or_assign(selector, std::forward_as_tuple(typeEncoding, impPtr));
+			}
+
+			reader.Seek(namePtr);
+			string className = reader.ReadCString();
+
+			auto cfStringSection = data->GetSectionByName("__cfstring");
+			if (!cfStringSection)
+				return;
+
+			sInit = true;
+		}
+
+		bool updated = false;
+		uint8_t opcode[BN_MAX_INSTRUCTION_LENGTH];
+		InstructionInfo iInfo;
+
+		// // if (m_owner->IsAborted())
+		// // 	return;
+
+		// TODO fix this....
+		auto sym = data->GetSymbolByRawName("_objc_msgSend");
+		if (!sym)
+			return;
+		uint64_t msgSendAddr = sym->GetAddress();
+
+		Ref<LowLevelILFunction> llilFunc = analysisContext->GetLowLevelILFunction();
+		auto ssa = llilFunc->GetSSAForm();
+		if (!ssa)
+			return;
+		for (auto& i : ssa->GetBasicBlocks())
+		{
+			Ref<Architecture> arch = i->GetArchitecture();
+			for (size_t instrIndex = i->GetStart(); instrIndex < i->GetEnd(); instrIndex++)
+			{
+				LowLevelILInstruction instr = ssa->GetInstruction(instrIndex);
+
+				// TODO process subexpressions
+				if (instr.operation != LLIL_CALL_SSA)
+					continue;
+
+				LowLevelILInstruction destExpr = instr.GetDestExpr<LLIL_CALL_SSA>();
+				if (msgSendAddr == (uint64_t)destExpr.GetValue().value)
+				{
+					auto params = instr.GetParameterExprs<LLIL_CALL_SSA>();
+					if ((params.size() >= 2) && (params[0].operation == LLIL_REG_SSA) && (params[1].operation == LLIL_REG_SSA))
+					{
+						auto selfSSAReg = params[0].GetSourceSSARegister<LLIL_REG_SSA>();
+						auto selSSAReg = params[1].GetSourceSSARegister<LLIL_REG_SSA>();
+						if (auto itr = classData.find(ssa->GetSSARegisterValue(selSSAReg).value); itr != classData.end())
+						{
+							size_t llilIndex = ssa->GetNonSSAInstructionIndex(instrIndex);
+							LowLevelILInstruction llilInstr = llilFunc->GetInstruction(llilIndex);
+							auto destExpr = llilInstr.GetDestExpr<LLIL_CALL>();
+							const auto& [typeEncoding, impPtr] = itr->second;
+							destExpr.Replace(llilFunc->ConstPointer(destExpr.size, impPtr, destExpr));
+							llilInstr.Replace(llilFunc->Call(destExpr.exprIndex, llilInstr));
+							analysisContext->Inform("directRefs", "insert", impPtr, i->GetArchitecture(), instr.address);
+							updated = true;
+						}
+					}
+					// else
+					// 	LogError("Unhandled _objc_msgSend: 0x%" PRIx64, instr.address);
+				}
+			}
+		}
+
+		if (!updated)
+			return;
+
+		// Updates found, regenerate SSA form
+		llilFunc->GenerateSSAForm();
+	}
+
+
+	BINARYNINJAPLUGIN bool CorePluginInit()
+	{
+		Ref<Workflow> objectiveCWorkflow = Workflow::Instance()->Clone("ObjectiveCWorkflow");
+		objectiveCWorkflow->RegisterActivity(new Activity("extension.objectiveC", &ObjectiveCAnalysis));
+		objectiveCWorkflow->Insert("core.function.translateTailCalls", "extension.objectiveC");
+		Workflow::RegisterWorkflow(objectiveCWorkflow,
+			R"#({
+			"title" : "Objective C Meta-Analysis (Example)",
+			"description" : "This analysis stands in as an example to demonstrate Binary Ninja's extensible analysis APIs. ***Note** this feature is under active development and subject to change without notice.",
+			"capabilities" : []
+			})#");
+
+		return true;
+	}
+}