Fix some issues with 0x0-based MH_FILSETs and improve fallback arch/plat detection. This allows SKE filesets to load now, but more work should be done for improved support for these

Author: 0cyn

view/kernelcache/core/KernelCacheView.cpp

@@ -25,7 +25,8 @@ void KernelCacheViewType::Register()
 }
 
 Ref<BinaryView> KernelCacheViewType::Create(BinaryView* data)
-{uint32_t magic;
+{
+	uint32_t magic;
 	data->Read(&magic, data->GetStart(), 4);
 	if (magic != MH_CIGAM_64 && magic != MH_MAGIC_64) // FIXME 32 bit
 	{
@@ -133,7 +134,7 @@ Ref<Settings> KernelCacheViewType::GetLoadSettingsForData(BinaryView* data)
 		R"({
 		"title" : "Image Auto-Load Regex Pattern",
 		"type" : "string",
-		"default" : ".*libsystem_c.dylib",
+		"default" : "",
 		"description" : "A regex pattern to auto load matching images at the end of view init, defaults to the system_c image only."
 		})");
 
@@ -318,9 +319,16 @@ bool KernelCacheView::Init()
 		}
 		if (!foundBuildVersion)
 		{
-			LogError("Failed to find LC_BUILD_VERSION in subheader");
-			SetDefaultArchitecture(Architecture::GetByName("aarch64"));
-			SetDefaultPlatform(Platform::GetByName("macos-kernel-aarch64"));
+			// FIXME: Is it in-spec to have LC_BUILD_VERSION only in the super header?
+			// This is sufficient as a fallback but source should be referenced here.
+			LogWarn("Failed to find LC_BUILD_VERSION in subheader. Assuming macOS platform.");
+			std::map<std::string, Ref<Metadata>> metadataMap = {
+				{"machoplatform", new Metadata((uint64_t) MACHO_PLATFORM_MACOS)},
+			};
+			Ref<Metadata> metadata = new Metadata(metadataMap);
+			Ref<Platform> plat = g_kcViewType->RecognizePlatform(cpuType, GetDefaultEndianness(), this, metadata);
+			SetDefaultArchitecture(plat->GetArchitecture());
+			SetDefaultPlatform(plat);
 		}
 	}
 	else
@@ -329,13 +337,6 @@ bool KernelCacheView::Init()
 		return false;
 	}
 
-	if (textSegOffset == 0)
-	{
-		LogError("Failed to find __TEXT segment");
-		return false;
-	}
-
-
 	// Add Mach-O file header type info
 	EnumerationBuilder cpuTypeBuilder;
 	cpuTypeBuilder.AddMemberWithValue("CPU_TYPE_ANY", MACHO_CPU_TYPE_ANY);