Fix method offsets, map native code and silence class imports

Makefile

@@ -46,6 +46,9 @@ all: $(EXEC)
 
 r2 plugin: $(PLUGINS)
 
+test: $(EXEC) $(PLUGINS)
+	python3 test/test_import.py
+
 install-plugin: $(PLUGINS)
 	@[ -n "$(R2_USER_PLUGINS)" ] || (echo "r2 not found; cannot resolve R2_USER_PLUGINS"; exit 1)
 	mkdir -p "$(R2_USER_PLUGINS)"
@@ -96,4 +99,4 @@ clean:
 	rm -f $(EXEC) $(OBJS) $(LEGACY_OBJS) $(PLUGINS) $(CONFIG_H)
 
 
-.PHONY: all clean plugin install-plugin uninstall-plugin fmt bindist
+.PHONY: all clean plugin install-plugin uninstall-plugin fmt bindist test

README.md

@@ -94,6 +94,8 @@ After installing the plugins, open a Unity binary in r2 and use:
 ```text
 r2unity?       show help
 r2unity-D      detect and cache companion file paths
+r2unity-L      open/select and map the IL2CPP native library
+r2unity-c[*j]  list classes, or emit an import script / JSON
 r2unity-i[j]   show metadata summary
 r2unity-s      apply managed method flags/comments
 r2unity-s*     print the r2 commands instead of applying them
@@ -104,6 +106,11 @@ r2unity-S      emit managed-assembly SBOM text summary
 r2unity-Sj     emit managed-assembly CycloneDX JSON
 ```
 
+Use `.r2unity-c*` to import classes and method flags. The script loads the
+native companion library automatically, so `s sym.unity.<class>.<method>`
+followed by `pd` shows the method's native code. Methods without a native
+implementation retain address zero and do not get a seekable flag.
+
 Set `r2unity.metadata` and `r2unity.library` manually when auto-detection is not
 enough. The `bin_r2unity` plugin also lets radare2/rabin2 treat
 `global-metadata.dat` as a binary format, exposing sections, strings, symbols,

meson.build

@@ -91,7 +91,7 @@ if build_plugins
     warning('r2 was not found; installing plugins under ' + r2_plugindir)
   endif
 
-  shared_library(
+  core_plugin = shared_library(
     'core_r2unity',
     files('src/r2/core_r2unity.c') + lib_sources,
     include_directories: lib_inc,
@@ -115,4 +115,11 @@ if build_plugins
     install_dir: r2_plugindir,
   )
 
+  python = find_program('python3', required: false)
+  if python.found()
+    test('r2unity-class-import', python,
+      args: [files('test/test_import.py'), core_plugin],
+    )
+  endif
+
 endif

src/lib/bin/native.c

@@ -156,6 +156,7 @@ typedef struct {
 	R2UnityMetadata *meta;
 	Il2CppImageDefinition *images;
 	Il2CppTypeDefinition *types;
+	Il2CppMethodDefinition *methods;
 	size_t image_count;
 	size_t type_count;
 	size_t method_count;
@@ -166,13 +167,14 @@ static bool method_tables_init(R2UnityMethodTables *tables, R2UnityMetadata *met
 	tables->meta = meta;
 	tables->images = r2unity_get_images (meta, &tables->image_count);
 	tables->types = r2unity_get_type_definitions (meta, &tables->type_count);
-	tables->method_count = (size_t)r2unity_metadata_section_count (meta, R2U_SEC_METHODS);
-	return tables->images && tables->image_count && tables->types && tables->type_count && tables->method_count;
+	tables->methods = r2unity_get_method_definitions (meta, &tables->method_count);
+	return tables->images && tables->image_count && tables->types && tables->type_count && tables->methods && tables->method_count;
 }
 
 static void method_tables_fini(R2UnityMethodTables *tables) {
 	R_FREE (tables->images);
 	R_FREE (tables->types);
+	R_FREE (tables->methods);
 }
 
 static int image_index_by_name(R2UnityMethodTables *tables, const char *module_name) {
@@ -215,23 +217,27 @@ static size_t copy_image_method_table(R2UnityNativeView *view, R2UnityMethodTabl
 	if (image->typeStart < 0) {
 		return 0;
 	}
-	size_t local = 0;
 	size_t copied = 0;
 	size_t start = (size_t)image->typeStart;
 	size_t end = R_MIN (tables->type_count, start + image->typeCount);
-	for (size_t ti = start; ti < end && local < table_count; ti++) {
+	for (size_t ti = start; ti < end; ti++) {
 		const Il2CppTypeDefinition *td = &tables->types[ti];
 		if (td->methodStart < 0) {
-			local += td->method_count;
 			continue;
 		}
-		for (size_t k = 0; k < td->method_count && local < table_count; k++, local++) {
+		for (size_t k = 0; k < td->method_count; k++) {
 			size_t mi = (size_t)td->methodStart + k;
 			if (mi >= tables->method_count) {
 				continue;
 			}
+			ut32 token = tables->methods[mi].token;
+			ut32 rid = token & 0x00ffffff;
+			if ((token >> 24) != 0x06 || !rid || rid > table_count) {
+				continue;
+			}
 			ut64 raw = 0;
-			if (!read_ptr_at (view, table_va + (ut64)local * view->ptr_size, &raw)) {
+			// CodeGenModule method pointers are indexed by the MethodDef token RID.
+			if (!read_ptr_at (view, table_va + (ut64)(rid - 1) * view->ptr_size, &raw)) {
 				continue;
 			}
 			ut64 addr = code_va_from_raw (view, raw);

src/main.c

@@ -822,7 +822,7 @@ static void emit_class_r2(R2UnityMetadata *meta,
 		}
 		free (base);
 	}
-	printf ("ic+%s @ 0\n", r2klass);
+	printf ("'@0x0'ic+ %s\n", r2klass);
 
 	int mstart = td->methodStart;
 	for (int k = 0; methods && k < td->method_count && mstart >= 0 && (size_t)(mstart + k) < method_count; k++) {
@@ -833,7 +833,7 @@ static void emit_class_r2(R2UnityMetadata *meta,
 		}
 		char *mname = method_name_or_fallback (meta, &methods[mi], mi);
 		char *r2meth = r2_ic_name ("method", mname, mi);
-		printf ("ic+%s.%s @ 0x%" PFMT64x "\n", r2klass, r2meth, addr);
+		printf ("'@0x%" PFMT64x "'ic+ %s.%s\n", addr, r2klass, r2meth);
 		free (r2meth);
 		free (mname);
 	}

src/r2/core_r2unity.c

@@ -15,6 +15,7 @@ static const char *g_help_msg[] = {
 	"r2unity?", "", "show this help",
 	"r2unity-c", "[*j]", "enumerate classes, inheritance, methods, and fields",
 	"r2unity-D", "", "auto-detect companion files from current binary path",
+	"r2unity-L", "", "open/select and map the IL2CPP native library",
 	"r2unity-i", "[j]", "summary (metadata version, type/method counts)",
 	"r2unity-s", "[*j]", "apply/list managed/native symbols as flags + comments",
 	"r2unity-z", "[j]", "list managed string literals",
@@ -287,6 +288,28 @@ static const char *resolve_library_path(RCore *core) {
 	return R_STR_ISNOTEMPTY (v)? v: NULL;
 }
 
+static int cmd_load_library(RCore *core) {
+	const char *path = resolve_library_path (core);
+	if (!path) {
+		R_LOG_ERROR ("r2unity.library is not set. Run r2unity-D or set it manually");
+		return 1;
+	}
+	RBinFile *bf = r_bin_file_find_by_name (core->bin, path);
+	if (bf) {
+		if (!r_core_bin_set_by_fd (core, bf->fd) || !r_io_use_fd (core->io, bf->fd)) {
+			return 1;
+		}
+	} else if (!current_binary_matches_path (core, path)) {
+		RIODesc *desc = r_core_file_open (core, path, R_PERM_R, UT64_MAX);
+		if (!desc || !r_core_bin_load (core, path, UT64_MAX)) {
+			R_LOG_ERROR ("cannot load IL2CPP native library: %s", path);
+			return 1;
+		}
+	}
+	r_core_block_read (core);
+	return 0;
+}
+
 static R2UnityMetadata *open_metadata(RCore *core, RBuffer **out_buf) {
 	const char *path = resolve_metadata_path (core);
 	if (!path) {
@@ -667,10 +690,10 @@ static void emit_class_r2(RCore *core,
 	} else {
 		r_cons_printf (core->cons, "# class %s\n", name? name: r2klass);
 	}
-	r_cons_printf (core->cons, "ic+%s @ 0\n", r2klass);
+	r_cons_printf (core->cons, "'@0x0'ic+ %s\n", r2klass);
 	if (base) {
 		char *r2base = r2_ic_name ("type", base, 0, false);
-		r_cons_printf (core->cons, "ic+%s:%s @ 0\n", r2klass, r2base);
+		r_cons_printf (core->cons, "'@0x0'ic+ %s:%s\n", r2klass, r2base);
 		free (r2base);
 	}
 	free (base);
@@ -679,7 +702,7 @@ static void emit_class_r2(RCore *core,
 			char *iname = type_name_from_index (meta, types, type_count, interfaces[td->interfacesStart + k], false);
 			if (iname) {
 				char *r2iface = r2_ic_name ("type", iname, 0, false);
-				r_cons_printf (core->cons, "ic+%s:%s @ 0\n", r2klass, r2iface);
+				r_cons_printf (core->cons, "'@0x0'ic+ %s:%s\n", r2klass, r2iface);
 				free (r2iface);
 			}
 			free (iname);
@@ -693,7 +716,10 @@ static void emit_class_r2(RCore *core,
 		addr = addr > 0x1000? addr: 0;
 		char *mname = method_name_or_fallback (meta, &methods[mi], mi);
 		char *r2meth = r2_ic_name ("method", mname, mi, true);
-		r_cons_printf (core->cons, "ic+%s.%s @ 0x%" PFMT64x "\n", r2klass, r2meth, addr);
+		r_cons_printf (core->cons, "'@0x%" PFMT64x "'ic+ %s.%s\n", addr, r2klass, r2meth);
+		if (addr) {
+			r_cons_printf (core->cons, "'@0x%" PFMT64x "'f sym.unity.%s.%s 1\n", addr, r2klass, r2meth);
+		}
 		free (r2meth);
 		free (mname);
 	}
@@ -704,7 +730,7 @@ static void emit_class_r2(RCore *core,
 		char *fname = field_name_or_fallback (meta, &fields[fi], fi);
 		char *r2field = r2_ic_name ("field", fname, fi, false);
 		char *ftype = type_name_from_index (meta, types, type_count, fields[fi].typeIndex, true);
-		r_cons_printf (core->cons, "ic+%s..%s %s @ 0\n",
+		r_cons_printf (core->cons, "'@0x0'ic+ %s..%s %s\n",
 			r2klass,
 			r2field,
 			ftype? ftype: "unknown");
@@ -769,6 +795,9 @@ static int cmd_classes(RCore *core, char mode) {
 		r_cons_println (core->cons, "# r2 script generated by r2unity-c");
 		r_cons_printf (core->cons, "# Input file: %s\n", metadata_path && *metadata_path? metadata_path: "-");
 		print_native_result (core, &native_result);
+		if (has_ptrs) {
+			r_cons_println (core->cons, "r2unity-L");
+		}
 		if (!has_ptrs) {
 			r_cons_println (core->cons, "# Method addresses default to 0; run r2unity-D or set r2unity.library to recover native addresses.");
 		}
@@ -805,6 +834,9 @@ static int cmd_symbols(RCore *core, char mode) {
 		R_LOG_ERROR ("r2unity.library is not set. Run r2unity-D or set it manually");
 		return 1;
 	}
+	if (!mode && cmd_load_library (core)) {
+		return 1;
+	}
 	RBuffer *buf = NULL;
 	R2UnityMetadata *meta = open_metadata (core, &buf);
 	if (!meta) {
@@ -836,6 +868,9 @@ static int cmd_symbols(RCore *core, char mode) {
 		pj_ka (pj, "methods");
 	} else if (mode == '*') {
 		print_native_result (core, &native_result);
+		if (has_ptrs) {
+			r_cons_println (core->cons, "r2unity-L");
+		}
 	}
 
 	if (mode != 'j') {
@@ -1274,6 +1309,8 @@ static bool r2unity_call(RCorePluginSession *cps, const char *input) {
 		return cmd_classes (core, mode) == 0;
 	case 'D':
 		return cmd_detect (core, mode == 'j') == 0;
+	case 'L':
+		return cmd_load_library (core) == 0;
 	case 'i':
 		return cmd_info (core, mode == 'j') == 0;
 	case 's':