fix: objc class superclass and isa bind lookups

blacktop · Apr 19, 2024 · 9391308 · 9391308
1 parent d2793fe
commit 9391308
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Showing 2 changed files with 64 additions and 0 deletions.
diff --git a/objc.go b/objc.go
@@ -464,6 +464,18 @@ func (f *File) GetObjCClass(vmaddr uint64) (*objc.Class, error) {
 				f.PutObjC(classPtr.SuperclassVMAddr, superClass)
 			}
 		}
+	} else {
+		bind, err := f.GetBindName(vmaddr + uint64(unsafe.Offsetof(classPtr.SuperclassVMAddr)))
+		if err != nil {
+			return nil, fmt.Errorf("failed to read super class objc_class_t at vmaddr: %#x; %v", vmaddr, err)
+		}
+		if info.Flags.IsRoot() {
+			superClass = &objc.Class{Name: bind}
+		} else if info.Flags.IsMeta() {
+			superClass = &objc.Class{Name: strings.TrimPrefix(bind, "_OBJC_METACLASS_$_")}
+		} else {
+			superClass = &objc.Class{Name: strings.TrimPrefix(bind, "_OBJC_CLASS_$_")}
+		}
 	}
 
 	isaClass := &objc.Class{}
@@ -494,6 +506,18 @@ func (f *File) GetObjCClass(vmaddr uint64) (*objc.Class, error) {
 				f.PutObjC(classPtr.IsaVMAddr, isaClass)
 			}
 		}
+	} else {
+		bind, err := f.GetBindName(vmaddr + uint64(unsafe.Offsetof(classPtr.IsaVMAddr)))
+		if err != nil {
+			return nil, fmt.Errorf("failed to read super class objc_class_t at vmaddr: %#x; %v", vmaddr, err)
+		}
+		if info.Flags.IsRoot() {
+			isaClass = &objc.Class{Name: bind}
+		} else if info.Flags.IsMeta() {
+			isaClass = &objc.Class{Name: strings.TrimPrefix(bind, "_OBJC_METACLASS_$_")}
+		} else {
+			isaClass = &objc.Class{Name: strings.TrimPrefix(bind, "_OBJC_CLASS_$_")}
+		}
 	}
 
 	return &objc.Class{
@@ -623,6 +647,18 @@ func (f *File) GetObjCClass2(vmaddr uint64) (*objc.Class, error) {
 				f.PutObjC(classPtr.SuperclassVMAddr, superClass)
 			}
 		}
+	} else {
+		bind, err := f.GetBindName(vmaddr + uint64(unsafe.Offsetof(classPtr.SuperclassVMAddr)))
+		if err != nil {
+			return nil, fmt.Errorf("failed to read super class objc_class_t at vmaddr: %#x; %v", vmaddr, err)
+		}
+		if info.Flags.IsRoot() {
+			superClass = &objc.Class{Name: bind}
+		} else if info.Flags.IsMeta() {
+			superClass = &objc.Class{Name: strings.TrimPrefix(bind, "_OBJC_METACLASS_$_")}
+		} else {
+			superClass = &objc.Class{Name: strings.TrimPrefix(bind, "_OBJC_CLASS_$_")}
+		}
 	}
 
 	isaClass := &objc.Class{}
@@ -653,6 +689,18 @@ func (f *File) GetObjCClass2(vmaddr uint64) (*objc.Class, error) {
 				f.PutObjC(classPtr.IsaVMAddr, isaClass)
 			}
 		}
+	} else {
+		bind, err := f.GetBindName(vmaddr + uint64(unsafe.Offsetof(classPtr.IsaVMAddr)))
+		if err != nil {
+			return nil, fmt.Errorf("failed to read super class objc_class_t at vmaddr: %#x; %v", vmaddr, err)
+		}
+		if info.Flags.IsRoot() {
+			isaClass = &objc.Class{Name: bind}
+		} else if info.Flags.IsMeta() {
+			isaClass = &objc.Class{Name: strings.TrimPrefix(bind, "_OBJC_METACLASS_$_")}
+		} else {
+			isaClass = &objc.Class{Name: strings.TrimPrefix(bind, "_OBJC_CLASS_$_")}
+		}
 	}
 
 	return &objc.Class{

diff --git a/types/objc/class.go b/types/objc/class.go
@@ -79,6 +79,22 @@ func (f ClassRoFlags) HasCxxStructors() bool {
 func (f ClassRoFlags) HasFuture() bool {
 	return (f & RO_FUTURE) != 0
 }
+func (f ClassRoFlags) String() string {
+	var out []string
+	if f.IsMeta() {
+		out = append(out, "META")
+	}
+	if f.IsRoot() {
+		out = append(out, "ROOT")
+	}
+	if f.HasCxxStructors() {
+		out = append(out, "HAS_CXX_STRUCTORS")
+	}
+	if f.HasFuture() {
+		out = append(out, "FUTURE")
+	}
+	return strings.Join(out, " | ")
+}
 
 type ClassRO struct {
 	Flags                ClassRoFlags