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[原创]加壳脱壳知识点总结--类加载、方法执行流程以及脱壳实战
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发表于: 2024-6-11 18:12
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总结记录下ART环境下App启动流程中类加载流程以及相关知识，分析更深层次的脱壳点，加深对App加壳以及脱壳原理的理解。
环境：Android 8.0.0
这里直接从loadClass开始，DexClassloader,PathClassloader,InMemoryDexClassLoader这三个类的父类是BaseDexClassLoader，BaseDexClassLoader的父类是Classloader,在ClassLoader这个类里实现了loadClass。
protected Class<?> loadClass(String name, boolean resolve),这里官方的源码注释解释的比较清楚了，首先确定这个类是否被加载过,没有的话会开始走双亲委派的流程调用parent.loadClass,如果父加载器都没有加载过，则自己调用findClass开始查找class并加载
findClass在BaseDexClassLoader中重写了
DexPathList_public Class<?> findClass(String name, List<Throwable> suppressed) 这里的dexElements是在加载Dex时赋值的，保存的时当时加载的DexFile
Element_public Class<?> findClass(String name, ClassLoader definingContext,List<Throwable> suppressed),这个Element类是DexPathList的一个内部类
DexFile_loadClassBinaryName
DexFile_defineClass
DexFile_defineClassNative 这里进入了native层的DexFile中,这段代码在进行DexFile的注册。
__mirror::Class* ClassLinker::DefineClass__这里也是在初始化类，分配类空间等,有三个阶段SetupClass,LoadClass,LinkClass,关于类加载主要看LoadClass主要作用是将类的字段和方法信息从Dex文件中加载到内存中，并建立相应的数据结构。
ClassLinker::LoadClass
ClassLinker::LoadClassMembers 这里开始加载类的成员变量，方法，方法的加载有两步LoadMethod和LinkCode。
ClassLinker::LoadMethod LoadMethod为ArtMethod的基础属性赋值,并检查是否是构造函数,这里可以看到在设置CodeItemOffset，以前的函数抽取壳会在这个阶段回填字节码，通过hook LoadMethod即可脱到完整的Dex。
ClassLinker::LinkCode LinkCode的主要工作是把，以及一些相关操作例如分配空间，关联引用等，还有Native函数的绑定，最后会调用SetEntryPointFromQuickCompiledCode设置方法被调用时的入口，method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge())这段代码就是当oat被阻断后会把方法入口设置为解释执行入口。
类加载完成之后，一般就要调用类的方法了，所以继续看一下方法执行的流程，Android 8.0中主要是两种方法执行方式，解释执行和OAT的快速执行，解释执行主要是根据字节码执行方法，快速执行通过OAT中预先编译成的本地机器码来执行方法，对于加壳来说，阻断了OAT流程后系统会转向解释执行。
在安卓中，Java 函数可以通过两种主要的方式进行调用。一种是通过自然的代码执行路径进行调用，即在 Java 虚拟机中直接调用，另一种是通过 JNI进行调用，即通过本地代码与 Java 代码进行交互来实现函数调用，先说JNI调用的流程。
JNI调用Java函数主要是通过一系列的CallXXXMethod(+V代表无返回值+A代表参数以数组形式传递)JNI函数，这里找几个看一下实现方式，可以看到都调用了InvokeVirtualOrInterfaceWithVarArgs。
InvokeVirtualOrInterfaceWithVarArgs
InvokeWithArgArray
ArtMethod::invoke
这就到了比较关键的地方，通过反射和JNI调用都会走到这里,Invoke会判断方法调用的环境，方法类型，如果不是静态方法会进入art_quick_invoke_stub若目标方法已编译为快速路径，则经 INVOKE_STUB_CALL_AND_RETURN的汇编代码后，通过 PtrSizedFields 中的 entry_point_from_quick_compiled_code_ 跳转到目标方法的入口(entry_point_from_quick_compiled_code_ 也是自然通过代码执行Java代码的入口)。
这里有两种入口，一种是编译好的本地机器指令入口直接开始执行，另一种就是解释执行入口，在LinkCode函数说到当OAT被阻断后会调用method->SetEntryPointFromQuickCompiledCode(GetQuickToInterpreterBridge())，这样的话entry_point_from_quick_compiled_code_ 所指向的就是art_quick_to_interpreter_bridge这个桥函数了，这个桥函数也是汇编实现。
通过bl跳转到了artQuickToInterpreterBridge函数，之后的调用流程是artQuickToInterpreterBridge() → interpreter::EnterInterpreterFromEntryPoint() → interpreter::Execute()。
interpreter::Execute()
解释执行会通过kInterpreterImplKind的类型来判断执行哪种解释器，解释执行总的来说有三种方式goto型，汇编型和switch型，这三种的实现方式其实就和字面意思差不多，分别使用goto，汇编，switch来完成对字节码匹配执行，goto型在较早的版本还有，在本次分析的安卓8系统中已经不存在了，安卓8实现了汇编型和switch型，默认使用汇编型。
上面分析了类的加载流程和Java方法的调用流程，这里面大量出现了Dexfile，ArtMethod，两个地方都是可以用于脱壳，通过Dexfile可以直接dump Dexfile，而通过ArtMethod也可以间接获取到Dexfile对象，这里随便找一个，loadClassMember方法进行实战，还是用的frida hook的方式。
这里代码用上次的改一下即可
其实总结的知识点已经涉及到抽取壳脱壳了，抽取壳的脱壳后面再写。
https://blog.csdn.net/u013989732/article/details/80670989
https://blog.csdn.net/hl09083253cy/article/details/78418651
https://blog.csdn.net/hl09083253cy/article/details/78418702
https://rk700.github.io/2017/06/30/hook-on-android-n/
https://blog.csdn.net/u013989732/article/details/80717762/
public Class<?> loadClass(String name) throws ClassNotFoundException { return loadClass(name, false);
}
public Class<?> loadClass(String name) throws ClassNotFoundException { return loadClass(name, false);
}
protected Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException
{ // First, check if the class has already been loaded
Class<?> c = findLoadedClass(name);
if (c == null) {
try {
if (parent != null) {
c = parent.loadClass(name, false);
} else {
c = findBootstrapClassOrNull(name);
}
} catch (ClassNotFoundException e) {
// ClassNotFoundException thrown if class not found
// from the non-null parent class loader
}
if (c == null) {
// If still not found, then invoke findClass in order
// to find the class.
c = findClass(name);
}
}
return c;
}
protected Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException
{ // First, check if the class has already been loaded
Class<?> c = findLoadedClass(name);
if (c == null) {
try {
if (parent != null) {
c = parent.loadClass(name, false);
} else {
c = findBootstrapClassOrNull(name);
}
} catch (ClassNotFoundException e) {
// ClassNotFoundException thrown if class not found
// from the non-null parent class loader
}
if (c == null) {
// If still not found, then invoke findClass in order
// to find the class.
c = findClass(name);
}
}
return c;
}
@Override protected Class<?> findClass(String name) throws ClassNotFoundException {
List<Throwable> suppressedExceptions = new ArrayList<Throwable>();
Class c = pathList.findClass(name, suppressedExceptions);
if (c == null) {
ClassNotFoundException cnfe = new ClassNotFoundException(
"Didn't find class \"" + name + "\" on path: " + pathList);
for (Throwable t : suppressedExceptions) {
cnfe.addSuppressed(t);
}
throw cnfe;
}
return c;
}
@Override protected Class<?> findClass(String name) throws ClassNotFoundException {
List<Throwable> suppressedExceptions = new ArrayList<Throwable>();
Class c = pathList.findClass(name, suppressedExceptions);
if (c == null) {
ClassNotFoundException cnfe = new ClassNotFoundException(
"Didn't find class \"" + name + "\" on path: " + pathList);
for (Throwable t : suppressedExceptions) {
cnfe.addSuppressed(t);
}
throw cnfe;
}
return c;
}
public Class<?> findClass(String name, List<Throwable> suppressed) {
for (Element element : dexElements) {
Class<?> clazz = element.findClass(name, definingContext, suppressed);
if (clazz != null) {
return clazz;
}
}
if (dexElementsSuppressedExceptions != null) {
suppressed.addAll(Arrays.asList(dexElementsSuppressedExceptions));
}
return null;
}
public Class<?> findClass(String name, List<Throwable> suppressed) {
for (Element element : dexElements) {
Class<?> clazz = element.findClass(name, definingContext, suppressed);
if (clazz != null) {
return clazz;
}
}
if (dexElementsSuppressedExceptions != null) {
suppressed.addAll(Arrays.asList(dexElementsSuppressedExceptions));
}
return null;
}
public Class<?> findClass(String name, ClassLoader definingContext, List<Throwable> suppressed) {
return dexFile != null ? dexFile.loadClassBinaryName(name, definingContext, suppressed)
: null;
}
public Class<?> findClass(String name, ClassLoader definingContext, List<Throwable> suppressed) {
return dexFile != null ? dexFile.loadClassBinaryName(name, definingContext, suppressed)
: null;
}
public Class loadClassBinaryName(String name, ClassLoader loader, List<Throwable> suppressed) {
return defineClass(name, loader, mCookie, this, suppressed);
}
public Class loadClassBinaryName(String name, ClassLoader loader, List<Throwable> suppressed) {
return defineClass(name, loader, mCookie, this, suppressed);
}
private static Class defineClass(String name, ClassLoader loader, Object cookie,
DexFile dexFile, List<Throwable> suppressed) {
Class result = null;
try {
result = defineClassNative(name, loader, cookie, dexFile);
} catch (NoClassDefFoundError e) {
if (suppressed != null) {
suppressed.add(e);
}
} catch (ClassNotFoundException e) {
if (suppressed != null) {
suppressed.add(e);
}
}
return result;
}private static Class defineClass(String name, ClassLoader loader, Object cookie,
DexFile dexFile, List<Throwable> suppressed) {
Class result = null;
try {
result = defineClassNative(name, loader, cookie, dexFile);
} catch (NoClassDefFoundError e) {
if (suppressed != null) {
suppressed.add(e);
}
} catch (ClassNotFoundException e) {
if (suppressed != null) {
suppressed.add(e);
}
}
return result;
}static jclass DexFile_defineClassNative(JNIEnv* env,jclass,jstring javaName,jobject javaLoader, jobject cookie,jobject dexFile) {
... for (auto& dex_file : dex_files) {
const DexFile::ClassDef* dex_class_def =
OatDexFile::FindClassDef(*dex_file, descriptor.c_str(), hash);
if (dex_class_def != nullptr) {
ScopedObjectAccess soa(env);
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
StackHandleScope<1> hs(soa.Self());
Handle<mirror::ClassLoader> class_loader(
hs.NewHandle(soa.Decode<mirror::ClassLoader>(javaLoader)));
ObjPtr<mirror::DexCache> dex_cache =
class_linker->RegisterDexFile(*dex_file, class_loader.Get());
if (dex_cache == nullptr) {
// OOME or InternalError (dexFile already registered with a different class loader).
soa.Self()->AssertPendingException();
return nullptr;
}
ObjPtr<mirror::Class> result = class_linker->DefineClass(soa.Self(),descriptor.c_str(),hash,class_loader,*dex_file,*dex_class_def);
// Add the used dex file. This only required for the DexFile.loadClass API since normal
// class loaders already keep their dex files live.
class_linker->InsertDexFileInToClassLoader(soa.Decode<mirror::Object>(dexFile),class_loader.Get());
if (result != nullptr) {
VLOG(class_linker) << "DexFile_defineClassNative returning " << result
<< " for " << class_name.c_str();
return soa.AddLocalReference<jclass>(result);
}
}
}
VLOG(class_linker) << "Failed to find dex_class_def " << class_name.c_str();
return nullptr;
}static jclass DexFile_defineClassNative(JNIEnv* env,jclass,jstring javaName,jobject javaLoader, jobject cookie,jobject dexFile) {
... for (auto& dex_file : dex_files) {
const DexFile::ClassDef* dex_class_def =
OatDexFile::FindClassDef(*dex_file, descriptor.c_str(), hash);
if (dex_class_def != nullptr) {
ScopedObjectAccess soa(env);
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
StackHandleScope<1> hs(soa.Self());
Handle<mirror::ClassLoader> class_loader(
hs.NewHandle(soa.Decode<mirror::ClassLoader>(javaLoader)));
ObjPtr<mirror::DexCache> dex_cache =
class_linker->RegisterDexFile(*dex_file, class_loader.Get());
if (dex_cache == nullptr) {
// OOME or InternalError (dexFile already registered with a different class loader).
soa.Self()->AssertPendingException();
return nullptr;
}
ObjPtr<mirror::Class> result = class_linker->DefineClass(soa.Self(),descriptor.c_str(),hash,class_loader,*dex_file,*dex_class_def);
// Add the used dex file. This only required for the DexFile.loadClass API since normal
// class loaders already keep their dex files live.
class_linker->InsertDexFileInToClassLoader(soa.Decode<mirror::Object>(dexFile),class_loader.Get());
if (result != nullptr) {
VLOG(class_linker) << "DexFile_defineClassNative returning " << result
<< " for " << class_name.c_str();
return soa.AddLocalReference<jclass>(result);
}
}
}
VLOG(class_linker) << "Failed to find dex_class_def " << class_name.c_str();
return nullptr;
}mirror::Class* ClassLinker::DefineClass(Thread* self,const char* escriptor,size_t hash,Handle<mirrr::ClassLoader> class_loader,const DexFile& dex_file,const DexFile::ClassDef dex_class_def) {
...klass->SetDexCache(dex_cache);
SetupClass(*new_dex_file, *new_class_def, klass, class_loader.Get());
... // Load the fields and other things after we arenserted in the table. This is so that we don't
// end up allocating unfree-able linear alloc rources and then lose the race condition. The
// other reason is that the field roots are onlvisited from the class table. So we need to be
// inserted before we allocate / fill in these field
LoadClass(self, *new_dex_file, *new_class_def, klass);
...if (!LinkClass(self, descriptor, klass, interfaces, &h_new_class)) {
// Linking failed.
if (!klass->IsErroneous()) {
mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self);
}
return nullptr;
}
...mirror::Class* ClassLinker::DefineClass(Thread* self,const char* escriptor,size_t hash,Handle<mirrr::ClassLoader> class_loader,const DexFile& dex_file,const DexFile::ClassDef dex_class_def) {
...klass->SetDexCache(dex_cache);
SetupClass(*new_dex_file, *new_class_def, klass, class_loader.Get());
... // Load the fields and other things after we arenserted in the table. This is so that we don't
// end up allocating unfree-able linear alloc rources and then lose the race condition. The
// other reason is that the field roots are onlvisited from the class table. So we need to be
// inserted before we allocate / fill in these field
LoadClass(self, *new_dex_file, *new_class_def, klass);
...if (!LinkClass(self, descriptor, klass, interfaces, &h_new_class)) {
// Linking failed.
if (!klass->IsErroneous()) {
mirror::Class::SetStatus(klass, mirror::Class::kStatusErrorUnresolved, self);
}
return nullptr;
}
...void ClassLinker::LoadClass(Thread* self,
const DexFile& dex_file,
const DexFile::ClassDef& dex_class_def,
Handle<mirror::Class> klass) {
const uint8_t* class_data = dex_file.GetClassData(dex_class_def);
if (class_data == nullptr) {
return; // no fields or methods - for example a marker interface
}
LoadClassMembers(self, dex_file, class_data, klass);
}void ClassLinker::LoadClass(Thread* self,
const DexFile& dex_file,
const DexFile::ClassDef& dex_class_def,
Handle<mirror::Class> klass) {
const uint8_t* class_data = dex_file.GetClassData(dex_class_def);
if (class_data == nullptr) {
return; // no fields or methods - for example a marker interface
}
LoadClassMembers(self, dex_file, class_data, klass);
}void ClassLinker::LoadClassMembers(Thread* self,const DexFile& dex_file,const uint8_t* class_data,Handle<mirror::Class> klass) {
{ // Note: We cannot have thread suspension until the field and method arrays are setup or else
// Class::VisitFieldRoots may miss some fields or methods.
ScopedAssertNoThreadSuspension nts(__FUNCTION__);
// Load static fields.
... for (; it.HasNextStaticField(); it.Next()) {
uint32_t field_idx = it.GetMemberIndex();
DCHECK_GE(field_idx, last_field_idx); // Ordering enforced by DexFileVerifier.
if (num_sfields == 0 || LIKELY(field_idx > last_field_idx)) {
DCHECK_LT(num_sfields, it.NumStaticFields());
LoadField(it, klass, &sfields->At(num_sfields));
++num_sfields;
last_field_idx = field_idx;
}
}
// Load instance fields.
LengthPrefixedArray<ArtField>* ifields = AllocArtFieldArray(self,allocator,it.NumInstanceFields());
size_t num_ifields = 0u;
last_field_idx = 0u;
for (; it.HasNextInstanceField(); it.Next()) {
uint32_t field_idx = it.GetMemberIndex();
DCHECK_GE(field_idx, last_field_idx); // Ordering enforced by DexFileVerifier.
if (num_ifields == 0 || LIKELY(field_idx > last_field_idx)) {
DCHECK_LT(num_ifields, it.NumInstanceFields());
LoadField(it, klass, &ifields->At(num_ifields));
++num_ifields;
last_field_idx = field_idx;
}
}
... // Set the field arrays.
klass->SetSFieldsPtr(sfields);
DCHECK_EQ(klass->NumStaticFields(), num_sfields);
klass->SetIFieldsPtr(ifields);
DCHECK_EQ(klass->NumInstanceFields(), num_ifields);
// Load methods.
bool has_oat_class = false;
const OatFile::OatClass oat_class =
(Runtime::Current()->IsStarted() && !Runtime::Current()->IsAotCompiler())
? OatFile::FindOatClass(dex_file, klass->GetDexClassDefIndex(), &has_oat_class)
: OatFile::OatClass::Invalid();
const OatFile::OatClass* oat_class_ptr = has_oat_class ? &oat_class : nullptr;
klass->SetMethodsPtr(
AllocArtMethodArray(self, allocator, it.NumDirectMethods() + it.NumVirtualMethods()),
it.NumDirectMethods(),
it.NumVirtualMethods());
size_t class_def_method_index = 0;
uint32_t last_dex_method_index = DexFile::kDexNoIndex;
size_t last_class_def_method_index = 0;
// TODO These should really use the iterators.
for (size_t i = 0; it.HasNextDirectMethod(); i++, it.Next()) {
ArtMethod* method = klass->GetDirectMethodUnchecked(i, image_pointer_size_);
LoadMethod(dex_file, it, klass, method);
LinkCode(this, method, oat_class_ptr, class_def_method_index);
uint32_t it_method_index = it.GetMemberIndex();
if (last_dex_method_index == it_method_index) {
// duplicate case
method->SetMethodIndex(last_class_def_method_index);
} else {
method->SetMethodIndex(class_def_method_index);
last_dex_method_index = it_method_index;
last_class_def_method_index = class_def_method_index;
}
class_def_method_index++;
}
for (size_t i = 0; it.HasNextVirtualMethod(); i++, it.Next()) {
ArtMethod* method = klass->GetVirtualMethodUnchecked(i, image_pointer_size_);
LoadMethod(dex_file, it, klass, method);
DCHECK_EQ(class_def_method_index, it.NumDirectMethods() + i);
LinkCode(this, method, oat_class_ptr, class_def_method_index);
class_def_method_index++;
}
DCHECK(!it.HasNext());
}
// Ensure that the card is marked so that remembered sets pick up native roots.
Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(klass.Get());
self->AllowThreadSuspension();
}void ClassLinker::LoadClassMembers(Thread* self,const DexFile& dex_file,const uint8_t* class_data,Handle<mirror::Class> klass) {
{ // Note: We cannot have thread suspension until the field and method arrays are setup or else
// Class::VisitFieldRoots may miss some fields or methods.
ScopedAssertNoThreadSuspension nts(__FUNCTION__);
// Load static fields.
... for (; it.HasNextStaticField(); it.Next()) {
uint32_t field_idx = it.GetMemberIndex();
DCHECK_GE(field_idx, last_field_idx); // Ordering enforced by DexFileVerifier.
if (num_sfields == 0 || LIKELY(field_idx > last_field_idx)) {
DCHECK_LT(num_sfields, it.NumStaticFields());
LoadField(it, klass, &sfields->At(num_sfields));
++num_sfields;
last_field_idx = field_idx;
}
}
// Load instance fields.
LengthPrefixedArray<ArtField>* ifields = AllocArtFieldArray(self,allocator,it.NumInstanceFields());
size_t num_ifields = 0u;
last_field_idx = 0u;
for (; it.HasNextInstanceField(); it.Next()) {
uint32_t field_idx = it.GetMemberIndex();
DCHECK_GE(field_idx, last_field_idx); // Ordering enforced by DexFileVerifier.
if (num_ifields == 0 || LIKELY(field_idx > last_field_idx)) {
DCHECK_LT(num_ifields, it.NumInstanceFields());
LoadField(it, klass, &ifields->At(num_ifields));
++num_ifields;
last_field_idx = field_idx;
}
}
... // Set the field arrays.
klass->SetSFieldsPtr(sfields);
DCHECK_EQ(klass->NumStaticFields(), num_sfields);
klass->SetIFieldsPtr(ifields);
DCHECK_EQ(klass->NumInstanceFields(), num_ifields);
// Load methods.
bool has_oat_class = false;
const OatFile::OatClass oat_class =
(Runtime::Current()->IsStarted() && !Runtime::Current()->IsAotCompiler())
? OatFile::FindOatClass(dex_file, klass->GetDexClassDefIndex(), &has_oat_class)
: OatFile::OatClass::Invalid();
const OatFile::OatClass* oat_class_ptr = has_oat_class ? &oat_class : nullptr;
klass->SetMethodsPtr(
AllocArtMethodArray(self, allocator, it.NumDirectMethods() + it.NumVirtualMethods()),
it.NumDirectMethods(),
it.NumVirtualMethods());
size_t class_def_method_index = 0;
uint32_t last_dex_method_index = DexFile::kDexNoIndex;
size_t last_class_def_method_index = 0;
// TODO These should really use the iterators.
for (size_t i = 0; it.HasNextDirectMethod(); i++, it.Next()) {
ArtMethod* method = klass->GetDirectMethodUnchecked(i, image_pointer_size_);
LoadMethod(dex_file, it, klass, method);
LinkCode(this, method, oat_class_ptr, class_def_method_index);
uint32_t it_method_index = it.GetMemberIndex();
if (last_dex_method_index == it_method_index) {
// duplicate case
method->SetMethodIndex(last_class_def_method_index);
} else {
method->SetMethodIndex(class_def_method_index);
last_dex_method_index = it_method_index;
last_class_def_method_index = class_def_method_index;
}
class_def_method_index++;
}
for (size_t i = 0; it.HasNextVirtualMethod(); i++, it.Next()) {
ArtMethod* method = klass->GetVirtualMethodUnchecked(i, image_pointer_size_);
LoadMethod(dex_file, it, klass, method);
DCHECK_EQ(class_def_method_index, it.NumDirectMethods() + i);
LinkCode(this, method, oat_class_ptr, class_def_method_index);
class_def_method_index++;
}
DCHECK(!it.HasNext());
}
// Ensure that the card is marked so that remembered sets pick up native roots.
Runtime::Current()->GetHeap()->WriteBarrierEveryFieldOf(klass.Get());
self->AllowThreadSuspension();
}void ClassLinker::LoadMethod(const DexFile& dex_file,const ClassDataItemIterator& it,Handle<mirror::Class> klass,ArtMethod* dst) {
uint32_t dex_method_idx = it.GetMemberIndex();
const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx);
const char* method_name = dex_file.StringDataByIdx(method_id.name_idx_);
ScopedAssertNoThreadSuspension ants("LoadMethod");
dst->SetDexMethodIndex(dex_method_idx);
dst->SetDeclaringClass(klass.Get());
dst->SetCodeItemOffset(it.GetMethodCodeItemOffset());
dst->SetDexCacheResolvedMethods(klass->GetDexCache()->GetResolvedMethods(), image_pointer_size_);
uint32_t access_flags = it.GetMethodAccessFlags();
if (UNLIKELY(strcmp("finalize", method_name) == 0)) {
} else if (method_name[0] == '<') {
// Fix broken access flags for initializers. Bug 11157540.
bool is_init = (strcmp("<init>", method_name) == 0);
bool is_clinit = !is_init && (strcmp("<clinit>", method_name) == 0);
if (UNLIKELY(!is_init && !is_clinit)) {
LOG(WARNING) << "Unexpected '<' at start of method name " << method_name;
} else{
...
} }
dst->SetAccessFlags(access_flags);
}void ClassLinker::LoadMethod(const DexFile& dex_file,const ClassDataItemIterator& it,Handle<mirror::Class> klass,ArtMethod* dst) {
uint32_t dex_method_idx = it.GetMemberIndex();
const DexFile::MethodId& method_id = dex_file.GetMethodId(dex_method_idx);
const char* method_name = dex_file.StringDataByIdx(method_id.name_idx_);
ScopedAssertNoThreadSuspension ants("LoadMethod");
dst->SetDexMethodIndex(dex_method_idx);
dst->SetDeclaringClass(klass.Get());
dst->SetCodeItemOffset(it.GetMethodCodeItemOffset());
dst->SetDexCacheResolvedMethods(klass->GetDexCache()->GetResolvedMethods(), image_pointer_size_);
uint32_t access_flags = it.GetMethodAccessFlags();
if (UNLIKELY(strcmp("finalize", method_name) == 0)) {
} else if (method_name[0] == '<') {
// Fix broken access flags for initializers. Bug 11157540.
bool is_init = (strcmp("<init>", method_name) == 0);
bool is_clinit = !is_init && (strcmp("<clinit>", method_name) == 0);
if (UNLIKELY(!is_init && !is_clinit)) {
LOG(WARNING) << "Unexpected '<' at start of method name " << method_name;
} else{
...
} }
dst->SetAccessFlags(access_flags);
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最后于 2024-6-12 18:07
被mb_edqxbbqv编辑
，原因：
