openjdkjvmti/ti_class_loader.cc - platform/art - Git at Google

 /* Copyright (C) 2017 The Android Open Source Project
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This file implements interfaces from the file jvmti.h. This implementation
  * is licensed under the same terms as the file jvmti.h.  The
  * copyright and license information for the file jvmti.h follows.
  *
  * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */

 #include "ti_class_loader-inl.h"

 #include <limits>

 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>

 #include "art_field-inl.h"
 #include "art_jvmti.h"
 #include "dex/dex_file.h"
 #include "dex/dex_file_types.h"
 #include "events-inl.h"
 #include "gc/allocation_listener.h"
 #include "gc/heap.h"
 #include "instrumentation.h"
 #include "jit/jit.h"
 #include "jit/jit_code_cache.h"
 #include "jni/jni_env_ext-inl.h"
 #include "jvmti_allocator.h"
 #include "mirror/array-alloc-inl.h"
 #include "mirror/array-inl.h"
 #include "mirror/class.h"
 #include "mirror/class_ext.h"
 #include "mirror/object.h"
 #include "nativehelper/scoped_local_ref.h"
 #include "object_lock.h"
 #include "runtime.h"
 #include "transform.h"

 namespace openjdkjvmti {

 bool ClassLoaderHelper::AddToClassLoader(art::Thread* self,
                                          art::Handle<art::mirror::ClassLoader> loader,
                                          const art::DexFile* dex_file) {
   art::ScopedObjectAccessUnchecked soa(self);
   art::StackHandleScope<3> hs(self);
   if (art::ClassLinker::IsBootClassLoader(soa, loader.Get())) {
     art::Runtime::Current()->GetClassLinker()->AppendToBootClassPath(self, *dex_file);
     return true;
   }
   art::Handle<art::mirror::Object> java_dex_file_obj(
       hs.NewHandle(FindSourceDexFileObject(self, loader)));
   if (java_dex_file_obj.IsNull()) {
     return false;
   }
   art::Handle<art::mirror::LongArray> old_cookie(hs.NewHandle(GetDexFileCookie(java_dex_file_obj)));
   art::Handle<art::mirror::LongArray> cookie(hs.NewHandle(
       AllocateNewDexFileCookie(self, old_cookie, dex_file)));
   if (cookie.IsNull()) {
     return false;
   }
   art::ScopedAssertNoThreadSuspension nts("Replacing cookie fields in j.l.DexFile object");
   UpdateJavaDexFile(java_dex_file_obj.Get(), cookie.Get());
   return true;
 }

 void ClassLoaderHelper::UpdateJavaDexFile(art::ObjPtr<art::mirror::Object> java_dex_file,
                                           art::ObjPtr<art::mirror::LongArray> new_cookie) {
   art::ArtField* internal_cookie_field = java_dex_file->GetClass()->FindDeclaredInstanceField(
       "mInternalCookie", "Ljava/lang/Object;");
   art::ArtField* cookie_field = java_dex_file->GetClass()->FindDeclaredInstanceField(
       "mCookie", "Ljava/lang/Object;");
   CHECK(internal_cookie_field != nullptr);
   art::ObjPtr<art::mirror::LongArray> orig_internal_cookie(
       internal_cookie_field->GetObject(java_dex_file)->AsLongArray());
   art::ObjPtr<art::mirror::LongArray> orig_cookie(
       cookie_field->GetObject(java_dex_file)->AsLongArray());
   internal_cookie_field->SetObject<false>(java_dex_file, new_cookie);
   if (!orig_cookie.IsNull()) {
     cookie_field->SetObject<false>(java_dex_file, new_cookie);
   }
 }

 art::ObjPtr<art::mirror::LongArray> ClassLoaderHelper::GetDexFileCookie(
     art::Handle<art::mirror::Object> java_dex_file_obj) {
   // mCookie is nulled out if the DexFile has been closed but mInternalCookie sticks around until
   // the object is finalized. Since they always point to the same array if mCookie is not null we
   // just use the mInternalCookie field. We will update one or both of these fields later.
   art::ArtField* internal_cookie_field = java_dex_file_obj->GetClass()->FindDeclaredInstanceField(
       "mInternalCookie", "Ljava/lang/Object;");
   // TODO Add check that mCookie is either null or same as mInternalCookie
   CHECK(internal_cookie_field != nullptr);
   return internal_cookie_field->GetObject(java_dex_file_obj.Get())->AsLongArray();
 }

 art::ObjPtr<art::mirror::LongArray> ClassLoaderHelper::AllocateNewDexFileCookie(
     art::Thread* self,
     art::Handle<art::mirror::LongArray> cookie,
     const art::DexFile* dex_file) {
   art::StackHandleScope<1> hs(self);
   CHECK(cookie != nullptr);
   CHECK_GE(cookie->GetLength(), 1);
   art::Handle<art::mirror::LongArray> new_cookie(
       hs.NewHandle(art::mirror::LongArray::Alloc(self, cookie->GetLength() + 1)));
   if (new_cookie == nullptr) {
     self->AssertPendingOOMException();
     return nullptr;
   }
   // Copy the oat-dex field at the start.
   new_cookie->SetWithoutChecks<false>(0, cookie->GetWithoutChecks(0));
   // This must match the casts in runtime/native/dalvik_system_DexFile.cc:ConvertDexFilesToJavaArray
   new_cookie->SetWithoutChecks<false>(
       1, static_cast<int64_t>(reinterpret_cast<uintptr_t>(dex_file)));
   new_cookie->Memcpy(2, cookie.Get(), 1, cookie->GetLength() - 1);
   return new_cookie.Get();
 }

 art::ObjPtr<art::mirror::ObjectArray<art::mirror::Object>> ClassLoaderHelper::GetDexElementList(
     art::Thread* self,
     art::Handle<art::mirror::ClassLoader> loader) {
   art::StackHandleScope<4> hs(self);

   art::Handle<art::mirror::Class>
       base_dex_loader_class(hs.NewHandle(self->DecodeJObject(
           art::WellKnownClasses::dalvik_system_BaseDexClassLoader)->AsClass()));

   // Get all the ArtFields so we can look in the BaseDexClassLoader
   art::ArtField* path_list_field = art::jni::DecodeArtField(
       art::WellKnownClasses::dalvik_system_BaseDexClassLoader_pathList);
   art::ArtField* dex_path_list_element_field =
       art::jni::DecodeArtField(art::WellKnownClasses::dalvik_system_DexPathList_dexElements);

   // Check if loader is a BaseDexClassLoader
   art::Handle<art::mirror::Class> loader_class(hs.NewHandle(loader->GetClass()));
   // Currently only base_dex_loader is allowed to actually define classes but if this changes in the
   // future we should make sure to support all class loader types.
   if (!loader_class->IsSubClass(base_dex_loader_class.Get())) {
     LOG(ERROR) << "The classloader " << loader_class->PrettyClass() << " is not a "
                << base_dex_loader_class->PrettyClass() << " which is currently the only "
                << "supported class loader type!";
     return nullptr;
   }
   // Start navigating the fields of the loader (now known to be a BaseDexClassLoader derivative)
   art::Handle<art::mirror::Object> path_list(
       hs.NewHandle(path_list_field->GetObject(loader.Get())));
   CHECK(path_list != nullptr);
   art::ObjPtr<art::mirror::ObjectArray<art::mirror::Object>> dex_elements_list =
       dex_path_list_element_field->GetObject(path_list.Get())->AsObjectArray<art::mirror::Object>();
   return dex_elements_list;
 }

 // TODO This should return the actual source java.lang.DexFile object for the klass being loaded.
 art::ObjPtr<art::mirror::Object> ClassLoaderHelper::FindSourceDexFileObject(
     art::Thread* self, art::Handle<art::mirror::ClassLoader> loader) {
   art::ObjPtr<art::mirror::Object> res = nullptr;
   VisitDexFileObjects(self,
                       loader,
                       [&] (art::ObjPtr<art::mirror::Object> dex_file) {
                         res = dex_file;
                         // Just stop at the first one.
                         // TODO It would be cleaner to put the art::DexFile into the
                         // dalvik.system.DexFile the class comes from but it is more annoying
                         // because we would need to find this class. It is not necessary for proper
                         // function since we just need to be in front of the classes old dex file in
                         // the path.
                         return false;
                       });
   return res;
 }

 }  // namespace openjdkjvmti
	/* Copyright (C) 2017 The Android Open Source Project
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This file implements interfaces from the file jvmti.h. This implementation
	* is licensed under the same terms as the file jvmti.h. The
	* copyright and license information for the file jvmti.h follows.
	*
	* Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	#include "ti_class_loader-inl.h"

	#include <limits>

	#include <android-base/logging.h>
	#include <android-base/stringprintf.h>

	#include "art_field-inl.h"
	#include "art_jvmti.h"
	#include "dex/dex_file.h"
	#include "dex/dex_file_types.h"
	#include "events-inl.h"
	#include "gc/allocation_listener.h"
	#include "gc/heap.h"
	#include "instrumentation.h"
	#include "jit/jit.h"
	#include "jit/jit_code_cache.h"
	#include "jni/jni_env_ext-inl.h"
	#include "jvmti_allocator.h"
	#include "mirror/array-alloc-inl.h"
	#include "mirror/array-inl.h"
	#include "mirror/class.h"
	#include "mirror/class_ext.h"
	#include "mirror/object.h"
	#include "nativehelper/scoped_local_ref.h"
	#include "object_lock.h"
	#include "runtime.h"
	#include "transform.h"

	namespace openjdkjvmti {

	bool ClassLoaderHelper::AddToClassLoader(art::Thread* self,
	art::Handle<art::mirror::ClassLoader> loader,
	const art::DexFile* dex_file) {
	art::ScopedObjectAccessUnchecked soa(self);
	art::StackHandleScope<3> hs(self);
	if (art::ClassLinker::IsBootClassLoader(soa, loader.Get())) {
	art::Runtime::Current()->GetClassLinker()->AppendToBootClassPath(self, *dex_file);
	return true;
	}
	art::Handle<art::mirror::Object> java_dex_file_obj(
	hs.NewHandle(FindSourceDexFileObject(self, loader)));
	if (java_dex_file_obj.IsNull()) {
	return false;
	}
	art::Handle<art::mirror::LongArray> old_cookie(hs.NewHandle(GetDexFileCookie(java_dex_file_obj)));
	art::Handle<art::mirror::LongArray> cookie(hs.NewHandle(
	AllocateNewDexFileCookie(self, old_cookie, dex_file)));
	if (cookie.IsNull()) {
	return false;
	}
	art::ScopedAssertNoThreadSuspension nts("Replacing cookie fields in j.l.DexFile object");
	UpdateJavaDexFile(java_dex_file_obj.Get(), cookie.Get());
	return true;
	}

	void ClassLoaderHelper::UpdateJavaDexFile(art::ObjPtr<art::mirror::Object> java_dex_file,
	art::ObjPtr<art::mirror::LongArray> new_cookie) {
	art::ArtField* internal_cookie_field = java_dex_file->GetClass()->FindDeclaredInstanceField(
	"mInternalCookie", "Ljava/lang/Object;");
	art::ArtField* cookie_field = java_dex_file->GetClass()->FindDeclaredInstanceField(
	"mCookie", "Ljava/lang/Object;");
	CHECK(internal_cookie_field != nullptr);
	art::ObjPtr<art::mirror::LongArray> orig_internal_cookie(
	internal_cookie_field->GetObject(java_dex_file)->AsLongArray());
	art::ObjPtr<art::mirror::LongArray> orig_cookie(
	cookie_field->GetObject(java_dex_file)->AsLongArray());
	internal_cookie_field->SetObject<false>(java_dex_file, new_cookie);
	if (!orig_cookie.IsNull()) {
	cookie_field->SetObject<false>(java_dex_file, new_cookie);
	}
	}

	art::ObjPtr<art::mirror::LongArray> ClassLoaderHelper::GetDexFileCookie(
	art::Handle<art::mirror::Object> java_dex_file_obj) {
	// mCookie is nulled out if the DexFile has been closed but mInternalCookie sticks around until
	// the object is finalized. Since they always point to the same array if mCookie is not null we
	// just use the mInternalCookie field. We will update one or both of these fields later.
	art::ArtField* internal_cookie_field = java_dex_file_obj->GetClass()->FindDeclaredInstanceField(
	"mInternalCookie", "Ljava/lang/Object;");
	// TODO Add check that mCookie is either null or same as mInternalCookie
	CHECK(internal_cookie_field != nullptr);
	return internal_cookie_field->GetObject(java_dex_file_obj.Get())->AsLongArray();
	}

	art::ObjPtr<art::mirror::LongArray> ClassLoaderHelper::AllocateNewDexFileCookie(
	art::Thread* self,
	art::Handle<art::mirror::LongArray> cookie,
	const art::DexFile* dex_file) {
	art::StackHandleScope<1> hs(self);
	CHECK(cookie != nullptr);
	CHECK_GE(cookie->GetLength(), 1);
	art::Handle<art::mirror::LongArray> new_cookie(
	hs.NewHandle(art::mirror::LongArray::Alloc(self, cookie->GetLength() + 1)));
	if (new_cookie == nullptr) {
	self->AssertPendingOOMException();
	return nullptr;
	}
	// Copy the oat-dex field at the start.
	new_cookie->SetWithoutChecks<false>(0, cookie->GetWithoutChecks(0));
	// This must match the casts in runtime/native/dalvik_system_DexFile.cc:ConvertDexFilesToJavaArray
	new_cookie->SetWithoutChecks<false>(
	1, static_cast<int64_t>(reinterpret_cast<uintptr_t>(dex_file)));
	new_cookie->Memcpy(2, cookie.Get(), 1, cookie->GetLength() - 1);
	return new_cookie.Get();
	}

	art::ObjPtr<art::mirror::ObjectArray<art::mirror::Object>> ClassLoaderHelper::GetDexElementList(
	art::Thread* self,
	art::Handle<art::mirror::ClassLoader> loader) {
	art::StackHandleScope<4> hs(self);

	art::Handle<art::mirror::Class>
	base_dex_loader_class(hs.NewHandle(self->DecodeJObject(
	art::WellKnownClasses::dalvik_system_BaseDexClassLoader)->AsClass()));

	// Get all the ArtFields so we can look in the BaseDexClassLoader
	art::ArtField* path_list_field = art::jni::DecodeArtField(
	art::WellKnownClasses::dalvik_system_BaseDexClassLoader_pathList);
	art::ArtField* dex_path_list_element_field =
	art::jni::DecodeArtField(art::WellKnownClasses::dalvik_system_DexPathList_dexElements);

	// Check if loader is a BaseDexClassLoader
	art::Handle<art::mirror::Class> loader_class(hs.NewHandle(loader->GetClass()));
	// Currently only base_dex_loader is allowed to actually define classes but if this changes in the
	// future we should make sure to support all class loader types.
	if (!loader_class->IsSubClass(base_dex_loader_class.Get())) {
	LOG(ERROR) << "The classloader " << loader_class->PrettyClass() << " is not a "
	<< base_dex_loader_class->PrettyClass() << " which is currently the only "
	<< "supported class loader type!";
	return nullptr;
	}
	// Start navigating the fields of the loader (now known to be a BaseDexClassLoader derivative)
	art::Handle<art::mirror::Object> path_list(
	hs.NewHandle(path_list_field->GetObject(loader.Get())));
	CHECK(path_list != nullptr);
	art::ObjPtr<art::mirror::ObjectArray<art::mirror::Object>> dex_elements_list =
	dex_path_list_element_field->GetObject(path_list.Get())->AsObjectArray<art::mirror::Object>();
	return dex_elements_list;
	}

	// TODO This should return the actual source java.lang.DexFile object for the klass being loaded.
	art::ObjPtr<art::mirror::Object> ClassLoaderHelper::FindSourceDexFileObject(
	art::Thread* self, art::Handle<art::mirror::ClassLoader> loader) {
	art::ObjPtr<art::mirror::Object> res = nullptr;
	VisitDexFileObjects(self,
	loader,
	[&] (art::ObjPtr<art::mirror::Object> dex_file) {
	res = dex_file;
	// Just stop at the first one.
	// TODO It would be cleaner to put the art::DexFile into the
	// dalvik.system.DexFile the class comes from but it is more annoying
	// because we would need to find this class. It is not necessary for proper
	// function since we just need to be in front of the classes old dex file in
	// the path.
	return false;
	});
	return res;
	}

	} // namespace openjdkjvmti