openjdkjvmti/ti_search.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_search.h"

 #include "jni.h"

 #include "art_field-inl.h"
 #include "art_jvmti.h"
 #include "base/enums.h"
 #include "base/macros.h"
 #include "class_linker.h"
 #include "dex/art_dex_file_loader.h"
 #include "dex/dex_file.h"
 #include "dex/dex_file_loader.h"
 #include "jni/jni_internal.h"
 #include "mirror/class-inl.h"
 #include "mirror/object.h"
 #include "mirror/string.h"
 #include "nativehelper/scoped_local_ref.h"
 #include "obj_ptr-inl.h"
 #include "runtime.h"
 #include "runtime_callbacks.h"
 #include "scoped_thread_state_change-inl.h"
 #include "thread-current-inl.h"
 #include "thread_list.h"
 #include "ti_logging.h"
 #include "ti_phase.h"
 #include "well_known_classes.h"

 namespace openjdkjvmti {

 static std::vector<std::string> gSystemOnloadSegments;

 static art::ObjPtr<art::mirror::Object> GetSystemProperties(art::Thread* self,
                                                             art::ClassLinker* class_linker)
     REQUIRES_SHARED(art::Locks::mutator_lock_) {
   art::ObjPtr<art::mirror::Class> system_class =
       class_linker->LookupClass(self, "Ljava/lang/System;", nullptr);
   DCHECK(system_class != nullptr);
   DCHECK(system_class->IsInitialized());

   art::ArtField* props_field =
       system_class->FindDeclaredStaticField("props", "Ljava/util/Properties;");
   DCHECK(props_field != nullptr);

   art::ObjPtr<art::mirror::Object> props_obj = props_field->GetObject(system_class);
   DCHECK(props_obj != nullptr);

   return props_obj;
 }

 static void Update() REQUIRES_SHARED(art::Locks::mutator_lock_) {
   if (gSystemOnloadSegments.empty()) {
     return;
   }

   // In the on-load phase we have to modify java.class.path to influence the system classloader.
   // As this is an unmodifiable system property, we have to access the "defaults" field.
   art::ClassLinker* class_linker = art::Runtime::Current()->GetClassLinker();
   DCHECK(class_linker != nullptr);
   art::Thread* self = art::Thread::Current();

   // Prepare: collect classes, fields and methods.
   art::ObjPtr<art::mirror::Class> properties_class =
       class_linker->LookupClass(self, "Ljava/util/Properties;", nullptr);
   DCHECK(properties_class != nullptr);

   ScopedLocalRef<jobject> defaults_jobj(self->GetJniEnv(), nullptr);
   {
     art::ObjPtr<art::mirror::Object> props_obj = GetSystemProperties(self, class_linker);

     art::ArtField* defaults_field =
         properties_class->FindDeclaredInstanceField("defaults", "Ljava/util/Properties;");
     DCHECK(defaults_field != nullptr);

     art::ObjPtr<art::mirror::Object> defaults_obj = defaults_field->GetObject(props_obj);
     DCHECK(defaults_obj != nullptr);
     defaults_jobj.reset(self->GetJniEnv()->AddLocalReference<jobject>(defaults_obj));
   }

   art::ArtMethod* get_property =
       properties_class->FindClassMethod(
           "getProperty",
           "(Ljava/lang/String;)Ljava/lang/String;",
           art::kRuntimePointerSize);
   DCHECK(get_property != nullptr);
   DCHECK(!get_property->IsDirect());
   DCHECK(get_property->GetDeclaringClass() == properties_class);
   art::ArtMethod* set_property =
       properties_class->FindClassMethod(
           "setProperty",
           "(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/Object;",
           art::kRuntimePointerSize);
   DCHECK(set_property != nullptr);
   DCHECK(!set_property->IsDirect());
   DCHECK(set_property->GetDeclaringClass() == properties_class);

   // This is an allocation. Do this late to avoid the need for handles.
   ScopedLocalRef<jobject> cp_jobj(self->GetJniEnv(), nullptr);
   {
     art::ObjPtr<art::mirror::Object> cp_key =
         art::mirror::String::AllocFromModifiedUtf8(self, "java.class.path");
     if (cp_key == nullptr) {
       self->AssertPendingOOMException();
       self->ClearException();
       return;
     }
     cp_jobj.reset(self->GetJniEnv()->AddLocalReference<jobject>(cp_key));
   }

   // OK, now get the current value.
   std::string str_value;
   {
     ScopedLocalRef<jobject> old_value(self->GetJniEnv(),
                                       self->GetJniEnv()->CallObjectMethod(
                                           defaults_jobj.get(),
                                           art::jni::EncodeArtMethod(get_property),
                                           cp_jobj.get()));
     DCHECK(old_value.get() != nullptr);

     str_value = self->DecodeJObject(old_value.get())->AsString()->ToModifiedUtf8();
     self->GetJniEnv()->DeleteLocalRef(old_value.release());
   }

   // Update the value by appending the new segments.
   for (const std::string& segment : gSystemOnloadSegments) {
     if (!str_value.empty()) {
       str_value += ":";
     }
     str_value += segment;
   }
   gSystemOnloadSegments.clear();

   // Create the new value object.
   ScopedLocalRef<jobject> new_val_jobj(self->GetJniEnv(), nullptr);
   {
     art::ObjPtr<art::mirror::Object> new_value =
         art::mirror::String::AllocFromModifiedUtf8(self, str_value.c_str());
     if (new_value == nullptr) {
       self->AssertPendingOOMException();
       self->ClearException();
       return;
     }

     new_val_jobj.reset(self->GetJniEnv()->AddLocalReference<jobject>(new_value));
   }

   // Write to the defaults.
   ScopedLocalRef<jobject> res_obj(self->GetJniEnv(),
                                   self->GetJniEnv()->CallObjectMethod(defaults_jobj.get(),
                                       art::jni::EncodeArtMethod(set_property),
                                       cp_jobj.get(),
                                       new_val_jobj.get()));
   if (self->IsExceptionPending()) {
     self->ClearException();
     return;
   }
 }

 struct SearchCallback : public art::RuntimePhaseCallback {
   void NextRuntimePhase(RuntimePhase phase) override REQUIRES_SHARED(art::Locks::mutator_lock_) {
     if (phase == RuntimePhase::kStart) {
       // It's time to update the system properties.
       Update();
     }
   }
 };

 static SearchCallback gSearchCallback;

 void SearchUtil::Register() {
   art::Runtime* runtime = art::Runtime::Current();

   art::ScopedThreadStateChange stsc(art::Thread::Current(),
                                     art::ThreadState::kWaitingForDebuggerToAttach);
   art::ScopedSuspendAll ssa("Add search callback");
   runtime->GetRuntimeCallbacks()->AddRuntimePhaseCallback(&gSearchCallback);
 }

 void SearchUtil::Unregister() {
   art::ScopedThreadStateChange stsc(art::Thread::Current(),
                                     art::ThreadState::kWaitingForDebuggerToAttach);
   art::ScopedSuspendAll ssa("Remove search callback");
   art::Runtime* runtime = art::Runtime::Current();
   runtime->GetRuntimeCallbacks()->RemoveRuntimePhaseCallback(&gSearchCallback);
 }

 jvmtiError SearchUtil::AddToBootstrapClassLoaderSearch(jvmtiEnv* env,
                                                        const char* segment) {
   art::Runtime* current = art::Runtime::Current();
   if (current == nullptr) {
     return ERR(WRONG_PHASE);
   }
   if (current->GetClassLinker() == nullptr) {
     return ERR(WRONG_PHASE);
   }
   if (segment == nullptr) {
     return ERR(NULL_POINTER);
   }

   std::string error_msg;
   std::vector<std::unique_ptr<const art::DexFile>> dex_files;
   const art::ArtDexFileLoader dex_file_loader;
   if (!dex_file_loader.Open(segment,
                             segment,
                             /* verify= */ true,
                             /* verify_checksum= */ true,
                             &error_msg,
                             &dex_files)) {
     JVMTI_LOG(WARNING, env) << "Could not open " << segment << " for boot classpath extension: "
                             << error_msg;
     return ERR(ILLEGAL_ARGUMENT);
   }

   art::ScopedObjectAccess soa(art::Thread::Current());
   for (std::unique_ptr<const art::DexFile>& dex_file : dex_files) {
     current->GetClassLinker()->AppendToBootClassPath(art::Thread::Current(), *dex_file.release());
   }

   return ERR(NONE);
 }

 jvmtiError SearchUtil::AddToSystemClassLoaderSearch(jvmtiEnv* jvmti_env ATTRIBUTE_UNUSED,
                                                     const char* segment) {
   if (segment == nullptr) {
     return ERR(NULL_POINTER);
   }

   jvmtiPhase phase = PhaseUtil::GetPhaseUnchecked();

   if (phase == jvmtiPhase::JVMTI_PHASE_ONLOAD) {
     // We could try and see whether it is a valid path. We could also try to allocate Java
     // objects to avoid later OOME.
     gSystemOnloadSegments.push_back(segment);
     return ERR(NONE);
   } else if (phase != jvmtiPhase::JVMTI_PHASE_LIVE) {
     return ERR(WRONG_PHASE);
   }

   jobject sys_class_loader = art::Runtime::Current()->GetSystemClassLoader();
   if (sys_class_loader == nullptr) {
     // This is unexpected.
     return ERR(INTERNAL);
   }

   // We'll use BaseDexClassLoader.addDexPath, as it takes care of array resizing etc. As a downside,
   // exceptions are swallowed.

   art::Thread* self = art::Thread::Current();
   JNIEnv* env = self->GetJniEnv();
   if (!env->IsInstanceOf(sys_class_loader,
                          art::WellKnownClasses::dalvik_system_BaseDexClassLoader)) {
     return ERR(INTERNAL);
   }

   jmethodID add_dex_path_id = env->GetMethodID(
       art::WellKnownClasses::dalvik_system_BaseDexClassLoader,
       "addDexPath",
       "(Ljava/lang/String;)V");
   if (add_dex_path_id == nullptr) {
     return ERR(INTERNAL);
   }

   ScopedLocalRef<jstring> dex_path(env, env->NewStringUTF(segment));
   if (dex_path.get() == nullptr) {
     return ERR(INTERNAL);
   }
   env->CallVoidMethod(sys_class_loader, add_dex_path_id, dex_path.get());

   if (env->ExceptionCheck()) {
     env->ExceptionClear();
     return ERR(ILLEGAL_ARGUMENT);
   }
   return ERR(NONE);
 }

 }  // 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_search.h"

	#include "jni.h"

	#include "art_field-inl.h"
	#include "art_jvmti.h"
	#include "base/enums.h"
	#include "base/macros.h"
	#include "class_linker.h"
	#include "dex/art_dex_file_loader.h"
	#include "dex/dex_file.h"
	#include "dex/dex_file_loader.h"
	#include "jni/jni_internal.h"
	#include "mirror/class-inl.h"
	#include "mirror/object.h"
	#include "mirror/string.h"
	#include "nativehelper/scoped_local_ref.h"
	#include "obj_ptr-inl.h"
	#include "runtime.h"
	#include "runtime_callbacks.h"
	#include "scoped_thread_state_change-inl.h"
	#include "thread-current-inl.h"
	#include "thread_list.h"
	#include "ti_logging.h"
	#include "ti_phase.h"
	#include "well_known_classes.h"

	namespace openjdkjvmti {

	static std::vector<std::string> gSystemOnloadSegments;

	static art::ObjPtr<art::mirror::Object> GetSystemProperties(art::Thread* self,
	art::ClassLinker* class_linker)
	REQUIRES_SHARED(art::Locks::mutator_lock_) {
	art::ObjPtr<art::mirror::Class> system_class =
	class_linker->LookupClass(self, "Ljava/lang/System;", nullptr);
	DCHECK(system_class != nullptr);
	DCHECK(system_class->IsInitialized());

	art::ArtField* props_field =
	system_class->FindDeclaredStaticField("props", "Ljava/util/Properties;");
	DCHECK(props_field != nullptr);

	art::ObjPtr<art::mirror::Object> props_obj = props_field->GetObject(system_class);
	DCHECK(props_obj != nullptr);

	return props_obj;
	}

	static void Update() REQUIRES_SHARED(art::Locks::mutator_lock_) {
	if (gSystemOnloadSegments.empty()) {
	return;
	}

	// In the on-load phase we have to modify java.class.path to influence the system classloader.
	// As this is an unmodifiable system property, we have to access the "defaults" field.
	art::ClassLinker* class_linker = art::Runtime::Current()->GetClassLinker();
	DCHECK(class_linker != nullptr);
	art::Thread* self = art::Thread::Current();

	// Prepare: collect classes, fields and methods.
	art::ObjPtr<art::mirror::Class> properties_class =
	class_linker->LookupClass(self, "Ljava/util/Properties;", nullptr);
	DCHECK(properties_class != nullptr);

	ScopedLocalRef<jobject> defaults_jobj(self->GetJniEnv(), nullptr);
	{
	art::ObjPtr<art::mirror::Object> props_obj = GetSystemProperties(self, class_linker);

	art::ArtField* defaults_field =
	properties_class->FindDeclaredInstanceField("defaults", "Ljava/util/Properties;");
	DCHECK(defaults_field != nullptr);

	art::ObjPtr<art::mirror::Object> defaults_obj = defaults_field->GetObject(props_obj);
	DCHECK(defaults_obj != nullptr);
	defaults_jobj.reset(self->GetJniEnv()->AddLocalReference<jobject>(defaults_obj));
	}

	art::ArtMethod* get_property =
	properties_class->FindClassMethod(
	"getProperty",
	"(Ljava/lang/String;)Ljava/lang/String;",
	art::kRuntimePointerSize);
	DCHECK(get_property != nullptr);
	DCHECK(!get_property->IsDirect());
	DCHECK(get_property->GetDeclaringClass() == properties_class);
	art::ArtMethod* set_property =
	properties_class->FindClassMethod(
	"setProperty",
	"(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/Object;",
	art::kRuntimePointerSize);
	DCHECK(set_property != nullptr);
	DCHECK(!set_property->IsDirect());
	DCHECK(set_property->GetDeclaringClass() == properties_class);

	// This is an allocation. Do this late to avoid the need for handles.
	ScopedLocalRef<jobject> cp_jobj(self->GetJniEnv(), nullptr);
	{
	art::ObjPtr<art::mirror::Object> cp_key =
	art::mirror::String::AllocFromModifiedUtf8(self, "java.class.path");
	if (cp_key == nullptr) {
	self->AssertPendingOOMException();
	self->ClearException();
	return;
	}
	cp_jobj.reset(self->GetJniEnv()->AddLocalReference<jobject>(cp_key));
	}

	// OK, now get the current value.
	std::string str_value;
	{
	ScopedLocalRef<jobject> old_value(self->GetJniEnv(),
	self->GetJniEnv()->CallObjectMethod(
	defaults_jobj.get(),
	art::jni::EncodeArtMethod(get_property),
	cp_jobj.get()));
	DCHECK(old_value.get() != nullptr);

	str_value = self->DecodeJObject(old_value.get())->AsString()->ToModifiedUtf8();
	self->GetJniEnv()->DeleteLocalRef(old_value.release());
	}

	// Update the value by appending the new segments.
	for (const std::string& segment : gSystemOnloadSegments) {
	if (!str_value.empty()) {
	str_value += ":";
	}
	str_value += segment;
	}
	gSystemOnloadSegments.clear();

	// Create the new value object.
	ScopedLocalRef<jobject> new_val_jobj(self->GetJniEnv(), nullptr);
	{
	art::ObjPtr<art::mirror::Object> new_value =
	art::mirror::String::AllocFromModifiedUtf8(self, str_value.c_str());
	if (new_value == nullptr) {
	self->AssertPendingOOMException();
	self->ClearException();
	return;
	}

	new_val_jobj.reset(self->GetJniEnv()->AddLocalReference<jobject>(new_value));
	}

	// Write to the defaults.
	ScopedLocalRef<jobject> res_obj(self->GetJniEnv(),
	self->GetJniEnv()->CallObjectMethod(defaults_jobj.get(),
	art::jni::EncodeArtMethod(set_property),
	cp_jobj.get(),
	new_val_jobj.get()));
	if (self->IsExceptionPending()) {
	self->ClearException();
	return;
	}
	}

	struct SearchCallback : public art::RuntimePhaseCallback {
	void NextRuntimePhase(RuntimePhase phase) override REQUIRES_SHARED(art::Locks::mutator_lock_) {
	if (phase == RuntimePhase::kStart) {
	// It's time to update the system properties.
	Update();
	}
	}
	};

	static SearchCallback gSearchCallback;

	void SearchUtil::Register() {
	art::Runtime* runtime = art::Runtime::Current();

	art::ScopedThreadStateChange stsc(art::Thread::Current(),
	art::ThreadState::kWaitingForDebuggerToAttach);
	art::ScopedSuspendAll ssa("Add search callback");
	runtime->GetRuntimeCallbacks()->AddRuntimePhaseCallback(&gSearchCallback);
	}

	void SearchUtil::Unregister() {
	art::ScopedThreadStateChange stsc(art::Thread::Current(),
	art::ThreadState::kWaitingForDebuggerToAttach);
	art::ScopedSuspendAll ssa("Remove search callback");
	art::Runtime* runtime = art::Runtime::Current();
	runtime->GetRuntimeCallbacks()->RemoveRuntimePhaseCallback(&gSearchCallback);
	}

	jvmtiError SearchUtil::AddToBootstrapClassLoaderSearch(jvmtiEnv* env,
	const char* segment) {
	art::Runtime* current = art::Runtime::Current();
	if (current == nullptr) {
	return ERR(WRONG_PHASE);
	}
	if (current->GetClassLinker() == nullptr) {
	return ERR(WRONG_PHASE);
	}
	if (segment == nullptr) {
	return ERR(NULL_POINTER);
	}

	std::string error_msg;
	std::vector<std::unique_ptr<const art::DexFile>> dex_files;
	const art::ArtDexFileLoader dex_file_loader;
	if (!dex_file_loader.Open(segment,
	segment,
	/* verify= */ true,
	/* verify_checksum= */ true,
	&error_msg,
	&dex_files)) {
	JVMTI_LOG(WARNING, env) << "Could not open " << segment << " for boot classpath extension: "
	<< error_msg;
	return ERR(ILLEGAL_ARGUMENT);
	}

	art::ScopedObjectAccess soa(art::Thread::Current());
	for (std::unique_ptr<const art::DexFile>& dex_file : dex_files) {
	current->GetClassLinker()->AppendToBootClassPath(art::Thread::Current(), *dex_file.release());
	}

	return ERR(NONE);
	}

	jvmtiError SearchUtil::AddToSystemClassLoaderSearch(jvmtiEnv* jvmti_env ATTRIBUTE_UNUSED,
	const char* segment) {
	if (segment == nullptr) {
	return ERR(NULL_POINTER);
	}

	jvmtiPhase phase = PhaseUtil::GetPhaseUnchecked();

	if (phase == jvmtiPhase::JVMTI_PHASE_ONLOAD) {
	// We could try and see whether it is a valid path. We could also try to allocate Java
	// objects to avoid later OOME.
	gSystemOnloadSegments.push_back(segment);
	return ERR(NONE);
	} else if (phase != jvmtiPhase::JVMTI_PHASE_LIVE) {
	return ERR(WRONG_PHASE);
	}

	jobject sys_class_loader = art::Runtime::Current()->GetSystemClassLoader();
	if (sys_class_loader == nullptr) {
	// This is unexpected.
	return ERR(INTERNAL);
	}

	// We'll use BaseDexClassLoader.addDexPath, as it takes care of array resizing etc. As a downside,
	// exceptions are swallowed.

	art::Thread* self = art::Thread::Current();
	JNIEnv* env = self->GetJniEnv();
	if (!env->IsInstanceOf(sys_class_loader,
	art::WellKnownClasses::dalvik_system_BaseDexClassLoader)) {
	return ERR(INTERNAL);
	}

	jmethodID add_dex_path_id = env->GetMethodID(
	art::WellKnownClasses::dalvik_system_BaseDexClassLoader,
	"addDexPath",
	"(Ljava/lang/String;)V");
	if (add_dex_path_id == nullptr) {
	return ERR(INTERNAL);
	}

	ScopedLocalRef<jstring> dex_path(env, env->NewStringUTF(segment));
	if (dex_path.get() == nullptr) {
	return ERR(INTERNAL);
	}
	env->CallVoidMethod(sys_class_loader, add_dex_path_id, dex_path.get());

	if (env->ExceptionCheck()) {
	env->ExceptionClear();
	return ERR(ILLEGAL_ARGUMENT);
	}
	return ERR(NONE);
	}

	} // namespace openjdkjvmti