ART: Add OnLoad system classloader search support
Add support for extension of the system classloader search path
during the OnLoad phase. Add test.
Bug: 34359699
Test: m test-art-host-run-test-936-search-onload
Change-Id: Ie0a5b4bb77999dfae87f955dde40b73ffe053b8e
diff --git a/runtime/openjdkjvmti/OpenjdkJvmTi.cc b/runtime/openjdkjvmti/OpenjdkJvmTi.cc
index c0c301f..a815a60 100644
--- a/runtime/openjdkjvmti/OpenjdkJvmTi.cc
+++ b/runtime/openjdkjvmti/OpenjdkJvmTi.cc
@@ -1368,6 +1368,7 @@
ThreadUtil::Register(&gEventHandler);
ClassUtil::Register(&gEventHandler);
DumpUtil::Register(&gEventHandler);
+ SearchUtil::Register();
runtime->GetJavaVM()->AddEnvironmentHook(GetEnvHandler);
runtime->AddSystemWeakHolder(&gObjectTagTable);
@@ -1380,6 +1381,7 @@
ThreadUtil::Unregister();
ClassUtil::Unregister();
DumpUtil::Unregister();
+ SearchUtil::Unregister();
return true;
}
diff --git a/runtime/openjdkjvmti/ti_phase.cc b/runtime/openjdkjvmti/ti_phase.cc
index 4970288..60371cf 100644
--- a/runtime/openjdkjvmti/ti_phase.cc
+++ b/runtime/openjdkjvmti/ti_phase.cc
@@ -136,4 +136,8 @@
art::Runtime::Current()->GetRuntimeCallbacks()->RemoveRuntimePhaseCallback(&gPhaseCallback);
}
+jvmtiPhase PhaseUtil::GetPhaseUnchecked() {
+ return PhaseUtil::current_phase_;
+}
+
} // namespace openjdkjvmti
diff --git a/runtime/openjdkjvmti/ti_phase.h b/runtime/openjdkjvmti/ti_phase.h
index bd15fa6..851fc27 100644
--- a/runtime/openjdkjvmti/ti_phase.h
+++ b/runtime/openjdkjvmti/ti_phase.h
@@ -57,6 +57,8 @@
struct PhaseCallback;
+ static jvmtiPhase GetPhaseUnchecked();
+
private:
static jvmtiPhase current_phase_;
};
diff --git a/runtime/openjdkjvmti/ti_search.cc b/runtime/openjdkjvmti/ti_search.cc
index 913d2b6..df80f85 100644
--- a/runtime/openjdkjvmti/ti_search.cc
+++ b/runtime/openjdkjvmti/ti_search.cc
@@ -34,15 +34,177 @@
#include "jni.h"
#include "art_jvmti.h"
+#include "base/enums.h"
#include "base/macros.h"
#include "class_linker.h"
#include "dex_file.h"
+#include "jni_internal.h"
+#include "mirror/class-inl.h"
+#include "mirror/object.h"
+#include "mirror/string.h"
+#include "obj_ptr-inl.h"
#include "runtime.h"
+#include "runtime_callbacks.h"
#include "scoped_thread_state_change-inl.h"
#include "ScopedLocalRef.h"
+#include "ti_phase.h"
+#include "thread-inl.h"
+#include "thread_list.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->FindDeclaredVirtualMethod(
+ "getProperty",
+ "(Ljava/lang/String;)Ljava/lang/String;",
+ art::kRuntimePointerSize);
+ DCHECK(get_property != nullptr);
+ art::ArtMethod* set_property =
+ properties_class->FindDeclaredVirtualMethod(
+ "setProperty",
+ "(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/Object;",
+ art::kRuntimePointerSize);
+ DCHECK(set_property != nullptr);
+
+ // 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 ATTRIBUTE_UNUSED,
const char* segment) {
art::Runtime* current = art::Runtime::Current();
@@ -78,14 +240,21 @@
return ERR(NULL_POINTER);
}
- art::Runtime* current = art::Runtime::Current();
- if (current == nullptr) {
+ 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 = current->GetSystemClassLoader();
+
+ jobject sys_class_loader = art::Runtime::Current()->GetSystemClassLoader();
if (sys_class_loader == nullptr) {
- // TODO: Support classpath change in OnLoad.
- return ERR(WRONG_PHASE);
+ // This is unexpected.
+ return ERR(INTERNAL);
}
// We'll use BaseDexClassLoader.addDexPath, as it takes care of array resizing etc. As a downside,
diff --git a/runtime/openjdkjvmti/ti_search.h b/runtime/openjdkjvmti/ti_search.h
index 6a52e80..cd7b4be 100644
--- a/runtime/openjdkjvmti/ti_search.h
+++ b/runtime/openjdkjvmti/ti_search.h
@@ -32,12 +32,17 @@
#ifndef ART_RUNTIME_OPENJDKJVMTI_TI_SEARCH_H_
#define ART_RUNTIME_OPENJDKJVMTI_TI_SEARCH_H_
+#include <vector>
+
#include "jvmti.h"
namespace openjdkjvmti {
class SearchUtil {
public:
+ static void Register();
+ static void Unregister();
+
static jvmtiError AddToBootstrapClassLoaderSearch(jvmtiEnv* env, const char* segment);
static jvmtiError AddToSystemClassLoaderSearch(jvmtiEnv* env, const char* segment);
diff --git a/test/936-search-onload/build b/test/936-search-onload/build
new file mode 100755
index 0000000..898e2e5
--- /dev/null
+++ b/test/936-search-onload/build
@@ -0,0 +1,17 @@
+#!/bin/bash
+#
+# Copyright 2016 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+./default-build "$@" --experimental agents
diff --git a/test/936-search-onload/expected.txt b/test/936-search-onload/expected.txt
new file mode 100644
index 0000000..2eec8e1
--- /dev/null
+++ b/test/936-search-onload/expected.txt
@@ -0,0 +1,3 @@
+B was loaded with boot classloader
+A was loaded with system classloader
+Done
diff --git a/test/936-search-onload/info.txt b/test/936-search-onload/info.txt
new file mode 100644
index 0000000..875a5f6
--- /dev/null
+++ b/test/936-search-onload/info.txt
@@ -0,0 +1 @@
+Tests basic functions in the jvmti plugin.
diff --git a/test/936-search-onload/run b/test/936-search-onload/run
new file mode 100755
index 0000000..67923a7
--- /dev/null
+++ b/test/936-search-onload/run
@@ -0,0 +1,21 @@
+#!/bin/bash
+#
+# Copyright 2016 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# This test checks whether dex files can be injected into parent classloaders. App images preload
+# classes, which will make the injection moot. Turn off app images to avoid the issue.
+
+./default-run "$@" --jvmti \
+ --no-app-image
diff --git a/test/936-search-onload/search_onload.cc b/test/936-search-onload/search_onload.cc
new file mode 100644
index 0000000..2286a46
--- /dev/null
+++ b/test/936-search-onload/search_onload.cc
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "search_onload.h"
+
+#include <inttypes.h>
+
+#include "android-base/stringprintf.h"
+#include "base/logging.h"
+#include "base/macros.h"
+#include "jni.h"
+#include "openjdkjvmti/jvmti.h"
+#include "ScopedUtfChars.h"
+
+#include "ti-agent/common_helper.h"
+#include "ti-agent/common_load.h"
+
+namespace art {
+namespace Test936SearchOnload {
+
+jint OnLoad(JavaVM* vm,
+ char* options ATTRIBUTE_UNUSED,
+ void* reserved ATTRIBUTE_UNUSED) {
+ if (vm->GetEnv(reinterpret_cast<void**>(&jvmti_env), JVMTI_VERSION_1_0)) {
+ printf("Unable to get jvmti env!\n");
+ return 1;
+ }
+ SetAllCapabilities(jvmti_env);
+
+ char* dex_loc = getenv("DEX_LOCATION");
+ std::string dex1 = android::base::StringPrintf("%s/936-search-onload.jar", dex_loc);
+ std::string dex2 = android::base::StringPrintf("%s/936-search-onload-ex.jar", dex_loc);
+
+ jvmtiError result = jvmti_env->AddToBootstrapClassLoaderSearch(dex1.c_str());
+ if (result != JVMTI_ERROR_NONE) {
+ printf("Could not add to bootstrap classloader.\n");
+ return 1;
+ }
+
+ result = jvmti_env->AddToSystemClassLoaderSearch(dex2.c_str());
+ if (result != JVMTI_ERROR_NONE) {
+ printf("Could not add to system classloader.\n");
+ return 1;
+ }
+
+ return JNI_OK;
+}
+
+} // namespace Test936SearchOnload
+} // namespace art
diff --git a/test/936-search-onload/search_onload.h b/test/936-search-onload/search_onload.h
new file mode 100644
index 0000000..e556892
--- /dev/null
+++ b/test/936-search-onload/search_onload.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ART_TEST_936_SEARCH_ONLOAD_SEARCH_ONLOAD_H_
+#define ART_TEST_936_SEARCH_ONLOAD_SEARCH_ONLOAD_H_
+
+#include <jni.h>
+
+namespace art {
+namespace Test936SearchOnload {
+
+jint OnLoad(JavaVM* vm, char* options, void* reserved);
+
+} // namespace Test936SearchOnload
+} // namespace art
+
+#endif // ART_TEST_936_SEARCH_ONLOAD_SEARCH_ONLOAD_H_
diff --git a/test/936-search-onload/src-ex/A.java b/test/936-search-onload/src-ex/A.java
new file mode 100644
index 0000000..64acb2f
--- /dev/null
+++ b/test/936-search-onload/src-ex/A.java
@@ -0,0 +1,18 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+public class A {
+}
\ No newline at end of file
diff --git a/test/936-search-onload/src/B.java b/test/936-search-onload/src/B.java
new file mode 100644
index 0000000..f1458c3
--- /dev/null
+++ b/test/936-search-onload/src/B.java
@@ -0,0 +1,18 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+public class B {
+}
\ No newline at end of file
diff --git a/test/936-search-onload/src/Main.java b/test/936-search-onload/src/Main.java
new file mode 100644
index 0000000..2e7a871
--- /dev/null
+++ b/test/936-search-onload/src/Main.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.util.Arrays;
+
+public class Main {
+ public static void main(String[] args) throws Exception {
+ doTest();
+ }
+
+ private static void doTest() throws Exception {
+ doTest(true, "B");
+ doTest(false, "A");
+ System.out.println("Done");
+ }
+
+ private static void doTest(boolean boot, String className) throws Exception {
+ ClassLoader expectedClassLoader;
+ if (boot) {
+ expectedClassLoader = Object.class.getClassLoader();
+ } else {
+ expectedClassLoader = ClassLoader.getSystemClassLoader();
+ }
+
+ Class<?> c = Class.forName(className, false, ClassLoader.getSystemClassLoader());
+ if (c.getClassLoader() != expectedClassLoader) {
+ throw new RuntimeException(className + "(" + boot + "): " +
+ c.getClassLoader() + " vs " + expectedClassLoader);
+ } else {
+ System.out.println(className + " was loaded with " + (boot ? "boot" : "system") +
+ " classloader");
+ }
+ }
+}
diff --git a/test/Android.bp b/test/Android.bp
index 287df13..1070645 100644
--- a/test/Android.bp
+++ b/test/Android.bp
@@ -272,6 +272,7 @@
"929-search/search.cc",
"931-agent-thread/agent_thread.cc",
"933-misc-events/misc_events.cc",
+ "936-search-onload/search_onload.cc",
],
shared_libs: [
"libbase",
diff --git a/test/ti-agent/common_load.cc b/test/ti-agent/common_load.cc
index c30c2b1..621d45a 100644
--- a/test/ti-agent/common_load.cc
+++ b/test/ti-agent/common_load.cc
@@ -28,6 +28,7 @@
#include "901-hello-ti-agent/basics.h"
#include "909-attach-agent/attach.h"
+#include "936-search-onload/search_onload.h"
namespace art {
@@ -112,6 +113,7 @@
{ "932-transform-saves", common_retransform::OnLoad, nullptr },
{ "934-load-transform", common_retransform::OnLoad, nullptr },
{ "935-non-retransformable", common_transform::OnLoad, nullptr },
+ { "936-search-onload", Test936SearchOnload::OnLoad, nullptr },
{ "937-hello-retransform-package", common_retransform::OnLoad, nullptr },
};