test/ti-stress/stress.cc

/*
 * Copyright 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 <jni.h>
#include <stdio.h>
#include <iostream>
#include <fstream>
#include <memory>
#include <stdio.h>
#include <sstream>
#include <strstream>

#include "jvmti.h"
#include "exec_utils.h"
#include "utils.h"

namespace art {

// Should we do a 'full_rewrite' with this test?
static constexpr bool kDoFullRewrite = true;

struct StressData {
  std::string dexter_cmd;
  std::string out_temp_dex;
  std::string in_temp_dex;
  bool vm_class_loader_initialized;
  bool trace_stress;
  bool redefine_stress;
};

static void WriteToFile(const std::string& fname, jint data_len, const unsigned char* data) {
  std::ofstream file(fname, std::ios::binary | std::ios::out | std::ios::trunc);
  file.write(reinterpret_cast<const char*>(data), data_len);
  file.flush();
}

static bool ReadIntoBuffer(const std::string& fname, /*out*/std::vector<unsigned char>* data) {
  std::ifstream file(fname, std::ios::binary | std::ios::in);
  file.seekg(0, std::ios::end);
  size_t len = file.tellg();
  data->resize(len);
  file.seekg(0);
  file.read(reinterpret_cast<char*>(data->data()), len);
  return len != 0;
}

// TODO rewrite later.
static bool DoExtractClassFromData(StressData* data,
                                   const std::string& class_name,
                                   jint in_len,
                                   const unsigned char* in_data,
                                   /*out*/std::vector<unsigned char>* dex) {
  // Write the dex file into a temporary file.
  WriteToFile(data->in_temp_dex, in_len, in_data);
  // Clear out file so even if something suppresses the exit value we will still detect dexter
  // failure.
  WriteToFile(data->out_temp_dex, 0, nullptr);
  // Have dexter do the extraction.
  std::vector<std::string> args;
  args.push_back(data->dexter_cmd);
  if (kDoFullRewrite) {
    args.push_back("-x");
    args.push_back("full_rewrite");
  }
  args.push_back("-e");
  args.push_back(class_name);
  args.push_back("-o");
  args.push_back(data->out_temp_dex);
  args.push_back(data->in_temp_dex);
  std::string error;
  if (ExecAndReturnCode(args, &error) != 0) {
    LOG(ERROR) << "unable to execute dexter: " << error;
    return false;
  }
  return ReadIntoBuffer(data->out_temp_dex, dex);
}

class ScopedThreadInfo {
 public:
  ScopedThreadInfo(jvmtiEnv* jvmtienv, JNIEnv* env, jthread thread)
      : jvmtienv_(jvmtienv), env_(env), free_name_(false) {
    memset(&info_, 0, sizeof(info_));
    if (thread == nullptr) {
      info_.name = const_cast<char*>("<NULLPTR>");
    } else if (jvmtienv->GetThreadInfo(thread, &info_) != JVMTI_ERROR_NONE) {
      info_.name = const_cast<char*>("<UNKNOWN THREAD>");
    } else {
      free_name_ = true;
    }
  }

  ~ScopedThreadInfo() {
    if (free_name_) {
      jvmtienv_->Deallocate(reinterpret_cast<unsigned char*>(info_.name));
    }
    env_->DeleteLocalRef(info_.thread_group);
    env_->DeleteLocalRef(info_.context_class_loader);
  }

  const char* GetName() const {
    return info_.name;
  }

 private:
  jvmtiEnv* jvmtienv_;
  JNIEnv* env_;
  bool free_name_;
  jvmtiThreadInfo info_;
};

class ScopedClassInfo {
 public:
  ScopedClassInfo(jvmtiEnv* jvmtienv, jclass c)
      : jvmtienv_(jvmtienv),
        class_(c),
        name_(nullptr),
        generic_(nullptr) {}

  ~ScopedClassInfo() {
    jvmtienv_->Deallocate(reinterpret_cast<unsigned char*>(name_));
    jvmtienv_->Deallocate(reinterpret_cast<unsigned char*>(generic_));
  }

  bool Init() {
    return jvmtienv_->GetClassSignature(class_, &name_, &generic_) == JVMTI_ERROR_NONE;
  }

  jclass GetClass() const {
    return class_;
  }
  const char* GetName() const {
    return name_;
  }
  const char* GetGeneric() const {
    return generic_;
  }

 private:
  jvmtiEnv* jvmtienv_;
  jclass class_;
  char* name_;
  char* generic_;
};

class ScopedMethodInfo {
 public:
  ScopedMethodInfo(jvmtiEnv* jvmtienv, JNIEnv* env, jmethodID m)
      : jvmtienv_(jvmtienv),
        env_(env),
        method_(m),
        declaring_class_(nullptr),
        class_info_(nullptr),
        name_(nullptr),
        signature_(nullptr),
        generic_(nullptr) {}

  ~ScopedMethodInfo() {
    env_->DeleteLocalRef(declaring_class_);
    jvmtienv_->Deallocate(reinterpret_cast<unsigned char*>(name_));
    jvmtienv_->Deallocate(reinterpret_cast<unsigned char*>(signature_));
    jvmtienv_->Deallocate(reinterpret_cast<unsigned char*>(generic_));
  }

  bool Init() {
    if (jvmtienv_->GetMethodDeclaringClass(method_, &declaring_class_) != JVMTI_ERROR_NONE) {
      return false;
    }
    class_info_.reset(new ScopedClassInfo(jvmtienv_, declaring_class_));
    return class_info_->Init() &&
        (jvmtienv_->GetMethodName(method_, &name_, &signature_, &generic_) == JVMTI_ERROR_NONE);
  }

  const ScopedClassInfo& GetDeclaringClassInfo() const {
    return *class_info_;
  }

  jclass GetDeclaringClass() const {
    return declaring_class_;
  }

  const char* GetName() const {
    return name_;
  }

  const char* GetSignature() const {
    return signature_;
  }

  const char* GetGeneric() const {
    return generic_;
  }

 private:
  jvmtiEnv* jvmtienv_;
  JNIEnv* env_;
  jmethodID method_;
  jclass declaring_class_;
  std::unique_ptr<ScopedClassInfo> class_info_;
  char* name_;
  char* signature_;
  char* generic_;

  friend std::ostream& operator<<(std::ostream &os, ScopedMethodInfo const& m);
};

std::ostream& operator<<(std::ostream &os, const ScopedMethodInfo* m) {
  return os << *m;
}

std::ostream& operator<<(std::ostream &os, ScopedMethodInfo const& m) {
  return os << m.GetDeclaringClassInfo().GetName() << "->" << m.GetName() << m.GetSignature();
}

static void doJvmtiMethodBind(jvmtiEnv* jvmtienv,
                              JNIEnv* env,
                              jthread thread,
                              jmethodID m,
                              void* address,
                              /*out*/void** out_address) {
  *out_address = address;
  ScopedThreadInfo thread_info(jvmtienv, env, thread);
  ScopedMethodInfo method_info(jvmtienv, env, m);
  if (!method_info.Init()) {
    LOG(ERROR) << "Unable to get method info!";
    return;
  }
  LOG(INFO) << "Loading native method \"" << method_info << "\". Thread is "
            << thread_info.GetName();
}

static std::string GetName(jvmtiEnv* jvmtienv, JNIEnv* jnienv, jobject obj) {
  jclass klass = jnienv->GetObjectClass(obj);
  char *cname, *cgen;
  if (jvmtienv->GetClassSignature(klass, &cname, &cgen) != JVMTI_ERROR_NONE) {
    LOG(ERROR) << "Unable to get class name!";
    jnienv->DeleteLocalRef(klass);
    return "<UNKNOWN>";
  }
  std::string name(cname);
  if (name == "Ljava/lang/String;") {
    jstring str = reinterpret_cast<jstring>(obj);
    const char* val = jnienv->GetStringUTFChars(str, nullptr);
    if (val == nullptr) {
      name += " (unable to get value)";
    } else {
      std::ostringstream oss;
      oss << name << " (value: \"" << val << "\")";
      name = oss.str();
      jnienv->ReleaseStringUTFChars(str, val);
    }
  }
  jvmtienv->Deallocate(reinterpret_cast<unsigned char*>(cname));
  jvmtienv->Deallocate(reinterpret_cast<unsigned char*>(cgen));
  jnienv->DeleteLocalRef(klass);
  return name;
}

static std::string GetValOf(jvmtiEnv* env, JNIEnv* jnienv, std::string type, jvalue val) {
  std::ostringstream oss;
  switch (type[0]) {
    case '[':
    case 'L':
      return val.l != nullptr ? GetName(env, jnienv, val.l) : "null";
    case 'Z':
      return val.z == JNI_TRUE ? "true" : "false";
    case 'B':
      oss << val.b;
      return oss.str();
    case 'C':
      oss << val.c;
      return oss.str();
    case 'S':
      oss << val.s;
      return oss.str();
    case 'I':
      oss << val.i;
      return oss.str();
    case 'J':
      oss << val.j;
      return oss.str();
    case 'F':
      oss << val.f;
      return oss.str();
    case 'D':
      oss << val.d;
      return oss.str();
    case 'V':
      return "<void>";
    default:
      return "<ERROR Found type " + type + ">";
  }
}

void JNICALL MethodExitHook(jvmtiEnv* jvmtienv,
                            JNIEnv* env,
                            jthread thread,
                            jmethodID m,
                            jboolean was_popped_by_exception,
                            jvalue val) {
  ScopedThreadInfo info(jvmtienv, env, thread);
  ScopedMethodInfo method_info(jvmtienv, env, m);
  if (!method_info.Init()) {
    LOG(ERROR) << "Unable to get method info!";
    return;
  }
  std::string type(method_info.GetSignature());
  type = type.substr(type.find(")") + 1);
  std::string out_val(was_popped_by_exception ? "" : GetValOf(jvmtienv, env, type, val));
  LOG(INFO) << "Leaving method \"" << method_info << "\". Thread is \"" << info.GetName() << "\"."
            << std::endl
            << "    Cause: " << (was_popped_by_exception ? "exception" : "return ")
            << out_val << ".";
}

void JNICALL MethodEntryHook(jvmtiEnv* jvmtienv,
                             JNIEnv* env,
                             jthread thread,
                             jmethodID m) {
  ScopedThreadInfo info(jvmtienv, env, thread);
  ScopedMethodInfo method_info(jvmtienv, env, m);
  if (!method_info.Init()) {
    LOG(ERROR) << "Unable to get method info!";
    return;
  }
  LOG(INFO) << "Entering method \"" << method_info << "\". Thread is \"" << info.GetName() << "\"";
}

// The hook we are using.
void JNICALL ClassFileLoadHookSecretNoOp(jvmtiEnv* jvmti,
                                         JNIEnv* jni_env ATTRIBUTE_UNUSED,
                                         jclass class_being_redefined ATTRIBUTE_UNUSED,
                                         jobject loader ATTRIBUTE_UNUSED,
                                         const char* name,
                                         jobject protection_domain ATTRIBUTE_UNUSED,
                                         jint class_data_len,
                                         const unsigned char* class_data,
                                         jint* new_class_data_len,
                                         unsigned char** new_class_data) {
  std::vector<unsigned char> out;
  std::string name_str(name);
  // Make the jvmti semi-descriptor into the java style descriptor (though with $ for inner
  // classes).
  std::replace(name_str.begin(), name_str.end(), '/', '.');
  StressData* data = nullptr;
  CHECK_EQ(jvmti->GetEnvironmentLocalStorage(reinterpret_cast<void**>(&data)),
           JVMTI_ERROR_NONE);
  if (!data->vm_class_loader_initialized) {
    LOG(WARNING) << "Ignoring load of class " << name << " because VMClassLoader is not yet "
                 << "initialized. Transforming this class could cause spurious test failures.";
    return;
  } else if (DoExtractClassFromData(data, name_str, class_data_len, class_data, /*out*/ &out)) {
    LOG(INFO) << "Extracted class: " << name;
    unsigned char* new_data;
    CHECK_EQ(JVMTI_ERROR_NONE, jvmti->Allocate(out.size(), &new_data));
    memcpy(new_data, out.data(), out.size());
    *new_class_data_len = static_cast<jint>(out.size());
    *new_class_data = new_data;
  } else {
    std::cerr << "Unable to extract class " << name_str << std::endl;
    *new_class_data_len = 0;
    *new_class_data = nullptr;
  }
}

static std::string AdvanceOption(const std::string& ops) {
  return ops.substr(ops.find(',') + 1);
}

static bool HasNextOption(const std::string& ops) {
  return ops.find(',') != std::string::npos;
}

static std::string GetOption(const std::string& in) {
  return in.substr(0, in.find(','));
}

// Options are
// jvmti-stress,[redefine,${DEXTER_BINARY},${TEMP_FILE_1},${TEMP_FILE_2},][trace]
static void ReadOptions(StressData* data, char* options) {
  std::string ops(options);
  CHECK_EQ(GetOption(ops), "jvmti-stress") << "Options should start with jvmti-stress";
  do {
    ops = AdvanceOption(ops);
    std::string cur = GetOption(ops);
    if (cur == "trace") {
      data->trace_stress = true;
    } else if (cur == "redefine") {
      data->redefine_stress = true;
      ops = AdvanceOption(ops);
      data->dexter_cmd = GetOption(ops);
      ops = AdvanceOption(ops);
      data->in_temp_dex = GetOption(ops);
      ops = AdvanceOption(ops);
      data->out_temp_dex = GetOption(ops);
    } else {
      LOG(FATAL) << "Unknown option: " << GetOption(ops);
    }
  } while (HasNextOption(ops));
}

// Do final setup during the VMInit callback. By this time most things are all setup.
static void JNICALL PerformFinalSetupVMInit(jvmtiEnv *jvmti_env,
                                            JNIEnv* jni_env,
                                            jthread thread ATTRIBUTE_UNUSED) {
  // Load the VMClassLoader class. We will get a ClassNotFound exception because we don't have
  // visibility but the class will be loaded behind the scenes.
  LOG(INFO) << "manual load & initialization of class java/lang/VMClassLoader!";
  jclass klass = jni_env->FindClass("java/lang/VMClassLoader");
  StressData* data = nullptr;
  CHECK_EQ(jvmti_env->GetEnvironmentLocalStorage(reinterpret_cast<void**>(&data)),
           JVMTI_ERROR_NONE);
  // We need to make sure that VMClassLoader is initialized before we start redefining anything
  // since it can give (non-fatal) error messages if it's initialized after we've redefined BCP
  // classes. These error messages are expected and no problem but they will mess up our testing
  // infrastructure.
  if (klass == nullptr) {
    // Probably on RI. Clear the exception so we can continue but don't mark vmclassloader as
    // initialized.
    LOG(WARNING) << "Unable to find VMClassLoader class!";
    jni_env->ExceptionClear();
  } else {
    // GetMethodID is spec'd to cause the class to be initialized.
    jni_env->GetMethodID(klass, "hashCode", "()I");
    jni_env->DeleteLocalRef(klass);
    data->vm_class_loader_initialized = true;
  }
  if (data->trace_stress) {
    if (jvmti_env->SetEventNotificationMode(JVMTI_ENABLE,
                                            JVMTI_EVENT_METHOD_ENTRY,
                                            nullptr) != JVMTI_ERROR_NONE) {
      LOG(ERROR) << "Unable to enable JVMTI_EVENT_METHOD_ENTRY event!";
    }
    if (jvmti_env->SetEventNotificationMode(JVMTI_ENABLE,
                                        JVMTI_EVENT_METHOD_EXIT,
                                        nullptr) != JVMTI_ERROR_NONE) {
      LOG(ERROR) << "Unable to enable JVMTI_EVENT_METHOD_EXIT event!";
    }
  }
}

extern "C" JNIEXPORT jint JNICALL Agent_OnLoad(JavaVM* vm,
                                               char* options,
                                               void* reserved ATTRIBUTE_UNUSED) {
  jvmtiEnv* jvmti = nullptr;
  if (vm->GetEnv(reinterpret_cast<void**>(&jvmti), JVMTI_VERSION_1_0)) {
    LOG(ERROR) << "Unable to get jvmti env.";
    return 1;
  }
  StressData* data = nullptr;
  if (JVMTI_ERROR_NONE != jvmti->Allocate(sizeof(StressData),
                                          reinterpret_cast<unsigned char**>(&data))) {
    LOG(ERROR) << "Unable to allocate data for stress test.";
    return 1;
  }
  memset(data, 0, sizeof(StressData));
  // Read the options into the static variables that hold them.
  ReadOptions(data, options);
  // Save the data
  if (JVMTI_ERROR_NONE != jvmti->SetEnvironmentLocalStorage(data)) {
    LOG(ERROR) << "Unable to save stress test data.";
    return 1;
  }

  // Just get all capabilities.
  jvmtiCapabilities caps;
  jvmti->GetPotentialCapabilities(&caps);
  jvmti->AddCapabilities(&caps);

  // Set callbacks.
  jvmtiEventCallbacks cb;
  memset(&cb, 0, sizeof(cb));
  cb.ClassFileLoadHook = ClassFileLoadHookSecretNoOp;
  cb.NativeMethodBind = doJvmtiMethodBind;
  cb.VMInit = PerformFinalSetupVMInit;
  cb.MethodEntry = MethodEntryHook;
  cb.MethodExit = MethodExitHook;
  if (jvmti->SetEventCallbacks(&cb, sizeof(cb)) != JVMTI_ERROR_NONE) {
    LOG(ERROR) << "Unable to set class file load hook cb!";
    return 1;
  }
  if (jvmti->SetEventNotificationMode(JVMTI_ENABLE,
                                      JVMTI_EVENT_NATIVE_METHOD_BIND,
                                      nullptr) != JVMTI_ERROR_NONE) {
    LOG(ERROR) << "Unable to enable JVMTI_EVENT_NATIVE_METHOD_BIND event!";
    return 1;
  }
  if (jvmti->SetEventNotificationMode(JVMTI_ENABLE,
                                      JVMTI_EVENT_VM_INIT,
                                      nullptr) != JVMTI_ERROR_NONE) {
    LOG(ERROR) << "Unable to enable JVMTI_EVENT_VM_INIT event!";
    return 1;
  }
  if (data->redefine_stress) {
    if (jvmti->SetEventNotificationMode(JVMTI_ENABLE,
                                        JVMTI_EVENT_CLASS_FILE_LOAD_HOOK,
                                        nullptr) != JVMTI_ERROR_NONE) {
      LOG(ERROR) << "Unable to enable CLASS_FILE_LOAD_HOOK event!";
      return 1;
    }
  }
  return 0;
}

}  // namespace art