/*
* Copyright (C) 2006 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.
*/
#define LOG_TAG "JavaBinder"
//#define LOG_NDEBUG 0
#include "android_os_Parcel.h"
#include "android_util_Binder.h"
#include "JNIHelp.h"
#include <fcntl.h>
#include <inttypes.h>
#include <stdio.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <android-base/stringprintf.h>
#include <binder/IInterface.h>
#include <binder/IServiceManager.h>
#include <binder/IPCThreadState.h>
#include <binder/Parcel.h>
#include <binder/ProcessState.h>
#include <log/log.h>
#include <utils/Atomic.h>
#include <utils/KeyedVector.h>
#include <utils/List.h>
#include <utils/Log.h>
#include <utils/String8.h>
#include <utils/SystemClock.h>
#include <utils/threads.h>
#include <ScopedUtfChars.h>
#include <ScopedLocalRef.h>
#include "core_jni_helpers.h"
//#undef ALOGV
//#define ALOGV(...) fprintf(stderr, __VA_ARGS__)
#define DEBUG_DEATH 0
#if DEBUG_DEATH
#define LOGDEATH ALOGD
#else
#define LOGDEATH ALOGV
#endif
using namespace android;
// ----------------------------------------------------------------------------
static struct bindernative_offsets_t
{
// Class state.
jclass mClass;
jmethodID mExecTransact;
// Object state.
jfieldID mObject;
} gBinderOffsets;
// ----------------------------------------------------------------------------
static struct binderinternal_offsets_t
{
// Class state.
jclass mClass;
jmethodID mForceGc;
} gBinderInternalOffsets;
// ----------------------------------------------------------------------------
static struct error_offsets_t
{
jclass mClass;
} gErrorOffsets;
// ----------------------------------------------------------------------------
static struct binderproxy_offsets_t
{
// Class state.
jclass mClass;
jmethodID mConstructor;
jmethodID mSendDeathNotice;
// Object state.
jfieldID mObject;
jfieldID mSelf;
jfieldID mOrgue;
} gBinderProxyOffsets;
static struct class_offsets_t
{
jmethodID mGetName;
} gClassOffsets;
// ----------------------------------------------------------------------------
static struct log_offsets_t
{
// Class state.
jclass mClass;
jmethodID mLogE;
} gLogOffsets;
static struct parcel_file_descriptor_offsets_t
{
jclass mClass;
jmethodID mConstructor;
} gParcelFileDescriptorOffsets;
static struct strict_mode_callback_offsets_t
{
jclass mClass;
jmethodID mCallback;
} gStrictModeCallbackOffsets;
// ****************************************************************************
// ****************************************************************************
// ****************************************************************************
static volatile int32_t gNumRefsCreated = 0;
static volatile int32_t gNumProxyRefs = 0;
static volatile int32_t gNumLocalRefs = 0;
static volatile int32_t gNumDeathRefs = 0;
static void incRefsCreated(JNIEnv* env)
{
int old = android_atomic_inc(&gNumRefsCreated);
if (old == 200) {
android_atomic_and(0, &gNumRefsCreated);
env->CallStaticVoidMethod(gBinderInternalOffsets.mClass,
gBinderInternalOffsets.mForceGc);
} else {
ALOGV("Now have %d binder ops", old);
}
}
static JavaVM* jnienv_to_javavm(JNIEnv* env)
{
JavaVM* vm;
return env->GetJavaVM(&vm) >= 0 ? vm : NULL;
}
static JNIEnv* javavm_to_jnienv(JavaVM* vm)
{
JNIEnv* env;
return vm->GetEnv((void **)&env, JNI_VERSION_1_4) >= 0 ? env : NULL;
}
static void report_exception(JNIEnv* env, jthrowable excep, const char* msg)
{
env->ExceptionClear();
jstring tagstr = env->NewStringUTF(LOG_TAG);
jstring msgstr = NULL;
if (tagstr != NULL) {
msgstr = env->NewStringUTF(msg);
}
if ((tagstr == NULL) || (msgstr == NULL)) {
env->ExceptionClear(); /* assume exception (OOM?) was thrown */
ALOGE("Unable to call Log.e()\n");
ALOGE("%s", msg);
goto bail;
}
env->CallStaticIntMethod(
gLogOffsets.mClass, gLogOffsets.mLogE, tagstr, msgstr, excep);
if (env->ExceptionCheck()) {
/* attempting to log the failure has failed */
ALOGW("Failed trying to log exception, msg='%s'\n", msg);
env->ExceptionClear();
}
if (env->IsInstanceOf(excep, gErrorOffsets.mClass)) {
/*
* It's an Error: Reraise the exception and ask the runtime to abort.
*/
// Try to get the exception string. Sometimes logcat isn't available,
// so try to add it to the abort message.
std::string exc_msg = "(Unknown exception message)";
{
ScopedLocalRef<jclass> exc_class(env, env->GetObjectClass(excep));
jmethodID method_id = env->GetMethodID(exc_class.get(),
"toString",
"()Ljava/lang/String;");
ScopedLocalRef<jstring> jstr(
env,
reinterpret_cast<jstring>(
env->CallObjectMethod(excep, method_id)));
env->ExceptionClear(); // Just for good measure.
if (jstr.get() != nullptr) {
ScopedUtfChars jstr_utf(env, jstr.get());
exc_msg = jstr_utf.c_str();
}
}
env->Throw(excep);
ALOGE("java.lang.Error thrown during binder transaction (stack trace follows) : ");
env->ExceptionDescribe();
std::string error_msg = base::StringPrintf(
"java.lang.Error thrown during binder transaction: %s",
exc_msg.c_str());
env->FatalError(error_msg.c_str());
}
bail:
/* discard local refs created for us by VM */
env->DeleteLocalRef(tagstr);
env->DeleteLocalRef(msgstr);
}
class JavaBBinderHolder;
class JavaBBinder : public BBinder
{
public:
JavaBBinder(JNIEnv* env, jobject object)
: mVM(jnienv_to_javavm(env)), mObject(env->NewGlobalRef(object))
{
ALOGV("Creating JavaBBinder %p\n", this);
android_atomic_inc(&gNumLocalRefs);
incRefsCreated(env);
}
bool checkSubclass(const void* subclassID) const
{
return subclassID == &gBinderOffsets;
}
jobject object() const
{
return mObject;
}
protected:
virtual ~JavaBBinder()
{
ALOGV("Destroying JavaBBinder %p\n", this);
android_atomic_dec(&gNumLocalRefs);
JNIEnv* env = javavm_to_jnienv(mVM);
env->DeleteGlobalRef(mObject);
}
virtual status_t onTransact(
uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags = 0)
{
JNIEnv* env = javavm_to_jnienv(mVM);
ALOGV("onTransact() on %p calling object %p in env %p vm %p\n", this, mObject, env, mVM);
IPCThreadState* thread_state = IPCThreadState::self();
const int32_t strict_policy_before = thread_state->getStrictModePolicy();
//printf("Transact from %p to Java code sending: ", this);
//data.print();
//printf("\n");
jboolean res = env->CallBooleanMethod(mObject, gBinderOffsets.mExecTransact,
code, reinterpret_cast<jlong>(&data), reinterpret_cast<jlong>(reply), flags);
if (env->ExceptionCheck()) {
jthrowable excep = env->ExceptionOccurred();
report_exception(env, excep,
"*** Uncaught remote exception! "
"(Exceptions are not yet supported across processes.)");
res = JNI_FALSE;
/* clean up JNI local ref -- we don't return to Java code */
env->DeleteLocalRef(excep);
}
// Check if the strict mode state changed while processing the
// call. The Binder state will be restored by the underlying
// Binder system in IPCThreadState, however we need to take care
// of the parallel Java state as well.
if (thread_state->getStrictModePolicy() != strict_policy_before) {
set_dalvik_blockguard_policy(env, strict_policy_before);
}
if (env->ExceptionCheck()) {
jthrowable excep = env->ExceptionOccurred();
report_exception(env, excep,
"*** Uncaught exception in onBinderStrictModePolicyChange");
/* clean up JNI local ref -- we don't return to Java code */
env->DeleteLocalRef(excep);
}
// Need to always call through the native implementation of
// SYSPROPS_TRANSACTION.
if (code == SYSPROPS_TRANSACTION) {
BBinder::onTransact(code, data, reply, flags);
}
//aout << "onTransact to Java code; result=" << res << endl
// << "Transact from " << this << " to Java code returning "
// << reply << ": " << *reply << endl;
return res != JNI_FALSE ? NO_ERROR : UNKNOWN_TRANSACTION;
}
virtual status_t dump(int fd, const Vector<String16>& args)
{
return 0;
}
private:
JavaVM* const mVM;
jobject const mObject;
};
// ----------------------------------------------------------------------------
class JavaBBinderHolder : public RefBase
{
public:
sp<JavaBBinder> get(JNIEnv* env, jobject obj)
{
AutoMutex _l(mLock);
sp<JavaBBinder> b = mBinder.promote();
if (b == NULL) {
b = new JavaBBinder(env, obj);
mBinder = b;
ALOGV("Creating JavaBinder %p (refs %p) for Object %p, weakCount=%" PRId32 "\n",
b.get(), b->getWeakRefs(), obj, b->getWeakRefs()->getWeakCount());
}
return b;
}
sp<JavaBBinder> getExisting()
{
AutoMutex _l(mLock);
return mBinder.promote();
}
private:
Mutex mLock;
wp<JavaBBinder> mBinder;
};
// ----------------------------------------------------------------------------
// Per-IBinder death recipient bookkeeping. This is how we reconcile local jobject
// death recipient references passed in through JNI with the permanent corresponding
// JavaDeathRecipient objects.
class JavaDeathRecipient;
class DeathRecipientList : public RefBase {
List< sp<JavaDeathRecipient> > mList;
Mutex mLock;
public:
DeathRecipientList();
~DeathRecipientList();
void add(const sp<JavaDeathRecipient>& recipient);
void remove(const sp<JavaDeathRecipient>& recipient);
sp<JavaDeathRecipient> find(jobject recipient);
Mutex& lock(); // Use with care; specifically for mutual exclusion during binder death
};
// ----------------------------------------------------------------------------
class JavaDeathRecipient : public IBinder::DeathRecipient
{
public:
JavaDeathRecipient(JNIEnv* env, jobject object, const sp<DeathRecipientList>& list)
: mVM(jnienv_to_javavm(env)), mObject(env->NewGlobalRef(object)),
mObjectWeak(NULL), mList(list)
{
// These objects manage their own lifetimes so are responsible for final bookkeeping.
// The list holds a strong reference to this object.
LOGDEATH("Adding JDR %p to DRL %p", this, list.get());
list->add(this);
android_atomic_inc(&gNumDeathRefs);
incRefsCreated(env);
}
void binderDied(const wp<IBinder>& who)
{
LOGDEATH("Receiving binderDied() on JavaDeathRecipient %p\n", this);
if (mObject != NULL) {
JNIEnv* env = javavm_to_jnienv(mVM);
env->CallStaticVoidMethod(gBinderProxyOffsets.mClass,
gBinderProxyOffsets.mSendDeathNotice, mObject);
if (env->ExceptionCheck()) {
jthrowable excep = env->ExceptionOccurred();
report_exception(env, excep,
"*** Uncaught exception returned from death notification!");
}
// Serialize with our containing DeathRecipientList so that we can't
// delete the global ref on mObject while the list is being iterated.
sp<DeathRecipientList> list = mList.promote();
if (list != NULL) {
AutoMutex _l(list->lock());
// Demote from strong ref to weak after binderDied() has been delivered,
// to allow the DeathRecipient and BinderProxy to be GC'd if no longer needed.
mObjectWeak = env->NewWeakGlobalRef(mObject);
env->DeleteGlobalRef(mObject);
mObject = NULL;
}
}
}
void clearReference()
{
sp<DeathRecipientList> list = mList.promote();
if (list != NULL) {
LOGDEATH("Removing JDR %p from DRL %p", this, list.get());
list->remove(this);
} else {
LOGDEATH("clearReference() on JDR %p but DRL wp purged", this);
}
}
bool matches(jobject obj) {
bool result;
JNIEnv* env = javavm_to_jnienv(mVM);
if (mObject != NULL) {
result = env->IsSameObject(obj, mObject);
} else {
jobject me = env->NewLocalRef(mObjectWeak);
result = env->IsSameObject(obj, me);
env->DeleteLocalRef(me);
}
return result;
}
void warnIfStillLive() {
if (mObject != NULL) {
// Okay, something is wrong -- we have a hard reference to a live death
// recipient on the VM side, but the list is being torn down.
JNIEnv* env = javavm_to_jnienv(mVM);
ScopedLocalRef<jclass> objClassRef(env, env->GetObjectClass(mObject));
ScopedLocalRef<jstring> nameRef(env,
(jstring) env->CallObjectMethod(objClassRef.get(), gClassOffsets.mGetName));
ScopedUtfChars nameUtf(env, nameRef.get());
if (nameUtf.c_str() != NULL) {
ALOGW("BinderProxy is being destroyed but the application did not call "
"unlinkToDeath to unlink all of its death recipients beforehand. "
"Releasing leaked death recipient: %s", nameUtf.c_str());
} else {
ALOGW("BinderProxy being destroyed; unable to get DR object name");
env->ExceptionClear();
}
}
}
protected:
virtual ~JavaDeathRecipient()
{
//ALOGI("Removing death ref: recipient=%p\n", mObject);
android_atomic_dec(&gNumDeathRefs);
JNIEnv* env = javavm_to_jnienv(mVM);
if (mObject != NULL) {
env->DeleteGlobalRef(mObject);
} else {
env->DeleteWeakGlobalRef(mObjectWeak);
}
}
private:
JavaVM* const mVM;
jobject mObject;
jweak mObjectWeak; // will be a weak ref to the same VM-side DeathRecipient after binderDied()
wp<DeathRecipientList> mList;
};
// ----------------------------------------------------------------------------
DeathRecipientList::DeathRecipientList() {
LOGDEATH("New DRL @ %p", this);
}
DeathRecipientList::~DeathRecipientList() {
LOGDEATH("Destroy DRL @ %p", this);
AutoMutex _l(mLock);
// Should never happen -- the JavaDeathRecipient objects that have added themselves
// to the list are holding references on the list object. Only when they are torn
// down can the list header be destroyed.
if (mList.size() > 0) {
List< sp<JavaDeathRecipient> >::iterator iter;
for (iter = mList.begin(); iter != mList.end(); iter++) {
(*iter)->warnIfStillLive();
}
}
}
void DeathRecipientList::add(const sp<JavaDeathRecipient>& recipient) {
AutoMutex _l(mLock);
LOGDEATH("DRL @ %p : add JDR %p", this, recipient.get());
mList.push_back(recipient);
}
void DeathRecipientList::remove(const sp<JavaDeathRecipient>& recipient) {
AutoMutex _l(mLock);
List< sp<JavaDeathRecipient> >::iterator iter;
for (iter = mList.begin(); iter != mList.end(); iter++) {
if (*iter == recipient) {
LOGDEATH("DRL @ %p : remove JDR %p", this, recipient.get());
mList.erase(iter);
return;
}
}
}
sp<JavaDeathRecipient> DeathRecipientList::find(jobject recipient) {
AutoMutex _l(mLock);
List< sp<JavaDeathRecipient> >::iterator iter;
for (iter = mList.begin(); iter != mList.end(); iter++) {
if ((*iter)->matches(recipient)) {
return *iter;
}
}
return NULL;
}
Mutex& DeathRecipientList::lock() {
return mLock;
}
// ----------------------------------------------------------------------------
namespace android {
static void proxy_cleanup(const void* id, void* obj, void* cleanupCookie)
{
android_atomic_dec(&gNumProxyRefs);
JNIEnv* env = javavm_to_jnienv((JavaVM*)cleanupCookie);
env->DeleteGlobalRef((jobject)obj);
}
static Mutex mProxyLock;
jobject javaObjectForIBinder(JNIEnv* env, const sp<IBinder>& val)
{
if (val == NULL) return NULL;
if (val->checkSubclass(&gBinderOffsets)) {
// One of our own!
jobject object = static_cast<JavaBBinder*>(val.get())->object();
LOGDEATH("objectForBinder %p: it's our own %p!\n", val.get(), object);
return object;
}
// For the rest of the function we will hold this lock, to serialize
// looking/creation/destruction of Java proxies for native Binder proxies.
AutoMutex _l(mProxyLock);
// Someone else's... do we know about it?
jobject object = (jobject)val->findObject(&gBinderProxyOffsets);
if (object != NULL) {
jobject res = jniGetReferent(env, object);
if (res != NULL) {
ALOGV("objectForBinder %p: found existing %p!\n", val.get(), res);
return res;
}
LOGDEATH("Proxy object %p of IBinder %p no longer in working set!!!", object, val.get());
android_atomic_dec(&gNumProxyRefs);
val->detachObject(&gBinderProxyOffsets);
env->DeleteGlobalRef(object);
}
object = env->NewObject(gBinderProxyOffsets.mClass, gBinderProxyOffsets.mConstructor);
if (object != NULL) {
LOGDEATH("objectForBinder %p: created new proxy %p !\n", val.get(), object);
// The proxy holds a reference to the native object.
env->SetLongField(object, gBinderProxyOffsets.mObject, (jlong)val.get());
val->incStrong((void*)javaObjectForIBinder);
// The native object needs to hold a weak reference back to the
// proxy, so we can retrieve the same proxy if it is still active.
jobject refObject = env->NewGlobalRef(
env->GetObjectField(object, gBinderProxyOffsets.mSelf));
val->attachObject(&gBinderProxyOffsets, refObject,
jnienv_to_javavm(env), proxy_cleanup);
// Also remember the death recipients registered on this proxy
sp<DeathRecipientList> drl = new DeathRecipientList;
drl->incStrong((void*)javaObjectForIBinder);
env->SetLongField(object, gBinderProxyOffsets.mOrgue, reinterpret_cast<jlong>(drl.get()));
// Note that a new object reference has been created.
android_atomic_inc(&gNumProxyRefs);
incRefsCreated(env);
}
return object;
}
sp<IBinder> ibinderForJavaObject(JNIEnv* env, jobject obj)
{
if (obj == NULL) return NULL;
if (env->IsInstanceOf(obj, gBinderOffsets.mClass)) {
JavaBBinderHolder* jbh = (JavaBBinderHolder*)
env->GetLongField(obj, gBinderOffsets.mObject);
return jbh != NULL ? jbh->get(env, obj) : NULL;
}
if (env->IsInstanceOf(obj, gBinderProxyOffsets.mClass)) {
return (IBinder*)
env->GetLongField(obj, gBinderProxyOffsets.mObject);
}
ALOGW("ibinderForJavaObject: %p is not a Binder object", obj);
return NULL;
}
jobject newParcelFileDescriptor(JNIEnv* env, jobject fileDesc)
{
return env->NewObject(
gParcelFileDescriptorOffsets.mClass, gParcelFileDescriptorOffsets.mConstructor, fileDesc);
}
void set_dalvik_blockguard_policy(JNIEnv* env, jint strict_policy)
{
// Call back into android.os.StrictMode#onBinderStrictModePolicyChange
// to sync our state back to it. See the comments in StrictMode.java.
env->CallStaticVoidMethod(gStrictModeCallbackOffsets.mClass,
gStrictModeCallbackOffsets.mCallback,
strict_policy);
}
void signalExceptionForError(JNIEnv* env, jobject obj, status_t err,
bool canThrowRemoteException, int parcelSize)
{
switch (err) {
case UNKNOWN_ERROR:
jniThrowException(env, "java/lang/RuntimeException", "Unknown error");
break;
case NO_MEMORY:
jniThrowException(env, "java/lang/OutOfMemoryError", NULL);
break;
case INVALID_OPERATION:
jniThrowException(env, "java/lang/UnsupportedOperationException", NULL);
break;
case BAD_VALUE:
jniThrowException(env, "java/lang/IllegalArgumentException", NULL);
break;
case BAD_INDEX:
jniThrowException(env, "java/lang/IndexOutOfBoundsException", NULL);
break;
case BAD_TYPE:
jniThrowException(env, "java/lang/IllegalArgumentException", NULL);
break;
case NAME_NOT_FOUND:
jniThrowException(env, "java/util/NoSuchElementException", NULL);
break;
case PERMISSION_DENIED:
jniThrowException(env, "java/lang/SecurityException", NULL);
break;
case NOT_ENOUGH_DATA:
jniThrowException(env, "android/os/ParcelFormatException", "Not enough data");
break;
case NO_INIT:
jniThrowException(env, "java/lang/RuntimeException", "Not initialized");
break;
case ALREADY_EXISTS:
jniThrowException(env, "java/lang/RuntimeException", "Item already exists");
break;
case DEAD_OBJECT:
// DeadObjectException is a checked exception, only throw from certain methods.
jniThrowException(env, canThrowRemoteException
? "android/os/DeadObjectException"
: "java/lang/RuntimeException", NULL);
break;
case UNKNOWN_TRANSACTION:
jniThrowException(env, "java/lang/RuntimeException", "Unknown transaction code");
break;
case FAILED_TRANSACTION: {
ALOGE("!!! FAILED BINDER TRANSACTION !!! (parcel size = %d)", parcelSize);
const char* exceptionToThrow;
char msg[128];
// TransactionTooLargeException is a checked exception, only throw from certain methods.
// FIXME: Transaction too large is the most common reason for FAILED_TRANSACTION
// but it is not the only one. The Binder driver can return BR_FAILED_REPLY
// for other reasons also, such as if the transaction is malformed or
// refers to an FD that has been closed. We should change the driver
// to enable us to distinguish these cases in the future.
if (canThrowRemoteException && parcelSize > 200*1024) {
// bona fide large payload
exceptionToThrow = "android/os/TransactionTooLargeException";
snprintf(msg, sizeof(msg)-1, "data parcel size %d bytes", parcelSize);
} else {
// Heuristic: a payload smaller than this threshold "shouldn't" be too
// big, so it's probably some other, more subtle problem. In practice
// it seems to always mean that the remote process died while the binder
// transaction was already in flight.
exceptionToThrow = (canThrowRemoteException)
? "android/os/DeadObjectException"
: "java/lang/RuntimeException";
snprintf(msg, sizeof(msg)-1,
"Transaction failed on small parcel; remote process probably died");
}
jniThrowException(env, exceptionToThrow, msg);
} break;
case FDS_NOT_ALLOWED:
jniThrowException(env, "java/lang/RuntimeException",
"Not allowed to write file descriptors here");
break;
case UNEXPECTED_NULL:
jniThrowNullPointerException(env, NULL);
break;
case -EBADF:
jniThrowException(env, "java/lang/RuntimeException",
"Bad file descriptor");
break;
case -ENFILE:
jniThrowException(env, "java/lang/RuntimeException",
"File table overflow");
break;
case -EMFILE:
jniThrowException(env, "java/lang/RuntimeException",
"Too many open files");
break;
case -EFBIG:
jniThrowException(env, "java/lang/RuntimeException",
"File too large");
break;
case -ENOSPC:
jniThrowException(env, "java/lang/RuntimeException",
"No space left on device");
break;
case -ESPIPE:
jniThrowException(env, "java/lang/RuntimeException",
"Illegal seek");
break;
case -EROFS:
jniThrowException(env, "java/lang/RuntimeException",
"Read-only file system");
break;
case -EMLINK:
jniThrowException(env, "java/lang/RuntimeException",
"Too many links");
break;
default:
ALOGE("Unknown binder error code. 0x%" PRIx32, err);
String8 msg;
msg.appendFormat("Unknown binder error code. 0x%" PRIx32, err);
// RemoteException is a checked exception, only throw from certain methods.
jniThrowException(env, canThrowRemoteException
? "android/os/RemoteException" : "java/lang/RuntimeException", msg.string());
break;
}
}
}
// ----------------------------------------------------------------------------
static jint android_os_Binder_getCallingPid(JNIEnv* env, jobject clazz)
{
return IPCThreadState::self()->getCallingPid();
}
static jint android_os_Binder_getCallingUid(JNIEnv* env, jobject clazz)
{
return IPCThreadState::self()->getCallingUid();
}
static jlong android_os_Binder_clearCallingIdentity(JNIEnv* env, jobject clazz)
{
return IPCThreadState::self()->clearCallingIdentity();
}
static void android_os_Binder_restoreCallingIdentity(JNIEnv* env, jobject clazz, jlong token)
{
// XXX temporary sanity check to debug crashes.
int uid = (int)(token>>32);
if (uid > 0 && uid < 999) {
// In Android currently there are no uids in this range.
char buf[128];
sprintf(buf, "Restoring bad calling ident: 0x%" PRIx64, token);
jniThrowException(env, "java/lang/IllegalStateException", buf);
return;
}
IPCThreadState::self()->restoreCallingIdentity(token);
}
static void android_os_Binder_setThreadStrictModePolicy(JNIEnv* env, jobject clazz, jint policyMask)
{
IPCThreadState::self()->setStrictModePolicy(policyMask);
}
static jint android_os_Binder_getThreadStrictModePolicy(JNIEnv* env, jobject clazz)
{
return IPCThreadState::self()->getStrictModePolicy();
}
static void android_os_Binder_flushPendingCommands(JNIEnv* env, jobject clazz)
{
IPCThreadState::self()->flushCommands();
}
static void android_os_Binder_init(JNIEnv* env, jobject obj)
{
JavaBBinderHolder* jbh = new JavaBBinderHolder();
if (jbh == NULL) {
jniThrowException(env, "java/lang/OutOfMemoryError", NULL);
return;
}
ALOGV("Java Binder %p: acquiring first ref on holder %p", obj, jbh);
jbh->incStrong((void*)android_os_Binder_init);
env->SetLongField(obj, gBinderOffsets.mObject, (jlong)jbh);
}
static void android_os_Binder_destroy(JNIEnv* env, jobject obj)
{
JavaBBinderHolder* jbh = (JavaBBinderHolder*)
env->GetLongField(obj, gBinderOffsets.mObject);
if (jbh != NULL) {
env->SetLongField(obj, gBinderOffsets.mObject, 0);
ALOGV("Java Binder %p: removing ref on holder %p", obj, jbh);
jbh->decStrong((void*)android_os_Binder_init);
} else {
// Encountering an uninitialized binder is harmless. All it means is that
// the Binder was only partially initialized when its finalizer ran and called
// destroy(). The Binder could be partially initialized for several reasons.
// For example, a Binder subclass constructor might have thrown an exception before
// it could delegate to its superclass's constructor. Consequently init() would
// not have been called and the holder pointer would remain NULL.
ALOGV("Java Binder %p: ignoring uninitialized binder", obj);
}
}
static void android_os_Binder_blockUntilThreadAvailable(JNIEnv* env, jobject clazz)
{
return IPCThreadState::self()->blockUntilThreadAvailable();
}
// ----------------------------------------------------------------------------
static const JNINativeMethod gBinderMethods[] = {
/* name, signature, funcPtr */
{ "getCallingPid", "()I", (void*)android_os_Binder_getCallingPid },
{ "getCallingUid", "()I", (void*)android_os_Binder_getCallingUid },
{ "clearCallingIdentity", "()J", (void*)android_os_Binder_clearCallingIdentity },
{ "restoreCallingIdentity", "(J)V", (void*)android_os_Binder_restoreCallingIdentity },
{ "setThreadStrictModePolicy", "(I)V", (void*)android_os_Binder_setThreadStrictModePolicy },
{ "getThreadStrictModePolicy", "()I", (void*)android_os_Binder_getThreadStrictModePolicy },
{ "flushPendingCommands", "()V", (void*)android_os_Binder_flushPendingCommands },
{ "init", "()V", (void*)android_os_Binder_init },
{ "destroy", "()V", (void*)android_os_Binder_destroy },
{ "blockUntilThreadAvailable", "()V", (void*)android_os_Binder_blockUntilThreadAvailable }
};
const char* const kBinderPathName = "android/os/Binder";
static int int_register_android_os_Binder(JNIEnv* env)
{
jclass clazz = FindClassOrDie(env, kBinderPathName);
gBinderOffsets.mClass = MakeGlobalRefOrDie(env, clazz);
gBinderOffsets.mExecTransact = GetMethodIDOrDie(env, clazz, "execTransact", "(IJJI)Z");
gBinderOffsets.mObject = GetFieldIDOrDie(env, clazz, "mObject", "J");
return RegisterMethodsOrDie(
env, kBinderPathName,
gBinderMethods, NELEM(gBinderMethods));
}
// ****************************************************************************
// ****************************************************************************
// ****************************************************************************
namespace android {
jint android_os_Debug_getLocalObjectCount(JNIEnv* env, jobject clazz)
{
return gNumLocalRefs;
}
jint android_os_Debug_getProxyObjectCount(JNIEnv* env, jobject clazz)
{
return gNumProxyRefs;
}
jint android_os_Debug_getDeathObjectCount(JNIEnv* env, jobject clazz)
{
return gNumDeathRefs;
}
}
// ****************************************************************************
// ****************************************************************************
// ****************************************************************************
static jobject android_os_BinderInternal_getContextObject(JNIEnv* env, jobject clazz)
{
sp<IBinder> b = ProcessState::self()->getContextObject(NULL);
return javaObjectForIBinder(env, b);
}
static void android_os_BinderInternal_joinThreadPool(JNIEnv* env, jobject clazz)
{
sp<IBinder> b = ProcessState::self()->getContextObject(NULL);
android::IPCThreadState::self()->joinThreadPool();
}
static void android_os_BinderInternal_disableBackgroundScheduling(JNIEnv* env,
jobject clazz, jboolean disable)
{
IPCThreadState::disableBackgroundScheduling(disable ? true : false);
}
static void android_os_BinderInternal_setMaxThreads(JNIEnv* env,
jobject clazz, jint maxThreads)
{
ProcessState::self()->setThreadPoolMaxThreadCount(maxThreads);
}
static void android_os_BinderInternal_handleGc(JNIEnv* env, jobject clazz)
{
ALOGV("Gc has executed, clearing binder ops");
android_atomic_and(0, &gNumRefsCreated);
}
// ----------------------------------------------------------------------------
static const JNINativeMethod gBinderInternalMethods[] = {
/* name, signature, funcPtr */
{ "getContextObject", "()Landroid/os/IBinder;", (void*)android_os_BinderInternal_getContextObject },
{ "joinThreadPool", "()V", (void*)android_os_BinderInternal_joinThreadPool },
{ "disableBackgroundScheduling", "(Z)V", (void*)android_os_BinderInternal_disableBackgroundScheduling },
{ "setMaxThreads", "(I)V", (void*)android_os_BinderInternal_setMaxThreads },
{ "handleGc", "()V", (void*)android_os_BinderInternal_handleGc }
};
const char* const kBinderInternalPathName = "com/android/internal/os/BinderInternal";
static int int_register_android_os_BinderInternal(JNIEnv* env)
{
jclass clazz = FindClassOrDie(env, kBinderInternalPathName);
gBinderInternalOffsets.mClass = MakeGlobalRefOrDie(env, clazz);
gBinderInternalOffsets.mForceGc = GetStaticMethodIDOrDie(env, clazz, "forceBinderGc", "()V");
return RegisterMethodsOrDie(
env, kBinderInternalPathName,
gBinderInternalMethods, NELEM(gBinderInternalMethods));
}
// ****************************************************************************
// ****************************************************************************
// ****************************************************************************
static jboolean android_os_BinderProxy_pingBinder(JNIEnv* env, jobject obj)
{
IBinder* target = (IBinder*)
env->GetLongField(obj, gBinderProxyOffsets.mObject);
if (target == NULL) {
return JNI_FALSE;
}
status_t err = target->pingBinder();
return err == NO_ERROR ? JNI_TRUE : JNI_FALSE;
}
static jstring android_os_BinderProxy_getInterfaceDescriptor(JNIEnv* env, jobject obj)
{
IBinder* target = (IBinder*) env->GetLongField(obj, gBinderProxyOffsets.mObject);
if (target != NULL) {
const String16& desc = target->getInterfaceDescriptor();
return env->NewString(reinterpret_cast<const jchar*>(desc.string()),
desc.size());
}
jniThrowException(env, "java/lang/RuntimeException",
"No binder found for object");
return NULL;
}
static jboolean android_os_BinderProxy_isBinderAlive(JNIEnv* env, jobject obj)
{
IBinder* target = (IBinder*)
env->GetLongField(obj, gBinderProxyOffsets.mObject);
if (target == NULL) {
return JNI_FALSE;
}
bool alive = target->isBinderAlive();
return alive ? JNI_TRUE : JNI_FALSE;
}
static int getprocname(pid_t pid, char *buf, size_t len) {
char filename[32];
FILE *f;
snprintf(filename, sizeof(filename), "/proc/%d/cmdline", pid);
f = fopen(filename, "r");
if (!f) {
*buf = '\0';
return 1;
}
if (!fgets(buf, len, f)) {
*buf = '\0';
fclose(f);
return 2;
}
fclose(f);
return 0;
}
static bool push_eventlog_string(char** pos, const char* end, const char* str) {
jint len = strlen(str);
int space_needed = 1 + sizeof(len) + len;
if (end - *pos < space_needed) {
ALOGW("not enough space for string. remain=%" PRIdPTR "; needed=%d",
end - *pos, space_needed);
return false;
}
**pos = EVENT_TYPE_STRING;
(*pos)++;
memcpy(*pos, &len, sizeof(len));
*pos += sizeof(len);
memcpy(*pos, str, len);
*pos += len;
return true;
}
static bool push_eventlog_int(char** pos, const char* end, jint val) {
int space_needed = 1 + sizeof(val);
if (end - *pos < space_needed) {
ALOGW("not enough space for int. remain=%" PRIdPTR "; needed=%d",
end - *pos, space_needed);
return false;
}
**pos = EVENT_TYPE_INT;
(*pos)++;
memcpy(*pos, &val, sizeof(val));
*pos += sizeof(val);
return true;
}
// From frameworks/base/core/java/android/content/EventLogTags.logtags:
static const bool kEnableBinderSample = false;
#define LOGTAG_BINDER_OPERATION 52004
static void conditionally_log_binder_call(int64_t start_millis,
IBinder* target, jint code) {
int duration_ms = static_cast<int>(uptimeMillis() - start_millis);
int sample_percent;
if (duration_ms >= 500) {
sample_percent = 100;
} else {
sample_percent = 100 * duration_ms / 500;
if (sample_percent == 0) {
return;
}
if (sample_percent < (random() % 100 + 1)) {
return;
}
}
char process_name[40];
getprocname(getpid(), process_name, sizeof(process_name));
String8 desc(target->getInterfaceDescriptor());
char buf[LOGGER_ENTRY_MAX_PAYLOAD];
buf[0] = EVENT_TYPE_LIST;
buf[1] = 5;
char* pos = &buf[2];
char* end = &buf[LOGGER_ENTRY_MAX_PAYLOAD - 1]; // leave room for final \n
if (!push_eventlog_string(&pos, end, desc.string())) return;
if (!push_eventlog_int(&pos, end, code)) return;
if (!push_eventlog_int(&pos, end, duration_ms)) return;
if (!push_eventlog_string(&pos, end, process_name)) return;
if (!push_eventlog_int(&pos, end, sample_percent)) return;
*(pos++) = '\n'; // conventional with EVENT_TYPE_LIST apparently.
android_bWriteLog(LOGTAG_BINDER_OPERATION, buf, pos - buf);
}
// We only measure binder call durations to potentially log them if
// we're on the main thread.
static bool should_time_binder_calls() {
return (getpid() == gettid());
}
static jboolean android_os_BinderProxy_transact(JNIEnv* env, jobject obj,
jint code, jobject dataObj, jobject replyObj, jint flags) // throws RemoteException
{
if (dataObj == NULL) {
jniThrowNullPointerException(env, NULL);
return JNI_FALSE;
}
Parcel* data = parcelForJavaObject(env, dataObj);
if (data == NULL) {
return JNI_FALSE;
}
Parcel* reply = parcelForJavaObject(env, replyObj);
if (reply == NULL && replyObj != NULL) {
return JNI_FALSE;
}
IBinder* target = (IBinder*)
env->GetLongField(obj, gBinderProxyOffsets.mObject);
if (target == NULL) {
jniThrowException(env, "java/lang/IllegalStateException", "Binder has been finalized!");
return JNI_FALSE;
}
ALOGV("Java code calling transact on %p in Java object %p with code %" PRId32 "\n",
target, obj, code);
bool time_binder_calls;
int64_t start_millis;
if (kEnableBinderSample) {
// Only log the binder call duration for things on the Java-level main thread.
// But if we don't
time_binder_calls = should_time_binder_calls();
if (time_binder_calls) {
start_millis = uptimeMillis();
}
}
//printf("Transact from Java code to %p sending: ", target); data->print();
status_t err = target->transact(code, *data, reply, flags);
//if (reply) printf("Transact from Java code to %p received: ", target); reply->print();
if (kEnableBinderSample) {
if (time_binder_calls) {
conditionally_log_binder_call(start_millis, target, code);
}
}
if (err == NO_ERROR) {
return JNI_TRUE;
} else if (err == UNKNOWN_TRANSACTION) {
return JNI_FALSE;
}
signalExceptionForError(env, obj, err, true /*canThrowRemoteException*/, data->dataSize());
return JNI_FALSE;
}
static void android_os_BinderProxy_linkToDeath(JNIEnv* env, jobject obj,
jobject recipient, jint flags) // throws RemoteException
{
if (recipient == NULL) {
jniThrowNullPointerException(env, NULL);
return;
}
IBinder* target = (IBinder*)
env->GetLongField(obj, gBinderProxyOffsets.mObject);
if (target == NULL) {
ALOGW("Binder has been finalized when calling linkToDeath() with recip=%p)\n", recipient);
assert(false);
}
LOGDEATH("linkToDeath: binder=%p recipient=%p\n", target, recipient);
if (!target->localBinder()) {
DeathRecipientList* list = (DeathRecipientList*)
env->GetLongField(obj, gBinderProxyOffsets.mOrgue);
sp<JavaDeathRecipient> jdr = new JavaDeathRecipient(env, recipient, list);
status_t err = target->linkToDeath(jdr, NULL, flags);
if (err != NO_ERROR) {
// Failure adding the death recipient, so clear its reference
// now.
jdr->clearReference();
signalExceptionForError(env, obj, err, true /*canThrowRemoteException*/);
}
}
}
static jboolean android_os_BinderProxy_unlinkToDeath(JNIEnv* env, jobject obj,
jobject recipient, jint flags)
{
jboolean res = JNI_FALSE;
if (recipient == NULL) {
jniThrowNullPointerException(env, NULL);
return res;
}
IBinder* target = (IBinder*)
env->GetLongField(obj, gBinderProxyOffsets.mObject);
if (target == NULL) {
ALOGW("Binder has been finalized when calling linkToDeath() with recip=%p)\n", recipient);
return JNI_FALSE;
}
LOGDEATH("unlinkToDeath: binder=%p recipient=%p\n", target, recipient);
if (!target->localBinder()) {
status_t err = NAME_NOT_FOUND;
// If we find the matching recipient, proceed to unlink using that
DeathRecipientList* list = (DeathRecipientList*)
env->GetLongField(obj, gBinderProxyOffsets.mOrgue);
sp<JavaDeathRecipient> origJDR = list->find(recipient);
LOGDEATH(" unlink found list %p and JDR %p", list, origJDR.get());
if (origJDR != NULL) {
wp<IBinder::DeathRecipient> dr;
err = target->unlinkToDeath(origJDR, NULL, flags, &dr);
if (err == NO_ERROR && dr != NULL) {
sp<IBinder::DeathRecipient> sdr = dr.promote();
JavaDeathRecipient* jdr = static_cast<JavaDeathRecipient*>(sdr.get());
if (jdr != NULL) {
jdr->clearReference();
}
}
}
if (err == NO_ERROR || err == DEAD_OBJECT) {
res = JNI_TRUE;
} else {
jniThrowException(env, "java/util/NoSuchElementException",
"Death link does not exist");
}
}
return res;
}
static void android_os_BinderProxy_destroy(JNIEnv* env, jobject obj)
{
// Don't race with construction/initialization
AutoMutex _l(mProxyLock);
IBinder* b = (IBinder*)
env->GetLongField(obj, gBinderProxyOffsets.mObject);
DeathRecipientList* drl = (DeathRecipientList*)
env->GetLongField(obj, gBinderProxyOffsets.mOrgue);
LOGDEATH("Destroying BinderProxy %p: binder=%p drl=%p\n", obj, b, drl);
if (b != nullptr) {
env->SetLongField(obj, gBinderProxyOffsets.mObject, 0);
env->SetLongField(obj, gBinderProxyOffsets.mOrgue, 0);
drl->decStrong((void*)javaObjectForIBinder);
b->decStrong((void*)javaObjectForIBinder);
}
IPCThreadState::self()->flushCommands();
}
// ----------------------------------------------------------------------------
static const JNINativeMethod gBinderProxyMethods[] = {
/* name, signature, funcPtr */
{"pingBinder", "()Z", (void*)android_os_BinderProxy_pingBinder},
{"isBinderAlive", "()Z", (void*)android_os_BinderProxy_isBinderAlive},
{"getInterfaceDescriptor", "()Ljava/lang/String;", (void*)android_os_BinderProxy_getInterfaceDescriptor},
{"transactNative", "(ILandroid/os/Parcel;Landroid/os/Parcel;I)Z", (void*)android_os_BinderProxy_transact},
{"linkToDeath", "(Landroid/os/IBinder$DeathRecipient;I)V", (void*)android_os_BinderProxy_linkToDeath},
{"unlinkToDeath", "(Landroid/os/IBinder$DeathRecipient;I)Z", (void*)android_os_BinderProxy_unlinkToDeath},
{"destroy", "()V", (void*)android_os_BinderProxy_destroy},
};
const char* const kBinderProxyPathName = "android/os/BinderProxy";
static int int_register_android_os_BinderProxy(JNIEnv* env)
{
jclass clazz = FindClassOrDie(env, "java/lang/Error");
gErrorOffsets.mClass = MakeGlobalRefOrDie(env, clazz);
clazz = FindClassOrDie(env, kBinderProxyPathName);
gBinderProxyOffsets.mClass = MakeGlobalRefOrDie(env, clazz);
gBinderProxyOffsets.mConstructor = GetMethodIDOrDie(env, clazz, "<init>", "()V");
gBinderProxyOffsets.mSendDeathNotice = GetStaticMethodIDOrDie(env, clazz, "sendDeathNotice",
"(Landroid/os/IBinder$DeathRecipient;)V");
gBinderProxyOffsets.mObject = GetFieldIDOrDie(env, clazz, "mObject", "J");
gBinderProxyOffsets.mSelf = GetFieldIDOrDie(env, clazz, "mSelf",
"Ljava/lang/ref/WeakReference;");
gBinderProxyOffsets.mOrgue = GetFieldIDOrDie(env, clazz, "mOrgue", "J");
clazz = FindClassOrDie(env, "java/lang/Class");
gClassOffsets.mGetName = GetMethodIDOrDie(env, clazz, "getName", "()Ljava/lang/String;");
return RegisterMethodsOrDie(
env, kBinderProxyPathName,
gBinderProxyMethods, NELEM(gBinderProxyMethods));
}
// ****************************************************************************
// ****************************************************************************
// ****************************************************************************
int register_android_os_Binder(JNIEnv* env)
{
if (int_register_android_os_Binder(env) < 0)
return -1;
if (int_register_android_os_BinderInternal(env) < 0)
return -1;
if (int_register_android_os_BinderProxy(env) < 0)
return -1;
jclass clazz = FindClassOrDie(env, "android/util/Log");
gLogOffsets.mClass = MakeGlobalRefOrDie(env, clazz);
gLogOffsets.mLogE = GetStaticMethodIDOrDie(env, clazz, "e",
"(Ljava/lang/String;Ljava/lang/String;Ljava/lang/Throwable;)I");
clazz = FindClassOrDie(env, "android/os/ParcelFileDescriptor");
gParcelFileDescriptorOffsets.mClass = MakeGlobalRefOrDie(env, clazz);
gParcelFileDescriptorOffsets.mConstructor = GetMethodIDOrDie(env, clazz, "<init>",
"(Ljava/io/FileDescriptor;)V");
clazz = FindClassOrDie(env, "android/os/StrictMode");
gStrictModeCallbackOffsets.mClass = MakeGlobalRefOrDie(env, clazz);
gStrictModeCallbackOffsets.mCallback = GetStaticMethodIDOrDie(env, clazz,
"onBinderStrictModePolicyChange", "(I)V");
return 0;
}