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/*
* 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.
*/
package android.os;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.SystemApi;
import android.app.AppOpsManager;
import android.compat.annotation.UnsupportedAppUsage;
import android.util.ExceptionUtils;
import android.util.IntArray;
import android.util.Log;
import android.util.Slog;
import com.android.internal.annotations.VisibleForTesting;
import com.android.internal.os.BinderCallHeavyHitterWatcher;
import com.android.internal.os.BinderCallHeavyHitterWatcher.BinderCallHeavyHitterListener;
import com.android.internal.os.BinderInternal;
import com.android.internal.os.BinderInternal.CallSession;
import com.android.internal.util.FastPrintWriter;
import com.android.internal.util.FunctionalUtils.ThrowingRunnable;
import com.android.internal.util.FunctionalUtils.ThrowingSupplier;
import dalvik.annotation.optimization.CriticalNative;
import libcore.io.IoUtils;
import libcore.util.NativeAllocationRegistry;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintWriter;
import java.lang.reflect.Modifier;
/**
* Base class for a remotable object, the core part of a lightweight
* remote procedure call mechanism defined by {@link IBinder}.
* This class is an implementation of IBinder that provides
* standard local implementation of such an object.
*
* Most developers will not implement this class directly, instead using the
* aidl tool to describe the desired
* interface, having it generate the appropriate Binder subclass. You can,
* however, derive directly from Binder to implement your own custom RPC
* protocol or simply instantiate a raw Binder object directly to use as a
* token that can be shared across processes.
*
*
This class is just a basic IPC primitive; it has no impact on an application's
* lifecycle, and is valid only as long as the process that created it continues to run.
* To use this correctly, you must be doing so within the context of a top-level
* application component (a {@link android.app.Service}, {@link android.app.Activity},
* or {@link android.content.ContentProvider}) that lets the system know your process
* should remain running.
*
*
You must keep in mind the situations in which your process
* could go away, and thus require that you later re-create a new Binder and re-attach
* it when the process starts again. For example, if you are using this within an
* {@link android.app.Activity}, your activity's process may be killed any time the
* activity is not started; if the activity is later re-created you will need to
* create a new Binder and hand it back to the correct place again; you need to be
* aware that your process may be started for another reason (for example to receive
* a broadcast) that will not involve re-creating the activity and thus run its code
* to create a new Binder.
*
* @see IBinder
*/
public class Binder implements IBinder {
/*
* Set this flag to true to detect anonymous, local or member classes
* that extend this Binder class and that are not static. These kind
* of classes can potentially create leaks.
*/
private static final boolean FIND_POTENTIAL_LEAKS = false;
/** @hide */
public static final boolean CHECK_PARCEL_SIZE = false;
static final String TAG = "Binder";
/** @hide */
public static boolean LOG_RUNTIME_EXCEPTION = false; // DO NOT SUBMIT WITH TRUE
/**
* Value to represents that a calling work source is not set.
*
*
This constant needs to be kept in sync with IPCThreadState::kUnsetWorkSource.
*
* @hide
*/
public static final int UNSET_WORKSOURCE = -1;
/**
* Control whether {@link #dump(FileDescriptor, PrintWriter, String[]) dump()}
* calls are allowed.
*/
private static volatile String sDumpDisabled = null;
/**
* Global transaction tracker instance for this process.
*/
private static volatile TransactionTracker sTransactionTracker = null;
/**
* Global observer for this process.
*/
private static BinderInternal.Observer sObserver = null;
/**
* Guestimate of native memory associated with a Binder.
*/
private static final int NATIVE_ALLOCATION_SIZE = 500;
private static native long getNativeFinalizer();
// Use a Holder to allow static initialization of Binder in the boot image, and
// possibly to avoid some initialization ordering issues.
private static class NoImagePreloadHolder {
public static final NativeAllocationRegistry sRegistry = new NativeAllocationRegistry(
Binder.class.getClassLoader(), getNativeFinalizer(), NATIVE_ALLOCATION_SIZE);
}
/**
* The watcher to monitor the heavy hitter from incoming transactions
*/
private static volatile BinderCallHeavyHitterWatcher sHeavyHitterWatcher = null;
// Transaction tracking code.
/**
* Flag indicating whether we should be tracing transact calls.
*/
private static volatile boolean sStackTrackingEnabled = false;
private static final Object sTracingUidsWriteLock = new Object();
private static volatile IntArray sTracingUidsImmutable = new IntArray();
/**
* Enable Binder IPC stack tracking. If enabled, every binder transaction will be logged to
* {@link TransactionTracker}.
*
* @hide
*/
public static void enableStackTracking() {
sStackTrackingEnabled = true;
}
/**
* Disable Binder IPC stack tracking.
*
* @hide
*/
public static void disableStackTracking() {
sStackTrackingEnabled = false;
}
/**
* @hide
*/
public static void enableTracingForUid(int uid) {
synchronized (sTracingUidsWriteLock) {
final IntArray copy = sTracingUidsImmutable.clone();
copy.add(uid);
sTracingUidsImmutable = copy;
}
}
/**
* Check if binder transaction stack tracking is enabled.
*
* @hide
*/
public static boolean isStackTrackingEnabled() {
return sStackTrackingEnabled;
}
/**
* @hide
*/
public static boolean isTracingEnabled(int callingUid) {
return sTracingUidsImmutable.indexOf(callingUid) != -1;
}
/**
* Get the binder transaction tracker for this process.
*
* @hide
*/
public synchronized static TransactionTracker getTransactionTracker() {
if (sTransactionTracker == null)
sTransactionTracker = new TransactionTracker();
return sTransactionTracker;
}
/**
* Get the binder transaction observer for this process.
*
* @hide
*/
public static void setObserver(@Nullable BinderInternal.Observer observer) {
sObserver = observer;
}
/** @hide */
static volatile boolean sWarnOnBlocking = false;
/**
* Warn if any blocking binder transactions are made out from this process.
* This is typically only useful for the system process, to prevent it from
* blocking on calls to external untrusted code. Instead, all outgoing calls
* that require a result must be sent as {@link IBinder#FLAG_ONEWAY} calls
* which deliver results through a callback interface.
*
* @hide
*/
public static void setWarnOnBlocking(boolean warnOnBlocking) {
sWarnOnBlocking = warnOnBlocking;
}
/**
* Allow blocking calls on the given interface, overriding the requested
* value of {@link #setWarnOnBlocking(boolean)}.
*
*
This should only be rarely called when you are absolutely sure
* the remote interface is a built-in system component that can never be
* upgraded. In particular, this must never be called for
* interfaces hosted by package that could be upgraded or replaced,
* otherwise you risk system instability if that remote interface wedges.
*
* @hide
*/
public static IBinder allowBlocking(IBinder binder) {
try {
if (binder instanceof BinderProxy) {
((BinderProxy) binder).mWarnOnBlocking = false;
} else if (binder != null && binder.getInterfaceDescriptor() != null
&& binder.queryLocalInterface(binder.getInterfaceDescriptor()) == null) {
Log.w(TAG, "Unable to allow blocking on interface " + binder);
}
} catch (RemoteException ignored) {
}
return binder;
}
/**
* Reset the given interface back to the default blocking behavior,
* reverting any changes made by {@link #allowBlocking(IBinder)}.
*
* @hide
*/
public static IBinder defaultBlocking(IBinder binder) {
if (binder instanceof BinderProxy) {
((BinderProxy) binder).mWarnOnBlocking = sWarnOnBlocking;
}
return binder;
}
/**
* Inherit the current {@link #allowBlocking(IBinder)} value from one given
* interface to another.
*
* @hide
*/
public static void copyAllowBlocking(IBinder fromBinder, IBinder toBinder) {
if (fromBinder instanceof BinderProxy && toBinder instanceof BinderProxy) {
((BinderProxy) toBinder).mWarnOnBlocking = ((BinderProxy) fromBinder).mWarnOnBlocking;
}
}
static ThreadLocal sWarnOnBlockingOnCurrentThread =
ThreadLocal.withInitial(() -> sWarnOnBlocking);
/**
* Allow blocking calls for the current thread.
*
* @see {@link #allowBlocking}.
*
* @hide
*/
public static void allowBlockingForCurrentThread() {
sWarnOnBlockingOnCurrentThread.set(false);
}
/**
* Reset the current thread to the default blocking behavior.
*
* @see {@link #defaultBlocking}.
*
* @hide
*/
public static void defaultBlockingForCurrentThread() {
sWarnOnBlockingOnCurrentThread.set(sWarnOnBlocking);
}
/**
* Raw native pointer to JavaBBinderHolder object. Owned by this Java object. Not null.
*/
@UnsupportedAppUsage
private final long mObject;
private IInterface mOwner;
@Nullable
private String mDescriptor;
private volatile String[] mTransactionTraceNames = null;
private volatile String mSimpleDescriptor = null;
private static final int TRANSACTION_TRACE_NAME_ID_LIMIT = 1024;
/**
* Return the ID of the process that sent you the current transaction
* that is being processed. This PID can be used with higher-level
* system services to determine its identity and check permissions.
* If the current thread is not currently executing an incoming transaction,
* then its own PID is returned.
*
* Warning: oneway transactions do not receive PID.
*/
@CriticalNative
public static final native int getCallingPid();
/**
* Return the Linux UID assigned to the process that sent you the
* current transaction that is being processed. This UID can be used with
* higher-level system services to determine its identity and check
* permissions. If the current thread is not currently executing an
* incoming transaction, then its own UID is returned.
*/
@CriticalNative
public static final native int getCallingUid();
/**
* Returns {@code true} if the current thread is currently executing an
* incoming transaction.
*
* @hide
*/
@CriticalNative
public static final native boolean isDirectlyHandlingTransaction();
/**
* Return the Linux UID assigned to the process that sent the transaction
* currently being processed.
*
* @throws IllegalStateException if the current thread is not currently
* executing an incoming transaction.
*/
public static final int getCallingUidOrThrow() {
if (!isDirectlyHandlingTransaction()) {
throw new IllegalStateException(
"Thread is not in a binder transcation");
}
return getCallingUid();
}
/**
* Return the UserHandle assigned to the process that sent you the
* current transaction that is being processed. This is the user
* of the caller. It is distinct from {@link #getCallingUid()} in that a
* particular user will have multiple distinct apps running under it each
* with their own UID. If the current thread is not currently executing an
* incoming transaction, then its own UserHandle is returned.
*
* @see UserHandle
*/
public static final @NonNull UserHandle getCallingUserHandle() {
return UserHandle.of(UserHandle.getUserId(getCallingUid()));
}
/**
* Reset the identity of the incoming IPC on the current thread. This can
* be useful if, while handling an incoming call, you will be calling
* on interfaces of other objects that may be local to your process and
* need to do permission checks on the calls coming into them (so they
* will check the permission of your own local process, and not whatever
* process originally called you).
*
* @return Returns an opaque token that can be used to restore the
* original calling identity by passing it to
* {@link #restoreCallingIdentity(long)}.
*
* @see #getCallingPid()
* @see #getCallingUid()
* @see #restoreCallingIdentity(long)
*/
@CriticalNative
public static final native long clearCallingIdentity();
/**
* Restore the identity of the incoming IPC on the current thread
* back to a previously identity that was returned by {@link
* #clearCallingIdentity}.
*
* @param token The opaque token that was previously returned by
* {@link #clearCallingIdentity}.
*
* @see #clearCallingIdentity
*/
@CriticalNative
public static final native void restoreCallingIdentity(long token);
/**
* Convenience method for running the provided action enclosed in
* {@link #clearCallingIdentity}/{@link #restoreCallingIdentity}.
*
* Any exception thrown by the given action will be caught and
* rethrown after the call to {@link #restoreCallingIdentity}.
*
* @hide
*/
public static final void withCleanCallingIdentity(@NonNull ThrowingRunnable action) {
Throwable throwableToPropagate = null;
final long callingIdentity = clearCallingIdentity();
try {
action.runOrThrow();
} catch (Throwable throwable) {
throwableToPropagate = throwable;
} finally {
restoreCallingIdentity(callingIdentity);
if (throwableToPropagate != null) {
throw ExceptionUtils.propagate(throwableToPropagate);
}
}
}
/**
* Convenience method for running the provided action enclosed in
* {@link #clearCallingIdentity}/{@link #restoreCallingIdentity} returning the result.
*
*
Any exception thrown by the given action will be caught and rethrown after
* the call to {@link #restoreCallingIdentity}.
*
* @hide
*/
public static final T withCleanCallingIdentity(@NonNull ThrowingSupplier action) {
Throwable throwableToPropagate = null;
final long callingIdentity = clearCallingIdentity();
try {
return action.getOrThrow();
} catch (Throwable throwable) {
throwableToPropagate = throwable;
return null; // overridden by throwing in finally block
} finally {
restoreCallingIdentity(callingIdentity);
if (throwableToPropagate != null) {
throw ExceptionUtils.propagate(throwableToPropagate);
}
}
}
/**
* Sets the native thread-local StrictMode policy mask.
*
* The StrictMode settings are kept in two places: a Java-level
* threadlocal for libcore/Dalvik, and a native threadlocal (set
* here) for propagation via Binder calls. This is a little
* unfortunate, but necessary to break otherwise more unfortunate
* dependencies either of Dalvik on Android, or Android
* native-only code on Dalvik.
*
* @see StrictMode
*
* @hide
*/
@CriticalNative
public static final native void setThreadStrictModePolicy(int policyMask);
/**
* Gets the current native thread-local StrictMode policy mask.
*
* @see #setThreadStrictModePolicy
*
* @hide
*/
@CriticalNative
public static final native int getThreadStrictModePolicy();
/**
* Sets the work source for this thread.
*
*
All the following binder calls on this thread will use the provided work source. If this
* is called during an on-going binder transaction, all the following binder calls will use the
* work source until the end of the transaction.
*
*
The concept of worksource is similar to {@link WorkSource}. However, for performance
* reasons, we only support one UID. This UID represents the original user responsible for the
* binder calls.
*
*
{@link #restoreCallingWorkSource(long)} must always be called after setting the
* worksource.
*
*
A typical use case would be
*
* long token = Binder.setCallingWorkSourceUid(uid);
* try {
* // Call an API.
* } finally {
* Binder.restoreCallingWorkSource(token);
* }
*
*
* The work source will be propagated for future outgoing binder transactions
* executed on this thread.
*
* @param workSource The original UID responsible for the binder call.
* @return token to restore original work source.
*/
@CriticalNative
public static final native long setCallingWorkSourceUid(int workSource);
/**
* Returns the work source set by the caller.
*
*
Unlike {@link #getCallingUid()}, this result of this method cannot be trusted. The
* caller can set the value to whatever they want. Only use this value if you trust the calling
* UID.
*
* @return The original UID responsible for the binder transaction.
*/
@CriticalNative
public static final native int getCallingWorkSourceUid();
/**
* Clears the work source on this thread.
*
*
The work source will be propagated for future outgoing binder transactions
* executed on this thread.
*
*
{@link #restoreCallingWorkSource(long)} must always be called after clearing the
* worksource.
*
*
A typical use case would be
*
* long token = Binder.clearCallingWorkSource();
* try {
* // Call an API.
* } finally {
* Binder.restoreCallingWorkSource(token);
* }
*
*
* @return token to restore original work source.
*/
@CriticalNative
public static final native long clearCallingWorkSource();
/**
* Restores the work source on this thread using a token returned by
* {@link #setCallingWorkSourceUid(int)} or {@link #clearCallingWorkSource()}.
*
* A typical use case would be
*
* long token = Binder.setCallingWorkSourceUid(uid);
* try {
* // Call an API.
* } finally {
* Binder.restoreCallingWorkSource(token);
* }
*
*/
@CriticalNative
public static final native void restoreCallingWorkSource(long token);
/**
* Mark as being built with VINTF-level stability promise. This API should
* only ever be invoked by generated code from the aidl compiler. It means
* that the interface represented by this binder is guaranteed to be kept
* stable for several years, according to the VINTF compatibility lifecycle,
* and the build system also keeps snapshots of these APIs and invokes the
* AIDL compiler to make sure that these snapshots are backwards compatible.
* Instead of using this API, use the @VintfStability annotation on your
* AIDL interface.
*
* @hide
*/
@SystemApi(client = SystemApi.Client.MODULE_LIBRARIES)
public final native void markVintfStability();
/**
* Use a VINTF-stability binder w/o VINTF requirements. Should be called
* on a binder before it is sent out of process.
*
* This must be called before the object is sent to another process.
*
* @hide
*/
public final native void forceDowngradeToSystemStability();
/**
* Flush any Binder commands pending in the current thread to the kernel
* driver. This can be
* useful to call before performing an operation that may block for a long
* time, to ensure that any pending object references have been released
* in order to prevent the process from holding on to objects longer than
* it needs to.
*/
public static final native void flushPendingCommands();
/**
* Add the calling thread to the IPC thread pool. This function does
* not return until the current process is exiting.
*/
public static final void joinThreadPool() {
BinderInternal.joinThreadPool();
}
/**
* Returns true if the specified interface is a proxy.
*
* @hide
*/
public static final boolean isProxy(IInterface iface) {
return iface.asBinder() != iface;
}
/**
* Call blocks until the number of executing binder threads is less
* than the maximum number of binder threads allowed for this process.
*
* @hide
*/
public static final native void blockUntilThreadAvailable();
/**
* Default constructor just initializes the object.
*
*
If you're creating a Binder token (a Binder object without an attached interface),
* you should use {@link #Binder(String)} instead.
*/
public Binder() {
this(null);
}
/**
* Constructor for creating a raw Binder object (token) along with a descriptor.
*
*
The descriptor of binder objects usually specifies the interface they are implementing.
* In case of binder tokens, no interface is implemented, and the descriptor can be used
* as a sort of tag to help identify the binder token. This will help identify remote
* references to these objects more easily when debugging.
*
* @param descriptor Used to identify the creator of this token, for example the class name.
* Instead of creating multiple tokens with the same descriptor, consider adding a suffix to
* help identify them.
*/
public Binder(@Nullable String descriptor) {
mObject = getNativeBBinderHolder();
NoImagePreloadHolder.sRegistry.registerNativeAllocation(this, mObject);
if (FIND_POTENTIAL_LEAKS) {
final Class klass = getClass();
if ((klass.isAnonymousClass() || klass.isMemberClass() || klass.isLocalClass()) &&
(klass.getModifiers() & Modifier.STATIC) == 0) {
Log.w(TAG, "The following Binder class should be static or leaks might occur: " +
klass.getCanonicalName());
}
}
mDescriptor = descriptor;
}
/**
* Convenience method for associating a specific interface with the Binder.
* After calling, {@link #queryLocalInterface(String) queryLocalInterface()}
* will be implemented for you to return the given owner IInterface when
* the corresponding descriptor is requested.
*/
public void attachInterface(@Nullable IInterface owner, @Nullable String descriptor) {
mOwner = owner;
mDescriptor = descriptor;
}
/**
* Default implementation returns an empty interface name.
*/
public @Nullable String getInterfaceDescriptor() {
return mDescriptor;
}
/**
* Default implementation always returns true -- if you got here,
* the object is alive.
*/
public boolean pingBinder() {
return true;
}
/**
* {@inheritDoc}
*
* Note that if you're calling on a local binder, this always returns true
* because your process is alive if you're calling it.
*/
public boolean isBinderAlive() {
return true;
}
/**
* Use information supplied to {@link #attachInterface attachInterface()}
* to return the associated {@link IInterface} if it matches the requested
* descriptor.
*/
public @Nullable IInterface queryLocalInterface(@NonNull String descriptor) {
if (mDescriptor != null && mDescriptor.equals(descriptor)) {
return mOwner;
}
return null;
}
/**
* Control disabling of dump calls in this process. This is used by the system
* process watchdog to disable incoming dump calls while it has detecting the system
* is hung and is reporting that back to the activity controller. This is to
* prevent the controller from getting hung up on bug reports at this point.
*
* @param msg The message to show instead of the dump; if null, dumps are
* re-enabled.
*
* @hide
*/
public static void setDumpDisabled(String msg) {
sDumpDisabled = msg;
}
/**
* Listener to be notified about each proxy-side binder call.
*
* @see {@link #setProxyTransactListener}.
*
* @hide
*/
@SystemApi
public interface ProxyTransactListener {
/**
* Called before onTransact.
*
* @return an object that will be passed back to {@link #onTransactEnded} (or null).,
*
* @hide
*/
@Nullable
default Object onTransactStarted(@NonNull IBinder binder, int transactionCode, int flags) {
return onTransactStarted(binder, transactionCode);
}
/**
* Called before onTransact.
*
* @return an object that will be passed back to {@link #onTransactEnded} (or null).
*/
@Nullable
Object onTransactStarted(@NonNull IBinder binder, int transactionCode);
/**
* Called after onTransact (even when an exception is thrown).
*
* @param session The object return by {@link #onTransactStarted}.
*/
void onTransactEnded(@Nullable Object session);
}
/**
* Propagates the work source to binder calls executed by the system server.
*
*
By default, this listener will propagate the worksource if the outgoing call happens on
* the same thread as the incoming binder call.
* Custom attribution can be done by calling {@link ThreadLocalWorkSource#setUid(int)}.
*
* @hide
*/
public static class PropagateWorkSourceTransactListener implements ProxyTransactListener {
@Override
public Object onTransactStarted(IBinder binder, int transactionCode) {
// Note that {@link #getCallingUid()} is already set to the UID of the current
// process when this method is called.
//
// We use {@link ThreadLocalWorkSource} instead. It also allows feature owners to set
// {@link ThreadLocalWorkSource#set(int)} manually to attribute resources to a UID.
int uid = ThreadLocalWorkSource.getUid();
if (uid != ThreadLocalWorkSource.UID_NONE) {
return Binder.setCallingWorkSourceUid(uid);
}
return null;
}
@Override
public void onTransactEnded(Object session) {
if (session != null) {
long token = (long) session;
Binder.restoreCallingWorkSource(token);
}
}
}
/**
* Sets a listener for the transact method on the proxy-side.
*
* The listener is global. Only fast operations should be done to avoid thread
* contentions.
* The listener implementation needs to handle synchronization if needed. The methods on the
* listener can be called concurrently.
* Listener set will be used for new transactions. On-going transaction will still use the
* previous listener (if already set).
* The listener is called on the critical path of the binder transaction so be careful about
* performance.
* Never execute another binder transaction inside the listener.
*
* @hide
*/
@SystemApi
public static void setProxyTransactListener(@Nullable ProxyTransactListener listener) {
BinderProxy.setTransactListener(listener);
}
/**
* Default implementation is a stub that returns false. You will want
* to override this to do the appropriate unmarshalling of transactions.
*
* If you want to call this, call transact().
*
*
Implementations that are returning a result should generally use
* {@link Parcel#writeNoException() Parcel.writeNoException} and
* {@link Parcel#writeException(Exception) Parcel.writeException} to propagate
* exceptions back to the caller.
*
* @param code The action to perform. This should be a number between
* {@link #FIRST_CALL_TRANSACTION} and {@link #LAST_CALL_TRANSACTION}.
* @param data Marshalled data being received from the caller.
* @param reply If the caller is expecting a result back, it should be marshalled
* in to here.
* @param flags Additional operation flags. Either 0 for a normal
* RPC, or {@link #FLAG_ONEWAY} for a one-way RPC.
*
* @return Return true on a successful call; returning false is generally used to
* indicate that you did not understand the transaction code.
*/
protected boolean onTransact(int code, @NonNull Parcel data, @Nullable Parcel reply,
int flags) throws RemoteException {
if (code == INTERFACE_TRANSACTION) {
reply.writeString(getInterfaceDescriptor());
return true;
} else if (code == DUMP_TRANSACTION) {
ParcelFileDescriptor fd = data.readFileDescriptor();
String[] args = data.readStringArray();
if (fd != null) {
try {
dump(fd.getFileDescriptor(), args);
} finally {
IoUtils.closeQuietly(fd);
}
}
// Write the StrictMode header.
if (reply != null) {
reply.writeNoException();
} else {
StrictMode.clearGatheredViolations();
}
return true;
} else if (code == SHELL_COMMAND_TRANSACTION) {
ParcelFileDescriptor in = data.readFileDescriptor();
ParcelFileDescriptor out = data.readFileDescriptor();
ParcelFileDescriptor err = data.readFileDescriptor();
String[] args = data.readStringArray();
ShellCallback shellCallback = ShellCallback.CREATOR.createFromParcel(data);
ResultReceiver resultReceiver = ResultReceiver.CREATOR.createFromParcel(data);
try {
if (out != null) {
shellCommand(in != null ? in.getFileDescriptor() : null,
out.getFileDescriptor(),
err != null ? err.getFileDescriptor() : out.getFileDescriptor(),
args, shellCallback, resultReceiver);
}
} finally {
IoUtils.closeQuietly(in);
IoUtils.closeQuietly(out);
IoUtils.closeQuietly(err);
// Write the StrictMode header.
if (reply != null) {
reply.writeNoException();
} else {
StrictMode.clearGatheredViolations();
}
}
return true;
}
return false;
}
/**
* Resolves a transaction code to a human readable name.
*
*
Default implementation is a stub that returns null.
*
*
AIDL generated code will return the original method name.
*
* @param transactionCode The code to resolve.
* @return A human readable name.
*
* @hide
*/
public @Nullable String getTransactionName(int transactionCode) {
return null;
}
/**
* @hide
*/
@VisibleForTesting
public final @NonNull String getTransactionTraceName(int transactionCode) {
if (mTransactionTraceNames == null) {
final String descriptor = getSimpleDescriptor();
final int highestId = Math.min(getMaxTransactionId(), TRANSACTION_TRACE_NAME_ID_LIMIT);
final String[] transactionNames = new String[highestId + 1];
final StringBuffer buf = new StringBuffer();
for (int i = 0; i <= highestId; i++) {
String transactionName = getTransactionName(i + FIRST_CALL_TRANSACTION);
if (transactionName != null) {
buf.append(descriptor).append(':').append(transactionName);
} else {
buf.append(descriptor).append('#').append(i + FIRST_CALL_TRANSACTION);
}
transactionNames[i] = buf.toString();
buf.setLength(0);
}
mSimpleDescriptor = descriptor;
mTransactionTraceNames = transactionNames;
}
final int index = transactionCode - FIRST_CALL_TRANSACTION;
if (index < 0 || index >= mTransactionTraceNames.length) {
return mSimpleDescriptor + "#" + transactionCode;
}
return mTransactionTraceNames[index];
}
private @NonNull String getSimpleDescriptor() {
String descriptor = mDescriptor;
if (descriptor == null) {
// Just "Binder" to avoid null checks in transaction name tracing.
return "Binder";
}
final int dot = descriptor.lastIndexOf(".");
if (dot > 0) {
// Strip the package name
return descriptor.substring(dot + 1);
}
return descriptor;
}
/**
* @return The highest user-defined transaction id of all transactions.
* @hide
*/
public int getMaxTransactionId() {
return 0;
}
/**
* Implemented to call the more convenient version
* {@link #dump(FileDescriptor, PrintWriter, String[])}.
*/
public void dump(@NonNull FileDescriptor fd, @Nullable String[] args) {
FileOutputStream fout = new FileOutputStream(fd);
PrintWriter pw = new FastPrintWriter(fout);
try {
doDump(fd, pw, args);
} finally {
pw.flush();
}
}
void doDump(FileDescriptor fd, PrintWriter pw, String[] args) {
final String disabled = sDumpDisabled;
if (disabled == null) {
try {
dump(fd, pw, args);
} catch (SecurityException e) {
pw.println("Security exception: " + e.getMessage());
throw e;
} catch (Throwable e) {
// Unlike usual calls, in this case if an exception gets thrown
// back to us we want to print it back in to the dump data, since
// that is where the caller expects all interesting information to
// go.
pw.println();
pw.println("Exception occurred while dumping:");
e.printStackTrace(pw);
}
} else {
pw.println(sDumpDisabled);
}
}
/**
* Like {@link #dump(FileDescriptor, String[])}, but ensures the target
* executes asynchronously.
*/
public void dumpAsync(@NonNull final FileDescriptor fd, @Nullable final String[] args) {
final FileOutputStream fout = new FileOutputStream(fd);
final PrintWriter pw = new FastPrintWriter(fout);
Thread thr = new Thread("Binder.dumpAsync") {
public void run() {
try {
dump(fd, pw, args);
} finally {
pw.flush();
}
}
};
thr.start();
}
/**
* Print the object's state into the given stream.
*
* @param fd The raw file descriptor that the dump is being sent to.
* @param fout The file to which you should dump your state. This will be
* closed for you after you return.
* @param args additional arguments to the dump request.
*/
protected void dump(@NonNull FileDescriptor fd, @NonNull PrintWriter fout,
@Nullable String[] args) {
}
/**
* @param in The raw file descriptor that an input data stream can be read from.
* @param out The raw file descriptor that normal command messages should be written to.
* @param err The raw file descriptor that command error messages should be written to.
* @param args Command-line arguments.
* @param callback Callback through which to interact with the invoking shell.
* @param resultReceiver Called when the command has finished executing, with the result code.
* @throws RemoteException
*
* @hide
*/
public void shellCommand(@Nullable FileDescriptor in, @Nullable FileDescriptor out,
@Nullable FileDescriptor err,
@NonNull String[] args, @Nullable ShellCallback callback,
@NonNull ResultReceiver resultReceiver) throws RemoteException {
onShellCommand(in, out, err, args, callback, resultReceiver);
}
/**
* Handle a call to {@link #shellCommand}.
*
*
The default implementation performs a caller check to make sure the caller UID is of
* SHELL or ROOT, and then call {@link #handleShellCommand}.
*
*
Note: no permission checking is done before calling this method; you must
* apply any security checks as appropriate for the command being executed.
* Consider using {@link ShellCommand} to help in the implementation.
*
* @hide
*/
public void onShellCommand(@Nullable FileDescriptor in, @Nullable FileDescriptor out,
@Nullable FileDescriptor err,
@NonNull String[] args, @Nullable ShellCallback callback,
@NonNull ResultReceiver resultReceiver) throws RemoteException {
final int callingUid = Binder.getCallingUid();
if (callingUid != Process.ROOT_UID && callingUid != Process.SHELL_UID) {
resultReceiver.send(-1, null);
throw new SecurityException("Shell commands are only callable by ADB");
}
// First, convert in, out and err to @NonNull, by redirecting any that's null to /dev/null.
try {
if (in == null) {
in = new FileInputStream("/dev/null").getFD();
}
if (out == null) {
out = new FileOutputStream("/dev/null").getFD();
}
if (err == null) {
err = out;
}
} catch (IOException e) {
PrintWriter pw = new FastPrintWriter(new FileOutputStream(err != null ? err : out));
pw.println("Failed to open /dev/null: " + e.getMessage());
pw.flush();
resultReceiver.send(-1, null);
return;
}
// Also make args @NonNull.
if (args == null) {
args = new String[0];
}
int result = -1;
try (ParcelFileDescriptor inPfd = ParcelFileDescriptor.dup(in);
ParcelFileDescriptor outPfd = ParcelFileDescriptor.dup(out);
ParcelFileDescriptor errPfd = ParcelFileDescriptor.dup(err)) {
result = handleShellCommand(inPfd, outPfd, errPfd, args);
} catch (IOException e) {
PrintWriter pw = new FastPrintWriter(new FileOutputStream(err));
pw.println("dup() failed: " + e.getMessage());
pw.flush();
} finally {
resultReceiver.send(result, null);
}
}
/**
* System services can implement this method to implement ADB shell commands.
*
*
A system binder service can implement it to handle shell commands on ADB. For example,
* the Job Scheduler service implements it to handle {@code adb shell cmd jobscheduler}.
*
*
Commands are only executable by ADB shell; i.e. only {@link Process#SHELL_UID} and
* {@link Process#ROOT_UID} can call them.
*
* @param in standard input
* @param out standard output
* @param err standard error
* @param args arguments passed to the command. Can be empty. The first argument is typically
* a subcommand, such as {@code run} for {@code adb shell cmd jobscheduler run}.
* @return the status code returned from the {@code cmd} command.
*
* @hide
*/
@SystemApi
public int handleShellCommand(@NonNull ParcelFileDescriptor in,
@NonNull ParcelFileDescriptor out, @NonNull ParcelFileDescriptor err,
@NonNull String[] args) {
FileOutputStream ferr = new FileOutputStream(err.getFileDescriptor());
PrintWriter pw = new FastPrintWriter(ferr);
pw.println("No shell command implementation.");
pw.flush();
return 0;
}
/** @hide */
@Override
public final native @Nullable IBinder getExtension();
/**
* Set the binder extension.
* This should be called immediately when the object is created.
*
* @hide
*/
public final native void setExtension(@Nullable IBinder extension);
/**
* Default implementation rewinds the parcels and calls onTransact. On
* the remote side, transact calls into the binder to do the IPC.
*/
public final boolean transact(int code, @NonNull Parcel data, @Nullable Parcel reply,
int flags) throws RemoteException {
if (false) Log.v("Binder", "Transact: " + code + " to " + this);
if (data != null) {
data.setDataPosition(0);
}
boolean r = onTransact(code, data, reply, flags);
if (reply != null) {
reply.setDataPosition(0);
}
return r;
}
/**
* Local implementation is a no-op.
*/
public void linkToDeath(@NonNull DeathRecipient recipient, int flags) {
}
/**
* Local implementation is a no-op.
*/
public boolean unlinkToDeath(@NonNull DeathRecipient recipient, int flags) {
return true;
}
static void checkParcel(IBinder obj, int code, Parcel parcel, String msg) {
if (CHECK_PARCEL_SIZE && parcel.dataSize() >= 800*1024) {
// Trying to send > 800k, this is way too much.
StringBuilder sb = new StringBuilder();
sb.append(msg);
sb.append(": on ");
sb.append(obj);
sb.append(" calling ");
sb.append(code);
sb.append(" size ");
sb.append(parcel.dataSize());
sb.append(" (data: ");
parcel.setDataPosition(0);
sb.append(parcel.readInt());
sb.append(", ");
sb.append(parcel.readInt());
sb.append(", ");
sb.append(parcel.readInt());
sb.append(")");
Slog.wtfStack(TAG, sb.toString());
}
}
private static native long getNativeBBinderHolder();
/**
* By default, we use the calling UID since we can always trust it.
*/
private static volatile BinderInternal.WorkSourceProvider sWorkSourceProvider =
(x) -> Binder.getCallingUid();
/**
* Sets the work source provider.
*
*
The callback is global. Only fast operations should be done to avoid thread
* contentions.
* The callback implementation needs to handle synchronization if needed. The methods on the
* callback can be called concurrently.
* The callback is called on the critical path of the binder transaction so be careful about
* performance.
* Never execute another binder transaction inside the callback.
*
* @hide
*/
public static void setWorkSourceProvider(BinderInternal.WorkSourceProvider workSourceProvider) {
if (workSourceProvider == null) {
throw new IllegalArgumentException("workSourceProvider cannot be null");
}
sWorkSourceProvider = workSourceProvider;
}
// Entry point from android_util_Binder.cpp's onTransact.
@UnsupportedAppUsage
private boolean execTransact(int code, long dataObj, long replyObj,
int flags) {
// At that point, the parcel request headers haven't been parsed so we do not know what
// {@link WorkSource} the caller has set. Use calling UID as the default.
final int callingUid = Binder.getCallingUid();
final long origWorkSource = ThreadLocalWorkSource.setUid(callingUid);
try {
return execTransactInternal(code, dataObj, replyObj, flags, callingUid);
} finally {
ThreadLocalWorkSource.restore(origWorkSource);
}
}
private boolean execTransactInternal(int code, long dataObj, long replyObj, int flags,
int callingUid) {
// Make sure the observer won't change while processing a transaction.
final BinderInternal.Observer observer = sObserver;
final CallSession callSession =
observer != null ? observer.callStarted(this, code, UNSET_WORKSOURCE) : null;
Parcel data = Parcel.obtain(dataObj);
Parcel reply = Parcel.obtain(replyObj);
// Theoretically, we should call transact, which will call onTransact,
// but all that does is rewind it, and we just got these from an IPC,
// so we'll just call it directly.
boolean res;
// Log any exceptions as warnings, don't silently suppress them.
// If the call was {@link IBinder#FLAG_ONEWAY} then these exceptions
// disappear into the ether.
final boolean tracingEnabled = Trace.isTagEnabled(Trace.TRACE_TAG_AIDL) &&
(Binder.isStackTrackingEnabled() || Binder.isTracingEnabled(callingUid));
try {
final BinderCallHeavyHitterWatcher heavyHitterWatcher = sHeavyHitterWatcher;
if (heavyHitterWatcher != null) {
// Notify the heavy hitter watcher, if it's enabled.
heavyHitterWatcher.onTransaction(callingUid, getClass(), code);
}
if (tracingEnabled) {
Trace.traceBegin(Trace.TRACE_TAG_AIDL, getTransactionTraceName(code));
}
if ((flags & FLAG_COLLECT_NOTED_APP_OPS) != 0) {
AppOpsManager.startNotedAppOpsCollection(callingUid);
try {
res = onTransact(code, data, reply, flags);
} finally {
AppOpsManager.finishNotedAppOpsCollection();
}
} else {
res = onTransact(code, data, reply, flags);
}
} catch (RemoteException|RuntimeException e) {
if (observer != null) {
observer.callThrewException(callSession, e);
}
if (LOG_RUNTIME_EXCEPTION) {
Log.w(TAG, "Caught a RuntimeException from the binder stub implementation.", e);
}
if ((flags & FLAG_ONEWAY) != 0) {
if (e instanceof RemoteException) {
Log.w(TAG, "Binder call failed.", e);
} else {
Log.w(TAG, "Caught a RuntimeException from the binder stub implementation.", e);
}
} else {
// Clear the parcel before writing the exception.
reply.setDataSize(0);
reply.setDataPosition(0);
reply.writeException(e);
}
res = true;
} finally {
if (tracingEnabled) {
Trace.traceEnd(Trace.TRACE_TAG_AIDL);
}
if (observer != null) {
// The parcel RPC headers have been called during onTransact so we can now access
// the worksource UID from the parcel.
final int workSourceUid = sWorkSourceProvider.resolveWorkSourceUid(
data.readCallingWorkSourceUid());
observer.callEnded(callSession, data.dataSize(), reply.dataSize(), workSourceUid);
}
checkParcel(this, code, reply, "Unreasonably large binder reply buffer");
reply.recycle();
data.recycle();
}
// Just in case -- we are done with the IPC, so there should be no more strict
// mode violations that have gathered for this thread. Either they have been
// parceled and are now in transport off to the caller, or we are returning back
// to the main transaction loop to wait for another incoming transaction. Either
// way, strict mode begone!
StrictMode.clearGatheredViolations();
return res;
}
/**
* Set the configuration for the heavy hitter watcher.
*
* @hide
*/
public static synchronized void setHeavyHitterWatcherConfig(final boolean enabled,
final int batchSize, final float threshold,
@Nullable final BinderCallHeavyHitterListener listener) {
Slog.i(TAG, "Setting heavy hitter watcher config: "
+ enabled + ", " + batchSize + ", " + threshold);
BinderCallHeavyHitterWatcher watcher = sHeavyHitterWatcher;
if (enabled) {
if (listener == null) {
throw new IllegalArgumentException();
}
boolean newWatcher = false;
if (watcher == null) {
watcher = BinderCallHeavyHitterWatcher.getInstance();
newWatcher = true;
}
watcher.setConfig(true, batchSize, threshold, listener);
if (newWatcher) {
sHeavyHitterWatcher = watcher;
}
} else if (watcher != null) {
watcher.setConfig(false, 0, 0.0f, null);
}
}
}