/* * Copyright (C) 2005 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. */ #pragma once #include #include #include #include #if defined(_WIN32) typedef int uid_t; #endif // --------------------------------------------------------------------------- namespace android { class IPCThreadState { public: using CallRestriction = ProcessState::CallRestriction; static IPCThreadState* self(); static IPCThreadState* selfOrNull(); // self(), but won't instantiate // Freeze or unfreeze the binder interface to a specific process. When freezing, this method // will block up to timeout_ms to process pending transactions directed to pid. Unfreeze // is immediate. Transactions to processes frozen via this method won't be delivered and the // driver will return BR_FROZEN_REPLY to the client sending them. After unfreeze, // transactions will be delivered normally. // // pid: id for the process for which the binder interface is to be frozen // enable: freeze (true) or unfreeze (false) // timeout_ms: maximum time this function is allowed to block the caller waiting for pending // binder transactions to be processed. // // returns: 0 in case of success, a value < 0 in case of error static status_t freeze(pid_t pid, bool enabled, uint32_t timeout_ms); // Provide information about the state of a frozen process static status_t getProcessFreezeInfo(pid_t pid, bool *sync_received, bool *async_received); // TODO: Remove the above legacy duplicated function in next version #ifndef __ANDROID_VNDK__ static status_t getProcessFreezeInfo(pid_t pid, uint32_t *sync_received, uint32_t *async_received); #endif sp process(); status_t clearLastError(); /** * Returns the PID of the process which has made the current binder * call. If not in a binder call, this will return getpid. If the * call is oneway, this will return 0. */ pid_t getCallingPid() const; /** * Returns the SELinux security identifier of the process which has * made the current binder call. If not in a binder call this will * return nullptr. If this isn't requested with * Binder::setRequestingSid, it will also return nullptr. * * This can't be restored once it's cleared, and it does not return the * context of the current process when not in a binder call. */ const char* getCallingSid() const; /** * Returns the UID of the process which has made the current binder * call. If not in a binder call, this will return 0. */ uid_t getCallingUid() const; void setStrictModePolicy(int32_t policy); int32_t getStrictModePolicy() const; // See Binder#setCallingWorkSourceUid in Binder.java. int64_t setCallingWorkSourceUid(uid_t uid); // Internal only. Use setCallingWorkSourceUid(uid) instead. int64_t setCallingWorkSourceUidWithoutPropagation(uid_t uid); // See Binder#getCallingWorkSourceUid in Binder.java. uid_t getCallingWorkSourceUid() const; // See Binder#clearCallingWorkSource in Binder.java. int64_t clearCallingWorkSource(); // See Binder#restoreCallingWorkSource in Binder.java. void restoreCallingWorkSource(int64_t token); void clearPropagateWorkSource(); bool shouldPropagateWorkSource() const; void setLastTransactionBinderFlags(int32_t flags); int32_t getLastTransactionBinderFlags() const; void setCallRestriction(CallRestriction restriction); CallRestriction getCallRestriction() const; int64_t clearCallingIdentity(); // Restores PID/UID (not SID) void restoreCallingIdentity(int64_t token); status_t setupPolling(int* fd); status_t handlePolledCommands(); void flushCommands(); bool flushIfNeeded(); void joinThreadPool(bool isMain = true); // Stop the local process. void stopProcess(bool immediate = true); status_t transact(int32_t handle, uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags); void incStrongHandle(int32_t handle, BpBinder *proxy); void decStrongHandle(int32_t handle); void incWeakHandle(int32_t handle, BpBinder *proxy); void decWeakHandle(int32_t handle); status_t attemptIncStrongHandle(int32_t handle); static void expungeHandle(int32_t handle, IBinder* binder); status_t requestDeathNotification( int32_t handle, BpBinder* proxy); status_t clearDeathNotification( int32_t handle, BpBinder* proxy); static void shutdown(); // Call this to disable switching threads to background scheduling when // receiving incoming IPC calls. This is specifically here for the // Android system process, since it expects to have background apps calling // in to it but doesn't want to acquire locks in its services while in // the background. static void disableBackgroundScheduling(bool disable); bool backgroundSchedulingDisabled(); // Call blocks until the number of executing binder threads is less than // the maximum number of binder threads threads allowed for this process. void blockUntilThreadAvailable(); // Service manager registration void setTheContextObject(const sp& obj); // WARNING: DO NOT USE THIS API // // Returns a pointer to the stack from the last time a transaction // was initiated by the kernel. Used to compare when making nested // calls between multiple different transports. const void* getServingStackPointer() const; // The work source represents the UID of the process we should attribute the transaction // to. We use -1 to specify that the work source was not set using #setWorkSource. // // This constant needs to be kept in sync with Binder.UNSET_WORKSOURCE from the Java // side. static const int32_t kUnsetWorkSource = -1; private: IPCThreadState(); ~IPCThreadState(); status_t sendReply(const Parcel& reply, uint32_t flags); status_t waitForResponse(Parcel *reply, status_t *acquireResult=nullptr); status_t talkWithDriver(bool doReceive=true); status_t writeTransactionData(int32_t cmd, uint32_t binderFlags, int32_t handle, uint32_t code, const Parcel& data, status_t* statusBuffer); status_t getAndExecuteCommand(); status_t executeCommand(int32_t command); void processPendingDerefs(); void processPostWriteDerefs(); void clearCaller(); static void threadDestructor(void *st); static void freeBuffer(Parcel* parcel, const uint8_t* data, size_t dataSize, const binder_size_t* objects, size_t objectsSize); const sp mProcess; Vector mPendingStrongDerefs; Vector mPendingWeakDerefs; Vector mPostWriteStrongDerefs; Vector mPostWriteWeakDerefs; Parcel mIn; Parcel mOut; status_t mLastError; const void* mServingStackPointer; pid_t mCallingPid; const char* mCallingSid; uid_t mCallingUid; // The UID of the process who is responsible for this transaction. // This is used for resource attribution. int32_t mWorkSource; // Whether the work source should be propagated. bool mPropagateWorkSource; bool mIsLooper; bool mIsFlushing; int32_t mStrictModePolicy; int32_t mLastTransactionBinderFlags; CallRestriction mCallRestriction; }; } // namespace android // ---------------------------------------------------------------------------