Merge "Add methods to read/update request headers" (b0e24871) · Commits · e / os / platform_frameworks_native

libs/binder/Parcel.cpp

+39 −0

Original line number	Diff line number	Diff line
		@@ -599,17 +599,53 @@ bool Parcel::hasFileDescriptors() const
		return mHasFds;
		}

		void Parcel::updateWorkSourceRequestHeaderPosition() const {
		// Only update the request headers once. We only want to point
		// to the first headers read/written.
		if (!mRequestHeaderPresent) {
		mWorkSourceRequestHeaderPosition = dataPosition();
		mRequestHeaderPresent = true;
		}
		}

		// Write RPC headers. (previously just the interface token)
		status_t Parcel::writeInterfaceToken(const String16& interface)
		{
		const IPCThreadState* threadState = IPCThreadState::self();
		writeInt32(threadState->getStrictModePolicy() \| STRICT_MODE_PENALTY_GATHER);
		updateWorkSourceRequestHeaderPosition();
		writeInt32(threadState->shouldPropagateWorkSource() ?
		threadState->getCallingWorkSourceUid() : IPCThreadState::kUnsetWorkSource);
		// currently the interface identification token is just its name as a string
		return writeString16(interface);
		}

		bool Parcel::replaceCallingWorkSourceUid(uid_t uid)
		{
		if (!mRequestHeaderPresent) {
		return false;
		}

		const size_t initialPosition = dataPosition();
		setDataPosition(mWorkSourceRequestHeaderPosition);
		status_t err = writeInt32(uid);
		setDataPosition(initialPosition);
		return err == NO_ERROR;
		}

		uid_t Parcel::readCallingWorkSourceUid()
		{
		if (!mRequestHeaderPresent) {
		return IPCThreadState::kUnsetWorkSource;
		}

		const size_t initialPosition = dataPosition();
		setDataPosition(mWorkSourceRequestHeaderPosition);
		uid_t uid = readInt32();
		setDataPosition(initialPosition);
		return uid;
		}

		bool Parcel::checkInterface(IBinder* binder) const
		{
		return enforceInterface(binder->getInterfaceDescriptor());
		@@ -634,6 +670,7 @@ bool Parcel::enforceInterface(const String16& interface,
		threadState->setStrictModePolicy(strictPolicy);
		}
		// WorkSource.
		updateWorkSourceRequestHeaderPosition();
		int32_t workSource = readInt32();
		threadState->setCallingWorkSourceUidWithoutPropagation(workSource);
		// Interface descriptor.
		@@ -2889,6 +2926,8 @@ void Parcel::initState()
		mAllowFds = true;
		mOwner = nullptr;
		mOpenAshmemSize = 0;
		mWorkSourceRequestHeaderPosition = 0;
		mRequestHeaderPresent = false;

		// racing multiple init leads only to multiple identical write
		if (gMaxFds == 0) {

libs/binder/include/binder/Parcel.h

+10 −0

Original line number	Diff line number	Diff line
		@@ -395,6 +395,12 @@ public:
		static size_t getGlobalAllocSize();
		static size_t getGlobalAllocCount();

		bool replaceCallingWorkSourceUid(uid_t uid);
		// Returns the work source provided by the caller. This can only be trusted for trusted calling
		// uid.
		uid_t readCallingWorkSourceUid();
		void readRequestHeaders() const;

		private:
		typedef void (release_func)(Parcel parcel,
		const uint8_t* data, size_t dataSize,
		@@ -429,6 +435,7 @@ private:
		void initState();
		void scanForFds() const;
		status_t validateReadData(size_t len) const;
		void updateWorkSourceRequestHeaderPosition() const;

		template<class T>
		status_t readAligned(T *pArg) const;
		@@ -477,6 +484,9 @@ private:
		mutable size_t mNextObjectHint;
		mutable bool mObjectsSorted;

		mutable bool mRequestHeaderPresent;
		mutable size_t mWorkSourceRequestHeaderPosition;

		mutable bool mFdsKnown;
		mutable bool mHasFds;
		bool mAllowFds;