Merge "libbinder: allow stability downgrade" am: 7f284f9697 am: 54d423cde0 (c8b582fc) · Commits · e / os / android_frameworks_native-old

libs/binder/Stability.cpp

+30 −7

Original line number	Original line	Diff line number	Diff line
	@@ -38,6 +38,18 @@ Stability::Category Stability::Category::currentFromLevel(Level level) {
	};		};
	}		}

			void Stability::forceDowngradeCompilationUnit(const sp<IBinder>& binder) {
			// Downgrading a remote binder would require also copying the version from
			// the binder sent here. In practice though, we don't need to downgrade the
			// stability of a remote binder, since this would as an effect only restrict
			// what we can do to it.
			LOG_ALWAYS_FATAL_IF(!binder \|\| !binder->localBinder(), "Can only downgrade local binder");

			auto stability = Category::currentFromLevel(getLocalLevel());
			status_t result = setRepr(binder.get(), stability.repr(), REPR_LOG \| REPR_ALLOW_DOWNGRADE);
			LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");
			}

	std::string Stability::Category::debugString() {		std::string Stability::Category::debugString() {
	return levelString(level) + " wire protocol version "		return levelString(level) + " wire protocol version "
	+ std::to_string(version);		+ std::to_string(version);
	@@ -45,13 +57,13 @@ std::string Stability::Category::debugString() {

	void Stability::markCompilationUnit(IBinder* binder) {		void Stability::markCompilationUnit(IBinder* binder) {
	auto stability = Category::currentFromLevel(getLocalLevel());		auto stability = Category::currentFromLevel(getLocalLevel());
	status_t result = setRepr(binder, stability.repr(), true /log/);		status_t result = setRepr(binder, stability.repr(), REPR_LOG);
	LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");		LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");
	}		}

	void Stability::markVintf(IBinder* binder) {		void Stability::markVintf(IBinder* binder) {
	auto stability = Category::currentFromLevel(Level::VINTF);		auto stability = Category::currentFromLevel(Level::VINTF);
	status_t result = setRepr(binder, stability.repr(), true /log/);		status_t result = setRepr(binder, stability.repr(), REPR_LOG);
	LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");		LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");
	}		}

	@@ -62,7 +74,7 @@ void Stability::debugLogStability(const std::string& tag, const sp<IBinder>& bin

	void Stability::markVndk(IBinder* binder) {		void Stability::markVndk(IBinder* binder) {
	auto stability = Category::currentFromLevel(Level::VENDOR);		auto stability = Category::currentFromLevel(Level::VENDOR);
	status_t result = setRepr(binder, stability.repr(), true /log/);		status_t result = setRepr(binder, stability.repr(), REPR_LOG);
	LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");		LOG_ALWAYS_FATAL_IF(result != OK, "Should only mark known object.");
	}		}

	@@ -72,7 +84,7 @@ bool Stability::requiresVintfDeclaration(const sp<IBinder>& binder) {

	void Stability::tryMarkCompilationUnit(IBinder* binder) {		void Stability::tryMarkCompilationUnit(IBinder* binder) {
	auto stability = Category::currentFromLevel(getLocalLevel());		auto stability = Category::currentFromLevel(getLocalLevel());
	(void) setRepr(binder, stability.repr(), false /log/);		(void) setRepr(binder, stability.repr(), REPR_NONE);
	}		}

	Stability::Level Stability::getLocalLevel() {		Stability::Level Stability::getLocalLevel() {
	@@ -94,7 +106,10 @@ Stability::Level Stability::getLocalLevel() {
	#endif		#endif
	}		}

	status_t Stability::setRepr(IBinder* binder, int32_t representation, bool log) {		status_t Stability::setRepr(IBinder* binder, int32_t representation, uint32_t flags) {
			bool log = flags & REPR_LOG;
			bool allowDowngrade = flags & REPR_ALLOW_DOWNGRADE;

	auto current = getCategory(binder);		auto current = getCategory(binder);
	auto setting = Category::fromRepr(representation);		auto setting = Category::fromRepr(representation);

	@@ -129,7 +144,11 @@ status_t Stability::setRepr(IBinder* binder, int32_t representation, bool log) {
	return BAD_TYPE;		return BAD_TYPE;
	}		}

	if (current.repr() != 0 && current != setting) {		if (current == setting) return OK;

			bool hasAlreadyBeenSet = current.repr() != 0;
			bool isAllowedDowngrade = allowDowngrade && check(current, setting.level);
			if (hasAlreadyBeenSet && !isAllowedDowngrade) {
	if (log) {		if (log) {
	ALOGE("Interface being set with %s but it is already marked as %s",		ALOGE("Interface being set with %s but it is already marked as %s",
	setting.debugString().c_str(),		setting.debugString().c_str(),
	@@ -138,7 +157,11 @@ status_t Stability::setRepr(IBinder* binder, int32_t representation, bool log) {
	return BAD_TYPE;		return BAD_TYPE;
	}		}

	if (current == setting) return OK;		if (isAllowedDowngrade) {
			ALOGI("Interface set with %s downgraded to %s stability",
			current.debugString().c_str(),
			setting.debugString().c_str());
			}

	BBinder* local = binder->localBinder();		BBinder* local = binder->localBinder();
	if (local != nullptr) {		if (local != nullptr) {

libs/binder/include/binder/Stability.h

+15 −3

Original line number	Original line	Diff line number	Diff line
	@@ -49,10 +49,17 @@ namespace internal {
	// that it knows how to process. The summary of stability of a binder is		// that it knows how to process. The summary of stability of a binder is
	// represented by a Stability::Category object.		// represented by a Stability::Category object.

	// WARNING: These APIs are only ever expected to be called by auto-generated code.
	// Instead of calling them, you should set the stability of a .aidl interface
	class Stability final {		class Stability final {
	public:		public:
			// Given a binder interface at a certain stability, there may be some
			// requirements associated with that higher stability level. For instance, a
			// VINTF stability binder is required to be in the VINTF manifest. This API
			// can be called to use that same interface within a partition.
			static void forceDowngradeCompilationUnit(const sp<IBinder>& binder);

			// WARNING: Below APIs are only ever expected to be called by auto-generated code.
			// Instead of calling them, you should set the stability of a .aidl interface

	// WARNING: This is only ever expected to be called by auto-generated code. You likely want to		// WARNING: This is only ever expected to be called by auto-generated code. You likely want to
	// change or modify the stability class of the interface you are using.		// change or modify the stability class of the interface you are using.
	// This must be called as soon as the binder in question is constructed. No thread safety		// This must be called as soon as the binder in question is constructed. No thread safety
	@@ -139,9 +146,14 @@ private:
	// returns the stability according to how this was built		// returns the stability according to how this was built
	static Level getLocalLevel();		static Level getLocalLevel();

			enum {
			REPR_NONE = 0,
			REPR_LOG = 1,
			REPR_ALLOW_DOWNGRADE = 2,
			};
	// applies stability to binder if stability level is known		// applies stability to binder if stability level is known
	__attribute__((warn_unused_result))		__attribute__((warn_unused_result))
	static status_t setRepr(IBinder* binder, int32_t representation, bool log);		static status_t setRepr(IBinder* binder, int32_t representation, uint32_t flags);

	// get stability information as encoded on the wire		// get stability information as encoded on the wire
	static Category getCategory(IBinder* binder);		static Category getCategory(IBinder* binder);

libs/binder/tests/binderStabilityTest.cpp

+11 −0

Original line number	Original line	Diff line number	Diff line
	@@ -131,6 +131,17 @@ TEST(BinderStability, OnlyVintfStabilityBinderNeedsVintfDeclaration) {
	EXPECT_TRUE(Stability::requiresVintfDeclaration(BadStableBinder::vintf()));		EXPECT_TRUE(Stability::requiresVintfDeclaration(BadStableBinder::vintf()));
	}		}

			TEST(BinderStability, ForceDowngradeStability) {
			sp<IBinder> someBinder = BadStableBinder::vintf();

			EXPECT_TRUE(Stability::requiresVintfDeclaration(someBinder));

			// silly to do this after already using the binder, but it's for the test
			Stability::forceDowngradeCompilationUnit(someBinder);

			EXPECT_FALSE(Stability::requiresVintfDeclaration(someBinder));
			}

	TEST(BinderStability, VintfStabilityServerMustBeDeclaredInManifest) {		TEST(BinderStability, VintfStabilityServerMustBeDeclaredInManifest) {
	sp<IBinder> vintfServer = BadStableBinder::vintf();		sp<IBinder> vintfServer = BadStableBinder::vintf();