Merge "Add libbinder_ndk systemapi support for injecting RPC binder accessors"... (55c73dd0) · Commits · e / os / android_frameworks_native

libs/binder/IServiceManager.cpp

+38 −6

Original line number	Diff line number	Diff line
		@@ -157,12 +157,21 @@ protected:

		class AccessorProvider {
		public:
		AccessorProvider(RpcAccessorProvider&& provider) : mProvider(std::move(provider)) {}
		sp<IBinder> provide(const String16& name) { return mProvider(name); }
		AccessorProvider(std::set<std::string>&& instances, RpcAccessorProvider&& provider)
		: mInstances(std::move(instances)), mProvider(std::move(provider)) {}
		sp<IBinder> provide(const String16& name) {
		if (mInstances.count(String8(name).c_str()) > 0) {
		return mProvider(name);
		} else {
		return nullptr;
		}
		}
		const std::set<std::string>& instances() { return mInstances; }

		private:
		AccessorProvider() = delete;

		std::set<std::string> mInstances;
		RpcAccessorProvider mProvider;
		};

		@@ -318,10 +327,32 @@ sp<IServiceManager> getServiceManagerShimFromAidlServiceManagerForTests(
		return sp<CppBackendShim>::make(sp<BackendUnifiedServiceManager>::make(sm));
		}

		std::weak_ptr<AccessorProvider> addAccessorProvider(RpcAccessorProvider&& providerCallback) {
		// gAccessorProvidersMutex must be locked already
		static bool isInstanceProvidedLocked(const std::string& instance) {
		return gAccessorProviders.end() !=
		std::find_if(gAccessorProviders.begin(), gAccessorProviders.end(),
		[&instance](const AccessorProviderEntry& entry) {
		return entry.mProvider->instances().count(instance) > 0;
		});
		}

		std::weak_ptr<AccessorProvider> addAccessorProvider(std::set<std::string>&& instances,
		RpcAccessorProvider&& providerCallback) {
		if (instances.empty()) {
		ALOGE("Set of instances is empty! Need a non empty set of instances to provide for.");
		return std::weak_ptr<AccessorProvider>();
		}
		std::lock_guard<std::mutex> lock(gAccessorProvidersMutex);
		for (const auto& instance : instances) {
		if (isInstanceProvidedLocked(instance)) {
		ALOGE("The instance %s is already provided for by a previously added "
		"RpcAccessorProvider.",
		instance.c_str());
		return std::weak_ptr<AccessorProvider>();
		}
		}
		std::shared_ptr<AccessorProvider> provider =
		std::make_shared<AccessorProvider>(std::move(providerCallback));
		std::make_shared<AccessorProvider>(std::move(instances), std::move(providerCallback));
		std::weak_ptr<AccessorProvider> receipt = provider;
		gAccessorProviders.push_back(AccessorProviderEntry(std::move(provider)));

		@@ -331,8 +362,9 @@ std::weak_ptr<AccessorProvider> addAccessorProvider(RpcAccessorProvider&& provid
		status_t removeAccessorProvider(std::weak_ptr<AccessorProvider> wProvider) {
		std::shared_ptr<AccessorProvider> provider = wProvider.lock();
		if (provider == nullptr) {
		ALOGE("The provider supplied to removeAccessorProvider has already been removed.");
		return NAME_NOT_FOUND;
		ALOGE("The provider supplied to removeAccessorProvider has already been removed or the "
		"argument to this function was nullptr.");
		return BAD_VALUE;
		}
		std::lock_guard<std::mutex> lock(gAccessorProvidersMutex);
		size_t sizeBefore = gAccessorProviders.size();

libs/binder/include/binder/IServiceManager.h

+20 −3

Original line number	Diff line number	Diff line
		@@ -24,6 +24,7 @@
		#include <utils/String16.h>
		#include <utils/Vector.h>
		#include <optional>
		#include <set>

		namespace android {

		@@ -224,20 +225,36 @@ LIBBINDER_EXPORTED bool checkPermission(const String16& permission, pid_t pid, u
		typedef std::function<status_t(const String16& name, sockaddr* outAddr, socklen_t addrSize)>
		RpcSocketAddressProvider;

		typedef std::function<sp<IBinder>(const String16& name)> RpcAccessorProvider;
		/**
		* This callback provides a way for clients to get access to remote services by
		* providing an Accessor object from libbinder that can connect to the remote
		* service over sockets.
		*
		* \param instance name of the service that the callback will provide an
		* Accessor for. The provided accessor will be used to set up a client
		* RPC connection in libbinder in order to return a binder for the
		* associated remote service.
		*
		* \return IBinder of the Accessor object that libbinder implements.
		* nullptr if the provider callback doesn't know how to reach the
		* service or doesn't want to provide access for any other reason.
		*/
		typedef std::function<sp<IBinder>(const String16& instance)> RpcAccessorProvider;

		class AccessorProvider;

		/**
		* Register an accessor provider for the service manager APIs.
		* Register a RpcAccessorProvider for the service manager APIs.
		*
		* \param instances that the RpcAccessorProvider knows about and can provide an
		* Accessor for.
		* \param provider callback that generates Accessors.
		*
		* \return A pointer used as a recept for the successful addition of the
		* AccessorProvider. This is needed to unregister it later.
		*/
		[[nodiscard]] LIBBINDER_EXPORTED std::weak_ptr<AccessorProvider> addAccessorProvider(
		RpcAccessorProvider&& providerCallback);
		std::set<std::string>&& instances, RpcAccessorProvider&& providerCallback);

		/**
		* Remove an accessor provider using the pointer provided by addAccessorProvider

libs/binder/ndk/Android.bp

+1 −0

Original line number	Diff line number	Diff line
		@@ -95,6 +95,7 @@ cc_library {
		"persistable_bundle.cpp",
		"process.cpp",
		"service_manager.cpp",
		"binder_rpc.cpp",
		],

		static_libs: [

libs/binder/ndk/binder_rpc.cpp

0 → 100644

+352 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) 2024 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.
		*/

		#include <android/binder_rpc.h>
		#include <arpa/inet.h>
		#include <binder/IServiceManager.h>
		#include <linux/vm_sockets.h>
		#include <netinet/in.h>
		#include <sys/socket.h>
		#include <sys/un.h>

		#include <variant>

		#include "ibinder_internal.h"
		#include "status_internal.h"

		using ::android::defaultServiceManager;
		using ::android::IBinder;
		using ::android::IServiceManager;
		using ::android::OK;
		using ::android::sp;
		using ::android::status_t;
		using ::android::String16;
		using ::android::String8;
		using ::android::binder::Status;

		#define LOG_ACCESSOR_DEBUG(...)
		// #define LOG_ACCESSOR_DEBUG(...) ALOGW(__VA_ARGS__)

		struct ABinderRpc_ConnectionInfo {
		std::variant<sockaddr_vm, sockaddr_un, sockaddr_in> addr;
		};

		struct ABinderRpc_Accessor final : public ::android::RefBase {
		static ABinderRpc_Accessor* make(const char* instance, const sp<IBinder>& binder) {
		LOG_ALWAYS_FATAL_IF(binder == nullptr, "ABinderRpc_Accessor requires a non-null binder");
		status_t status = android::validateAccessor(String16(instance), binder);
		if (status != OK) {
		ALOGE("The given binder is not a valid IAccessor for %s. Status: %s", instance,
		android::statusToString(status).c_str());
		return nullptr;
		}
		return new ABinderRpc_Accessor(binder);
		}

		sp<IBinder> asBinder() { return mAccessorBinder; }

		~ABinderRpc_Accessor() { LOG_ACCESSOR_DEBUG("ABinderRpc_Accessor dtor"); }

		private:
		ABinderRpc_Accessor(sp<IBinder> accessor) : mAccessorBinder(accessor) {}
		ABinderRpc_Accessor() = delete;
		sp<IBinder> mAccessorBinder;
		};

		struct ABinderRpc_AccessorProvider {
		public:
		static ABinderRpc_AccessorProvider* make(std::weak_ptr<android::AccessorProvider> cookie) {
		if (cookie.expired()) {
		ALOGE("Null AccessorProvider cookie from libbinder");
		return nullptr;
		}
		return new ABinderRpc_AccessorProvider(cookie);
		}
		std::weak_ptr<android::AccessorProvider> mProviderCookie;

		private:
		ABinderRpc_AccessorProvider() = delete;

		ABinderRpc_AccessorProvider(std::weak_ptr<android::AccessorProvider> provider)
		: mProviderCookie(provider) {}
		};

		struct OnDeleteProviderHolder {
		OnDeleteProviderHolder(void* data, ABinderRpc_AccessorProviderUserData_deleteCallback onDelete)
		: mData(data), mOnDelete(onDelete) {}
		~OnDeleteProviderHolder() {
		if (mOnDelete) {
		mOnDelete(mData);
		}
		}
		void* mData;
		ABinderRpc_AccessorProviderUserData_deleteCallback mOnDelete;
		// needs to be copyable for std::function, but we will never copy it
		OnDeleteProviderHolder(const OnDeleteProviderHolder&) {
		LOG_ALWAYS_FATAL("This object can't be copied!");
		}

		private:
		OnDeleteProviderHolder() = delete;
		};

		ABinderRpc_AccessorProvider* ABinderRpc_registerAccessorProvider(
		ABinderRpc_AccessorProvider_getAccessorCallback provider, const char** instances,
		size_t numInstances, void* data,
		ABinderRpc_AccessorProviderUserData_deleteCallback onDelete) {
		if (provider == nullptr) {
		ALOGE("Null provider passed to ABinderRpc_registerAccessorProvider");
		return nullptr;
		}
		if (data && onDelete == nullptr) {
		ALOGE("If a non-null data ptr is passed to ABinderRpc_registerAccessorProvider, then a "
		"ABinderRpc_AccessorProviderUserData_deleteCallback must alse be passed to delete "
		"the data object once the ABinderRpc_AccessorProvider is removed.");
		return nullptr;
		}
		if (numInstances == 0 \|\| instances == nullptr) {
		ALOGE("No instances passed to ABinderRpc_registerAccessorProvider. numInstances: %zu",
		numInstances);
		return nullptr;
		}
		std::set<std::string> instanceStrings;
		for (size_t i = 0; i < numInstances; i++) {
		instanceStrings.emplace(instances[i]);
		}
		// call the onDelete when the last reference of this goes away (when the
		// last reference to the generate std::function goes away).
		std::shared_ptr<OnDeleteProviderHolder> onDeleteHolder =
		std::make_shared<OnDeleteProviderHolder>(data, onDelete);
		android::RpcAccessorProvider generate = [provider,
		onDeleteHolder](const String16& name) -> sp<IBinder> {
		ABinderRpc_Accessor* accessor = provider(String8(name).c_str(), onDeleteHolder->mData);
		if (accessor == nullptr) {
		ALOGE("The supplied ABinderRpc_AccessorProvider_getAccessorCallback returned nullptr");
		return nullptr;
		}
		sp<IBinder> binder = accessor->asBinder();
		ABinderRpc_Accessor_delete(accessor);
		return binder;
		};

		std::weak_ptr<android::AccessorProvider> cookie =
		android::addAccessorProvider(std::move(instanceStrings), std::move(generate));
		return ABinderRpc_AccessorProvider::make(cookie);
		}

		void ABinderRpc_unregisterAccessorProvider(ABinderRpc_AccessorProvider* provider) {
		if (provider == nullptr) {
		LOG_ALWAYS_FATAL("Attempting to remove a null ABinderRpc_AccessorProvider");
		}

		status_t status = android::removeAccessorProvider(provider->mProviderCookie);
		// There shouldn't be a way to get here because the caller won't have a
		// ABinderRpc_AccessorProvider* without calling ABinderRpc_registerAccessorProvider
		LOG_ALWAYS_FATAL_IF(status == android::BAD_VALUE, "Provider (%p) is not valid. Status: %s",
		provider, android::statusToString(status).c_str());
		LOG_ALWAYS_FATAL_IF(status == android::NAME_NOT_FOUND,
		"Provider (%p) was already unregistered. Status: %s", provider,
		android::statusToString(status).c_str());
		LOG_ALWAYS_FATAL_IF(status != OK,
		"Unknown error when attempting to unregister ABinderRpc_AccessorProvider "
		"(%p). Status: %s",
		provider, android::statusToString(status).c_str());

		delete provider;
		}

		struct OnDeleteConnectionInfoHolder {
		OnDeleteConnectionInfoHolder(void* data,
		ABinderRpc_ConnectionInfoProviderUserData_delete onDelete)
		: mData(data), mOnDelete(onDelete) {}
		~OnDeleteConnectionInfoHolder() {
		if (mOnDelete) {
		mOnDelete(mData);
		}
		}
		void* mData;
		ABinderRpc_ConnectionInfoProviderUserData_delete mOnDelete;
		// needs to be copyable for std::function, but we will never copy it
		OnDeleteConnectionInfoHolder(const OnDeleteConnectionInfoHolder&) {
		LOG_ALWAYS_FATAL("This object can't be copied!");
		}

		private:
		OnDeleteConnectionInfoHolder() = delete;
		};

		ABinderRpc_Accessor* ABinderRpc_Accessor_new(
		const char* instance, ABinderRpc_ConnectionInfoProvider provider, void* data,
		ABinderRpc_ConnectionInfoProviderUserData_delete onDelete) {
		if (instance == nullptr) {
		ALOGE("Instance argument must be valid when calling ABinderRpc_Accessor_new");
		return nullptr;
		}
		if (data && onDelete == nullptr) {
		ALOGE("If a non-null data ptr is passed to ABinderRpc_Accessor_new, then a "
		"ABinderRpc_ConnectionInfoProviderUserData_delete callback must alse be passed to "
		"delete "
		"the data object once the ABinderRpc_Accessor is deleted.");
		return nullptr;
		}
		std::shared_ptr<OnDeleteConnectionInfoHolder> onDeleteHolder =
		std::make_shared<OnDeleteConnectionInfoHolder>(data, onDelete);
		if (provider == nullptr) {
		ALOGE("Can't create a new ABinderRpc_Accessor without a ABinderRpc_ConnectionInfoProvider "
		"and it is "
		"null");
		return nullptr;
		}
		android::RpcSocketAddressProvider generate = [provider, onDeleteHolder](
		const String16& name, sockaddr* outAddr,
		size_t addrLen) -> status_t {
		std::unique_ptr<ABinderRpc_ConnectionInfo> info(
		provider(String8(name).c_str(), onDeleteHolder->mData));
		if (info == nullptr) {
		ALOGE("The supplied ABinderRpc_ConnectionInfoProvider returned nullptr");
		return android::NAME_NOT_FOUND;
		}
		if (auto addr = std::get_if<sockaddr_vm>(&info->addr)) {
		LOG_ALWAYS_FATAL_IF(addr->svm_family != AF_VSOCK,
		"ABinderRpc_ConnectionInfo invalid family");
		if (addrLen < sizeof(sockaddr_vm)) {
		ALOGE("Provided outAddr is too small! Expecting %zu, got %zu", sizeof(sockaddr_vm),
		addrLen);
		return android::BAD_VALUE;
		}
		LOG_ACCESSOR_DEBUG(
		"Connection info provider found AF_VSOCK. family %d, port %d, cid %d",
		addr->svm_family, addr->svm_port, addr->svm_cid);
		reinterpret_cast<sockaddr_vm>(outAddr) = *addr;
		} else if (auto addr = std::get_if<sockaddr_un>(&info->addr)) {
		LOG_ALWAYS_FATAL_IF(addr->sun_family != AF_UNIX,
		"ABinderRpc_ConnectionInfo invalid family");
		if (addrLen < sizeof(sockaddr_un)) {
		ALOGE("Provided outAddr is too small! Expecting %zu, got %zu", sizeof(sockaddr_un),
		addrLen);
		return android::BAD_VALUE;
		}
		reinterpret_cast<sockaddr_un>(outAddr) = *addr;
		} else if (auto addr = std::get_if<sockaddr_in>(&info->addr)) {
		LOG_ALWAYS_FATAL_IF(addr->sin_family != AF_INET,
		"ABinderRpc_ConnectionInfo invalid family");
		if (addrLen < sizeof(sockaddr_in)) {
		ALOGE("Provided outAddr is too small! Expecting %zu, got %zu", sizeof(sockaddr_in),
		addrLen);
		return android::BAD_VALUE;
		}
		reinterpret_cast<sockaddr_in>(outAddr) = *addr;
		} else {
		LOG_ALWAYS_FATAL(
		"Unsupported address family type when trying to get ARpcConnection info. A "
		"new variant was added to the ABinderRpc_ConnectionInfo and this needs to be "
		"updated.");
		}
		return OK;
		};
		sp<IBinder> accessorBinder = android::createAccessor(String16(instance), std::move(generate));
		if (accessorBinder == nullptr) {
		ALOGE("service manager did not get us an accessor");
		return nullptr;
		}
		LOG_ACCESSOR_DEBUG("service manager found an accessor, so returning one now from _new");
		return ABinderRpc_Accessor::make(instance, accessorBinder);
		}

		void ABinderRpc_Accessor_delete(ABinderRpc_Accessor* accessor) {
		delete accessor;
		}

		AIBinder* ABinderRpc_Accessor_asBinder(ABinderRpc_Accessor* accessor) {
		if (!accessor) {
		ALOGE("ABinderRpc_Accessor argument is null.");
		return nullptr;
		}

		sp<IBinder> binder = accessor->asBinder();
		sp<AIBinder> aBinder = ABpBinder::lookupOrCreateFromBinder(binder);
		AIBinder* ptr = aBinder.get();
		if (ptr == nullptr) {
		LOG_ALWAYS_FATAL("Failed to lookupOrCreateFromBinder");
		}
		ptr->incStrong(nullptr);
		return ptr;
		}

		ABinderRpc_Accessor* ABinderRpc_Accessor_fromBinder(const char* instance, AIBinder* binder) {
		if (!binder) {
		ALOGE("binder argument is null");
		return nullptr;
		}
		sp<IBinder> accessorBinder = binder->getBinder();
		if (accessorBinder) {
		return ABinderRpc_Accessor::make(instance, accessorBinder);
		} else {
		ALOGE("Attempting to get an ABinderRpc_Accessor for %s but AIBinder::getBinder returned "
		"null",
		instance);
		return nullptr;
		}
		}

		ABinderRpc_ConnectionInfo* ABinderRpc_ConnectionInfo_new(const sockaddr* addr, socklen_t len) {
		if (addr == nullptr \|\| len < 0 \|\| static_cast<size_t>(len) < sizeof(sa_family_t)) {
		ALOGE("Invalid arguments in Arpc_Connection_new");
		return nullptr;
		}
		// socklen_t was int32_t on 32-bit and uint32_t on 64 bit.
		size_t socklen = len < 0 \|\| static_cast<uintmax_t>(len) > SIZE_MAX ? 0 : len;

		if (addr->sa_family == AF_VSOCK) {
		if (len != sizeof(sockaddr_vm)) {
		ALOGE("Incorrect size of %zu for AF_VSOCK sockaddr_vm. Expecting %zu", socklen,
		sizeof(sockaddr_vm));
		return nullptr;
		}
		sockaddr_vm vm = reinterpret_cast<const sockaddr_vm>(addr);
		LOG_ACCESSOR_DEBUG("Arpc_ConnectionInfo_new found AF_VSOCK. family %d, port %d, cid %d",
		vm.svm_family, vm.svm_port, vm.svm_cid);
		return new ABinderRpc_ConnectionInfo(vm);
		} else if (addr->sa_family == AF_UNIX) {
		if (len != sizeof(sockaddr_un)) {
		ALOGE("Incorrect size of %zu for AF_UNIX sockaddr_un. Expecting %zu", socklen,
		sizeof(sockaddr_un));
		return nullptr;
		}
		sockaddr_un un = reinterpret_cast<const sockaddr_un>(addr);
		LOG_ACCESSOR_DEBUG("Arpc_ConnectionInfo_new found AF_UNIX. family %d, path %s",
		un.sun_family, un.sun_path);
		return new ABinderRpc_ConnectionInfo(un);
		} else if (addr->sa_family == AF_INET) {
		if (len != sizeof(sockaddr_in)) {
		ALOGE("Incorrect size of %zu for AF_INET sockaddr_in. Expecting %zu", socklen,
		sizeof(sockaddr_in));
		return nullptr;
		}
		sockaddr_in in = reinterpret_cast<const sockaddr_in>(addr);
		LOG_ACCESSOR_DEBUG("Arpc_ConnectionInfo_new found AF_INET. family %d, address %s, port %d",
		in.sin_family, inet_ntoa(in.sin_addr), ntohs(in.sin_port));
		return new ABinderRpc_ConnectionInfo(in);
		}

		ALOGE("ARpc APIs only support AF_VSOCK right now but the supplied sockadder::sa_family is: %hu",
		addr->sa_family);
		return nullptr;
		}

		void ABinderRpc_ConnectionInfo_delete(ABinderRpc_ConnectionInfo* info) {
		delete info;
		}

libs/binder/ndk/include_platform/android/binder_rpc.h

0 → 100644

+261 −0

File added.

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