Merge "transcoding: trust MediaProvider to set uid for jobs" (f1065779) · Commits · e / os / android_frameworks_av

media/libmediatranscoding/TranscodingClientManager.cpp

+33 −17

Original line number	Diff line number	Diff line
		@@ -23,12 +23,16 @@
		#include <inttypes.h>
		#include <media/TranscodingClientManager.h>
		#include <media/TranscodingRequest.h>
		#include <media/TranscodingUidPolicy.h>
		#include <private/android_filesystem_config.h>
		#include <utils/Log.h>
		#include <utils/String16.h>
		namespace android {

		static_assert(sizeof(ClientIdType) == sizeof(void*), "ClientIdType should be pointer-sized");

		static constexpr const char* MEDIA_PROVIDER_PKG_NAME = "com.google.android.providers.media.module";

		using ::aidl::android::media::BnTranscodingClient;
		using ::aidl::android::media::IMediaTranscodingService; // For service error codes
		using ::aidl::android::media::TranscodingJobParcel;
		@@ -51,20 +55,6 @@ std::map<ClientIdType, std::shared_ptr<TranscodingClientManager::ClientImpl>>
		errorCode, \
		String8::format("%s:%d: " errorString, __FUNCTION__, __LINE__, ##__VA_ARGS__))

		// Can MediaTranscoding service trust the caller based on the calling UID?
		// TODO(hkuang): Add MediaProvider's UID.
		static bool isTrustedCallingUid(uid_t uid) {
		switch (uid) {
		case AID_ROOT: // root user
		case AID_SYSTEM:
		case AID_SHELL:
		case AID_MEDIA: // mediaserver
		return true;
		default:
		return false;
		}
		}

		/**
		* ClientImpl implements a single client and contains all its information.
		*/
		@@ -143,7 +133,7 @@ Status TranscodingClientManager::ClientImpl::submitRequest(
		in_clientUid = callingUid;
		} else if (in_clientUid < 0) {
		return Status::ok();
		} else if (in_clientUid != callingUid && !isTrustedCallingUid(callingUid)) {
		} else if (in_clientUid != callingUid && !owner->isTrustedCallingUid(callingUid)) {
		ALOGE("MediaTranscodingService::registerClient rejected (clientPid %d, clientUid %d) "
		"(don't trust callingUid %d)",
		in_clientPid, in_clientUid, callingUid);
		@@ -160,7 +150,7 @@ Status TranscodingClientManager::ClientImpl::submitRequest(
		in_clientPid = callingPid;
		} else if (in_clientPid < 0) {
		return Status::ok();
		} else if (in_clientPid != callingPid && !isTrustedCallingUid(callingUid)) {
		} else if (in_clientPid != callingPid && !owner->isTrustedCallingUid(callingUid)) {
		ALOGE("MediaTranscodingService::registerClient rejected (clientPid %d, clientUid %d) "
		"(don't trust callingUid %d)",
		in_clientPid, in_clientUid, callingUid);
		@@ -267,8 +257,18 @@ void TranscodingClientManager::BinderDiedCallback(void* cookie) {

		TranscodingClientManager::TranscodingClientManager(
		const std::shared_ptr<SchedulerClientInterface>& scheduler)
		: mDeathRecipient(AIBinder_DeathRecipient_new(BinderDiedCallback)), mJobScheduler(scheduler) {
		: mDeathRecipient(AIBinder_DeathRecipient_new(BinderDiedCallback)),
		mJobScheduler(scheduler),
		mMediaProviderUid(-1) {
		ALOGD("TranscodingClientManager started");
		uid_t mpuid;
		if (TranscodingUidPolicy::getUidForPackage(String16(MEDIA_PROVIDER_PKG_NAME), mpuid) ==
		NO_ERROR) {
		ALOGI("Found MediaProvider uid: %d", mpuid);
		mMediaProviderUid = mpuid;
		} else {
		ALOGW("Couldn't get uid for MediaProvider.");
		}
		}

		TranscodingClientManager::~TranscodingClientManager() {
		@@ -299,6 +299,22 @@ void TranscodingClientManager::dumpAllClients(int fd, const Vector<String16>& ar
		write(fd, result.string(), result.size());
		}

		bool TranscodingClientManager::isTrustedCallingUid(uid_t uid) {
		if (uid > 0 && uid == mMediaProviderUid) {
		return true;
		}

		switch (uid) {
		case AID_ROOT: // root user
		case AID_SYSTEM:
		case AID_SHELL:
		case AID_MEDIA: // mediaserver
		return true;
		default:
		return false;
		}
		}

		status_t TranscodingClientManager::addClient(
		const std::shared_ptr<ITranscodingClientCallback>& callback, const std::string& clientName,
		const std::string& opPackageName, std::shared_ptr<ITranscodingClient>* outClient) {

media/libmediatranscoding/TranscodingUidPolicy.cpp

+15 −0

Original line number	Diff line number	Diff line
		@@ -24,7 +24,9 @@
		#include <android/content/pm/IPackageManagerNative.h>
		#include <binder/ActivityManager.h>
		#include <binder/IServiceManager.h>
		#include <binder/PermissionController.h>
		#include <cutils/misc.h> // FIRST_APPLICATION_UID
		#include <cutils/multiuser.h>
		#include <inttypes.h>
		#include <media/TranscodingUidPolicy.h>
		#include <utils/Log.h>
		@@ -133,6 +135,19 @@ bool TranscodingUidPolicy::getNamesForUids(const std::vector<int32_t>& uids,
		return true;
		}

		//static
		status_t TranscodingUidPolicy::getUidForPackage(String16 packageName, /inout/ uid_t& uid) {
		PermissionController pc;
		uid = pc.getPackageUid(packageName, 0);
		if (uid <= 0) {
		ALOGE("Unknown package: '%s'", String8(packageName).string());
		return BAD_VALUE;
		}

		uid = multiuser_get_uid(0 /userId/, uid);
		return NO_ERROR;
		}

		TranscodingUidPolicy::TranscodingUidPolicy()
		: mAm(std::make_shared<ActivityManager>()),
		mUidObserver(new UidObserver(this)),

media/libmediatranscoding/include/media/TranscodingClientManager.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -86,6 +86,9 @@ private:
		// Only allow MediaTranscodingService and unit tests to instantiate.
		TranscodingClientManager(const std::shared_ptr<SchedulerClientInterface>& scheduler);

		// Checks if a user is trusted (and allowed to submit jobs on behalf of other uids)
		bool isTrustedCallingUid(uid_t uid);

		/**
		* Removes an existing client from the manager.
		*
		@@ -106,6 +109,7 @@ private:
		::ndk::ScopedAIBinder_DeathRecipient mDeathRecipient;

		std::shared_ptr<SchedulerClientInterface> mJobScheduler;
		uid_t mMediaProviderUid;

		static std::atomic<ClientIdType> sCookieCounter;
		static std::mutex sCookie2ClientLock;

media/libmediatranscoding/include/media/TranscodingUidPolicy.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -50,6 +50,7 @@ public:
		// ~UidPolicyInterface

		static bool getNamesForUids(const std::vector<int32_t>& uids, std::vector<std::string>* names);
		static status_t getUidForPackage(String16 packageName, /inout/ uid_t& uid);

		private:
		void onUidStateChanged(uid_t uid, int32_t procState);