servicemanager: expose updatable-via-apex

Service manager is already reading VINTF, so processes that need this
information can access this information w/o needing more permissions.

Bug: 185832616
Test: two added tests + manually specifying updatable-via-apex on a
    service and checking the result
Change-Id: Id86a72d49466048a3e2173e40526981abb6f3123
diff --git a/cmds/dumpsys/tests/dumpsys_test.cpp b/cmds/dumpsys/tests/dumpsys_test.cpp
index 67a77f6..0ad2564 100644
--- a/cmds/dumpsys/tests/dumpsys_test.cpp
+++ b/cmds/dumpsys/tests/dumpsys_test.cpp
@@ -56,6 +56,7 @@
     MOCK_METHOD1(waitForService, sp<IBinder>(const String16&));
     MOCK_METHOD1(isDeclared, bool(const String16&));
     MOCK_METHOD1(getDeclaredInstances, Vector<String16>(const String16&));
+    MOCK_METHOD1(updatableViaApex, std::optional<String16>(const String16&));
   protected:
     MOCK_METHOD0(onAsBinder, IBinder*());
 };
diff --git a/cmds/servicemanager/ServiceManager.cpp b/cmds/servicemanager/ServiceManager.cpp
index 2f55249..b429fb3 100644
--- a/cmds/servicemanager/ServiceManager.cpp
+++ b/cmds/servicemanager/ServiceManager.cpp
@@ -58,22 +58,34 @@
     return false;
 }
 
-static bool isVintfDeclared(const std::string& name) {
-    size_t firstSlash = name.find('/');
-    size_t lastDot = name.rfind('.', firstSlash);
-    if (firstSlash == std::string::npos || lastDot == std::string::npos) {
-        LOG(ERROR) << "VINTF HALs require names in the format type/instance (e.g. "
-                   << "some.package.foo.IFoo/default) but got: " << name;
-        return false;
-    }
-    const std::string package = name.substr(0, lastDot);
-    const std::string iface = name.substr(lastDot+1, firstSlash-lastDot-1);
-    const std::string instance = name.substr(firstSlash+1);
+struct AidlName {
+    std::string package;
+    std::string iface;
+    std::string instance;
 
-    bool found = forEachManifest([&] (const ManifestWithDescription& mwd) {
-        if (mwd.manifest->hasAidlInstance(package, iface, instance)) {
+    static bool fill(const std::string& name, AidlName* aname) {
+        size_t firstSlash = name.find('/');
+        size_t lastDot = name.rfind('.', firstSlash);
+        if (firstSlash == std::string::npos || lastDot == std::string::npos) {
+            LOG(ERROR) << "VINTF HALs require names in the format type/instance (e.g. "
+                       << "some.package.foo.IFoo/default) but got: " << name;
+            return false;
+        }
+        aname->package = name.substr(0, lastDot);
+        aname->iface = name.substr(lastDot + 1, firstSlash - lastDot - 1);
+        aname->instance = name.substr(firstSlash + 1);
+        return true;
+    }
+};
+
+static bool isVintfDeclared(const std::string& name) {
+    AidlName aname;
+    if (!AidlName::fill(name, &aname)) return false;
+
+    bool found = forEachManifest([&](const ManifestWithDescription& mwd) {
+        if (mwd.manifest->hasAidlInstance(aname.package, aname.iface, aname.instance)) {
             LOG(INFO) << "Found " << name << " in " << mwd.description << " VINTF manifest.";
-            return true;
+            return true; // break
         }
         return false;  // continue
     });
@@ -81,13 +93,34 @@
     if (!found) {
         // Although it is tested, explicitly rebuilding qualified name, in case it
         // becomes something unexpected.
-        LOG(ERROR) << "Could not find " << package << "." << iface << "/" << instance
-                   << " in the VINTF manifest.";
+        LOG(ERROR) << "Could not find " << aname.package << "." << aname.iface << "/"
+                   << aname.instance << " in the VINTF manifest.";
     }
 
     return found;
 }
 
+static std::optional<std::string> getVintfUpdatableApex(const std::string& name) {
+    AidlName aname;
+    if (!AidlName::fill(name, &aname)) return std::nullopt;
+
+    std::optional<std::string> updatableViaApex;
+
+    forEachManifest([&](const ManifestWithDescription& mwd) {
+        mwd.manifest->forEachInstance([&](const auto& manifestInstance) {
+            if (manifestInstance.format() != vintf::HalFormat::AIDL) return true;
+            if (manifestInstance.package() != aname.package) return true;
+            if (manifestInstance.interface() != aname.iface) return true;
+            if (manifestInstance.instance() != aname.instance) return true;
+            updatableViaApex = manifestInstance.updatableViaApex();
+            return false; // break (libvintf uses opposite convention)
+        });
+        return false; // continue
+    });
+
+    return updatableViaApex;
+}
+
 static std::vector<std::string> getVintfInstances(const std::string& interface) {
     size_t lastDot = interface.rfind('.');
     if (lastDot == std::string::npos) {
@@ -388,6 +421,22 @@
     return Status::ok();
 }
 
+Status ServiceManager::updatableViaApex(const std::string& name,
+                                        std::optional<std::string>* outReturn) {
+    auto ctx = mAccess->getCallingContext();
+
+    if (!mAccess->canFind(ctx, name)) {
+        return Status::fromExceptionCode(Status::EX_SECURITY);
+    }
+
+    *outReturn = std::nullopt;
+
+#ifndef VENDORSERVICEMANAGER
+    *outReturn = getVintfUpdatableApex(name);
+#endif
+    return Status::ok();
+}
+
 void ServiceManager::removeRegistrationCallback(const wp<IBinder>& who,
                                     ServiceCallbackMap::iterator* it,
                                     bool* found) {
diff --git a/cmds/servicemanager/ServiceManager.h b/cmds/servicemanager/ServiceManager.h
index c089115..4f23c21 100644
--- a/cmds/servicemanager/ServiceManager.h
+++ b/cmds/servicemanager/ServiceManager.h
@@ -46,6 +46,8 @@
 
     binder::Status isDeclared(const std::string& name, bool* outReturn) override;
     binder::Status getDeclaredInstances(const std::string& interface, std::vector<std::string>* outReturn) override;
+    binder::Status updatableViaApex(const std::string& name,
+                                    std::optional<std::string>* outReturn) override;
     binder::Status registerClientCallback(const std::string& name, const sp<IBinder>& service,
                                           const sp<IClientCallback>& cb) override;
     binder::Status tryUnregisterService(const std::string& name, const sp<IBinder>& binder) override;
diff --git a/libs/binder/IServiceManager.cpp b/libs/binder/IServiceManager.cpp
index 61f4581..f684cf6 100644
--- a/libs/binder/IServiceManager.cpp
+++ b/libs/binder/IServiceManager.cpp
@@ -75,6 +75,7 @@
     sp<IBinder> waitForService(const String16& name16) override;
     bool isDeclared(const String16& name) override;
     Vector<String16> getDeclaredInstances(const String16& interface) override;
+    std::optional<String16> updatableViaApex(const String16& name) override;
 
     // for legacy ABI
     const String16& getInterfaceDescriptor() const override {
@@ -388,4 +389,12 @@
     return res;
 }
 
+std::optional<String16> ServiceManagerShim::updatableViaApex(const String16& name) {
+    std::optional<std::string> declared;
+    if (!mTheRealServiceManager->updatableViaApex(String8(name).c_str(), &declared).isOk()) {
+        return std::nullopt;
+    }
+    return declared ? std::optional<String16>(String16(declared.value().c_str())) : std::nullopt;
+}
+
 } // namespace android
diff --git a/libs/binder/aidl/android/os/IServiceManager.aidl b/libs/binder/aidl/android/os/IServiceManager.aidl
index 2fabf94..75c4092 100644
--- a/libs/binder/aidl/android/os/IServiceManager.aidl
+++ b/libs/binder/aidl/android/os/IServiceManager.aidl
@@ -108,6 +108,11 @@
     @utf8InCpp String[] getDeclaredInstances(@utf8InCpp String iface);
 
     /**
+     * If updatable-via-apex, returns the APEX via which this is updated.
+     */
+    @nullable @utf8InCpp String updatableViaApex(@utf8InCpp String name);
+
+    /**
      * Request a callback when the number of clients of the service changes.
      * Used by LazyServiceRegistrar to dynamically stop services that have no clients.
      */
diff --git a/libs/binder/include/binder/IServiceManager.h b/libs/binder/include/binder/IServiceManager.h
index 5f0d056..3dbe2c4 100644
--- a/libs/binder/include/binder/IServiceManager.h
+++ b/libs/binder/include/binder/IServiceManager.h
@@ -20,6 +20,8 @@
 #include <utils/Vector.h>
 #include <utils/String16.h>
 
+#include <optional>
+
 namespace android {
 
 // ----------------------------------------------------------------------
@@ -99,6 +101,12 @@
      * Get all instances of a service as declared in the VINTF manifest
      */
     virtual Vector<String16> getDeclaredInstances(const String16& interface) = 0;
+
+    /**
+     * If this instance is updatable via an APEX, returns the APEX with which
+     * this can be updated.
+     */
+    virtual std::optional<String16> updatableViaApex(const String16& name) = 0;
 };
 
 sp<IServiceManager> defaultServiceManager();
diff --git a/libs/binder/ndk/include_platform/android/binder_manager.h b/libs/binder/ndk/include_platform/android/binder_manager.h
index 5516914..a90b4aa 100644
--- a/libs/binder/ndk/include_platform/android/binder_manager.h
+++ b/libs/binder/ndk/include_platform/android/binder_manager.h
@@ -124,6 +124,15 @@
         __INTRODUCED_IN(31);
 
 /**
+ * Check if a service is updatable via an APEX module.
+ *
+ * \param instance identifier of the service
+ *
+ * \return whether the interface is updatable via APEX
+ */
+bool AServiceManager_isUpdatableViaApex(const char* instance) __INTRODUCED_IN(31);
+
+/**
  * Prevent lazy services without client from shutting down their process
  *
  * \param persist 'true' if the process should not exit.
diff --git a/libs/binder/ndk/libbinder_ndk.map.txt b/libs/binder/ndk/libbinder_ndk.map.txt
index 67c85b6..7d4b82e 100644
--- a/libs/binder/ndk/libbinder_ndk.map.txt
+++ b/libs/binder/ndk/libbinder_ndk.map.txt
@@ -118,14 +118,15 @@
     AIBinder_getCallingSid; # apex
     AIBinder_setRequestingSid; # apex
     AParcel_markSensitive; # llndk
-    AServiceManager_isDeclared; # apex llndk
     AServiceManager_forEachDeclaredInstance; # apex llndk
-    AServiceManager_registerLazyService; # llndk
-    AServiceManager_waitForService; # apex llndk
     AServiceManager_forceLazyServicesPersist; # llndk
+    AServiceManager_isDeclared; # apex llndk
+    AServiceManager_isUpdatableViaApex; # apex
+    AServiceManager_reRegister; # llndk
+    AServiceManager_registerLazyService; # llndk
     AServiceManager_setActiveServicesCallback; # llndk
     AServiceManager_tryUnregister; # llndk
-    AServiceManager_reRegister; # llndk
+    AServiceManager_waitForService; # apex llndk
 
     AIBinder_forceDowngradeToSystemStability; # apex
     AIBinder_forceDowngradeToVendorStability; # llndk
diff --git a/libs/binder/ndk/service_manager.cpp b/libs/binder/ndk/service_manager.cpp
index 1ccd0d2..7649a26 100644
--- a/libs/binder/ndk/service_manager.cpp
+++ b/libs/binder/ndk/service_manager.cpp
@@ -105,6 +105,14 @@
         callback(String8(instance).c_str(), context);
     }
 }
+bool AServiceManager_isUpdatableViaApex(const char* instance) {
+    if (instance == nullptr) {
+        return false;
+    }
+
+    sp<IServiceManager> sm = defaultServiceManager();
+    return sm->updatableViaApex(String16(instance)) != std::nullopt;
+}
 void AServiceManager_forceLazyServicesPersist(bool persist) {
     auto serviceRegistrar = android::binder::LazyServiceRegistrar::getInstance();
     serviceRegistrar.forcePersist(persist);
diff --git a/libs/binder/ndk/tests/libbinder_ndk_unit_test.cpp b/libs/binder/ndk/tests/libbinder_ndk_unit_test.cpp
index 496a915..1c43948 100644
--- a/libs/binder/ndk/tests/libbinder_ndk_unit_test.cpp
+++ b/libs/binder/ndk/tests/libbinder_ndk_unit_test.cpp
@@ -280,6 +280,11 @@
     EXPECT_EQ(STATUS_OK, AIBinder_ping(binder.get()));
 }
 
+TEST(NdkBinder, IsUpdatable) {
+    bool isUpdatable = AServiceManager_isUpdatableViaApex("android.hardware.light.ILights/default");
+    EXPECT_EQ(isUpdatable, false);
+}
+
 // This is too slow
 TEST(NdkBinder, CheckLazyServiceShutDown) {
     ndk::SpAIBinder binder(AServiceManager_waitForService(kLazyBinderNdkUnitTestService));
diff --git a/libs/binder/tests/binderStabilityTest.cpp b/libs/binder/tests/binderStabilityTest.cpp
index cb309bd..2ce13df 100644
--- a/libs/binder/tests/binderStabilityTest.cpp
+++ b/libs/binder/tests/binderStabilityTest.cpp
@@ -192,6 +192,8 @@
         EXPECT_EQ(Status::EX_ILLEGAL_ARGUMENT,
             android::defaultServiceManager()->addService(String16("."), vintfServer)) << instance8;
         EXPECT_FALSE(android::defaultServiceManager()->isDeclared(instance)) << instance8;
+        EXPECT_EQ(std::nullopt, android::defaultServiceManager()->updatableViaApex(instance))
+                << instance8;
     }
 }
 
diff --git a/libs/fakeservicemanager/ServiceManager.cpp b/libs/fakeservicemanager/ServiceManager.cpp
index 4ecbe53..761e45c 100644
--- a/libs/fakeservicemanager/ServiceManager.cpp
+++ b/libs/fakeservicemanager/ServiceManager.cpp
@@ -73,4 +73,9 @@
     return out;
 }
 
+std::optional<String16> ServiceManager::updatableViaApex(const String16& name) {
+    (void)name;
+    return std::nullopt;
+}
+
 }  // namespace android
diff --git a/libs/fakeservicemanager/ServiceManager.h b/libs/fakeservicemanager/ServiceManager.h
index 4ef47fb..e26c21b 100644
--- a/libs/fakeservicemanager/ServiceManager.h
+++ b/libs/fakeservicemanager/ServiceManager.h
@@ -19,6 +19,7 @@
 #include <binder/IServiceManager.h>
 
 #include <map>
+#include <optional>
 
 namespace android {
 
@@ -48,6 +49,8 @@
 
     Vector<String16> getDeclaredInstances(const String16& iface) override;
 
+    std::optional<String16> updatableViaApex(const String16& name) override;
+
 private:
     std::map<String16, sp<IBinder>> mNameToService;
 };