Flag guard the code related to the vendor modules feature

The feature is guarded by the RELEASE_AVF_ENABLE_VENDOR_MODULES flag. On
the virtmgr side the flag-guard check is done in the create_vm_internal
function. On the vm binary side the related flags (--vendor, --kernel)
are only enabled if the RELEASE_AVF_ENABLE_VENDOR_MODULES flag is
enabled.

Additionally the vendor modules related tests in MicrodroidTests now run
conditionally depending on the result of the
`isFeatureEnabled(FEATURE_VENDOR_MODULES)` call.

Bug: 298007909
Test: atest MicrodroidTests
Change-Id: I1467194c802720601a10d0a760a8f1d7ce134037
diff --git a/Android.bp b/Android.bp
index 1fae793..d1086ba 100644
--- a/Android.bp
+++ b/Android.bp
@@ -34,6 +34,7 @@
     config_namespace: "ANDROID",
     bool_variables: [
         "release_avf_enable_multi_tenant_microdroid_vm",
+        "release_avf_enable_vendor_modules",
     ],
     properties: [
         "cfgs",
@@ -46,5 +47,8 @@
         release_avf_enable_multi_tenant_microdroid_vm: {
             cfgs: ["payload_not_root"],
         },
+        release_avf_enable_vendor_modules: {
+            cfgs: ["vendor_modules"],
+        },
     },
 }
diff --git a/javalib/api/test-current.txt b/javalib/api/test-current.txt
index 51c2223..bedb267 100644
--- a/javalib/api/test-current.txt
+++ b/javalib/api/test-current.txt
@@ -13,13 +13,14 @@
 
   public static final class VirtualMachineConfig.Builder {
     method @NonNull @RequiresPermission(android.system.virtualmachine.VirtualMachine.USE_CUSTOM_VIRTUAL_MACHINE_PERMISSION) public android.system.virtualmachine.VirtualMachineConfig.Builder setPayloadConfigPath(@NonNull String);
-    method @NonNull @RequiresPermission(android.system.virtualmachine.VirtualMachine.USE_CUSTOM_VIRTUAL_MACHINE_PERMISSION) public android.system.virtualmachine.VirtualMachineConfig.Builder setVendorDiskImage(@NonNull java.io.File);
+    method @FlaggedApi("RELEASE_AVF_ENABLE_VENDOR_MODULES") @NonNull @RequiresPermission(android.system.virtualmachine.VirtualMachine.USE_CUSTOM_VIRTUAL_MACHINE_PERMISSION) public android.system.virtualmachine.VirtualMachineConfig.Builder setVendorDiskImage(@NonNull java.io.File);
     method @NonNull public android.system.virtualmachine.VirtualMachineConfig.Builder setVmConsoleInputSupported(boolean);
   }
 
   public class VirtualMachineManager {
     method @RequiresPermission(android.system.virtualmachine.VirtualMachine.MANAGE_VIRTUAL_MACHINE_PERMISSION) public boolean isFeatureEnabled(String) throws android.system.virtualmachine.VirtualMachineException;
     field public static final String FEATURE_PAYLOAD_NOT_ROOT = "com.android.kvm.PAYLOAD_NON_ROOT";
+    field public static final String FEATURE_VENDOR_MODULES = "com.android.kvm.VENDOR_MODULES";
   }
 
 }
diff --git a/javalib/src/android/system/virtualmachine/VirtualMachineConfig.java b/javalib/src/android/system/virtualmachine/VirtualMachineConfig.java
index b307854..cc8f65b 100644
--- a/javalib/src/android/system/virtualmachine/VirtualMachineConfig.java
+++ b/javalib/src/android/system/virtualmachine/VirtualMachineConfig.java
@@ -21,6 +21,7 @@
 
 import static java.util.Objects.requireNonNull;
 
+import android.annotation.FlaggedApi;
 import android.annotation.IntDef;
 import android.annotation.IntRange;
 import android.annotation.NonNull;
@@ -903,6 +904,7 @@
          */
         @TestApi
         @RequiresPermission(VirtualMachine.USE_CUSTOM_VIRTUAL_MACHINE_PERMISSION)
+        @FlaggedApi("RELEASE_AVF_ENABLE_VENDOR_MODULES")
         @NonNull
         public Builder setVendorDiskImage(@NonNull File vendorDiskImage) {
             mVendorDiskImage = vendorDiskImage;
diff --git a/javalib/src/android/system/virtualmachine/VirtualMachineManager.java b/javalib/src/android/system/virtualmachine/VirtualMachineManager.java
index c4096da..0a79553 100644
--- a/javalib/src/android/system/virtualmachine/VirtualMachineManager.java
+++ b/javalib/src/android/system/virtualmachine/VirtualMachineManager.java
@@ -107,7 +107,7 @@
     @Retention(RetentionPolicy.SOURCE)
     @StringDef(
             prefix = "FEATURE_",
-            value = {FEATURE_PAYLOAD_NOT_ROOT})
+            value = {FEATURE_PAYLOAD_NOT_ROOT, FEATURE_VENDOR_MODULES})
     public @interface Features {}
 
     /**
@@ -120,6 +120,15 @@
             IVirtualizationService.FEATURE_PAYLOAD_NON_ROOT;
 
     /**
+     * Feature to run payload as non-root user.
+     *
+     * @hide
+     */
+    @TestApi
+    public static final String FEATURE_VENDOR_MODULES =
+            IVirtualizationService.FEATURE_VENDOR_MODULES;
+
+    /**
      * Returns a set of flags indicating what this implementation of virtualization is capable of.
      *
      * @see #CAPABILITY_PROTECTED_VM
diff --git a/tests/testapk/src/java/com/android/microdroid/test/MicrodroidTests.java b/tests/testapk/src/java/com/android/microdroid/test/MicrodroidTests.java
index d6183cf..473a560 100644
--- a/tests/testapk/src/java/com/android/microdroid/test/MicrodroidTests.java
+++ b/tests/testapk/src/java/com/android/microdroid/test/MicrodroidTests.java
@@ -1537,11 +1537,7 @@
     @CddTest(requirements = {"9.17/C-1-1"})
     public void payloadIsNotRoot() throws Exception {
         assumeSupportedDevice();
-
-        VirtualMachineManager vmm = getVirtualMachineManager();
-        assumeTrue(
-                VirtualMachineManager.FEATURE_PAYLOAD_NOT_ROOT + " not enabled",
-                vmm.isFeatureEnabled(VirtualMachineManager.FEATURE_PAYLOAD_NOT_ROOT));
+        assumeFeatureEnabled(VirtualMachineManager.FEATURE_PAYLOAD_NOT_ROOT);
 
         VirtualMachineConfig config =
                 newVmConfigBuilder()
@@ -2098,6 +2094,7 @@
     @Test
     public void configuringVendorDiskImageRequiresCustomPermission() throws Exception {
         assumeSupportedDevice();
+        assumeFeatureEnabled(VirtualMachineManager.FEATURE_VENDOR_MODULES);
 
         File vendorDiskImage =
                 new File("/data/local/tmp/cts/microdroid/test_microdroid_vendor_image.img");
@@ -2122,6 +2119,7 @@
     @Test
     public void bootsWithVendorPartition() throws Exception {
         assumeSupportedDevice();
+        assumeFeatureEnabled(VirtualMachineManager.FEATURE_VENDOR_MODULES);
 
         grantPermission(VirtualMachine.USE_CUSTOM_VIRTUAL_MACHINE_PERMISSION);
 
@@ -2249,4 +2247,9 @@
                 .that(KERNEL_VERSION)
                 .isNotEqualTo("5.4");
     }
+
+    private void assumeFeatureEnabled(String featureName) throws Exception {
+        VirtualMachineManager vmm = getVirtualMachineManager();
+        assumeTrue(featureName + " not enabled", vmm.isFeatureEnabled(featureName));
+    }
 }
diff --git a/virtualizationmanager/src/aidl.rs b/virtualizationmanager/src/aidl.rs
index 1ddf129..62fa09d 100644
--- a/virtualizationmanager/src/aidl.rs
+++ b/virtualizationmanager/src/aidl.rs
@@ -35,6 +35,7 @@
     IVirtualMachineCallback::IVirtualMachineCallback,
     IVirtualizationService::IVirtualizationService,
     IVirtualizationService::FEATURE_PAYLOAD_NON_ROOT,
+    IVirtualizationService::FEATURE_VENDOR_MODULES,
     MemoryTrimLevel::MemoryTrimLevel,
     Partition::Partition,
     PartitionType::PartitionType,
@@ -274,6 +275,7 @@
         // TODO(b/298012279): make this scalable.
         match feature {
             FEATURE_PAYLOAD_NON_ROOT => Ok(cfg!(payload_not_root)),
+            FEATURE_VENDOR_MODULES => Ok(cfg!(vendor_modules)),
             _ => {
                 warn!("unknown feature {}", feature);
                 Ok(false)
@@ -326,6 +328,8 @@
         let requester_uid = get_calling_uid();
         let requester_debug_pid = get_calling_pid();
 
+        check_config_features(config)?;
+
         // Allocating VM context checks the MANAGE_VIRTUAL_MACHINE permission.
         let (vm_context, cid, temporary_directory) = self.create_vm_context(requester_debug_pid)?;
 
@@ -1100,6 +1104,24 @@
     }
 }
 
+fn check_no_vendor_modules(config: &VirtualMachineConfig) -> binder::Result<()> {
+    let VirtualMachineConfig::AppConfig(config) = config else { return Ok(()) };
+    if let Some(custom_config) = &config.customConfig {
+        if custom_config.vendorImage.is_some() || custom_config.customKernelImage.is_some() {
+            return Err(anyhow!("vendor modules feature is disabled"))
+                .or_binder_exception(ExceptionCode::UNSUPPORTED_OPERATION);
+        }
+    }
+    Ok(())
+}
+
+fn check_config_features(config: &VirtualMachineConfig) -> binder::Result<()> {
+    if !cfg!(vendor_modules) {
+        check_no_vendor_modules(config)?;
+    }
+    Ok(())
+}
+
 fn clone_or_prepare_logger_fd(
     debug_config: &DebugConfig,
     fd: Option<&ParcelFileDescriptor>,
diff --git a/virtualizationservice/aidl/android/system/virtualizationservice/IVirtualizationService.aidl b/virtualizationservice/aidl/android/system/virtualizationservice/IVirtualizationService.aidl
index 0ee958d..fa50d54 100644
--- a/virtualizationservice/aidl/android/system/virtualizationservice/IVirtualizationService.aidl
+++ b/virtualizationservice/aidl/android/system/virtualizationservice/IVirtualizationService.aidl
@@ -23,6 +23,7 @@
 
 interface IVirtualizationService {
     const String FEATURE_PAYLOAD_NON_ROOT = "com.android.kvm.PAYLOAD_NON_ROOT";
+    const String FEATURE_VENDOR_MODULES = "com.android.kvm.VENDOR_MODULES";
 
     /**
      * Create the VM with the given config file, and return a handle to it ready to start it. If
diff --git a/vm/src/main.rs b/vm/src/main.rs
index 4c44496..e133b8b 100644
--- a/vm/src/main.rs
+++ b/vm/src/main.rs
@@ -98,10 +98,12 @@
     storage_size: Option<u64>,
 
     /// Path to custom kernel image to use when booting Microdroid.
+    #[cfg(vendor_modules)]
     #[arg(long)]
     kernel: Option<PathBuf>,
 
     /// Path to disk image containing vendor-specific modules.
+    #[cfg(vendor_modules)]
     #[arg(long)]
     vendor: Option<PathBuf>,
 
@@ -110,6 +112,29 @@
     devices: Vec<PathBuf>,
 }
 
+impl MicrodroidConfig {
+    #[cfg(vendor_modules)]
+    fn kernel(&self) -> &Option<PathBuf> {
+        &self.kernel
+    }
+
+    #[cfg(not(vendor_modules))]
+    fn kernel(&self) -> Option<PathBuf> {
+        None
+    }
+
+    #[cfg(vendor_modules)]
+    fn vendor(&self) -> &Option<PathBuf> {
+        &self.vendor
+    }
+
+    #[cfg(not(vendor_modules))]
+    #[inline(always)]
+    fn vendor(&self) -> Option<PathBuf> {
+        None
+    }
+}
+
 #[derive(Args)]
 /// Flags for the run_app subcommand
 pub struct RunAppConfig {
diff --git a/vm/src/run.rs b/vm/src/run.rs
index fc8d7e0..1ba9dec 100644
--- a/vm/src/run.rs
+++ b/vm/src/run.rs
@@ -84,25 +84,25 @@
         )?;
     }
 
-    let storage = if let Some(path) = config.microdroid.storage {
+    let storage = if let Some(ref path) = config.microdroid.storage {
         if !path.exists() {
             command_create_partition(
                 service.as_ref(),
-                &path,
+                path,
                 config.microdroid.storage_size.unwrap_or(10 * 1024 * 1024),
                 PartitionType::ENCRYPTEDSTORE,
             )?;
         }
-        Some(open_parcel_file(&path, true)?)
+        Some(open_parcel_file(path, true)?)
     } else {
         None
     };
 
     let kernel =
-        config.microdroid.kernel.as_ref().map(|p| open_parcel_file(p, false)).transpose()?;
+        config.microdroid.kernel().as_ref().map(|p| open_parcel_file(p, false)).transpose()?;
 
     let vendor =
-        config.microdroid.vendor.as_ref().map(|p| open_parcel_file(p, false)).transpose()?;
+        config.microdroid.vendor().as_ref().map(|p| open_parcel_file(p, false)).transpose()?;
 
     let extra_idsig_files: Result<Vec<File>, _> =
         config.extra_idsigs.iter().map(File::open).collect();