Add Accessor::from_binder
This allows other processes to host the Accessor object from libbinder.
This can be useful when another process has the sepolicy permissions to
create the connection.
Test: atest rustBinderTest
Bug: 358427181
Change-Id: Iedc51e2fa5b50e91438690d5d551156927a91807
diff --git a/libs/binder/rust/src/system_only.rs b/libs/binder/rust/src/system_only.rs
index 3da59ab..1a58d6b 100644
--- a/libs/binder/rust/src/system_only.rs
+++ b/libs/binder/rust/src/system_only.rs
@@ -91,6 +91,32 @@
Accessor { accessor }
}
+ /// Creates a new Accessor instance based on an existing Accessor's binder.
+ /// This is useful when the Accessor instance is hosted in another process
+ /// that has the permissions to create the socket connection FD.
+ ///
+ /// The `instance` argument must match the instance that the original Accessor
+ /// is responsible for.
+ /// `instance` must not contain null bytes and is used to create a CString to
+ /// pass through FFI.
+ /// The `binder` argument must be a valid binder from an Accessor
+ pub fn from_binder(instance: &str, binder: SpIBinder) -> Option<Accessor> {
+ let inst = CString::new(instance).unwrap();
+
+ // Safety: All `SpIBinder` objects (the `binder` argument) hold a valid pointer
+ // to an `AIBinder` that is guaranteed to remain valid for the lifetime of the
+ // SpIBinder. `ABinderRpc_Accessor_fromBinder` creates a new pointer to that binder
+ // that it is responsible for.
+ // The `inst` argument is a new CString that will copied by
+ // `ABinderRpc_Accessor_fromBinder` and not modified.
+ let accessor =
+ unsafe { sys::ABinderRpc_Accessor_fromBinder(inst.as_ptr(), binder.as_raw()) };
+ if accessor.is_null() {
+ return None;
+ }
+ Some(Accessor { accessor })
+ }
+
/// Get the underlying binder for this Accessor for when it needs to be either
/// registered with service manager or sent to another process.
pub fn as_binder(&self) -> Option<SpIBinder> {
diff --git a/libs/binder/rust/tests/integration.rs b/libs/binder/rust/tests/integration.rs
index 0e793e5..da4f128 100644
--- a/libs/binder/rust/tests/integration.rs
+++ b/libs/binder/rust/tests/integration.rs
@@ -1038,6 +1038,34 @@
assert!(deleted.load(Ordering::Relaxed));
}
+ #[test]
+ fn test_accessor_from_accessor_binder() {
+ let get_connection_info = move |_instance: &str| None;
+ let accessor = Accessor::new("foo.service", get_connection_info);
+ let accessor2 =
+ Accessor::from_binder("foo.service", accessor.as_binder().unwrap()).unwrap();
+ assert_eq!(accessor.as_binder(), accessor2.as_binder());
+ }
+
+ #[test]
+ fn test_accessor_from_non_accessor_binder() {
+ let service_name = "rust_test_ibinder";
+ let _process = ScopedServiceProcess::new(service_name);
+ let binder = binder::get_service(service_name).unwrap();
+ assert!(binder.is_binder_alive());
+
+ let accessor = Accessor::from_binder("rust_test_ibinder", binder);
+ assert!(accessor.is_none());
+ }
+
+ #[test]
+ fn test_accessor_from_wrong_accessor_binder() {
+ let get_connection_info = move |_instance: &str| None;
+ let accessor = Accessor::new("foo.service", get_connection_info);
+ let accessor2 = Accessor::from_binder("NOT.foo.service", accessor.as_binder().unwrap());
+ assert!(accessor2.is_none());
+ }
+
#[tokio::test]
async fn reassociate_rust_binder_async() {
let service_name = "testing_service";