crypto: Connect the room key requesting to the rust side

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/DefaultCryptoService.kt

@@ -952,7 +952,23 @@ internal class DefaultCryptoService @Inject constructor(
      * @param event the event to decrypt again.
      */
     override fun reRequestRoomKeyForEvent(event: Event) {
-        // TODO
+        cryptoCoroutineScope.launch(coroutineDispatchers.crypto) {
+            val requestPair = olmMachine!!.requestRoomKey(event)
+
+            if (requestPair.cancellation != null) {
+                when (requestPair.cancellation) {
+                    is Request.ToDevice -> {
+                        sendToDevice(requestPair.cancellation)
+                    }
+                }
+            }
+
+            when(requestPair.keyRequest) {
+                is Request.ToDevice -> {
+                    sendToDevice(requestPair.keyRequest)
+                }
+            }
+        }
     }
 
     /**

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/crypto/OlmMachine.kt

@@ -40,8 +40,10 @@ import org.matrix.android.sdk.internal.session.sync.model.DeviceOneTimeKeysCount
 import org.matrix.android.sdk.internal.session.sync.model.ToDeviceSyncResponse
 import timber.log.Timber
 import uniffi.olm.CryptoStoreErrorException
+import uniffi.olm.DecryptionErrorException
 import uniffi.olm.Device
 import uniffi.olm.DeviceLists
+import uniffi.olm.KeyRequestPair
 import uniffi.olm.Logger
 import uniffi.olm.OlmMachine as InnerMachine
 import uniffi.olm.ProgressListener as RustProgressListener
@@ -370,6 +372,14 @@ internal class OlmMachine(user_id: String, device_id: String, path: File, device
         }
     }
 
+    @Throws(DecryptionErrorException::class)
+    suspend fun requestRoomKey(event: Event): KeyRequestPair = withContext(Dispatchers.IO) {
+        val adapter = MoshiProvider.providesMoshi().adapter<Event>(Event::class.java)
+        val serializedEvent = adapter.toJson(event)
+
+        inner.requestRoomKey(serializedEvent, event.roomId!!)
+    }
+
     /**
      * Export all of our room keys.
      *

rust-sdk/src/lib.rs

@@ -7,7 +7,7 @@ mod responses;
 pub use device::Device;
 pub use error::{CryptoStoreError, DecryptionError, KeyImportError, MachineCreationError};
 pub use logger::{set_logger, Logger};
-pub use machine::{OlmMachine, Sas};
+pub use machine::{OlmMachine, Sas, KeyRequestPair};
 pub use responses::{DeviceLists, KeysImportResult, Request, RequestType};
 
 pub trait ProgressListener {

rust-sdk/src/machine.rs

@@ -47,6 +47,11 @@ pub struct Sas {
     pub request: Request,
 }
 
+pub struct KeyRequestPair {
+    pub cancellation: Option<Request>,
+    pub key_request: Request,
+}
+
 impl OlmMachine {
     /// Create a new `OlmMachine`
     ///
@@ -133,12 +138,13 @@ impl OlmMachine {
     /// [mark_request_as_sent()](#method.mark_request_as_sent) method.
     ///
     /// **Note**: This method call should be locked per call.
-    pub fn outgoing_requests(&self) -> Vec<Request> {
-        self.runtime
-            .block_on(self.inner.outgoing_requests())
+    pub fn outgoing_requests(&self) -> Result<Vec<Request>, CryptoStoreError> {
+        Ok(self
+            .runtime
+            .block_on(self.inner.outgoing_requests())?
             .into_iter()
             .map(|r| r.into())
-            .collect()
+            .collect())
     }
 
     /// Mark a request that was sent to the server as sent.
@@ -418,6 +424,27 @@ impl OlmMachine {
         })
     }
 
+    pub fn request_room_key(
+        &self,
+        event: &str,
+        room_id: &str,
+    ) -> Result<KeyRequestPair, DecryptionError> {
+        let event: SyncMessageEvent<EncryptedEventContent> = serde_json::from_str(event)?;
+        let room_id = RoomId::try_from(room_id)?;
+
+        let (cancel, request) = self
+            .runtime
+            .block_on(self.inner.request_room_key(&event, &room_id))?;
+
+        let cancellation = cancel.map(|r| r.into());
+        let key_request = request.into();
+
+        Ok(KeyRequestPair {
+            cancellation,
+            key_request,
+        })
+    }
+
     /// Export all of our room keys.
     ///
     /// # Arguments

rust-sdk/src/olm.udl

@@ -70,6 +70,11 @@ dictionary Sas {
     Request request;
 };
 
+dictionary KeyRequestPair {
+    Request? cancellation;
+    Request key_request;
+};
+
 [Enum]
 interface Request {
     ToDevice(string request_id, string event_type, string body);
@@ -98,6 +103,7 @@ interface OlmMachine {
     string receive_sync_changes([ByRef] string events,
                               DeviceLists device_changes,
                               record<DOMString, i32> key_counts);
+    [Throws=CryptoStoreError]
     sequence<Request> outgoing_requests();
     [Throws=CryptoStoreError]
     void mark_request_as_sent(
@@ -125,6 +131,9 @@ interface OlmMachine {
     [Throws=CryptoStoreError]
     Sas start_verification([ByRef] Device device);
 
+    [Throws=DecryptionError]
+    KeyRequestPair request_room_key([ByRef] string event, [ByRef] string room_id);
+
     [Throws=CryptoStoreError]
     string export_keys([ByRef] string passphrase, i32 rounds);
     [Throws=KeyImportError]