crypto: Connect the key exporting to the rust-sdk export method

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

@@ -835,18 +835,12 @@ internal class DefaultCryptoService @Inject constructor(
      * Export the crypto keys
      *
      * @param password         the password
-     * @param anIterationCount the encryption iteration count (0 means no encryption)
+     * @param anIterationCount the encryption iteration count
      */
     private suspend fun exportRoomKeys(password: String, anIterationCount: Int): ByteArray {
         return withContext(coroutineDispatchers.crypto) {
-            val iterationCount = max(0, anIterationCount)
-
-            val exportedSessions = cryptoStore.getInboundGroupSessions().mapNotNull { it.exportKeys() }
-
-            val adapter = MoshiProvider.providesMoshi()
-                    .adapter(List::class.java)
-
-            MXMegolmExportEncryption.encryptMegolmKeyFile(adapter.toJson(exportedSessions), password, iterationCount)
+            val iterationCount = max(10000, anIterationCount)
+            olmMachine!!.exportKeys(password, iterationCount)
         }
     }
 

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

@@ -38,6 +38,7 @@ import uniffi.olm.Logger
 import uniffi.olm.OlmMachine as InnerMachine
 import uniffi.olm.Request
 import uniffi.olm.RequestType
+import uniffi.olm.CryptoStoreErrorException
 import uniffi.olm.Sas as InnerSas
 import uniffi.olm.setLogger
 
@@ -179,6 +180,11 @@ internal class OlmMachine(user_id: String, device_id: String, path: File) {
         }
     }
 
+    @Throws(CryptoStoreErrorException::class)
+    suspend fun exportKeys(passphrase: String, rounds: Int): ByteArray = withContext(Dispatchers.IO) {
+        inner.exportKeys(passphrase, rounds).toByteArray()
+    }
+
     @Throws(MXCryptoError::class)
     suspend fun decryptRoomEvent(event: Event): MXEventDecryptionResult = withContext(Dispatchers.IO) {
         val adapter = MoshiProvider.providesMoshi().adapter<Event>(Event::class.java)

rust-sdk/src/error.rs

@@ -15,6 +15,8 @@ pub enum CryptoStoreError {
     CryptoStore(#[from] InnerStoreError),
     #[error(transparent)]
     OlmError(#[from] OlmError),
+    #[error(transparent)]
+    Serialization(#[from] serde_json::Error),
 }
 
 #[derive(Debug, thiserror::Error)]

rust-sdk/src/machine.rs

@@ -10,8 +10,7 @@ use tokio::runtime::Runtime;
 use matrix_sdk_common::{
     api::r0::{
         keys::{
-            claim_keys::{Request as KeysClaimRequest, Response as KeysClaimResponse},
-            get_keys::Response as KeysQueryResponse,
+            claim_keys::Response as KeysClaimResponse, get_keys::Response as KeysQueryResponse,
             upload_keys::Response as KeysUploadResponse,
         },
         sync::sync_events::{DeviceLists as RumaDeviceLists, ToDevice},
@@ -26,8 +25,8 @@ use matrix_sdk_common::{
 };
 
 use matrix_sdk_crypto::{
-    EncryptionSettings, IncomingResponse, OlmMachine as InnerMachine, OutgoingRequest,
-    ToDeviceRequest,
+    encrypt_key_export, EncryptionSettings, IncomingResponse, OlmMachine as InnerMachine,
+    OutgoingRequest, ToDeviceRequest,
 };
 
 use crate::error::{CryptoStoreError, DecryptionError, MachineCreationError};
@@ -420,6 +419,15 @@ impl OlmMachine {
         serde_json::to_string(&encrypted_content).unwrap()
     }
 
+    pub fn export_keys(&self, passphrase: &str, rounds: i32) -> Result<String, CryptoStoreError> {
+        let keys = self.runtime.block_on(self.inner.export_keys(|_| true))?;
+
+        let encrypted = encrypt_key_export(&keys, passphrase, rounds as u32)
+            .map_err(CryptoStoreError::Serialization)?;
+
+        Ok(encrypted)
+    }
+
     pub fn decrypt_room_event(
         &self,
         event: &str,

rust-sdk/src/olm.udl

@@ -16,6 +16,7 @@ enum MachineCreationError {
 enum CryptoStoreError {
     "CryptoStore",
     "OlmError",
+    "Serialization",
 };
 
 [Error]
@@ -102,4 +103,7 @@ interface OlmMachine {
 
     [Throws=CryptoStoreError]
     Sas start_verification([ByRef] Device device);
+
+    [Throws=CryptoStoreError]
+    string export_keys([ByRef] string passphrase, i32 rounds);
 };