Add entry to keyBackupService to expose deriveKey, which becomes internal

And format code

matrix-sdk-android/src/main/java/org/matrix/android/sdk/api/session/crypto/keysbackup/KeysBackupService.kt

@@ -214,4 +214,9 @@ interface KeysBackupService {
     fun getKeyBackupRecoveryKeyInfo(): SavedKeyBackupKeyInfo?
 
     fun isValidRecoveryKeyForCurrentVersion(recoveryKey: String, callback: MatrixCallback<Boolean>)
+
+    fun computePrivateKey(passphrase: String,
+                          privateKeySalt: String,
+                          privateKeyIterations: Int,
+                          progressListener: ProgressListener): ByteArray
 }

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

@@ -36,9 +36,15 @@ import org.matrix.android.sdk.api.session.crypto.keysbackup.KeysBackupLastVersio
 import org.matrix.android.sdk.api.session.crypto.keysbackup.KeysBackupService
 import org.matrix.android.sdk.api.session.crypto.keysbackup.KeysBackupState
 import org.matrix.android.sdk.api.session.crypto.keysbackup.KeysBackupStateListener
+import org.matrix.android.sdk.api.session.crypto.keysbackup.KeysBackupVersionTrust
+import org.matrix.android.sdk.api.session.crypto.keysbackup.KeysVersion
+import org.matrix.android.sdk.api.session.crypto.keysbackup.KeysVersionResult
+import org.matrix.android.sdk.api.session.crypto.keysbackup.MegolmBackupCreationInfo
 import org.matrix.android.sdk.api.session.crypto.keysbackup.SavedKeyBackupKeyInfo
 import org.matrix.android.sdk.api.session.crypto.keysbackup.computeRecoveryKey
 import org.matrix.android.sdk.api.session.crypto.keysbackup.extractCurveKeyFromRecoveryKey
+import org.matrix.android.sdk.api.session.crypto.keysbackup.toKeysVersionResult
+import org.matrix.android.sdk.api.session.crypto.model.ImportRoomKeysResult
 import org.matrix.android.sdk.api.util.awaitCallback
 import org.matrix.android.sdk.api.util.fromBase64
 import org.matrix.android.sdk.internal.crypto.MXCRYPTO_ALGORITHM_MEGOLM_BACKUP
@@ -46,18 +52,13 @@ import org.matrix.android.sdk.internal.crypto.MXOlmDevice
 import org.matrix.android.sdk.internal.crypto.MegolmSessionData
 import org.matrix.android.sdk.internal.crypto.ObjectSigner
 import org.matrix.android.sdk.internal.crypto.actions.MegolmSessionDataImporter
-import org.matrix.android.sdk.api.session.crypto.keysbackup.KeysBackupVersionTrust
 import org.matrix.android.sdk.internal.crypto.keysbackup.model.KeysBackupVersionTrustSignature
 import org.matrix.android.sdk.internal.crypto.keysbackup.model.MegolmBackupAuthData
-import org.matrix.android.sdk.api.session.crypto.keysbackup.MegolmBackupCreationInfo
 import org.matrix.android.sdk.internal.crypto.keysbackup.model.SignalableMegolmBackupAuthData
 import org.matrix.android.sdk.internal.crypto.keysbackup.model.rest.BackupKeysResult
 import org.matrix.android.sdk.internal.crypto.keysbackup.model.rest.CreateKeysBackupVersionBody
 import org.matrix.android.sdk.internal.crypto.keysbackup.model.rest.KeyBackupData
 import org.matrix.android.sdk.internal.crypto.keysbackup.model.rest.KeysBackupData
-import org.matrix.android.sdk.api.session.crypto.keysbackup.KeysVersion
-import org.matrix.android.sdk.api.session.crypto.keysbackup.KeysVersionResult
-import org.matrix.android.sdk.api.session.crypto.keysbackup.toKeysVersionResult
 import org.matrix.android.sdk.internal.crypto.keysbackup.model.rest.RoomKeysBackupData
 import org.matrix.android.sdk.internal.crypto.keysbackup.model.rest.UpdateKeysBackupVersionBody
 import org.matrix.android.sdk.internal.crypto.keysbackup.tasks.CreateKeysBackupVersionTask
@@ -74,7 +75,6 @@ import org.matrix.android.sdk.internal.crypto.keysbackup.tasks.StoreRoomSessionD
 import org.matrix.android.sdk.internal.crypto.keysbackup.tasks.StoreRoomSessionsDataTask
 import org.matrix.android.sdk.internal.crypto.keysbackup.tasks.StoreSessionsDataTask
 import org.matrix.android.sdk.internal.crypto.keysbackup.tasks.UpdateKeysBackupVersionTask
-import org.matrix.android.sdk.api.session.crypto.model.ImportRoomKeysResult
 import org.matrix.android.sdk.internal.crypto.model.OlmInboundGroupSessionWrapper2
 import org.matrix.android.sdk.internal.crypto.store.IMXCryptoStore
 import org.matrix.android.sdk.internal.crypto.store.db.model.KeysBackupDataEntity
@@ -1099,6 +1099,13 @@ internal class DefaultKeysBackupService @Inject constructor(
         }
     }
 
+    override fun computePrivateKey(passphrase: String,
+                                   privateKeySalt: String,
+                                   privateKeyIterations: Int,
+                                   progressListener: ProgressListener): ByteArray {
+         return deriveKey(passphrase, privateKeySalt, privateKeyIterations, progressListener)
+    }
+
     /**
      * Enable backing up of keys.
      * This method will update the state and will start sending keys in nominal case

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

@@ -30,13 +30,14 @@ import kotlin.experimental.xor
 private const val SALT_LENGTH = 32
 private const val DEFAULT_ITERATION = 500_000
 
-data class GeneratePrivateKeyResult(
+internal data class GeneratePrivateKeyResult(
         // The private key
         val privateKey: ByteArray,
         // the salt used to generate the private key
         val salt: String,
         // number of key derivations done on the generated private key.
-        val iterations: Int)
+        val iterations: Int
+)
 
 /**
  * Compute a private key from a password.
@@ -46,7 +47,9 @@ data class GeneratePrivateKeyResult(
  * @return a {privateKey, salt, iterations} tuple.
  */
 @WorkerThread
-fun generatePrivateKeyWithPassword(password: String, progressListener: ProgressListener?): GeneratePrivateKeyResult {
+internal fun generatePrivateKeyWithPassword(password: String,
+                                            progressListener: ProgressListener?
+): GeneratePrivateKeyResult {
     val salt = generateSalt()
     val iterations = DEFAULT_ITERATION
     val privateKey = deriveKey(password, salt, iterations, progressListener)
@@ -65,10 +68,10 @@ fun generatePrivateKeyWithPassword(password: String, progressListener: ProgressL
  * @return a private key.
  */
 @WorkerThread
-fun retrievePrivateKeyWithPassword(password: String,
-                                   salt: String,
-                                   iterations: Int,
-                                   progressListener: ProgressListener? = null): ByteArray {
+internal fun retrievePrivateKeyWithPassword(password: String,
+                                            salt: String,
+                                            iterations: Int,
+                                            progressListener: ProgressListener? = null): ByteArray {
     return deriveKey(password, salt, iterations, progressListener)
 }
 
@@ -83,10 +86,10 @@ fun retrievePrivateKeyWithPassword(password: String,
  * @return a private key.
  */
 @WorkerThread
-fun deriveKey(password: String,
-              salt: String,
-              iterations: Int,
-              progressListener: ProgressListener?): ByteArray {
+internal fun deriveKey(password: String,
+                       salt: String,
+                       iterations: Int,
+                       progressListener: ProgressListener?): ByteArray {
     // Note: copied and adapted from MXMegolmExportEncryption
     val t0 = System.currentTimeMillis()
 

vector/src/main/java/im/vector/app/features/crypto/recover/BackupToQuadSMigrationTask.kt

@@ -32,7 +32,6 @@ import org.matrix.android.sdk.api.session.securestorage.SharedSecretStorageServi
 import org.matrix.android.sdk.api.session.securestorage.SsssKeyCreationInfo
 import org.matrix.android.sdk.api.util.awaitCallback
 import org.matrix.android.sdk.api.util.toBase64NoPadding
-import org.matrix.android.sdk.internal.crypto.keysbackup.deriveKey
 import timber.log.Timber
 import java.util.UUID
 import javax.inject.Inject
@@ -72,14 +71,18 @@ class BackupToQuadSMigrationTask @Inject constructor(
                         extractCurveKeyFromRecoveryKey(params.recoveryKey)
                     } else if (!params.passphrase.isNullOrEmpty() && version.getAuthDataAsMegolmBackupAuthData()?.privateKeySalt != null) {
                         version.getAuthDataAsMegolmBackupAuthData()?.let { authData ->
-                            deriveKey(params.passphrase, authData.privateKeySalt!!, authData.privateKeyIterations!!, object : ProgressListener {
-                                override fun onProgress(progress: Int, total: Int) {
-                                    params.progressListener?.onProgress(WaitingViewData(
-                                            stringProvider.getString(R.string.bootstrap_progress_checking_backup_with_info,
-                                                    "$progress/$total")
-                                    ))
-                                }
-                            })
+                            keysBackupService.computePrivateKey(
+                                    params.passphrase,
+                                    authData.privateKeySalt!!,
+                                    authData.privateKeyIterations!!,
+                                    object : ProgressListener {
+                                        override fun onProgress(progress: Int, total: Int) {
+                                            params.progressListener?.onProgress(WaitingViewData(
+                                                    stringProvider.getString(R.string.bootstrap_progress_checking_backup_with_info,
+                                                            "$progress/$total")
+                                            ))
+                                        }
+                                    })
                         }
                     } else null)
                             ?: return Result.IllegalParams