Cloud migration: encryption key is a byte slice (#90739)

* Cloud migrations: include metadata returned by CMS in the index file

* Cloud migrations: make EncryptionKey a []byte in structs

* test

pkg/services/cloudmigration/cloudmigrationimpl/snapshot_mgmt.go

@@ -188,7 +188,7 @@ func (s *Service) buildSnapshot(ctx context.Context, signedInUser *user.SignedIn
 
 	// Use GMS public key + the grafana generated private private key to encrypt snapshot files.
 	snapshotWriter, err := snapshot.NewSnapshotWriter(contracts.AssymetricKeys{
-		Public:  []byte(snapshotMeta.EncryptionKey),
+		Public:  snapshotMeta.EncryptionKey,
 		Private: privateKey[:],
 	},
 		crypto.NewNacl(),

pkg/services/cloudmigration/cloudmigrationimpl/xorm_store.go

@@ -413,27 +413,22 @@ func (ss *sqlStore) decryptToken(ctx context.Context, cm *cloudmigration.CloudMi
 }
 
 func (ss *sqlStore) encryptKey(ctx context.Context, snapshot *cloudmigration.CloudMigrationSnapshot) error {
-	s, err := ss.secretsService.Encrypt(ctx, []byte(snapshot.EncryptionKey), secrets.WithoutScope())
+	s, err := ss.secretsService.Encrypt(ctx, snapshot.EncryptionKey, secrets.WithoutScope())
 	if err != nil {
 		return fmt.Errorf("encrypting key: %w", err)
 	}
 
-	snapshot.EncryptionKey = base64.StdEncoding.EncodeToString(s)
+	snapshot.EncryptionKey = s
 
 	return nil
 }
 
 func (ss *sqlStore) decryptKey(ctx context.Context, snapshot *cloudmigration.CloudMigrationSnapshot) error {
-	decoded, err := base64.StdEncoding.DecodeString(snapshot.EncryptionKey)
-	if err != nil {
-		return fmt.Errorf("key could not be decoded")
-	}
-
-	t, err := ss.secretsService.Decrypt(ctx, decoded)
+	t, err := ss.secretsService.Decrypt(ctx, snapshot.EncryptionKey)
 	if err != nil {
 		return fmt.Errorf("decrypting key: %w", err)
 	}
-	snapshot.EncryptionKey = string(t)
+	snapshot.EncryptionKey = t
 
 	return nil
 }