diff --git a/autobahn/src/main/java/xbr/network/crypto/SecretBox.java b/autobahn/src/main/java/xbr/network/crypto/SecretBox.java
index 9fa5e9dd..74f4688b 100644
--- a/autobahn/src/main/java/xbr/network/crypto/SecretBox.java
+++ b/autobahn/src/main/java/xbr/network/crypto/SecretBox.java
@@ -4,6 +4,7 @@
 
 import static io.xconn.cryptology.SecretBox.box;
 import static io.xconn.cryptology.SecretBox.boxOpen;
+import static io.xconn.cryptology.Util.checkLength;
 import static io.xconn.cryptology.Util.generateRandomBytesArray;
 
 import static xbr.network.Util.NONCE_SIZE;
@@ -35,9 +36,4 @@ public byte[] decrypt(byte[] ciphertext) {
         byte[] message = Arrays.copyOfRange(ciphertext, NONCE_SIZE, ciphertext.length);
         return boxOpen(nonce, message, mKey);
     }
-
-    private void checkLength(byte[] data, int size) {
-        if (data == null || data.length != size)
-            throw new IllegalArgumentException("Invalid size: " + data.length);
-    }
 }