diff --git a/crypto/message.go b/crypto/message.go
index 60cbd9b..52ddd56 100644
--- a/crypto/message.go
+++ b/crypto/message.go
@@ -2,6 +2,7 @@ package crypto
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"