From 22b9366046be96135875852a673b937f629781dd Mon Sep 17 00:00:00 2001
From: Paul Brook <paul.brook@cocoon.life>
Date: Mon, 8 Oct 2018 17:40:05 +0100
Subject: [PATCH] Check for excess data when unmarshaling binary data

---
 marshal.go | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/marshal.go b/marshal.go
index 7bfb99b..8e28421 100644
--- a/marshal.go
+++ b/marshal.go
@@ -110,7 +110,10 @@ func (m *Macaroon) UnmarshalBinary(data []byte) error {
 	// Copy the data to avoid retaining references to it
 	// in the internal data structures.
 	data = append([]byte(nil), data...)
-	_, err := m.parseBinary(data)
+	rest, err := m.parseBinary(data)
+	if len(rest) != 0 {
+		return fmt.Errorf("trailing binary data")
+	}
 	return err
 }