packetparse: warn on short read

pangbox · Jun 25, 2023 · b04dfe0 · b04dfe0
1 parent 0b26e1f
commit b04dfe0
Showing 1 changed file with 11 additions and 1 deletion.
diff --git a/cmd/packetparse/main.go b/cmd/packetparse/main.go
@@ -133,8 +133,18 @@ func main() {
 
 	err = restruct.Unpack(packet[2:], binary.LittleEndian, message)
 	if err != nil {
-		log.Fatalf("Error parsing packet: %v; partial result: %#v; data: % 02x", err, message, packet)
+		log.Fatalf("Error parsing packet: %v; partial result: %s; data: % 02x", err, spew.Sdump(message), packet)
 	}
 
 	spew.Dump(message)
+
+	sz, err := restruct.SizeOf(message)
+	if err != nil {
+		log.Fatalf("Error getting packet size: %v", err)
+	}
+
+	if sz != len(packet[2:]) {
+		extra := len(packet[2:]) - sz
+		log.Printf("WARNING: %d (%08x) extra bytes... (%d total, %d parsed)", extra, extra, len(packet[2:]), sz)
+	}
 }