+#define PDKIM_MODE_SIGN BIT(0) /* if unset, mode==verify */
+#define PDKIM_DOT_TERM BIT(1) /* dot termination and unstuffing */
+#define PDKIM_SEEN_CR BIT(2)
+#define PDKIM_SEEN_LF BIT(3)
+#define PDKIM_PAST_HDRS BIT(4)
+#define PDKIM_SEEN_EOD BIT(5)
+ unsigned flags;