+#define ND_RA_FLAG_HOME_AGENT 0x20
+
+/*
+ * Router preference values based on draft-draves-ipngwg-router-selection-01.
+ * These are non-standard definitions.
+ */
+#define ND_RA_FLAG_RTPREF_MASK 0x18 /* 00011000 */
+
+#define ND_RA_FLAG_RTPREF_HIGH 0x08 /* 00001000 */
+#define ND_RA_FLAG_RTPREF_MEDIUM 0x00 /* 00000000 */
+#define ND_RA_FLAG_RTPREF_LOW 0x18 /* 00011000 */
+#define ND_RA_FLAG_RTPREF_RSV 0x10 /* 00010000 */
+