What I imagine the first step to make overlay deal with routed destinations. Thanks JBK for the overlay_targ_lookup_t changes.

overlay-new-request-target.diff

diff --git a/usr/src/uts/common/sys/overlay_target.h b/usr/src/uts/common/sys/overlay_target.h
index cae193c..d09c776 100644
--- a/usr/src/uts/common/sys/overlay_target.h
+++ b/usr/src/uts/common/sys/overlay_target.h
@@ -29,10 +29,21 @@
 extern "C" {
 #endif
 
+/*
+ * The answer we want at the end of the day.  What are the target and source
+ * MAC addresses and VLAN ID (because the source VL2 MAC header may need to be
+ * rewritten if the UL3 is in a far-remote/routed network), target UL3 IP and
+ * target UL3 UDP port?
+ *
+ * If a supplied MAC address or vlan is 0, do NOT replace the existing VL2
+ * field with it.
+ */
 typedef struct overlay_target_point {
 	uint8_t		otp_mac[ETHERADDRL];
-	struct in6_addr	otp_ip;
+	uint8_t		otp_srcmac[ETHERADDRL];
 	uint16_t	otp_port;
+	uint16_t	otp_vlan;
+	struct in6_addr	otp_ip;
 } overlay_target_point_t;
 
 #define	OVERLAY_TARG_IOCTL	(('o' << 24) | ('v' << 16) | ('t' << 8))
@@ -159,12 +170,22 @@ typedef struct overlay_targ_lookup {
 	uint64_t	otl_vnetid;
 	uint64_t	otl_hdrsize;
 	uint64_t	otl_pktsize;
+	uint32_t	otl_dcid;	/* */
 	uint8_t		otl_srcaddr[ETHERADDRL];
-	uint8_t		otl_dstaddr[ETHERADDRL];
-	uint32_t	otl_dsttype;
+	boolean_t   otl_l3req;
+	union {
+		struct in6_addr otlu_vl3addr;
+		struct {
+			uint8_t otlu_dstaddr[ETHERADDRL];
+			uint32_t oltu_dsttype;
+		} oltu_vl2addr;
+	} otl_dst;
 	uint32_t	otl_sap;
 	int32_t		otl_vlan;
 } overlay_targ_lookup_t;
+#define otl_dstaddr otl_dst.otlu_vl2addr.otlu_dstaddr
+#define otl_dsttype otl_dst.otlu_vl2addr.otlu_dsttype
+#define otl_dstvl3addr otl_dst.otlu_vl3addr
 
 typedef struct overlay_targ_resp {
 	uint64_t	otr_reqid;