add ovn0 ipv6 link local address

Signed-off-by: clyi <clyi@alauda.io>

pkg/daemon/ovs_linux.go

@@ -835,6 +835,29 @@ func configureMirrorLink(portName string, _ int) error {
 	return nil
 }
 
+// Convert MAC address to EUI-64 and generate link-local IPv6 address
+func macToLinkLocalIPv6(mac net.HardwareAddr) (net.IP, error) {
+	if len(mac) != 6 {
+		return nil, fmt.Errorf("invalid MAC address length")
+	}
+
+	// Create EUI-64 format
+	eui64 := make([]byte, 8)
+	copy(eui64[0:3], mac[0:3]) // Copy the first 3 bytes
+	eui64[3] = 0xff            // Insert ff
+	eui64[4] = 0xfe            // Insert fe
+	copy(eui64[5:], mac[3:])   // Copy the last 3 bytes
+
+	// Flip the 7th bit of the first byte
+	eui64[0] ^= 0x02
+
+	// Prepend the link-local prefix
+	linkLocalIPv6 := net.IP{0xfe, 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+	copy(linkLocalIPv6[8:], eui64)
+
+	return linkLocalIPv6, nil
+}
+
 func configureNic(link, ip string, macAddr net.HardwareAddr, mtu int, detectIPConflict, setUfoOff bool) error {
 	nodeLink, err := netlink.LinkByName(link)
 	if err != nil {
@@ -868,14 +891,32 @@ func configureNic(link, ip string, macAddr net.HardwareAddr, mtu int, detectIPCo
 	if err != nil {
 		return fmt.Errorf("can not get addr %s: %v", nodeLink, err)
 	}
+
+	needAddIPv6LinkLocal := true
 	for _, ipAddr := range ipAddrs {
 		if ipAddr.IP.IsLinkLocalUnicast() {
 			// skip 169.254.0.0/16 and fe80::/10
+			if util.CheckProtocol(ipAddr.IP.String()) == kubeovnv1.ProtocolIPv6 {
+				needAddIPv6LinkLocal = false
+			}
 			continue
 		}
 		ipDelMap[ipAddr.IPNet.String()] = ipAddr
 	}
 
+	if needAddIPv6LinkLocal {
+		linkLocal, err := macToLinkLocalIPv6(macAddr)
+		if err != nil {
+			return fmt.Errorf("failed to generate link-local address: %v", err)
+		}
+		ipAddMap[linkLocal.String()] = netlink.Addr{
+			IPNet: &net.IPNet{
+				IP:   linkLocal,
+				Mask: net.CIDRMask(64, 128),
+			},
+		}
+	}
+
 	for _, ipStr := range strings.Split(ip, ",") {
 		// Do not reassign same address for link
 		if _, ok := ipDelMap[ipStr]; ok {
@@ -896,6 +937,7 @@ func configureNic(link, ip string, macAddr net.HardwareAddr, mtu int, detectIPCo
 			return fmt.Errorf("delete address %s: %v", addr, err)
 		}
 	}
+
 	for ip, addr := range ipAddMap {
 		if detectIPConflict && addr.IP.To4() != nil {
 			ip := addr.IP.String()