route: Specify "proto kernel" for ip routes and rules

v1.14 installs routes and rules with specific "proto kernel", v1.15
missed them. Without "proto kernel", it causes troubles when downgrade
from v1.15 to v1.14, as v1.14 is deleting routes with "proto kernel" but
there are no matching ones.

Signed-off-by: Zhichuan Liang <gray.liang@isovalent.com>

pkg/proxy/routes.go

@@ -25,6 +25,7 @@ var (
 		Mark:     int(linux_defaults.MagicMarkIsToProxy),
 		Mask:     linux_defaults.MagicMarkHostMask,
 		Table:    linux_defaults.RouteTableToProxy,
+		Protocol: linux_defaults.RTProto,
 	}
 
 	// Default IPv4 route for local delivery.
@@ -33,7 +34,8 @@ var (
 		Type:   route.RTN_LOCAL,
 		Local:  net.IPv4zero,
 		Device: "lo",
-		Proto:  linux_defaults.RTProto}
+		Proto:  linux_defaults.RTProto,
+	}
 
 	// Default IPv6 route for local delivery.
 	route6 = route.Route{
@@ -104,6 +106,7 @@ var (
 		Mark:     linux_defaults.MagicMarkIsProxy,
 		Mask:     linux_defaults.MagicMarkHostMask,
 		Table:    linux_defaults.RouteTableFromProxy,
+		Protocol: linux_defaults.RTProto,
 	}
 )
 
@@ -124,6 +127,7 @@ func installFromProxyRoutesIPv4(ipv4 net.IP, device string) error {
 		Table:   linux_defaults.RouteTableFromProxy,
 		Nexthop: &ipv4,
 		Device:  device,
+		Proto:   linux_defaults.RTProto,
 	}
 
 	if err := route.ReplaceRule(fromProxyRule); err != nil {
@@ -168,6 +172,7 @@ func installFromProxyRoutesIPv6(ipv6 net.IP, device string) error {
 		Table:   linux_defaults.RouteTableFromProxy,
 		Nexthop: &ipv6,
 		Device:  device,
+		Proto:   linux_defaults.RTProto,
 	}
 
 	if err := route.ReplaceRuleIPv6(fromProxyRule); err != nil {