datapath/linux/route: add support for rule protocol

Add support for fib rule protocol. Defaults to 0 (unspec) to be
backwards compatible with the old behaviour.

Signed-off-by: Nikolay Aleksandrov <[email protected]>

pkg/datapath/linux/route/route_linux.go

@@ -320,6 +320,9 @@ type Rule struct {
 
 	// Table is the routing table to look up if the rule matches
 	Table int
+
+	// Protocol is the routing rule protocol (e.g. proto unspec/kernel)
+	Protocol uint8
 }
 
 // String returns the string representation of a Rule (adhering to the Stringer
@@ -355,6 +358,8 @@ func (r Rule) String() string {
 		str += fmt.Sprintf(" mark 0x%x mask 0x%x", r.Mark, r.Mask)
 	}
 
+	str += fmt.Sprintf(" proto %s", netlink.RouteProtocol(r.Protocol))
+
 	return str
 }
 
@@ -380,6 +385,10 @@ func lookupRule(spec Rule, family int) (bool, error) {
 			continue
 		}
 
+		if spec.Protocol != 0 && r.Protocol != spec.Protocol {
+			continue
+		}
+
 		if r.Table == spec.Table {
 			return true, nil
 		}
@@ -458,6 +467,7 @@ func replaceRule(spec Rule, family int) error {
 	rule.Priority = spec.Priority
 	rule.Src = spec.From
 	rule.Dst = spec.To
+	rule.Protocol = spec.Protocol
 	return netlink.RuleAdd(rule)
 }
 
@@ -480,6 +490,7 @@ func deleteRule(spec Rule, family int) error {
 	rule.Src = spec.From
 	rule.Dst = spec.To
 	rule.Family = family
+	rule.Protocol = spec.Protocol
 	return netlink.RuleDel(rule)
 }