Implement route rules

adapter/route/rule_protocol.go

@@ -0,0 +1,37 @@
+package route
+
+import (
+	"strings"
+
+	"github.com/sagernet/sing-box/adapter"
+	F "github.com/sagernet/sing/common/format"
+)
+
+var _ RuleItem = (*ProtocolItem)(nil)
+
+type ProtocolItem struct {
+	protocols   []string
+	protocolMap map[string]bool
+}
+
+func NewProtocolItem(protocols []string) *ProtocolItem {
+	protocolMap := make(map[string]bool)
+	for _, protocol := range protocols {
+		protocolMap[protocol] = true
+	}
+	return &ProtocolItem{
+		protocols:   protocols,
+		protocolMap: protocolMap,
+	}
+}
+
+func (r *ProtocolItem) Match(metadata *adapter.InboundContext) bool {
+	return r.protocolMap[metadata.Protocol]
+}
+
+func (r *ProtocolItem) String() string {
+	if len(r.protocols) == 1 {
+		return F.ToString("protocol=", r.protocols[0])
+	}
+	return F.ToString("protocol=[", strings.Join(r.protocols, " "), "]")
+}