Feature: add DST-PORT and SRC-PORT

rules/port.go

@@ -0,0 +1,47 @@
+package rules
+
+import (
+	"strconv"
+
+	C "github.com/Dreamacro/clash/constant"
+)
+
+type Port struct {
+	adapter  string
+	port     string
+	isSource bool
+}
+
+func (p *Port) RuleType() C.RuleType {
+	if p.isSource {
+		return C.SrcPort
+	}
+	return C.DstPort
+}
+
+func (p *Port) IsMatch(metadata *C.Metadata) bool {
+	if p.isSource {
+		return metadata.SrcPort == p.port
+	}
+	return metadata.DstPort == p.port
+}
+
+func (p *Port) Adapter() string {
+	return p.adapter
+}
+
+func (p *Port) Payload() string {
+	return p.port
+}
+
+func NewPort(port string, adapter string, isSource bool) *Port {
+	_, err := strconv.Atoi(port)
+	if err != nil {
+		return nil
+	}
+	return &Port{
+		adapter:  adapter,
+		port:     port,
+		isSource: isSource,
+	}
+}