Inbound rule support

adapter/route/rule_inbound.go

@@ -0,0 +1,35 @@
+package route
+
+import (
+	"strings"
+
+	"github.com/sagernet/sing-box/adapter"
+	F "github.com/sagernet/sing/common/format"
+)
+
+var _ RuleItem = (*InboundRule)(nil)
+
+type InboundRule struct {
+	inbounds   []string
+	inboundMap map[string]bool
+}
+
+func NewInboundRule(inbounds []string) RuleItem {
+	rule := &InboundRule{inbounds, make(map[string]bool)}
+	for _, inbound := range inbounds {
+		rule.inboundMap[inbound] = true
+	}
+	return rule
+}
+
+func (r *InboundRule) Match(metadata adapter.InboundContext) bool {
+	return r.inboundMap[metadata.Inbound]
+}
+
+func (r *InboundRule) String() string {
+	if len(r.inbounds) == 1 {
+		return F.ToString("inbound=", r.inbounds[0])
+	} else {
+		return F.ToString("inbound=[", strings.Join(r.inbounds, " "), "]")
+	}
+}