Add user rule item

route/rule.go

@@ -82,8 +82,13 @@ func NewDefaultRule(router adapter.Router, logger log.ContextLogger, options opt
 			return nil, E.New("invalid network: ", options.Network)
 		}
 	}
+	if len(options.User) > 0 {
+		item := NewUserItem(options.User)
+		rule.items = append(rule.items, item)
+		rule.allItems = append(rule.allItems, item)
+	}
 	if len(options.Protocol) > 0 {
-		item := NewProtocolItem(options.Protocol)
+		item := NewUserItem(options.Protocol)
 		rule.items = append(rule.items, item)
 		rule.allItems = append(rule.allItems, item)
 	}

route/rule_dns.go

@@ -66,8 +66,13 @@ func NewDefaultDNSRule(router adapter.Router, logger log.ContextLogger, options
 			return nil, E.New("invalid network: ", options.Network)
 		}
 	}
+	if len(options.User) > 0 {
+		item := NewUserItem(options.User)
+		rule.items = append(rule.items, item)
+		rule.allItems = append(rule.allItems, item)
+	}
 	if len(options.Protocol) > 0 {
-		item := NewProtocolItem(options.Protocol)
+		item := NewUserItem(options.Protocol)
 		rule.items = append(rule.items, item)
 		rule.allItems = append(rule.allItems, item)
 	}

route/rule_user.go

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