Add accept empty DNS rule option

route/router_dns.go

@@ -104,7 +104,8 @@ func (r *Router) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.Msg, er
 	response, cached = r.dnsClient.ExchangeCache(ctx, message)
 	if !cached {
 		var metadata *adapter.InboundContext
-		ctx, metadata = adapter.AppendContext(ctx)
+		ctx, metadata = adapter.ExtendContext(ctx)
+		metadata.Destination = M.Socksaddr{}
 		if len(message.Question) > 0 {
 			metadata.QueryType = message.Question[0].Qtype
 			switch metadata.QueryType {
@@ -126,12 +127,16 @@ func (r *Router) Exchange(ctx context.Context, message *mDNS.Msg) (*mDNS.Msg, er
 				dnsCtx       context.Context
 				addressLimit bool
 			)
-
 			dnsCtx, transport, strategy, rule, ruleIndex = r.matchDNS(ctx, true, ruleIndex, isAddressQuery(message))
+			dnsCtx = adapter.OverrideContext(dnsCtx)
 			if rule != nil && rule.WithAddressLimit() {
 				addressLimit = true
 				response, err = r.dnsClient.ExchangeWithResponseCheck(dnsCtx, transport, message, strategy, func(response *mDNS.Msg) bool {
-					metadata.DestinationAddresses, _ = dns.MessageToAddresses(response)
+					addresses, addrErr := dns.MessageToAddresses(response)
+					if addrErr != nil {
+						return false
+					}
+					metadata.DestinationAddresses = addresses
 					return rule.MatchAddressLimit(metadata)
 				})
 			} else {
@@ -190,7 +195,8 @@ func (r *Router) Lookup(ctx context.Context, domain string, strategy dns.DomainS
 		return responseAddrs, nil
 	}
 	r.dnsLogger.DebugContext(ctx, "lookup domain ", domain)
-	ctx, metadata := adapter.AppendContext(ctx)
+	ctx, metadata := adapter.ExtendContext(ctx)
+	metadata.Destination = M.Socksaddr{}
 	metadata.Domain = domain
 	var (
 		transport         dns.Transport
@@ -204,9 +210,8 @@ func (r *Router) Lookup(ctx context.Context, domain string, strategy dns.DomainS
 			dnsCtx       context.Context
 			addressLimit bool
 		)
-		metadata.ResetRuleCache()
-		metadata.DestinationAddresses = nil
 		dnsCtx, transport, transportStrategy, rule, ruleIndex = r.matchDNS(ctx, false, ruleIndex, true)
+		dnsCtx = adapter.OverrideContext(dnsCtx)
 		if strategy == dns.DomainStrategyAsIS {
 			strategy = transportStrategy
 		}

route/rule_default.go

@@ -205,7 +205,7 @@ func NewDefaultRule(router adapter.Router, logger log.ContextLogger, options opt
 		rule.allItems = append(rule.allItems, item)
 	}
 	if len(options.RuleSet) > 0 {
-		item := NewRuleSetItem(router, options.RuleSet, options.RuleSetIPCIDRMatchSource)
+		item := NewRuleSetItem(router, options.RuleSet, options.RuleSetIPCIDRMatchSource, false)
 		rule.items = append(rule.items, item)
 		rule.allItems = append(rule.allItems, item)
 	}

route/rule_dns.go

@@ -219,7 +219,7 @@ func NewDefaultDNSRule(router adapter.Router, logger log.ContextLogger, options
 		rule.allItems = append(rule.allItems, item)
 	}
 	if len(options.RuleSet) > 0 {
-		item := NewRuleSetItem(router, options.RuleSet, options.RuleSetIPCIDRMatchSource)
+		item := NewRuleSetItem(router, options.RuleSet, options.RuleSetIPCIDRMatchSource, options.RuleSetIPCIDRAcceptEmpty)
 		rule.items = append(rule.items, item)
 		rule.allItems = append(rule.allItems, item)
 	}

route/rule_item_cidr.go

@@ -75,18 +75,19 @@ func NewRawIPCIDRItem(isSource bool, ipSet *netipx.IPSet) *IPCIDRItem {
 func (r *IPCIDRItem) Match(metadata *adapter.InboundContext) bool {
 	if r.isSource || metadata.IPCIDRMatchSource {
 		return r.ipSet.Contains(metadata.Source.Addr)
-	} else {
-		if metadata.Destination.IsIP() {
-			return r.ipSet.Contains(metadata.Destination.Addr)
-		} else {
-			for _, address := range metadata.DestinationAddresses {
-				if r.ipSet.Contains(address) {
-					return true
-				}
+	}
+	if metadata.Destination.IsIP() {
+		return r.ipSet.Contains(metadata.Destination.Addr)
+	}
+	if len(metadata.DestinationAddresses) > 0 {
+		for _, address := range metadata.DestinationAddresses {
+			if r.ipSet.Contains(address) {
+				return true
 			}
 		}
+		return false
 	}
-	return false
+	return metadata.IPCIDRAcceptEmpty
 }
 
 func (r *IPCIDRItem) String() string {

route/rule_item_rule_set.go

@@ -15,14 +15,16 @@ type RuleSetItem struct {
 	router            adapter.Router
 	tagList           []string
 	setList           []adapter.RuleSet
-	ipcidrMatchSource bool
+	ipCidrMatchSource bool
+	ipCidrAcceptEmpty bool
 }
 
-func NewRuleSetItem(router adapter.Router, tagList []string, ipCIDRMatchSource bool) *RuleSetItem {
+func NewRuleSetItem(router adapter.Router, tagList []string, ipCIDRMatchSource bool, ipCidrAcceptEmpty bool) *RuleSetItem {
 	return &RuleSetItem{
 		router:            router,
 		tagList:           tagList,
-		ipcidrMatchSource: ipCIDRMatchSource,
+		ipCidrMatchSource: ipCIDRMatchSource,
+		ipCidrAcceptEmpty: ipCidrAcceptEmpty,
 	}
 }
 
@@ -39,7 +41,8 @@ func (r *RuleSetItem) Start() error {
 }
 
 func (r *RuleSetItem) Match(metadata *adapter.InboundContext) bool {
-	metadata.IPCIDRMatchSource = r.ipcidrMatchSource
+	metadata.IPCIDRMatchSource = r.ipCidrMatchSource
+	metadata.IPCIDRAcceptEmpty = r.ipCidrAcceptEmpty
 	for _, ruleSet := range r.setList {
 		if ruleSet.Match(metadata) {
 			return true
@@ -49,7 +52,7 @@ func (r *RuleSetItem) Match(metadata *adapter.InboundContext) bool {
 }
 
 func (r *RuleSetItem) ContainsDestinationIPCIDRRule() bool {
-	if r.ipcidrMatchSource {
+	if r.ipCidrMatchSource {
 		return false
 	}
 	return common.Any(r.setList, func(ruleSet adapter.RuleSet) bool {