feat: add support for specifying real-ip-filter in DNS

component/fakeip/pool.go

@@ -29,16 +29,17 @@ type store interface {
 
 // Pool is an implementation about fake ip generator without storage
 type Pool struct {
-	gateway netip.Addr
-	first   netip.Addr
-	last    netip.Addr
-	offset  netip.Addr
-	cycle   bool
-	mux     sync.Mutex
-	host    []C.DomainMatcher
-	mode    C.FilterMode
-	ipnet   netip.Prefix
-	store   store
+	gateway  netip.Addr
+	first    netip.Addr
+	last     netip.Addr
+	offset   netip.Addr
+	cycle    bool
+	mux      sync.Mutex
+	host     []C.DomainMatcher
+	realhost []C.DomainMatcher
+	mode     C.FilterMode
+	ipnet    netip.Prefix
+	store    store
 }
 
 // Lookup return a fake ip with host
@@ -75,12 +76,22 @@ func (p *Pool) ShouldSkipped(domain string) bool {
 }
 
 func (p *Pool) shouldSkipped(domain string) bool {
+	// When both fake-ip-filter and real-ip-filter match, the fake-ip-filter takes precedence.
+	// If neither filter matches, fake-ip is returned.
+	// For example:
+	//     If an ad domain (www.ad.com) matches both fake-ip-filter:AD and real-ip-filter:cn, fake-ip will be returned.
+	//     If a blocked domain (wiki.metacubex.one) does not match either filter, fake-ip will be returned by default.
 	for _, matcher := range p.host {
 		if matcher.MatchDomain(domain) {
 			return true
 		}
 	}
-	return false
+	for _, matcher := range p.realhost {
+		if matcher.MatchDomain(domain) {
+			return false
+		}
+	}
+	return true
 }
 
 // Exist returns if given ip exists in fake-ip pool
@@ -164,9 +175,10 @@ func (p *Pool) restoreState() {
 }
 
 type Options struct {
-	IPNet netip.Prefix
-	Host  []C.DomainMatcher
-	Mode  C.FilterMode
+	IPNet    netip.Prefix
+	Host     []C.DomainMatcher
+	RealHost []C.DomainMatcher
+	Mode     C.FilterMode
 
 	// Size sets the maximum number of entries in memory
 	// and does not work if Persistence is true
@@ -191,14 +203,15 @@ func New(options Options) (*Pool, error) {
 	}
 
 	pool := &Pool{
-		gateway: gateway,
-		first:   first,
-		last:    last,
-		offset:  first.Prev(),
-		cycle:   false,
-		host:    options.Host,
-		mode:    options.Mode,
-		ipnet:   options.IPNet,
+		gateway:  gateway,
+		first:    first,
+		last:     last,
+		offset:   first.Prev(),
+		cycle:    false,
+		host:     options.Host,
+		realhost: options.RealHost,
+		mode:     options.Mode,
+		ipnet:    options.IPNet,
 	}
 	if options.Persistence {
 		pool.store = newCachefileStore(cachefile.Cache())

config/config.go

@@ -206,6 +206,7 @@ type RawDNS struct {
 	EnhancedMode          C.DNSMode                           `yaml:"enhanced-mode" json:"enhanced-mode"`
 	FakeIPRange           string                              `yaml:"fake-ip-range" json:"fake-ip-range"`
 	FakeIPFilter          []string                            `yaml:"fake-ip-filter" json:"fake-ip-filter"`
+	RealIPFilter          []string                            `yaml:"real-ip-filter" json:"real-ip-filter"`
 	FakeIPFilterMode      C.FilterMode                        `yaml:"fake-ip-filter-mode" json:"fake-ip-filter-mode"`
 	DefaultNameserver     []string                            `yaml:"default-nameserver" json:"default-nameserver"`
 	CacheAlgorithm        string                              `yaml:"cache-algorithm" json:"cache-algorithm"`
@@ -1449,10 +1450,17 @@ func parseDNS(rawCfg *RawConfig, hosts *trie.DomainTrie[resolver.HostValue], rul
 			return nil, err
 		}
 
+		// real ip via host rule
+		realHost, err := parseDomain(cfg.RealIPFilter, fakeIPTrie, "dns.real-ip-filter", ruleProviders)
+		if err != nil {
+			return nil, err
+		}
+
 		pool, err := fakeip.New(fakeip.Options{
 			IPNet:       fakeIPRange,
 			Size:        1000,
 			Host:        host,
+			RealHost:    realHost,
 			Mode:        cfg.FakeIPFilterMode,
 			Persistence: rawCfg.Profile.StoreFakeIP,
 		})

docs/config.yaml

@@ -257,6 +257,20 @@ dns:
   # 可设置为whitelist，即只有匹配成功才返回fake-ip
   fake-ip-filter-mode: blacklist
 
+  # fake-ip 白名单模式
+  # 当 fake-ip-filter 和 real-ip-filter 同时匹配时，fake-ip-filter 优先级更高。
+  # 如果都没有匹配到规则，则返回 fake-ip。
+  # 例如：
+  #     如果广告域名 (www.ad.com) 同时满足 fake-ip-filter:AD 和 real-ip-filter:cn，则返回 fake-ip。
+  #     如果被墙域名 (wiki.metacubex.one) 都没匹配到，默认返回 fake-ip。
+  #  fake-ip-filter-mode: whitelist
+  #  fake-ip-filter:
+  #    - rule-set:anti-AD
+  #    - geosite:gfw
+  #  real-ip-filter:
+  #    - geosite:cn
+  #    - rule-set:douyin
+
   # use-hosts: true # 查询 hosts
 
   # 配置后面的nameserver、fallback和nameserver-policy向dns服务器的连接过程是否遵守遵守rules规则