fix: system:// should ignore dns server setting by tun listener

listener/sing_tun/server.go

@@ -12,6 +12,7 @@ import (
 	"github.com/metacubex/mihomo/adapter/inbound"
 	"github.com/metacubex/mihomo/component/dialer"
 	"github.com/metacubex/mihomo/component/iface"
+	"github.com/metacubex/mihomo/component/resolver"
 	C "github.com/metacubex/mihomo/constant"
 	LC "github.com/metacubex/mihomo/listener/config"
 	"github.com/metacubex/mihomo/listener/sing"
@@ -39,6 +40,8 @@ type Listener struct {
 	networkUpdateMonitor    tun.NetworkUpdateMonitor
 	defaultInterfaceMonitor tun.DefaultInterfaceMonitor
 	packageManager          tun.PackageManager
+
+	dnsServerIp []string
 }
 
 func CalculateInterfaceName(name string) (tunName string) {
@@ -147,12 +150,16 @@ func New(options LC.Tun, tunnel C.Tunnel, additions ...inbound.Addition) (l *Lis
 
 		dnsAdds = append(dnsAdds, addrPort)
 	}
+
+	var dnsServerIp []string
 	for _, a := range options.Inet4Address {
 		addrPort := netip.AddrPortFrom(a.Addr().Next(), 53)
+		dnsServerIp = append(dnsServerIp, a.Addr().Next().String())
 		dnsAdds = append(dnsAdds, addrPort)
 	}
 	for _, a := range options.Inet6Address {
 		addrPort := netip.AddrPortFrom(a.Addr().Next(), 53)
+		dnsServerIp = append(dnsServerIp, a.Addr().Next().String())
 		dnsAdds = append(dnsAdds, addrPort)
 	}
 
@@ -244,6 +251,10 @@ func New(options LC.Tun, tunnel C.Tunnel, additions ...inbound.Addition) (l *Lis
 		return
 	}
 
+	l.dnsServerIp = dnsServerIp
+	// after tun.New sing-tun has set DNS to TUN interface
+	resolver.AddSystemDnsBlacklist(dnsServerIp...)
+
 	stackOptions := tun.StackOptions{
 		Context:                context.TODO(),
 		Tun:                    tunIf,
@@ -336,6 +347,7 @@ func parseRange(uidRanges []ranges.Range[uint32], rangeList []string) ([]ranges.
 
 func (l *Listener) Close() error {
 	l.closed = true
+	resolver.RemoveSystemDnsBlacklist(l.dnsServerIp...)
 	return common.Close(
 		l.tunStack,
 		l.tunIf,