external resolver

modules/zerogod/zerogod_save.go

@@ -3,10 +3,60 @@ package zerogod
 import (
 	"fmt"
 	"io/ioutil"
+	"strings"
 
+	"github.com/bettercap/bettercap/v2/zeroconf"
+	"github.com/evilsocket/islazy/str"
 	yaml "gopkg.in/yaml.v3"
 )
 
+type ServiceData struct {
+	Name      string   `yaml:"name"`                // Instance name (e.g. "My web page")
+	Service   string   `yaml:"service"`             // Service name (e.g. _http._tcp.)
+	Domain    string   `yaml:"domain"`              // If blank, assumes "local"
+	Port      int      `yaml:"port"`                // Service port
+	Records   []string `yaml:"records,omitempty"`   // Service DNS text records
+	Responder string   `yaml:"responder,omitempty"` // Optional IP to use instead of our tcp acceptor
+}
+
+func (svc ServiceData) FullName() string {
+	return fmt.Sprintf("%s.%s.%s",
+		strings.Trim(svc.Name, "."),
+		strings.Trim(svc.Service, "."),
+		strings.Trim(svc.Domain, "."))
+}
+
+func (svc ServiceData) Unregister() error {
+	if server, err := zeroconf.Register(svc.Name, svc.Service, svc.Domain, svc.Port, svc.Records, nil); err != nil {
+		return err
+	} else {
+		server.Shutdown()
+	}
+	return nil
+}
+
+func svcEntriesToData(services map[string]*zeroconf.ServiceEntry) []ServiceData {
+	data := make([]ServiceData, 0)
+	for _, svc := range services {
+		// filter out empty DNS records
+		records := ([]string)(nil)
+		for _, txt := range svc.Text {
+			if txt = str.Trim(txt); len(txt) > 0 {
+				records = append(records, txt)
+			}
+		}
+
+		data = append(data, ServiceData{
+			Name:    svc.Instance,
+			Service: svc.Service,
+			Domain:  svc.Domain,
+			Port:    svc.Port,
+			Records: records,
+		})
+	}
+	return data
+}
+
 func (mod *ZeroGod) save(address, filename string) error {
 	if address == "" {
 		return fmt.Errorf("address cannot be empty")
@@ -16,7 +66,8 @@ func (mod *ZeroGod) save(address, filename string) error {
 	}
 
 	if ipServices, found := mod.mapping[address]; found {
-		data, err := yaml.Marshal(ipServices)
+		services := svcEntriesToData(ipServices)
+		data, err := yaml.Marshal(services)
 		if err != nil {
 			return err
 		}
@@ -26,7 +77,7 @@ func (mod *ZeroGod) save(address, filename string) error {
 			return err
 		}
 
-		mod.Info("mDNS information saved to %s", filename)
+		mod.Info("zeroconf information saved to %s", filename)
 	} else {
 		return fmt.Errorf("no mDNS information found for address %s", address)
 	}