Fix Docker instructions and add option to bind both UDP and TCP DNS l…

…isteners (#130)

Dockerfile

@@ -19,3 +19,4 @@ RUN apk --no-cache add ca-certificates && update-ca-certificates
 VOLUME ["/etc/acme-dns", "/var/lib/acme-dns"]
 ENTRYPOINT ["./acme-dns"]
 EXPOSE 53 80 443
+EXPOSE 53/udp

README.md

@@ -149,6 +149,7 @@ See the INSTALL section for information on how to do this.
 ```
 docker run --rm --name acmedns \
  -p 53:53 \
+ -p 53:53/udp \
  -p 80:80 \
  -v /path/to/your/config:/etc/acme-dns:ro \
  -v /path/to/your/data:/var/lib/acme-dns \
@@ -216,8 +217,8 @@ $ dig @auth.example.org d420c923-bbd7-4056-ab64-c3ca54c9b3cf.auth.example.org
 # In this case acme-dns will error out and you will need to define the listening interface
 # for example: listen = "127.0.0.1:53"
 listen = ":53"
-# protocol, "udp", "udp4", "udp6" or "tcp", "tcp4", "tcp6"
-protocol = "udp"
+# protocol, "both", "both4", "both6", "udp", "udp4", "udp6" or "tcp", "tcp4", "tcp6"
+protocol = "both"
 # domain name to serve the requests off of
 domain = "auth.example.org"
 # zone name server
@@ -300,6 +301,10 @@ logformat = "text"
 
 
 ## Changelog
+
+- master
+ - Changed
+ - A new protocol selection for DNS server "both", that binds both - UDP and TCP ports.
 - v0.6
  - New
  - Command line flag `-c` to specify location of config file.

config.cfg

@@ -2,9 +2,9 @@
 # DNS interface. Note that systemd-resolved may reserve port 53 on 127.0.0.53
 # In this case acme-dns will error out and you will need to define the listening interface
 # for example: listen = "127.0.0.1:53"
-listen = ":53"
-# protocol, "udp", "udp4", "udp6" or "tcp", "tcp4", "tcp6"
-protocol = "udp"
+listen = "127.0.0.1:53"
+# protocol, "both", "both4", "both6", "udp", "udp4", "udp6" or "tcp", "tcp4", "tcp6"
+protocol = "both"
 # domain name to serve the requests off of
 domain = "auth.example.org"
 # zone name server
@@ -26,7 +26,8 @@ debug = false
 engine = "sqlite3"
 # Connection string, filename for sqlite3 and postgres:https://$username:$password@$host/$db_name for postgres
 # Please note that the default Docker image uses path /var/lib/acme-dns/acme-dns.db for sqlite3
-connection = "/var/lib/acme-dns/acme-dns.db"
+#connection = "/var/lib/acme-dns/acme-dns.db"
+connection = "acme-dns.db"
 # connection = "postgres:https://user:password@localhost/acmedns_db"
 
 [api]

docker-compose.yml

@@ -8,6 +8,7 @@ services:
  ports:
  - "443:443"
  - "53:53"
+ - "53:53/udp"
  - "80:80"
  volumes:
  - ./config:/etc/acme-dns:ro

main.go

@@ -8,6 +8,7 @@ import (
  stdlog "log"
  "net/http"
  "os"
+ "strings"
  "syscall"
 
  "github.com/julienschmidt/httprouter"
@@ -60,8 +61,25 @@ func main() {
  errChan := make(chan error, 1)
 
  // DNS server
- dnsServer := setupDNSServer()
- go startDNS(dnsServer, errChan)
+ if strings.HasPrefix(Config.General.Proto, "both") {
+ // Handle the case where DNS server should be started for both udp and tcp
+ udpProto := "udp"
+ tcpProto := "tcp"
+ if strings.HasSuffix(Config.General.Proto, "4") {
+ udpProto += "4"
+ tcpProto += "4"
+ } else if strings.HasSuffix(Config.General.Proto, "6") {
+ udpProto += "6"
+ tcpProto += "6"
+ }
+ dnsServerUDP := setupDNSServer(udpProto)
+ dnsServerTCP := setupDNSServer(tcpProto)
+ go startDNS(dnsServerUDP, errChan)
+ go startDNS(dnsServerTCP, errChan)
+ } else {
+ dnsServer := setupDNSServer(Config.General.Proto)
+ go startDNS(dnsServer, errChan)
+ }
 
  // HTTP API
  go startHTTPAPI(errChan)
@@ -79,15 +97,15 @@ func main() {
 func startDNS(server *dns.Server, errChan chan error) {
  // DNS server part
  dns.HandleFunc(".", handleRequest)
- log.WithFields(log.Fields{"addr": Config.General.Listen}).Info("Listening DNS")
+ log.WithFields(log.Fields{"addr": Config.General.Listen, "proto": server.Net}).Info("Listening DNS")
  err := server.ListenAndServe()
  if err != nil {
  errChan <- err
  }
 }
 
-func setupDNSServer() *dns.Server {
- return &dns.Server{Addr: Config.General.Listen, Net: Config.General.Proto}
+func setupDNSServer(proto string) *dns.Server {
+ return &dns.Server{Addr: Config.General.Listen, Net: proto}
 }
 
 func startHTTPAPI(errChan chan error) {

main_test.go

@@ -43,7 +43,7 @@ func TestMain(m *testing.M) {
  _ = newDb.Init("sqlite3", ":memory:")
  }
  DB = newDb
- server := setupDNSServer()
+ server := setupDNSServer("udp")
  // Make sure that we're not creating a race condition in tests
  var wg sync.WaitGroup
  wg.Add(1)