Always sent a txt, it's required

faceless2 · May 20, 2024 · df12177 · df12177
1 parent b37dc02
commit df12177
Show file tree

Hide file tree

Showing 3 changed files with 20 additions and 13 deletions.
diff --git a/src/main/com/bfo/zeroconf/Packet.java b/src/main/com/bfo/zeroconf/Packet.java
@@ -59,9 +59,7 @@ public class Packet {
         List<Record> additionals = new ArrayList<Record>();
         answers.add(Record.newPtr(domain, fqdn));
         answers.add(Record.newSrv(fqdn, service.getHost(), service.getPort(), 0, 0));
-        if (!service.getText().isEmpty()) {
-            additionals.add(Record.newTxt(fqdn, service.getText()));
-        }
+        answers.add(Record.newTxt(fqdn, service.getText()));    // Seems "txt" is always required
         for (InetAddress address : service.getAddresses()) {
             additionals.add(Record.newAddress(service.getHost(), address));
         }

diff --git a/src/main/com/bfo/zeroconf/Record.java b/src/main/com/bfo/zeroconf/Record.java
@@ -132,18 +132,18 @@ static Record newPtr(String name, String value) {
         if (name == null || value == null) {
             throw new IllegalArgumentException("name or value is null");
         }
-        return new Record(TYPE_PTR, CLAZZ, 28800, name, value);
+        return new Record(TYPE_PTR, 1, 4500, name, value);
     }
 
     static Record newSrv(String name, String host, int port, int weight, int priority) {
-        if (name == null || host == null || port < 1 || port > 65535) {
+        if (name == null || host == null || port < 0 || port > 65535) {
             throw new IllegalArgumentException("name, host or port is invalid");
         }
         return new Record(TYPE_SRV, CLAZZ, 120, name, new SrvData(priority, weight, port, host));
     }
 
     static Record newTxt(String name, Map<String,String> map) {
-        if (name == null || map == null || map.isEmpty()) {
+        if (name == null || map == null) {
             throw new IllegalArgumentException("name or map is invalid");
         }
         return new Record(TYPE_TXT, CLAZZ, 4500, name, map);
@@ -239,11 +239,15 @@ void write(ByteBuffer out) {
             } else if (type == TYPE_AAAA) {
                 out.put(((Inet6Address)getAddress()).getAddress());
             } else if (type == TYPE_TXT) {
-                for (Map.Entry<String,String> e : getText().entrySet()) {
-                    String value = e.getKey()+"="+e.getValue();
-                    byte[] b = value.getBytes(StandardCharsets.UTF_8);
-                    out.put((byte)b.length);
-                    out.put(b);
+                if (getText().isEmpty()) {
+                    out.put((byte)0);
+                } else {
+                    for (Map.Entry<String,String> e : getText().entrySet()) {
+                        String value = e.getKey()+"="+e.getValue();
+                        byte[] b = value.getBytes(StandardCharsets.UTF_8);
+                        out.put((byte)b.length);
+                        out.put(b);
+                    }
                 }
             } else if (data instanceof byte[]) {
                 out.put((byte[])data);

diff --git a/src/main/com/bfo/zeroconf/Zeroconf.java b/src/main/com/bfo/zeroconf/Zeroconf.java
@@ -331,6 +331,7 @@ public void query(String type, String name) {
     //--------------------------------------------------------------------
 
     void send(Packet packet) {
+        // System.out.println("# TX " + packet);
         thread.push(packet);
     }
 
@@ -669,6 +670,7 @@ public void run() {
                         if (address != null && buf.position() != 0) {
                             buf.flip();
                             packet = new Packet(buf, address);
+                            // System.out.println("# RX: " + packet);
                             processPacket(packet);
                         }
                     }
@@ -803,14 +805,17 @@ private void processQuestions(Packet packet) {
                                 additionals = new ArrayList<Record>();
                             }
                             answers.add(answer);
+                            List<Record> l = new ArrayList<Record>();
+                            l.addAll(p.getAnswers());
+                            l.addAll(p.getAdditionals());
                             if (answer.getType() == Record.TYPE_PTR && question.getType() != Record.TYPE_ANY) {
                                 // When including a DNS-SD Service Instance Enumeration or Selective
                                 // Instance Enumeration (subtype) PTR record in a response packet, the
                                 // server/responder SHOULD include the following additional records:
                                 // * The SRV record(s) named in the PTR rdata.
                                 // * The TXT record(s) named in the PTR rdata.
                                 // * All address records (type "A" and "AAAA") named in the SRV rdata.
-                                for (Record a : p.getAnswers()) {
+                                for (Record a : l) {
                                     if (a.getType() == Record.TYPE_SRV || a.getType() == Record.TYPE_A || a.getType() == Record.TYPE_AAAA || a.getType() == Record.TYPE_TXT) {
                                         additionals.add(a);
                                     }
@@ -819,7 +824,7 @@ private void processQuestions(Packet packet) {
                                 // When including an SRV record in a response packet, the
                                 // server/responder SHOULD include the following additional records:
                                 // * All address records (type "A" and "AAAA") named in the SRV rdata.
-                                for (Record a : p.getAnswers()) {
+                                for (Record a : l) {
                                     if (a.getType() == Record.TYPE_A || a.getType() == Record.TYPE_AAAA || a.getType() == Record.TYPE_TXT) {
                                         additionals.add(a);
                                     }