Refactored Dns classes and added initial implementation of a MDNS Server

src/zutil/net/dns/DnsResolutionListener.java

@@ -24,6 +24,8 @@
 package zutil.net.dns;
 
 
+import zutil.net.dns.packet.DnsPacket;
+
 public interface DnsResolutionListener {
         void receivedResponse(DnsPacket packet);
     }

src/zutil/net/dns/DnsService.java

@@ -0,0 +1,16 @@
+package zutil.net.dns;
+
+import java.net.InetAddress;
+import java.util.HashMap;
+
+/**
+ * This class contains data about a service that
+ * can be looked up through DNS and MDNS.
+ */
+public class DnsService {
+
+    private String name;
+    private String dns;
+    private InetAddress host;
+    private HashMap properties;
+}

src/zutil/net/dns/MulticastDnsClient.java

@@ -26,6 +26,9 @@ package zutil.net.dns;
 
 import zutil.io.MultiPrintStream;
 import zutil.log.LogUtil;
+import zutil.net.dns.packet.DnsConstants;
+import zutil.net.dns.packet.DnsPacket;
+import zutil.net.dns.packet.DnsPacketQuestion;
 import zutil.net.threaded.ThreadedUDPNetwork;
 import zutil.net.threaded.ThreadedUDPNetworkThread;
 import zutil.parser.binary.BinaryStructInputStream;
@@ -40,9 +43,12 @@ import java.util.HashSet;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import static zutil.net.dns.MulticastDnsServer.MDNS_MULTICAST_ADDR;
+import static zutil.net.dns.MulticastDnsServer.MDNS_MULTICAST_PORT;
+
 /**
  * This class implements a MDNS Client. MDNS is a version
- * of the DNS protocol but used a Zeroconf application.
+ * of the DNS protocol but supports Zeroconf.
  *
  * @see <a href="http://tools.ietf.org/html/rfc1035">DNS Spec (rfc1035)</a>
  * @see <a href="https://tools.ietf.org/html/rfc6763">DNS-SD Spec (rfc6763)</a>
@@ -51,9 +57,6 @@ import java.util.logging.Logger;
 public class MulticastDnsClient extends ThreadedUDPNetwork implements ThreadedUDPNetworkThread{
     private static final Logger logger = LogUtil.getLogger();
 
-    private static final String MDNS_MULTICAST_ADDR = "224.0.0.251";
-    private static final int    MDNS_MULTICAST_PORT = 5353;
-
 
     private HashSet<Integer> activeProbes;
     private DnsResolutionListener listener;

src/zutil/net/dns/MulticastDnsServer.java

@@ -0,0 +1,119 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2015 Ziver Koc
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package zutil.net.dns;
+
+import zutil.log.LogUtil;
+import zutil.net.dns.packet.DnsPacket;
+import zutil.net.dns.packet.DnsPacketQuestion;
+import zutil.net.dns.packet.DnsPacketResource;
+import zutil.net.threaded.ThreadedUDPNetwork;
+import zutil.net.threaded.ThreadedUDPNetworkThread;
+import zutil.parser.binary.BinaryStructInputStream;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.net.DatagramPacket;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+/**
+ * This class implements a MDNS Server. MDNS is a version
+ * of the DNS protocol but supports Zeroconf.
+ *
+ * @see <a href="http://tools.ietf.org/html/rfc1035">DNS Spec (rfc1035)</a>
+ * @see <a href="https://tools.ietf.org/html/rfc6763">DNS-SD Spec (rfc6763)</a>
+ * @author Ziver
+ */
+public class MulticastDnsServer extends ThreadedUDPNetwork implements ThreadedUDPNetworkThread{
+    private static final Logger logger = LogUtil.getLogger();
+
+    protected static final String MDNS_MULTICAST_ADDR = "224.0.0.251";
+    protected static final int    MDNS_MULTICAST_PORT = 5353;
+
+
+    private HashMap<String,ArrayList> entries = new HashMap<>();
+
+
+
+    public MulticastDnsServer() throws IOException {
+        super(MDNS_MULTICAST_ADDR, MDNS_MULTICAST_PORT);
+        setThread( this );
+
+    }
+
+
+    /**
+     * Add a domain name specific data that will be returned to a requesting client
+     *
+     * @param   name    is the domain name to add the entry under
+     * @param   type    {@link zutil.net.dns.packet.DnsConstants.TYPE}
+     * @param   clazz   {@link zutil.net.dns.packet.DnsConstants.CLASS}
+     * @param   data
+     */
+    public void addEntry(String name, int type, int clazz, String data){
+        DnsPacketResource resource = new DnsPacketResource();
+        resource.name = name;
+        resource.type = type;
+        resource.clazz = clazz;
+        //resource.ttl = 10; ???
+        resource.length = data.length();
+        resource.data = data;
+
+        addEntry(resource);
+    }
+
+    private void addEntry(DnsPacketResource resource) {
+        if ( ! entries.containsKey(resource.name))
+            entries.put(resource.name, new ArrayList());
+        entries.get(resource.name).add(resource);
+    }
+
+
+
+    @Override
+    public void receivedPacket(DatagramPacket packet, ThreadedUDPNetwork network) {
+        try {
+            ByteArrayInputStream buffer = new ByteArrayInputStream(packet.getData(),
+                    packet.getOffset(), packet.getLength());
+            BinaryStructInputStream in = new BinaryStructInputStream(buffer);
+            DnsPacket dnsPacket = DnsPacket.read(in);
+
+            // Just handle queries and no responses
+            if ( ! dnsPacket.getHeader().flagQueryResponse){
+                for (DnsPacketQuestion question : dnsPacket.getQuestions()){
+                    if (entries.containsKey(question.name)){
+                        // Respond with entries
+
+                    }
+                }
+            }
+        } catch (IOException e){
+            logger.log(Level.WARNING, null, e);
+        }
+    }
+
+}

src/zutil/net/dns/packet/DnsConstants.java

@@ -1,4 +1,4 @@
-package zutil.net.dns;
+package zutil.net.dns.packet;
 
 /**
  *

src/zutil/net/dns/packet/DnsPacket.java

@@ -1,4 +1,4 @@
-package zutil.net.dns;
+package zutil.net.dns.packet;
 
 import zutil.parser.binary.BinaryStructInputStream;
 import zutil.parser.binary.BinaryStructOutputStream;

src/zutil/net/dns/packet/DnsPacketHeader.java

@@ -22,7 +22,7 @@
  * THE SOFTWARE.
  */
 
-package zutil.net.dns;
+package zutil.net.dns.packet;
 
 import zutil.parser.binary.BinaryStruct;
 

src/zutil/net/dns/packet/DnsPacketQuestion.java

@@ -22,16 +22,10 @@
  * THE SOFTWARE.
  */
 
-package zutil.net.dns;
+package zutil.net.dns.packet;
 
-import zutil.parser.binary.BinaryFieldData;
-import zutil.parser.binary.BinaryFieldSerializer;
 import zutil.parser.binary.BinaryStruct;
 
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.OutputStream;
-
 /**
  * @see <a href="http://tools.ietf.org/html/rfc1035">DNS Spec (rfc1035)</a>
  * @author Ziver
@@ -96,44 +90,4 @@ public class DnsPacketQuestion implements BinaryStruct {
     }
 
 
-
-
-
-    public static class FQDNStringSerializer implements BinaryFieldSerializer<String> {
-
-        public String read(InputStream in, BinaryFieldData field) throws IOException {
-            StringBuilder str = new StringBuilder();
-            int c = in.read();
-            // Is this a pointer
-            if ((c & 0b1100_0000) == 0b1100_0000 ){
-                int offset = (c & 0b0011_1111) << 8;
-                offset |= in.read() & 0b1111_1111;
-                str.append(offset);
-            }
-            // Normal Domain String
-            else {
-                while (c > 0) {
-                    for (int i = 0; i < c; ++i) {
-                        str.append((char) in.read());
-                    }
-                    c = in.read();
-                    if (c > 0)
-                        str.append('.');
-                }
-            }
-            return str.toString();
-        }
-
-        public void write(OutputStream out, String domain, BinaryFieldData field) throws IOException {
-            if (domain != null){
-                String[] labels = domain.split("\\.");
-                for (String label : labels) {
-                    out.write(label.length());
-                    out.write(label.getBytes());
-                }
-            }
-            out.write(0);
-        }
-
-    }
 }

src/zutil/net/dns/packet/DnsPacketResource.java

@@ -22,7 +22,7 @@
  * THE SOFTWARE.
  */
 
-package zutil.net.dns;
+package zutil.net.dns.packet;
 
 import zutil.parser.binary.BinaryStruct;
 
@@ -65,7 +65,7 @@ public class DnsPacketResource implements BinaryStruct {
     /**
      * a domain name to which this resource record pertains.
      */
-    @CustomBinaryField(index=10, serializer=DnsPacketQuestion.FQDNStringSerializer.class)
+    @CustomBinaryField(index=10, serializer=FQDNStringSerializer.class)
     public String name;
 
     /**

src/zutil/net/dns/packet/FQDNStringSerializer.java

@@ -0,0 +1,49 @@
+package zutil.net.dns.packet;
+
+import zutil.parser.binary.BinaryFieldData;
+import zutil.parser.binary.BinaryFieldSerializer;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+/**
+ * A serializer class that can read and write a DNS FQDN in binary format.
+ */
+public class FQDNStringSerializer implements BinaryFieldSerializer<String> {
+
+    public String read(InputStream in, BinaryFieldData field) throws IOException {
+        StringBuilder str = new StringBuilder();
+        int c = in.read();
+        // Is this a pointer
+        if ((c & 0b1100_0000) == 0b1100_0000) {
+            int offset = (c & 0b0011_1111) << 8;
+            offset |= in.read() & 0b1111_1111;
+            str.append(offset);
+        }
+        // Normal Domain String
+        else {
+            while (c > 0) {
+                for (int i = 0; i < c; ++i) {
+                    str.append((char) in.read());
+                }
+                c = in.read();
+                if (c > 0)
+                    str.append('.');
+            }
+        }
+        return str.toString();
+    }
+
+    public void write(OutputStream out, String domain, BinaryFieldData field) throws IOException {
+        if (domain != null) {
+            String[] labels = domain.split("\\.");
+            for (String label : labels) {
+                out.write(label.length());
+                out.write(label.getBytes());
+            }
+        }
+        out.write(0);
+    }
+
+}

test/zutil/net/dns/DnsPacketTest.java

@@ -26,6 +26,7 @@ package zutil.net.dns;
 
 import org.junit.Test;
 import zutil.converter.Converter;
+import zutil.net.dns.packet.*;
 import zutil.parser.binary.BinaryStructInputStream;
 import zutil.parser.binary.BinaryStructOutputStream;
 

test/zutil/net/dns/MulticastDnsClientTest.java

@@ -3,6 +3,7 @@ package zutil.net.dns;
 import zutil.io.MultiPrintStream;
 import zutil.log.CompactLogFormatter;
 import zutil.log.LogUtil;
+import zutil.net.dns.packet.DnsPacket;
 
 import java.io.IOException;
 import java.util.logging.Level;