1 files changed, 179 insertions, 0 deletions
diff --git a/src/main/java/de/thedevstack/conversationsplus/utils/DNSHelper.java b/src/main/java/de/thedevstack/conversationsplus/utils/DNSHelper.java
new file mode 100644
index 00000000..8951426f
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/utils/DNSHelper.java
@@ -0,0 +1,179 @@
+package de.thedevstack.conversationsplus.utils;
+
+import de.measite.minidns.Client;
+import de.measite.minidns.DNSMessage;
+import de.measite.minidns.Record;
+import de.measite.minidns.Record.TYPE;
+import de.measite.minidns.Record.CLASS;
+import de.measite.minidns.record.SRV;
+import de.measite.minidns.record.A;
+import de.measite.minidns.record.AAAA;
+import de.measite.minidns.record.Data;
+import de.measite.minidns.util.NameUtil;
+import de.thedevstack.conversationsplus.Config;
+import de.thedevstack.conversationsplus.xmpp.jid.Jid;
+
+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.SocketTimeoutException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Random;
+import java.util.TreeMap;
+import java.util.regex.Pattern;
+
+import android.os.Bundle;
+import android.util.Log;
+
+public class DNSHelper {
+
+	public static final Pattern PATTERN_IPV4 = Pattern.compile("\\A(25[0-5]|2[0-4]\\d|[0-1]?\\d?\\d)(\\.(25[0-5]|2[0-4]\\d|[0-1]?\\d?\\d)){3}\\z");
+	public static final Pattern PATTERN_IPV6_HEX4DECCOMPRESSED = Pattern.compile("\\A((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?) ::((?:[0-9A-Fa-f]{1,4}:)*)(25[0-5]|2[0-4]\\d|[0-1]?\\d?\\d)(\\.(25[0-5]|2[0-4]\\d|[0-1]?\\d?\\d)){3}\\z");
+	public static final Pattern PATTERN_IPV6_6HEX4DEC = Pattern.compile("\\A((?:[0-9A-Fa-f]{1,4}:){6,6})(25[0-5]|2[0-4]\\d|[0-1]?\\d?\\d)(\\.(25[0-5]|2[0-4]\\d|[0-1]?\\d?\\d)){3}\\z");
+	public static final Pattern PATTERN_IPV6_HEXCOMPRESSED = Pattern.compile("\\A((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?)::((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?)\\z");
+	public static final Pattern PATTERN_IPV6 = Pattern.compile("\\A(?:[0-9a-fA-F]{1,4}:){7}[0-9a-fA-F]{1,4}\\z");
+
+	protected static Client client = new Client();
+
+	public static Bundle getSRVRecord(final Jid jid) throws IOException {
+        final String host = jid.getDomainpart();
+		String dns[] = client.findDNS();
+
+		if (dns != null) {
+			for (String dnsserver : dns) {
+				InetAddress ip = InetAddress.getByName(dnsserver);
+				Bundle b = queryDNS(host, ip);
+				if (b.containsKey("values")) {
+					return b;
+				}
+			}
+		}
+		return queryDNS(host, InetAddress.getByName("8.8.8.8"));
+	}
+
+	public static Bundle queryDNS(String host, InetAddress dnsServer) {
+		Bundle bundle = new Bundle();
+		try {
+			String qname = "_xmpp-client._tcp." + host;
+			Log.d(Config.LOGTAG, "using dns server: " + dnsServer.getHostAddress() + " to look up " + host);
+			DNSMessage message = client.query(qname, TYPE.SRV, CLASS.IN, dnsServer.getHostAddress());
+
+			TreeMap<Integer, ArrayList<SRV>> priorities = new TreeMap<>();
+			TreeMap<String, ArrayList<String>> ips4 = new TreeMap<>();
+			TreeMap<String, ArrayList<String>> ips6 = new TreeMap<>();
+
+			for (Record[] rrset : new Record[][] { message.getAnswers(), message.getAdditionalResourceRecords() }) {
+				for (Record rr : rrset) {
+					Data d = rr.getPayload();
+					if (d instanceof SRV && NameUtil.idnEquals(qname, rr.getName())) {
+						SRV srv = (SRV) d;
+						if (!priorities.containsKey(srv.getPriority())) {
+							priorities.put(srv.getPriority(),new ArrayList<SRV>());
+						}
+						priorities.get(srv.getPriority()).add(srv);
+					}
+					if (d instanceof A) {
+						A a = (A) d;
+						if (!ips4.containsKey(rr.getName())) {
+							ips4.put(rr.getName(), new ArrayList<String>());
+						}
+						ips4.get(rr.getName()).add(a.toString());
+					}
+					if (d instanceof AAAA) {
+						AAAA aaaa = (AAAA) d;
+						if (!ips6.containsKey(rr.getName())) {
+							ips6.put(rr.getName(), new ArrayList<String>());
+						}
+						ips6.get(rr.getName()).add("[" + aaaa.toString() + "]");
+					}
+				}
+			}
+
+			ArrayList<SRV> result = new ArrayList<>();
+			for (ArrayList<SRV> s : priorities.values()) {
+				result.addAll(s);
+			}
+
+			ArrayList<Bundle> values = new ArrayList<>();
+			if (result.size() == 0) {
+				DNSMessage response;
+				response = client.query(host, TYPE.A, CLASS.IN, dnsServer.getHostAddress());
+				for(int i = 0; i < response.getAnswers().length; ++i) {
+					values.add(createNamePortBundle(host,5222,response.getAnswers()[i].getPayload()));
+				}
+				response = client.query(host, TYPE.AAAA, CLASS.IN, dnsServer.getHostAddress());
+				for(int i = 0; i < response.getAnswers().length; ++i) {
+					values.add(createNamePortBundle(host,5222,response.getAnswers()[i].getPayload()));
+				}
+				values.add(createNamePortBundle(host,5222));
+				bundle.putParcelableArrayList("values", values);
+				return bundle;
+			}
+			for (SRV srv : result) {
+				if (ips6.containsKey(srv.getName())) {
+					values.add(createNamePortBundle(srv.getName(),srv.getPort(),ips6));
+				} else {
+					DNSMessage response = client.query(srv.getName(), TYPE.AAAA, CLASS.IN, dnsServer.getHostAddress());
+					for(int i = 0; i < response.getAnswers().length; ++i) {
+						values.add(createNamePortBundle(srv.getName(),srv.getPort(),response.getAnswers()[i].getPayload()));
+					}
+				}
+				if (ips4.containsKey(srv.getName())) {
+					values.add(createNamePortBundle(srv.getName(),srv.getPort(),ips4));
+				} else {
+					DNSMessage response = client.query(srv.getName(), TYPE.A, CLASS.IN, dnsServer.getHostAddress());
+					for(int i = 0; i < response.getAnswers().length; ++i) {
+						values.add(createNamePortBundle(srv.getName(),srv.getPort(),response.getAnswers()[i].getPayload()));
+					}
+				}
+				values.add(createNamePortBundle(srv.getName(), srv.getPort()));
+			}
+			bundle.putParcelableArrayList("values", values);
+		} catch (SocketTimeoutException e) {
+			bundle.putString("error", "timeout");
+		} catch (Exception e) {
+			e.printStackTrace();
+			bundle.putString("error", "unhandled");
+		}
+		return bundle;
+	}
+
+	private static Bundle createNamePortBundle(String name, int port) {
+		Bundle namePort = new Bundle();
+		namePort.putString("name", name);
+		namePort.putInt("port", port);
+		return namePort;
+	}
+
+	private static Bundle createNamePortBundle(String name, int port, TreeMap<String, ArrayList<String>> ips) {
+		Bundle namePort = new Bundle();
+		namePort.putString("name", name);
+		namePort.putInt("port", port);
+		if (ips!=null) {
+			ArrayList<String> ip = ips.get(name);
+			Collections.shuffle(ip, new Random());
+			namePort.putString("ip", ip.get(0));
+		}
+		return namePort;
+	}
+
+	private static Bundle createNamePortBundle(String name, int port, Data data) {
+		Bundle namePort = new Bundle();
+		namePort.putString("name", name);
+		namePort.putInt("port", port);
+		if (data instanceof A) {
+			namePort.putString("ip", data.toString());
+		} else if (data instanceof AAAA) {
+			namePort.putString("ip","["+data.toString()+"]");
+		}
+		return namePort;
+	}
+
+	public static boolean isIp(final String server) {
+		return PATTERN_IPV4.matcher(server).matches()
+				|| PATTERN_IPV6.matcher(server).matches()
+				|| PATTERN_IPV6_6HEX4DEC.matcher(server).matches()
+				|| PATTERN_IPV6_HEX4DECCOMPRESSED.matcher(server).matches()
+				|| PATTERN_IPV6_HEXCOMPRESSED.matcher(server).matches();
+	}
+}