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package eu.siacs.conversations.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 eu.siacs.conversations.Config;
import eu.siacs.conversations.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 android.os.Bundle;
import android.util.Log;
public class DNSHelper {
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()));
}
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) {
Log.d(Config.LOGTAG,e.getMessage());
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;
}
final protected static char[] hexArray = "0123456789ABCDEF".toCharArray();
public static String bytesToHex(byte[] bytes) {
char[] hexChars = new char[bytes.length * 2];
for (int j = 0; j < bytes.length; j++) {
int v = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[v >>> 4];
hexChars[j * 2 + 1] = hexArray[v & 0x0F];
}
return new String(hexChars);
}
}
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