@@ -0,0 +1,92 @@
+/*
+ * Copyright 2015-2016 the original author or authors
+ *
+ * This software is licensed under the Apache License, Version 2.0,
+ * the GNU Lesser General Public License version 2 or later ("LGPL")
+ * and the WTFPL.
+ * You may choose either license to govern your use of this software only
+ * upon the condition that you accept all of the terms of either
+ * the Apache License 2.0, the LGPL 2.1+ or the WTFPL.
+ */
+package eu.siacs.conversations.utils;
+
+
+import de.measite.minidns.dnsserverlookup.AbstractDNSServerLookupMechanism;
+import de.measite.minidns.dnsserverlookup.AndroidUsingReflection;
+import de.measite.minidns.dnsserverlookup.DNSServerLookupMechanism;
+import de.measite.minidns.util.PlatformDetection;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.LineNumberReader;
+import java.net.InetAddress;
+import java.util.HashSet;
+import java.util.logging.Level;
+
+/**
+ * Try to retrieve the list of DNS server by executing getprop.
+ */
+public class AndroidUsingExecLowPriority extends AbstractDNSServerLookupMechanism {
+
+ public static final DNSServerLookupMechanism INSTANCE = new AndroidUsingExecLowPriority();
+ public static final int PRIORITY = AndroidUsingReflection.PRIORITY + 1;
+
+ private AndroidUsingExecLowPriority() {
+ super(AndroidUsingExecLowPriority.class.getSimpleName(), PRIORITY);
+ }
+
+ @Override
+ public String[] getDnsServerAddresses() {
+ try {
+ Process process = Runtime.getRuntime().exec("getprop");
+ InputStream inputStream = process.getInputStream();
+ LineNumberReader lnr = new LineNumberReader(
+ new InputStreamReader(inputStream));
+ String line;
+ HashSet<String> server = new HashSet<>(6);
+ while ((line = lnr.readLine()) != null) {
+ int split = line.indexOf("]: [");
+ if (split == -1) {
+ continue;
+ }
+ String property = line.substring(1, split);
+ String value = line.substring(split + 4, line.length() - 1);
+
+ if (value.isEmpty()) {
+ continue;
+ }
+
+ if (property.endsWith(".dns") || property.endsWith(".dns1") ||
+ property.endsWith(".dns2") || property.endsWith(".dns3") ||
+ property.endsWith(".dns4")) {
+
+ // normalize the address
+
+ InetAddress ip = InetAddress.getByName(value);
+
+ if (ip == null) continue;
+
+ value = ip.getHostAddress();
+
+ if (value == null) continue;
+ if (value.length() == 0) continue;
+
+ server.add(value);
+ }
+ }
+ if (server.size() > 0) {
+ return server.toArray(new String[server.size()]);
+ }
+ } catch (IOException e) {
+ LOGGER.log(Level.WARNING, "Exception in findDNSByExec", e);
+ }
+ return null;
+ }
+
+ @Override
+ public boolean isAvailable() {
+ return PlatformDetection.isAndroid();
+ }
+
+}