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Diffstat (limited to 'libs/minidns/src/main/java/de/measite/minidns/Client.java')
-rw-r--r--libs/minidns/src/main/java/de/measite/minidns/Client.java323
1 files changed, 0 insertions, 323 deletions
diff --git a/libs/minidns/src/main/java/de/measite/minidns/Client.java b/libs/minidns/src/main/java/de/measite/minidns/Client.java
deleted file mode 100644
index 827aa772..00000000
--- a/libs/minidns/src/main/java/de/measite/minidns/Client.java
+++ /dev/null
@@ -1,323 +0,0 @@
-package de.measite.minidns;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
-import java.io.LineNumberReader;
-import java.lang.reflect.Method;
-import java.net.DatagramPacket;
-import java.net.DatagramSocket;
-import java.net.InetAddress;
-import java.security.NoSuchAlgorithmException;
-import java.security.SecureRandom;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.HashSet;
-import java.util.Random;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-
-import de.measite.minidns.Record.CLASS;
-import de.measite.minidns.Record.TYPE;
-
-/**
- * A minimal DNS client for SRV/A/AAAA/NS and CNAME lookups, with IDN support.
- * This circumvents the missing javax.naming package on android.
- */
-public class Client {
-
- private static final Logger LOGGER = Logger.getLogger(Client.class.getName());
-
- /**
- * The internal random class for sequence generation.
- */
- protected Random random;
-
- /**
- * The buffer size for dns replies.
- */
- protected int bufferSize = 1500;
-
- /**
- * DNS timeout.
- */
- protected int timeout = 5000;
-
- /**
- * The internal DNS cache.
- */
- protected DNSCache cache;
-
- /**
- * Create a new DNS client with the given DNS cache.
- * @param cache The backend DNS cache.
- */
- public Client(DNSCache cache) {
- try {
- random = SecureRandom.getInstance("SHA1PRNG");
- } catch (NoSuchAlgorithmException e1) {
- random = new SecureRandom();
- }
- this.cache = cache;
- }
-
- /**
- * Create a new DNS client.
- */
- public Client() {
- this(null);
- }
-
- /**
- * Query a nameserver for a single entry.
- * @param name The DNS name to request.
- * @param type The DNS type to request (SRV, A, AAAA, ...).
- * @param clazz The class of the request (usually IN for Internet).
- * @param host The DNS server host.
- * @param port The DNS server port.
- * @return The response (or null on timeout / failure).
- * @throws IOException On IO Errors.
- */
- public DNSMessage query(String name, TYPE type, CLASS clazz, String host, int port)
- throws IOException
- {
- Question q = new Question(name, type, clazz);
- return query(q, host, port);
- }
-
- /**
- * Query a nameserver for a single entry.
- * @param name The DNS name to request.
- * @param type The DNS type to request (SRV, A, AAAA, ...).
- * @param clazz The class of the request (usually IN for Internet).
- * @param host The DNS server host.
- * @return The response (or null on timeout / failure).
- * @throws IOException On IO Errors.
- */
- public DNSMessage query(String name, TYPE type, CLASS clazz, String host)
- throws IOException
- {
- Question q = new Question(name, type, clazz);
- return query(q, host);
- }
-
- /**
- * Query the system nameserver for a single entry.
- * @param name The DNS name to request.
- * @param type The DNS type to request (SRV, A, AAAA, ...).
- * @param clazz The class of the request (usually IN for Internet).
- * @return The response (or null on timeout/error).
- * @return The DNSMessage reply or null.
- */
- public DNSMessage query(String name, TYPE type, CLASS clazz)
- {
- Question q = new Question(name, type, clazz);
- return query(q);
- }
-
- /**
- * Query a specific server for one entry.
- * @param q The question section of the DNS query.
- * @param host The dns server host.
- * @return The response (or null on timeout/error).
- * @throws IOException On IOErrors.
- */
- public DNSMessage query(Question q, String host) throws IOException {
- return query(q, host, 53);
- }
-
- /**
- * Query a specific server for one entry.
- * @param q The question section of the DNS query.
- * @param host The dns server host.
- * @param port the dns port.
- * @return The response (or null on timeout/error).
- * @throws IOException On IOErrors.
- */
- public DNSMessage query(Question q, String host, int port) throws IOException {
- DNSMessage dnsMessage = (cache == null) ? null : cache.get(q);
- if (dnsMessage != null) {
- return dnsMessage;
- }
- DNSMessage message = new DNSMessage();
- message.setQuestions(new Question[]{q});
- message.setRecursionDesired(true);
- message.setId(random.nextInt());
- byte[] buf = message.toArray();
- try (DatagramSocket socket = new DatagramSocket()) {
- DatagramPacket packet = new DatagramPacket(buf, buf.length,
- InetAddress.getByName(host), port);
- socket.setSoTimeout(timeout);
- socket.send(packet);
- packet = new DatagramPacket(new byte[bufferSize], bufferSize);
- socket.receive(packet);
- dnsMessage = DNSMessage.parse(packet.getData());
- if (dnsMessage.getId() != message.getId()) {
- return null;
- }
- for (Record record : dnsMessage.getAnswers()) {
- if (record.isAnswer(q)) {
- if (cache != null) {
- cache.put(q, dnsMessage);
- }
- break;
- }
- }
- return dnsMessage;
- }
- }
-
- /**
- * Query the system DNS server for one entry.
- * @param q The question section of the DNS query.
- * @return The response (or null on timeout/error).
- */
- public DNSMessage query(Question q) {
- // While this query method does in fact re-use query(Question, String)
- // we still do a cache lookup here in order to avoid unnecessary
- // findDNS()calls, which are expensive on Android. Note that we do not
- // put the results back into the Cache, as this is already done by
- // query(Question, String).
- DNSMessage message = cache.get(q);
- if (message != null) {
- return message;
- }
- String dnsServer[] = findDNS();
- for (String dns : dnsServer) {
- try {
- message = query(q, dns);
- if (message == null) {
- continue;
- }
- if (message.getResponseCode() !=
- DNSMessage.RESPONSE_CODE.NO_ERROR) {
- continue;
- }
- for (Record record: message.getAnswers()) {
- if (record.isAnswer(q)) {
- return message;
- }
- }
- } catch (IOException ioe) {
- LOGGER.log(Level.FINE, "IOException in query", ioe);
- }
- }
- return null;
- }
-
- /**
- * Retrieve a list of currently configured DNS servers.
- * @return The server array.
- */
- public String[] findDNS() {
- String[] result = findDNSByReflection();
- if (result != null) {
- LOGGER.fine("Got DNS servers via reflection: " + Arrays.toString(result));
- return result;
- }
-
- result = findDNSByExec();
- if (result != null) {
- LOGGER.fine("Got DNS servers via exec: " + Arrays.toString(result));
- return result;
- }
-
- // fallback for ipv4 and ipv6 connectivity
- // see https://developers.google.com/speed/public-dns/docs/using
- LOGGER.fine("No DNS found? Using fallback [8.8.8.8, [2001:4860:4860::8888]]");
-
- return new String[]{"8.8.8.8", "[2001:4860:4860::8888]"};
- }
-
- /**
- * Try to retrieve the list of dns server by executing getprop.
- * @return Array of servers, or null on failure.
- */
- protected String[] findDNSByExec() {
- try {
- Process process = Runtime.getRuntime().exec("getprop");
- InputStream inputStream = process.getInputStream();
- LineNumberReader lnr = new LineNumberReader(
- new InputStreamReader(inputStream));
- String line = null;
- HashSet<String> server = new HashSet<String>(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 (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;
- }
-
- /**
- * Try to retrieve the list of dns server by calling SystemProperties.
- * @return Array of servers, or null on failure.
- */
- protected String[] findDNSByReflection() {
- try {
- Class<?> SystemProperties =
- Class.forName("android.os.SystemProperties");
- Method method = SystemProperties.getMethod("get",
- new Class[] { String.class });
-
- ArrayList<String> servers = new ArrayList<String>(5);
-
- for (String propKey : new String[] {
- "net.dns1", "net.dns2", "net.dns3", "net.dns4"}) {
-
- String value = (String)method.invoke(null, propKey);
-
- if (value == null) continue;
- if (value.length() == 0) continue;
- if (servers.contains(value)) continue;
-
- InetAddress ip = InetAddress.getByName(value);
-
- if (ip == null) continue;
-
- value = ip.getHostAddress();
-
- if (value == null) continue;
- if (value.length() == 0) continue;
- if (servers.contains(value)) continue;
-
- servers.add(value);
- }
-
- if (servers.size() > 0) {
- return servers.toArray(new String[servers.size()]);
- }
- } catch (Exception e) {
- // we might trigger some problems this way
- LOGGER.log(Level.WARNING, "Exception in findDNSByReflection", e);
- }
- return null;
- }
-
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-10 09:26:15 +0000