fix resolving IP if SRV violences RFC2782

2 files changed, 65 insertions, 21 deletions

diff --git a/src/main/java/de/pixart/messenger/utils/Resolver.java b/src/main/java/de/pixart/messenger/utils/Resolver.java
index a7c286cc7..aa05043e7 100644
--- a/src/main/java/de/pixart/messenger/utils/Resolver.java
+++ b/src/main/java/de/pixart/messenger/utils/Resolver.java
@@ -128,10 +128,14 @@ public class Resolver {
             }
         });
         threads[2] = new Thread(() -> {
-            List<Result> list = resolveNoSrvRecords(DNSName.from(domain), DEFAULT_PORT_XMPP, true);
+            try {
+                final List<Result> list = resolveNoSrvRecords(DNSName.from(domain), DEFAULT_PORT_XMPP, true);
                 synchronized (fallbackResults) {
                     fallbackResults.addAll(list);
                 }
+            } catch (Throwable throwable) {
+                Log.d(Config.LOGTAG, Resolver.class.getSimpleName() + ": resolving no SRV record (STARTTLS)", throwable);
+            }
         });
         for (Thread thread : threads) {
             thread.start();
@@ -187,7 +191,7 @@ public class Resolver {
         final List<Thread> fallbackThreads = new ArrayList<>();
 
         for (SRV record : result.getAnswersOrEmptySet()) {
-            if (record.name.length() == 0) {
+            if (record.name.length() == 0 && record.priority == 0) {
                 continue;
             }
             threads.add(new Thread(() -> {
@@ -198,6 +202,11 @@ public class Resolver {
             }));
             threads.add(new Thread(() -> {
                 final List<Result> ipv4s = resolveIp(record, A.class, result.isAuthenticData(), directTls);
+                if (ipv4s.size() == 0) {
+                    Result resolverResult = Result.fromRecord(record, directTls);
+                    resolverResult.authenticated = result.isAuthenticData();
+                    ipv4s.add(resolverResult);
+                }
                 synchronized (results) {
                     results.addAll(ipv4s);
                 }
@@ -211,11 +220,11 @@ public class Resolver {
                             fallbackResults.addAll(ipv6s);
                         }
                         final List<Result> ipv4s = resolveIp(record, cname.name, A.class, cnames.isAuthenticData(), directTls);
-                        synchronized (results) {
+                        synchronized (fallbackResults) {
                             fallbackResults.addAll(ipv4s);
                         }
                     }
-                    Log.d(Config.LOGTAG, Resolver.class.getSimpleName() + "cname in srv (agains RFC2782) - run slow fallback");
+                    Log.d(Config.LOGTAG, Resolver.class.getSimpleName() + " cname in srv (against RFC2782) - run slow fallback");
                 } catch (Throwable throwable) {
                     Log.i(Config.LOGTAG, Resolver.class.getSimpleName() + " error resolving srv cname-fallback records", throwable);
                 }
@@ -285,6 +294,7 @@ public class Resolver {
         } catch (Throwable throwable) {
             Log.d(Config.LOGTAG, Resolver.class.getSimpleName() + "error resolving fallback records", throwable);
         }
+        results.add(Result.createDefault(dnsName, port));
         return results;
     }
 
@@ -315,7 +325,7 @@ public class Resolver {
         if (r.size() == 0) return null;
 
         Result result;
-        if (r.size() == 1) {
+        if (r.size() == 1 && r.get(0).ip != null) {
             result = r.get(0);
             result.setLogID(logID);
             result.connect();
@@ -387,11 +397,27 @@ public class Resolver {
             result.timeRequested = System.currentTimeMillis();
             result.port = srv.port;
             result.hostname = srv.name;
+            try {
+                result.ip = InetAddress.getByName(result.hostname.toString());
+            } catch (UnknownHostException e) {
+                result.ip = null;
+                e.printStackTrace();
+            }
             result.directTls = directTls;
             result.priority = srv.priority;
             return result;
         }
 
+        static Result createDefault(final DNSName hostname, final int port) {
+            InetAddress ip = null;
+            try {
+                ip = InetAddress.getByName(hostname.toString());
+            } catch (UnknownHostException e) {
+                e.printStackTrace();
+            }
+            return createDefault(hostname, ip, port);
+        }
+
         static Result createDefault(final DNSName hostname, final InetAddress ip, final int port) {
             Result result = new Result();
             result.timeRequested = System.currentTimeMillis();
@@ -464,6 +490,10 @@ public class Resolver {
             if (this.socket != null) {
                 this.disconnect();
             }
+            if (this.ip == null || this.port == 0) {
+                Log.d(Config.LOGTAG, "Resolver did not get IP:port (" + this.ip + ":" + this.port + ")");
+                return;
+            }
             final InetSocketAddress addr = new InetSocketAddress(this.ip, this.port);
             this.socket = new Socket();
             try {
diff --git a/src/main/java/de/pixart/messenger/xmpp/XmppConnection.java b/src/main/java/de/pixart/messenger/xmpp/XmppConnection.java
index a41924e08..05b5bc73e 100644
--- a/src/main/java/de/pixart/messenger/xmpp/XmppConnection.java
+++ b/src/main/java/de/pixart/messenger/xmpp/XmppConnection.java
@@ -18,7 +18,6 @@ import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.ConnectException;
-import java.net.IDN;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.MalformedURLException;
@@ -317,20 +316,35 @@ public class XmppConnection implements Runnable {
                 }
             } else {
                 final String domain = account.getJid().getDomain();
-                final Resolver.Result storedBackupResult = mXmppConnectionService.databaseBackend.findResolverResult(domain);
-                Resolver.Result result = null;
+                Resolver.Result results;
                 final boolean hardcoded = extended && !account.getHostname().isEmpty();
                 if (hardcoded) {
-                    result = Resolver.fromHardCoded(account.getHostname(), account.getPort());
-                } else if (storedBackupResult != null && !storedBackupResult.isOutdated()) {
-                    storedBackupResult.connect();
-                    result = storedBackupResult;
+                    results = Resolver.fromHardCoded(account.getHostname(), account.getPort());
+                } else {
+                    results = Resolver.resolve(domain);
+                }
+                if (Thread.currentThread().isInterrupted()) {
+                    Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": Thread was interrupted");
+                    return;
+                }
+                if (results == null) {
+                    Log.e(Config.LOGTAG,account.getJid().asBareJid()+": Resolver results were empty");
+                    return;
+                }
+                final Resolver.Result storedBackupResult;
+                if (hardcoded) {
+                    storedBackupResult = null;
+                } else {
+                    storedBackupResult = mXmppConnectionService.databaseBackend.findResolverResult(domain);
+                    if (storedBackupResult != null && results != storedBackupResult && !storedBackupResult.isOutdated()) {
+                        results = storedBackupResult;
                         Log.d(Config.LOGTAG, account.getJid().asBareJid() + ": loaded backup resolver result from db: " + storedBackupResult);
                     }
-                if (result == null || result.getSocket() == null) {
-                    result = Resolver.resolve(domain);
                 }
-                if (result == null) {
+                if (results == null || results.getSocket() == null) {
+                    results = Resolver.resolve(domain);
+                }
+                if (results == null) {
                     throw new UnknownHostException();
                 }
                 if (Thread.currentThread().isInterrupted()) {
@@ -339,13 +353,13 @@ public class XmppConnection implements Runnable {
                 }
                 try {
                     // if tls is true, encryption is implied and must not be started
-                    features.encryptionEnabled = result.isDirectTls();
-                    verifiedHostname = result.isAuthenticated() ? result.getHostname().toString() : null;
+                    features.encryptionEnabled = results.isDirectTls();
+                    verifiedHostname = results.isAuthenticated() ? results.getHostname().toString() : null;
                     Log.d(Config.LOGTAG,"verified hostname " + verifiedHostname);
                     Log.d(Config.LOGTAG, account.getJid().asBareJid().toString()
-                            + ": using values from resolver " + result.toString());
+                            + ": using values from resolver " + results.toString());
 
-                    localSocket = result.getSocket();
+                    localSocket = results.getSocket();
 
                     if (features.encryptionEnabled) {
                         localSocket = upgradeSocketToTls(localSocket);
@@ -354,8 +368,8 @@ public class XmppConnection implements Runnable {
                     localSocket.setSoTimeout(Config.SOCKET_TIMEOUT * 1000);
                     if (startXmpp(localSocket)) {
                         localSocket.setSoTimeout(0); //reset to 0; once the connection is established we don’t want this
-                        if (!hardcoded && !result.equals(storedBackupResult)) {
-                            mXmppConnectionService.databaseBackend.saveResolverResult(domain, result);
+                        if (!hardcoded && !results.equals(storedBackupResult)) {
+                            mXmppConnectionService.databaseBackend.saveResolverResult(domain, results);
                         }
                         // successfully connected to server that speaks xmpp
                     } else {