From 1a57599da2b99f37d8d5ca611a4c4f83f7fd2e00 Mon Sep 17 00:00:00 2001
From: Daniel Gultsch <daniel@gultsch.de>
Date: Tue, 8 Nov 2016 10:14:34 +0100
Subject: [PATCH] lower case incoming dns records

---
 .../siacs/conversations/utils/DNSHelper.java  | 41 +++++++++++--------
 1 file changed, 23 insertions(+), 18 deletions(-)

diff --git a/src/main/java/eu/siacs/conversations/utils/DNSHelper.java b/src/main/java/eu/siacs/conversations/utils/DNSHelper.java
index ac64cf2e..a8aba6db 100644
--- a/src/main/java/eu/siacs/conversations/utils/DNSHelper.java
+++ b/src/main/java/eu/siacs/conversations/utils/DNSHelper.java
@@ -19,6 +19,7 @@ import java.net.UnknownHostException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 import java.util.Random;
 import java.util.TreeMap;
 import java.util.Map;
@@ -148,26 +149,29 @@ public class DNSHelper {
 		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())) {
+				final String name = rr.getName() != null ? rr.getName().toLowerCase(Locale.US) : null;
+				if (d instanceof SRV && NameUtil.idnEquals(qname, name)) {
 					SRV srv = (SRV) d;
 					if (!priorities.containsKey(srv.getPriority())) {
 						priorities.put(srv.getPriority(),new ArrayList<TlsSrv>());
 					}
 					priorities.get(srv.getPriority()).add(new TlsSrv(srv, tls));
+				} else if (d instanceof SRV) {
+					Log.d(Config.LOGTAG,"found unrecognized SRV record with name: "+name);
 				}
 				if (d instanceof A) {
 					A a = (A) d;
-					if (!ips4.containsKey(rr.getName())) {
-						ips4.put(rr.getName(), new ArrayList<String>());
+					if (!ips4.containsKey(name)) {
+						ips4.put(name, new ArrayList<String>());
 					}
-					ips4.get(rr.getName()).add(a.toString());
+					ips4.get(name).add(a.toString());
 				}
 				if (d instanceof AAAA) {
 					AAAA aaaa = (AAAA) d;
-					if (!ips6.containsKey(rr.getName())) {
-						ips6.put(rr.getName(), new ArrayList<String>());
+					if (!ips6.containsKey(name)) {
+						ips6.put(name, new ArrayList<String>());
 					}
-					ips6.get(rr.getName()).add("[" + aaaa.toString() + "]");
+					ips6.get(name).add("[" + aaaa.toString() + "]");
 				}
 			}
 		}
@@ -177,8 +181,8 @@ public class DNSHelper {
 		Bundle bundle = new Bundle();
 		try {
 			client.setTimeout(Config.SOCKET_TIMEOUT * 1000);
-			final String qname = "_xmpp-client._tcp." + host;
-			final String tlsQname = "_xmpps-client._tcp." + host;
+			final String qname = "_xmpp-client._tcp." + host.toLowerCase(Locale.US);
+			final String tlsQname = "_xmpps-client._tcp." + host.toLowerCase(Locale.US);
 			Log.d(Config.LOGTAG, "using dns server: " + dnsServer.getHostAddress() + " to look up " + host);
 
 			final Map<Integer, List<TlsSrv>> priorities = new TreeMap<>();
@@ -218,27 +222,28 @@ public class DNSHelper {
 			}
 			for (final TlsSrv tlsSrv : result) {
 				final SRV srv = tlsSrv.srv;
-				if (ips6.containsKey(srv.getName())) {
-					values.add(createNamePortBundle(srv.getName(),srv.getPort(),ips6, tlsSrv.tls));
+				final String name = srv.getName() != null ? srv.getName().toLowerCase(Locale.US) : null;
+				if (ips6.containsKey(name)) {
+					values.add(createNamePortBundle(name,srv.getPort(),ips6, tlsSrv.tls));
 				} else {
 					try {
-						DNSMessage response = client.query(srv.getName(), TYPE.AAAA, CLASS.IN, dnsServer.getHostAddress());
+						DNSMessage response = client.query(name, 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(), tlsSrv.tls));
+							values.add(createNamePortBundle(name, srv.getPort(), response.getAnswers()[i].getPayload(), tlsSrv.tls));
 						}
 					} catch (SocketTimeoutException e) {
 						Log.d(Config.LOGTAG,"ignoring timeout exception when querying AAAA record on "+dnsServer.getHostAddress());
 					}
 				}
-				if (ips4.containsKey(srv.getName())) {
-					values.add(createNamePortBundle(srv.getName(),srv.getPort(),ips4, tlsSrv.tls));
+				if (ips4.containsKey(name)) {
+					values.add(createNamePortBundle(name,srv.getPort(),ips4, tlsSrv.tls));
 				} else {
-					DNSMessage response = client.query(srv.getName(), TYPE.A, CLASS.IN, dnsServer.getHostAddress());
+					DNSMessage response = client.query(name, 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(), tlsSrv.tls));
+						values.add(createNamePortBundle(name,srv.getPort(),response.getAnswers()[i].getPayload(), tlsSrv.tls));
 					}
 				}
-				values.add(createNamePortBundle(srv.getName(), srv.getPort(), tlsSrv.tls));
+				values.add(createNamePortBundle(name, srv.getPort(), tlsSrv.tls));
 			}
 			bundle.putParcelableArrayList("values", values);
 		} catch (SocketTimeoutException e) {