001/** 002 * 003 * Copyright 2013-2018 Florian Schmaus 004 * 005 * Licensed under the Apache License, Version 2.0 (the "License"); 006 * you may not use this file except in compliance with the License. 007 * You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.jivesoftware.smack.util.dns.dnsjava; 018 019import java.net.InetAddress; 020import java.util.ArrayList; 021import java.util.List; 022 023import org.jivesoftware.smack.ConnectionConfiguration.DnssecMode; 024import org.jivesoftware.smack.initializer.SmackInitializer; 025import org.jivesoftware.smack.util.DNSUtil; 026import org.jivesoftware.smack.util.dns.DNSResolver; 027import org.jivesoftware.smack.util.dns.HostAddress; 028import org.jivesoftware.smack.util.dns.SRVRecord; 029 030import org.minidns.dnsname.DnsName; 031import org.xbill.DNS.Lookup; 032import org.xbill.DNS.Record; 033import org.xbill.DNS.TextParseException; 034import org.xbill.DNS.Type; 035 036/** 037 * This implementation uses the <a href="http://www.dnsjava.org/">dnsjava</a> implementation for resolving DNS addresses. 038 * 039 */ 040public class DNSJavaResolver extends DNSResolver implements SmackInitializer { 041 042 private static final DNSJavaResolver instance = new DNSJavaResolver(); 043 044 public static DNSResolver getInstance() { 045 return instance; 046 } 047 048 public DNSJavaResolver() { 049 super(false); 050 } 051 052 @Override 053 protected List<SRVRecord> lookupSRVRecords0(DnsName name, List<HostAddress> failedAddresses, DnssecMode dnssecMode) { 054 List<SRVRecord> res = new ArrayList<>(); 055 056 Lookup lookup; 057 try { 058 lookup = new Lookup(name.ace, Type.SRV); 059 } 060 catch (TextParseException e) { 061 throw new IllegalStateException(e); 062 } 063 064 Record[] recs = lookup.run(); 065 if (recs == null) 066 return res; 067 068 for (Record record : recs) { 069 org.xbill.DNS.SRVRecord srvRecord = (org.xbill.DNS.SRVRecord) record; 070 if (srvRecord != null && srvRecord.getTarget() != null) { 071 DnsName host = DnsName.from(srvRecord.getTarget().toString()); 072 int port = srvRecord.getPort(); 073 int priority = srvRecord.getPriority(); 074 int weight = srvRecord.getWeight(); 075 076 List<InetAddress> hostAddresses = lookupHostAddress0(host, failedAddresses, dnssecMode); 077 if (shouldContinue(name, host, hostAddresses)) { 078 continue; 079 } 080 081 SRVRecord r = new SRVRecord(host, port, priority, weight, hostAddresses); 082 res.add(r); 083 } 084 } 085 086 return res; 087 } 088 089 public static void setup() { 090 DNSUtil.setDNSResolver(getInstance()); 091 } 092 093 @Override 094 public List<Exception> initialize() { 095 setup(); 096 return null; 097 } 098 099}