Fix NPE in DNSResolver.lookupSRVRecords0

in case hostAddresses was null, the isEmpty() check before the log()
invocation would throw an NPE. Thanks to Ingo Bauersachs for reporting
this.

Fixes SMACK-788.
This commit is contained in:
Florian Schmaus 2017-12-01 09:28:21 +01:00
parent be4aacc71d
commit 47940ba5ad
4 changed files with 21 additions and 24 deletions

View File

@ -20,6 +20,7 @@ import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Arrays;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.jivesoftware.smack.ConnectionConfiguration.DnssecMode;
@ -91,6 +92,22 @@ public abstract class DNSResolver {
return Arrays.asList(inetAddressArray);
}
protected final boolean shouldContinue(CharSequence name, CharSequence hostname, List<InetAddress> hostAddresses) {
if (hostAddresses == null) {
return true;
}
// If hostAddresses is not null but empty, then the DNS resolution was successful but the domain did not
// have any A or AAAA resource records.
if (hostAddresses.isEmpty()) {
LOGGER.log(Level.INFO, "The DNS name " + name + ", points to a hostname (" + hostname
+ ") which has neither A or AAAA resource records. This is an indication of a broken DNS setup.");
return true;
}
return false;
}
private final void checkIfDnssecRequestedAndSupported(DnssecMode dnssecMode) {
if (dnssecMode != DnssecMode.disabled && !supportsDnssec) {
throw new UnsupportedOperationException("This resolver does not support DNSSEC");

View File

@ -1,6 +1,6 @@
/**
*
* Copyright 2013-2016 Florian Schmaus
* Copyright 2013-2017 Florian Schmaus
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@ -19,7 +19,6 @@ package org.jivesoftware.smack.util.dns.dnsjava;
import java.net.InetAddress;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import org.jivesoftware.smack.ConnectionConfiguration.DnssecMode;
import org.jivesoftware.smack.initializer.SmackInitializer;
@ -74,13 +73,7 @@ public class DNSJavaResolver extends DNSResolver implements SmackInitializer {
int weight = srvRecord.getWeight();
List<InetAddress> hostAddresses = lookupHostAddress0(host, failedAddresses, dnssecMode);
if (hostAddresses == null || hostAddresses.isEmpty()) {
// If hostAddresses is not null but empty, then the DNS resolution was successful but the domain did not
// have any A or AAAA resource records.
if (hostAddresses.isEmpty()) {
LOGGER.log(Level.INFO, "The DNS name " + name + ", points to a hostname (" + host
+ ") which has neither A or AAAA resource records. This is an indication of a broken DNS setup.");
}
if (shouldContinue(name, host, hostAddresses)) {
continue;
}

View File

@ -111,13 +111,7 @@ public class JavaxResolver extends DNSResolver implements SmackInitializer {
String host = srvRecordEntries[srvRecordEntries.length - 1];
List<InetAddress> hostAddresses = lookupHostAddress0(host, failedAddresses, dnssecMode);
if (hostAddresses == null || hostAddresses.isEmpty()) {
// If hostAddresses is not null but empty, then the DNS resolution was successful but the domain did not
// have any A or AAAA resource records.
if (hostAddresses.isEmpty()) {
LOGGER.log(Level.INFO, "The DNS name " + name + ", points to a hostname (" + host
+ ") which has neither A or AAAA resource records. This is an indication of a broken DNS setup.");
}
if (shouldContinue(name, host, hostAddresses)) {
continue;
}

View File

@ -24,7 +24,6 @@ import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.Set;
import java.util.logging.Level;
import org.jivesoftware.smack.ConnectionConfiguration.DnssecMode;
import org.jivesoftware.smack.initializer.SmackInitializer;
@ -91,13 +90,7 @@ public class MiniDnsResolver extends DNSResolver implements SmackInitializer {
for (SRV srv : result.getAnswers()) {
String hostname = srv.name.ace;
List<InetAddress> hostAddresses = lookupHostAddress0(hostname, failedAddresses, dnssecMode);
if (hostAddresses == null || hostAddresses.isEmpty()) {
// If hostAddresses is not null but empty, then the DNS resolution was successful but the domain did not
// have any A or AAAA resource records.
if (hostAddresses.isEmpty()) {
LOGGER.log(Level.INFO, "The DNS name " + name + ", points to a hostname (" + hostname
+ ") which has neither A or AAAA resource records. This is an indication of a broken DNS setup.");
}
if (shouldContinue(name, hostname, hostAddresses)) {
continue;
}